Design Study for A Low-Cost LH2 Turbopump

NASA Technical Reports Server (NTRS)

Japikse, David; Baines, Nicholas; Platt, Michael J.

2000-01-01

A preliminary design study, focusing on potential component selections and design for manufacturing and assembly (DFMAR1) analysis, is presented in this study. The investigation focused on a nominal cost liquid hydrogen turbopump suitable for a private launch class vehicle. Utilizing a "turbocharger-like" design philosophy, preliminary feasibility studies of the basic pump design class, the rotordynamic design class, and the turbine design class were conducted with associated DFMA evaluations. Reasonable cost levels and sensible levels of product assurance have been established.

Using extreme phenotype sampling to identify the rare causal variants of quantitative traits in association studies.

PubMed

Li, Dalin; Lewinger, Juan Pablo; Gauderman, William J; Murcray, Cassandra Elizabeth; Conti, David

2011-12-01

Variants identified in recent genome-wide association studies based on the common-disease common-variant hypothesis are far from fully explaining the hereditability of complex traits. Rare variants may, in part, explain some of the missing hereditability. Here, we explored the advantage of the extreme phenotype sampling in rare-variant analysis and refined this design framework for future large-scale association studies on quantitative traits. We first proposed a power calculation approach for a likelihood-based analysis method. We then used this approach to demonstrate the potential advantages of extreme phenotype sampling for rare variants. Next, we discussed how this design can influence future sequencing-based association studies from a cost-efficiency (with the phenotyping cost included) perspective. Moreover, we discussed the potential of a two-stage design with the extreme sample as the first stage and the remaining nonextreme subjects as the second stage. We demonstrated that this two-stage design is a cost-efficient alternative to the one-stage cross-sectional design or traditional two-stage design. We then discussed the analysis strategies for this extreme two-stage design and proposed a corresponding design optimization procedure. To address many practical concerns, for example measurement error or phenotypic heterogeneity at the very extremes, we examined an approach in which individuals with very extreme phenotypes are discarded. We demonstrated that even with a substantial proportion of these extreme individuals discarded, an extreme-based sampling can still be more efficient. Finally, we expanded the current analysis and design framework to accommodate the CMC approach where multiple rare-variants in the same gene region are analyzed jointly. © 2011 Wiley Periodicals, Inc.

Using Extreme Phenotype Sampling to Identify the Rare Causal Variants of Quantitative Traits in Association Studies

PubMed Central

Li, Dalin; Lewinger, Juan Pablo; Gauderman, William J.; Murcray, Cassandra Elizabeth; Conti, David

2014-01-01

Variants identified in recent genome-wide association studies based on the common-disease common-variant hypothesis are far from fully explaining the hereditability of complex traits. Rare variants may, in part, explain some of the missing hereditability. Here, we explored the advantage of the extreme phenotype sampling in rare-variant analysis and refined this design framework for future large-scale association studies on quantitative traits. We first proposed a power calculation approach for a likelihood-based analysis method. We then used this approach to demonstrate the potential advantages of extreme phenotype sampling for rare variants. Next, we discussed how this design can influence future sequencing-based association studies from a cost-efficiency (with the phenotyping cost included) perspective. Moreover, we discussed the potential of a two-stage design with the extreme sample as the first stage and the remaining nonextreme subjects as the second stage. We demonstrated that this two-stage design is a cost-efficient alternative to the one-stage cross-sectional design or traditional two-stage design. We then discussed the analysis strategies for this extreme two-stage design and proposed a corresponding design optimization procedure. To address many practical concerns, for example measurement error or phenotypic heterogeneity at the very extremes, we examined an approach in which individuals with very extreme phenotypes are discarded. We demonstrated that even with a substantial proportion of these extreme individuals discarded, an extreme-based sampling can still be more efficient. Finally, we expanded the current analysis and design framework to accommodate the CMC approach where multiple rare-variants in the same gene region are analyzed jointly. PMID:21922541

Study designs may influence results: the problems with questionnaire-based case-control studies on the epidemiology of glioma.

PubMed

Johansen, Christoffer; Schüz, Joachim; Andreasen, Anne-Marie Serena; Dalton, Susanne Oksbjerg

2017-03-28

Glioma is a rare brain tumour with a very poor prognosis and the search for modifiable factors is intense. We reviewed the literature concerning risk factors for glioma obtained in case-control designed epidemiological studies in order to discuss the influence of this methodology on the observed results. When reviewing the association between three exposures, medical radiation, exogenous hormone use and allergy, we critically appraised the evidence from both case-control and cohort studies. For medical radiation and hormone replacement therapy (HRT), questionnaire-based case-control studies appeared to show an inverse association, whereas nested case-control and cohort studies showed no association. For allergies, the inverse association was observed irrespective of study design. We recommend that the questionnaire-based case-control design be placed lower in the hierarchy of studies for establishing cause-and-effect for diseases such as glioma. We suggest that a state-of-the-art case-control study should, as a minimum, be accompanied by extensive validation of the exposure assessment methods and the representativeness of the study sample with regard to the exposures of interest. Otherwise, such studies cannot be regarded as 'hypothesis testing' but only 'hypothesis generating'. We consider that this holds true for all questionnaire-based case-control studies on cancer and other chronic diseases, although perhaps not to the same extent for each exposure-outcome combination.

Early subsidence of shape-closed hip arthroplasty stems is associated with late revision. A systematic review and meta-analysis of 24 RSA studies and 56 survival studies.

PubMed

van der Voort, Paul; Pijls, Bart G; Nieuwenhuijse, Marc J; Jasper, Jorrit; Fiocco, Marta; Plevier, Josepha W M; Middeldorp, Saskia; Valstar, Edward R; Nelissen, Rob G H H

2015-01-01

Few studies have addressed the association between early migration of femoral stems and late aseptic revision in total hip arthroplasty. We performed a meta-regression analysis on 2 parallel systematic reviews and meta-analyses to determine the association between early migration and late aseptic revision of femoral stems. Of the 2 reviews, one covered early migration data obtained from radiostereometric analysis (RSA) studies and the other covered long-term aseptic revision rates obtained from survival studies with endpoint revision for aseptic loosening. Stems were stratified according to the design concept: cemented shape-closed, cemented force-closed, and uncemented. A weighted regression model was used to assess the association between early migration and late aseptic revision, and to correct for confounders. Thresholds for acceptable and unacceptable migration were determined in accordance with the national joint registries (≤ 5% revision at 10 years) and the NICE criteria (≤ 10% revision at 10 years). 24 studies (731 stems) were included in the RSA review and 56 studies (20,599 stems) were included in the survival analysis review. Combining both reviews for the 3 design concepts showed that for every 0.1-mm increase in 2-year subsidence, as measured with RSA, there was a 4% increase in revision rate for the shape-closed stem designs. This association remained after correction for age, sex, diagnosis, hospital type, continent, and study quality. The threshold for acceptable migration of shape-closed designs was defined at 0.15 mm; stems subsiding less than 0.15 mm in 2 years had revision rates of less than 5% at 10 years, while stems exceeding 0.15 mm subsidence had revision rates of more than 5%. There was a clinically relevant association between early subsidence of shape-closed femoral stems and late revision for aseptic loosening. This association can be used to assess the safety of shape-closed stem designs. The published research is not sufficient to allow us to make any conclusions regarding such an association for the force-closed and uncemented stems.

An exploration into study design for biomarker identification: issues and recommendations.

PubMed

Hall, Jacqueline A; Brown, Robert; Paul, Jim

2007-01-01

Genomic profiling produces large amounts of data and a challenge remains in identifying relevant biological processes associated with clinical outcome. Many candidate biomarkers have been identified but few have been successfully validated and make an impact clinically. This review focuses on some of the study design issues encountered in data mining for biomarker identification with illustrations of how study design may influence the final results. This includes issues of clinical endpoint use and selection, power, statistical, biological and clinical significance. We give particular attention to study design for the application of supervised clustering methods for identification of gene networks associated with clinical outcome and provide recommendations for future work to increase the success of identification of clinically relevant biomarkers.

Waste Handeling Building Conceptual Study

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

G.W. Rowe

2000-11-06

The objective of the ''Waste Handling Building Conceptual Study'' is to develop proposed design requirements for the repository Waste Handling System in sufficient detail to allow the surface facility design to proceed to the License Application effort if the proposed requirements are approved by DOE. Proposed requirements were developed to further refine waste handling facility performance characteristics and design constraints with an emphasis on supporting modular construction, minimizing fuel inventory, and optimizing facility maintainability and dry handling operations. To meet this objective, this study attempts to provide an alternative design to the Site Recommendation design that is flexible, simple, reliable,more » and can be constructed in phases. The design concept will be input to the ''Modular Design/Construction and Operation Options Report'', which will address the overall program objectives and direction, including options and issues associated with transportation, the subsurface facility, and Total System Life Cycle Cost. This study (herein) is limited to the Waste Handling System and associated fuel staging system.« less

Influence of Study Design on Outcomes Following Reflexology Massage: An Integrative and Critical Review of Interventional Studies.

PubMed

McVicar, Andrew; Greenwood, Christina; Ellis, Carol; LeForis, Chantelle

2016-09-01

Interpretation of the efficacy of reflexology is hindered by inconsistent research designs and complicated by professional views that criteria of randomized controlled trials (RCTs)are not ideal to research holistic complementary and alternative medicine practice. The influence of research designs on study outcomes is not known. This integrative review sought to evaluate this possibility. Thirty-seven interventional studies (2000-2014) were identified; they had RCT or non-RCT design and compared reflexology outcomes against a control/comparison group. Viability of integrating RCT and non-RCT studies into a single database was first evaluated by appraisal of 16 reporting fields related to study setting and objectives, sample demographics, methodologic design, and treatment fidelity and assessment against Jadad score quality criteria for RCTs. For appraisal, the database was stratified into RCT/non-RCT or Jadad score of 3 or more or less than 3. Deficits in reporting were identified for blind assignment of participants, dropout/completion rate, and School of Reflexology. For comparison purposes, these fields were excluded from subsequent analysis for evidence of association between design fields and of fields with study outcomes. Thirty-one studies applied psychometric tools and 20 applied biometric tools (14 applied both). A total of 116 measures were used. Type of measure was associated with study objectives (p < 0.001; chi-square), in particular of psychometric measures with a collated "behavioral/cognitive" objective. Significant outcomes were more likely (p < 0.001; chi-square) for psychometric than for biometric measures. Neither type of outcome was associated with choice of RCT or non-RCT method, but psychometric responses were associated (p = 0.007) with a nonmassage control strategy. The review supports psychometric responses to reflexology when study design uses a nonmassage control strategy. Findings suggest that an evaluation of outcomes against sham reflexology massage and other forms of massage, as well as a narrower focus of study objective, may clarify whether there is a relationship between study design and efficacy of reflexology.

Association between Soy Isoflavone Intake and Breast Cancer Risk for Pre- and Post-Menopausal Women: A Meta-Analysis of Epidemiological Studies

PubMed Central

Zheng, Yi; Wei, Shiqing; Li, Ye; Guo, Tong; Yin, Ping

2014-01-01

Background Conclusions drawn from meta-analyses on the association between soy isoflavone intake and breast cancer risk for pre- and post-menopausal women are not fully consistent. These meta-analyses did not explore the influence of different study designs on the pooled results on the basis of distinguishing between pre- and post-menopausal women. Methodology and Principal Findings We performed a meta-analysis of 35 studies which reported results of association between soy isoflavone intake and breast cancer risk for pre- and/or post-menopausal women, calculated pooled odds ratios and their 95% confidence intervals of pre- and post-menopausal women respectively, and further explored soy isoflavone-breast cancer association on the basis of considering different study regions and designs. Summary results suggested that soy isoflavone intake has a protective effect against breast cancer for both pre- and post-menopausal women. However, they are influenced by study design and region. Pooled ORs of studies carried out in Asian countries suggested that soy isoflavone’s protective effect exist in both pre- and post-menopausal women (OR = 0.59, 95%CI: 0.48–0.69 for premenopausal women; OR = 0.59, 95%CI: 0.44–0.74 for postmenopausal women). However, there are some differences between the results pooled from different study designs for women in Asian countries (test for consistency, P = 0.04). Pooled OR of studies on postmenopausal women in Western countries suggested that soy isoflavone intake has a marginally significant protective effect (OR = 0.92; 95%CI: 0.83∼1.00), but further analyses stratifying by study design found no statistically significant association. Conclusions We meta-analyzed more and newer research results, and separated women according to menopausal status to explore soy isoflavone-breast cancer association. We founded that soy isoflavone intake could lower the risk of breast cancer for both pre- and post-menopausal women in Asian countries. However, for women in Western countries, pre- or post-menopausal, there is no evidence to suggest an association between intake of soy isoflavone and breast cancer. PMID:24586662

How Associate Deans' Positions Are Designed within the Context of the Top 50 Colleges and Schools of Education.

ERIC Educational Resources Information Center

Jackson, Jerlando F. L.; Gmelch, Walter H.

This study examined the design of associate deans' positions within the context of the top 50 colleges and schools of education, focusing on three design parameters (job specialization, formalization of behavior in carrying out the job, and training and indoctrination required for the job). Researchers examined data derived from a compilation of…

Associations between personal exposures and ambient concentrations of nitrogen dioxide: A quantitative research synthesis

NASA Astrophysics Data System (ADS)

Meng, Q. Y.; Svendsgaard, D.; Kotchmar, D. J.; Pinto, J. P.

2012-09-01

Although positive associations between ambient NO2 concentrations and personal exposures have generally been found by exposure studies, the strength of the associations varied among studies. Differences in results could be related to differences in study design and in exposure factors. However, the effects of study design, exposure factors, and sampling and measurement errors on the strength of the personal-ambient associations have not been evaluated quantitatively in a systematic manner. A quantitative research synthesis was conducted to examine these issues based on peer-reviewed publications in the past 30 years. Factors affecting the strength of the personal-ambient associations across the studies were also examined with meta-regression. Ambient NO2 was found to be significantly associated with personal NO2 exposures, with estimates of 0.42, 0.16, and 0.72 for overall pooled, longitudinal and daily average correlation coefficients based on random-effects meta-analysis. This conclusion was robust after correction for publication bias with correlation coefficients of 0.37, 0.16 and 0.45. We found that season and some population characteristics, such as pre-existing disease, were significant factors affecting the strength of the personal-ambient associations. More meaningful and rigorous comparisons would be possible if greater detail were published on the study design (e.g. local and indoor sources, housing characteristics, etc.) and data quality (e.g., detection limits and percent of data above detection limits).

Collective Design of an E-Textbook: Teachers' Collective Documentation

ERIC Educational Resources Information Center

Gueudet, Ghislaine; Pepin, Birgit; Sabra, Hussein; Trouche, Luc

2016-01-01

In this study, we investigated design processes in teacher collectives, which have been made possible by new "digital" opportunities: platforms, discussion lists, etc. The object of our study is the French Sésamath teacher association and its design of a grade 10 e-textbook, more precisely the design of the "functions" chapter.…

Assessing the Design and Development of Hybrid Linked Learning Professional Development Programs for Teachers: Challenges and Successes

ERIC Educational Resources Information Center

Erener, Eren

2017-01-01

This study informs instructional designers, all stakeholders in higher education and K-12, of the successes and challenges associated with designing and developing online/hybrid Linked Learning courses. The study examines via surveys and interviews the perspectives of instructional designers, subject matter experts, students, and course…

Extending Animal Models to Explore Social Rewards Associated with Designated Smoking Areas on College Campuses

ERIC Educational Resources Information Center

Lochbihler, Stephanie L.; Miller, Daniel A.; Etcheverry, Paul E.

2014-01-01

Objective: Animal studies have shown that when nicotine is administered in the presence of other animals (as compared with alone), it is more rewarding. As a human analogue to these studies, rewards associated with designated smoking areas on university campuses were examined, since these areas promote using nicotine in the presence of others.…

Associate Degree Curriculum for Engineering Technology.

ERIC Educational Resources Information Center

Campbell, Clifton P.

Presented is a two-year associate degree curriculum for Engineering Technology. Specializations are provided in civil, electronics, and mechanical technology. The civil engineering technology specialization facilitates three major areas of study, and mechanical technology includes design and production options. Each curriculum was designed to…

Analysis of midpalatal miniscrew-assisted maxillary molar distalization patterns with simultaneous use of fixed appliances: A preliminary study

PubMed Central

Mah, Su-Jung; Kim, Ji-Eun; Ahn, Eun Jin; Nam, Jong-Hyun; Kim, Ji-Young

2016-01-01

Skeletal anchorage-assisted upper molar distalization has become one of the standard treatment modalities for the correction of Class II malocclusion. The purpose of this study was to analyze maxillary molar movement patterns according to appliance design, with the simultaneous use of buccal fixed orthodontic appliances. The authors devised two distinct types of midpalatal miniscrew-assisted maxillary molar distalizers, a lingual arch type and a pendulum type. Fourteen patients treated with one of the two types of distalizers were enrolled in the study, and the patterns of tooth movement associated with each type were compared. Pre- and post-treatment lateral cephalograms were analyzed. The lingual arch type was associated with relatively bodily upper molar distalization, while the pendulum type was associated with distal tipping with intrusion of the upper molar. Clinicians should be aware of the expected tooth movement associated with each appliance design. Further well designed studies with larger sample sizes are required. PMID:26877983

Supporting Active Living Through Community Plans: The Association of Planning Documents With Design Standards and Features.

PubMed

Peterson, Erin L; Carlson, Susan A; Schmid, Thomas L; Brown, David R; Galuska, Deborah A

2018-01-01

The purpose of this study was to examine the association between the presence of supportive community planning documents in US municipalities with design standards and requirements supportive of active living. Cross-sectional study using data from the 2014 National Survey of Community-Based Policy and Environmental Supports for Healthy Eating and Active Living. Nationally representative sample of US municipalities. Respondents are 2005 local officials. Assessed: (1) The presence of design standards and feature requirements and (2) the association between planning documents and design standards and feature requirements supportive of active living in policies for development. Using logistic regression, significant trends were identified in the presence of design standards and feature requirements by plan and number of supportive objectives present. Prevalence of design standards ranged from 19% (developer dedicated right-of-way for bicycle infrastructure development) to 50% (traffic-calming features in areas with high pedestrian and bicycle volume). Features required in policies for development ranged from 14% (short/medium pedestrian-scale block sizes) to 44% (minimum sidewalk widths of 5 feet) of municipalities. As the number of objectives in municipal plans increased, there was a significant and positive trend ( P < .05) in the prevalence of each design standard and requirement. Municipal planning documents containing objectives supportive of physical activity are associated with design standards and feature requirements supportive of activity-friendly communities.

Impact of Contact Lens Material, Design, and Fitting on Discomfort.

PubMed

Stapleton, Fiona; Tan, Jacqueline

2017-01-01

To review the effect of contact lens (CL) material, design, and fitting characteristics on CL discomfort. A PubMed search identified publications describing subjective comfort and CL material, fitting, and design parameters. The review included clinical signs associated with discomfort that may be a consequence of these parameters. Reduced lens movement or more CL tightness were associated with improved comfort. Increased lens-induced paralimbal conjunctival staining and indentation, considered as quasi-indicators of CL fitting or edge design, were also associated with better comfort. No recent studies have evaluated varying CL design parameters and subjective comfort. Silicone hydrogel CLs are no different in comfort compared with hydrogel CLs. Lower equilibrium water content is associated with improved comfort in hydrogel CL wear. Coefficient of friction shows promise as a material factor potentially associated with comfort. Lid wiper epitheliopathy and lid-parallel conjunctival folds have been linked with comfort in established wearers. Recent studies have confirmed the association between more mobile CLs and more discomfort, whereas closer conformity of the CL to the bulbar conjunctiva improved subjective comfort. There is no evidence to support the perceived comfort difference between silicone hydrogel and hydrogel CL. There has been limited progress in understanding the impact of varying specific CL design parameters. Although specific clinical signs may be predictive of discomfort, their role in the natural history of discomfort remains unclear. A better understanding of the relationship between coefficient of friction and comfort and strategies to improve lubricity may hold promise for limiting CL discomfort.

Are quantitative trait-dependent sampling designs cost-effective for analysis of rare and common variants?

PubMed

Yilmaz, Yildiz E; Bull, Shelley B

2011-11-29

Use of trait-dependent sampling designs in whole-genome association studies of sequence data can reduce total sequencing costs with modest losses of statistical efficiency. In a quantitative trait (QT) analysis of data from the Genetic Analysis Workshop 17 mini-exome for unrelated individuals in the Asian subpopulation, we investigate alternative designs that sequence only 50% of the entire cohort. In addition to a simple random sampling design, we consider extreme-phenotype designs that are of increasing interest in genetic association analysis of QTs, especially in studies concerned with the detection of rare genetic variants. We also evaluate a novel sampling design in which all individuals have a nonzero probability of being selected into the sample but in which individuals with extreme phenotypes have a proportionately larger probability. We take differential sampling of individuals with informative trait values into account by inverse probability weighting using standard survey methods which thus generalizes to the source population. In replicate 1 data, we applied the designs in association analysis of Q1 with both rare and common variants in the FLT1 gene, based on knowledge of the generating model. Using all 200 replicate data sets, we similarly analyzed Q1 and Q4 (which is known to be free of association with FLT1) to evaluate relative efficiency, type I error, and power. Simulation study results suggest that the QT-dependent selection designs generally yield greater than 50% relative efficiency compared to using the entire cohort, implying cost-effectiveness of 50% sample selection and worthwhile reduction of sequencing costs.

Design and implementation of observational studies to measure disease burden with a focus on stroke.

PubMed

Howard, George; Howard, Virginia J

2018-02-01

Observational epidemiological studies have the dual goals of measuring disease burden and assessing the association between exposures and outcomes. This report focuses on the first of these goals and provides an overview of design considerations of commonly used approaches, specifically community surveillance studies, cross-sectional studies, and longitudinal cohort studies. Each of these designs has strengths and weaknesses, with no study design being superior in all cases. Rather, these designs are complementary to achieve a better understanding of the burden of stroke.

Age 60 Study. Part 1. Bibliographic Database

DTIC Science & Technology

1994-10-01

seven of these aircraft types participated in a spectacle design study. Experimental spectacles were designed for each pilot and evaluated for...observation flight administered by observers who were uninformed of the details of the experimental design . Students and instructors also completed a critique...intraindividual lability in field-dependence-field independence, and (4) various measurement, sampling, and experimental design concerns associated

LWS design replacement study: Optimum design and tradeoff analysis

NASA Technical Reports Server (NTRS)

1973-01-01

A design for two long-wavelength (LW) focal-plane and cooler assemblies, including associated preamplifiers and post-amplifiers is presented. The focal-planes and associated electronic assemblies are intended as direct replacement hardware to be installed into the existing 24-channel multispectral scanner used with the NASA Earth Observations Aircraft Program. An organization skilled in the art of LWIR systems can fabricate and deliver the two long-wavelength focal-plane assemblies described in this report when provided with the data and drawings developed during the performance of this contract. The concepts developed during the study including the alternative approaches and selection of components are discussed. Modifications to the preliminary design as reported in a preliminary design review meeting have also been included.

Signal design study for shuttle/TDRSS Ku-band uplink

NASA Technical Reports Server (NTRS)

1976-01-01

The adequacy of the signal design approach chosen for the TDRSS/orbiter uplink was evaluated. Critical functions and/or components associated with the baseline design were identified, and design alternatives were developed for those areas considered high risk. A detailed set of RF and signal processing performance specifications for the orbiter hardware associated with the TDRSS/orbiter Ku band uplink was analyzed. Performances of a detailed design of the PN despreader, the PSK carrier synchronization loop, and the symbol synchronizer are identified. The performance of the downlink signal by means of computer simulation to obtain a realistic determination of bit error rate degradations was studied. The three channel PM downlink signal was detailed by means of analysis and computer simulation.

Smoking in Australian University Students and Its Association with Socio-Demographic Factors, Stress, Health Status, Coping Strategies, and Attitude

ERIC Educational Resources Information Center

Sun, Jing; Buys, Nicholas; Stewart, Donald; Shum, David; Farquhar, Lynette

2011-01-01

Purpose: This study aims to evaluate the prevalence of smoking amongst university students in Brisbane, Australia and associated risk factors. Design/methodology/approach: A cross-sectional design was used for the study. A sample of 2,414 university students aged 18-30 was examined to estimate the prevalence of tobacco use. Smoking was measured by…

Neighborhood Design, Physical Activity, and Wellbeing: Applying the Walkability Model.

PubMed

Zuniga-Teran, Adriana A; Orr, Barron J; Gimblett, Randy H; Chalfoun, Nader V; Guertin, David P; Marsh, Stuart E

2017-01-13

Neighborhood design affects lifestyle physical activity, and ultimately human wellbeing. There are, however, a limited number of studies that examine neighborhood design types. In this research, we examine four types of neighborhood designs: traditional development, suburban development, enclosed community, and cluster housing development, and assess their level of walkability and their effects on physical activity and wellbeing. We examine significant associations through a questionnaire ( n = 486) distributed in Tucson, Arizona using the Walkability Model. Among the tested neighborhood design types, traditional development showed significant associations and the highest value for walkability, as well as for each of the two types of walking (recreation and transportation) representing physical activity. Suburban development showed significant associations and the highest mean values for mental health and wellbeing. Cluster housing showed significant associations and the highest mean value for social interactions with neighbors and for perceived safety from crime. Enclosed community did not obtain the highest means for any wellbeing benefit. The Walkability Model proved useful in identifying the walkability categories associated with physical activity and perceived crime. For example, the experience category was strongly and inversely associated with perceived crime. This study provides empirical evidence of the importance of including vegetation, particularly trees, throughout neighborhoods in order to increase physical activity and wellbeing. Likewise, the results suggest that regular maintenance is an important strategy to improve mental health and overall wellbeing in cities.

Neighborhood Design, Physical Activity, and Wellbeing: Applying the Walkability Model

PubMed Central

Zuniga-Teran, Adriana A.; Orr, Barron J.; Gimblett, Randy H.; Chalfoun, Nader V.; Guertin, David P.; Marsh, Stuart E.

2017-01-01

Neighborhood design affects lifestyle physical activity, and ultimately human wellbeing. There are, however, a limited number of studies that examine neighborhood design types. In this research, we examine four types of neighborhood designs: traditional development, suburban development, enclosed community, and cluster housing development, and assess their level of walkability and their effects on physical activity and wellbeing. We examine significant associations through a questionnaire (n = 486) distributed in Tucson, Arizona using the Walkability Model. Among the tested neighborhood design types, traditional development showed significant associations and the highest value for walkability, as well as for each of the two types of walking (recreation and transportation) representing physical activity. Suburban development showed significant associations and the highest mean values for mental health and wellbeing. Cluster housing showed significant associations and the highest mean value for social interactions with neighbors and for perceived safety from crime. Enclosed community did not obtain the highest means for any wellbeing benefit. The Walkability Model proved useful in identifying the walkability categories associated with physical activity and perceived crime. For example, the experience category was strongly and inversely associated with perceived crime. This study provides empirical evidence of the importance of including vegetation, particularly trees, throughout neighborhoods in order to increase physical activity and wellbeing. Likewise, the results suggest that regular maintenance is an important strategy to improve mental health and overall wellbeing in cities. PMID:28098785

Intent inferencing by an intelligent operator's associate - A validation study

NASA Technical Reports Server (NTRS)

Jones, Patricia M.

1988-01-01

In the supervisory control of a complex, dynamic system, one potential form of aiding for the human operator is a computer-based operator's associate. The design philosophy of the operator's associate is that of 'amplifying' rather than automating human skills. In particular, the associate possesses understanding and control properties. Understanding allows it to infer operator intentions and thus form the basis for context-dependent advice and reminders; control properties allow the human operator to dynamically delegate individual tasks or subfunctions to the associate. This paper focuses on the design, implementation, and validation of the intent inferencing function. Two validation studies are described which empirically demonstrate the viability of the proposed approach to intent inferencing.

Genome-wide association study using extreme truncate selection identifies novel genes affecting bone mineral density and fracture risk.

PubMed

Duncan, Emma L; Danoy, Patrick; Kemp, John P; Leo, Paul J; McCloskey, Eugene; Nicholson, Geoffrey C; Eastell, Richard; Prince, Richard L; Eisman, John A; Jones, Graeme; Sambrook, Philip N; Reid, Ian R; Dennison, Elaine M; Wark, John; Richards, J Brent; Uitterlinden, Andre G; Spector, Tim D; Esapa, Chris; Cox, Roger D; Brown, Steve D M; Thakker, Rajesh V; Addison, Kathryn A; Bradbury, Linda A; Center, Jacqueline R; Cooper, Cyrus; Cremin, Catherine; Estrada, Karol; Felsenberg, Dieter; Glüer, Claus-C; Hadler, Johanna; Henry, Margaret J; Hofman, Albert; Kotowicz, Mark A; Makovey, Joanna; Nguyen, Sing C; Nguyen, Tuan V; Pasco, Julie A; Pryce, Karena; Reid, David M; Rivadeneira, Fernando; Roux, Christian; Stefansson, Kari; Styrkarsdottir, Unnur; Thorleifsson, Gudmar; Tichawangana, Rumbidzai; Evans, David M; Brown, Matthew A

2011-04-01

Osteoporotic fracture is a major cause of morbidity and mortality worldwide. Low bone mineral density (BMD) is a major predisposing factor to fracture and is known to be highly heritable. Site-, gender-, and age-specific genetic effects on BMD are thought to be significant, but have largely not been considered in the design of genome-wide association studies (GWAS) of BMD to date. We report here a GWAS using a novel study design focusing on women of a specific age (postmenopausal women, age 55-85 years), with either extreme high or low hip BMD (age- and gender-adjusted BMD z-scores of +1.5 to +4.0, n = 1055, or -4.0 to -1.5, n = 900), with replication in cohorts of women drawn from the general population (n = 20,898). The study replicates 21 of 26 known BMD-associated genes. Additionally, we report suggestive association of a further six new genetic associations in or around the genes CLCN7, GALNT3, IBSP, LTBP3, RSPO3, and SOX4, with replication in two independent datasets. A novel mouse model with a loss-of-function mutation in GALNT3 is also reported, which has high bone mass, supporting the involvement of this gene in BMD determination. In addition to identifying further genes associated with BMD, this study confirms the efficiency of extreme-truncate selection designs for quantitative trait association studies.

Genome-Wide Association Study Using Extreme Truncate Selection Identifies Novel Genes Affecting Bone Mineral Density and Fracture Risk

PubMed Central

Duncan, Emma L.; Danoy, Patrick; Kemp, John P.; Leo, Paul J.; McCloskey, Eugene; Nicholson, Geoffrey C.; Eastell, Richard; Prince, Richard L.; Eisman, John A.; Jones, Graeme; Sambrook, Philip N.; Reid, Ian R.; Dennison, Elaine M.; Wark, John; Richards, J. Brent; Uitterlinden, Andre G.; Spector, Tim D.; Esapa, Chris; Cox, Roger D.; Brown, Steve D. M.; Thakker, Rajesh V.; Addison, Kathryn A.; Bradbury, Linda A.; Center, Jacqueline R.; Cooper, Cyrus; Cremin, Catherine; Estrada, Karol; Felsenberg, Dieter; Glüer, Claus-C.; Hadler, Johanna; Henry, Margaret J.; Hofman, Albert; Kotowicz, Mark A.; Makovey, Joanna; Nguyen, Sing C.; Nguyen, Tuan V.; Pasco, Julie A.; Pryce, Karena; Reid, David M.; Rivadeneira, Fernando; Roux, Christian; Stefansson, Kari; Styrkarsdottir, Unnur; Thorleifsson, Gudmar; Tichawangana, Rumbidzai; Evans, David M.; Brown, Matthew A.

2011-01-01

Osteoporotic fracture is a major cause of morbidity and mortality worldwide. Low bone mineral density (BMD) is a major predisposing factor to fracture and is known to be highly heritable. Site-, gender-, and age-specific genetic effects on BMD are thought to be significant, but have largely not been considered in the design of genome-wide association studies (GWAS) of BMD to date. We report here a GWAS using a novel study design focusing on women of a specific age (postmenopausal women, age 55–85 years), with either extreme high or low hip BMD (age- and gender-adjusted BMD z-scores of +1.5 to +4.0, n = 1055, or −4.0 to −1.5, n = 900), with replication in cohorts of women drawn from the general population (n = 20,898). The study replicates 21 of 26 known BMD–associated genes. Additionally, we report suggestive association of a further six new genetic associations in or around the genes CLCN7, GALNT3, IBSP, LTBP3, RSPO3, and SOX4, with replication in two independent datasets. A novel mouse model with a loss-of-function mutation in GALNT3 is also reported, which has high bone mass, supporting the involvement of this gene in BMD determination. In addition to identifying further genes associated with BMD, this study confirms the efficiency of extreme-truncate selection designs for quantitative trait association studies. PMID:21533022

Tubal risk markers for failure to place transcervical sterilization coils

PubMed Central

Leyser-Whalen, Ophra; Rouhani, Mahta; Rahman, Mahbubur; Berenson, Abbey B

2011-01-01

Background There is a growing body of literature on placement rates of the Essure® procedure, yet prior studies have not attempted to identify tubal-associated risk factors for placement failures. The current study examines risk markers associated with the inability to deploy the Essure® coils into the tubal lumen using the new ESS305 design. Study Design We used electronic medical record data to assess risk markers associated with the inability to place the Essure coils in the tubal lumen using the new ESS305 design. A total of 310 attempted procedures between June 14, 2007, and April 29, 2011 were analyzed. Results There were 18 tubal failures (5.8%) out of the 310 attempted procedures. A history of a prior sexually transmitted infection (STI) was associated with tubal failure (OR 2.64, 95% confidence interval (CI) 1.01–6.90; p=.048). Conclusions We speculate that the observed association between a prior STI and an inability to place the coil was due to a past history of pelvic inflammatory disease. PMID:22036044

Improving power and robustness for detecting genetic association with extreme-value sampling design.

PubMed

Chen, Hua Yun; Li, Mingyao

2011-12-01

Extreme-value sampling design that samples subjects with extremely large or small quantitative trait values is commonly used in genetic association studies. Samples in such designs are often treated as "cases" and "controls" and analyzed using logistic regression. Such a case-control analysis ignores the potential dose-response relationship between the quantitative trait and the underlying trait locus and thus may lead to loss of power in detecting genetic association. An alternative approach to analyzing such data is to model the dose-response relationship by a linear regression model. However, parameter estimation from this model can be biased, which may lead to inflated type I errors. We propose a robust and efficient approach that takes into consideration of both the biased sampling design and the potential dose-response relationship. Extensive simulations demonstrate that the proposed method is more powerful than the traditional logistic regression analysis and is more robust than the linear regression analysis. We applied our method to the analysis of a candidate gene association study on high-density lipoprotein cholesterol (HDL-C) which includes study subjects with extremely high or low HDL-C levels. Using our method, we identified several SNPs showing a stronger evidence of association with HDL-C than the traditional case-control logistic regression analysis. Our results suggest that it is important to appropriately model the quantitative traits and to adjust for the biased sampling when dose-response relationship exists in extreme-value sampling designs. © 2011 Wiley Periodicals, Inc.

Meta-Analysis of the INSIG2 Association with Obesity Including 74,345 Individuals: Does Heterogeneity of Estimates Relate to Study Design?

PubMed Central

Loos, Ruth J. F.; Kronenberg, Florian; Adamkova, Vera; Anand, Sonia S.; Ardlie, Kristin; Biebermann, Heike; Bjerregaard, Peter; Boeing, Heiner; Bouchard, Claude; Ciullo, Marina; Cooper, Jackie A.; Corella, Dolores; Dina, Christian; Engert, James C.; Fisher, Eva; Francès, Francesc; Froguel, Philippe; Hebebrand, Johannes; Hegele, Robert A.; Hinney, Anke; Hoehe, Margret R.; Hu, Frank B.; Hubacek, Jaroslav A.; Humphries, Steve E.; Hunt, Steven C.; Illig, Thomas; Järvelin, Marjo-Riita; Kaakinen, Marika; Kollerits, Barbara; Krude, Heiko; Kumar, Jitender; Lange, Leslie A.; Langer, Birgit; Li, Shengxu; Luchner, Andreas; Lyon, Helen N.; Meyre, David; Mohlke, Karen L.; Mooser, Vincent; Nebel, Almut; Nguyen, Thuy Trang; Paulweber, Bernhard; Perusse, Louis; Qi, Lu; Rankinen, Tuomo; Rosskopf, Dieter; Schreiber, Stefan; Sengupta, Shantanu; Sorice, Rossella; Suk, Anita; Thorleifsson, Gudmar; Thorsteinsdottir, Unnur; Völzke, Henry; Vimaleswaran, Karani S.; Wareham, Nicholas J.; Waterworth, Dawn; Yusuf, Salim; Lindgren, Cecilia; McCarthy, Mark I.; Lange, Christoph; Hirschhorn, Joel N.

2009-01-01

The INSIG2 rs7566605 polymorphism was identified for obesity (BMI≥30 kg/m2) in one of the first genome-wide association studies, but replications were inconsistent. We collected statistics from 34 studies (n = 74,345), including general population (GP) studies, population-based studies with subjects selected for conditions related to a better health status (‘healthy population’, HP), and obesity studies (OB). We tested five hypotheses to explore potential sources of heterogeneity. The meta-analysis of 27 studies on Caucasian adults (n = 66,213) combining the different study designs did not support overall association of the CC-genotype with obesity, yielding an odds ratio (OR) of 1.05 (p-value = 0.27). The I2 measure of 41% (p-value = 0.015) indicated between-study heterogeneity. Restricting to GP studies resulted in a declined I2 measure of 11% (p-value = 0.33) and an OR of 1.10 (p-value = 0.015). Regarding the five hypotheses, our data showed (a) some difference between GP and HP studies (p-value = 0.012) and (b) an association in extreme comparisons (BMI≥32.5, 35.0, 37.5, 40.0 kg/m2 versus BMI<25 kg/m2) yielding ORs of 1.16, 1.18, 1.22, or 1.27 (p-values 0.001 to 0.003), which was also underscored by significantly increased CC-genotype frequencies across BMI categories (10.4% to 12.5%, p-value for trend = 0.0002). We did not find evidence for differential ORs (c) among studies with higher than average obesity prevalence compared to lower, (d) among studies with BMI assessment after the year 2000 compared to those before, or (e) among studies from older populations compared to younger. Analysis of non-Caucasian adults (n = 4889) or children (n = 3243) yielded ORs of 1.01 (p-value = 0.94) or 1.15 (p-value = 0.22), respectively. There was no evidence for overall association of the rs7566605 polymorphism with obesity. Our data suggested an association with extreme degrees of obesity, and consequently heterogeneous effects from different study designs may mask an underlying association when unaccounted for. The importance of study design might be under-recognized in gene discovery and association replication so far. PMID:19851442

Does Education Lower Allostatic Load? A Co-twin Control Study

PubMed Central

Hamdi, Nayla R.; South, Susan C.; Krueger, Robert F.

2016-01-01

Many studies have found that education is associated with better health, but the causal basis of this association is unclear. The current study used a co-twin control design to examine if differences in years of education within twin pairs predict allostatic load. The strength of this design is that it controls for genetic and other familial confounds shared between twins. The sample consisted of 381 twins (with 292 twins from 146 complete pairs; mean age=57; 61% female) who participated in the biomarker project of the Midlife Development in the United States (MIDUS) study. Individual-level analyses showed a significant, negative association between years of education and allostatic load, but this association was explained entirely by familial influences shared between twins. The results of this study suggest that schooling does not itself protect against allostatic load. PMID:26778778

Genetic polymorphisms for estimating risk of atrial fibrillation: a literature-based meta-analysis

PubMed Central

Smith, J. Gustav; Almgren, Peter; Engström, Gunnar; Hedblad, Bo; Platonov, Pyotr G.; Newton-Cheh, Christopher; Melander, Olle

2013-01-01

Objectives Genome-wide association studies have recently identified genetic polymorphisms associated with common, etiologically complex diseases, for which direct-to-consumer genetic testing with provision of absolute genetic risk estimates is marketed by commercial companies. Polymorphisms associated with atrial fibrillation (AF) have shown relatively large risk estimates but the robustness of such estimates across populations and study designs has not been studied. Design A systematic literature review with meta-analysis and assessment of between-study heterogeneity was performed for single nucleotide polymorphisms (SNPs) in the six genetic regions associated with AF in genome-wide or candidate gene studies. Results Data from 18 samples of European ancestry (n=12,100 cases; 115,702 controls) were identified for the SNP on chromosome 4q25 (rs220733), 16 samples (n=12,694 cases; 132,602 controls) for the SNP on 16q22 (rs2106261) and 4 samples (n=5,272 cases; 59,725 controls) for the SNP in KCNH2 (rs1805123). Only the discovery studies were identified for SNPs on 1q21 and in GJA5 and IL6R, why no meta-analyses were performed for those SNPs. In overall random-effects meta-analyses, association with AF was observed for both SNPs from genome-wide studies on 4q25 (OR 1.67, 95% CI=1.50–1.86, p=2×10−21) and 16q22 (OR 1.21, 95% CI=1.13–1.29, p=1×10−8), but not the SNP in KCNH2 from candidate gene studies (p=0.15). There was substantial effect heterogeneity across case-control and cross-sectional studies for both polymorphisms (I2=0.50–0.78, p<0.05), but not across prospective cohort studies (I2=0.39, p=0.15). Both polymorphisms were robustly associated with AF for each study design individually (p<0.05). Conclusions In meta-analyses including up to 150,000 individuals, polymorphisms in two genetic regions were robustly associated with AF across all study designs but with substantial context-dependency of risk estimates. PMID:22690879

Methodological issues of genetic association studies.

PubMed

Simundic, Ana-Maria

2010-12-01

Genetic association studies explore the association between genetic polymorphisms and a certain trait, disease or predisposition to disease. It has long been acknowledged that many genetic association studies fail to replicate their initial positive findings. This raises concern about the methodological quality of these reports. Case-control genetic association studies often suffer from various methodological flaws in study design and data analysis, and are often reported poorly. Flawed methodology and poor reporting leads to distorted results and incorrect conclusions. Many journals have adopted guidelines for reporting genetic association studies. In this review, some major methodological determinants of genetic association studies will be discussed.

Development of a turbomachinery design optimization procedure using a multiple-parameter nonlinear perturbation method

NASA Technical Reports Server (NTRS)

Stahara, S. S.

1984-01-01

An investigation was carried out to complete the preliminary development of a combined perturbation/optimization procedure and associated computational code for designing optimized blade-to-blade profiles of turbomachinery blades. The overall purpose of the procedures developed is to provide demonstration of a rapid nonlinear perturbation method for minimizing the computational requirements associated with parametric design studies of turbomachinery flows. The method combines the multiple parameter nonlinear perturbation method, successfully developed in previous phases of this study, with the NASA TSONIC blade-to-blade turbomachinery flow solver, and the COPES-CONMIN optimization procedure into a user's code for designing optimized blade-to-blade surface profiles of turbomachinery blades. Results of several design applications and a documented version of the code together with a user's manual are provided.

Study designs to enhance identification of genetic factors in healthy aging.

PubMed

Manolio, Teri A

2007-12-01

The sequencing of the human genome and the growing understanding of its function are providing powerful new research tools for identifying genetic variants that are associated with complex diseases and traits. Somewhat less emphasis has been given to genes related to healthy aging, although the approaches for studying health-related traits are analogous to those used for disease-related studies. A critical step prior to the design of such studies is to define a healthy aging phenotype, which should be standardized to permit comparisons across studies and should involve more than simple longevity. Phenotypes of particular value for genetic research are those with high heritability and close relationships to gene products or pathways, preferably with minimal or at least measurable environmental influences. Appropriate study designs to identify genotype-phenotype associations include family-based linkage studies, candidate gene association analyses, and genome-wide association studies. Advances in genotyping and sequencing technologies, and the generation of the human haplotype map database, now permit the cost-effective investigation of the very large sample sizes needed for genome-wide association studies in unrelated individuals. Challenges in interpretation and translation of such studies include assessing the potential for bias and confounding, as well as determining the clinical validity and utility of findings proposed for wider application. Many such studies are currently supported or being planned across the National Institutes of Health (NIH), and lend themselves to the kind of coordinated clinical research envisioned in programs such as the NIH Roadmap.

Factors Associated With Exercise Behavior in People With Parkinson Disease

PubMed Central

Cavanaugh, James T.; Earhart, Gammon M.; Ford, Matthew P.; Foreman, K. Bo; Fredman, Lisa; Boudreau, Jennifer K.; Dibble, Leland E.

2011-01-01

Background The benefits of exercise for reducing disability in people with Parkinson disease (PD) are becoming more evident. Optimal benefit, however, requires regular and sustained participation. Factors associated with engaging in regular exercise have received little scientific scrutiny in people with PD. Objective The purpose of this study was to explore factors associated with exercise behavior in patients with PD using the International Classification of Functioning, Disability and Health (ICF) as a guiding framework. Design This was a cross-sectional study. Methods The participants in this study were 260 patients with PD from 4 institutions. Participants were designated as “exercisers” or “nonexercisers” based on responses to the Stages of Readiness to Exercise Questionnaire. Exercise status was validated using the Physical Activity Scale for the Elderly and an activity monitor. Factors potentially associated with exercise behavior included measures of body structure and function, activity, participation, environmental factors, and personal factors. Their relative contributions were analyzed using logistic regression and quantified with odds ratios. Results One hundred sixty-four participants (63%) were designated as exercisers. Participants with high self-efficacy were more than twice as likely to engage in regular exercise than those with low self-efficacy (adjusted odds ratio=2.34, 95% confidence interval=1.30–4.23). College educated and older participants also were more likely to exercise. Disabling influences of impairments, activity limitations, and participation restrictions were not associated with exercise behavior. Limitations The cross-sectional nature of the study limited the ability to make causal inferences. Conclusions Self-efficacy, rather than disability, appears to be strongly associated with whether ambulatory, community-dwelling people with PD exercise regularly. The results of this study suggest that physical therapists should include strategies to increase exercise self-efficacy when designing patient intervention programs for patients with PD. PMID:22003171

Investigating Instructional Design Management and Leadership Competencies--A Delphi Study

ERIC Educational Resources Information Center

Gardner, Joel; Chongwony, Lewis; Washington, Tawana

2018-01-01

Research in instructional design and educational technology journals typically focuses on the theories, technologies, and processes related to practice of instructional design. There is little research emphasis, however, on leadership and management of instructional design in higher education. Investigating the competencies associated with…

Disease-Concordant Twins Empower Genetic Association Studies.

PubMed

Tan, Qihua; Li, Weilong; Vandin, Fabio

2017-01-01

Genome-wide association studies with moderate sample sizes are underpowered, especially when testing SNP alleles with low allele counts, a situation that may lead to high frequency of false-positive results and lack of replication in independent studies. Related individuals, such as twin pairs concordant for a disease, should confer increased power in genetic association analysis because of their genetic relatedness. We conducted a computer simulation study to explore the power advantage of the disease-concordant twin design, which uses singletons from disease-concordant twin pairs as cases and ordinary healthy samples as controls. We examined the power gain of the twin-based design for various scenarios (i.e., cases from monozygotic and dizygotic twin pairs concordant for a disease) and compared the power with the ordinary case-control design with cases collected from the unrelated patient population. Simulation was done by assigning various allele frequencies and allelic relative risks for different mode of genetic inheritance. In general, for achieving a power estimate of 80%, the sample sizes needed for dizygotic and monozygotic twin cases were one half and one fourth of the sample size of an ordinary case-control design, with variations depending on genetic mode. Importantly, the enriched power for dizygotic twins also applies to disease-concordant sibling pairs, which largely extends the application of the concordant twin design. Overall, our simulation revealed a high value of disease-concordant twins in genetic association studies and encourages the use of genetically related individuals for highly efficiently identifying both common and rare genetic variants underlying human complex diseases without increasing laboratory cost. © 2016 John Wiley & Sons Ltd/University College London.

City Governments and Aging in Place: Community Design, Transportation and Housing Innovation Adoption

ERIC Educational Resources Information Center

Lehning, Amanda J.

2012-01-01

Purpose of the study: To examine the characteristics associated with city government adoption of community design, housing, and transportation innovations that could benefit older adults. Design and methods: A mixed-methods study with quantitative data collected via online surveys from 62 city planners combined with qualitative data collected via…

Partial gravity habitat study: With application to lunar base design

NASA Technical Reports Server (NTRS)

Capps, Stephen; Lorandos, Jason; Akhidime, Eval; Bunch, Michael; Lund, Denise; Moore, Nathan; Murakawa, Kio; Bell, Larry; Trotti, Guillermo; Neubek, Deb

1989-01-01

Comprehensive design requirements associated with designing habitats for humans in a partial gravity environment were investigated and then applied to a lunar base design. Other potential sites for application include planetary surfaces such as Mars, variable gravity research facilities, or a rotating spacecraft. Design requirements for partial gravity environments include: (1) locomotion changes in less than normal Earth gravity; (2) facility design issues, such as interior configuration, module diameter and geometry; and (3) volumetric requirements based on the previous as well as psychological issues involved in prolonged isolation. For application to a Lunar Base, it was necessary to study the exterior architecture and configuration to insure optimum circulation patterns while providing dual egress. Radiation protection issues were addressed to provide a safe and healthy environment for the crew, and finally, the overall site was studied to locate all associated facilities in context with the habitat. Mission planning was not the purpose of this study; therefore, a Lockheed scenario was used as an outline for the Lunar Base application, which was then modified to meet the project needs.

Born to Lead? A Twin Design and Genetic Association Study of Leadership Role Occupancy*

PubMed Central

De Neve, Jan-Emmanuel; Mikhaylov, Slava; Dawes, Christopher T.; Christakis, Nicholas A.; Fowler, James H.

2013-01-01

We address leadership emergence and the possibility that there is a partially innate predisposition to occupy a leadership role. Employing twin design methods on data from the National Longitudinal Study of Adolescent Health, we estimate the heritability of leadership role occupancy at 24%. Twin studies do not point to specific genes or neurological processes that might be involved. We therefore also conduct association analysis on the available genetic markers. The results show that leadership role occupancy is associated with rs4950, a single nucleotide polymorphism (SNP) residing on a neuronal acetylcholine receptor gene (CHRNB3). We replicate this family-based genetic association result on an independent sample in the Framingham Heart Study. This is the first study to identify a specific genotype associated with the tendency to occupy a leadership position. The results suggest that what determines whether an individual occupies a leadership position is the complex product of genetic and environmental influences; with a particular role for rs4950. PMID:23459689

Consistency between cross-sectional and longitudinal SNP: blood lipid associations.

PubMed

Costanza, Michael C; Beer-Borst, Sigrid; James, Richard W; Gaspoz, Jean-Michel; Morabia, Alfredo

2012-02-01

Various studies have linked different genetic single nucleotide polymorphisms (SNPs) to different blood lipids (BL), but whether these "connections" were identified using cross-sectional or longitudinal (i.e., changes over time) designs has received little attention. Cross-sectional and longitudinal assessments of BL [total, high-, low-density lipoprotein cholesterol (TC, HDL, LDL), triglycerides (TG)] and non-genetic factors (body mass index, smoking, alcohol intake) were measured for 2,002 Geneva, Switzerland, adults during 1999-2008 (two measurements, median 6 years apart), and 20 SNPs in 13 BL metabolism-related genes. Fixed and mixed effects repeated measures linear regression models, respectively, were employed to identify cross-sectional and longitudinal SNP:BL associations among the 1,516 (76%) study participants who reported not being treated for hypercholesterolemia at either measurement time. One-third more (12 vs. 9) longitudinal than cross-sectional associations were found [Bonferroni-adjusted two-tailed p < 0.00125 (=0.05/2)/20) for each of the four ensembles of 20 SNP:individual BL associations tested under the two study designs]. There was moderate consistency between the cross-sectional and longitudinal findings, with eight SNP:BL associations consistently identified across both study designs: [APOE.2 and APOE.4 (rs7412 and rs429358)]:TC; HL/LIPC (rs2070895):HDL; [APOB (rs1367117), APOE.2 and APOE.4 (rs7412 and rs429358)]:LDL; [APOA5 (rs2072560) and APOC III (rs5128)]:TG. The results suggest that cross-sectional studies, which include most genome-wide association studies (GWAS), can assess the large majority of SNP:BL associations. In the present analysis, which was much less powered than a GWAS, the cross-sectional study was around 2/3 (67%) as efficient as the longitudinal study.

Towards non-conventional methods of designing register-based epidemiological studies: An application to pediatric research.

PubMed

Gong, Tong; Brew, Bronwyn; Sjölander, Arvid; Almqvist, Catarina

2017-07-01

Various epidemiological designs have been applied to investigate the causes and consequences of fetal growth restriction in register-based observational studies. This review seeks to provide an overview of several conventional designs, including cohort, case-control and more recently applied non-conventional designs such as family-based designs. We also discuss some practical points regarding the application and interpretation of family-based designs. Definitions of each design, the study population, the exposure and the outcome measures are briefly summarised. Examples of study designs are taken from the field of low birth-weight research for illustrative purposes. Also examined are relative advantages and disadvantages of each design in terms of assumptions, potential selection and information bias, confounding and generalisability. Kinship data linkage, statistical models and result interpretation are discussed specific to family-based designs. When all information is retrieved from registers, there is no evident preference of the case-control design over the cohort design to estimate odds ratios. All conventional designs included in the review are prone to bias, particularly due to residual confounding. Family-based designs are able to reduce such bias and strengthen causal inference. In the field of low birth-weight research, family-based designs have been able to confirm a negative association not confounded by genetic or shared environmental factors between low birth weight and the risk of asthma. We conclude that there is a broader need for family-based design in observational research as evidenced by the meaningful contributions to the understanding of the potential causal association between low birth weight and subsequent outcomes.

Searching for missing heritability: Designing rare variant association studies

PubMed Central

Zuk, Or; Schaffner, Stephen F.; Samocha, Kaitlin; Do, Ron; Hechter, Eliana; Kathiresan, Sekar; Daly, Mark J.; Neale, Benjamin M.; Sunyaev, Shamil R.; Lander, Eric S.

2014-01-01

Genetic studies have revealed thousands of loci predisposing to hundreds of human diseases and traits, revealing important biological pathways and defining novel therapeutic hypotheses. However, the genes discovered to date typically explain less than half of the apparent heritability. Because efforts have largely focused on common genetic variants, one hypothesis is that much of the missing heritability is due to rare genetic variants. Studies of common variants are typically referred to as genomewide association studies, whereas studies of rare variants are often simply called sequencing studies. Because they are actually closely related, we use the terms common variant association study (CVAS) and rare variant association study (RVAS). In this paper, we outline the similarities and differences between RVAS and CVAS and describe a conceptual framework for the design of RVAS. We apply the framework to address key questions about the sample sizes needed to detect association, the relative merits of testing disruptive alleles vs. missense alleles, frequency thresholds for filtering alleles, the value of predictors of the functional impact of missense alleles, the potential utility of isolated populations, the value of gene-set analysis, and the utility of de novo mutations. The optimal design depends critically on the selection coefficient against deleterious alleles and thus varies across genes. The analysis shows that common variant and rare variant studies require similarly large sample collections. In particular, a well-powered RVAS should involve discovery sets with at least 25,000 cases, together with a substantial replication set. PMID:24443550

(TUCSON) STUDY DESIGN AND PRELIMINARY EXPOSURE FINDINGS ASSOCIATED WITH THE DEARS

EPA Science Inventory

The Detroit Exposure and Aerosol Research Study (DEARS) is a three-year field monitoring study initiated in 2004 that is designed to measure exposure and describe exposure relationships for air toxics, PM components, PM from specific sources, and criteria pollutants. Detroit, Mic...

The perceived value of using BIM for energy simulation

NASA Astrophysics Data System (ADS)

Lewis, Anderson M.

Building Information Modeling (BIM) is becoming an increasingly important tool in the Architectural, Engineering & Construction (AEC) industries. Some of the benefits associated with BIM include but are not limited to cost and time savings through greater trade and design coordination, and more accurate estimating take-offs. BIM is a virtual 3D, parametric design software that allows users to store information of a model within and can be used as a communication platform between project stakeholders. Likewise, energy simulation is an integral tool for predicting and optimizing a building's performance during design. Creating energy models and running energy simulations can be a time consuming activity due to the large number of parameters and assumptions that must be addressed to achieve reasonably accurate results. However, leveraging information imbedded within Building Information Models (BIMs) has the potential to increase accuracy and reduce the amount of time required to run energy simulations and can facilitate continuous energy simulations throughout the design process, thus optimizing building performance. Although some literature exists on how design stakeholders perceive the benefits associated with leveraging BIM for energy simulation, little is known about how perceptions associated with leveraging BIM for energy simulation differ between various green design stakeholder user groups. Through an e-survey instrument, this study seeks to determine how perceptions of using BIMs to inform energy simulation differ among distinct design stakeholder groups, which include BIM-only users, energy simulation-only users and BIM and energy simulation users. Additionally, this study seeks to determine what design stakeholders perceive as the main barriers and benefits of implementing BIM-based energy simulation. Results from this study suggest that little to no correlation exists between green design stakeholders' perceptions of the value associated with using information from BIMs to inform energy simulation and their engagement level with BIM and/or energy simulation. However, green design stakeholder perceptions of the value associated with using information from BIMs to inform energy simulation and their engagement with BIM and/or energy simulation may differ between different user groups (i.e. BIM users only, energy simulation users only, and BIM and energy simulation users). For example, the BIM-only user groups appeared to have a strong positive correlation between the perceptions of the value associated with using information from BIMs to inform energy simulation and their engagement with BIM. Additionally, this study suggests that the top perceived benefits of using BIMs to inform energy simulations among green design stakeholders are: facilitation of communication, reducing of process related costs, and giving users the ability examine more design options. The main perceived barrier of using BIMs to inform energy simulations among green design stakeholders was a lack of BIM standards for model integration with multidisciplinary teams. Results from this study will help readers understand how to better implement BIM-based energy simulation while mitigating barriers and optimizing benefits. Additionally, examining discrepancies between user groups can lead the identification and improvement of shortfalls in current BIM-based energy simulation processes. Understanding how perceptions and engagement levels differ among different software user groups will help in developing a strategies for implementing BIM-based energy simulation that are tailored to each specific user group.

Research Methods in Healthcare Epidemiology and Antimicrobial Stewardship-Quasi-Experimental Designs.

PubMed

Schweizer, Marin L; Braun, Barbara I; Milstone, Aaron M

2016-10-01

Quasi-experimental studies evaluate the association between an intervention and an outcome using experiments in which the intervention is not randomly assigned. Quasi-experimental studies are often used to evaluate rapid responses to outbreaks or other patient safety problems requiring prompt, nonrandomized interventions. Quasi-experimental studies can be categorized into 3 major types: interrupted time-series designs, designs with control groups, and designs without control groups. This methods paper highlights key considerations for quasi-experimental studies in healthcare epidemiology and antimicrobial stewardship, including study design and analytic approaches to avoid selection bias and other common pitfalls of quasi-experimental studies. Infect Control Hosp Epidemiol 2016;1-6.

Research Methods in Healthcare Epidemiology and Antimicrobial Stewardship – Quasi-Experimental Designs

PubMed Central

Schweizer, Marin L.; Braun, Barbara I.; Milstone, Aaron M.

2016-01-01

Quasi-experimental studies evaluate the association between an intervention and an outcome using experiments in which the intervention is not randomly assigned. Quasi-experimental studies are often used to evaluate rapid responses to outbreaks or other patient safety problems requiring prompt non-randomized interventions. Quasi-experimental studies can be categorized into three major types: interrupted time series designs, designs with control groups, and designs without control groups. This methods paper highlights key considerations for quasi-experimental studies in healthcare epidemiology and antimicrobial stewardship including study design and analytic approaches to avoid selection bias and other common pitfalls of quasi-experimental studies. PMID:27267457

Risk Factors Associated with Injury and Mortality from Paediatric Low Speed Vehicle Incidents: A Systematic Review

PubMed Central

Paul Anthikkat, Anne; Page, Andrew; Barker, Ruth

2013-01-01

Objective. This study reviews modifiable risk factors associated with fatal and nonfatal injury from low-speed vehicle runover (LSVRO) incidents involving children aged 0–15 years. Data Sources. Electronic searches for child pedestrian and driveway injuries from the peer-reviewed literature and transport-related websites from 1955 to 2012. Study Selection. 41 studies met the study inclusion criteria. Data Extraction. A systematic narrative summary was conducted that included study design, methodology, risk factors, and other study variables. Results. The most commonly reported risk factors for LSVRO incidents included age under 5 years, male gender, and reversing vehicles. The majority of reported incidents involved residential driveways, but several studies identified other traffic and nontraffic locations. Low socioeconomic status and rental accommodation were also associated with LSVRO injury. Vehicles were most commonly driven by a family member, predominantly a parent. Conclusion. There are a number of modifiable vehicular, environmental, and behavioural factors associated with LSVRO injuries in young children that have been identified in the literature to date. Strategies relating to vehicle design (devices for increased rearward visibility and crash avoidance systems), housing design (physical separation of driveway and play areas), and behaviour (driver behaviour, supervision of young children) are discussed. PMID:23781251

Summary of Prometheus Radiation Shielding Nuclear Design Analysis

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

J. Stephens

2006-01-13

This report transmits a summary of radiation shielding nuclear design studies performed to support the Prometheus project. Together, the enclosures and references associated with this document describe NRPCT (KAPL & Bettis) shielding nuclear design analyses done for the project.

Consumption of fruit and vegetables reduces risk of pancreatic cancer: evidence from epidemiological studies.

PubMed

Wu, Qi-Jun; Wu, Lang; Zheng, Li-Qiang; Xu, Xin; Ji, Chao; Gong, Ting-Ting

2016-05-01

Observational studies have reported inconsistent results on the association between fruit and vegetable intake and the risk of pancreatic cancer. We carried out a meta-analysis of epidemiological studies to summarize available evidence. We searched PubMed, Scopus, and ISI Web of Science databases for relevant studies published until the end of January 2015. Fixed-effects and random-effects models were used to estimate the summary relative risks (RRs) and 95% confidence intervals (CIs) for the associations between fruit and vegetable intake and the risk of pancreatic cancer. A total of 15 case-control studies, eight prospective studies, and one pooled analysis fulfilled the inclusion criteria. The summary RR for the highest versus the lowest intake was 0.73 (95% CI=0.53-1.00) for fruit and vegetables, 0.73 (95% CI=0.63-0.84) for fruit, and 0.76 (95% CI=0.69-0.83) for vegetables, with significant heterogeneities (I=70.5, 55.7, and 43.0%, respectively). Inverse associations were observed in the stratified analysis by study design, although the results of prospective studies showed borderline significance, with corresponding RR=0.90 (95% CI=0.77-1.05) for fruit and vegetable intake, 0.93 (95% CI=0.83-1.03) for fruit intake, and 0.89 (95% CI=0.80-1.00) for vegetable intake. Besides, significant inverse associations were observed in the majority of other subgroup analyses by study quality, geographic location, exposure assessment method, and adjustment for potential confounders. Findings from the present meta-analysis support that fruit and vegetable intake is associated inversely with the risk of pancreatic cancer. However, study design may play a key role in the observed magnitude of the aforementioned association. Future well-designed prospective studies are warranted to confirm these findings.

Amphetamine-type stimulants and HIV infection among men who have sex with men: implications on HIV research and prevention from a systematic review and meta-analysis

PubMed Central

Thu Vu, Nga Thi; Maher, Lisa; Zablotska, Iryna

2015-01-01

Introduction HIV infections and the use of amphetamine-type stimulants (ATS) among men who have sex with men (MSM) have been increasing internationally, but the role of ATS use as a co-factor for HIV infection remains unclear. We aimed to summarize the association between ATS use and HIV infection among MSM. Methods We conducted a systematic search of MEDLINE, EMBASE, GLOBAL HEALTH and PsycINFO for relevant English, peer-reviewed articles of quantitative studies published between 1980 and 25 April 2013. Pooled estimates of the association – prevalence rate ratios (PRR, cross-sectional studies), odds ratio (OR, case-control studies) and hazard ratio (HR, longitudinal studies), with 95% Confidence Intervals (CI) – were calculated using random-effects models stratified by study design and ATS group (meth/amphetamines vs. ecstasy). We assessed the existence of publication bias in funnel plots and checked for sources of heterogeneity using meta-regression and subgroup analysis. Results We identified 6710 article titles, screened 1716 abstracts and reviewed 267 full text articles. A total of 35 publications were eligible for data abstraction and meta-analysis, resulting in 56 records of ATS use. Most studies (31/35) were conducted in high-income countries. Published studies used different research designs, samples and measures of ATS use. The pooled association between meth/amphetamine use and HIV infection was statistically significant in all three designs (PRR=1.86; 95% CI: 1.57–2.17; OR=2.73; 95% CI: 2.16–3.46 and HR=3.43; 95% CI: 2.98–3.95, respectively, for cross-sectional, case-control and longitudinal studies). Ecstasy use was not associated with HIV infection in cross-sectional studies (PRR=1.15; 95% CI: 0.88–1.49; OR=3.04; 95% CI: 1.29–7.18 and HR=2.48; 95% CI: 1.42–4.35, respectively, for cross-sectional, case-control and longitudinal studies). Results in cross-sectional studies were highly heterogeneous due to issues with ATS measurement and different sampling frames. Conclusions While meth/amphetamine use was significantly associated with HIV infection among MSM in high-income countries in all study designs, evidence of the role of ecstasy in HIV infection was lacking in cross-sectional studies. Cross-sectional study design, measurement approaches and source populations may also be important modifiers of the strength and the direction of associations. Event-specific measure of individual drug is required to establish temporal relationship between ATS use and HIV infection. HIV prevention programmes targeting MSM should consider including interventions designed to address meth/amphetamine use. PMID:25609214

A Genetically Informed Study of Associations between Family Functioning and Child Psychosocial Adjustment

ERIC Educational Resources Information Center

Schermerhorn, Alice C.; D'Onofrio, Brian M.; Turkheimer, Eric; Ganiban, Jody M.; Spotts, Erica L.; Lichtenstein, Paul; Reiss, David; Neiderhiser, Jenae M.

2011-01-01

Research has documented associations between family functioning and offspring psychosocial adjustment, but questions remain regarding whether these associations are partly due to confounding genetic factors and other environmental factors. The current study used a genetically informed approach, the Children of Twins design, to explore the…

Crime Prevention through Environmental Design (CPTED) Characteristics Associated with Violence and Safety in Middle Schools

ERIC Educational Resources Information Center

Vagi, Kevin J.; Stevens, Mark R.; Simon, Thomas R.; Basile, Kathleen C.; Carter, Sherry P.; Carter, Stanley L.

2018-01-01

Background: This study used a new Crime Prevention Through Environmental Design (CPTED) assessment tool to test the associations between physical attributes of schools and violence-related behaviors and perceptions of students. Methods: Data were collected from 4717 students from 50 middle schools. Student perceptions of risk and safety, and…

( DETROIT, MI ) STUDY DESIGN AND PRELIMINARY EXPOSURE FINDINGS ASSOCIATED WITH THE DEARS

EPA Science Inventory

The Detroit Exposure and Aerosol Research Study (DEARS) is a three-year field monitoring study initiated in 2004 that is designed to measure exposure and describe exposure relationships for air toxics, PM components, PM from specific sources, and criteria pollutants. Detroit, Mic...

Implicit Approach-Avoidance Associations for Craved Food Cues

ERIC Educational Resources Information Center

Kemps, Eva; Tiggemann, Marika; Martin, Rachel; Elliott, Mecia

2013-01-01

Implicit approach associations are well documented for substances such as alcohol, tobacco, and illicit drugs. This study reports two experiments designed to establish and modify such associations specifically in the food craving domain. Experiment 1 used a pictorial implicit association task to examine approach-avoidance associations with…

Ultra-processed Food Intake and Obesity: What Really Matters for Health-Processing or Nutrient Content?

PubMed

Poti, Jennifer M; Braga, Bianca; Qin, Bo

2017-12-01

The aim of this narrative review was to summarize and critique recent evidence evaluating the association between ultra-processed food intake and obesity. Four of five studies found that higher purchases or consumption of ultra-processed food was associated with overweight/obesity. Additional studies reported relationships between ultra-processed food intake and higher fasting glucose, metabolic syndrome, increases in total and LDL cholesterol, and risk of hypertension. It remains unclear whether associations can be attributed to processing itself or the nutrient content of ultra-processed foods. Only three of nine studies used a prospective design, and the potential for residual confounding was high. Recent research provides fairly consistent support for the association of ultra-processed food intake with obesity and related cardiometabolic outcomes. There is a clear need for further studies, particularly those using longitudinal designs and with sufficient control for confounding, to potentially confirm these findings in different populations and to determine whether ultra-processed food consumption is associated with obesity independent of nutrient content.

Partial gravity habitat study

NASA Technical Reports Server (NTRS)

Capps, Stephen; Lorandos, Jason; Akhidime, Eval; Bunch, Michael; Lund, Denise; Moore, Nathan; Murakawa, Kiosuke

1989-01-01

The purpose of this study is to investigate comprehensive design requirements associated with designing habitats for humans in a partial gravity environment, then to apply them to a lunar base design. Other potential sites for application include planetary surfaces such as Mars, variable-gravity research facilities, and a rotating spacecraft. Design requirements for partial gravity environments include locomotion changes in less than normal earth gravity; facility design issues, such as interior configuration, module diameter, and geometry; and volumetric requirements based on the previous as well as psychological issues involved in prolonged isolation. For application to a lunar base, it is necessary to study the exterior architecture and configuration to insure optimum circulation patterns while providing dual egress; radiation protection issues are addressed to provide a safe and healthy environment for the crew; and finally, the overall site is studied to locate all associated facilities in context with the habitat. Mission planning is not the purpose of this study; therefore, a Lockheed scenario is used as an outline for the lunar base application, which is then modified to meet the project needs. The goal of this report is to formulate facts on human reactions to partial gravity environments, derive design requirements based on these facts, and apply the requirements to a partial gravity situation which, for this study, was a lunar base.

Biofilm community structure and the associated drag penalties of a groomed fouling release ship hull coating.

PubMed

Hunsucker, Kelli Z; Vora, Gary J; Hunsucker, J Travis; Gardner, Harrison; Leary, Dagmar H; Kim, Seongwon; Lin, Baochuan; Swain, Geoffrey

2018-02-01

Grooming is a proactive method to keep a ship's hull free of fouling. This approach uses a frequent and gentle wiping of the hull surface to prevent the recruitment of fouling organisms. A study was designed to compare the community composition and the drag associated with biofilms formed on a groomed and ungroomed fouling release coating. The groomed biofilms were dominated by members of the Gammaproteobacteria and Alphaproteobacteria as well the diatoms Navicula, Gomphonemopsis, Cocconeis, and Amphora. Ungroomed biofilms were characterized by Phyllobacteriaceae, Xenococcaceae, Rhodobacteraceae, and the pennate diatoms Cyclophora, Cocconeis, and Amphora. The drag forces associated with a groomed biofilm (0.75 ± 0.09 N) were significantly less than the ungroomed biofilm (1.09 ± 0.06 N). Knowledge gained from this study has helped the design of additional testing which will improve grooming tool design, minimizing the growth of biofilms and thus lowering the frictional drag forces associated with groomed surfaces.

City Governments and Aging in Place: Community Design, Transportation and Housing Innovation Adoption

PubMed Central

Lehning, Amanda J.

2012-01-01

Purpose of the study: To examine the characteristics associated with city government adoption of community design, housing, and transportation innovations that could benefit older adults. Design and methods: A mixed-methods study with quantitative data collected via online surveys from 62 city planners combined with qualitative data collected via telephone interviews with a subsample of 18 survey respondents. Results: Results indicate that advocacy is an effective strategy to encourage city government adoption of these innovations. Percent of the population with a disability was positively associated, whereas percent of the population aged 65 and older was not associated or negatively associated, with innovation adoption in the regression models. Qualitative interviews suggest that younger individuals with disabilities are more active in local advocacy efforts. Implications: Results suggest that successful advocacy strategies for local government adoption include facilitating the involvement of older residents, targeting key decision makers within government, emphasizing the financial benefits to the city, and focusing on cities whose aging residents are vulnerable to disease and disability. PMID:21900505

Municipal Officials' Participation in Built Environment Policy Development in the United States.

PubMed

Lemon, Stephenie C; Goins, Karin Valentine; Schneider, Kristin L; Brownson, Ross C; Valko, Cheryl A; Evenson, Kelly R; Eyler, Amy A; Heinrich, Katie M; Litt, Jill; Lyn, Rodney; Reed, Hannah L; Tompkins, Nancy O'Hara; Maddock, Jay

2015-01-01

This study examined municipal officials' participation in built environment policy initiatives focused on land use design, transportation, and parks and recreation. Web-based cross-sectional survey. Eighty-three municipalities with 50,000 or more residents in eight states. Four hundred fifty-three elected and appointed municipal officials. Outcomes included self-reported participation in land use design, transportation, and parks and recreation policy to increase physical activity. Independent variables included respondent position; perceptions of importance, barriers, and beliefs regarding physical activity and community design and layout; and physical activity partnership participation. Multivariable logistic regression models. Compared to other positions, public health officials had lower participation in land use design (78.3% vs. 29.0%), transportation (78.1% vs. 42.1%), and parks and recreation (67.1% vs. 26.3%) policy. Perceived limited staff was negatively associated with participation in each policy initiative. Perceptions of the extent to which physical activity was considered in community design and physical activity partnership participation were positively associated with participation in each. Perceived lack of collaboration was associated with less land use design and transportation policy participation, and awareness that community design affects physical activity was associated with more participation. Perceived lack of political will was associated with less parks and recreation policy participation. Public health officials are underrepresented in built environment policy initiatives. Improving collaborations may improve municipal officials' policy participation.

The Application of Layer Theory to Design: The Control Layer

ERIC Educational Resources Information Center

Gibbons, Andrew S.; Langton, Matthew B.

2016-01-01

A theory of design layers proposed by Gibbons ("An Architectural Approach to Instructional Design." Routledge, New York, 2014) asserts that each layer of an instructional design is related to a body of theory closely associated with the concerns of that particular layer. This study focuses on one layer, the control layer, examining…

Aragon workers' health study - design and cohort description

USDA-ARS?s Scientific Manuscript database

Spain, a Mediterranean country with relatively low rates of coronary heart disease, has a high prevalence of traditional cardiovascular risk factors and is experiencing a severe epidemic of overweight/obesity. We designed the Aragon Workers' Health Study (AWHS) to characterize the factors associated...

Adolescents' Cyber Aggression Perpetration and Cyber Victimization: The Longitudinal Associations with School Functioning

ERIC Educational Resources Information Center

Wright, Michelle F.

2015-01-01

The literature on cyber aggression is advancing, revealing many risk factors associated with the involvement in these behaviors. Academic correlates, particularly academic performance, have received some attention, with few studies utilizing longitudinal designs. The present study examined these associations among 673 8th graders (51% female) from…

Design and Validation of a Rubric to Assess the Use of American Psychological Association Style in Scientific Articles

ERIC Educational Resources Information Center

Merma Molina, Gladys; Peña Alfaro, Hilda; Peña Alfaro González, Silvia Rosa

2017-01-01

In this study, the researchers will explore the process of designing and validating a rubric to evaluate the adaptation of scientific articles in the format of the "American Psychological Association" (APA). The rubric will evaluate certain aspects of the APA format that allow authors, editors, and evaluators to decide if the scientific…

Evaluation of methodology for the analysis of 'time-to-event' data in pharmacogenomic genome-wide association studies.

PubMed

Syed, Hamzah; Jorgensen, Andrea L; Morris, Andrew P

2016-06-01

To evaluate the power to detect associations between SNPs and time-to-event outcomes across a range of pharmacogenomic study designs while comparing alternative regression approaches. Simulations were conducted to compare Cox proportional hazards modeling accounting for censoring and logistic regression modeling of a dichotomized outcome at the end of the study. The Cox proportional hazards model was demonstrated to be more powerful than the logistic regression analysis. The difference in power between the approaches was highly dependent on the rate of censoring. Initial evaluation of single-nucleotide polymorphism association signals using computationally efficient software with dichotomized outcomes provides an effective screening tool for some design scenarios, and thus has important implications for the development of analytical protocols in pharmacogenomic studies.

Recommendations for Benchmarking Preclinical Studies of Nanomedicines.

PubMed

Dawidczyk, Charlene M; Russell, Luisa M; Searson, Peter C

2015-10-01

Nanoparticle-based delivery systems provide new opportunities to overcome the limitations associated with traditional small-molecule drug therapy for cancer and to achieve both therapeutic and diagnostic functions in the same platform. Preclinical trials are generally designed to assess therapeutic potential and not to optimize the design of the delivery platform. Consequently, progress in developing design rules for cancer nanomedicines has been slow, hindering progress in the field. Despite the large number of preclinical trials, several factors restrict comparison and benchmarking of different platforms, including variability in experimental design, reporting of results, and the lack of quantitative data. To solve this problem, we review the variables involved in the design of preclinical trials and propose a protocol for benchmarking that we recommend be included in in vivo preclinical studies of drug-delivery platforms for cancer therapy. This strategy will contribute to building the scientific knowledge base that enables development of design rules and accelerates the translation of new technologies. ©2015 American Association for Cancer Research.

High reprint orders in medical journals and pharmaceutical industry funding: case-control study

PubMed Central

Handel, Adam E; Patel, Sunil V; Pakpoor, Julia; Ebers, George C; Goldacre, Ben

2012-01-01

Objectives To assess the extent to which funding and study design are associated with high reprint orders. Design Case-control study. Setting Top articles by size of reprint orders in seven journals, 2002-09. Participants Lancet, Lancet Neurology, Lancet Oncology (Lancet Group), BMJ, Gut, Heart, and Journal of Neurology, Neurosurgery & Psychiatry (BMJ Group) matched to contemporaneous articles not in the list of high reprint orders. Main outcome measures Funding and design of randomised controlled trials or other study designs. Results Median reprint orders for the seven journals ranged from 3000 to 126 350. Papers with high reprint orders were more likely to be funded by the pharmaceutical industry than were control papers (industry funding versus other or none: odds ratio 8.64, 95% confidence interval 5.09 to 14.68, and mixed funding versus other or none: 3.72, 2.43 to 5.70). Conclusions Funding by the pharmaceutical industry is associated with high numbers of reprint orders. PMID:22745328

An update on the relationship between statins and physical activity.

PubMed

Panza, Gregory A; Taylor, Beth A; Thompson, Paul D

2016-09-01

This review examined studies published within the last 16 months that investigated the relationship between statins and physical activity. These recent studies suggest that statins do not adversely affect cardiorespiratory fitness, muscle strength, athletic performance, or physical activity adherence. One recent study comparing patients with statin-associated myalgia and nonstatin-using controls did report that statins are associated with a slowing of time to peak power output, increased abdominal adiposity, and insulin resistance. Statin users also had different muscle gene expression than controls, but conclusions are limited by the design of that study. Previous reports suggest that statin-associated muscle symptoms such as myalgia, cramps, and weakness occur more frequently in physically active individuals, but the recent studies we reviewed do not provide additional support for this possibility. Well-designed clinical trials are needed to determine whether different statins or statin doses evoke statin-associated muscle symptoms or muscle damage that may reduce cardiorespiratory fitness and adherence to physical activity.

Cultural differences in the experience of everyday symptoms: a comparative study of South Asian and European American women.

PubMed

Karasz, Alison; Dempsey, Kara; Fallek, Ronit

2007-12-01

This paper describes a study of medically ambiguous symptoms in two contrasting cultural groups. The study combined a qualitative, meaning-centered approach with a structured coding system and comparative design. Thirty-six South Asian immigrants and thirty-seven European Americans participated in a semistructured health history interview designed to elicit conceptual models of medically unexplained illness. The groups reported similar symptoms, but the organization of illness episodes and explanatory models associated with these episodes differed sharply. A variety of cultural variables and processes is proposed to account for observed differences, including somatization, the role of local illness categories, and the divergent core conflicts and values associated with gender roles. It is argued that the comparative design of the study provided insights that could not have been achieved through the study of a single group.

Quantifying fish habitat associated with stream simulation design culverts in northern Wisconsin

Treesearch

A. Timm; D. Higgins; J. Stanovick; R. Kolka; S. Eggert

2017-01-01

This study investigated the effects of culvert replacement design on fish habitat and fish weight by comparing substrate diversity and weight at three stream simulation (SS)-design and three bankfull and backwater (BB)-design sites on the Chequamegon-Nicolet National Forest, Wisconsin. Stream channel cross-sections, Wolman substrate particle counts, and single-pass...

Life cycle, cost, and loading characteristics of AASHO designed rigid and flexible pavements in Louisiana : final report.

DOT National Transportation Integrated Search

1989-02-01

This report represents a study undertaken to determine the life cycle, load characteristics, and associated costs of a representative sample of the oldest rigid and flexible pavements designed in Louisiana (1963-1967) using the AASHO Guide for Design...

Factors Associated with Screen Time among School-Age Children in Korea

ERIC Educational Resources Information Center

Ham, Ok Kyung; Sung, Kyung Mi; Kim, Hee Kyung

2013-01-01

The purpose of this study was to investigate the association of sociodemographic, psychosocial, and behavioral characteristics with screen time among school-age children in Korea. This study employed a nonexperimental, cross-sectional study design. A total of 370 children attending four elementary schools participated in the study. Self-report…

Associations between Mother-Child Relationship Quality and Adolescent Adjustment: Using a Genetically Controlled Design to Determine the Direction and Magnitude of Effects

ERIC Educational Resources Information Center

Guimond, Fanny-Alexandra; Laursen, Brett; Vitaro, Frank; Brendgen, Mara; Dionne, Ginette; Boivin, Michel

2016-01-01

This study used a genetically controlled design to examine the direction and the magnitude of effects in the over-time associations between perceived relationship quality with mothers and adolescent maladjustment (i.e., depressive symptoms and delinquency). A total of 163 monozygotic (MZ) twins pairs (85 female pairs, 78 male pairs) completed…

The Effects of Point-of-View Video Modeling on Symbolic Play Actions and Play-Associated Language Utterances in Preschoolers with Autism

ERIC Educational Resources Information Center

Bonnet, Lauren Kravetz

2012-01-01

This single-subject research study was designed to examine the effects of point-of-view video modeling (POVM) on the symbolic play actions and play-associated language of four preschool students with autism. A multiple baseline design across participants was conducted in order to evaluate the effectiveness of using POVM as an intervention for…

Does Childhood Anxiety Evoke Maternal Control? A Genetically Informed Study

ERIC Educational Resources Information Center

Eley, Thalia C.; Napolitano, Maria; Lau, Jennifer Y. F.; Gregory, Alice M.

2010-01-01

Background: Despite theoretical and empirical support for an association between maternal control and child anxiety, few studies have examined the origins of this association. Furthermore, none use observer-ratings of maternal control within a genetically informative design. This study addressed three questions: 1) do children who experience…

76 FR 10573 - Notice of Proposed Information Collection Requests

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-25

... study will use quasi- experimental designs to explore the relationship between magnet programs and... that (1) described the study design and full data collection activities and (2) requested approval for... associated with the fourth and fifth year of data collection necessary for the rigorous comparative...

Risk factors associated with asbestos-related diseases: a community-based case–control study

PubMed Central

2013-01-01

Background Asbestos is a first level carcinogen. However, few epidemiological studies analyse the risk and protective factors associated with asbestos-related diseases and follow up these conditions in the general population. Pleural mesothelioma, caused by inhalation of asbestos fibres at work, at home or in the environment, is the most representative asbestos-related disease. The objectives of this study are to analyse the risk and protective factors associated with asbestos-related diseases and to investigate the incidence of new clinical manifestations in patients already diagnosed with some form of ARD. Methods/Design We have designed a matched case–control study with follow up of both cohorts from a population of a health district of the Barcelona province that has been exposed to asbestos for a period of 90 years. Discussion A better understanding of asbestos-related diseases should improve i) the clinical and epidemiological follow up of patients with this condition; ii) the design of new treatment strategies; iii) and the development of preventive activities. At the end of the study, the two cohorts created in this study (affected cases and healthy controls) will constitute the basis for future research. PMID:23915043

A Study of the Factors and Conditions Associated with Graduate Enrollment Management Practitioners' Participation in Professional Development

ERIC Educational Resources Information Center

Balayan, Ariana

2016-01-01

This investigation was designed to determine the factors and conditions associated with graduate enrollment management practitioners' participation in professional development (PD) activities. The sample consisted of members of a professional association, the National Association of Graduate Admissions Professionals (NAGAP), focused solely on…

Metataxonomic Analysis of Individuals at BMI Extremes and Monozygotic Twins Discordant for BMI.

PubMed

Finnicum, Casey T; Doornweerd, Stieneke; Dolan, Conor V; Luningham, Justin M; Beck, Jeffrey J; Willemsen, Gonneke; Ehli, Erik A; Boomsma, Dorret I; Ijzerman, Richard G; Davies, Gareth E; de Geus, Eco J C

2018-06-01

The human gut microbiota has been demonstrated to be associated with a number of host phenotypes, including obesity and a number of obesity-associated phenotypes. This study is aimed at further understanding and describing the relationship between the gut microbiota and obesity-associated measurements obtained from human participants. Here, we utilize genetically informative study designs, including a four-corners design (extremes of genetic risk for BMI and of observed BMI; N = 50) and the BMI monozygotic (MZ) discordant twin pair design (N = 30), in order to help delineate the role of host genetics and the gut microbiota in the development of obesity. Our results highlight a negative association between BMI and alpha diversity of the gut microbiota. The low genetic risk/high BMI group of individuals had a lower gut microbiota alpha diversity when compared to the other three groups. Although the difference in alpha diversity between the lean and heavy groups of the BMI-discordant MZ twin design did not achieve significance, this difference was observed to be in the expected direction, with the heavier participants having a lower average alpha diversity. We have also identified nine OTUs observed to be associated with either a leaner or heavier phenotype, with enrichment for OTUs classified to the Ruminococcaceae and Oxalobacteraceae taxonomic families. Our study presents evidence of a relationship between BMI and alpha diversity of the gut microbiota. In addition to these findings, a number of OTUs were found to be significantly associated with host BMI. These findings may highlight separate subtypes of obesity, one driven by genetic factors, the other more heavily influenced by environmental factors.

A review of hospital characteristics associated with improved performance.

PubMed

Brand, Caroline A; Barker, Anna L; Morello, Renata T; Vitale, Michael R; Evans, Sue M; Scott, Ian A; Stoelwinder, Johannes U; Cameron, Peter A

2012-10-01

The objective of this review was to critically appraise the literature relating to associations between high-level structural and operational hospital characteristics and improved performance. The Cochrane Library, MEDLINE (Ovid), CINAHL, proQuest and PsychINFO were searched for articles published between January 1996 and May 2010. Reference lists of included articles were reviewed and key journals were hand searched for relevant articles. and data extraction Studies were included if they were systematic reviews or meta-analyses, randomized controlled trials, controlled before and after studies or observational studies (cohort and cross-sectional) that were multicentre, comparative performance studies. Two reviewers independently extracted data, assigned grades of evidence according to the Australian National Health and Medical Research Council guidelines and critically appraised the included articles. Data synthesis Fifty-seven studies were reported within 12 systematic reviews and 47 observational articles. There was heterogeneity in use and definition of performance outcomes. Hospital characteristics investigated were environment (incentives, market characteristics), structure (network membership, ownership, teaching status, geographical setting, service size) and operational design (innovativeness, leadership, organizational culture, public reporting and patient safety practices, information technology systems and decision support, service activity and planning, workforce design, staff training and education). The strongest evidence for an association with overall performance was identified for computerized physician order entry systems. Some evidence supported the associations with workforce design, use of financial incentives, nursing leadership and hospital volume. There is limited, mainly low-quality evidence, supporting the associations between hospital characteristics and healthcare performance. Further characteristic-specific systematic reviews are indicated.

Security Implications of Physical Design Attributes in the Emergency Department.

PubMed

Pati, Debajyoti; Pati, Sipra; Harvey, Thomas E

2016-07-01

Security, a subset of safety, is equally important in the efficient delivery of patient care. The emergency department (ED) is susceptible to violence creating concerns for the safety and security of patients, staff, and visitors and for the safe and efficient delivery of care. Although there is an implicit and growing recognition of the role of the physical environment, interventions typically have been at the microlevel. The objective of this study was to identify physical design attributes that potentially influence safety and efficiency of ED operations. An exploratory, qualitative research design was adopted to examine the efficiency and safety correlates of ED physical design attributes. The study comprised a multimeasure approach involving multidisciplinary gaming, semistructured interviews, and touring interviews of frontline staff in four EDs at three hospital systems across three states. Five macro physical design attributes (issues that need to be addressed at the design stage and expensive to rectify once built) emerged from the data as factors substantially associated with security issues. They are design issues pertaining to (a) the entry zone, (b) traffic management, (c) patient room clustering, (d) centralization versus decentralization, and (e) provisions for special populations. Data from this study suggest that ED security concerns are generally associated with three sources: (a) gang-related violence, (b) dissatisfied patients, and (c) behavioral health patients. Study data show that physical design has an important role in addressing the above-mentioned concerns. Implications for ED design are outlined in the article. © The Author(s) 2016.

PRELIMINARY REPORT ON NATIONWIDE STUDY OF DRINKING WATER AND CARDIOVASCULAR DISEASES

EPA Science Inventory

This study was designed to further investigate the association(s) of cardiovascular diseases and drinking water constituents. A sample of 4200 adults were randomly selected from 35 geographic areas to represent the civilian noninstitutionalized population of the contiguous United...

Variant-aware saturating mutagenesis using multiple Cas9 nucleases identifies regulatory elements at trait-associated loci.

PubMed

Canver, Matthew C; Lessard, Samuel; Pinello, Luca; Wu, Yuxuan; Ilboudo, Yann; Stern, Emily N; Needleman, Austen J; Galactéros, Frédéric; Brugnara, Carlo; Kutlar, Abdullah; McKenzie, Colin; Reid, Marvin; Chen, Diane D; Das, Partha Pratim; A Cole, Mitchel; Zeng, Jing; Kurita, Ryo; Nakamura, Yukio; Yuan, Guo-Cheng; Lettre, Guillaume; Bauer, Daniel E; Orkin, Stuart H

2017-04-01

Cas9-mediated, high-throughput, saturating in situ mutagenesis permits fine-mapping of function across genomic segments. Disease- and trait-associated variants identified in genome-wide association studies largely cluster at regulatory loci. Here we demonstrate the use of multiple designer nucleases and variant-aware library design to interrogate trait-associated regulatory DNA at high resolution. We developed a computational tool for the creation of saturating-mutagenesis libraries with single or multiple nucleases with incorporation of variants. We applied this methodology to the HBS1L-MYB intergenic region, which is associated with red-blood-cell traits, including fetal hemoglobin levels. This approach identified putative regulatory elements that control MYB expression. Analysis of genomic copy number highlighted potential false-positive regions, thus emphasizing the importance of off-target analysis in the design of saturating-mutagenesis experiments. Together, these data establish a widely applicable high-throughput and high-resolution methodology to identify minimal functional sequences within large disease- and trait-associated regions.

Chronic kidney disease-associated pruritus: impact on quality of life and current management challenges

PubMed Central

Shirazian, Shayan; Aina, Olufemi; Park, Youngjun; Chowdhury, Nawsheen; Leger, Kathleen; Hou, Linle; Miyawaki, Nobuyuki; Mathur, Vandana S

2017-01-01

Chronic kidney disease-associated pruritus (CKD-aP) is a distressing, often overlooked condition in patients with CKD and end-stage renal disease. It affects ~40% of patients with end-stage renal disease and has been associated with poor quality of life, poor sleep, depression, and mortality. Prevalence estimates vary based on the instruments used to diagnose CKD-aP, and standardized diagnostic instruments are sorely needed. Treatment studies have often yielded conflicting results. This is likely related to studies that are limited by small sample size, flawed designs, and nonstandardized diagnostic instruments. Several large well-designed treatment trials have recently been completed and may soon influence CKD-aP management. PMID:28176969

System analysis study of space platform and station accommodations for life sciences research facilities. Volume 1: Executive summary. Phase A: Conceptual design and programmatics

NASA Technical Reports Server (NTRS)

1985-01-01

The study was conducted in 3 parts over a 3 year period. The study schedule and the documentation associated with each study part is given. This document summarized selected study results from the conceptual design and programmatics segment of the effort. The objectives were: (1) to update requirements and tradeoffs and develop a detailed design and mission requirements document; (2) to develop conceptual designs and mission descriptions; and (3) to develop programmatic, i.e., work breakdown structure and work breakdown structure dictionary, estimated cost, and implementing plans and schedules.

75 FR 73104 - Clinical Development Programs for Sedation Products; Request for Assistance

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-29

... sedation claims? Would dose-escalation comparative trial designs be useful in studying sedation products? 5... understanding the physiology of sedation and clinical trial design issues related to the development of sedation... to procedural and intensive care unit (ICU) sedation, as well as associated clinical trial design...

Two decades (1993-2012) of adult intensive care unit design: a comparative study of the physical design features of the best practice examples.

PubMed

Rashid, Mahbub

2014-01-01

In 2006, Critical Care Nursing Quarterly published a study of the physical design features of a set of best practice example adult intensive care units (ICUs). These adult ICUs were awarded between 1993 and 2003 by the Society of Critical Care Medicine (SCCM), the American Association of Critical-Care Nurses, and the American Institute of Architects/Academy of Architecture for Health for their efforts to promote the critical care unit environment through design. Since 2003, several more adult ICUs were awarded by the same organizations for similar efforts. This study includes these newer ICUs along with those of the previous study to cover a period of 2 decades from 1993 to 2012. Like the 2006 study, this study conducts a systematic content analysis of the materials submitted by the award-winning adult ICUs. On the basis of the analysis, the study compares the 1993-2002 and 2003-2012 adult ICUs in relation to construction type, unit specialty, unit layout, unit size, patient room size and design, support and service area layout, and family space design. The study also compares its findings with the 2010 Guidelines for Design and Construction of Health Care Facilities of the Facility Guidelines Institute and the 2012 Guidelines for Intensive Care Unit Design of the SCCM. The study indicates that the award-winning ICUs of both decades used several design features that were associated with positive outcomes in research studies. The study also indicates that the award-winning ICUs of the second decade used more evidence-based design features than those of the first decades. In most cases, these ICUs exceeded the requirements of the Facility Guidelines Institute Guidelines to meet those of the SCCM Guidelines. Yet, the award-winning ICUs of both decades also used several features that had very little or no supporting research evidence. Since they all were able to create an optimal critical care environment for which they were awarded, having knowledge of the physical design of these award-winning ICUs may help design better ICUs.

Instructional Design and Professional Informal Learning: Practices, Tensions, and Ironies

ERIC Educational Resources Information Center

Yanchar, Stephen C.; Hawkley, Melissa N.

2015-01-01

This qualitative study explored the nature of informal learning in professional instructional designers' everyday work activities. Based on intensive interviews with six full-time practitioners, and using a hermeneutic form of data analysis, this study produced seven themes concerning the practices, tensions, and ironies associated with this…

A Population-Based Study of Preschoolers' Food Neophobia and Its Associations with Food Preferences

ERIC Educational Resources Information Center

Russell, Catherine Georgina; Worsley, Anthony

2008-01-01

Objective: This cross-sectional study was designed to investigate the relationships between food preferences, food neophobia, and children's characteristics among a population-based sample of preschoolers. Design: A parent-report questionnaire. Setting: Child-care centers, kindergartens, playgroups, day nurseries, and swimming centers. Subjects:…

Domestic Violence Assessments in the Child Advocacy Center

ERIC Educational Resources Information Center

Thackeray, Jonathan D.; Scribano, Philip V.; Rhoda, Dale

2010-01-01

Objective: This study was designed to identify the frequency, methods, and practices of universal assessments for domestic violence (DV) within child advocacy centers (CACs) and determine which factors are associated with CACs that conduct universal DV assessments. Methods: The study design was a cross-sectional, web-based survey distributed to…

The impact of extracurricular activities participation on youth delinquent behaviors: An instrumental variables approach.

PubMed

Han, Sehee; Lee, Jonathan; Park, Kyung-Gook

2017-07-01

The purpose of this study was to examine the association between extracurricular activities (EA) participation and youth delinquency while tackling an endogeneity problem of EA participation. Using survey data of 12th graders in South Korea (n = 1943), this study employed an instrumental variables approach to address the self-selection problem of EA participation as the data for this study was based on an observational study design. We found a positive association between EA participation and youth delinquency based on conventional regression analysis. By contrast, we found a negative association between EA participation and youth delinquency based on an instrumental variables approach. These results indicate that caution should be exercised when we interpret the effect of EA participation on youth delinquency based on observational study designs. Copyright © 2017 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Academic and Family Conditions Associated with Intrinsic Academic Motivation in Japanese Medical Students: A Pilot Study

ERIC Educational Resources Information Center

Tanaka, Masaaki; Watanabea, Yasuyoshi

2012-01-01

Objective: Intrinsic academic motivation is one of the most important psychological concepts in education, and it is related to academic outcomes in medical students. This study examined the relationships between academic and family conditions and intrinsic academic motivation. Design: Cross-sectional design. Setting: The study group consisted of…

Industrial Exposures at Birth are Associated with Reduced Forced Vital Capacity in Childhood

EPA Science Inventory

Rationale: Previous studies have reported associations of ambient air pollutant exposures with childhood decrements in lung volumes. While the current study was designed primarily to examine traffic exposures, we also examined the impact of other early life exposures on pulmonary...

Design Research and the Solo Higher Degree Research Student: Strategies to Embed Trustworthiness and Validity into the Research Design

ERIC Educational Resources Information Center

Kennedy-Clark, Shannon

2012-01-01

This paper puts forward a set of criteria for ensuring trustworthiness in design research studies undertaken by Higher Degree Research (HDR) students. Design research is aimed at exploring educational problems and refining theory and practice by defining a pedagogical outcome and is a methodological approach often associated with the Learning…

Replication of an association of variation in the FOXO3A gene with human longevity using both case–control and longitudinal data

PubMed Central

Soerensen, Mette; Dato, Serena; Christensen, Kaare; McGue, Matt; Stevnsner, Tinna; Bohr, Vilhelm A.; Christiansen, Lene

2010-01-01

Summary Genetic variation in FOXO3A has previously been associated with human longevity. Studies published so far have been case–control studies and hence vulnerable to bias introduced by cohort effects. In this study we extended the previous findings in the cohorts of oldest old Danes (the Danish 1905 cohort, N = 1089) and middle-aged Danes (N = 736), applying a longitudinal study design as well as the case–control study design. Fifteen SNPs were chosen in order to cover the known common variation in FOXO3A. Comparing SNP frequencies in the oldest old with middle-aged individuals, we found association (after correction for multiple testing) of eight SNPs; 4 (rs13217795, rs2764264, rs479744, and rs9400239) previously reported to be associated with longevity and four novel SNPs (rs12206094, rs13220810, rs7762395, and rs9486902 (corrected P-values 0.001–0.044). Moreover, we found association of the haplotypes TAC and CAC of rs9486902, rs10499051, and rs12206094 (corrected P-values: 0.01–0.03) with longevity. Finally, we here present data applying a longitudinal study design; when using follow-up survival data on the oldest old in a longitudinal analysis, we found no SNPs to remain significant after the correction for multiple testing (Bonferroni correction). Hence, our results support and extent the proposed role of FOXO3A as a candidate longevity gene for survival from younger ages to old age, yet not during old age. PMID:20849522

Acculturation, Medication Adherence, Lifestyle Behaviors, and Blood Pressure Control Among Arab Americans

PubMed Central

Tailakh, Ayman K.; Evangelista, Lorraine S.; Morisky, Donald E.; Mentes, Janet C.; Pike, Nancy A.; Phillips, Linda R.

2015-01-01

Purpose The aim of this study was to examine the relationship between acculturation, medication adherence, lifestyle behaviors (e.g., physical activity, nutrition, weight control), and blood pressure control among hypertensive Arab Americans. Design The study utilized a cross-sectional descriptive design. A convenience sample of 126 participants completed questionnaires and had measures of blood pressure, weight, and height. Forty-six participants were hypertensive and were included in the analysis. Results Only 29.2% of participants reported high medication adherence. High medication adherence was associated with lower diastolic blood pressure, eating a healthy diet, and following lifestyle modifications. Acculturation was significantly associated with physical activity and body mass index. Conclusion Our study found that acculturated participants were more adherent to medications and physical activity and had better blood pressure control. Further studies are needed to explore how acculturation improves adherence and what factors contribute to better adherence in order to design culturally sensitive interventions. PMID:24848347

Factors influencing increased expertise for a sustainable workforce at a research centre in South Africa

PubMed Central

Draper, H. R.; Enarson, D. A.; Beyers, N.; Claassens, M.

2014-01-01

Setting: The Desmond Tutu Tuberculosis (TB) Centre (DTTC), Stellenbosch University, South Africa. Objectives: 1) To determine whether access to designated funding is associated with the development of expertise in employees, and 2) which other factors are associated with the development of expertise in employees. Design: This was a retrospective study. The target population consisted of all employees at the DTTC during the period 1 January 2004 to 31 December 2011. Improvement in expertise during employment was the primary outcome; the secondary outcome was an increase in educational level linked to the National Qualifications Framework. Results: There was no association between access to funding and expertise development, but an association between the number of months employed and improvement of expertise during employment was observed (OR 1.03, 95%CI 1.02–1.04, P < 0.001), controlling for age at appointment, sex, access to designated funding and education level. Conclusion: The study shows that almost a third of employees increased their expertise, more than 90% had access to designated funding and personnel employed for a longer duration were more likely to experience improvements in expertise. We encourage research organisations in low- and middle-income countries to implement strategies to retain employees in order to build their expertise. PMID:26400709

A Genetically Informed Study of the Processes Underlying the Association between Parental Marital Instability and Offspring Adjustment

ERIC Educational Resources Information Center

D'Onofrio, Brian M.; Turkheimer, Eric; Emery, Robert E.; Slutske, Wendy S.; Heath, Andrew C.; Madden, Pamela A.; Martin, Nicholas G.

2006-01-01

Parental divorce is associated with problematic offspring adjustment, but the relation may be due to shared genetic or environmental factors. One way to test for these confounds is to study offspring of twins discordant for divorce. The current analyses used this design to separate the mechanisms responsible for the association between parental…

Design data needs modular high-temperature gas-cooled reactor. Revision 2

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

NONE

1987-03-01

The Design Data Needs (DDNs) provide summary statements for program management, of the designer`s need for experimental data to confirm or validate assumptions made in the design. These assumptions were developed using the Integrated Approach and are tabulated in the Functional Analysis Report. These assumptions were also necessary in the analyses or trade studies (A/TS) to develop selections of hardware design or design requirements. Each DDN includes statements providing traceability to the function and the associated assumption that requires the need.

Association between circulating vitamin K1 and coronary calcium progression in community-dwelling adults: the Multi-Ethnic Study of Atherosclerosis

USDA-ARS?s Scientific Manuscript database

While animal studies found vitamin K treatment reduced vascular calcification, human data are limited. Using a case-cohort design, we determined the association between vitamin K status and coronary artery calcium (CAC) progression in the Multi-ethnic Study of Atherosclerosis. Serum phylloquinone (v...

Avoiding false discoveries in association studies.

PubMed

Sabatti, Chiara

2007-01-01

We consider the problem of controlling false discoveries in association studies. We assume that the design of the study is adequate so that the "false discoveries" are potentially only because of random chance, not to confounding or other flaws. Under this premise, we review the statistical framework for hypothesis testing and correction for multiple comparisons. We consider in detail the currently accepted strategies in linkage analysis. We then examine the underlying similarities and differences between linkage and association studies and document some of the most recent methodological developments for association mapping.

Meta-Analysis of the Association between Tea Intake and the Risk of Cognitive Disorders

PubMed Central

Ma, Qing-Ping; Huang, Chen; Cui, Qiao-Yun; Yang, Ding-Jun; Sun, Kang; Chen, Xuan; Li, Xing-Hui

2016-01-01

Background Alzheimer’s disease is a common neurodegenerative disorder in elderly. This study was aimed to systematically evaluate the association between tea intake and the risk of cognitive disorders by meta-analysis. Methods and Findings PubMed, Embase and Wanfang databases were systematically searched and a total of 26 observational studies were included in this study. Odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were calculated and pooled by using fixed or random effects models according to the degree of heterogeneity. Results The overall pooled analysis indicated that tea intake could significantly reduce the risk of cognitive disorders (OR = 0.65, 95%CI = 0.58–0.73). Subgroup analyses were conducted based on study design, population, frequency of tea drinking and type of cognitive disorders. The results showed that tea drinking was significantly associated with the reduced incidence of cognitive disorders in all of subgroups based on study design and frequency of tea drinking. In particular, tea drinking was inversely associated with the risk of cognitive impairment (CoI), mild cognitive impairment (MCI), cognitive decline and ungrouped cognitive disorders. Moreover, for population subgroups, the significant association was only found in Chinese people. Conclusion Our study suggests that daily tea drinking is associated with decreased risk of CoI, MCI and cognitive decline in the elderly. However, the association between tea intake and Alzheimer’s disease remains elusive. PMID:27824892

Children's choice: Color associations in children's safety sign design.

PubMed

Siu, Kin Wai Michael; Lam, Mei Seung; Wong, Yi Lin

2017-03-01

Color has been more identified as a key consideration in ergonomics. Color conveys messages and is an important element in safety signs, as it provides extra information to users. However, very limited recent research has focused on children and their color association in the context of safety signs. This study thus examined how children use colors in drawing different safety signs and how they associate colors with different concepts and objects that appear in safety signs. Drawing was used to extract children's use of color and the associations they made between signs and colors. The child participants were given 12 referents of different safety signs and were asked to design and draw the signs using different colored felt-tip pens. They were also asked to give reasons for their choices of colors. Significant associations were found between red and 'don't', orange and 'hands', and blue and 'water'. The child participants were only able to attribute the reasons for the use of yellow, green, blue and black through concrete identification and concrete association, and red through abstract association. The children's use of color quite differs from that shown in the ISO registered signs. There is a need to consider the use of colors carefully when designing signs specifically for children. Sign designers should take children's color associations in consideration and be aware if there are any misunderstandings. Copyright © 2016 Elsevier Ltd. All rights reserved.

Implementation and value of using a split-plot reader design in a study of digital breast tomosynthesis in a breast cancer assessment clinic

NASA Astrophysics Data System (ADS)

Mall, Suneeta; Brennan, Patrick C.; Mello-Thoms, Claudia

2015-03-01

The rapid evolution in medical imaging has led to an increased number of recurrent trials, primarily to ensure that the efficacy of new imaging techniques is known. The cost associated with time and resources in conducting such trials is usually high. The recruitment of participants, in a medium to large reader study, is often very challenging as the demanding number of cases discourages involvement with the trial. We aim to evaluate the efficacy of Digital Breast Tomosynthesis (DBT) in a recall assessment clinic in Australia in a prospective multi-reader-multi-case (MRMC) trial. Conducting such a study with the more commonly used fully crossed MRMC study design would require more cases and more cases read per reader, which was not viable in our setting. With an aim to perform a cost effective yet statistically efficient clinical trial, we evaluated alternative study designs, particularly the alternative split-plot MRMC study design and compared and contrasted it with more commonly used fully crossed MRMC study design. Our results suggest that `split-plot', an alternative MRMC study design, could be very beneficial for medium to large clinical trials and the cost associated with conducting such trials can be greatly reduced without adversely effecting the variance of the study. We have also noted an inverse dependency between number of required readers and cases to achieve a target variance. This suggests that split-plot could also be very beneficial for studies that focus on cases that are hard to procure or readers that are hard to recruit. We believe that our results may be relevant to other researchers seeking to design a medium to large clinical trials.

Association between bibliometric parameters, reporting and methodological quality of randomised controlled trials in vascular and endovascular surgery.

PubMed

Hajibandeh, Shahab; Hajibandeh, Shahin; Antoniou, George A; Green, Patrick A; Maden, Michelle; Torella, Francesco

2017-04-01

Purpose We aimed to investigate association between bibliometric parameters, reporting and methodological quality of vascular and endovascular surgery randomised controlled trials. Methods The most recent 75 and oldest 75 randomised controlled trials published in leading journals over a 10-year period were identified. The reporting quality was analysed using the CONSORT statement, and methodological quality with the Intercollegiate Guidelines Network checklist. We used exploratory univariate and multivariable linear regression analysis to investigate associations. Findings Bibliometric parameters such as type of journal, study design reported in title, number of pages; external funding, industry sponsoring and number of citations are associated with reporting quality. Moreover, parameters such as type of journal, subject area and study design reported in title are associated with methodological quality. Conclusions The bibliometric parameters of randomised controlled trials may be independent predictors for their reporting and methodological quality. Moreover, the reporting quality of randomised controlled trials is associated with their methodological quality and vice versa.

Elevated Social Anxiety among Early Maturing Girls

ERIC Educational Resources Information Center

Blumenthal, Heidemarie; Leen-Feldner, Ellen W.; Babson, Kimberly A.; Gahr, Jessica L.; Trainor, Casey D.; Frala, Jamie L.

2011-01-01

Adolescence is a key period in terms of the development of anxiety psychopathology. An emerging literature suggests that early pubertal maturation is associated with enhanced vulnerability for anxiety symptomatology, although few studies have examined this association with regard to social anxiety. Accordingly, the current study was designed to…

Impact of ambient air pollution on physical activity among adults: a systematic review and meta-analysis.

PubMed

An, Ruopeng; Zhang, Sheng; Ji, Mengmeng; Guan, Chenghua

2018-03-01

This study systematically reviewed literature regarding the impact of ambient air pollution on physical activity among children and adults. Keyword and reference search was conducted in PubMed and Web of Science to systematically identify articles meeting all of the following criteria - study designs: interventions or experiments, retrospective or prospective cohort studies, cross-sectional studies, and case-control studies; subjects: adults; exposures: specific air pollutants and overall air quality; outcomes: physical activity and sedentary behaviour; article types: peer-reviewed publications; and language: articles written in English. Meta-analysis was performed to estimate the pooled effect size of ambient PM 2.5 air pollution on physical inactivity. Seven studies met the inclusion criteria. Among them, six were conducted in the United States, and one was conducted in the United Kingdom. Six adopted a cross-sectional study design, and one used a prospective cohort design. Six had a sample size larger than 10,000. Specific air pollutants assessed included PM 2.5 , PM 10 , O 3 , and NO x , whereas two studies focused on overall air quality. All studies found air pollution level to be negatively associated with physical activity and positively associated with leisure-time physical inactivity. Study participants, and particularly those with respiratory disease, self-reported a reduction in outdoor activities to mitigate the detrimental impact of air pollution. Meta-analysis revealed a one unit (μg/m 3 ) increase in ambient PM 2.5 concentration to be associated with an increase in the odds of physical inactivity by 1.1% (odds ratio = 1.011; 95% confidence interval = 1.001, 1.021; p-value < .001) among US adults. Existing literature in general suggested that air pollution discouraged physical activity. Current literature predominantly adopted a cross-sectional design and focused on the United States. Future studies are warranted to implement a longitudinal study design and evaluate the impact of air pollution on physical activity in heavily polluted developing countries.

Roadmap for the protection of disaster research participants: findings from the World Trade Center Evacuation Study.

PubMed

Qureshi, Kristine A; Gershon, Robyn R M; Smailes, Elizabeth; Raveis, Victoria H; Murphy, Bridgette; Matzner, Frederick; Fleischman, Alan R

2007-01-01

This report addresses the development, implementation, and evaluation of a protocol designed to protect participants from inadvertent emotional harm or further emotional trauma due to their participation in the World Trade Center Evacuation (WTCE) Study research project. This project was designed to identify the individual, organizational, and structural (environmental) factors associated with evacuation from the World Trade Center Towers 1 and 2 on 11 September 2001. Following published recommended practices for protecting potentially vulnerable disaster research participants, protective strategies and quality assurance processes were implemented and evaluated, including an assessment of the impact of participation on study subjects enrolled in the qualitative phase of the WTCE Study. The implementation of a protocol designed to protect disaster study participants from further emotional trauma was feasible and effective in minimizing risk and monitoring for psychological injury associated with study participation. Details about this successful strategy provide a roadmap that can be applied in other post-disaster research investigations.

Observational Studies: Cohort and Case-Control Studies

PubMed Central

Song, Jae W.; Chung, Kevin C.

2010-01-01

Observational studies are an important category of study designs. To address some investigative questions in plastic surgery, randomized controlled trials are not always indicated or ethical to conduct. Instead, observational studies may be the next best method to address these types of questions. Well-designed observational studies have been shown to provide results similar to randomized controlled trials, challenging the belief that observational studies are second-rate. Cohort studies and case-control studies are two primary types of observational studies that aid in evaluating associations between diseases and exposures. In this review article, we describe these study designs, methodological issues, and provide examples from the plastic surgery literature. PMID:20697313

Evaluation of load carriage systems used by active duty police officers: Relative effects on walking patterns and perceived comfort.

PubMed

Ramstrand, Nerrolyn; Zügner, Roland; Larsen, Louise Bæk; Tranberg, Roy

2016-03-01

This study aimed to examine the effects of two different load carriage systems on gait kinematics, temporospatial gait parameters and self-reported comfort in Swedish police. 21 active duty police officers were recruited for this crossover study design. Biomechanical and self-report data was collected on two testing occasions. On occasion 1, three dimensional kinematic data was collected while police wore a/no equipment (control), b/their standard issues belt and ballistic protection vest and c/a load bearing vest with ballistic protection vest. Police then wore the load bearing vest for a minimum of 3 months before the second testing occasion. The load bearing vest was associated with a significant reduction in range of motion of the trunk, pelvis and hip joints. Biomechanical changes associated with the load bearing vest appeared to reduce with increased wear time. In both the standard issue belt condition and the load bearing vest condition, police walked with the arms held in a significantly greater degree of abduction. Self-report data indicated a preference for the load bearing vest. The two load carriage designs tested in this study were found to significantly alter gait kinematics. The load bearing vest design was associated with the greatest number of kinematic compensations however these reduced over time as police became more accustomed to the design. Results from this study do not support selection of one load carriage design over the other and providing individuals with the option to choose a load carriage design is considered appropriate. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Practicing Accounting Profession Criterial Skills in the Classroom: A Study of Collaborative Testing and the Impact on Final Exam Scores

ERIC Educational Resources Information Center

VanderLaan, Ski R.

2010-01-01

This mixed methods study (Creswell, 2008) was designed to test the influence of collaborative testing on learning using a quasi-experimental approach. This study used a modified embedded mixed method design in which the qualitative and quantitative data, associated with the secondary questions, provided a supportive role in a study based primarily…

Project-Based Pedagogy for the Facilitation of Webpage Design

ERIC Educational Resources Information Center

Jakovljevic, Maria; Ankiewicz, Piet

2016-01-01

Real issues of web design and development include many problem-solving tasks. There are, however, some inadequacies associated with the implementation of appropriate pedagogy for organised and structured instruction that supports the rational problem-solving paradigm. The purpose of this article is to report on a study for the design and…

Calcium intake, serum vitamin D and obesity in children: is there an association?

PubMed Central

da Cunha, Kelly Aparecida; Magalhães, Elma Izze da Silva; Loureiro, Laís Monteiro Rodrigues; Sant'Ana, Luciana Ferreira da Rocha; Ribeiro, Andréia Queiroz; de Novaes, Juliana Farias

2015-01-01

OBJECTIVE: To evaluate the association between calcium intake and serum vitamin D levels and childhood obesity by an integrative review. DATA SOURCE: The research was conducted in the databases PubMed/medLine, Science Direct and SciELO with 2001 to 2014 publications. We used the combined terms in English: ''children'' and ''calcium'' or ''children'' and ''vitamin D'' associated with the descriptors: ''obesity'', ''adiposity'' or ''body fat'' for all bases. Cross-sectional and cohort studies, as well as clinical trials, were included. Review articles or those that that have not addressed the association of interest were excluded. DATA SYNTHESIS: Eight articles were part of this review, five of which were related to calcium and three to vitamin D. Most studies had a longitudinal design. The analyzed studies found an association between calcium intake and obesity, especially when age and sex were considered. Inverse relationship between serum vitamin D and measures of adiposity in children has been observed and this association was influenced by the sex of the patient and by the seasons of the year. CONCLUSIONS: The studies reviewed showed an association between calcium and vitamin D with childhood obesity. Considering the possible protective effect of these micronutrients in relation to childhood obesity, preventive public health actions should be designed, with emphasis on nutritional education. PMID:25890445

User-centered design to improve clinical decision support in primary care.

PubMed

Brunner, Julian; Chuang, Emmeline; Goldzweig, Caroline; Cain, Cindy L; Sugar, Catherine; Yano, Elizabeth M

2017-08-01

A growing literature has demonstrated the ability of user-centered design to make clinical decision support systems more effective and easier to use. However, studies of user-centered design have rarely examined more than a handful of sites at a time, and have frequently neglected the implementation climate and organizational resources that influence clinical decision support. The inclusion of such factors was identified by a systematic review as "the most important improvement that can be made in health IT evaluations." (1) Identify the prevalence of four user-centered design practices at United States Veterans Affairs (VA) primary care clinics and assess the perceived utility of clinical decision support at those clinics; (2) Evaluate the association between those user-centered design practices and the perceived utility of clinical decision support. We analyzed clinic-level survey data collected in 2006-2007 from 170 VA primary care clinics. We examined four user-centered design practices: 1) pilot testing, 2) provider satisfaction assessment, 3) formal usability assessment, and 4) analysis of impact on performance improvement. We used a regression model to evaluate the association between user-centered design practices and the perceived utility of clinical decision support, while accounting for other important factors at those clinics, including implementation climate, available resources, and structural characteristics. We also examined associations separately at community-based clinics and at hospital-based clinics. User-centered design practices for clinical decision support varied across clinics: 74% conducted pilot testing, 62% conducted provider satisfaction assessment, 36% conducted a formal usability assessment, and 79% conducted an analysis of impact on performance improvement. Overall perceived utility of clinical decision support was high, with a mean rating of 4.17 (±.67) out of 5 on a composite measure. "Analysis of impact on performance improvement" was the only user-centered design practice significantly associated with perceived utility of clinical decision support, b=.47 (p<.001). This association was present in hospital-based clinics, b=.34 (p<.05), but was stronger at community-based clinics, b=.61 (p<.001). Our findings are highly supportive of the practice of analyzing the impact of clinical decision support on performance metrics. This was the most common user-centered design practice in our study, and was the practice associated with higher perceived utility of clinical decision support. This practice may be particularly helpful at community-based clinics, which are typically less connected to VA medical center resources. Published by Elsevier B.V.

MetaGenyo: a web tool for meta-analysis of genetic association studies.

PubMed

Martorell-Marugan, Jordi; Toro-Dominguez, Daniel; Alarcon-Riquelme, Marta E; Carmona-Saez, Pedro

2017-12-16

Genetic association studies (GAS) aims to evaluate the association between genetic variants and phenotypes. In the last few years, the number of this type of study has increased exponentially, but the results are not always reproducible due to experimental designs, low sample sizes and other methodological errors. In this field, meta-analysis techniques are becoming very popular tools to combine results across studies to increase statistical power and to resolve discrepancies in genetic association studies. A meta-analysis summarizes research findings, increases statistical power and enables the identification of genuine associations between genotypes and phenotypes. Meta-analysis techniques are increasingly used in GAS, but it is also increasing the amount of published meta-analysis containing different errors. Although there are several software packages that implement meta-analysis, none of them are specifically designed for genetic association studies and in most cases their use requires advanced programming or scripting expertise. We have developed MetaGenyo, a web tool for meta-analysis in GAS. MetaGenyo implements a complete and comprehensive workflow that can be executed in an easy-to-use environment without programming knowledge. MetaGenyo has been developed to guide users through the main steps of a GAS meta-analysis, covering Hardy-Weinberg test, statistical association for different genetic models, analysis of heterogeneity, testing for publication bias, subgroup analysis and robustness testing of the results. MetaGenyo is a useful tool to conduct comprehensive genetic association meta-analysis. The application is freely available at http://bioinfo.genyo.es/metagenyo/ .

Drug development for exceptionally rare metabolic diseases: challenging but not impossible.

PubMed

Putzeist, Michelle; Mantel-Teeuwisse, Aukje K; Wied, Christine C Gispen-de; Hoes, Arno W; Leufkens, Hubert G M; de Vrueh, Remco L A

2013-11-15

We studied to what extent the level of scientific knowledge on exceptionally rare metabolic inherited diseases and their potential orphan medicinal products is associated with sponsors deciding to apply for an orphan designation at the US Food and Drug Administration (FDA) or the European Medicines Agency (EMA). All metabolic diseases with a genetic cause and prevalence of less than 10 patients per 1 million of the population were selected from the 'Orphanet database of Rare diseases'. The outcome of interest was the application for an orphan designation at FDA or EMA. The level of publicly available knowledge of the disease and drug candidate before an orphan designation application was defined as whether the physiological function corresponding with the pathologic gene and initiation of the pathophysiological pathway was known, whether an appropriate animal study was identified for the disease, whether preclinical proof of concept was ascertained and the availability of data in humans. Other determinants included in the study were metabolic disease class, the prevalence of the disease, prognosis and time of first description of the disease in the literature. Univariate relative risks (RRs) and 95% confidence intervals (CIs) of an orphan designation application were calculated for each of these determinants. In addition, a multivariate Cox regression analysis was conducted (Forward LR). In total, 166 rare metabolic genetic diseases were identified and included in the analysis. For only 42 (25%) of the diseases an orphan designation application was submitted at either FDA or EMA before January 2012. The multivariate analysis identified preclinical proof of concept of a potential medicinal product as major knowledge related determinant associated with an orphan designation application (RRadj 3.9, 95% CI 1.9-8.3) and confirmed that prevalence of the disease is also associated with filing an application for an orphan designation (RRadj 2.8, 95% CI 1.4-5.4). For only one out of four known exceptionally rare metabolic inherited diseases sponsors applied for an orphan designation at FDA or EMA. These applications were found to be associated with the prevalence of the rare disease and the level of available scientific knowledge on the proof of concept linking possible drug candidates to the disease of interest.

Bilateral Hearing Loss is Associated with Decreased Nonverbal Intelligence in US Children Ages 6 to 16 Years

PubMed Central

Emmett, Susan D.; Francis, Howard W.

2017-01-01

Objectives To evaluate the association between hearing loss and nonverbal intelligence in US children. Study Design The Third National Health and Nutrition Examination Survey (NHANES III) is a cross-sectional survey (1988–1994) that used complex multistage sampling design to produce nationally representative demographic and examination data. Methods A total of 4823 children ages 6–16 years completed audiometric evaluation and cognitive testing during NHANES III. Hearing loss was defined as low frequency pure tone average (PTA)>25 decibels (dB) (0.5,1,2 kHz) or high frequency PTA>25dB (3,4,6,8 kHz) and was designated as unilateral or bilateral. Nonverbal intelligence was measured using the Wechsler Intelligence Scale for Children-Revised block design subtest. Low nonverbal intelligence was defined as a standardized score <4, two standard deviations below the standardized mean of 10. Results Mean nonverbal intelligence scores differed between children with normal hearing (9.59) and children with bilateral (6.87; p=0.02) but not unilateral (9.12; p=0.42) hearing loss. Non-Hispanic black race/ethnicity and family income<$20,000 were associated with 3.92 and 1.67 times higher odds of low nonverbal intelligence, respectively (OR 3.92; p<0.001; OR 1.67; p=0.02). Bilateral hearing loss was independently associated with 5.77 times increased odds of low nonverbal intelligence compared to normal hearing children (OR 5.77; p=0.02). Unilateral hearing loss was not associated with higher odds of low nonverbal intelligence (OR 0.73; p=0.40). Conclusion Bilateral but not unilateral hearing loss is associated with decreased nonverbal intelligence in US children. Longitudinal studies are urgently needed to better understand these associations and their potential impact on future opportunities. PMID:24913183

Research on design connotation of hair drier system

NASA Astrophysics Data System (ADS)

Li, Yongchuan; Wu, Qiong

2018-04-01

After the analysis and summary of the research on the design of hair drier system, the system design is focused on. Product system design is not only to study its entity, but also is recognized as the part, element and component with a systematic feature to deeply analyze the innovation way of product system design, which is taken as its concept to carry out the association analysis on the component elements of hair driers and the overall analysis and study on the system design process of hair dryers. The product life cycle is taken as the main goal, through system analysis, system synthesis and system optimization, to solve the problems of product design. It is of great practical significance.

The Role of Exercise Self-Efficacy, Perceived Exertion, Event-Related Stress, and Demographic Factors in Predicting Physical Activity among College Freshmen

ERIC Educational Resources Information Center

Brannagan, Kim

2011-01-01

Objectives: The focus of this study was to examine the relationship among precursors to physical activity, including exercise self-efficacy, perceived exertion, stress, and demographic factors, among college students. Design: This study employed an associational design. Setting: The study population was college freshmen in southeast Louisiana who…

Friends Don't Let Friends Drive Drunk, But Do They Let Friends Drive High?

ERIC Educational Resources Information Center

Glascoff, Mary A.; Shrader, Joe S.; Haddock, Rose K.

2013-01-01

This study reports on a study of college students at a state supported university regarding the use of designated drivers associated with illicit drug use, especially marijuana use. The purpose of the study was to examine whether college students report that they drive under the influence of illicit drugs, if they use the strategy of designating a…

Contact lens-induced circumlimbal staining in silicone hydrogel contact lenses worn on a daily wear basis.

PubMed

Maïssa, Cécile; Guillon, Michel; Garofalo, Renee J

2012-01-01

The principal objective of the study was to measure the conjunctival staining produced in the circumlimbal region by silicone hydrogel contact lenses with different edge designs. The secondary objective was to investigate the association between circumlimbal staining and comfort. Four silicone hydrogel contact lenses: ACUVUE OASYS (knife edge design), AIR OPTIX, Biofinity (chisel edge rounded edge combination), and PureVision (rounded edge design), and 1 hydrogel contact lens, ACUVUE 2 (knife edge design), were tested. The study was conducted on a cohort population of 27 established soft contact lens wearers, who wore each contact lens type, in a random order, for a period of 10 (±2) days. Circumlimbal staining was measured in a double-masked fashion through image analysis of digital photographs of lissamine green taken under controlled experimental conditions. The results obtained showed that contact lens edge design was the primary factor controlling circumlimbal staining for silicone hydrogel lenses: a rounded edge away from the ocular surface produced the lowest staining (average, 0.19%) and a knife edge in close apposition to the ocular surface produced the highest staining (average, 1.34%). Contact lens material rigidity was also identified to affect circumlimbal staining and an inverse association between circumlimbal staining and contact lens comfort was demonstrated: the rounded edge design produced the lowest comfort (72 of 100) and the knife edge design produced the highest (87 out of 100). Soft contact lens wear induces circumlimbal staining, the level of staining being influenced by the contact lens edge design. However, high level of circumlimbal staining is not associated with decreased comfort.

Dual arm master controller development

NASA Technical Reports Server (NTRS)

Kuban, D. P.; Perkins, G. S.

1985-01-01

The advanced servomanipulator (ASM) slave was designed with an anthropomorphic stance gear/torque tube power drives, and modular construction. These features resulted in increased inertia, friction, and backlash relative to tape driven manipulators. Studies were performed which addressed to human factor design and performance tradeoffs associated with the corresponding master controller best suited for the ASM. The results of these studies, as well as the conceptual design of the dual arm master controller, are presented.

Musculoskeletal Problems in Iranian Hand-Woven Shoe-Sole Making Operation and Developing Guidelines for Workstation Design.

PubMed

Veisi, H; Choobineh, A R; Ghaem, H

2016-04-01

Musculoskeletal disorders (MSDs) are among important health problems in working population. Because of performing difficult physical activities, hand-woven shoe-sole makers are at risk of developing various types of MSDs. To determine the prevalence of musculoskeletal symptoms in different body areas of hand-woven shoe-sole makers, assess workers' postures and workstations, evaluate ergonomic and individual factors associated with MSDs, and develop guidelines for designing hand-woven shoe-sole making workstation. In this cross-sectional study, the prevalence of MSDs symptoms and their risk factors were studied among 240 hand-woven shoe-sole makers. Working posture and workstations were ergonomically assessed as well. The data were collected through interviewing and using Nordic musculoskeletal questionnaire and by direct observation of posture using RULA method. Logistic regression analysis was used to determine risk factors associated with MSDs symptoms. The prevalence and severity of MSDs symptoms were high among the study population. Ergonomic factors including daily working time, working posture, and force exertion, as well as individual factors, such as age, job tenure, and education were significantly associated with MSDs symptoms. It seems that the majority of ergonomics shortcomings originate from poorly designed workstation. Some general guidelines for designing shoe-sole making workstation are presented.

An alternative experimental case-control design for genetic association studies on bovine mastitis.

PubMed

Biffani, S; Del Corvo, M; Capoferri, R; Pedretti, A; Luini, M; Williams, J L; Pagnacco, G; Minvielle, F; Minozzi, G

2017-04-01

The possibility of using genetic control strategies to increase disease resistance to infectious diseases relies on the identification of markers to include in the breeding plans. Possible incomplete exposure of mastitis-free (control) animals, however, is a major issue to find relevant markers in genetic association studies for infectious diseases. Usually, designs based on elite dairy sires are used in association studies, but an epidemiological case-control strategy, based on cows repeatedly field-tested could be an alternative for disease traits. To test this hypothesis, genetic association results obtained in the present work from a cohort of Italian Holstein cows tested for mastitis over time were compared with those from a previous genome-wide scan on Italian Holstein sires genotyped with 50k single nucleotide polymorphisms for de-regressed estimated breeding values for somatic cell counts (SCCs) on Bos taurus autosome (BTA6) and BTA14. A total of 1121 cows were selected for the case-control approach (cases=550, controls=571), on a combination of herd level of SCC incidence and of within herd individual level of SCC. The association study was conducted on nine previously identified markers, six on BTA6 and four on BTA14, using the R statistical environment with the 'qtscore' function of the GenABEL package, on high/low adjusted linear score as a binomial trait. The results obtained in the cow cohort selected on epidemiological information were in agreement with those obtained from the previous sire genome-wide association study (GWAS). Six out of the nine markers showed significant association, four on BTA14 (rs109146371, rs109234250, rs109421300, rs109162116) and two on BTA6 (rs110527224 and rs42766480). Most importantly, using mastitis as a case study, the current work further validated the alternative use of historical field disease data in case-control designs for genetic analysis of infectious diseases in livestock.

Flux harmonics in large SFR cores in relation with core characteristics such as power peaks

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

Rimpault, G.; Buiron, L.; Fontaine, B.

2013-07-01

Designing future Sodium Fast Reactors (SFR) requires enhancing their operational performance and reducing the probability to go into core disruption. As a consequence of these constraints, these novel reactors exhibit rather unusual features compared to past designs. The cores are much larger with rather flat shape. The consequences of that shape on the core characteristics deserve to be studied. The approach taken in this paper is to calculate the eigenvalue associated to the first harmonic and its associated flux. It is demonstrated that these values are linked to some core features, in particular, those sensitive to spatial effects such asmore » power peaks induced by the movement of control rods. The uncertainty associated to these characteristics is being tentatively studied and guidelines for further studied are being identified. In the development strategy of these new SFR designs, a first demonstration plant of limited installed power (around 1500 MWth) will have to be built first. Identifying the possibility of going later to higher power plants (around 3600 MWth) without facing new challenges is an important criterion for designing such a plant. That strategy is being studied, in this paper, focusing on some rather frequent initiator such as the inadvertent control rod withdrawal for different core sizes with the help of the perturbation theory and the flux harmonics. (authors)« less

Vestibular Function Research (VFR) experiment. Phase B: Design definition study

NASA Technical Reports Server (NTRS)

1978-01-01

The Vestibular Functions Research (VFR) Experiment was established to investigate the neurosensory and related physiological processes believed to be associated with the space flight nausea syndrome and to develop logical means for its prediction, prevention and treatment. The VFR Project consists of ground and spaceflight experimentation using frogs as specimens. The phase B Preliminary Design Study provided for the preliminary design of the experiment hardware, preparation of performance and hardware specification and a Phase C/D development plan, establishment of STS (Space Transportation System) interfaces and mission operations, and the study of a variety of hardware, experiment and mission options. The study consist of three major tasks: (1) mission mode trade-off; (2) conceptual design; and (3) preliminary design.

De Novo Design and Experimental Characterization of Ultrashort Self-Associating Peptides

PubMed Central

Xue, Bo; Robinson, Robert C.; Hauser, Charlotte A. E.; Floudas, Christodoulos A.

2014-01-01

Self-association is a common phenomenon in biology and one that can have positive and negative impacts, from the construction of the architectural cytoskeleton of cells to the formation of fibrils in amyloid diseases. Understanding the nature and mechanisms of self-association is important for modulating these systems and in creating biologically-inspired materials. Here, we present a two-stage de novo peptide design framework that can generate novel self-associating peptide systems. The first stage uses a simulated multimeric template structure as input into the optimization-based Sequence Selection to generate low potential energy sequences. The second stage is a computational validation procedure that calculates Fold Specificity and/or Approximate Association Affinity (K*association) based on metrics that we have devised for multimeric systems. This framework was applied to the design of self-associating tripeptides using the known self-associating tripeptide, Ac-IVD, as a structural template. Six computationally predicted tripeptides (Ac-LVE, Ac-YYD, Ac-LLE, Ac-YLD, Ac-MYD, Ac-VIE) were chosen for experimental validation in order to illustrate the self-association outcomes predicted by the three metrics. Self-association and electron microscopy studies revealed that Ac-LLE formed bead-like microstructures, Ac-LVE and Ac-YYD formed fibrillar aggregates, Ac-VIE and Ac-MYD formed hydrogels, and Ac-YLD crystallized under ambient conditions. An X-ray crystallographic study was carried out on a single crystal of Ac-YLD, which revealed that each molecule adopts a β-strand conformation that stack together to form parallel β-sheets. As an additional validation of the approach, the hydrogel-forming sequences of Ac-MYD and Ac-VIE were shuffled. The shuffled sequences were computationally predicted to have lower K*association values and were experimentally verified to not form hydrogels. This illustrates the robustness of the framework in predicting self-associating tripeptides. We expect that this enhanced multimeric de novo peptide design framework will find future application in creating novel self-associating peptides based on unnatural amino acids, and inhibitor peptides of detrimental self-aggregating biological proteins. PMID:25010703

Factors Associated with Abnormal Eating Attitudes among Greek Adolescents

ERIC Educational Resources Information Center

Bilali, Aggeliki; Galanis, Petros; Velonakis, Emmanuel; Katostaras, Theofanis

2010-01-01

Objective: To estimate the prevalence of abnormal eating attitudes among Greek adolescents and identify possible risk factors associated with these attitudes. Design: Cross-sectional, school-based study. Setting: Six randomly selected schools in Patras, southern Greece. Participants: The study population consisted of 540 Greek students aged 13-18…

Toxoplasmosis gondii and schizophrenia: a case control study in a low Toxoplasma gondii seroprevalence Mexican population

USDA-ARS?s Scientific Manuscript database

There are conflicting reports concerning the association of T. gondii infection and schizophrenia. Therefore, we determined such association in a Mexican population of Mestizo ethnicity. Through a case-control study design, 50 schizophrenic patients and 150 control subjects matched by gender, age, r...

Reduced forced vital capacity in childhood associated with exposures to petroleum-related compounds at birth residence

EPA Science Inventory

Rationale: Previous studies have reported associations of ambient air pollutant exposures with childhood decrements in lung volumes. While the current study was designed primarily to examine traffic exposures, we also examined the impact of other early life exposures on pulmonary...

The role of genomics in the neonatal ICU.

PubMed

Maresso, Karen; Broeckel, Ulrich

2009-03-01

Results of both the Human Genome and International HapMap Projects have provided the technology and resources necessary to enable fundamental advances through the study of DNA sequence variation in almost all fields of medicine, including neonatology. Genome-wide association studies are now practical, and the first of these studies are appearing in the literature. This article provides the reader with an overview of the issues in technology and study design relating to genome-wide association studies and summarizes the current state of association studies in neonatal ICU populations with a brief review of the relevant literature. Future recommendations for genomic association studies in neonatal ICU populations are also provided.

ICU ward design and nosocomial infection rates: a cross-sectional study in Germany.

PubMed

Stiller, A; Schröder, C; Gropmann, A; Schwab, F; Behnke, M; Geffers, C; Sunder, W; Holzhausen, J; Gastmeier, P

2017-01-01

There is increasing interest in the effects of hospital and ward design on multi-faceted infection control. Definitive evidence is rare and the state of knowledge about current ward design is lacking. To collect data on the current status of ward design for intensive care units (ICUs) and to analyse associations between particular design factors and nosocomial infection rates. In 2015, operational infrastructure data were collected via an online questionnaire from ICUs participating voluntarily in the German nosocomial infection surveillance system (KISS). A multi-variate analysis was subsequently undertaken with nosocomial infection rates from the KISS database from 2014 to 2015. In total, 534 ICUs submitted data about their operational infrastructure. Of these, 27.1% of beds were hosted in single-bed rooms with a median size of 18m 2 (interquartile range 15-21m 2 ), and 73.5% of all ICU beds had a hand rub dispenser nearby. The authors were able to match 266 ICUs in the multi-variate analysis. ICUs with openable windows in patient rooms were associated with lower device-associated lower respiratory tract infections [odds ratio (OR) 0.73, 95% confidence interval (CI) 0.58-0.90]. ICUs with >40% two-bed rooms were associated with lower primary bloodstream infection rates (OR 0.66, 95% CI 0.51-0.86). Only minor associations were found between design factors and ICU infection rates. Most were surrogates for other risk factors. Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Association Between Barriers and Facilitators to Meeting the Dietary Guidelines for Americans and Body Weight Status: The HEALTH Study

USDA-ARS?s Scientific Manuscript database

Few Americans meet the Dietary Guidelines for Americans (DGA). Objective: The goal of this research was to examine the association between barriers and facilitators to meeting the DGA and weight in a multi-site study. Design: A cross-sectional study. Participants/Setting: A total of 836 caregiver-ch...

Models in the Design and Validation of Eddy Current Inspection for Cracking in the Shuttle Reaction Control System Thruster

NASA Technical Reports Server (NTRS)

Aldrin, John C.; Williams, Phillip A.; Wincheski, Russell (Buzz) A.

2008-01-01

A case study is presented for using models in eddy current NDE design for crack detection in Shuttle Reaction Control System thruster components. Numerical methods were used to address the complex geometry of the part and perform parametric studies of potential transducer designs. Simulations were found to show agreement with experimental results. Accurate representation of the coherent noise associated with the measurement and part geometry was found to be critical to properly evaluate the best probe designs.

13 CFR 120.850 - Expiration of Associate Development Company designation.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Development Company designation. 120.850 Section 120.850 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Development Company Loan Program (504) Associate Development Companies (adcs) § 120.850 Expiration of Associate Development Company designation. The designation of Associate Development...

Cornell Alliance for Science Evaluation of Consensus on Genetically Modified Food Safety: Weaknesses in Study Design

PubMed Central

Antoniou, Michael N.; Robinson, Claire J.

2017-01-01

Cornell Alliance for Science has launched an initiative in which “citizen scientists” are called upon to evaluate studies on health risks of genetically modified (GM) crops and foods. The purpose is to establish whether the consensus on GM food safety claimed by the American Association for the Advancement of Science (AAAS) is supported by a review of the scientific literature. The Alliance’s citizen scientists are examining more than 12,000 publication abstracts to quantify how far the scientific literature supports the AAAS’s statement. We identify a number of fundamental weaknesses in the Alliance’s study design, including evaluation is based only on information provided in the publication abstract; there is a lack of clarity as to what material is included in the 12,000 study abstracts to be reviewed, since the number of appropriately designed investigations addressing GM food safety are few; there is uncertainty as to whether studies of toxic effects arising from GM crop-associated pesticides will be included; there is a lack of clarity regarding whether divergent yet equally valid interpretations of the same study will be taken into account; and there is no definition of the cutoff point for consensus or non-consensus on GM food safety. In addition, vital industry proprietary biosafety data on GM crops and associated pesticides are not publicly available and is thus cannot inform this project. Based on these weaknesses in the study design, we believe it is questionable as to whether any objective or meaningful conclusion can be drawn from the Alliance’s initiative. PMID:28447029

Cornell Alliance for Science Evaluation of Consensus on Genetically Modified Food Safety: Weaknesses in Study Design.

PubMed

Antoniou, Michael N; Robinson, Claire J

2017-01-01

Cornell Alliance for Science has launched an initiative in which "citizen scientists" are called upon to evaluate studies on health risks of genetically modified (GM) crops and foods. The purpose is to establish whether the consensus on GM food safety claimed by the American Association for the Advancement of Science (AAAS) is supported by a review of the scientific literature. The Alliance's citizen scientists are examining more than 12,000 publication abstracts to quantify how far the scientific literature supports the AAAS's statement. We identify a number of fundamental weaknesses in the Alliance's study design, including evaluation is based only on information provided in the publication abstract; there is a lack of clarity as to what material is included in the 12,000 study abstracts to be reviewed, since the number of appropriately designed investigations addressing GM food safety are few; there is uncertainty as to whether studies of toxic effects arising from GM crop-associated pesticides will be included; there is a lack of clarity regarding whether divergent yet equally valid interpretations of the same study will be taken into account; and there is no definition of the cutoff point for consensus or non-consensus on GM food safety. In addition, vital industry proprietary biosafety data on GM crops and associated pesticides are not publicly available and is thus cannot inform this project. Based on these weaknesses in the study design, we believe it is questionable as to whether any objective or meaningful conclusion can be drawn from the Alliance's initiative.

Current Trends in Associate Degree Nursing Programs.

ERIC Educational Resources Information Center

Blackstone, Elaine Grant

This study was designed to ascertain current trends in associate degree nursing programs and to discover innovative ideas and techniques which could be applied to the existing program at Miami-Dade Community College (Florida). Data was compiled from interviews with representatives of ten associate degree nursing programs in six states. Information…

The Association between Learning Styles and Perception of Teaching Quality

ERIC Educational Resources Information Center

Jepsen, Denise M.; Varhegyi, Melinda M.; Teo, Stephen T. T.

2015-01-01

Purpose: Although learning styles and teaching quality have been studied separately, the association between the association between the two has yet to be identified. The purpose of this paper is to establish the relationship between students' learning styles with students' perceptions of teaching quality. Design/methodology/approach: The study…

The Energy Balance Study: The Design and Baseline Results for a Longitudinal Study of Energy Balance

ERIC Educational Resources Information Center

Hand, Gregory A.; Shook, Robin P.; Paluch, Amanda E.; Baruth, Meghan; Crowley, E. Patrick; Jaggers, Jason R.; Prasad, Vivek K.; Hurley, Thomas G.; Hebert, James R.; O'Connor, Daniel P.; Archer, Edward; Burgess, Stephanie; Blair, Steven N.

2013-01-01

Purpose: The Energy Balance Study (EBS) was a comprehensive study designed to determine over a period of 12 months the associations of caloric intake and energy expenditure on changes in body weight and composition in a population of healthy men and women. Method: EBS recruited men and women aged 21 to 35 years with a body mass index between 20…

Systematic review of descriptive studies that investigated associated factors with the management of incontinence in older people in care homes.

PubMed

Roe, Brenda; Flanagan, Lisa; Jack, Barbara; Shaw, Christine; Williams, Kate; Chung, Alan; Barrett, James

2013-03-01

Incontinence is prevalent among older populations and residents in care homes. This paper is a review of descriptive studies that investigated associated factors related to managing urinary incontinence in older people in care homes. A systematic literature review was undertaken. MEDLINE and CINHAL were searched from 1996-2010 using the Cochrane Incontinence Review Group search strings for urinary and faecal incontinence including all research designs. Sixteen studies were identified that reported on associated factors related to comorbidities, management preferences, policies, staff views and knowledge or methodological studies. Non-invasive methods involving toileting and use of pads were common management approaches. No studies aimed at maintaining continence were identified. Factors associated with incontinence need to also be considered when planning and managing care for individuals, and developing and designing systems of care within care homes. Further study in care home populations to change or inform practice and provide effective care is warranted. Preventive studies that maintain continence are required. Older people and their families should be involved with decisions regarding their preferred care, goals, management and outcomes for managing incontinence, promoting or maintaining continence. © 2011 Blackwell Publishing Ltd.

A Multi- and Cross-Disciplinary Capstone Experience in Engineering Art: Animatronic Polar Bear

ERIC Educational Resources Information Center

Sirinterlikci, Arif; Toukonen, Kayne; Mason, Steve; Madison, Russel

2005-01-01

An animatronic robot was designed and constructed for the 2003 Annual Student Robotic Technology and Engineering Challenge organized by the Robotics International (RI) association of the Society of Manufacturing Engineers (SME). It was also the senior capstone design project for two of the design team members. After a thorough study of body and…

iPad versus Traditional Tools in Art and Design: A Complementary Association

ERIC Educational Resources Information Center

Souleles, Nicos

2017-01-01

There is continuous debate on the role of digital media tools in art and design Higher Education, and in particular their potential contribution towards teaching and learning. The related literature indicates that there is a dichotomy between digital and traditional tools. This study investigates the views of a cohort of art and design students…

Cultural Resources Survey of the Morgan City and Vicinity Hurricane Protection Project.

DTIC Science & Technology

1985-12-30

22 5 RESEARCH DESIGN ...................................... 26 Introduction ..................................... 26 Theoretical... designed to enable the construction or enlargement of protective levees and drainage structures for both the Franklin and Morgan City areas, in St...the larger project area was conducted during May-July, 1985, by R. Christopher Goodwin and Associates, Inc. The research design for this study

Work-related stress as a cardiovascular risk factor in police officers: a systematic review of evidence.

PubMed

Magnavita, N; Capitanelli, I; Garbarino, S; Pira, E

2018-05-01

Several studies suggest that work-related stress in police officers may be associated with an increased risk of cardiovascular diseases. A systematic review of studies is, however, still lacking. According to PRISMA statement, a systematic search of PubMed, ISI Web of Science, Cinahl and PsychInfo electronic databases was undertaken. Studies published in English between 1/1/2000 and 31/12/2016 were included. A studies quality assessment was performed using the Newcastle Ottawa scale (NOS). The preliminary search retrieved 752 records. After selection, 16 studies (total population 17,698) were retrieved. The average quality of studies was low. Exposure to stress in cross-sectional studies was inconstantly associated with hypertension, obesity, dyslipidaemia, and impaired glucose metabolism. In addition, there was a prevalence of positive studies showing an association between stress and cardiovascular disease morbidity. Studies of higher quality, such as longitudinal studies on large sample size, were more supportive of a significant positive association between stress and cardiovascular risk factors. Results were, however, often conflicting and inconsistent with regard to definitions and measurement of stress, features of individual study design, study conduct, and conclusions drawn. A sound precautionary principle would be to adopt worksite health promotion programs designed to implement stress management strategies in this category of workers.

The Effects of Acute Cannabis Use on Nontraffic Injury Risk: Reviewing the Available Literature and Identifying Ways Forward

PubMed Central

Andreuccetti, Gabriel; Ye, Yu; Kang, Jaewook; Korcha, Rachael; Witbrodt, Jane A.; Carvalho, Heraclito B.; Cherpitel, Cheryl J.

2018-01-01

Recent evidence has indicated that cannabis use before driving is associated with a modest but increased risk for traffic-related injuries. However, the question of whether recent cannabis use is associated with a greater risk for other types of injuries remains unanswered. Aiming to understand better how acute cannabis use might affect the risk for all causes of injury, we have summarized the limited data available in the literature on the risk of non-traffic injuries associated with recent cannabis use. Very few studies were able to provide estimate risks for all injuries or injuries other than those related to road traffic injuries, with the limited evidence available showing mixed findings. The only significant risk found (in only one study) suggests an inverse association between all injuries and cannabis use. Study designs are limited, and the majority of studies have neither data on acute cannabis use among injured individuals nor a valid control group for estimating injury risk attributable to cannabis. In conclusion, studies of the association between cannabis and non-traffic injuries present several limitations, particularly regarding sampling strategies, injury risk assessment for different causes of injury, and a dose-response risk relationship with injury. Further studies, incorporating better design for different causes of injury and drug testing, are required to reach firmer conclusions on the association between cannabis use and non-traffic injury risk. PMID:29456273

Job design, employment practices and well-being: a systematic review of intervention studies.

PubMed

Daniels, Kevin; Gedikli, Cigdem; Watson, David; Semkina, Antonina; Vaughn, Oluwafunmilayo

2017-09-01

There is inconsistent evidence that deliberate attempts to improve job design realise improvements in well-being. We investigated the role of other employment practices, either as instruments for job redesign or as instruments that augment job redesign. Our primary outcome was well-being. Where studies also assessed performance, we considered performance as an outcome. We reviewed 33 intervention studies. We found that well-being and performance may be improved by: training workers to improve their own jobs; training coupled with job redesign; and system wide approaches that simultaneously enhance job design and a range of other employment practices. We found insufficient evidence to make any firm conclusions concerning the effects of training managers in job redesign and that participatory approaches to improving job design have mixed effects. Successful implementation of interventions was associated with worker involvement and engagement with interventions, managerial commitment to interventions and integration of interventions with other organisational systems. Practitioner Summary: Improvements in well-being and performance may be associated with system-wide approaches that simultaneously enhance job design, introduce a range of other employment practices and focus on worker welfare. Training may have a role in initiating job redesign or augmenting the effects of job design on well-being.

Public Interest in Medical Research Participation: Does It Matter if Patients or Community Members Have Helped Design the Study?

PubMed

Cobb, Enesha M; Gebremariam, Achamyeleh; Singer, Dianne; Davis, Matthew M

2015-10-01

We determined national levels of public participation in medical research study design. We compared public interest in medical research participation (MRP) in studies overall, versus studies explicitly designed with public involvement. Cross-sectional household survey of US population in June 2013. Descriptive statistics estimated participation in medical research study design. Chi-square test compared levels of interest in MRP if respondent knew patients or community members helped design the study. Of 2,048 respondents (participation rate 60%), 5% knew someone who had helped design a medical research study. There was no association between having known someone or personal participation in study design and willingness to engage in MRP. Although the overall proportion of respondents who would consider MRP initially (51%) was similar to the proportion who would consider MRP with community member involvement in study design (49%), the changes in respondents' views across the different scenarios were significantly greater than what would have been expected by chance. We found similar levels of interest in MRP whether or not the public is involved in medical research study design. This finding may indicate that public involvement in study design, like community-based participatory research, may not affect overall rates of MRP. © 2015 Wiley Periodicals, Inc.

Stroke-Related Knowledge, Lifestyle Behaviours and Health Beliefs in Singaporean Chinese: Implications for Health Education

ERIC Educational Resources Information Center

Wong, Wai Pong; Yeung, Meredith; Loh, Susan; Lee, Mina; Ghazali, F.; Chan, C. J.; Feng, S.; Liew, Y. V.; Seah, P. F.; Wee, J.; Wang, J.; Huang, X.; Dean, Elizabeth

2013-01-01

Objective: The objective of the present study was to describe stroke-related knowledge (risk factors, warning signs and emergency response), lifestyle behaviours and health beliefs among Singaporean Chinese, and to identify any factors associated with such knowledge, behaviours and beliefs. Design: This was a cross-sectional study design employing…

Fusion reactor blanket/shield design study

NASA Astrophysics Data System (ADS)

Smith, D. L.; Clemmer, R. G.; Harkness, S. D.; Jung, J.; Krazinski, J. L.; Mattas, R. F.; Stevens, H. C.; Youngdahl, C. K.; Trachsel, C.; Bowers, D.

1979-07-01

A joint study of Tokamak reactor first wall/blanket/shield technology was conducted to identify key technological limitations for various tritium breeding blanket design concepts, establishment of a basis for assessment and comparison of the design features of each concept, and development of optimized blanket designs. The approach used involved a review of previously proposed blanket designs, analysis of critical technological problems and design features associated with each of the blanket concepts, and a detailed evaluation of the most tractable design concepts. Tritium breeding blanket concepts were evaluated according to the proposed coolant. The effort concentrated on evaluation of lithium and water cooled blanket designs and helium and molten salt cooled designs. Generalized nuclear analysis of the tritium breeding performance, an analysis of tritium breeding requirements, and a first wall stress analysis were conducted as part of the study. The impact of coolant selection on the mechanical design of a Tokamak reactor was evaluated. Reference blanket designs utilizing the four candidate coolants are presented.

A tool for selecting SNPs for association studies based on observed linkage disequilibrium patterns.

PubMed

De La Vega, Francisco M; Isaac, Hadar I; Scafe, Charles R

2006-01-01

The design of genetic association studies using single-nucleotide polymorphisms (SNPs) requires the selection of subsets of the variants providing high statistical power at a reasonable cost. SNPs must be selected to maximize the probability that a causative mutation is in linkage disequilibrium (LD) with at least one marker genotyped in the study. The HapMap project performed a genome-wide survey of genetic variation with about a million SNPs typed in four populations, providing a rich resource to inform the design of association studies. A number of strategies have been proposed for the selection of SNPs based on observed LD, including construction of metric LD maps and the selection of haplotype tagging SNPs. Power calculations are important at the study design stage to ensure successful results. Integrating these methods and annotations can be challenging: the algorithms required to implement these methods are complex to deploy, and all the necessary data and annotations are deposited in disparate databases. Here, we present the SNPbrowser Software, a freely available tool to assist in the LD-based selection of markers for association studies. This stand-alone application provides fast query capabilities and swift visualization of SNPs, gene annotations, power, haplotype blocks, and LD map coordinates. Wizards implement several common SNP selection workflows including the selection of optimal subsets of SNPs (e.g. tagging SNPs). Selected SNPs are screened for their conversion potential to either TaqMan SNP Genotyping Assays or the SNPlex Genotyping System, two commercially available genotyping platforms, expediting the set-up of genetic studies with an increased probability of success.

A Time Series Study of Factors Associated with Retention and Attrition of Older Adult Child-Care Workers. Final Report.

ERIC Educational Resources Information Center

Newman, Sally; Engel, Rafael; Ward, Christopher; Karip, Emin; Faux, Robert

The work-related and personal factors associated with the willingness and ability of older adults to remain as child care workers and the factors associated with leaving child care work were studied in a time-series design. Subjects were 534 persons aged 50 years and older who were working for pay as child care providers. Of these, 341 replied to…

Self-esteem and self-efficacy as predictors of attrition in associate degree nursing students.

PubMed

Peterson-Graziose, Virginia; Bryer, Jennifer; Nikolaidou, Maria

2013-06-01

There is a serious and growing shortage of nurses in the United States, and the high rate of student attrition from nursing programs has further added to this problem. The challenge for schools of nursing is to recruit increased numbers of qualified candidates into their programs and to determine ways to decrease the rate of student attrition. The purpose of this study was to determine whether self-esteem, self-efficacy, and life stressors were significantly related to student attrition in first-semester associate degree nursing students. A descriptive correlational design and nonprobability convenience sample of first-semester associate degree nursing students was used. Data were gathered using the Rosenberg Self-Esteem Scale, the General Self-Efficacy Scale, and the Holmes and Rahe Social Readjustment Rating Scale. Findings indicated that self-esteem was significantly associated with student attrition. Results from this study provide the basis for targeted interventions designed to decrease student attrition rates in associate degree nursing programs. Copyright 2013, SLACK Incorporated.

Psychosocial adjustment and mental health in former child soldiers--systematic review of the literature and recommendations for future research.

PubMed

Betancourt, Theresa S; Borisova, Ivelina; Williams, Timothy P; Meyers-Ohki, Sarah E; Rubin-Smith, Julia E; Annan, Jeannie; Kohrt, Brandon A

2013-01-01

This article reviews the available quantitative research on psychosocial adjustment and mental health among children (age <18 years) associated with armed forces and armed groups (CAAFAG)--commonly referred to as child soldiers. PRISMA standards for systematic reviews were used to search PubMed, PsycInfo, JSTOR, and Sociological Abstracts in February 2012 for all articles on former child soldiers and CAAFAG. Twenty-one quantitative studies from 10 countries were analyzed for author, year of publication, journal, objectives, design, selection population, setting, instruments, prevalence estimates, and associations with war experiences. Opinion pieces, editorials, and qualitative studies were deemed beyond the scope of this study. Quality of evidence was rated according to the systematic assessment of quality in observational research (SAQOR). According to SAQOR criteria, among the available published studies, eight studies were of high quality, four were of moderate quality, and the remaining nine were of low quality. Common limitations were lack of validated mental health measures, unclear methodology including undefined sampling approaches, and failure to report missing data. Only five studies included a comparison group of youth not involved with armed forces/armed groups, and only five studies assessed mental health at more than one point in time. Across studies, a number of risk and protective factors were associated with postconflict psychosocial adjustment and social reintegration in CAAFAG. Abduction, age of conscription, exposure to violence, gender, and community stigma were associated with increased internalizing and externalizing mental health problems. Family acceptance, social support, and educational/economic opportunities were associated with improved psychosocial adjustment. Research on the social reintegration and psychosocial adjustment of former child soldiers is nascent. A number of gaps in the available literature warrant future study. Recommendations to bolster the evidence base on psychosocial adjustment in former child soldiers and other war-affected youth include more studies comprising longitudinal study designs, and validated cross-cultural instruments for assessing mental health, as well as more integrated community-based approaches to study design and research monitoring. © 2012 The Authors. Journal of Child Psychology and Psychiatry © 2012 Association for Child and Adolescent Mental Health.

Association between circulating irisin and insulin resistance in non-diabetic adults: A meta-analysis.

PubMed

Qiu, Shanhu; Cai, Xue; Yin, Han; Zügel, Martina; Sun, Zilin; Steinacker, Jürgen Michael; Schumann, Uwe

2016-06-01

Exogenous administration of recombinant irisin improves glucose metabolism. However, the association of endogenous circulating (plasma/serum) irisin with insulin resistance remains poorly delineated. This study was aimed to examine this association by meta-analyzing the current evidence without study design restriction in non-diabetic adults. Peer-reviewed studies written in English from 3 databases were searched to December 2015. Studies that reported the association between circulating irisin and insulin resistance (or its reverse, insulin sensitivity) in non-diabetic non-pregnant adults (mean ages ≥18years) were included. The pooled correlation coefficient (r) and 95% confidence intervals (CIs) were calculated using a random-effects model. Subgroup analyses and meta-regression were performed to explore potential sources of heterogeneity. Of the 195 identified publications, 17 studies from 15 articles enrolling 1912 participants reported the association between circulating irisin and insulin resistance. The pooled effect size was 0.15 (95% CI: 0.07 to 0.22) with a substantial heterogeneity (I(2)=55.5%). This association seemed to be modified by glycemic status (fasting blood glucose ≥6.1mmol/L versus <6.1mmol/L) and racial-ethnic difference (Asians versus Europeans versus Americans), but not by sex difference, sampling time-point, blood sample type, ELISA kits used, baseline age, or body mass index. Circulating irisin was inversely associated with insulin sensitivity (6 studies; r=-0.17, 95% CI: -0.25 to -0.09). Circulating irisin is directly and positively associated with insulin resistance in non-diabetic adults. However, this association is rather small and requires further clarification, in particular by well-designed large epidemiological studies with overall, race-, and sex-specific analyses. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

The success of pharmacogenomics in moving genetic association studies from bench to bedside: study design and implementation of precision medicine in the post-GWAS era.

PubMed

Ritchie, Marylyn D

2012-10-01

Pharmacogenomics is emerging as a popular type of study for human genetics in recent years. This is primarily due to the many success stories and high potential for translation to clinical practice. In this review, the strengths and limitations of pharmacogenomics are discussed as well as the primary epidemiologic, clinical trial, and in vitro study designs implemented. A brief discussion of molecular and analytic approaches will be reviewed. Finally, several examples of bench-to-bedside clinical implementations of pharmacogenetic traits will be described. Pharmacogenomics continues to grow in popularity because of the important genetic associations identified that drive the possibility of precision medicine.

Non-psychotropic medication and risk of suicide or attempted suicide: a systematic review

PubMed Central

Gorton, Hayley C; Webb, Roger T; Kapur, Navneet; Ashcroft, Darren M

2016-01-01

Objectives To establish which non-psychotropic medications have been assessed in relation to risk of suicide or attempted suicide in observational studies, document reported associations and consider study strengths and limitations. Design Systematic review. Methods Four databases (Embase, Medline, PsycINFO and International Pharmaceutical Abstracts) were searched from 1990 to June 2014, and reference lists of included articles were hand-searched. Case–control, cohort and case only studies which reported suicide or attempted suicide in association with any non-psychotropic medication were included. Outcome measures The outcomes eligible for inclusion were suicide and attempted suicide, as defined by the authors of the included study. Results Of 11 792 retrieved articles, 19 were eligible for inclusion. Five studies considered cardiovascular medication and antiepileptics; two considered leukotriene receptor antagonists, isotretinoin and corticosteroids; one assessed antibiotics and another assessed varenicline. An additional study compared multiple medications prescribed to suicide cases versus controls. There was marked heterogeneity in study design, outcome and exposure classification, and control for confounding factors; particularly comorbid mental and physical illness. No increased risk was associated with cardiovascular medications, but associations with other medications remained inconclusive and meta-analysis was inappropriate due to study heterogeneity. Conclusions Whether non-psychotropic medications are associated with increased risk of suicide or attempted suicide remains largely unknown. Robust identification of suicide outcomes and control of comorbidities could improve quantification of risk associated with non-psychotropic medication, beyond that conferred by underlying physical and mental illnesses. PMID:26769782

Selenium intake and metabolic syndrome: A systematic review.

PubMed

Retondario, Anabelle; Fernandes, Ricardo; Rockenbach, Gabriele; Alves, Mariane de Almeida; Bricarello, Liliana Paula; Trindade, Erasmo Benicio Santos de Moraes; Vasconcelos, Francisco de Assis Guedes de

2018-03-02

Metabolic syndrome is a multi-causal disease. Its treatment includes lifestyle changes with a focus on weight loss. This systematic review assessed the association between Selenium intake and metabolic syndrome. Data were collected mainly from four databases: PubMed, CENTRAL (Cochrane), Scopus and Web of Knowledge. Keywords related to metabolic syndrome, selenium, as well as metabolic syndrome features were searched. This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement. A systematic review protocol was registered at PROSPERO (n. 42016046321). Two reviewers independently screened 2957 abstracts. Six studies were included to perform data extraction with standardized spreadsheets. The risk of bias was assessed by using specific tools according to the design of the relevant studies. An assessment was carried out based on the appropriateness of the study reports accordingly to STROBE and the CONSORT-based checklist for each study design. Three studies found no association between Selenium intake and metabolic syndrome; two of them found an inverse association; and one study found a direct association between Selenium intake and metabolic syndrome. One study also showed an inverse association between Selenium intake and the prevalence of high waist circumference, high diastolic blood pressure, and hyperglycaemia in women. Overall, based on the argumentation and results of this study, it is possible to conclude that Selenium intake and metabolic syndrome are not clearly associated in adults and elderly. Copyright © 2018 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Identifying crash contributory factors at urban roundabouts and using association rules to explore their relationships to different crash types.

PubMed

Montella, Alfonso

2011-07-01

The use of roundabouts improves intersection safety by eliminating or altering conflict types, reducing crash severity, and causing drivers to reduce speeds. However, roundabout performances can degrade if precautions are not taken during either the design or the operation phase. Therefore, additional information on the safety of the roundabouts is extremely helpful for planners and designers in identifying existing deficiencies and in refining the design criteria currently being used. The aim of the paper was to investigate the crash contributory factors in 15 urban roundabouts located in Italy and to study the interdependences between these factors. The crash data refer to the period 2003-2008. The identification of the crash contributory factors was based on site inspections and rigorous analyses performed by a team of specialists with a relevant road safety engineering background. Each roundabout was inspected once every year from 2004 to 2009, both in daytime and in nighttime. Overall, 62 different contributory factors and 2156 total contributory factors were identified. In 51 crashes, a single contributory factor was found, whereas in the other 223 crashes, a combination of contributory factors was identified. Given the large amount of data, the interdependences between the contributory factors and between the contributory factors and the different crash types were explored by an association discovery. Association discovery is the identification of sets of items (i.e., crash contributory factors and crash types in our study) that occur together in a given event (i.e., a crash in our study). The rules were filtered by support, confidence, and lift. As a result, 112 association rules were discovered. Overall, numerous contributory factors related to the road and environment deficiencies but not related to the road user or to the vehicle were identified. The most important factors related to geometric design were the radius of deflection and the deviation angle. In existing roundabouts, the improvement of these factors might be quite expensive, but the crucial role of a moderate radius of deflection and a large deviation angle in the design of new roundabouts was stressed. Many of the contributory factors were related to markings and signs, and these factors could be easily removed with low-cost safety measures. Furthermore, because of the association between the markings, signs, and geometric design contributory factors, the study results suggest that the improvement in markings and signs might also have a significant effect in the sites where geometric design deficiencies were identified as contributory factors. Copyright © 2011 Elsevier Ltd. All rights reserved.

Preservice Teachers' Critical Thinking Dispositions and Web 2.0 Competencies

ERIC Educational Resources Information Center

Sendag, Serkan; Erol, Osman; Sezgin, Sezan; Dulkadir, Nihal

2015-01-01

The aim of this study was to investigate the associations between preservice teachers' Web 2.0 competencies and their critical thinking disposition (CTD). The study employed an associational research design using California Critical Thinking Disposition-Inventory (CCTD-I) and a Web 2.0 competency questionnaire including items related to Web 2.0…

Risk Factors Associated with Obesity in Children of Different Racial Backgrounds

ERIC Educational Resources Information Center

Urrutia-Rojas, Ximena; Ahmad, Naveed; Bayona, Manuel; Bae, Sejong; Rivers, Patrick A; Singh, Karan P

2008-01-01

Objective: The purpose of this study is to determine specific risk factors associated with obesity among African American, Hispanic and Caucasian children. Design: This is a cross-sectional study conducted on 1076 fifth grade children from 17 elementary schools at Fort Worth, Texas. Data were collected through questionnaires and physical…

Factors Associated with Transfer of Training in Workplace E-Learning

ERIC Educational Resources Information Center

Park, Ji-Hye; Wentling, Tim

2007-01-01

Purpose--The purpose of this study is to investigate the effect of factors associated with e-learning, particularly computer attitudes and usability, on transfer of training in workplace e-learning courses. Design/methodology/approach--This study relied on quantitative data obtained from four online survey questionnaires. The sample of this study…

Factors Associated with Job Content Plateauing among Older Workers

ERIC Educational Resources Information Center

Armstrong-Stassen, Marjorie

2008-01-01

Purpose: The purpose of this paper is to identify personal and work environment factors associated with the experience of job content plateauing among older workers. Design/methodology/approach: Two cross-sectional studies, each including two samples, were conducted. In each study, one sample consisted of a diverse group of older workers and the…

Marginal Structural Models for Case-Cohort Study Designs to Estimate the Association of Antiretroviral Therapy Initiation With Incident AIDS or Death

PubMed Central

Cole, Stephen R.; Hudgens, Michael G.; Tien, Phyllis C.; Anastos, Kathryn; Kingsley, Lawrence; Chmiel, Joan S.; Jacobson, Lisa P.

2012-01-01

To estimate the association of antiretroviral therapy initiation with incident acquired immunodeficiency syndrome (AIDS) or death while accounting for time-varying confounding in a cost-efficient manner, the authors combined a case-cohort study design with inverse probability-weighted estimation of a marginal structural Cox proportional hazards model. A total of 950 adults who were positive for human immunodeficiency virus type 1 were followed in 2 US cohort studies between 1995 and 2007. In the full cohort, 211 AIDS cases or deaths occurred during 4,456 person-years. In an illustrative 20% random subcohort of 190 participants, 41 AIDS cases or deaths occurred during 861 person-years. Accounting for measured confounders and determinants of dropout by inverse probability weighting, the full cohort hazard ratio was 0.41 (95% confidence interval: 0.26, 0.65) and the case-cohort hazard ratio was 0.47 (95% confidence interval: 0.26, 0.83). Standard multivariable-adjusted hazard ratios were closer to the null, regardless of study design. The precision lost with the case-cohort design was modest given the cost savings. Results from Monte Carlo simulations demonstrated that the proposed approach yields approximately unbiased estimates of the hazard ratio with appropriate confidence interval coverage. Marginal structural model analysis of case-cohort study designs provides a cost-efficient design coupled with an accurate analytic method for research settings in which there is time-varying confounding. PMID:22302074

mHealth in Urology: A Review of Experts' Involvement in App Development.

PubMed

Pereira-Azevedo, Nuno; Carrasquinho, Eduardo; Cardoso de Oliveira, Eduardo; Cavadas, Vitor; Osório, Luís; Fraga, Avelino; Castelo-Branco, Miguel; Roobol, Monique J

2015-01-01

Smartphones are increasingly playing a role in healthcare and previous studies assessing medical applications (apps) have raised concerns about lack of expert involvement and low content accuracy. However, there are no such studies in Urology. We reviewed Urology apps with the aim of assessing the level of participation of healthcare professionals (HCP) and scientific Urology associations in their development. A systematic search was performed on PubMed, Apple's App Store and Google's Play Store, for Urology apps, available in English. Apps were reviewed by three graders to determine the app's platform, target customer, developer, app type, app category, price and the participation of a HCP or a scientific Urology association in the development. The search yielded 372 apps, of which 150 were specific for Urology. A fifth of all apps had no HCP involvement (20.7%) and only a third had been developed with a scientific Urology association (34.7%). The lowest percentage of HCP (13.4%) and urological association (1.9%) involvement was in apps designed for the general population. Furthermore, there was no contribution from an Urology society in "Electronic Medical Record" nor in "Patient Information" apps. A limitation of the study is that only Android and iOS apps were reviewed. Despite the increasing Mobile Health (mHealth) market, this is the first study that demonstrates the lack of expert participation in the design of Urology apps, particularly in apps designed for the general public. Until clear regulation is enforced, the urological community should help regulate app development. Maintaining a register of certified apps or issuing an official scientific seal of approval could improve overall app quality. We propose that urologists become stakeholders in mHealth, shaping future app design and promoting peer-review app validation.

mHealth in Urology: A Review of Experts’ Involvement in App Development

PubMed Central

Pereira-Azevedo, Nuno; Carrasquinho, Eduardo; Cardoso de Oliveira, Eduardo; Cavadas, Vitor; Osório, Luís; Fraga, Avelino; Castelo-Branco, Miguel; Roobol, Monique J.

2015-01-01

Introduction Smartphones are increasingly playing a role in healthcare and previous studies assessing medical applications (apps) have raised concerns about lack of expert involvement and low content accuracy. However, there are no such studies in Urology. We reviewed Urology apps with the aim of assessing the level of participation of healthcare professionals (HCP) and scientific Urology associations in their development. Material and Methods A systematic search was performed on PubMed, Apple's App Store and Google's Play Store, for Urology apps, available in English. Apps were reviewed by three graders to determine the app’s platform, target customer, developer, app type, app category, price and the participation of a HCP or a scientific Urology association in the development. Results The search yielded 372 apps, of which 150 were specific for Urology. A fifth of all apps had no HCP involvement (20.7%) and only a third had been developed with a scientific Urology association (34.7%). The lowest percentage of HCP (13.4%) and urological association (1.9%) involvement was in apps designed for the general population. Furthermore, there was no contribution from an Urology society in "Electronic Medical Record" nor in "Patient Information" apps. A limitation of the study is that only Android and iOS apps were reviewed. Conclusions Despite the increasing Mobile Health (mHealth) market, this is the first study that demonstrates the lack of expert participation in the design of Urology apps, particularly in apps designed for the general public. Until clear regulation is enforced, the urological community should help regulate app development. Maintaining a register of certified apps or issuing an official scientific seal of approval could improve overall app quality. We propose that urologists become stakeholders in mHealth, shaping future app design and promoting peer-review app validation. PMID:25984916

Analysis of case-parent trios at a locus with a deletion allele: association of GSTM1 with autism.

PubMed

Buyske, Steven; Williams, Tanishia A; Mars, Audrey E; Stenroos, Edward S; Ming, Sue X; Wang, Rong; Sreenath, Madhura; Factura, Marivic F; Reddy, Chitra; Lambert, George H; Johnson, William G

2006-02-10

Certain loci on the human genome, such as glutathione S-transferase M1 (GSTM1), do not permit heterozygotes to be reliably determined by commonly used methods. Association of such a locus with a disease is therefore generally tested with a case-control design. When subjects have already been ascertained in a case-parent design however, the question arises as to whether the data can still be used to test disease association at such a locus. A likelihood ratio test was constructed that can be used with a case-parents design but has somewhat less power than a Pearson's chi-squared test that uses a case-control design. The test is illustrated on a novel dataset showing a genotype relative risk near 2 for the homozygous GSTM1 deletion genotype and autism. Although the case-control design will remain the mainstay for a locus with a deletion, the likelihood ratio test will be useful for such a locus analyzed as part of a larger case-parent study design. The likelihood ratio test has the advantage that it can incorporate complete and incomplete case-parent trios as well as independent cases and controls. Both analyses support (p = 0.046 for the proposed test, p = 0.028 for the case-control analysis) an association of the homozygous GSTM1 deletion genotype with autism.

Analysis of case-parent trios at a locus with a deletion allele: association of GSTM1 with autism

PubMed Central

Buyske, Steven; Williams, Tanishia A; Mars, Audrey E; Stenroos, Edward S; Ming, Sue X; Wang, Rong; Sreenath, Madhura; Factura, Marivic F; Reddy, Chitra; Lambert, George H; Johnson, William G

2006-01-01

Background Certain loci on the human genome, such as glutathione S-transferase M1 (GSTM1), do not permit heterozygotes to be reliably determined by commonly used methods. Association of such a locus with a disease is therefore generally tested with a case-control design. When subjects have already been ascertained in a case-parent design however, the question arises as to whether the data can still be used to test disease association at such a locus. Results A likelihood ratio test was constructed that can be used with a case-parents design but has somewhat less power than a Pearson's chi-squared test that uses a case-control design. The test is illustrated on a novel dataset showing a genotype relative risk near 2 for the homozygous GSTM1 deletion genotype and autism. Conclusion Although the case-control design will remain the mainstay for a locus with a deletion, the likelihood ratio test will be useful for such a locus analyzed as part of a larger case-parent study design. The likelihood ratio test has the advantage that it can incorporate complete and incomplete case-parent trios as well as independent cases and controls. Both analyses support (p = 0.046 for the proposed test, p = 0.028 for the case-control analysis) an association of the homozygous GSTM1 deletion genotype with autism. PMID:16472391

Methodological survey of designed uneven randomization trials (DU-RANDOM): a protocol.

PubMed

Wu, Darong; Akl, Elie A; Guyatt, Gordon H; Devereaux, Philip J; Brignardello-Petersen, Romina; Prediger, Barbara; Patel, Krupesh; Patel, Namrata; Lu, Taoying; Zhang, Yuan; Falavigna, Maicon; Santesso, Nancy; Mustafa, Reem A; Zhou, Qi; Briel, Matthias; Schünemann, Holger J

2014-01-23

Although even randomization (that is, approximately 1:1 randomization ratio in study arms) provides the greatest statistical power, designed uneven randomization (DUR), (for example, 1:2 or 1:3) is used to increase participation rates. Until now, no convincing data exists addressing the impact of DUR on participation rates in trials. The objective of this study is to evaluate the epidemiology and to explore factors associated with DUR. We will search for reports of RCTs published within two years in 25 general medical journals with the highest impact factor according to the Journal Citation Report (JCR)-2010. Teams of two reviewers will determine eligibility and extract relevant information from eligible RCTs in duplicate and using standardized forms. We will report the prevalence of DUR trials, the reported reasons for using DUR, and perform a linear regression analysis to estimate the association between the randomization ratio and the associated factors, including participation rate, type of informed consent, clinical area, and so on. A clearer understanding of RCTs with DUR and its association with factors in trials, for example, participation rate, can optimize trial design and may have important implications for both researchers and users of the medical literature.

Systematic Review of the Literature on Pain in Patients with Polytrauma Including Traumatic Brain Injury

PubMed Central

Dobscha, Steven K.; Clark, Michael E.; Morasco, Benjamin J.; Freeman, Michele; Campbell, Rose; Helfand, Mark

2010-01-01

Objective To review the literature addressing the assessment and management of pain in patients with polytraumatic injuries including traumatic brain injury (TBI) and blast-related headache, and to identify patient, clinician and systems factors associated with pain-related outcomes. Design Systematic review. Methods We conducted searches in MEDLINE of literature published from 1950 through July 2008. Due to a limited number of studies using controls or comparators, we included observational and rigorous qualitative studies. We systematically rated the quality of systematic reviews, cohort, and case-control design studies. Results One systematic review, 93 observational studies, and one qualitative research study met inclusion criteria. The literature search yielded no published studies that assessed measures of pain intensity or pain-related functional interference among patients with cognitive deficits due to TBI, that compared patients with blast-related headache with patients with other types of headache, or that assessed treatments for blast-related headache pain. Studies on the association between TBI severity and pain reported mixed findings. There was limited evidence that the following factors are associated with pain among TBI patients: severity, location, and multiplicity of injuries; insomnia; fatigue; depression; and post-traumatic stress disorder. Conclusions Very little evidence is currently available to guide pain assessment and treatment approaches in patients with polytrauma. Further research employing systematic observational as well as controlled intervention designs is clearly indicated. PMID:19818031

Energy in Our Society.

ERIC Educational Resources Information Center

Philadelphia Electric Co., PA. Energy Education Advisory Council.

This publication is a series of 13 original classroom instructional packets and an additional 4 units adapted from National Science Teachers Association units. Each packet is designed to supplement specific existing subject curricula. Units have been designed for physics, chemistry, English, mathematics, general science and studies. Packets…

A study of a space communication system for the control and monitoring of the electric distribution system. Volume 1: Summary

NASA Technical Reports Server (NTRS)

Vaisnys, A.

1980-01-01

It is technically feasible to design a satellite communication system to serve the United States electric utility industry's needs relative to load management, real-time operations management, remote meter reading, and to determine the costs of various elements of the system. A definition of distribution control and monitoring functions is given. Associated communications traffic is quantified. A baseline conceptual design in terms of operating capability and equipment is described, important factors to be considered in designing a system are examined, and preliminary cost data are provided. Factors associated with implementation are discussed and conclusions and recommendations are listed.

Biological and rearing mother influences on child ADHD symptoms: revisiting the developmental interface between nature and nurture.

PubMed

Harold, Gordon T; Leve, Leslie D; Barrett, Douglas; Elam, Kit; Neiderhiser, Jenae M; Natsuaki, Misaki N; Shaw, Daniel S; Reiss, David; Thapar, Anita

2013-10-01

Families of children with attention deficit hyperactivity disorder (ADHD) report more negative family relationships than families of children without ADHD. Questions remain as to the role of genetic factors underlying associations between family relationships and children's ADHD symptoms, and the role of children's ADHD symptoms as an evocative influence on the quality of relationships experienced within such families. Utilizing the attributes of two genetically sensitive research designs, the present study examined associations between biologically related and nonbiologically related maternal ADHD symptoms, parenting practices, child impulsivity/activation, and child ADHD symptoms. The combined attributes of the study designs permit assessment of associations while controlling for passive genotype-environment correlation and directly examining evocative genotype-environment correlation (rGE); two relatively under examined confounds of past research in this area. A cross-sectional adoption-at-conception design (Cardiff IVF Study; C-IVF) and a longitudinal adoption-at-birth design (Early Growth and Development Study; EGDS) were used. The C-IVF sample included 160 mothers and children (age 5-8 years). The EGDS sample included 320 linked sets of adopted children (age 6 years), adoptive-, and biologically related mothers. Questionnaires were used to assess maternal ADHD symptoms, parenting practices, child impulsivity/activation, and child ADHD symptoms. A cross-rater approach was used across measures of maternal behavior (mother reports) and child ADHD symptoms (father reports). Significant associations were revealed between rearing mother ADHD symptoms, hostile parenting behavior, and child ADHD symptoms in both samples. Because both samples consisted of genetically unrelated mothers and children, passive rGE was removed as a possible explanatory factor underlying these associations. Further, path analysis revealed evidence for evocative rGE processes in the longitudinal adoption-at-birth study (EGDS) from biologically related maternal ADHD symptoms to biologically unrelated maternal hostile parenting through early disrupted child behavior (impulsivity/activation), with maternal hostile parenting and disrupted child behavior associated with later child ADHD symptoms, controlling for concurrent adoptive mother ADHD symptoms. Results highlight the importance of genetically influenced child ADHD-related temperamental attributes on genetically unrelated maternal hostility that in turn links to later child ADHD symptoms. Implications for intervention programs focusing on early family processes and the precursors of child ADHD symptoms are discussed. © 2013 The Authors. Journal of Child Psychology and Psychiatry © 2013 Association for Child and Adolescent Mental Health.

[Calcium intake, serum vitamin D and obesity in children: is there an association?].

PubMed

Cunha, Kelly Aparecida da; Magalhães, Elma Izze da Silva; Loureiro, Laís Monteiro Rodrigues; Sant'Ana, Luciana Ferreira da Rocha; Ribeiro, Andréia Queiroz; Novaes, Juliana Farias de

2015-01-01

To evaluate the association between calcium intake and serum vitamin D levels and childhood obesity by an integrative review. The research was conducted in the databases PubMed/medLine, Science Direct and SciELO with 2001 to 2014 publications. We used the combined terms in English: "children" and "calcium" or "children" and "vitamin D" associated with the descriptors: "obesity", "adiposity" or "body fat" for all bases. Cross-sectional and cohort studies, as well as clinical trials, were included. Review articles or those that that have not addressed the association of interest were excluded. Eight articles were part of this review, five of which were related to calcium and three to vitamin D. Most studies had a longitudinal design. The analyzed studies found an association between calcium intake and obesity, especially when age and sex were considered. Inverse relationship between serum vitamin D and measures of adiposity in children has been observed and this association was influenced by the sex of the patient and by the seasons of the year. The studies reviewed showed an association between calcium and vitamin D with childhood obesity. Considering the possible protective effect of these micronutrients in relation to childhood obesity, preventive public health actions should be designed, with emphasis on nutritional education. Copyright © 2015 Associação de Pediatria de São Paulo. Publicado por Elsevier Editora Ltda. All rights reserved.

Hospital patient loyalty: causes and correlates.

PubMed

MacStravic, R S

1994-01-01

This study was designed to test whether factors associated with customer and employee loyalty are linked to hospital loyalty, and to measure the relative strength of the associations between traditional patient satisfaction factors and loyalty as compared to non-traditional factors.

Factors Associated with Teacher Delivery of a Classroom-Based Tier 2 Prevention Program

ERIC Educational Resources Information Center

Sutherland, Kevin S; Conroy, Maureen A; McLeod, Bryce D; Algina, James; Kunemund, Rachel L

2018-01-01

Teachers sometimes struggle to deliver evidence based programs designed to prevent and ameliorate chronic problem behaviors of young children with integrity. Identifying factors associated with variations in the quantity and quality of delivery is thus an important goal for the field. This study investigated factors associated with teacher…

Longitudinal Associations between Experienced Racial Discrimination and Depressive Symptoms in African American Adolescents

ERIC Educational Resources Information Center

English, Devin; Lambert, Sharon F.; Ialongo, Nicholas S.

2014-01-01

While recent evidence has indicated that experienced racial discrimination is associated with increased depressive symptoms for African American adolescents, most studies rely on cross-sectional and short-term longitudinal research designs. As a result, the direction and persistence of this association across time remains unclear. This article…

Nutrition warnings as front-of-pack labels: influence of design features on healthfulness perception and attentional capture.

PubMed

Cabrera, Manuel; Machín, Leandro; Arrúa, Alejandra; Antúnez, Lucía; Curutchet, María Rosa; Giménez, Ana; Ares, Gastón

2017-12-01

Warnings are a new directive front-of-pack (FOP) nutrition labelling scheme that highlights products with high content of key nutrients. The design of warnings influences their ability to catch consumers' attention and to clearly communicate their intended meaning, which are key determinants of their effectiveness. The aim of the present work was to evaluate the influence of design features of warnings as a FOP nutrition labelling scheme on perceived healthfulness and attentional capture. Five studies with a total of 496 people were carried out. In the first study, the association of colour and perceived healthfulness was evaluated in an online survey in which participants had to rate their perceived healthfulness of eight colours. In the second study, the influence of colour, shape and textual information on perceived healthfulness was evaluated using choice-conjoint analysis. The third study focused on implicit associations between two design features (shape and colour) on perceived healthfulness. The fourth and fifth studies used visual search to evaluate the influence of colour, size and position of the warnings on attentional capture. Perceived healthfulness was significantly influenced by shape, colour and textual information. Colour was the variable with the largest contribution to perceived healthfulness. Colour, size and position of the warnings on the labels affected attentional capture. Results from the experiments provide recommendations for the design of warnings to identify products with unfavourable nutrient profile.

Association between the BRCA2 rs144848 polymorphism and cancer susceptibility: a meta-analysis.

PubMed

Li, Qiuyan; Guan, Rongwei; Qiao, Yuandong; Liu, Chang; He, Ning; Zhang, Xuelong; Jia, Xueyuan; Sun, Haiming; Yu, Jingcui; Xu, Lidan

2017-06-13

The BRCA2 gene plays an important role in cancer carcinogenesis, and polymorphisms in this gene have been associated with cancer risk. The BRCA2 rs144848 polymorphism has been associated with several cancers, but results have been inconsistent. In the present study, a meta-analysis was performed to assess the association between the rs144848 polymorphism and cancer risk. Literature was searched from the databases of PubMed, Embase and Google Scholar before April 2016. The fixed or random effects model was used to calculate pooled odd ratios on the basis of heterogeneity. Meta-regression, sensitivity analysis, subgroup analysis and publication bias assessment were also performed using STATA 11.0 software according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2009. A total of 40 relevant studies from 30 publications including 34,911 cases and 48,329 controls were included in the final meta-analysis. Among them, 22 studies focused on breast cancer, seven on ovarian cancer, five on non-Hodgkin lymphoma, and the remaining six studies examined various other cancers. The meta-analysis results showed that there were significant associations between the rs144848 polymorphism and cancer risk in all genetic models. Stratified by cancer type, the rs144848 polymorphism was associated with non-Hodgkin lymphoma. Stratified by study design, the allele model was associated with breast cancer risk in population-based studies. The meta-analysis suggests that the BRCA2 rs144848 polymorphism may play a role in cancer risk. Further well-designed studies are warranted to confirm these results.

Waste incineration and adverse birth and neonatal outcomes: a systematic review.

PubMed

Ashworth, Danielle C; Elliott, Paul; Toledano, Mireille B

2014-08-01

Public concern about potential health risks associated with incineration has prompted studies to investigate the relationship between incineration and risk of cancer, and more recently, birth outcomes. We conducted a systematic review of epidemiologic studies evaluating the relationship between waste incineration and the risk of adverse birth and neonatal outcomes. Literature searches were performed within the MEDLINE database, through PubMed and Ovid interfaces, for the search terms; incineration, birth, reproduction, neonatal, congenital anomalies and all related terms. Here we discuss and critically evaluate the findings of these studies. A comprehensive literature search yielded fourteen studies, encompassing a range of outcomes (including congenital anomalies, birth weight, twinning, stillbirths, sex ratio and infant death), exposure assessment methods and study designs. For congenital anomalies most studies reported no association with proximity to or emissions from waste incinerators and "all anomalies", but weak associations for neural tube and heart defects and stronger associations with facial clefts and urinary tract defects. There is limited evidence for an association between incineration and twinning and no evidence of an association with birth weight, stillbirths or sex ratio, but this may reflect the sparsity of studies exploring these outcomes. The current evidence-base is inconclusive and often limited by problems of exposure assessment, possible residual confounding, lack of statistical power with variability in study design and outcomes. However, we identified a number of higher quality studies reporting significant positive relationships with broad groups of congenital anomalies, warranting further investigation. Future studies should address the identified limitations in order to help improve our understanding of any potential adverse birth outcomes associated with incineration, particularly focussing on broad groups of anomalies, to inform risk assessment and waste policy. Copyright © 2014 Elsevier Ltd. All rights reserved.

A Phenomenological Study Examining Classroom Teachers' Perceptions of the Roles of Professional School Counselors and School Counseling Programs in RAMP Designated Schools

ERIC Educational Resources Information Center

Vacchio, Calvin Bryan

2012-01-01

The purpose of this qualitative phenomenological study was to examine the perceptions of professional school counselors, and the comprehensive school counseling programs they implement, through the eyes of classroom teachers in schools that have received designation from the American School Counselor Association (ASCA) for actualizing a Recognized…

Design considerations for genetic linkage and association studies.

PubMed

Nsengimana, Jérémie; Bishop, D Timothy

2012-01-01

This chapter describes the main issues that genetic epidemiologists usually consider in the design of linkage and association studies. For linkage, we briefly consider the situation of rare, highly penetrant alleles showing a disease pattern consistent with Mendelian inheritance investigated through parametric methods in large pedigrees or with autozygosity mapping in inbred families, and we then turn our focus to the most common design, affected sibling pairs, of more relevance for common, complex diseases. Theoretical and more practical power and sample size calculations are provided as a function of the strength of the genetic effect being investigated. We also discuss the impact of other determinants of statistical power such as disease heterogeneity, pedigree, and genotyping errors, as well as the effect of the type and density of genetic markers. Linkage studies should be as large as possible to have sufficient power in relation to the expected genetic effect size. Segregation analysis, a formal statistical technique to describe the underlying genetic susceptibility, may assist in the estimation of the relevant parameters to apply, for instance. However, segregation analyses estimate the total genetic component rather than a single-locus effect. Locus heterogeneity should be considered when power is estimated and at the analysis stage, i.e. assuming smaller locus effect than the total the genetic component from segregation studies. Disease heterogeneity should be minimised by considering subtypes if they are well defined or by otherwise collecting known sources of heterogeneity and adjusting for them as covariates; the power will depend upon the relationship between the disease subtype and the underlying genotypes. Ultimately, identifying susceptibility alleles of modest effects (e.g. RR≤1.5) requires a number of families that seem unfeasible in a single study. Meta-analysis and data pooling between different research groups can provide a sizeable study, but both approaches require even a higher level of vigilance about locus and disease heterogeneity when data come from different populations. All necessary steps should be taken to minimise pedigree and genotyping errors at the study design stage as they are, for the most part, due to human factors. A two-stage design is more cost-effective than one stage when using short tandem repeats (STRs). However, dense single-nucleotide polymorphism (SNP) arrays offer a more robust alternative, and due to their lower cost per unit, the total cost of studies using SNPs may in the future become comparable to that of studies using STRs in one or two stages. For association studies, we consider the popular case-control design for dichotomous phenotypes, and we provide power and sample size calculations for one-stage and multistage designs. For candidate genes, guidelines are given on the prioritisation of genetic variants, and for genome-wide association studies (GWAS), the issue of choosing an appropriate SNP array is discussed. A warning is issued regarding the danger of designing an underpowered replication study following an initial GWAS. The risk of finding spurious association due to population stratification, cryptic relatedness, and differential bias is underlined. GWAS have a high power to detect common variants of high or moderate effect. For weaker effects (e.g. relative risk<1.2), the power is greatly reduced, particularly for recessive loci. While sample sizes of 10,000 or 20,000 cases are not beyond reach for most common diseases, only meta-analyses and data pooling can allow attaining a study size of this magnitude for many other diseases. It is acknowledged that detecting the effects from rare alleles (i.e. frequency<5%) is not feasible in GWAS, and it is expected that novel methods and technology, such as next-generation resequencing, will fill this gap. At the current stage, the choice of which GWAS SNP array to use does not influence the power in populations of European ancestry. A multistage design reduces the study cost but has less power than the standard one-stage design. If one opts for a multistage design, the power can be improved by jointly analysing the data from different stages for the SNPs they share. The estimates of locus contribution to disease risk from genome-wide scans are often biased, and relying on them might result in an underpowered replication study. Population structure has so far caused less spurious associations than initially feared, thanks to systematic ethnicity matching and application of standard quality control measures. Differential bias could be a more serious threat and must be minimised by strictly controlling all the aspects of DNA acquisition, storage, and processing.

Optimal designs for prediction studies of whiplash.

PubMed

Kamper, Steven J; Hancock, Mark J; Maher, Christopher G

2011-12-01

Commentary. To provide guidance for the design and interpretation of predictive studies of whiplash associated disorders (WAD). Numerous studies have sought to define and explain the clinical course and response to treatment of people with WAD. Design of these studies is often suboptimal, which can lead to biased findings and issues with interpreting the results. Literature review and commentary. Predictive studies can be grouped into four broad categories; studies of symptomatic course, studies that aim to identify factors that predict outcome, studies that aim to isolate variables that are causally responsible for outcome, and studies that aim to identify patients who respond best to particular treatments. Although the specific research question will determine the optimal methods, there are a number of generic features that should be incorporated into design of such studies. The aim of these features is to minimize bias, generate adequately precise prognostic estimates, and ensure generalizability of the findings. This paper provides a summary of important considerations in the design, conduct, and reporting of prediction studies in the field of whiplash.

Self-esteem and apparel satisfaction with appropriate clothing: value of product attributes and support groups for mastectomy survivors.

PubMed

Chowdhary, Usha; Ryan, Lenoraann

2003-08-01

The study examined use of appropriately designed clothing for special needs of postmastectomy women, including associations with self-esteem and satisfaction with certain apparel. The study was also designed to identify the person and product attributes valued by postmastectomy women while shopping for apparel items. A pre-posttest research design was used to examine the association of intervention, the self-esteem, and apparel satisfaction of the sample. Descriptive statistics were used for general information, as well as person and product attributes, and t tests were applied to test the two hypotheses. Analysis indicated that the intervention enhanced apparel satisfaction; however, the differences were not significant for self-esteem. The participants used support groups and evaluated several product attributes before making the apparel purchases. Implications for education, research, and service are discussed.

Case study: design, operation, maintenance and water quality management of sustainable storm water ponds for roof runoff.

PubMed

Scholz, Miklas

2004-12-01

The purpose of this case study was to optimise design, operation and maintenance guidelines, and to assess the water treatment potential of a storm water pond system after 15 months of operation. The system was based on a combined silt trap, attenuation pond and vegetated infiltration basin. This combination was used as the basis for construction of a roof water runoff system from a single domestic property. United Kingdom Building Research Establishment and Construction Industry Research and Information Association, and German Association for Water, Wastewater and Waste design guidelines were tested. These design guidelines failed because they did not consider local conditions. The infiltration function for the infiltration basin was logarithmic. Algal control techniques were successfully applied, and treatment of rainwater runoff from roofs was found to be largely unnecessary for recycling (e.g., watering plants). However, seasonal and diurnal variations of biochemical oxygen demand, dissolved oxygen and pH were recorded.

Modeling of the whispering gallery mode in microdisk and microgear resonators using a Toeplitz matrix formalism for single-photon source

NASA Astrophysics Data System (ADS)

Attia, Moez; Gueddana, Amor; Chatta, Rihab; Morand, Alain

2013-09-01

The work presented in this paper develops a new formalism to design microdisks and microgears structures. The main objective is to study the optics and geometrics parameters influence on the microdisks and microgears structures resonance behavior. This study is conducted to choice a resonance structure with height quality factor Q to be associated with Quantum dot to form a single photon source. This new method aims to design resonant structures that are simpler and requires less computing performances than FDTD and Floquet Block methods. This formalism is based on simplifying Fourier transformed and using toeplitz matrix writing. This new writing allows designing all kind of resonance structures with any defect and any modification. In other study we have design a quantum dot emitting a photon at 1550 nm of the fundamental mode, but the quantum dot emits other photons at other wavelengths. The focus of the resonant structure and the quantum dot association is the resonance of the photon at 1550 nm and the elimination of all other photons with others energies. The quantum dot studied in [1] is an InAs/GaAs quantum dot, we design an GaAS microdisk and microgear and we compare the quality factor Q of this two structures and we conclude that the microgear is more appropriated to be associate to the quantum dot and increase the probability P1 to obtain a single photon source at 1550 nm and promotes the obtaining of single photon. The performance improving of the resonant structure is able to increase the success of quantum applications such as quantum gates based on single photon source.

Predictors of Manuscript Publication: A Review of Obstetrics and Gynecology Society Meeting Abstracts.

PubMed

Muffly, Tyler M; Webster, Kelsey; Conageski, Christine; Guiahi, Maryam

2016-01-01

The authors attempted to understand the manuscript publication rate and predictors of publication of abstracts presented at obstetrical and gynecologic society meetings. In 2013, the authors obtained the text of all 2005 abstracts presented at a major generalist- and fellowship-associated society meetings. In this cross-sectional study, a search was completed for publication and identified possible predictors. The authors examined 1405 abstracts; the overall full-text publication rate was 54% (755/1405 publications) and the mean (SD) time to publication was 25.6 (20.8) months. Variables associated with publication in multivariable analysis included number of abstract authors (odds ratio [OR], 1.7; confidence interval [CI], 1.0-1.2), first authorship in American Congress of Obstetricians and Gynecologists district IV (OR, 1.7; CI, 0.9-3.1), prospective design (OR, 1.7; CI, 0.9-3.1), multicenter design (OR, 2.5; CI, 1.3-4.9), and oral presentation (OR, 3.2; CI, 1.4-7.3). Abstracts from specialty meetings were more likely to have these characteristics and, thus, higher publication rates. This study can guide project development for young researchers by informing them of key study design features associated with manuscript publication.

Use of simulation-based education to improve outcomes of central venous catheterization: a systematic review and meta-analysis.

PubMed

Ma, Irene W Y; Brindle, Mary E; Ronksley, Paul E; Lorenzetti, Diane L; Sauve, Reg S; Ghali, William A

2011-09-01

Central venous catheterization (CVC) is increasingly taught by simulation. The authors reviewed the literature on the effects of simulation training in CVC on learner and clinical outcomes. The authors searched computerized databases (1950 to May 2010), reference lists, and considered studies with a control group (without simulation education intervention). Two independent assessors reviewed the retrieved citations. Independent data abstraction was performed on study design, study quality score, learner characteristics, sample size, components of interventional curriculum, outcomes assessed, and method of assessment. Learner outcomes included performance measures on simulators, knowledge, and confidence. Patient outcomes included number of needle passes, arterial puncture, pneumothorax, and catheter-related infections. Twenty studies were identified. Simulation-based education was associated with significant improvements in learner outcomes: performance on simulators (standardized mean difference [SMD] 0.60 [95% CI 0.45 to 0.76]), knowledge (SMD 0.60 [95% CI 0.35 to 0.84]), and confidence (SMD 0.41 [95% CI 0.30 to 0.53] for studies with single-group pretest and posttest design; SMD 0.52 (95% CI 0.23 to 0.81) for studies with nonrandomized, two-group design). Furthermore, simulation-based education was associated with improved patient outcomes, including fewer needle passes (SMD -0.58 [95% CI -0.95 to -0.20]), and pneumothorax (relative risk 0.62 [95% CI 0.40 to 0.97]), for studies with nonrandomized, two-group design. However, simulation-based training was not associated with a significant reduction in risk of either arterial puncture or catheter-related infections. Despite some limitations in the literature reviewed, evidence suggests that simulation-based education for CVC provides benefits in learner and select clinical outcomes.

Sedentary behaviour and adiposity in youth: a systematic review of reviews and analysis of causality.

PubMed

Biddle, Stuart J H; García Bengoechea, Enrique; Wiesner, Glen

2017-03-28

Sedentary behaviour (sitting time) has becoming a very popular topic for research and translation since early studies on TV viewing in children in the 1980s. The most studied area for sedentary behaviour health outcomes has been adiposity in young people. However, the literature is replete with inconsistencies. We conducted a systematic review of systematic reviews and meta-analyses to provide a comprehensive analysis of evidence and state-of-the-art synthesis on whether sedentary behaviours are associated with adiposity in young people, and to what extent any association can be considered 'causal'. Searches yielded 29 systematic reviews of over 450 separate papers. We analysed results by observational (cross-sectional and longitudinal) and intervention designs. Small associations were reported for screen time and adiposity from cross-sectional evidence, but associations were less consistent from longitudinal studies. Studies using objective accelerometer measures of sedentary behaviour yielded null associations. Most studies assessed BMI/BMI-z. Interventions to reduce sedentary behaviour produced modest effects for weight status and adiposity. Accounting for effects from sedentary behaviour reduction alone is difficult as many interventions included additional changes in behaviour, such as physical activity and dietary intake. Analysis of causality guided by the classic Bradford Hill criteria concluded that there is no evidence for a causal association between sedentary behaviour and adiposity in youth, although a small dose-response association exists. Associations between sedentary behaviour and adiposity in children and adolescents are small to very small and there is little to no evidence that this association is causal. This remains a complex field with different exposure and outcome measures and research designs. But claims for 'clear' associations between sedentary behaviour and adiposity in youth, and certainly for causality, are premature or misguided.

Genome-wide association studies and epigenome-wide association studies go together in cancer control

PubMed Central

Verma, Mukesh

2016-01-01

Completion of the human genome a decade ago laid the foundation for: using genetic information in assessing risk to identify individuals and populations that are likely to develop cancer, and designing treatments based on a person's genetic profiling (precision medicine). Genome-wide association studies (GWAS) completed during the past few years have identified risk-associated single nucleotide polymorphisms that can be used as screening tools in epidemiologic studies of a variety of tumor types. This led to the conduct of epigenome-wide association studies (EWAS). This article discusses the current status, challenges and research opportunities in GWAS and EWAS. Information gained from GWAS and EWAS has potential applications in cancer control and treatment. PMID:27079684

Parental, Behavioral, and Psychological Factors Associated with Cigarette Smoking among Secondary School Students in Nanjing, China

ERIC Educational Resources Information Center

Li, Xiaoming; Mao, Rong; Stanton, Bonita; Zhao, Qun

2010-01-01

We designed this study to assess parental, behavioral, and psychological factors associated with tobacco use among Chinese adolescents. The data were collected from 995 middle school students in Nanjing, China. Both smoking experimentation and current smoking (smoking in the past 30 days) were assessed among the study sample. Psychosocial measures…

Associating Animations with Concrete Models to Enhance Students' Comprehension of Different Visual Representations in Organic Chemistry

ERIC Educational Resources Information Center

Al-Balushi, Sulaiman M.; Al-Hajri, Sheikha H.

2014-01-01

The purpose of the current study is to explore the impact of associating animations with concrete models on eleventh-grade students' comprehension of different visual representations in organic chemistry. The study used a post-test control group quasi-experimental design. The experimental group (N = 28) used concrete models, submicroscopic…

EPISODIC AIR POLLUTION IS ASSOCIATED WITH INCREASED DNA FRAGMENTATION IN HUMAN SPERM WITHOUT OTHER CHANGES IN SEMEN QUALITY

EPA Science Inventory

This study was motivated by a previous report of associations between episodes of high air pollution and alterations in semen quality in young men living in an industrial district of the Czech Republic. Using a repeated measures study design, a cohort of men from this district we...

Factors Associated with Women's Antenatal Plans to Use a Baby Walker: A Cross Sectional Study

ERIC Educational Resources Information Center

Illingworth, Rachel; Kendrick, Denise; Collier, Jacqueline; Woods, Amanda; Wattse, Kim; Dewey, Michael; Chen, Chih-Mei

2006-01-01

Objective: The objective of these analyses was to explore maternal antenatal decisions about baby walker use, factors associated with these decisions and the relationship between antenatal plans to use a walker and postnatal walker use. Design: Cross sectional study. Setting: Mothers-to-be (n = 1174) participating in a cluster randomised…

Associations between Finnish 9th Grade Students' School Perceptions, Health Behaviors, and Family Factors

ERIC Educational Resources Information Center

Ilona, Haapasalo; Raili, Valimaa; Lasse, Kannas

2012-01-01

Purpose: The aim of this study was to examine the associations between students' perceptions of the psychosocial school environment, health-compromising behaviours, and selected family factors. The analyses were based on data provided for the Health Behaviour in School-aged Children Study (2006). Design/methodology/approach: The data were obtained…

The Association between Changes in Health Status and Nursing Home Resident Quality of Life

ERIC Educational Resources Information Center

Degenholtz, Howard B.; Rosen, Jules; Castle, Nicholas; Mittal, Vikas; Liu, Darren

2008-01-01

Purpose: Previous research on nursing home resident quality of life (QOL) has mainly been cross-sectional. This study examined the association between changes in QOL and changes in resident clinical factors. Design and Methods: A longitudinal study of resident QOL was conducted in two nursing homes. Self-report interviews using a multidimensional…

76 FR 68741 - Notice of Intent To Prepare a Draft Environmental Impact Statement/Environment Impact Report...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-07

... studies that are underway. 5. Scoping Process: The Corps and County Parks will jointly conduct a series of... development of the EIS/EIR and associated technical studies are being completed to determine the Agency... Association of Governments (SANDAG). The EIR/EIS is currently evaluating three alternative restoration designs...

An Analysis of the Association between Perceived Discrimination and Self-Reported Health among University Students in Southwest Florida

ERIC Educational Resources Information Center

McFarland, Renee L.

2013-01-01

The experience of discrimination is a complex phenomenon. At present, there are few studies that have captured the experience of discrimination on a predominately white university campus. This study was designed to investigate the association between perceived discrimination and self-reported health outcomes among university students in Southwest…

Return on investment in healthcare leadership development programs.

PubMed

Jeyaraman, Maya M; Qadar, Sheikh Muhammad Zeeshan; Wierzbowski, Aleksandra; Farshidfar, Farnaz; Lys, Justin; Dickson, Graham; Grimes, Kelly; Phillips, Leah A; Mitchell, Jonathan I; Van Aerde, John; Johnson, Dave; Krupka, Frank; Zarychanski, Ryan; Abou-Setta, Ahmed M

2018-02-05

Purpose Strong leadership has been shown to foster change, including loyalty, improved performance and decreased error rates, but there is a dearth of evidence on effectiveness of leadership development programs. To ensure a return on the huge investments made, evidence-based approaches are needed to assess the impact of leadership on health-care establishments. As a part of a pan-Canadian initiative to design an effective evaluative instrument, the purpose of this paper was to identify and summarize evidence on health-care outcomes/return on investment (ROI) indicators and metrics associated with leadership quality, leadership development programs and existing evaluative instruments. Design/methodology/approach The authors performed a scoping review using the Arksey and O'Malley framework, searching eight databases from 2006 through June 2016. Findings Of 11,868 citations screened, the authors included 223 studies reporting on health-care outcomes/ROI indicators and metrics associated with leadership quality (73 studies), leadership development programs (138 studies) and existing evaluative instruments (12 studies). The extracted ROI indicators and metrics have been summarized in detail. Originality/value This review provides a snapshot in time of the current evidence on ROI indicators and metrics associated with leadership. Summarized ROI indicators and metrics can be used to design an effective evaluative instrument to assess the impact of leadership on health-care organizations.

Drug development for exceptionally rare metabolic diseases: challenging but not impossible

PubMed Central

2013-01-01

Background We studied to what extent the level of scientific knowledge on exceptionally rare metabolic inherited diseases and their potential orphan medicinal products is associated with sponsors deciding to apply for an orphan designation at the US Food and Drug Administration (FDA) or the European Medicines Agency (EMA). Methods All metabolic diseases with a genetic cause and prevalence of less than 10 patients per 1 million of the population were selected from the ‘Orphanet database of Rare diseases’. The outcome of interest was the application for an orphan designation at FDA or EMA. The level of publicly available knowledge of the disease and drug candidate before an orphan designation application was defined as whether the physiological function corresponding with the pathologic gene and initiation of the pathophysiological pathway was known, whether an appropriate animal study was identified for the disease, whether preclinical proof of concept was ascertained and the availability of data in humans. Other determinants included in the study were metabolic disease class, the prevalence of the disease, prognosis and time of first description of the disease in the literature. Univariate relative risks (RRs) and 95% confidence intervals (CIs) of an orphan designation application were calculated for each of these determinants. In addition, a multivariate Cox regression analysis was conducted (Forward LR). Results In total, 166 rare metabolic genetic diseases were identified and included in the analysis. For only 42 (25%) of the diseases an orphan designation application was submitted at either FDA or EMA before January 2012. The multivariate analysis identified preclinical proof of concept of a potential medicinal product as major knowledge related determinant associated with an orphan designation application (RRadj 3.9, 95% CI 1.9-8.3) and confirmed that prevalence of the disease is also associated with filing an application for an orphan designation (RRadj 2.8, 95% CI 1.4-5.4). Conclusion For only one out of four known exceptionally rare metabolic inherited diseases sponsors applied for an orphan designation at FDA or EMA. These applications were found to be associated with the prevalence of the rare disease and the level of available scientific knowledge on the proof of concept linking possible drug candidates to the disease of interest. PMID:24237580

Methodologic considerations in the design and analysis of nested case-control studies: association between cytokines and postoperative delirium.

PubMed

Ngo, Long H; Inouye, Sharon K; Jones, Richard N; Travison, Thomas G; Libermann, Towia A; Dillon, Simon T; Kuchel, George A; Vasunilashorn, Sarinnapha M; Alsop, David C; Marcantonio, Edward R

2017-06-06

The nested case-control study (NCC) design within a prospective cohort study is used when outcome data are available for all subjects, but the exposure of interest has not been collected, and is difficult or prohibitively expensive to obtain for all subjects. A NCC analysis with good matching procedures yields estimates that are as efficient and unbiased as estimates from the full cohort study. We present methodological considerations in a matched NCC design and analysis, which include the choice of match algorithms, analysis methods to evaluate the association of exposures of interest with outcomes, and consideration of overmatching. Matched, NCC design within a longitudinal observational prospective cohort study in the setting of two academic hospitals. Study participants are patients aged over 70 years who underwent scheduled major non-cardiac surgery. The primary outcome was postoperative delirium from in-hospital interviews and medical record review. The main exposure was IL-6 concentration (pg/ml) from blood sampled at three time points before delirium occurred. We used nonparametric signed ranked test to test for the median of the paired differences. We used conditional logistic regression to model the risk of IL-6 on delirium incidence. Simulation was used to generate a sample of cohort data on which unconditional multivariable logistic regression was used, and the results were compared to those of the conditional logistic regression. Partial R-square was used to assess the level of overmatching. We found that the optimal match algorithm yielded more matched pairs than the greedy algorithm. The choice of analytic strategy-whether to consider measured cytokine levels as the predictor or outcome-- yielded inferences that have different clinical interpretations but similar levels of statistical significance. Estimation results from NCC design using conditional logistic regression, and from simulated cohort design using unconditional logistic regression, were similar. We found minimal evidence for overmatching. Using a matched NCC approach introduces methodological challenges into the study design and data analysis. Nonetheless, with careful selection of the match algorithm, match factors, and analysis methods, this design is cost effective and, for our study, yields estimates that are similar to those from a prospective cohort study design.

Analytical trade study of the STS payload environment. [design analysis and cost estimates for noise reduction devices for space shuttle orbiter payloads

NASA Technical Reports Server (NTRS)

Rader, W. P.; Barrett, S.; Raratono, J.; Payne, K. R.

1976-01-01

The current predicted acoustic environment for the shuttle orbiter payload bay will produce random vibration environments for payload components and subsystems which potentially will result in design, weight and cost penalties if means of protecting the payloads are not developed. Results are presented of a study to develop, through design and cost effectiveness trade studies, conceptual noise suppression device designs for space shuttle payloads. The impact of noise suppression on environmental levels and associated test costs, and on test philosophy for the various payload classes is considered with the ultimate goal of reducing payload test costs. Conclusions and recommendations are presented.

Design, innovation, and rural creative places: Are the arts the cherry on top, or the secret sauce?

PubMed

Wojan, Timothy R; Nichols, Bonnie

2018-01-01

Creative class theory explains the positive relationship between the arts and commercial innovation as the mutual attraction of artists and other creative workers by an unobserved creative milieu. This study explores alternative theories for rural settings, by analyzing establishment-level survey data combined with data on the local arts scene. The study identifies the local contextual factors associated with a strong design orientation, and estimates the impact that a strong design orientation has on the local economy. Data on innovation and design come from a nationally representative sample of establishments in tradable industries. Latent class analysis allows identifying unobserved subpopulations comprised of establishments with different design and innovation orientations. Logistic regression allows estimating the association between an establishment's design orientation and local contextual factors. A quantile instrumental variable regression allows assessing the robustness of the logistic regression results with respect to endogeneity. An estimate of design orientation at the local level derived from the survey is used to examine variation in economic performance during the period of recovery from the Great Recession (2010-2014). Three distinct innovation (substantive, nominal, and non-innovators) and design orientations (design-integrated, "design last finish," and no systematic approach to design) are identified. Innovation- and design-intensive establishments were identified in both rural and urban areas. Rural design-integrated establishments tended to locate in counties with more highly educated workforces and containing at least one performing arts organization. A quantile instrumental variable regression confirmed that the logistic regression result is robust to endogeneity concerns. Finally, rural areas characterized by design-integrated establishments experienced faster growth in wages relative to rural areas characterized by establishments using no systematic approach to design.

Design, innovation, and rural creative places: Are the arts the cherry on top, or the secret sauce?

PubMed Central

Nichols, Bonnie

2018-01-01

Objective Creative class theory explains the positive relationship between the arts and commercial innovation as the mutual attraction of artists and other creative workers by an unobserved creative milieu. This study explores alternative theories for rural settings, by analyzing establishment-level survey data combined with data on the local arts scene. The study identifies the local contextual factors associated with a strong design orientation, and estimates the impact that a strong design orientation has on the local economy. Method Data on innovation and design come from a nationally representative sample of establishments in tradable industries. Latent class analysis allows identifying unobserved subpopulations comprised of establishments with different design and innovation orientations. Logistic regression allows estimating the association between an establishment’s design orientation and local contextual factors. A quantile instrumental variable regression allows assessing the robustness of the logistic regression results with respect to endogeneity. An estimate of design orientation at the local level derived from the survey is used to examine variation in economic performance during the period of recovery from the Great Recession (2010–2014). Results Three distinct innovation (substantive, nominal, and non-innovators) and design orientations (design-integrated, “design last finish,” and no systematic approach to design) are identified. Innovation- and design-intensive establishments were identified in both rural and urban areas. Rural design-integrated establishments tended to locate in counties with more highly educated workforces and containing at least one performing arts organization. A quantile instrumental variable regression confirmed that the logistic regression result is robust to endogeneity concerns. Finally, rural areas characterized by design-integrated establishments experienced faster growth in wages relative to rural areas characterized by establishments using no systematic approach to design. PMID:29489884

Radar cross section studies/compact range research

NASA Technical Reports Server (NTRS)

Burnside, W. D.; Dominek, A. K.; Gupta, I. J.; Newman, E. H.; Pathak, P. H.; Peters, L., Jr.

1989-01-01

Achievements in advancing the state-of-the-art in the measurement, control, and analysis of electromagnetic scattering from general aerodynamic targets are summarized. The major topics associated with this study include: (1) electromagnetic scattering analysis; (2) indoor scattering measurement systems; (3) RCS control; (4) waveform processing techniques; (5) material scattering and design studies; (6) design and evaluation of standard targets; and (7) antenna studies. Progress in each of these areas is reported and related publications are listed.

Associations of welding and manganese exposure with Parkinson disease

PubMed Central

Borenstein, Amy R.; Nelson, Lorene M.

2012-01-01

Objective: To examine associations of welding and manganese exposure with Parkinson disease (PD) using meta-analyses of data from cohort, case-control, and mortality studies. Methods: Epidemiologic studies related to welding or manganese exposure and PD were identified in a PubMed search, article references, published reviews, and abstracts. Inclusion criteria were 1) cohort, case-control, or mortality study with relative risk (RR), odds ratio (OR), or mortality OR (MOR) and 95 confidence intervals (95% CI); 2) RR, OR, and MOR matched or adjusted for age and sex; 3) valid study design and analysis. When participants of a study were a subgroup of those in a larger study, only results of the larger study were included to assure independence of datasets. Pooled RR/OR estimates and 95% CIs were obtained using random effects models; heterogeneity of study effects were evaluated using the Q statistic and I2 index in fixed effect models. Results: Thirteen studies met inclusion criteria for the welding meta-analysis and 3 studies for the manganese exposure meta-analysis. The pooled RR for the association between welding and PD for all study designs was 0.86 (95% CI 0.80–0.92), with absence of between-study heterogeneity (I2 = 0.0). Effect measures for cohort, case-control, and mortality studies were similar (0.91, 0.82, 0.87). For the association between manganese exposure and PD, the pooled OR was 0.76 (95% CI 0.41–1.42). Conclusions: Welding and manganese exposure are not associated with increased PD risk. Possible explanations for the inverse association between welding and PD include confounding by smoking, healthy worker effect, and hormesis. PMID:22965675

Using population mixtures to optimize the utility of genomic databases: linkage disequilibrium and association study design in India.

PubMed

Pemberton, T J; Jakobsson, M; Conrad, D F; Coop, G; Wall, J D; Pritchard, J K; Patel, P I; Rosenberg, N A

2008-07-01

When performing association studies in populations that have not been the focus of large-scale investigations of haplotype variation, it is often helpful to rely on genomic databases in other populations for study design and analysis - such as in the selection of tag SNPs and in the imputation of missing genotypes. One way of improving the use of these databases is to rely on a mixture of database samples that is similar to the population of interest, rather than using the single most similar database sample. We demonstrate the effectiveness of the mixture approach in the application of African, European, and East Asian HapMap samples for tag SNP selection in populations from India, a genetically intermediate region underrepresented in genomic studies of haplotype variation.

A COMPARISON OF ANALYSIS UNITS FOR ASSOCIATING LYME DISEASE WITH FOREST-EDGE HABITAT

EPA Science Inventory

This study assessed the relationship between land-cover pattern and Lyme disease incidence rate when modeled under three designs for data aggregation. Incidence rates were calculated from passive surveillance data reported in 12 Maryland counties during 1996 – 2000. A design usin...

Fostering creativity in product and service development: validation in the domain of information technology.

PubMed

Zeng, Liang; Proctor, Robert W; Salvendy, Gavriel

2011-06-01

This research is intended to empirically validate a general model of creative product and service development proposed in the literature. A current research gap inspired construction of a conceptual model to capture fundamental phases and pertinent facilitating metacognitive strategies in the creative design process. The model also depicts the mechanism by which design creativity affects consumer behavior. The validity and assets of this model have not yet been investigated. Four laboratory studies were conducted to demonstrate the value of the proposed cognitive phases and associated metacognitive strategies in the conceptual model. Realistic product and service design problems were used in creativity assessment to ensure ecological validity. Design creativity was enhanced by explicit problem analysis, whereby one formulates problems from different perspectives and at different levels of abstraction. Remote association in conceptual combination spawned more design creativity than did near association. Abstraction led to greater creativity in conducting conceptual expansion than did specificity, which induced mental fixation. Domain-specific knowledge and experience enhanced design creativity, indicating that design can be of a domain-specific nature. Design creativity added integrated value to products and services and positively influenced customer behavior. The validity and value of the proposed conceptual model is supported by empirical findings. The conceptual model of creative design could underpin future theory development. Propositions advanced in this article should provide insights and approaches to facilitate organizations pursuing product and service creativity to gain competitive advantage.

Personal use of hair dyes and the risk of bladder cancer: results of a meta-analysis.

PubMed Central

Huncharek, Michael; Kupelnick, Bruce

2005-01-01

OBJECTIVE: This study examined the methodology of observational studies that explored an association between personal use of hair dye products and the risk of bladder cancer. METHODS: Data were pooled from epidemiological studies using a general variance-based meta-analytic method that employed confidence intervals. The outcome of interest was a summary relative risk (RRs) reflecting the risk of bladder cancer development associated with use of hair dye products vs. non-use. Sensitivity analyses were performed to explain any observed statistical heterogeneity and to explore the influence of specific study characteristics of the summary estimate of effect. RESULTS: Initially combining homogenous data from six case-control and one cohort study yielded a non-significant RR of 1.01 (0.92, 1.11), suggesting no association between hair dye use and bladder cancer development. Sensitivity analyses examining the influence of hair dye type, color, and study design on this suspected association showed that uncontrolled confounding and design limitations contributed to a spurious non-significant summary RR. The sensitivity analyses yielded statistically significant RRs ranging from 1.22 (1.11, 1.51) to 1.50 (1.30, 1.98), indicating that personal use of hair dye products increases bladder cancer risk by 22% to 50% vs. non-use. CONCLUSION: The available epidemiological data suggest an association between personal use of hair dye products and increased risk of bladder cancer. PMID:15736329

Microwave monolithic integrated circuit development for future spaceborne phased array antennas

NASA Astrophysics Data System (ADS)

Anzic, G.; Kascak, T. J.; Downey, A. N.; Liu, D. C.; Connolly, D. J.

1983-12-01

The development of fully monolithic gallium arsenide (GaAs) receive and transmit modules suitable for phased array antenna applications in the 30/20 gigahertz bands is presented. Specifications and various design approaches to achieve the design goals are described. Initial design and performance of submodules and associated active and passive components are presented. A tradeoff study summary is presented highlighting the advantages of distributed amplifier approach compared to the conventional single power source designs.

Microwave monolithic integrated circuit development for future spaceborne phased array antennas

NASA Technical Reports Server (NTRS)

Anzic, G.; Kascak, T. J.; Downey, A. N.; Liu, D. C.; Connolly, D. J.

1983-01-01

The development of fully monolithic gallium arsenide (GaAs) receive and transmit modules suitable for phased array antenna applications in the 30/20 gigahertz bands is presented. Specifications and various design approaches to achieve the design goals are described. Initial design and performance of submodules and associated active and passive components are presented. A tradeoff study summary is presented highlighting the advantages of distributed amplifier approach compared to the conventional single power source designs.

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

Labby, Z.

Physicists are often expected to have a solid grounding in experimental design and statistical analysis, sometimes filling in when biostatisticians or other experts are not available for consultation. Unfortunately, graduate education on these topics is seldom emphasized and few opportunities for continuing education exist. Clinical physicists incorporate new technology and methods into their practice based on published literature. A poor understanding of experimental design and analysis could Result in inappropriate use of new techniques. Clinical physicists also improve current practice through quality initiatives that require sound experimental design and analysis. Academic physicists with a poor understanding of design and analysismore » may produce ambiguous (or misleading) results. This can Result in unnecessary rewrites, publication rejection, and experimental redesign (wasting time, money, and effort). This symposium will provide a practical review of error and uncertainty, common study designs, and statistical tests. Instruction will primarily focus on practical implementation through examples and answer questions such as: where would you typically apply the test/design and where is the test/design typically misapplied (i.e., common pitfalls)? An analysis of error and uncertainty will also be explored using biological studies and associated modeling as a specific use case. Learning Objectives: Understand common experimental testing and clinical trial designs, what questions they can answer, and how to interpret the results Determine where specific statistical tests are appropriate and identify common pitfalls Understand the how uncertainty and error are addressed in biological testing and associated biological modeling.« less

Food reinforcement and delay discounting in zBMI-discordant siblings ☆

PubMed Central

Feda, Denise M.; Roemmich, James N.; Roberts, April; Epstein, Leonard H.

2014-01-01

Objective The interaction of food reinforcement and the inability to delay gratification are related to adult energy intake and obesity. This study was designed to test the association of sibling pair differences in relative reinforcing efficacy of food and delay discounting on sibling pair differences in zBMI scores of same-gender zBMI-discordant siblings. Design and methods We tested main and interactive relationships between delay discounting and relative reinforcing efficacy of food on zBMI discordance in 14 zBMI-discordant biological sibling pairs (6 female pairs) using a discordant sibling study design. Results Sibling pair differences in relative reinforcing efficacy of food were associated with sibling pair differences in zBMI (p = 0.046); this effect was moderated by delay discounting (p < 0.002). Sibling pairs with greater differences in relative reinforcing efficacy and delay discounting had greater differences in zBMI. Conclusions The combination of greater sibling pair differences in delay discounting and relative reinforcing efficacy is associated with greater discordance in zBMI in adolescent sibling pairs. PMID:25464024

Multifactor dimensionality reduction reveals a three-locus epistatic interaction associated with susceptibility to pulmonary tuberculosis.

PubMed

Collins, Ryan L; Hu, Ting; Wejse, Christian; Sirugo, Giorgio; Williams, Scott M; Moore, Jason H

2013-02-18

Identifying high-order genetics associations with non-additive (i.e. epistatic) effects in population-based studies of common human diseases is a computational challenge. Multifactor dimensionality reduction (MDR) is a machine learning method that was designed specifically for this problem. The goal of the present study was to apply MDR to mining high-order epistatic interactions in a population-based genetic study of tuberculosis (TB). The study used a previously published data set consisting of 19 candidate single-nucleotide polymorphisms (SNPs) in 321 pulmonary TB cases and 347 healthy controls from Guniea-Bissau in Africa. The ReliefF algorithm was applied first to generate a smaller set of the five most informative SNPs. MDR with 10-fold cross-validation was then applied to look at all possible combinations of two, three, four and five SNPs. The MDR model with the best testing accuracy (TA) consisted of SNPs rs2305619, rs187084, and rs11465421 (TA = 0.588) in PTX3, TLR9 and DC-Sign, respectively. A general 1000-fold permutation test of the null hypothesis of no association confirmed the statistical significance of the model (p = 0.008). An additional 1000-fold permutation test designed specifically to test the linear null hypothesis that the association effects are only additive confirmed the presence of non-additive (i.e. nonlinear) or epistatic effects (p = 0.013). An independent information-gain measure corroborated these results with a third-order epistatic interaction that was stronger than any lower-order associations. We have identified statistically significant evidence for a three-way epistatic interaction that is associated with susceptibility to TB. This interaction is stronger than any previously described one-way or two-way associations. This study highlights the importance of using machine learning methods that are designed to embrace, rather than ignore, the complexity of common diseases such as TB. We recommend future studies of the genetics of TB take into account the possibility that high-order epistatic interactions might play an important role in disease susceptibility.

How Does Psychosocial Behavior Contribute to Cognitive Health in Old Age?

PubMed Central

Wilson, Robert S.; Bennett, David A.

2017-01-01

With the aging of the U.S. population, the number of cognitively disabled persons is expected to substantially increase in coming decades, underscoring the urgent need for effective interventions. Here, we review the current evidence linking psychosocial factors to late-life cognitive loss and consider the study design needed to illuminate the biologic bases of the associations. We then examine an ongoing study that includes several of the key design elements, the Rush Memory and Aging Project. In this longitudinal clinical-pathological cohort study, indicators of personality, social connectedness, and psychological well-being were shown to predict late-life cognitive outcomes. Participants who died underwent a uniform neuropathologic examination to quantify common dementia-related pathologies. Some psychosocial indicators were associated with cerebral infarction; some indicators modified the association of neurodegenerative pathologies with cognitive loss; and the association of some indicators with cognitive outcomes appears to be independent of the pathologies traditionally associated with late-life dementia. These findings suggest that psychosocial behavior influences late-life cognitive health through multiple neurobiologic mechanisms. A better understanding of these mechanisms may lead to novel strategies for preserving cognitive health in old age. PMID:28545247

Risk factors associated with asbestos-related diseases: a community-based case-control study.

PubMed

Rosell-Murphy, Magdalena-Isabel; Abós-Herràndiz, Rafael; Olivella, Josep Tarrés; Alberti-Casas, Constança; Allas, Isabel García; Artés, Xavier Martinez; Günther, Ilona Krier; Malet, Isidre Grimau; Martínez, Ramon Orriols; Canela-Soler, Jaume

2013-08-06

Asbestos is a first level carcinogen. However, few epidemiological studies analyse the risk and protective factors associated with asbestos-related diseases and follow up these conditions in the general population. Pleural mesothelioma, caused by inhalation of asbestos fibres at work, at home or in the environment, is the most representative asbestos-related disease.The objectives of this study are to analyse the risk and protective factors associated with asbestos-related diseases and to investigate the incidence of new clinical manifestations in patients already diagnosed with some form of ARD. We have designed a matched case-control study with follow up of both cohorts from a population of a health district of the Barcelona province that has been exposed to asbestos for a period of 90 years. A better understanding of asbestos-related diseases should improve i) the clinical and epidemiological follow up of patients with this condition; ii) the design of new treatment strategies; iii) and the development of preventive activities. At the end of the study, the two cohorts created in this study (affected cases and healthy controls) will constitute the basis for future research.

The associations between diet quality, body mass index (BMI) and health and activity limitation index (HALEX) in the Geisinger Rural Aging Study (GRAS)

USDA-ARS?s Scientific Manuscript database

Objectives To determine the associations between diet quality, body mass index (BMI), and health-related quality of life (HRQOL) as assessed by the health and activity limitation index (HALex) in older adults. Design Multivariate linear regression models were used to analyze associations between Di...

Antidepressants and testicular cancer: cause versus association.

PubMed

Andrade, Chittaranjan

2014-03-01

A data mining study that examined associations between 105 drugs and 55 cancer sites found significant associations between 2 selective serotonin reuptake inhibitors (fluoxetine and paroxetine) and testicular cancer. The study suggested several reasons why these associations merited further investigation. A later study tested specific relationships between 12 antidepressant drugs and testicular cancer and subtypes thereof; whereas significant relationships were again found, these disappeared after adjusting for confounding variables. These 2 studies are educative because they illustrate how false-positive results can easily arise in exploratory research and how confounding may be responsible for statistically significant relationships in study designs that are not randomized controlled trials. © Copyright 2014 Physicians Postgraduate Press, Inc.

The Biomarkers of Exposure and Effect in Agriculture (BEEA) Study: Rationale, design, methods, and participant characteristics

EPA Science Inventory

Agricultural exposures including pesticides, endotoxin, and allergens have been associated with risk of various cancers and other chronic diseases, although the biological mechanisms underlying these associations are generally unclear. To facilitate future molecular epidemiologic...

TREAT (TREe-based Association Test)

Cancer.gov

TREAT is an R package for detecting complex joint effects in case-control studies. The test statistic is derived from a tree-structure model by recursive partitioning the data. Ultra-fast algorithm is designed to evaluate the significance of association between candidate gene and disease outcome

Ground Operations Aerospace Language (GOAL). Volume 1: Study overview

NASA Technical Reports Server (NTRS)

1973-01-01

A series of NASA and Contractor studies sponsored by NASA/KSC resulted in a specification for the Ground Operations Aerospace Language (GOAL). The Cape Kennedy Facility of the IBM Corporation was given the responsibility, under existing contracts, to perform an analysis of the Language Specification, to design and develop a GOAL Compiler, to provide a specification for a data bank, to design and develop an interpretive code translator, and to perform associated application studies.

Impact of task design on task performance and injury risk: case study of a simulated drilling task.

PubMed

Alabdulkarim, Saad; Nussbaum, Maury A; Rashedi, Ehsan; Kim, Sunwook; Agnew, Michael; Gardner, Richard

2017-06-01

Existing evidence is limited regarding the influence of task design on performance and ergonomic risk, or the association between these two outcomes. In a controlled experiment, we constructed a mock fuselage to simulate a drilling task common in aircraft manufacturing, and examined the effect of three levels of workstation adjustability on performance as measured by productivity (e.g. fuselage completion time) and quality (e.g. fuselage defective holes), and ergonomic risk as quantified using two common methods (rapid upper limb assessment and the strain index). The primary finding was that both productivity and quality significantly improved with increased adjustability, yet this occurred only when that adjustability succeeded in reducing ergonomic risk. Supporting the inverse association between ergonomic risk and performance, the condition with highest adjustability created the lowest ergonomic risk and the best performance while there was not a substantial difference in ergonomic risk between the other two conditions, in which performance was also comparable. Practitioner Summary: Findings of this study supported a causal relationship between task design and both ergonomic risk and performance, and that ergonomic risk and performance are inversely associated. While future work is needed under more realistic conditions and a broader population, these results may be useful for task (re)design and to help cost-justify some ergonomic interventions.

Soy intake is associated with lower lung cancer risk: results from a meta-analysis of epidemiologic studies123

PubMed Central

Yang, Wan-Shui; Va, Puthiery; Wong, Man-Yu; Zhang, Huan-Ling

2011-01-01

Background: Although several in vitro and animal in vivo studies have suggested that soy or soy isoflavones may exert inhibitory effects on lung carcinogenesis, epidemiologic studies have reported inconclusive results on the association between soy intake and lung cancer. Objective: The aim of this meta-analysis was to investigate whether an association exists between soy and lung cancer in epidemiologic studies. Design: We searched PubMed, EMBASE, and the Cochrane Library from their inception to February 2011 for both case-control and cohort studies that assessed soy consumption and lung cancer risk. Study-specific risk estimates were combined by using fixed-effect or random-effect models. Results: A total of 11 epidemiologic studies that consisted of 8 case-control and 3 prospective cohort studies were included. A significantly inverse association was shown between soy intake and lung cancer with an overall RR of 0.77 (95% CI: 0.65, 0.92). Findings were slightly different when analyses were restricted to 5 high-quality studies (RR: 0.70; 95% CI: 0.45, 0.99). In a subgroup meta-analysis, a statistically significant protective effect of soy consumption was observed in women (RR: 0.79; 95% CI: 0.67, 0.93), never smokers (RR: 0.62; 95% CI: 0.51, 0.76), and Asian populations (RR: 0.86; 95% CI: 0.74, 0.98). Conclusions: Our findings indicate that the consumption of soy food is associated with lower lung cancer risk. Because of different methods used to assess soy consumption across studies, more well-designed cohort studies or intervention studies that use unified measures of soy intake are needed to fully characterize such an association. PMID:22071712

Commentary: How can family-based quasi-experimental designs and national registers be used to address confounding in risk factor studies of psychopathology? A reflection on Obel et al. (2016).

PubMed

Larsson, Henrik

2016-04-01

Standard observational studies have reported a robust correlation between maternal smoking during pregnancy and risk of ADHD in offspring. In the accompanying article, Obel et al. used sibling-comparisons to explore the extent to which unmeasured familial confounding explains this association. This commentary highlights three important implications of the study. At a general level, Obel et al. illustrates how (1) family-based quasi-experimental designs and (2) national registers can be used to address confounding in risk factor studies of psychopathology. At a more specific level, the study suggests that maternal smoking during pregnancy is probably not a causal risk factor for ADHD. © 2016 Association for Child and Adolescent Mental Health.

Vaccine stability study design and analysis to support product licensure.

PubMed

Schofield, Timothy L

2009-11-01

Stability evaluation supporting vaccine licensure includes studies of bulk intermediates as well as final container product. Long-term and accelerated studies are performed to support shelf life and to determine release limits for the vaccine. Vaccine shelf life is best determined utilizing a formal statistical evaluation outlined in the ICH guidelines, while minimum release is calculated to help assure adequate potency through handling and storage of the vaccine. In addition to supporting release potency determination, accelerated stability studies may be used to support a strategy to recalculate product expiry after an unintended temperature excursion such as a cold storage unit failure or mishandling during transport. Appropriate statistical evaluation of vaccine stability data promotes strategic stability study design, in order to reduce the uncertainty associated with the determination of the degradation rate, and the associated risk to the customer.

Statistical Optimization of Pharmacogenomics Association Studies: Key Considerations from Study Design to Analysis

PubMed Central

Grady, Benjamin J.; Ritchie, Marylyn D.

2011-01-01

Research in human genetics and genetic epidemiology has grown significantly over the previous decade, particularly in the field of pharmacogenomics. Pharmacogenomics presents an opportunity for rapid translation of associated genetic polymorphisms into diagnostic measures or tests to guide therapy as part of a move towards personalized medicine. Expansion in genotyping technology has cleared the way for widespread use of whole-genome genotyping in the effort to identify novel biology and new genetic markers associated with pharmacokinetic and pharmacodynamic endpoints. With new technology and methodology regularly becoming available for use in genetic studies, a discussion on the application of such tools becomes necessary. In particular, quality control criteria have evolved with the use of GWAS as we have come to understand potential systematic errors which can be introduced into the data during genotyping. There have been several replicated pharmacogenomic associations, some of which have moved to the clinic to enact change in treatment decisions. These examples of translation illustrate the strength of evidence necessary to successfully and effectively translate a genetic discovery. In this review, the design of pharmacogenomic association studies is examined with the goal of optimizing the impact and utility of this research. Issues of ascertainment, genotyping, quality control, analysis and interpretation are considered. PMID:21887206

Racial discrimination and cortisol output: A meta-analysis.

PubMed

Korous, Kevin M; Causadias, José M; Casper, Deborah M

2017-11-01

Although the relation between stress and physiology is well documented, attempts at understanding the link between racial discrimination and cortisol output, specifically, have produced mixed results, likely due to study characteristics such as racial/ethnic composition of the samples (e.g., African American, Latino), measures of discrimination, and research design (e.g., cross-sectional, experimental). To estimate the overall association between racial discrimination and cortisol output among racial/ethnic minority individuals and to determine if the association between racial discrimination and cortisol output is moderated by age, race/ethnicity, type of discrimination measure, sex, and research design. Using a random effects model, the overall effect size based on k = 16 studies (19% unpublished) and N = 1506 participants was r¯ = 0.040, 95% CI = -0.038 to 0.117. Studies were conducted predominantly in the U.S. (81%). Notably, experimental studies (r¯ = 0.267) exhibited larger effect sizes compared to non-experimental studies (r¯ = -0.007). Age, race/ethnicity, type of discrimination measure, and sex did not moderate the effect sizes. This meta-analysis provides evidence that the measurement of the association between racial discrimination and cortisol is complex, and it offers valuable insight regarding methods and designs that can inform future research on this topic. Limitations and future directions are discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Correlates of comorbid depression, anxiety and helplessness with obsessive-compulsive disorder in Chinese adolescents.

PubMed

Sun, Jing; Li, Zhanjiang; Buys, Nicholas; Storch, Eric A

2015-03-15

Youth with obsessive-compulsive disorder (OCD) are at risk of experiencing comorbid psychiatric conditions, such as depression and anxiety. Studies of Chinese adolescents with OCD are limited. The aim of this study was to investigate the association of depression, anxiety, and helplessness with the occurrence of OCD in Chinese adolescents. This study consisted of two stages. The first stage used a cross-sectional design involving a stratified clustered non-clinical sample of 3174 secondary school students. A clinical interview procedure was then employed to diagnose OCD in students who had a Leyton 'yes' score of 15 or above. The second phase used a case-control study design to examine the relationship of OCD to depression, anxiety and helplessness in a matched sample of 288 adolescents with clinically diagnosed OCD and 246 students without OCD. Helplessness, depression and anxiety scores were directly associated with the probability of OCD caseness. Canonical correlation analysis indicated that the OCD correlated significantly with depression, anxiety, and helplessness. Cluster analysis further indicated that the degree of the OCD is also associated with severity of depression and anxiety, and the level of helplessness. These findings suggest that depression, anxiety and helplessness are important correlates of OCD in Chinese adolescents. Future studies using longitudinal and prospective designs are required to confirm these relationships as causal. Copyright © 2014 Elsevier B.V. All rights reserved.

The case-control design in veterinary sciences: A survey.

PubMed

Cullen, Jonah N; Sargeant, Jan M; Makielski, Kelly M; O'Connor, Annette M

2016-11-01

The case-control study design is deceptively simple. However, many design considerations influence the estimated effect measure. An investigation of case-control studies in the human health literature suggested that some of these considerations are not described in reports of case-control studies. Our hypothesis was that the majority of veterinary studies labeled as case-controls would be incident density designs, and many would not interpret the effect measure obtained from those studies as the rate ratio rather than the odds ratio. Reference databases were searched for author-designated case-control studies. A survey of 100 randomly selected studies was conducted to examine the different design options described and estimated effect measures. Of the 100 author-identified case-control studies, 83 assessed an exposure-outcome association and, of those, only 54 (65.1%) sampled the study population based on an outcome and would thus be considered case-control designs. Twelve studies were incidence density designs but none used this terminology. Of the studies that reported an odds ratio as the effect measure, none reported on additional considerations that would have enabled a more interpretable result. This survey indicated many case-control-labeled studies were not case-control designs and among case-control studies, key design aspects were not often described. The absence of information about study design elements and underlying assumptions in case-control studies limits the ability to establish the effect measured by the study and the evidentiary value of the study might be underestimated. Copyright © 2016 Elsevier B.V. All rights reserved.

Use of antiepileptic drugs and risk of falls in old age: A systematic review.

PubMed

Haasum, Ylva; Johnell, Kristina

2017-12-01

The aim of this study is to systematically review the scientific literature to investigate if use of antiepileptic drugs (AEDs) is associated with falls and/or recurrent falls in old age. We searched the literature for relevant articles in PubMed and Embase published up until 3rd December 2015. Studies on people aged 60 years and over with an observational design assessing the risk of fall in people exposed to AEDs compared to people not exposed to AED were included. We found 744 studies by searching Medline and Embase and an additional 9 studies by reviewing relevant reference lists. Of these studies, 13 fulfilled our predefined criteria. The articles were of various study design, sizes and follow-up times, and presented the results in different ways. Also, confounder adjustment varied considerably between the studies. Ten studies presented results for the association between use of any AED and any fall/injurious fall. Of these studies, 6 presented adjusted estimates, of which all but one showed statistically significant associations between use of any AED and any fall/injurious fall. Six studies investigated the association between use of any AED and recurrent falls. Of these, only 3 studies presented adjusted effect estimates of which 2 reached statistical significance for the association between use of AEDs and recurrent falls in elderly people. Our results indicate an association between use of AEDs and risk of falls and recurrent falls in older people. This finding may be clinically important given that a substantial amount of older people use these drugs. However, further research is needed to increase the knowledge about the actual risk of falls when using these drugs in old age. Copyright © 2017 Elsevier B.V. All rights reserved.

A survey sampling approach for pesticide monitoring of community water systems using groundwater as a drinking water source.

PubMed

Whitmore, Roy W; Chen, Wenlin

2013-12-04

The ability to infer human exposure to substances from drinking water using monitoring data helps determine and/or refine potential risks associated with drinking water consumption. We describe a survey sampling approach and its application to an atrazine groundwater monitoring study to adequately characterize upper exposure centiles and associated confidence intervals with predetermined precision. Study design and data analysis included sampling frame definition, sample stratification, sample size determination, allocation to strata, analysis weights, and weighted population estimates. Sampling frame encompassed 15 840 groundwater community water systems (CWS) in 21 states throughout the U. S. Median, and 95th percentile atrazine concentrations were 0.0022 and 0.024 ppb, respectively, for all CWS. Statistical estimates agreed with historical monitoring results, suggesting that the study design was adequate and robust. This methodology makes no assumptions regarding the occurrence distribution (e.g., lognormality); thus analyses based on the design-induced distribution provide the most robust basis for making inferences from the sample to target population.

Proceedings of the Conference on the Design of Experiments in Army Research Development and Testing (28th) Held at Monterey, California on 20-22 October 1982

DTIC Science & Technology

1983-06-01

program specifically designed to solve IME equations. The IME measure is a useful index because it translates system performance characteristics of...8.0 SUMMARY The purpose of this study was to design the field evaluation of a camou- flage system in such a manner that the camoufleur could...analysis of complex factorial designs and their associated systems of confounding ((44), [46)) and to the introduction of incomplete block designs . My

Getting Students Ready to Write: An Experiment in Online Teaching and Learning

ERIC Educational Resources Information Center

Poniatowski, Kelly

2012-01-01

A required writing mechanics course for mass communication students was moved online. A case study experiment manipulating the course design was conducted to determine effects on student engagement, learning, and satisfaction. Online designs with greater interactivity capabilities are positively associated with all three outcomes. These desirable…

Experiencing and Regulating Sadness: Physiological and Cognitive Effects

ERIC Educational Resources Information Center

Robinson, Jennifer L.; Demaree, Heath A.

2009-01-01

No prior study has examined the two most prominent response-focused regulation strategies (suppression and exaggeration) using a within-subjects design. Utilizing this design allows for a direct comparison of physiological patterns and cognitive impairment associated with such efforts. One hundred and nine participants were asked to view a series…

23 CFR 650.117 - Content of design studies.

Code of Federal Regulations, 2013 CFR

2013-04-01

... BRIDGES, STRUCTURES, AND HYDRAULICS Location and Hydraulic Design of Encroachments on Flood Plains § 650... probability of exceedance and, at appropriate locations, the water surface elevations associated with the overtopping flood or the flood of § 650.115(a)(1)(ii), and (2) The magnitude and water surface elevation of...

23 CFR 650.117 - Content of design studies.

Code of Federal Regulations, 2014 CFR

2014-04-01

... BRIDGES, STRUCTURES, AND HYDRAULICS Location and Hydraulic Design of Encroachments on Flood Plains § 650... probability of exceedance and, at appropriate locations, the water surface elevations associated with the overtopping flood or the flood of § 650.115(a)(1)(ii), and (2) The magnitude and water surface elevation of...

23 CFR 650.117 - Content of design studies.

Code of Federal Regulations, 2012 CFR

2012-04-01

... BRIDGES, STRUCTURES, AND HYDRAULICS Location and Hydraulic Design of Encroachments on Flood Plains § 650... probability of exceedance and, at appropriate locations, the water surface elevations associated with the overtopping flood or the flood of § 650.115(a)(1)(ii), and (2) The magnitude and water surface elevation of...

23 CFR 650.117 - Content of design studies.

Code of Federal Regulations, 2011 CFR

2011-04-01

... BRIDGES, STRUCTURES, AND HYDRAULICS Location and Hydraulic Design of Encroachments on Flood Plains § 650... probability of exceedance and, at appropriate locations, the water surface elevations associated with the overtopping flood or the flood of § 650.115(a)(1)(ii), and (2) The magnitude and water surface elevation of...

23 CFR 650.117 - Content of design studies.

Code of Federal Regulations, 2010 CFR

2010-04-01

... BRIDGES, STRUCTURES, AND HYDRAULICS Location and Hydraulic Design of Encroachments on Flood Plains § 650... probability of exceedance and, at appropriate locations, the water surface elevations associated with the overtopping flood or the flood of § 650.115(a)(1)(ii), and (2) The magnitude and water surface elevation of...

What are the defining characteristics of the most cited publications in orthognathic surgery?

PubMed

Susarla, S M; Tveit, M; Dodson, T B; Kaban, L B; Hopper, R A; Egbert, M A

2018-05-21

The purpose of this study was to identify the characteristics associated with highly cited papers in orthognathic surgery. This was a cohort study of articles published in the English-language literature from 1900 to 2017. Citation databases were searched for papers related to orthognathic surgery and the most frequently cited papers were identified. For each paper, the following variables were collected: region of origin, time-period of publication, corresponding author specialty, journal of publication, topic area, study design, and number of citations. The outcome variable was the citation index (citations per year). North American investigators published 70% of the 100 most-cited articles in orthognathic surgery. The majority of papers were from oral and maxillofacial surgeons. Frequent content areas were diagnosis, virtual planning, fixation/stability, and complications. The majority (54%) of studies were cohort or case report/series. The mean number of citations was 235.0±126.5; the mean citation index was 9.9±6.1 citations per year. Time-period, content area, and study design were associated with the citation index (all P<0.001). Time-period, content area, and study design predicted the citation index (all P≤0.009). Among frequently cited papers in orthognathic surgery, oral and maxillofacial surgeons had the highest volume of contributions. Diagnosis, treatment planning, and complications were the most common topics studied. Copyright © 2018 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Use of case-time-control design in pharmacovigilance applications: exploration with high-risk medications and unplanned hospital admissions in the Western Australian elderly.

PubMed

Price, Sylvie D; Holman, C D'Arcy J; Sanfilippo, Frank M; Emery, Jon D

2013-11-01

To use a case-time-control design to derive preliminary estimates of unplanned hospitalisations attributable to suspected high-risk medications in elderly Western Australians. Using pharmaceutical claims linked to inpatient and other health records, the study applied a case-time-control design and conditional logistic regression to estimate odds ratios (ORs) for unplanned hospital admissions associated with anticoagulants, antirheumatics, opioids, corticosteroids and four major groups of cardiovascular drugs. Attributable fractions (AFs) were derived from the ORs to estimate the number and proportion of admissions associated with drug exposure. Results were compared with those obtained from a more conventional method using International Classification of Diseases (ICD) external cause codes to identify admissions related to adverse drug events. The study involved 1 899 699 index hospital admissions. Six of the eight drug groups were associated with an increased risk of unplanned hospitalisation, opioids (adjusted OR = 1.81, 95%CI 1.75-1.88; AF = 44.9%) and corticosteroids (1.48, 1.42-1.54; 32.2%) linked with the highest risks. For all six, the estimated number of hospitalisations attributed to the medication in the exposed was higher (two to 31-fold) when derived from the case-time-control design compared with identification from ICD codes. This study provides an alternative approach for identifying potentially harmful medications and suggests that the use of ICD external causes may underestimate adverse drug events. It takes drug exposure into account, can be applied to individual medications and may overcome under-reporting issues associated with conventional methods. The approach shows great potential as part of a post-marketing pharmacovigilance monitoring system in Australia and elsewhere. Copyright © 2013 John Wiley & Sons, Ltd.

Utilising family-based designs for detecting rare variant disease associations.

PubMed

Preston, Mark D; Dudbridge, Frank

2014-03-01

Rare genetic variants are thought to be important components in the causality of many diseases but discovering these associations is challenging. We demonstrate how best to use family-based designs to improve the power to detect rare variant disease associations. We show that using genetic data from enriched families (those pedigrees with greater than one affected member) increases the power and sensitivity of existing case-control rare variant tests. However, we show that transmission- (or within-family-) based tests do not benefit from this enrichment. This means that, in studies where a limited amount of genotyping is available, choosing a single case from each of many pedigrees has greater power than selecting multiple cases from fewer pedigrees. Finally, we show how a pseudo-case-control design allows a greater range of statistical tests to be applied to family data. © 2014 The Authors. Annals of Human Genetics published by John Wiley & Sons Ltd/University College London.

Breast milk and cognitive development—the role of confounders: a systematic review

PubMed Central

Walfisch, Asnat; Sermer, Corey; Cressman, Alex; Koren, Gideon

2013-01-01

Objectives The association between breastfeeding and child cognitive development is conflicted by studies reporting positive and null effects. This relationship may be confounded by factors associated with breastfeeding, specifically maternal socioeconomic class and IQ. Design Systematic review of the literature. Setting and participants Any prospective or retrospective study, in any language, evaluating the association between breastfeeding and cognitive development using a validated method in healthy term infants, children or adults, was included. Primary and secondary outcome measures Extracted data included the study design, target population and sample size, breastfeeding exposure, cognitive development assessment tool used and participants’ age, summary of the results prior to, and following, adjustment for confounders, and all confounders adjusted for. Study quality was assessed as well. Results 84 studies met our inclusion criteria (34 rated as high quality, 26 moderate and 24 low quality). Critical assessment of accepted studies revealed the following associations: 21 null, 28 positive, 18 null after adjusting for confounders and 17 positive—diminished after adjusting for confounders. Directionality of effect did not correlate with study quality; however, studies showing a decreased effect after multivariate analysis were of superior quality compared with other study groupings (14/17 high quality, 82%). Further, studies that showed null or diminished effect after multivariate analysis corrected for significantly more confounders (7.7±3.4) as compared with those that found no change following adjustment (5.6±4.5, p=0.04). The majority of included studies were carried out during childhood (75%) and set in high-income countries (85.5%). Conclusions Much of the reported effect of breastfeeding on child neurodevelopment is due to confounding. It is unlikely that additional work will change the current synthesis. Future studies should attempt to rigorously control for all important confounders. Alternatively, study designs using sibling cohorts discordant for breastfeeding may yield more robust conclusions. PMID:23975102

Biological and Rearing Mother Influences on Child ADHD Symptoms: Revisiting the Developmental Interface between Nature and Nurture

PubMed Central

Harold, Gordon T.; Leve, Leslie D.; Barrett, Douglas; Elam, Kit; Neiderhiser, Jenae M.; Natsuaki, Misaki N.; Shaw, Daniel S.; Reiss, David; Thapar, Anita

2013-01-01

Background Families of children with attention deficit hyperactivity disorder (ADHD) report more negative family relationships than families of children without ADHD. Questions remain as to the role of genetic factors underlying associations between family relationships and children’s ADHD symptoms, and the role of children’s ADHD symptoms as an evocative influence on the quality of relationships experienced within such families. Utilizing the attributes of two genetically sensitive research designs, the present study examined associations between biologically related and non-biologically related maternal ADHD symptoms, parenting practices, child impulsivity/activation, and child ADHD symptoms. The combined attributes of the study designs permit assessment of associations while controlling for passive genotype-environment correlation and directly examining evocative genotype-environment correlation (rGE); two relatively under examined confounds of past research in this area. Methods A cross-sectional adoption-at-conception design (Cardiff IVF Study; C-IVF) and a longitudinal adoption-at-birth design (Early Growth and Development Study; EGDS) were used. The C-IVF sample included 160 mothers and children (age 5–8 years). The EGDS sample included 320 linked sets of adopted children (age 6 years), adoptive-, and biologically-related mothers. Questionnaires were used to assess maternal ADHD symptoms, parenting practices, child impulsivity/activation, and child ADHD symptoms. A cross-rater approach was used across measures of maternal behavior (mother reports) and child ADHD symptoms (father reports). Results Significant associations were revealed between rearing mother ADHD symptoms, hostile parenting behavior, and child ADHD symptoms in both samples. Because both samples consisted of genetically-unrelated mothers and children, passive rGE was removed as a possible explanatory factor underlying these associations. Further, path analysis revealed evidence for evocative rGE processes in the longitudinal adoption-at-birth study (EGDS) from biologically-related maternal ADHD symptoms to biologically-unrelated maternal hostile parenting through early disrupted child behavior (impulsivity/activation), with maternal hostile parenting and disrupted child behavior associated with later child ADHD symptoms, controlling for concurrent adoptive mother ADHD symptoms. Conclusions Results highlight the importance of genetically-influenced child ADHD-related temperamental attributes on genetically-unrelated maternal hostility that in turn links to later child ADHD symptoms. Implications for intervention programs focusing on early family processes and the precursors of child ADHD symptoms are discussed. PMID:24007415

The Power of Fully Supporting Community College Students: The Effects of The City University of New York's Accelerated Study in Associate Programs after Six Years

ERIC Educational Resources Information Center

Gupta, Himani

2017-01-01

The Accelerated Study in Associate Programs (ASAP), developed by the City University of New York (CUNY), is an uncommonly comprehensive and long-term program designed to address low graduation rates among community college students. MDRC has been studying the effects of ASAP on low-income students with developmental (remedial) education needs at…

Study of process variables associated with manufacturing hermetically-sealed nickel-cadmium cells

NASA Technical Reports Server (NTRS)

Miller, L.; Doan, D. J.; Carr, E. S.

1971-01-01

A program to determine and study the critical process variables associated with the manufacture of aerospace, hermetically-sealed, nickel-cadmium cells is described. The determination and study of the process variables associated with the positive and negative plaque impregnation/polarization process are emphasized. The experimental data resulting from the implementation of fractional factorial design experiments are analyzed by means of a linear multiple regression analysis technique. This analysis permits the selection of preferred levels for certain process variables to achieve desirable impregnated plaque characteristics.

Interior Landscape Plants for Indoor Air Pollution Abatement

NASA Technical Reports Server (NTRS)

Wolverton, B. C.; Johnson, Anne; Bounds, Keith

1989-01-01

In this study, the leaves, roots, soil, and associated microorganisms of plants have been evaluated as a possible means of reducing indoor air pollutants. Additionally, a novel approach of using plant systems for removing high concentrations of indoor air pollutants such as cigarette smoke, organic solvents, and possibly radon has been designed from this work. This air filter design combines plants with an activated carbon filter. The rationale for this design, which evolved from wastewater treatment studies, is based on moving large volumes of contaminated air through an activated carbon bed where smoke, organic chemicals, pathogenic microorganisms (if present), and possibly radon are absorbed by the carbon filter. Plant roots and their associated microorganisms then destroy the pathogenic viruses, bacteria, and the organic chemicals, eventually converting all of these air pollutants into new plant tissue. It is believed that the decayed radon products would be taken up the plant roots and retained in the plant tissue.

GLobal Integrated Design Environment (GLIDE): A Concurrent Engineering Application

NASA Technical Reports Server (NTRS)

McGuire, Melissa L.; Kunkel, Matthew R.; Smith, David A.

2010-01-01

The GLobal Integrated Design Environment (GLIDE) is a client-server software application purpose-built to mitigate issues associated with real time data sharing in concurrent engineering environments and to facilitate discipline-to-discipline interaction between multiple engineers and researchers. GLIDE is implemented in multiple programming languages utilizing standardized web protocols to enable secure parameter data sharing between engineers and researchers across the Internet in closed and/or widely distributed working environments. A well defined, HyperText Transfer Protocol (HTTP) based Application Programming Interface (API) to the GLIDE client/server environment enables users to interact with GLIDE, and each other, within common and familiar tools. One such common tool, Microsoft Excel (Microsoft Corporation), paired with its add-in API for GLIDE, is discussed in this paper. The top-level examples given demonstrate how this interface improves the efficiency of the design process of a concurrent engineering study while reducing potential errors associated with manually sharing information between study participants.

The Effects of Moderate- and High-Fidelity Patient Simulator Use on Critical Thinking in Associate Degree Nursing Students

ERIC Educational Resources Information Center

Vieck, Jana

2013-01-01

The purpose of this study was to examine the impact of moderate- and high-fidelity patient simulator use on the critical thinking skills of associate degree nursing students. This quantitative study used a quasi-experimental design and the Health Sciences Reasoning Test (HSRT) to evaluate the critical thinking skills of third semester nursing…

The Association of Age, Sense of Control, Optimism, and Self-Esteem with Emotional Distress

ERIC Educational Resources Information Center

Jiménez, M. Guadalupe; Montorio, Ignacio; Izal, María

2017-01-01

The aim of this study was to test a model of emotional distress, which incorporates the potential mediator role of positive resources (sense of control, self-esteem, and optimism) in the association of age with emotional distress. The study used a cross-sectional design with intentional sampling and the voluntary participation of 325 adults…

The Role of DNA Methylation in Cardiovascular Risk and Disease: Methodological Aspects, Study Design, and Data Analysis for Epidemiological Studies.

PubMed

Zhong, Jia; Agha, Golareh; Baccarelli, Andrea A

2016-01-08

Epidemiological studies have demonstrated that genetic, environmental, behavioral, and clinical factors contribute to cardiovascular disease development. How these risk factors interact at the cellular level to cause cardiovascular disease is not well known. Epigenetic epidemiology enables researchers to explore critical links between genomic coding, modifiable exposures, and manifestation of disease phenotype. One epigenetic link, DNA methylation, is potentially an important mechanism underlying these associations. In the past decade, there has been a significant increase in the number of epidemiological studies investigating cardiovascular risk factors and outcomes in relation to DNA methylation, but many gaps remain in our understanding of the underlying cause and biological implications. In this review, we provide a brief overview of the biology and mechanisms of DNA methylation and its role in cardiovascular disease. In addition, we summarize the current evidence base in epigenetic epidemiology studies relevant to cardiovascular health and disease and discuss the limitations, challenges, and future directions of the field. Finally, we provide guidelines for well-designed epigenetic epidemiology studies, with particular focus on methodological aspects, study design, and analytical challenges. © 2016 American Heart Association, Inc.

Solar thermoelectric generators

NASA Technical Reports Server (NTRS)

1977-01-01

The methods, the findings and the conclusions of a study for the design of a Solar Thermoelectric Generator (STG) intended for use as a power source for a spacecraft orbiting the planet Mercury are discussed. Several state-of-the-art thermoelectric technologies in the intended application were considered. The design of various STG configurations based on the thermoelectric technology selected from among the various technologies was examined in detail and a recommended STG design was derived. The performance characteristics of the selected STG technology and associated design were studied in detail as a function of the orbital characteristics of the STG in Mercury and throughout the orbit of Mercury around the sun.

Research Review: Psychosocial adjustment and mental health in former child soldiers – a systematic review of the literature and recommendations for future research

PubMed Central

Betancourt, Theresa S.; Borisova, Ivelina; Williams, Timothy P.; Meyers-Ohki, Sarah E.; Rubin-Smith, Julia E.; Annan, Jeannie; Kohrt, Brandon A.

2014-01-01

Aims and scope This article reviews the available quantitative research on psychosocial adjustment and mental health among children (age <18 years) associated with armed forces and armed groups (CAAFAG) – commonly referred to as child soldiers. Methods PRISMA standards for systematic reviews were used to search PubMed, PsycInfo, JSTOR, and Sociological Abstracts in February 2012 for all articles on former child soldiers and CAAFAG. Twenty-one quantitative studies from 10 countries were analyzed for author, year of publication, journal, objectives, design, selection population, setting, instruments, prevalence estimates, and associations with war experiences. Opinion pieces, editorials, and qualitative studies were deemed beyond the scope of this study. Quality of evidence was rated according to the Systematic Assessment of Quality in Observational Research (SAQOR). Findings According to SAQOR criteria, among the available published studies, eight studies were of high quality, four were of moderate quality, and the remaining nine were of low quality. Common limitations were lack of validated mental health measures, unclear methodology including undefined sampling approaches, and failure to report missing data. Only five studies included a comparison group of youth not involved with armed forces/armed groups, and only five studies assessed mental health at more than one point in time. Across studies, a number of risk and protective factors were associated with postconflict psychosocial adjustment and social reintegration in CAAFAG. Abduction, age of conscription, exposure to violence, gender, and community stigma were associated with increased internalizing and externalizing mental health problems. Family acceptance, social support, and educational/economic opportunities were associated with improved psychosocial adjustment. Conclusions Research on the social reintegration and psychosocial adjustment of former child soldiers is nascent. A number of gaps in the available literature warrant future study. Recommendations to bolster the evidence base on psychosocial adjustment in former child soldiers and other war-affected youth include more studies comprising longitudinal study designs, and validated cross-cultural instruments for assessing mental health, as well as more integrated community-based approaches to study design and research monitoring. PMID:23061830

The association of age, sense of control, optimism, and self-esteem with emotional distress.

PubMed

Jiménez, M Guadalupe; Montorio, Ignacio; Izal, María

2017-07-01

The aim of this study was to test a model of emotional distress, which incorporates the potential mediator role of positive resources (sense of control, self-esteem, and optimism) in the association of age with emotional distress. The study used a cross-sectional design with intentional sampling and the voluntary participation of 325 adults between 18 and 87 years (M = 46.8 ± 19.10). The results show that emotional distress was negatively associated with age. Psychological resources also varied according to age, with older subjects presenting higher optimism and external control as well as lower internal control. The association between internal control and emotional distress was mediated by optimism and self-esteem. Moreover, the combined association of these 3 personal resources significantly increased the relationship between age and lower emotional distress. The results suggest that optimism and self-esteem are powerful resources in relieving emotional distress. The data provide potentially useful information for the design of psychological interventions aimed at reducing emotional distress. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Study designs, use of statistical tests, and statistical analysis software choice in 2015: Results from two Pakistani monthly Medline indexed journals.

PubMed

Shaikh, Masood Ali

2017-09-01

Assessment of research articles in terms of study designs used, statistical tests applied and the use of statistical analysis programmes help determine research activity profile and trends in the country. In this descriptive study, all original articles published by Journal of Pakistan Medical Association (JPMA) and Journal of the College of Physicians and Surgeons Pakistan (JCPSP), in the year 2015 were reviewed in terms of study designs used, application of statistical tests, and the use of statistical analysis programmes. JPMA and JCPSP published 192 and 128 original articles, respectively, in the year 2015. Results of this study indicate that cross-sectional study design, bivariate inferential statistical analysis entailing comparison between two variables/groups, and use of statistical software programme SPSS to be the most common study design, inferential statistical analysis, and statistical analysis software programmes, respectively. These results echo previously published assessment of these two journals for the year 2014.

Association of Proteinuria with Race, Cause of Chronic Kidney Disease, and Glomerular Filtration Rate in the Chronic Kidney Disease in Children Study

PubMed Central

Wong, Craig S.; Pierce, Christopher B.; Cole, Stephen R.; Warady, Bradley A.; Mak, Robert H.K.; Benador, Nadine M.; Kaskel, Fredrick; Furth, Susan L.; Schwartz, George J.

2009-01-01

Background and objectives: Proteinuria is associated with chronic kidney disease (CKD), and heavy proteinuria predicts a rapid decline in kidney function. However, the epidemiologic distribution of this important biomarker study is not well described in the pediatric CKD population. Design, setting, participants & measurements: This cross-sectional study of North American children with CKD examined the association of proteinuria among the baseline clinical variables in the cohort. Urinary protein-to-creatinine ratios (Up/c) were used to measure level of proteinuria. Results: Of the 419 subjects studied, the median GFR as measured by iohexol disappearance (iGFR) was 42 ml/min per 1.73 m2, median duration of CKD was six yr, and glomerular diseases accounted for 22% of the CKD diagnoses. Twenty-four percent of children had normal range (Up/c <0.2), 62% had significant, and 14% had nephrotic-range proteinuria (Up/c >2.0). A decrease in iGFR was associated with an increase in Up/c. At any level of GFR, a higher Up/c was associated with a glomerular cause of CKD and non-Caucasian race. Among subjects with a glomerular cause of CKD, Up/c was lower in subjects reporting utilization of renin-angiotensin system (RAS) antagonists (median Up/c = 0.93) compared with those who did not (median Up/c = 3.78). Conclusions: Proteinuria is associated with level of iGFR, cause of CKD, and race. The longitudinal study design of Chronic Kidney Disease in Children (CKiD) cohort study and the large number of subjects being studied has created an opportunity to better define the association between proteinuria and CKD progression. PMID:19297612

Association Between Whole-Body Vibration and Low-Back Disorders in Farmers: A Scoping Review.

PubMed

Kwaku Essien, Samuel; Trask, Catherine; Khan, Muhammad; Boden, Catherine; Bath, Brenna

2018-01-01

Low-back disorders (LBDs) are the most common musculoskeletal problem among farmers, with higher prevalence rates than in other occupations. Farmers who operate tractors and other types of machinery can have substantial exposure to whole-body vibration (WBV). Although there appears to be an association between LBDs and WBV, the causal relationship is not clear. This scoping review investigates the association between WBV and LBDs specifically among farmers. Nine databases were searched using groups of terms for two concepts: 'farming' and 'low back disorder'. Screening, data extraction, and quality assessment were performed by two reviewers independently. Included studies met the following criteria: focused on adult farmers/agricultural workers; assessed exposure to operating farm machinery such tractor, combine, or all-terrain vehicle; assessed LBDs as an outcome; and reported an inferential test to assess the relationship between WBV and LBD. After 276 full texts screened, 11 articles were found to analyze WBV as a risk factor for LBDs. Three were case-control, five cross-sectional, and three retrospective cohorts. Four studies showed no association between WBV and LBDs, four a positive association, and three results were mixed depending on the exposure/outcome measure. A firm conclusion is difficult due to heterogeneity in, LBDs definition, type of farm commodity, study design, and statistical strategy. Direct comparisons and synthesis were not possible. Although retrospective cohort studies tended to show a relationship, future studies with a prospective cohort design could help clarify this association further.

Statins and Risk of Lower Limb Revision Surgery: The Influence of Differences in Study Design Using Electronic Health Records From the United Kingdom and Denmark

PubMed Central

Lalmohamed, Arief; van Staa, Tjeerd P.; Vestergaard, Peter; Leufkens, Hubertus G. M.; de Boer, Anthonius; Emans, Pieter; Cooper, Cyrus; de Vries, Frank

2016-01-01

Abstract Previous observational studies on statins have shown variable results based on the methodology used. Our objective was to study the association between statins and orthopedic implant failure and to explore the influence of methodological differences in study design. Our study base consisted of patients with a primary total joint replacement in Denmark and the United Kingdom (n = 189,286; 1987–2012). We used 4 study designs: 1) case-control (each patient with revision surgery matched to 4 controls), 2) time-dependent cohort (postoperative statin use as a time-varying exposure variable), 3) immortal time cohort (misclassifying the time postoperatively before statin use), and 4) time-exclusion cohort (excluding the time postoperatively before statin use). Cox proportional hazards models and logistic regression were used to estimate incidence rate ratios. In the time-dependent cohort design, statin use was associated with a decreased risk of revision surgery (adjusted incidence rate ratio (IRR) = 0.90, 95% confidence interval (CI): 0.85, 0.96), which was similar to our case-control results (IRR = 0.87, 95% CI: 0.81, 0.93). In contrast, both time-fixed cohort designs yielded substantially lower risk estimates (IRR = 0.36 (95% CI: 0.34, 0.38) and IRR = 0.65 (95% CI: 0.63, 0.68), respectively). We discourage the use of time-fixed cohort studies, which may falsely suggest protective effects. The simple choice of how to classify exposure can substantially change results from biologically plausible to implausible. PMID:27317693

Understanding the Relationship between Activity and Neighbourhoods (URBAN) Study: research design and methodology

PubMed Central

Badland, Hannah M; Schofield, Grant M; Witten, Karen; Schluter, Philip J; Mavoa, Suzanne; Kearns, Robin A; Hinckson, Erica A; Oliver, Melody; Kaiwai, Hector; Jensen, Victoria G; Ergler, Christina; McGrath, Leslie; McPhee, Julia

2009-01-01

Background Built environment attributes are recognized as being important contributors to physical activity (PA) engagement and body size in adults and children. However, much of the existing research in this emergent public health field is hindered by methodological limitations, including: population and site homogeneity, reliance on self-report measures, aggregated measures of PA, and inadequate statistical modeling. As an integral component of multi-country collaborative research, the Understanding the Relationship between Activity and Neighbourhoods (URBAN) Study seeks to overcome these limitations by determining the strengths of association between detailed measures of the neighborhood built environment with PA levels across multiple domains and body size measures in adults and children. This article outlines the research protocol developed for the URBAN Study. Methods and design The URBAN Study is a multi-centered, stratified, cross-sectional research design, collecting data across four New Zealand cities. Within each city, 12 neighborhoods were identified and selected for investigation based on higher or lower walkability and Māori demographic attributes. Neighborhoods were selected to ensure equal representation of these characteristics. Within each selected neighborhood, 42 households are being randomly selected and an adult and child (where possible) recruited into the study. Data collection includes: objective and self-reported PA engagement, neighborhood perceptions, demographics, and body size measures. The study was designed to recruit approximately 2,000 adults and 250 children into the project. Other aspects of the study include photovoice, which is a qualitative assessment of built environment features associated with PA engagement, an audit of the neighborhood streetscape environment, and an individualized neighborhood walkability profile centered on each participant's residential address. Multilevel modeling will be used to examine the individual-level and neighborhood-level relationships with PA engagement and body size. Discussion The URBAN Study is applying a novel scientifically robust research design to provide urgently needed epidemiological information regarding the associations between the built environment and health outcomes. The findings will contribute to a larger, international initiative in which similar neighborhood selection and PA measurement procedures are utilized across eight countries. Accordingly, this study directly addresses the international priority issues of increasing PA engagement and decreasing obesity levels. PMID:19589175

The Solar Probe mission - Mission design concepts and requirements

NASA Technical Reports Server (NTRS)

Ayon, Juan A.

1992-01-01

The Solar Probe concept as studied by the Jet Propulsion Laboratory represents the first mission to combine out-of-the-ecliptic scientific coverage with multiple, close solar encounters (at 4 solar radii). The scientific objectives of the mission have driven the investigation and analysis of several mission design concepts, all optimized to meet the science/mission requirements. This paper reviews those mission design concepts developed, the science objectives that drive the mission design, and the principle mission requirements associated with these various concepts.

Microwave monolithic integrated circuit development for future spaceborne phased array antennas

NASA Astrophysics Data System (ADS)

Anzic, G.; Kascak, T. J.; Downey, A. N.; Liu, D. C.; Connolly, D. J.

The development of fully monolithic gallium arsenide (GaAs) receive and transmit modules suitable for phased array antenna applications in the 30/20 gigahertz bands is presented. Specifications and various design approaches to achieve the design goals are described. Initial design and performance of submodules and associated active and passive components are presented. A tradeoff study summary is presented, highlighting the advantages of a distributed amplifier approach compared to the conventional single power source designs. Previously announced in STAR as N84-13399

Microwave monolithic integrated circuit development for future spaceborne phased array antennas

NASA Technical Reports Server (NTRS)

Anzic, G.; Kascak, T. J.; Downey, A. N.; Liu, D. C.; Connolly, D. J.

1984-01-01

The development of fully monolithic gallium arsenide (GaAs) receive and transmit modules suitable for phased array antenna applications in the 30/20 gigahertz bands is presented. Specifications and various design approaches to achieve the design goals are described. Initial design and performance of submodules and associated active and passive components are presented. A tradeoff study summary is presented, highlighting the advantages of a distributed amplifier approach compared to the conventional single power source designs. Previously announced in STAR as N84-13399

Association Between Periodontal Disease and Erectile Dysfunction: A Systematic Review.

PubMed

Kellesarian, Sergio Varela; Kellesarian, Tammy Varela; Ros Malignaggi, Vanessa; Al-Askar, Mansour; Ghanem, Alexis; Malmstrom, Hans; Javed, Fawad

2018-03-01

A limited number of studies have reported an association between erectile dysfunction (ED) and chronic periodontitis (CP). The aim of the present study is to assess the association between CP and ED through a systematic review of published literature. To address the focused question, "Is there a relationship between ED and CP?" indexed databases were searched till December 2015 using various key words "erectile dysfunction," "periodontal disease," "periodontitis," "dental infection," and "impotence." Letters to the editor, commentaries, historic reviews, and experimental studies were excluded. The pattern of the present systematic review was customized to primarily summarize the pertinent data. Nine studies were included. Seven studies had a cross-sectional design and two studies were randomized control trials. The number of study participants ranged between 53 and 513,258 individuals with age ranging between 20 years and 85 years (median age ranging between 34.9 ± 4.9 years and 50.9 ± 16.6 years). In all studies, a positive relationship between CP and ED was reported. In four studies, odds ratio were reported, ranging between 1.53 and 3.35. From the literature reviewed, there seems to be a positive association between ED and CP; however, further well-designed controlled clinical trials are needed in this regard. It is emphasized that physicians should refer patients with ED to oral health care providers for a comprehensive oral evaluation and treatment.

Glutathione-S-transferase polymorphisms (GSTM1, GSTT1 and GSTP1) and acute leukemia risk in Asians: a meta-analysis.

PubMed

Tang, Zhen-Hai; Zhang, Chi; Cheng, Pan; Sun, Hong-Min; Jin, Yu; Chen, Yuan-Jing; Huang, Fen

2014-01-01

The association between glutathione-S-transferase polymorphisms (GSTM1, GSTT1 and GSTP1) and risk of acute leukemia in Asians remains controversial. This study was therefore designed to evaluate the precise association in 23 studies identified by a search of PubMed and several other databases, up to December 2013. Using random or fixed effects models odds ratios (ORs) with corresponding 95% confidence intervals (CIs) were calculated. Heterogeneity across studies was assessed, and funnel plots were constructed to test for publication bias. The meta-analysis showed positive associations between GST polymorphisms (GSTM1 and GSTT1 but not GSTP1) and acute leukemia risk [(OR=1.47, 95% CI 1.18-1.83); (OR=1.32, 95% CI 1.07-1.62); (OR=1.01, 95% CI 0.84-1.23), respectively] and heterogeneity between the studies. The results suggested that the GSTM1 null genotype and GSTT1null genotype, but not the GSTP1 polymorphism, might be a potential risk factors for acute leukemia. Further well-designed studies are needed to confirm our findings.

Ergonomic nursing workstation design to prevent cumulative trauma disorders.

PubMed

McHugh, M L; Schaller, P

1997-01-01

The introduction of computerized nursing information systems offers health care institutions an opportunity to take a new look at safety issues related to nursing workstation design. Industrial studies have investigated the injuries sustained by clerical workers who spend long periods of time at their computers. Cumulative trauma disorders (CTDs) are the most common injuries associated with computerized workstation use. They account for nearly 90,000 injuries each year in the United States. Typical CTDs include back pain, strain of the neck, shoulders and eyes, and carpal tunnel syndrome. As the information handling work of nurses is increasingly computerized, the incidence of computer-related injury is expected to increase. Injury rates can be reduced by ergonomic workstation design. An assessment of potential risks associated with the equipment installed should be done as part of workstation design. Risk identification is a prerequisite for avoiding injuries by designing workstations that protect human health. The ergonomic principles learned and tested on office workers are addressed and extrapolated to nursing workstation design. Specific suggestions for design of sitting and standing workstations are presented.

Systematic review of self-reported cognitive function in cancer patients following chemotherapy treatment.

PubMed

Bray, Victoria J; Dhillon, Haryana M; Vardy, Janette L

2018-05-04

Cognitive symptoms are common in cancer patients, with up to 70% reporting cognitive symptoms following chemotherapy. These symptoms can have a major impact on how an individual functions in all aspects of their lives. This review evaluates self-reported cognitive function and its associations with neuropsychological tests and patient-reported outcomes in adult cancer patients who received chemotherapy treatment for a solid cancer. A search of multiple databases (Medline, Ovid at Nursing, PsycINFO, Allied and Complementary Medicine) from 1936 to 2017 was conducted, identifying 1563 unique articles, of which 101 met inclusion criteria. Of the 101 included studies, 48 (47%) were cross-sectional and 38 (38%) longitudinal in design, with 12 (12%) randomised controlled trials. A minority (26%) incorporated a healthy control arm in the study design, whilst the majority (79%) were in women with breast cancer. There was diversity in the assessment of self-reported cognitive symptoms. A total of 43 of 44 studies that sought an association between self-reported cognitive function and patient-reported outcomes found a moderate to strong association. Overall, 31 studies showed a lack of association between self-reported cognitive symptoms and neuropsychological results, whilst 14 studies reported a significant association between the two, but the association was often restricted to limited cognitive domains. The review found widespread heterogeneity in the assessment of self-reported cognitive symptoms and consistently absent or weak association with neuropsychological test scores. This research highlights the need for a standardised approach to measurement of self-reported cognitive symptoms in cancer patients.

Dietary guideline adherence index and kidney measures in the framingham heart study

USDA-ARS?s Scientific Manuscript database

BACKGROUND: No observational studies have directly considered dietary guidelines when examining the prospective association between dietary intake and kidney measures. STUDY DESIGN: Prospective cohort study. SETTING & PARTICIPANTS: We examined participants who attended examinations 7 (1998-2001) a...

Design definition study of a NASA/Navy lift/cruise fan technology V/STOL airplane: Risk assessment addendum to the final report

NASA Technical Reports Server (NTRS)

Zabinsky, J. M.; Burnham, R. W.; Flora, C. C.; Gotlieb, P.; Grande, D. L.; Gunnarson, D. W.; Howard, W. M.; Hunt, D.; Jakubowski, G. W.; Johnson, P. E.

1975-01-01

An assessment of risk, in terms of delivery delays, cost overrun, and performance achievement, associated with the V/STOL technology airplane is presented. The risk is discussed in terms of weight, structure, aerodynamics, propulsion, mechanical drive, and flight controls. The analysis ensures that risks associated with the design and development of the airplane will be eliminated in the course of the program and a useful technology airplane that meets the predicted cost, schedule, and performance can be produced.

Cooperativity and specificity of association of a designed transmembrane peptide.

PubMed Central

Gratkowski, Holly; Dai, Qing-Hong; Wand, A Joshua; DeGrado, William F; Lear, James D

2002-01-01

Thermodynamics studies aimed at quantitatively characterizing free energy effects of amino acid substitutions are not restricted to two state systems, but do require knowing the number of states involved in the equilibrium under consideration. Using analytical ultracentrifugation and NMR methods, we show here that a membrane-soluble peptide, MS1, designed by modifying the sequence of the water-soluble coiled-coil GCN4-P1, exhibits a reversible monomer-dimer-trimer association in detergent micelles with a greater degree of cooperativity in C14-betaine than in dodecyl phosphocholine detergents. PMID:12202385

Ergonomics for the inclusion of older workers in the knowledge workforce and a guidance tool for designers.

PubMed

Gonzalez, I; Morer, P

2016-03-01

The ageing of the population and the inverted population pyramid is bringing important changes to society as a whole. These changes are associated with the inclusion of an older workforce in knowledge work and the challenge they represent in adapting the work environment accordingly. In order to approach a more universal design of the work environment, industrial designers need support from user-sensitive inclusive design studies. While there are plenty of guidelines and tools containing relevant information, there is a need to develop more appropriate tools for Industrial Designers that cover the initial phase of the design process. This study provides a review of the available tools and guidelines and proposes a theoretical framework intended for developing a design guidance tool for inclusive workstation design. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Exploring factors and caregiver outcomes associated with feelings of preparedness for caregiving in family caregivers in palliative care: a correlational, cross-sectional study.

PubMed

Henriksson, Anette; Årestedt, Kristofer

2013-07-01

Family caregivers in palliative care often report feeling insufficiently prepared to handle the caregiver role. Preparedness has been confirmed as a variable that may actually protect family caregiver well-being. Preparedness refers to how ready family caregivers perceive they are for the tasks and demands in the caregiving role. The aim of this study was to explore factors associated with preparedness and to further investigate whether preparedness is associated with caregiver outcomes. This was a correlational study using a cross-sectional design. The study took place in three specialist palliative care units and one haematology unit. A total of 125 family caregivers of patients with life-threatening illness participated. Preparedness was significantly associated with higher levels of hope and reward and with a lower level of anxiety. In contrast, preparedness was not associated with depression or health. Being female and cohabiting with the patient were significantly associated with a higher level of preparedness. The relationship to the patient was significantly associated with preparedness, while social support, place of care, time since diagnosis and age of the patients showed no association. Feelings of preparedness seem to be important for how family caregivers experience the unique situation when caring for a patient who is severely ill and close to death. Our findings support the inclusion of preparedness in support models for family caregivers in palliative care. Psycho-educational interventions could preferably be designed aiming to increase family caregiver's preparedness to care, including practical care, communication and emotional support.

Design and Rationale of the Intima-Medial Thickness Sub-Study of the PreventIon of CArdiovascular Events in iSchemic Stroke Patients with High Risk of Cerebral hemOrrhage (PICASSO-IMT) Study.

PubMed

Seo, Woo-Keun; Kim, Yong Jae; Lee, Juneyoung; Kwon, Sun U

2017-09-01

Atherosclerosis is one of the main mechanisms of stroke and cardiovascular diseases and is associated with increased risk of recurrent stroke and cardiovascular events. Intima-medial thickness (IMT) is a well-known surrogate marker of atherosclerosis and has been used to predict stroke and cardiovascular events. However, the clinical significance of IMT and IMT change in stroke has not been investigated in well-designed studies. The PreventIon of CArdiovascular events in iSchemic Stroke patients with high risk of cerebral hemOrrhage-Intima-Media Thickness (PICASSO-IMT) sub-study is designed to investigate the effects of cilostazol, probucol, or both on IMT in patients with stroke. PICASSO-IMT is a prospective sub-study of the PICASSO study designed to measure IMT and plaque score at 1, 13, 25, 37, and 49 months after randomization. The primary outcome is the change in mean carotid IMT, which is defined as the mean of the far-wall IMTs of the right and left common carotid arteries, between baseline and 13 months after randomization. PICASSO-IMT will provide the largest IMT data set in a stroke population and will provide valuable information about the clinical significance of IMT in patients with ischemic stroke. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Structural cost optimization of photovoltaic central power station modules and support structure

NASA Technical Reports Server (NTRS)

Sutton, P. D.; Stolte, W. J.; Marsh, R. O.

1979-01-01

The results of a comprehensive study of photovoltaic module structural support concepts for photovoltaic central power stations and their associated costs are presented. The objective of the study has been the identification of structural cost drivers. Parametric structural design and cost analyses of complete array systems consisting of modules, primary support structures, and foundations were performed. Area related module cost was found to be constant with design, size, and loading. A curved glass module concept was evaluated and found to have the potential to significantly reduce panel structural costs. Conclusions of the study are: array costs do not vary greatly among the designs evaluated; panel and array costs are strongly dependent on design loading; and the best support configuration is load dependent

Randomized controlled trials and neuro-oncology: should alternative designs be considered?

PubMed

Mansouri, Alireza; Shin, Samuel; Cooper, Benjamin; Srivastava, Archita; Bhandari, Mohit; Kondziolka, Douglas

2015-09-01

Deficiencies in design and reporting of randomized controlled trials (RCTs) hinders interpretability and critical appraisal. The reporting quality of recent RCTs in neuro-oncology was analyzed to assess adequacy of design and reporting. The MEDLINE and EMBASE databases were searched to identify non-surgical RCTs (years 2005-2014, inclusive). The CONSORT and Jadad scales were used to assess the quality of design/reporting. Studies published in 2005-2010 were compared as a cohort against studies published in 2011-2014, in terms of general characteristics and reporting quality. A PRECIS-based scale was used to designate studies on the pragmatic-explanatory continuum. Spearman's test was used to assess correlations. Regression analysis was used to assess associations. Overall 68 RCTs were identified. Studies were often chemotherapy-based (n = 41 studies) focusing upon high grade gliomas (46 %) and metastases (41 %) as the top pathologies. Multi-center trials (71 %) were frequent. The overall median CONSORT and Jadad scores were 34.5 (maximum 44) and 2 (maximum 5), respectively; these scores were similar in radiation and chemotherapy-based trials. Major areas of deficiency pertained to allocation concealment, implementation of methods, and blinding whereby less than 20 % of articles fulfilled all criteria. Description of intervention, random sequence generation, and the details regarding recruitment were also deficient; less than 50 % of studies fulfilled all criteria. Description of sample size calculations and blinding improved in later published cohorts. Journal impact factor was significantly associated with higher quality (p = 0.04). Large academic consortia, multi-center designs, ITT analysis, collaboration with biostatisticians, larger sample sizes, and studies with pragmatic objectives were more likely to achieve positive primary outcomes on univariate analysis; none of these variables were significant on multivariate analysis. Deficiencies in the quality of design/reporting of RCTs in neuro-oncology persist. Quality improvement is necessary. Consideration of alternative strategies should be considered.

Postnatal paternal depressive symptoms associated with fathers' subsequent parenting: findings from the Millennium Cohort Study.

PubMed

Nath, Selina; Russell, Ginny; Ford, Tamsin; Kuyken, Willem; Psychogiou, Lamprini

2015-12-01

Impaired parenting may lie on the causal pathway between paternal depression and children's outcomes. We use the first four surveys of the Millennium Cohort Study to investigate the association between paternal depressive symptoms and fathers' parenting (negative, positive and involvement). Findings suggest that postnatal paternal depressive symptoms are associated with fathers' negative parenting. This has implications for the design of intervention programmes for parents with depression and young children. © The Royal College of Psychiatrists 2015.

Design of DNA pooling to allow incorporation of covariates in rare variants analysis.

PubMed

Guan, Weihua; Li, Chun

2014-01-01

Rapid advances in next-generation sequencing technologies facilitate genetic association studies of an increasingly wide array of rare variants. To capture the rare or less common variants, a large number of individuals will be needed. However, the cost of a large scale study using whole genome or exome sequencing is still high. DNA pooling can serve as a cost-effective approach, but with a potential limitation that the identity of individual genomes would be lost and therefore individual characteristics and environmental factors could not be adjusted in association analysis, which may result in power loss and a biased estimate of genetic effect. For case-control studies, we propose a design strategy for pool creation and an analysis strategy that allows covariate adjustment, using multiple imputation technique. Simulations show that our approach can obtain reasonable estimate for genotypic effect with only slight loss of power compared to the much more expensive approach of sequencing individual genomes. Our design and analysis strategies enable more powerful and cost-effective sequencing studies of complex diseases, while allowing incorporation of covariate adjustment.

Motivational Profiles and Their Associations with Achievement Outcomes

ERIC Educational Resources Information Center

Shen, Bo; McCaughtry, Nate; Martin, Jeffrey J.; Fahlman, Mariane M.

2009-01-01

With the belief that theoretical integration in motivation may help us better understand motivational behavior, we designed this study to explore adolescents' motivational profiles and their associations with knowledge acquisition, leisure-time exercise behaviors, and cardiorespiratory fitness. Middle school students from a large urban inner-city…

Mixed Methods Design Study Investigating the Use of a Music Authentic Performance Assessment Tool by High School Band Directors to Measure Student Musical Growth

ERIC Educational Resources Information Center

Beason, Christine F.

2017-01-01

This research project was designed to determine if the Model Cornerstone Assessment for Performance, Proficient level, published by the National Association for Music Education would be an appropriate tool to use to demonstrate student growth as one element of teacher evaluations, specifically the T-TESS. This study focused on four main research…

Environmental risk factors for autism: an evidence-based review of systematic reviews and meta-analyses.

PubMed

Modabbernia, Amirhossein; Velthorst, Eva; Reichenberg, Abraham

2017-01-01

According to recent evidence, up to 40-50% of variance in autism spectrum disorder (ASD) liability might be determined by environmental factors. In the present paper, we conducted a review of systematic reviews and meta-analyses of environmental risk factors for ASD. We assessed each review for quality of evidence and provided a brief overview of putative mechanisms of environmental risk factors for ASD. Current evidence suggests that several environmental factors including vaccination, maternal smoking, thimerosal exposure, and most likely assisted reproductive technologies are unrelated to risk of ASD. On the contrary, advanced parental age is associated with higher risk of ASD. Birth complications that are associated with trauma or ischemia and hypoxia have also shown strong links to ASD, whereas other pregnancy-related factors such as maternal obesity, maternal diabetes, and caesarian section have shown a less strong (but significant) association with risk of ASD. The reviews on nutritional elements have been inconclusive about the detrimental effects of deficiency in folic acid and omega 3, but vitamin D seems to be deficient in patients with ASD. The studies on toxic elements have been largely limited by their design, but there is enough evidence for the association between some heavy metals (most important inorganic mercury and lead) and ASD that warrants further investigation. Mechanisms of the association between environmental factors and ASD are debated but might include non-causative association (including confounding), gene-related effect, oxidative stress, inflammation, hypoxia/ischemia, endocrine disruption, neurotransmitter alterations, and interference with signaling pathways. Compared to genetic studies of ASD, studies of environmental risk factors are in their infancy and have significant methodological limitations. Future studies of ASD risk factors would benefit from a developmental psychopathology approach, prospective design, precise exposure measurement, reliable timing of exposure in relation to critical developmental periods and should take into account the dynamic interplay between gene and environment by using genetically informed designs.

Aquatic macroinvertebrates associated with Schoenoplectus litter in a constructed wetland in California (USA)

USGS Publications Warehouse

Nelson, S.M.; Thullen, J.S.

2008-01-01

Culm processing characteristics were associated with differences in invertebrate density in a study of invertebrates and senesced culm packs in a constructed treatment wetland. Invertebrate abundance differed by location within the wetland and there were differences between the two study years that appeared to be related to water quality and condition of culm material. Open areas in the wetland appeared to be critical in providing dissolved oxygen (DO) and food (plankton) to the important invertebrate culm processor, Glyptotendipes. As culm packs aged, invertebrate assemblages became less diverse and eventually supported mostly tubificid worms and leeches. It appears from this study that wetland design is vital to processing of plant material and that designs that encourage production and maintenance of high DO's will encourage microbial and invertebrate processing of material.

A systematic review of diet quality indices in relation to obesity.

PubMed

Asghari, Golaleh; Mirmiran, Parvin; Yuzbashian, Emad; Azizi, Fereidoun

2017-04-01

Tools, called 'diet/dietary quality indices', evaluate the level of adherence to a specified pattern or a set of recommendations in populations. Yet, there are no review studies providing unanimous comprehensive results of dietary indices on obesity. We reviewed observational studies, focusing on the association of diet quality indices with general obesity or abdominal obesity in adults. We systematically conducted a search in all English language publications available on MEDLINE, ISI Web of Science and Embase between January 1990 and January 2016. Among the wide variety of indices and weight-derived variables, studies with dietary-guideline-based indices and mean changes for weight gain or OR for general obesity and abdominal obesity were selected. From a total of 479 articles, thirty-four studies were selected for the current review, ten of which had prospective designs and twenty-six had cross-sectional designs. Associations of weight status with the original Healthy Eating Index (HEI) and other versions of the HEI including alternative HEI, HEI-2005 and HEI-05 were examined in thirteen studies, with ten studies revealing significant associations. The HEI was a better general obesity predictor in men than in women. Diet scores lacked efficacy in assessing overall diet quality and demonstrated no significant findings in developing countries, in comparison with US populations. In addition, indices based on dietary diversity scores were directly associated with weight gain. Despite the insufficient evidence to draw definitive conclusions about the relation between dietary indices and obesity, HEI was found to be inversely associated with obesity and diversity-based indices were positively associated with obesity.

Application of the stepwise focusing method to optimize the cost-effectiveness of genome-wide association studies with limited research budgets for genotyping and phenotyping.

PubMed

Ohashi, J; Clark, A G

2005-05-01

The recent cataloguing of a large number of SNPs enables us to perform genome-wide association studies for detecting common genetic variants associated with disease. Such studies, however, generally have limited research budgets for genotyping and phenotyping. It is therefore necessary to optimize the study design by determining the most cost-effective numbers of SNPs and individuals to analyze. In this report we applied the stepwise focusing method, with two-stage design, developed by Satagopan et al. (2002) and Saito & Kamatani (2002), to optimize the cost-effectiveness of a genome-wide direct association study using a transmission/disequilibrium test (TDT). The stepwise focusing method consists of two steps: a large number of SNPs are examined in the first focusing step, and then all the SNPs showing a significant P-value are tested again using a larger set of individuals in the second focusing step. In the framework of optimization, the numbers of SNPs and families and the significance levels in the first and second steps were regarded as variables to be considered. Our results showed that the stepwise focusing method achieves a distinct gain of power compared to a conventional method with the same research budget.

Maternal DNA hypomethylation and congenital heart defects

PubMed Central

Chowdhury, Shimul; Cleves, Mario A.; MacLeod, Stewart L.; James, S. Jill; Zhao, Weizhi; Hobbs, Charlotte A.

2011-01-01

Background Congenital heart defects (CHDs) are among the most prevalent and serious of birth defects. Multiple maternal factors are thought to contribute to CHD development including folate intake. Maternal DNA methylation, which is dependent on folate metabolism, may impact the risk of CHDs. Objective Our study was designed to determine whether maternal long interspersed nucleotide elements-1 (LINE-1) DNA hypomethylation is associated with increased occurrence of non-syndromic CHDs and whether maternal folate-dependent metabolites are correlated with DNA methylation status. Design Using a case-control study design, we measured global DNA methylation status among mothers whose pregnancies were affected by non-syndromic CHDs (n=180) and mothers of unaffected pregnancies (n=187). Methylation of LINE-1 was used as a surrogate marker of global DNA methylation status. The association between DNA methylation and CHD risk was determined while adjusting for selected lifestyle factors. Results LINE-1 DNA methylation was significantly lower in cases compared with controls (p=0.049). After covariate adjustments, a significant difference between cases and controls remained (p=0.010). Among women with LINE-1 methylation in the lowest decile of DNA methylation, the estimated risk of having a CHD-affected pregnancy was almost twice that of women in all other deciles (OR=1.91; 95% CI: 1.03, 3.58). Conclusions Our findings indicate that maternal LINE-1 DNA hypomethylation is associated with an increased risk of CHDs. Future studies investigating the association between maternal DNA methylation patterns and CHDs should be pursued. PMID:21254366

Mindfulness-based interventions with youth: A comprehensive meta-analysis of group-design studies.

PubMed

Klingbeil, David A; Renshaw, Tyler L; Willenbrink, Jessica B; Copek, Rebecca A; Chan, Kai Tai; Haddock, Aaron; Yassine, Jordan; Clifton, Jesse

2017-08-01

The treatment effects of Mindfulness-Based Interventions (MBIs) with youth were synthesized from 76 studies involving 6121 participants. A total of 885 effect sizes were aggregated using meta-regression with robust variance estimation. Overall, MBIs were associated with small treatment effects in studies using pre-post (g=0.305, SE=0.039) and controlled designs (g=0.322, SE=0.040). Treatment effects were measured after a follow-up period in 24 studies (n=1963). Results demonstrated that treatment effects were larger at follow-up than post-treatment in pre-post (g=0.462, SE=0.118) and controlled designs (g=0.402, SE=0.081). Moderator analyses indicated that intervention setting and intervention dosage were not meaningfully related to outcomes after controlling for study design quality. With that said, the between-study heterogeneity in the intercept-only models was consistently small, thus limiting the amount of variance for the moderators to explain. A series of exploratory analyses were used to investigate the differential effectiveness of MBIs across four therapeutic process domains and seven therapeutic outcome domains. Small, positive results were generally observed across the process and outcome domains. Notably, MBIs were associated with moderate effects on the process variable of mindfulness in controlled studies (n=1108, g=0.510). Limitations and directions for future research and practice are discussed. Copyright © 2017 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Usability of patient-centered health IT: mixed-methods usability study of ePill.

PubMed

Schmidt-Kraepelin, Manuel; Dehling, Tobias; Sunyaev, Ali

2014-01-01

To facilitate use of patient-centered health IT applications in everyday life, a high degree of usability is required. Based on the example of a patient-centered web application, we propose a usability study design enabling developers and researchers to assess usability of patient-centered health IT applications and derive implications for their improvement. Our study design integrates tasks that subjects have to process, an associated questionnaire based on Perceived Ease of Use, Perceived Usefulness, Attitude Toward Using, and Behavioral Intention to Use, a System Usability Scale questionnaire, and focus groups. Application of the usability study design demonstrates its feasibility and provides insights for assessment of usability in related projects in research and practice.

Remote sensing in Virginia agriculture

NASA Technical Reports Server (NTRS)

Pettry, D. E.; Newhouse, M. E.; Dunton, E. M., Jr.; Scott, J. H., Jr.

1972-01-01

An experimental investigation, designed to develop and evaluate multispectral sensing techniques used in sensing agricultural crops, is described. Initial studies were designed to detect plant species and associated diseases, soil variations, and cultural practices under natural environment conditions. In addition, crop varieties, age, spacing, plant height, percentage of ground cover, and plant vigor are determined.

Advancing Virtual Patient Simulations through Design Research and InterPLAY: Part I--Design and Development

ERIC Educational Resources Information Center

Hirumi, Atsusi; Kleinsmith, Andrea; Johnsen, Kyle; Kubovec, Stacey; Eakins, Michael; Bogert, Kenneth; Rivera-Gutierrez, Diego J.; Reyes, Ramsamooj Javier; Lok, Benjamin; Cendan, Juan

2016-01-01

Systematic reviews and meta-analyses of randomized controlled studies conclude that virtual patient simulations are consistently associated with higher learning outcomes compared to other educational methods. However, we cannot assume that students will learn from simply exposing students to the simulations. The instructional features that are…

When Control Groups Do Not Exist: Program Evaluation without a Net.

ERIC Educational Resources Information Center

Clark, Sheldon B.; And Others

Suggestions, based on the experience of researchers at Oak Ridge (Tennessee) Associated Universities (ORAU), are offered on how evaluations in which true experimental designs are not possible can be designed for meaningful comparison. The ORAU conducts evaluation and assessment studies of educational programs intended to explore some aspect of the…

A Randomized Crossover Study of Web-Based Media Literacy to Prevent Smoking

ERIC Educational Resources Information Center

Shensa, Ariel; Phelps-Tschang, Jane; Miller, Elizabeth; Primack, Brian A.

2016-01-01

Feasibly implemented Web-based smoking media literacy (SML) programs have been associated with improving SML skills among adolescents. However, prior evaluations have generally had weak experimental designs. We aimed to examine program efficacy using a more rigorous crossover design. Seventy-two ninth grade students completed a Web-based SML…

Application of advanced technologies to small, short-haul transport aircraft (STAT)

NASA Technical Reports Server (NTRS)

Kraus, E. F.; Mall, O. D.; Awker, R. W.; Scholl, J. W.

1982-01-01

The benefits of selected advanced technologies for 19 and 30 passenger, short-haul aircraft were identified. Advanced technologies were investigated in four areas: aerodynamics, propulsion, structures, and ride quality. Configuration sensitivity studies were conducted to show design tradeoffs associated with passenger capacity, cabin comfort level, and design field length.

Design Implications of Real-Time Feedback in Continuous Combinatorial Auctions: An Experimental Investigation

ERIC Educational Resources Information Center

Sanyal, Pallab

2009-01-01

Information Technology (IT) has spawned the growth of novel and innovative market mechanisms (such as online auctions) and associated businesses (such as eBay and Priceline) that were not feasible without the capabilities and reach of these modern information technologies. Previous studies on designing trading mechanisms for online markets…

Factor Structure of the Behavior Flexibility Rating Scale (BFRS)

ERIC Educational Resources Information Center

Pituch, Keenan A.; Green, Vanessa A.; Sigafoos, Jeff; Itchon, Jonathan; O'Reilly, Mark; Lancioni, Giulio E.; Didden, Robert

2007-01-01

The Behavior Flexibility Rating Scale (BFRS) is designed to assess insistence on sameness or lack of behavioral flexibility, which is often associated with autism and other developmental disabilities. This study was designed to assess the factor structure of this scale for a sample of 968 individuals with autism, Asperger's syndrome, and Down…

Navigating Past and Present Accountability Measures in Search of an Effective Principal Professional Development Model

ERIC Educational Resources Information Center

Martin, Patrick M.

2012-01-01

This study was designed to investigate the perceived experiences encountered by principals in the state of Illinois regarding professional development sessions offered through the Illinois Administrator Academy. The fundamental value of the Illinois Administrator Academy was designed as one of 169 specific initiatives in association with the…

A study on design and development of enterprise-wide concepts for clinical documentation templates.

PubMed

Zhou, Li; Gurjar, Rupali; Regier, Rachel; Morgan, Stephen; Meyer, Theresa; Aroy, Teal; Goldman, Debora Scavone; Hongsermeier, Tonya; Middleton, Blackford

2008-11-06

Structured clinical documents are associated with many potential benefits. Underlying terminologies and structure of information are keys to their successful implementation and use. This paper presents a methodology for design and development of enterprise-wide concepts for clinical documentation templates for an ambulatory Electronic Medical Record (EMR) system.

Design and Usability of Digital Libraries: Case Studies in the Asia Pacific

ERIC Educational Resources Information Center

Theng, Yin-Leng, Ed.; Foo, Schubert, Ed.

2005-01-01

This book showcases some of the best digital library practices from organizations in the Asia Pacific. Particular emphasis has been placed on the design, use and usability of digital libraries. Not only are digital libraries examined, but related technologies, the management of knowledge in digital libraries, and the associated usability and…

Where Are We? An Analysis of the Methods and Focus of the Research on Simulation Gaming.

ERIC Educational Resources Information Center

Butler, Richard J.; And Others

1988-01-01

Designed to determine whether research in simulation and gaming follows research design methodology and the degree to which research is directed toward learning outcomes measured by Bloom's taxonomy of educational objectives, this article examines studies reported in proceedings from the Association for Business Simulation and Experiential…

Conceptual design and analysis of a dynamic scale model of the Space Station Freedom

NASA Technical Reports Server (NTRS)

Davis, D. A.; Gronet, M. J.; Tan, M. K.; Thorne, J.

1994-01-01

This report documents the conceptual design study performed to evaluate design options for a subscale dynamic test model which could be used to investigate the expected on-orbit structural dynamic characteristics of the Space Station Freedom early build configurations. The baseline option was a 'near-replica' model of the SSF SC-7 pre-integrated truss configuration. The approach used to develop conceptual design options involved three sets of studies: evaluation of the full-scale design and analysis databases, conducting scale factor trade studies, and performing design sensitivity studies. The scale factor trade study was conducted to develop a fundamental understanding of the key scaling parameters that drive design, performance and cost of a SSF dynamic scale model. Four scale model options were estimated: 1/4, 1/5, 1/7, and 1/10 scale. Prototype hardware was fabricated to assess producibility issues. Based on the results of the study, a 1/4-scale size is recommended based on the increased model fidelity associated with a larger scale factor. A design sensitivity study was performed to identify critical hardware component properties that drive dynamic performance. A total of 118 component properties were identified which require high-fidelity replication. Lower fidelity dynamic similarity scaling can be used for non-critical components.

Can Co-Curricular Activities Enhance the Learning Effectiveness of Students?: An Application to the Sub-Degree Students in Hong Kong

ERIC Educational Resources Information Center

Leung, Chi-Hung; Ng, Chi Wing Raymond; Chan, Po On Ella

2011-01-01

A total of 575 students from the Associate Degree Foundation Program and the Associate Degree Program participated in this study. The two purposes of this study were to use the time series between/within experimental design to examine whether participation in co-curricular activities could (1) enhance student learning effectiveness and (2) have…

Accountability Policy Outcomes Related to No Child Left Behind and Educational Equity for Big5 City Schools in New York State

ERIC Educational Resources Information Center

Shin, Hyejin

2016-01-01

The purpose of this study was to explore the association of NCLB/accountability with educational output and input for New York State, collectively. Focusing on ELA and Math achievement in 4th and 8th grades, this study demonstrated the association of accountability outcomes in three ways: "accountability design, school proficiency level, and…

A Study Investigating How Concepts Associated with Eating Disorders Are Addressed in a Preventative Context in the Home Economics Classroom.

ERIC Educational Resources Information Center

Jones, Karen H.; Nagel, K. L.

A study was designed to determine the following: (1) if concepts associated with eating disorders are being addressed in home economics courses; (2) through what context the concepts are presented; and (3) if the following variables affect whether, with which emphasis, and in what context the teacher presents concepts--having previous personal…

Gender-Related Discourses as Mediators in the Association between Internalization of the Thin-Body Ideal and Indicants of Body Dissatisfaction and Disordered Eating

ERIC Educational Resources Information Center

Morrison, Todd G.; Sheahan, Emer E.

2009-01-01

This study examined whether the gender-related discourses of self-objectification, self-silencing, and anger suppression mediated the association between internalization of the thin-body ideal and body dissatisfaction and eating pathology. We employed a cross-sectional design to study both university (n = 140) and community (n = 76) samples of…

Determining Biology Student Teachers' Cognitive Structure on the Concept of "Diffusion" through the Free Word-Association Test and the Drawing-Writing Technique

ERIC Educational Resources Information Center

Kurt, Hakan; Ekici, Gülay; Aktas, Murat; Aksu, Özlem

2013-01-01

The aim of the current study is to investigate student biology teachers' cognitive structures related to "diffusion" through the free word-association test and the drawing-writing technique. As the research design of the study, the qualitative research method was applied. The data were collected from 44 student biology teachers. The free…

Associations between Objectively Measured Physical Activity, Cardiorespiratory Fitness and Risk Factors for Metabolic Syndrome in 12- to 15-Year-Old Tianjin City Children

ERIC Educational Resources Information Center

Tan, Sijie; Wang, Jianxiong; Zhang, Yibing; Zhang, Chen

2015-01-01

Objective: The study aim was to explore associations between daily physical activity level, cardiorespiratory fitness and metabolic syndrome among Chinese children. Design: We conducted a school-based, cross-sectional study. Setting: Participants including 112 boys and 121 girls were recruited from three schools in the urban suburbs of Tianjin…

Comparative safety and effectiveness of perinatal antiretroviral therapies for HIV-infected women and their children: Systematic review and network meta-analysis including different study designs.

PubMed

Veroniki, Areti Angeliki; Antony, Jesmin; Straus, Sharon E; Ashoor, Huda M; Finkelstein, Yaron; Khan, Paul A; Ghassemi, Marco; Blondal, Erik; Ivory, John D; Hutton, Brian; Gough, Kevin; Hemmelgarn, Brenda R; Lillie, Erin; Vafaei, Afshin; Tricco, Andrea C

2018-01-01

Nearly all newly infected children acquire Human Immunodeficiency virus (HIV) via mother-to-child transmission (MTCT) during pregnancy, labour or breastfeeding from untreated HIV-positive mothers. Antiretroviral therapy (ART) is the standard care for pregnant women with HIV. However, evidence of ART effectiveness and harms in infants and children of HIV-positive pregnant women exposed to ART has been largely inconclusive. The aim of our systematic review and network meta-analysis (NMA) was to evaluate the comparative safety and effectiveness of ART drugs in children exposed to maternal HIV and ART (or no ART/placebo) across different study designs. We searched MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials (inception until December 7, 2015). Primary outcomes were any congenital malformations (CMs; safety), including overall major and minor CMs, and mother-to-child transmission (MTCT; effectiveness). Random-effects Bayesian pairwise meta-analyses and NMAs were conducted. After screening 6,468 citations and 1,373 full-text articles, 90 studies of various study designs and 90,563 patients were included. The NMA on CMs (20 studies, 7,503 children, 16 drugs) found that none of the ART drugs examined here were associated with a significant increase in CMs. However, zidovudine administered with lamivudine and indinavir was associated with increased risk of preterm births, zidovudine administered with nevirapine was associated with increased risk of stillbirths, and lamivudine administered with stavudine and efavirenz was associated with increased risk of low birth weight. A NMA on MTCT (11 studies, 10,786 patients, 6 drugs) found that zidovudine administered once (odds ratio [OR] = 0.39, 95% credible interval [CrI]: 0.19-0.83) or twice (OR = 0.43, 95% CrI: 0.21-0.68) was associated with significantly reduced risk of MTCT. Our findings suggest that ART drugs are not associated with an increased risk of CMs, yet some may increase adverse birth events. Some ART drugs (e.g., zidovudine) effectively reduce MTCT.

Rare variant association analysis in case-parents studies by allowing for missing parental genotypes.

PubMed

Li, Yumei; Xiang, Yang; Xu, Chao; Shen, Hui; Deng, Hongwen

2018-01-15

The development of next-generation sequencing technologies has facilitated the identification of rare variants. Family-based design is commonly used to effectively control for population admixture and substructure, which is more prominent for rare variants. Case-parents studies, as typical strategies in family-based design, are widely used in rare variant-disease association analysis. Current methods in case-parents studies are based on complete case-parents data; however, parental genotypes may be missing in case-parents trios, and removing these data may lead to a loss in statistical power. The present study focuses on testing for rare variant-disease association in case-parents study by allowing for missing parental genotypes. In this report, we extended the collapsing method for rare variant association analysis in case-parents studies to allow for missing parental genotypes, and investigated the performance of two methods by using the difference of genotypes between affected offspring and their corresponding "complements" in case-parent trios and TDT framework. Using simulations, we showed that, compared with the methods just only using complete case-parents data, the proposed strategy allowing for missing parental genotypes, or even adding unrelated affected individuals, can greatly improve the statistical power and meanwhile is not affected by population stratification. We conclude that adding case-parents data with missing parental genotypes to complete case-parents data set can greatly improve the power of our strategy for rare variant-disease association.

Associations between ankle-brachial index and cognitive function: results from the Lifestyle Interventions and Independence for Elders trial

USDA-ARS?s Scientific Manuscript database

OBJECTIVE: The objective of this study was to evaluate cross-sectional and longitudinal associations between ankle-brachial index (ABI) and indicators of cognitive function. DESIGN: Randomized clinical trial (Lifestyle Interventions and Independence for Elders Trial). SETTING: Eight US academic ce...

Fast food perceptions, intake and association with obesity in the United States: a systematic review

USDA-ARS?s Scientific Manuscript database

Objective: To examine Americans’ perception of fast food (FF), their consumption, and its association with obesity risk. Design: We searched PubMed for studies published in English until February 2017 that reported on Americans’ FF intake, perceptions, beliefs, attitudes, and knowledge. Eleven artic...

Marital Distress and Mental Health Care Service Utilization

ERIC Educational Resources Information Center

Schonbrun, Yael Chatav; Whisman, Mark A.

2010-01-01

Objective: This study was designed to evaluate the association between marital distress and mental health service utilization in a population-based sample of men and women (N = 1,601). Method: The association between marital distress and mental health care service utilization was evaluated for overall mental health service utilization and for…

Association analysis and marker development for grain quality traits using USDA diverse rice germplasm collections

USDA-ARS?s Scientific Manuscript database

New molecular markers are being designed and validated for grain quality improvement based on computationally assisted analysis of genome wide association study (GWAS) findings across multiple panels and multiple grain quality traits. The traits include grain dimensions, apparent amylose content (A...

Substance Use and Personal Adjustment among Disadvantaged Teenagers: A Six-Month Prospective Study.

ERIC Educational Resources Information Center

Luthar, Suniya S.; Cushing, Gretta

1997-01-01

Associations between substance abuse and emotional and behavioral adjustment were examined in a two-wave longitudinal design for 138 inner-city ninth graders. Drug use showed associations in expected directions with all indices of adjustment except for peer-related sociability. Implications for interventions are discussed. (SLD)

Differential associations between maternal scaffolding and toddler emotion regulation in toddlers born preterm and full term

PubMed Central

Erickson, Sarah J.; Duvall, Susanne W.; Fuller, Janell; Schrader, Ron; MacLean, Peggy; Lowe, Jean

2013-01-01

Background Parental “scaffolding” behavior has been associated with developmental outcomes in at-risk children. Aims Because there are limited empirical data regarding how scaffolding is associated with emotion-based developmental skills, the purpose of this study was to compare associations between maternal verbal scaffolding and toddler emotion regulation, including fewer displays of negative affect and increased contentment and enjoyment during play, in toddlers born preterm and full term. Study Design This study was a cross-sectional cohort design. Maternal and toddler behavior was assessed during 5 minutes of videotaped free play with standardized toys. Subjects 131 toddlers (18-22 months) and their mothers were included (77 born preterm; 54 born full term). Outcome Measures Toddler emotion regulation, negative affect, and dyadic mutual enjoyment were coded from videotaped play. Results The association between maternal scaffolding and emotion regulation was different for dyads with a toddler born preterm versus full term, wherein the association was positive for toddlers born preterm and non-significant for toddlers born full term. Similarly, the association between maternal scaffolding and negative affect was different for the two groups: negative for toddlers born preterm and non-significant for toddlers born full term. Finally, the association between maternal scaffolding and mutual enjoyment was positive for toddlers born preterm and non-significant for toddlers born full term. Conclusions Our findings highlight early differences in mother-child interactive style correlates of children born preterm compared to those born full term. Maternal scaffolding behavior may be uniquely associated with emotion regulation and a positive dyadic encounter for toddlers born preterm. PMID:23773306

Does Loneliness Necessarily Lead to a Decrease in Prosocial Behavior? The Roles of Gender and Situation.

PubMed

Huang, Heqing; Liu, Yanchun; Liu, Xiaocen

2016-01-01

Although, previous studies show overwhelming evidence that loneliness is negatively correlated with prosocial behavior, some theories and research have implied that under certain situations, loneliness plays a positive role in an individual's social functioning. The two studies reported in this article examined loneliness and its associations with prosocial behavior in Chinese adults using subjective reporting and experimental design. Study 1 examined 305 Chinese adults (175 males) using the Social and Emotional Loneliness Scale for Adults and the Prosocial Tendencies Measure to evaluate their loneliness and prosocial tendencies. The results showed that loneliness was negatively associated with all prosocial tendencies except the public prosocial tendency. Study 2 examined 177 Chinese adults (61 males) using an experimental design and found that only lonely women in public situations expressed a greater willingness to help. The results also suggest that loneliness may play a positive role in the social functioning of individuals under certain conditions. The function of loneliness and the implications of the association between loneliness and prosocial behavior are discussed.

Does Loneliness Necessarily Lead to a Decrease in Prosocial Behavior? The Roles of Gender and Situation

PubMed Central

Huang, Heqing; Liu, Yanchun; Liu, Xiaocen

2016-01-01

Although, previous studies show overwhelming evidence that loneliness is negatively correlated with prosocial behavior, some theories and research have implied that under certain situations, loneliness plays a positive role in an individual's social functioning. The two studies reported in this article examined loneliness and its associations with prosocial behavior in Chinese adults using subjective reporting and experimental design. Study 1 examined 305 Chinese adults (175 males) using the Social and Emotional Loneliness Scale for Adults and the Prosocial Tendencies Measure to evaluate their loneliness and prosocial tendencies. The results showed that loneliness was negatively associated with all prosocial tendencies except the public prosocial tendency. Study 2 examined 177 Chinese adults (61 males) using an experimental design and found that only lonely women in public situations expressed a greater willingness to help. The results also suggest that loneliness may play a positive role in the social functioning of individuals under certain conditions. The function of loneliness and the implications of the association between loneliness and prosocial behavior are discussed. PMID:27695429

Andexanet alfa to reverse the anticoagulant activity of factor Xa inhibitors: a review of design, development and potential place in therapy.

PubMed

Sartori, Michelangelo; Cosmi, Benilde

2018-04-01

Direct oral anticoagulants are associated with rates of major bleeding which are not negligible, albeit lower than those associated with vitamin K antagonists. No specific reversal agent for factor Xa (FXa) direct inhibitors is currently available for clinical use. A modified activated human FXa decoy protein, andexanet alfa, is being developed that binds FXa direct inhibitors in their active site, thus reversing their anticoagulant effect. The purpose of this article is to review the design, development and clinical trials of andexanet alfa. Andexanet alfa was shown to reverse FXa inhibitors anticoagulant activity both in thrombosis animal models, healthy volunteers and patients with acute major bleeding. Andexanet alfa has been studied in double-blind, placebo-controlled phase II and III studies. A preliminary report of the phase III study showed that an effective hemostasis was obtained after andexanet alfa infusion in the majority of the patients with acute major bleeding associated with FXa inhibitors. Additional studies are ongoing and andexanet alfa is expected to be launched in the market in the near future.

Enroute flight-path planning - Cooperative performance of flight crews and knowledge-based systems

NASA Technical Reports Server (NTRS)

Smith, Philip J.; Mccoy, Elaine; Layton, Chuck; Galdes, Deb

1989-01-01

Interface design issues associated with the introduction of knowledge-based systems into the cockpit are discussed. Such issues include not only questions about display and control design, they also include deeper system design issues such as questions about the alternative roles and responsibilities of the flight crew and the computer system. In addition, the feasibility of using enroute flight path planning as a context for exploring such research questions is considered. In particular, the development of a prototyping shell that allows rapid design and study of alternative interfaces and system designs is discussed.

Multilocus family-based association analysis of seven candidate polymorphisms with essential hypertension in an african-derived semi-isolated brazilian population.

PubMed

Kimura, L; Angeli, C B; Auricchio, M T B M; Fernandes, G R; Pereira, A C; Vicente, J P; Pereira, T V; Mingroni-Netto, R C

2012-01-01

Background. It has been widely suggested that analyses considering multilocus effects would be crucial to characterize the relationship between gene variability and essential hypertension (EH). Objective. To test for the presence of multilocus effects between/among seven polymorphisms (six genes) on blood pressure-related traits in African-derived semi-isolated Brazilian populations (quilombos). Methods. Analyses were carried out using a family-based design in a sample of 652 participants (97 families). Seven variants were investigated: ACE (rs1799752), AGT (rs669), ADD2 (rs3755351), NOS3 (rs1799983), GNB3 (rs5441 and rs5443), and GRK4 (rs1801058). Sensitivity analyses were further performed under a case-control design with unrelated participants only. Results. None of the investigated variants were associated individually with both systolic and diastolic BP levels (SBP and DBP, respectively) or EH (as a binary outcome). Multifactor dimensionality reduction-based techniques revealed a marginal association of the combined effect of both GNB3 variants on DBP levels in a family-based design (P = 0.040), whereas a putative NOS3-GRK4 interaction also in relation to DBP levels was observed in the case-control design only (P = 0.004). Conclusion. Our results provide limited support for the hypothesis of multilocus effects between/among the studied variants on blood pressure in quilombos. Further larger studies are needed to validate our findings.

Maximizing Patient Recruitment and Retention in a Secondary Stroke Prevention Clinical Trial: Lessons Learned from the STAND FIRM Study.

PubMed

Thayabaranathan, Tharshanah; Cadilhac, Dominique A; Srikanth, Velandai K; Fitzgerald, Sharyn M; Evans, Roger G; Kim, Joosup; Gerraty, Richard P; Phan, Thanh G; Bladin, Christopher F; Nelson, Mark R; Frayne, Judith H; Thrift, Amanda G

2016-06-01

Recruitment and retention of patients in a clinical trial is important for generalizability and robustness of findings. We aimed to investigate features of a study design that were associated with recruitment and retention in a Phase II and Phase III trial of a secondary prevention program for stroke. Following informed consent in hospital, Phase II participants were randomized to intervention or usual care. Baseline clinical assessments were conducted at home approximately 3 months after discharge. In Phase III study, informed consent was obtained at home. We compared the characteristics of participants recruited and retained to 12 months for both phases. Interviews with study nurses were undertaken in order to ascertain their opinions of features of study design. Triangulation was used to identify the features of study design that nurses thought had improved recruitment and retention. All 24 eligible participants were recruited to the Phase II pilot study (100% recruitment), with 67% retention at 12 months. In Phase III study, 570 participants were recruited, and 93% of these participants had reached their 12-month assessment (n = 532) and were still participating. Consistent with the greater patient retention in Phase III study, nurses reported that patients' willingness to participate was greater when consent was obtained at home. Following a change in the consent process from hospital to home, more participants continued participation to 12 months. Pilot studies can provide important data to improve study design and better understand potential barriers to recruitment and retention. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

The Theory of Planned Behaviour and dietary patterns: A systematic review and meta-analysis.

PubMed

McDermott, M S; Oliver, M; Simnadis, T; Beck, E J; Coltman, T; Iverson, D; Caputi, P; Sharma, R

2015-12-01

Promoting adherence to healthy dietary patterns is a critical public health issue. Models of behaviour, such as the Theory of Planned Behaviour (TPB) allow programme designers to identify antecedents of dietary patterns and design effective interventions. The primary aim of this study was to examine the association between TPB variables and dietary patterns. A systematic literature search was conducted to identify relevant studies. Random-effects meta-analysis was used to calculate average correlations. Meta-regression was used to test the impact of moderator variables. In total, 22 reports met the inclusion criteria. Attitudes had the strongest association with intention (r+=0.61) followed by perceived behavioural control (PBC, r+=0.46) and subjective norm (r+=0.35). The association between intention and behaviour was r+=0.47, and between PBC and behaviour r+=0.32. Moderator analyses revealed that younger participants had stronger PBC-behaviour associations than older participants had, and studies recording participants' perceptions of behaviour reported significantly higher intention-behaviour associations than did those using less subjective measures. TPB variables were found to have medium to large associations with both intention and behaviour that were robust to the influence of key moderators. Recommendations for future research include further examination of the moderation of TPB variables by age and gender and the use of more valid measures of eating behaviour. Copyright © 2015 Elsevier Inc. All rights reserved.

Office type's association to employees' welfare: Three studies.

PubMed

Danielsson, Christina Bodin

2016-08-12

The workplace is important for employees' daily life and well-being. This article investigates exploratory the office design's role for employees' welfare from different perspectives. By comparing different studies of the office, type's influence on different factors of employees' welfare the aim is to see if any common patterns exist in office design's impact. The three included studies investigate office type's association with employees' welfare by measuring its influence on: a) perception of leadership, b) sick leave, and c) job satisfaction.The sample consists of office employees from a large, national representative work environment survey that work in one of the seven identified office types in contemporary office design: (1) cell-offices; (2) shared-room offices; (3) small, (4) medium-sized and (5) large open-plan offices; (6) flex-offices and (7) combi-offices. Statistical method used is multivariate logistic and linear regression analysis with adjustment for background factors. Overall results show that shared-room office, traditional open plan offices and flex-office stand out negatively, but to different degree(s) on the different outcomes measured. This explorative comparison of different studies finds a pattern of office types that repeatedly show indications of negative influence on employees' welfare, but further studies are needed to clarify this.

A note on the efficiencies of sampling strategies in two-stage Bayesian regional fine mapping of a quantitative trait.

PubMed

Chen, Zhijian; Craiu, Radu V; Bull, Shelley B

2014-11-01

In focused studies designed to follow up associations detected in a genome-wide association study (GWAS), investigators can proceed to fine-map a genomic region by targeted sequencing or dense genotyping of all variants in the region, aiming to identify a functional sequence variant. For the analysis of a quantitative trait, we consider a Bayesian approach to fine-mapping study design that incorporates stratification according to a promising GWAS tag SNP in the same region. Improved cost-efficiency can be achieved when the fine-mapping phase incorporates a two-stage design, with identification of a smaller set of more promising variants in a subsample taken in stage 1, followed by their evaluation in an independent stage 2 subsample. To avoid the potential negative impact of genetic model misspecification on inference we incorporate genetic model selection based on posterior probabilities for each competing model. Our simulation study shows that, compared to simple random sampling that ignores genetic information from GWAS, tag-SNP-based stratified sample allocation methods reduce the number of variants continuing to stage 2 and are more likely to promote the functional sequence variant into confirmation studies. © 2014 WILEY PERIODICALS, INC.

Implementation of a nutrition assessment, counseling and support program and its association with body mass index among people living with HIV in Accra, Ghana.

PubMed

Sackey, Joachim; Zhang, Fang Fang; Rogers, Beatrice; Aryeetey, Richmond; Wanke, Christine

2018-05-01

In spite of the important role nutrition plays in the management of HIV, access to nutrition services is inadequate, especially in resource limited settings. In addition, nutrition programs for people living with HIV (PLWH) have not been sufficiently evaluated for efficacy and this study was conducted to address this gap. This study aimed to evaluate the implementation of the nutrition assessment, counseling and support (NACS) program in Accra, Ghana, and to assess whether the level of implementation of NACS was associated with the body mass index (BMI) of PLWH. A cross-sectional study was conducted in six HIV clinics (3 NACS designated and 3 non-NACS). Study participants were 152 adult PLWH at least 6 months on antiretroviral therapy and not pregnant or breastfeeding. Using a NACS implementation scale developed for this study ranging from 0 to 8 (a higher score indicating better NACS implementation), median NACS implementation score was not different between NACS-designated, and non-NACS HIV clinics (5 vs 4, p = 0.14). Almost half (47%) of the respondents were overweight or obese. A higher score on the NACS implementation scale was not significantly associated with overweight or obesity (BMI >24.9 kg/m 2 ) after adjusting for other covariates. It was concluded that, there was poor implementation of NACS in the NACS designated HIV clinics surveyed with no nutrition counseling offered nor food support available to those who might need it.

A Randomized Phase II Dose-Response Exercise Trial among Colon Cancer Survivors: Purpose, Study Design, Methods, and Recruitment Results

PubMed Central

Brown, Justin C.; Troxel, Andrea B.; Ky, Bonnie; Damjanov, Nevena; Zemel, Babette S.; Rickels, Michael R.; Rhim, Andrew D.; Rustgi, Anil K.; Courneya, Kerry S.; Schmitz, Kathryn H.

2016-01-01

Background Observational studies indicate that higher volumes of physical activity are associated with improved disease outcomes among colon cancer survivors. The aim of this report is to describe the purpose, study design, methods, and recruitment results of the COURAGE trial, a National Cancer Institute (NCI) sponsored, phase II, randomized, dose-response exercise trial among colon cancer survivors. Methods/Results The primary objective of the COURAGE trial is to quantify the feasibility, safety, and physiologic effects of low-dose (150 min·wk−1) and high-dose (300 min·wk−1) moderate-intensity aerobic exercise compared to usual-care control group over six months. The exercise groups are provided with in-home treadmills and heart rate monitors. Between January and July 2015, 1,433 letters were mailed using a population-based state cancer registry; 126 colon cancer survivors inquired about participation, and 39 were randomized onto the study protocol. Age was associated with inquiry about study participation (P<0.001) and randomization onto the study protocol (P<0.001). No other demographic, clinical, or geographic characteristics were associated with study inquiry or randomization. The final trial participant was randomized in August 2015. Six month endpoint data collection was completed in February 2016. Discussion The recruitment of colon cancer survivors into an exercise trial is feasible. The findings from this trial will inform key design aspects for future phase 2 and phase 3 randomized controlled trials to examine the efficacy of exercise to improve clinical outcomes among colon cancer survivors. PMID:26970181

Influence of study approaches and course design on academic success in the undergraduate anatomy laboratory.

PubMed

Eleazer, Courtney D; Scopa Kelso, Rebecca

2018-01-04

Many pre-health professional programs require completion of an undergraduate anatomy course with a laboratory component, yet grades in these courses are often low. Many students perceive anatomy as a more challenging subject than other coursework, and the resulting anxiety surrounding this perception may be a significant contributor to poor performance. Well-planned and deliberate guidance from instructors, as well as thoughtful course design, may be necessary to assist students in finding the best approach to studying for anatomy. This article assesses which study habits are associated with course success and whether course design influences study habits. Surveys (n = 1,274) were administered to students enrolled in three undergraduate human anatomy laboratory courses with varying levels of cooperative learning and structured guidance. The surveys collected information on potential predictors of performance, including student demographics, educational background, self-assessment ability, and study methods (e.g., flashcards, textbooks, diagrams). Compared to low performers, high performers perceive studying in laboratory, asking the instructor questions, quizzing alone, and quizzing others as more effective for learning. Additionally, students co-enrolled in a flipped, active lecture anatomy course achieve higher grades and find active learning activities (e.g., quizzing alone and in groups) more helpful for their learning in the laboratory. These results strengthen previous research suggesting that student performance is more greatly enhanced by an active classroom environment that practices successful study strategies rather than one that simply encourages students to employ such strategies inside and outside the classroom. Anat Sci Educ. © 2018 American Association of Anatomists. © 2018 American Association of Anatomists.

Relationship between cigarette smoking and risk of chronic myeloid leukaemia: a meta-analysis of epidemiological studies.

PubMed

Qin, Ling; Deng, Hui-Yang; Chen, Sheng-Jiang; Wei, Wei

2017-05-01

Previous epidemiologic studies that have been reported on the association between cigarette smoking and risk of chronic myeloid leukaemia (CML) have remained controversial. A comprehensive meta-analysis was performed to evaluate smoking as a potential relationship factor and incidence of CML. Systematic literatures collected from articles published before August 2015 were searched from PubMed, EMBASE and the Cochrane Library. A total of 10 studies (nine case-controls and one cohort) met inclusion criteria of this meta-analysis. Odds ratios (ORs) with 95% confidence interval (CI) were calculated to assess the strength of the association between cigarette smoking and risk of CML in this study. Quality assessments were performed on the studies with the Newcastle-Ottawa Scale. I2 index was used to evaluate heterogeneity. Finally, publication bias was assessed through funnel plots and Begger's test. No significant association was observed between ever-smokers and CML when compared among non-smokers (OR = 1.13, 95% CI: 0.99-1.29) or between subgroups stratified by smoking history, gender, geographical region, study design and source of patients. Our results demonstrate that this association was stronger in individuals who smoked <20 cigarettes/day (OR = 1.72, 95% CI: 1.06-2.79) vs. individuals who smoked >20 cigarettes/day (OR = 1.24, 95% CI: 0.55-2.81). Moreover, cumulative smoking of <15, 15-30 and >30 pack-years was associated with ORs of 1.22, 1.32 and 1.39, respectively (P < 0.001, for trend). This meta-analysis suggests that smoking may significantly increase the risk of CML in a dose-dependent manner. However, additional well-designed, prospective cohort studies are required to verify these findings and identify other risk factors associated with CML.

Reproductive and Developmental Toxicity of Formaldehyde: A Systematic Review

PubMed Central

Duong, Anh; Steinmaus, Craig; McHale, Cliona M.; Vaughan, Charles P.; Zhang, Luoping

2011-01-01

Formaldehyde, the recently classified carcinogen and ubiquitous environmental contaminant, has long been suspected of causing adverse reproductive and developmental effects, but previous reviews were inconclusive, due in part, to limitations in the design of many of the human population studies. In the current review, we systematically evaluated evidence of an association between formaldehyde exposure and adverse reproductive and developmental effects, in human populations and in vivo animal studies, in the peer-reviewed literature. The mostly retrospective human studies provided evidence of an association of maternal exposure with adverse reproductive and developmental effects. Further assessment of this association by meta-analysis revealed an increased risk of spontaneous abortion (1.76, 95% CI 1.20–2.59, p=0.002) and of all adverse pregnancy outcomes combined (1.54, 95% CI 1.27–1.88, p<0.001), in formaldehyde-exposed women, although differential recall, selection bias, or confounding cannot be ruled out. Evaluation of the animal studies including all routes of exposure, doses and dosing regimens studied, suggested positive associations between formaldehyde exposure and reproductive toxicity, mostly in males. Potential mechanisms underlying formaldehyde-induced reproductive and developmental toxicities, including chromosome and DNA damage (genotoxicity), oxidative stress, altered level and/or function of enzymes, hormones and proteins, apoptosis, toxicogenomic and epigenomic effects (such as DNA methylation), were identified. To clarify these associations, well-designed molecular epidemiologic studies, that include quantitative exposure assessment and diminish confounding factors, should examine both reproductive and developmental outcomes associated with exposure in males and females. Together with mechanistic and animal studies, this will allow us to better understand the systemic effect of formaldehyde exposure. PMID:21787879

Hospital trauma level's association with outcomes for injured pregnant women and their neonates in Washington state, 1995–2012

PubMed Central

Distelhorst, John Thomas; Soltis, Michele A.; Krishnamoorthy, Vijay; Schiff, Melissa A.

2017-01-01

Background: Trauma occurs in 8% of all pregnancies. To date, no studies have evaluated the effect of the hospital's trauma designation level as it relates to birth outcomes for injured pregnant women. Methods: This population-based, retrospective cohort study evaluated the association between trauma designation levels and injured pregnancy birth outcomes. We linked Washington State Birth and Fetal Death Certificate data and the Washington State Comprehensive Hospital Abstract Recording System. Injury was identified using the International Classification of Diseases, Ninth Revision injury diagnosis and external causation codes. The association was analyzed using logistic regression to estimate odds ratios and 95% confidence intervals (CIs). Results: We identified 2492 injured pregnant women. Most birth outcomes studied, including placental abruption, induction of labor, premature rupture of membranes, cesarean delivery, maternal death, gestational age <37 weeks, fetal distress, fetal death, neonatal respiratory distress, and neonatal death, showed no association with trauma hospital level designation. Patients at trauma Level 1–2 hospitals had a 43% increased odds of preterm labor (95% CI: 1.15–1.79) and a 66% increased odds of meconium at delivery (95% CI: 1.05–2.61) compared to those treated at Level 3–4 hospitals. Patients with an injury severity score >9, treated at trauma Level 1–2 hospitals, had an aOR of low birth weight, <2500 g, of 2.52 (95% CI: 1.12–5.64). Conclusions: The majority of birth outcomes for injured patients had no association with hospitalization at a Level 1–2 compared to a Level 3–4 trauma center. PMID:28971027

The Potential of Adaptive Design in Animal Studies.

PubMed

Majid, Arshad; Bae, Ok-Nam; Redgrave, Jessica; Teare, Dawn; Ali, Ali; Zemke, Daniel

2015-10-12

Clinical trials are the backbone of medical research, and are often the last step in the development of new therapies for use in patients. Prior to human testing, however, preclinical studies using animal subjects are usually performed in order to provide initial data on the safety and effectiveness of prospective treatments. These studies can be costly and time consuming, and may also raise concerns about the ethical treatment of animals when potentially harmful procedures are involved. Adaptive design is a process by which the methods used in a study may be altered while it is being conducted in response to preliminary data or other new information. Adaptive design has been shown to be useful in reducing the time and costs associated with clinical trials, and may provide similar benefits in preclinical animal studies. The purpose of this review is to summarize various aspects of adaptive design and evaluate its potential for use in preclinical research.

The Potential of Adaptive Design in Animal Studies

PubMed Central

Majid, Arshad; Bae, Ok-Nam; Redgrave, Jessica; Teare, Dawn; Ali, Ali; Zemke, Daniel

2015-01-01

Clinical trials are the backbone of medical research, and are often the last step in the development of new therapies for use in patients. Prior to human testing, however, preclinical studies using animal subjects are usually performed in order to provide initial data on the safety and effectiveness of prospective treatments. These studies can be costly and time consuming, and may also raise concerns about the ethical treatment of animals when potentially harmful procedures are involved. Adaptive design is a process by which the methods used in a study may be altered while it is being conducted in response to preliminary data or other new information. Adaptive design has been shown to be useful in reducing the time and costs associated with clinical trials, and may provide similar benefits in preclinical animal studies. The purpose of this review is to summarize various aspects of adaptive design and evaluate its potential for use in preclinical research. PMID:26473839

Standard spacecraft economic analysis. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

Harris, E. D.; Large, J. P.

1976-01-01

A study of the comparative program costs associated with use of various standardized spacecraft for Air Force space test program missions to be flown on the space shuttle during the 1980-1990 time period is reviewed. The first phase of the study considered a variety of procurement mixes composed of existing or programmed NASA standard spacecraft designs and a Air Force standard spacecraft design. The results were briefed to a joint NASA/Air Force audience on July 11, 1976. The second phase considered additional procurement options using an upgraded version of an existing NASA design. The results of both phases are summarized.

Design and Development of the Solar Dynamics Observatory (SDO) Electrical Power System

NASA Technical Reports Server (NTRS)

Denney, Keys; Burns, Michael; Kercheval, Bradford

2009-01-01

The SDO spacecraft was designed to help us understand the Sun's influence on Earth and Near-Earth space by studying the solar atmosphere on small scales of space and time and in many wavelengths simultaneously. It will perform its operations in a geosynchronous orbit of the earth. This paper will present background on the SDO mission, an overview of the design and development activities associated specifically with the SDO electrical power system (EPS), as well as the major driving requirements behind the mission design. The primary coverage of the paper will be devoted to some of the challenges faced during the design and development phase. This will include the challenges associated with development of a compatible CompactPCI (cPCI) interface within the Power System Electronics (PSE) in order to utilize a "common" processor card, implementation of new solid state power controllers (SSPC) for primary load distribution switching and over current protection in the PSE, and the design approach adopted to meet single fault tolerance requirements for all of the SDO EPS functions.

Domestic incense use and lung cancer in Asia: a review.

PubMed

Seow, Wei Jie; Lan, Qing

2016-03-01

While there is strong evidence for the association between household air pollution and lung cancer among non-smoking women, the association between domestic incense use and lung cancer risk has been inconsistent. We conducted a systematic review of PubMed articles authored between 1969 and August 25, 2015 before performing a manual review of each study, and found a total of seven published studies on this topic. Most of the studies are case-control in design and did not further stratify by sex and smoking status. Of the seven studies, three reported positive associations, three reported null associations and one study found a negative association between incense use and lung cancer. Only one study reported estimates for non-smoking women. Future studies should be larger in sample size, stratify by both sex and smoking status in their analyses, and collect more detailed information on incense use in order to facilitate the understanding of the association between domestic incense use and lung cancer risk among non-smoking women in Asia.

Item generation and design testing of a questionnaire to assess degenerative joint disease-associated pain in cats.

PubMed

Zamprogno, Helia; Hansen, Bernie D; Bondell, Howard D; Sumrell, Andrea Thomson; Simpson, Wendy; Robertson, Ian D; Brown, James; Pease, Anthony P; Roe, Simon C; Hardie, Elizabeth M; Wheeler, Simon J; Lascelles, B Duncan X

2010-12-01

To determine the items (question topics) for a subjective instrument to assess degenerative joint disease (DJD)-associated chronic pain in cats and determine the instrument design most appropriate for use by cat owners. 100 randomly selected client-owned cats from 6 months to 20 years old. Cats were evaluated to determine degree of radiographic DJD and signs of pain throughout the skeletal system. Two groups were identified: high DJD pain and low DJD pain. Owner-answered questions about activity and signs of pain were compared between the 2 groups to define items relating to chronic DJD pain. Interviews with 45 cat owners were performed to generate items. Fifty-three cat owners who had not been involved in any other part of the study, 19 veterinarians, and 2 statisticians assessed 6 preliminary instrument designs. 22 cats were selected for each group; 19 important items were identified, resulting in 12 potential items for the instrument; and 3 additional items were identified from owner interviews. Owners and veterinarians selected a 5-point descriptive instrument design over 11-point or visual analogue scale formats. Behaviors relating to activity were substantially different between healthy cats and cats with signs of DJD-associated pain. Fifteen items were identified as being potentially useful, and the preferred instrument design was identified. This information could be used to construct an owner-based questionnaire to assess feline DJD-associated pain. Once validated, such a questionnaire would assist in evaluating potential analgesic treatments for these patients.

Antidepressant Exposure During Pregnancy and Risk of Autism in the Offspring, 2: Do the New Studies Add Anything New?

PubMed

Andrade, Chittaranjan

During the past year, at least 5 new studies, all observational in design, examined the risk of autism spectrum disorder (ASD) in children exposed to antidepressant medication in utero. These studies had not found inclusion in the many systematic reviews and meta-analyses that had also been published in the past year. Noteworthy methods and findings of the new studies are summarized. One of these studies is examined in detail to help the reader understand methodological and conceptual issues that are critical in the field. Some general caveats in the interpretation of the literature are also discussed. In order to reduce the limitations associated with their observational design, the new studies used many innovations, including maternal controls with mental illness, propensity score-matched controls, preconception antidepressant exposure controls, sibling controls, paternal antidepressant user controls, and modeling for the presence of an unknown confound. Two studies found an association between maternal antidepressant use during pregnancy and the risk of ASD in the offspring; these associations remained statistically significant even after covariate adjustments. The other 3 studies found that the significant association between antidepressant exposure and ASD risk was lost after statistical adjustment; that preconception antidepressant exposure was also associated with increased risk of ASD; that siblings discordant for antidepressant exposure had similar ASD risk; and that paternal antidepressant use was also associated with increased risk. The new studies do not change the conclusions of the available meta-analyses. In fact, at least some of the new data strengthen the conclusion that antidepressant use during pregnancy is likely to be a marker of more severe illness and that inadequately measured, unmeasured, or unknown genetic, behavioral, and environmental confounds associated with more severe illness (rather than the antidepressant exposure by itself) may be responsible for the increased risk of ASD. © Copyright 2017 Physicians Postgraduate Press, Inc.

Design of clinical trials evaluating dietary interventions in patients with functional gastrointestinal disorders.

PubMed

Yao, Chu K; Gibson, Peter R; Shepherd, Susan J

2013-05-01

Clear guiding principles for the design and conduct of dietary intervention trials in functional gastrointestinal disorders (FGID) are lacking. This narrative review examines the specific challenges associated with the design and reporting in dietary intervention trials. Dietary intervention trials need to address the collinearity between food, nutrients, and bioactive components that obscure the relationship between food and their effects in the gut. Randomized, double-blinded, placebo-controlled studies remain the gold standard for dietary trials, but are limited by difficulties in adequate masking of study food or inappropriate choice of placebo food/diets. Provision of study diets as the preferred delivery method can somewhat address these limitations, although allowing good adherence compared with education-based dietary interventions. Issues associated with participant expectancies and dietary behaviors can alter the true effectiveness of a diet. In addition, failure to adjust for or report baseline intake of nutrients of interest can reduce their magnitude of benefit. Bias in subjective reports and choice of measurement tools can preclude accurate assessment of food-intake data. In the design of elimination and rechallenge studies, sufficient time period and adequate exclusion of dietary triggers are essential to ensure symptoms are well-controlled before rechallenging. The route and frequency of challenging, design of test food, and/or placebo should match the aims of the rechallenge phase. Long-term efficacy data of such therapeutic diets has been poorly documented in most studies. Standardized guidelines that address many of the challenges outlined above are suggested to strengthen the quality of evidence for dietary therapies in FGID.

Personalized Risk Estimator for Rheumatoid Arthritis (PRE-RA) Family Study: Rationale and design for a randomized controlled trial evaluating rheumatoid arthritis risk education to first-degree relatives

PubMed Central

Sparks, Jeffrey A.; Iversen, Maura D.; Kroouze, Rachel Miller; Mahmoud, Taysir G.; Triedman, Nellie A.; Kalia, Sarah S.; Atkinson, Michael L.; Lu, Bing; Deane, Kevin D.; Costenbader, Karen H.; Green, Robert C.; Karlson, Elizabeth W.

2014-01-01

We present the rationale, design features, and protocol of the Personalized Risk Estimator for Rheumatoid Arthritis (PRE-RA) Family Study (ClinicalTrials.gov NCT02046005). The PRE-RA Family Study is an NIH-funded prospective, randomized controlled trial designed to compare the willingness to change behaviors in first-degree relatives of rheumatoid arthritis (RA) patients without RA after exposure to RA risk educational programs. Consented subjects are randomized to receive education concerning their personalized RA risk based on demographics, RA-associated behaviors, genetics and biomarkers or to receive standard RA information. Four behavioral factors associated with RA risk were identified from prior studies for inclusion in the risk estimate: cigarette smoking, excess body weight, poor oral health, and low fish intake. Personalized RA risk information is presented through an online tool that collects data on an individual's specific age, gender, family history, and risk-related behaviors; presents genetic and biomarker results; displays relative and absolute risk of RA; and provides personalized feedback and education. The trial outcomes will be changes in willingness to alter behaviors from baseline to 6 weeks, 6 months, and 12 months in the three intervention groups. The design and execution of this trial that targets a special population at risk for RA, while incorporating varied risk factors into a single risk tool, offer distinct challenges. We provide the theoretical rationale for the PRE-RA Family Study and highlight particular design features of this trial that utilize personalized risk education as an intervention. PMID:25151341

Packed red blood cell transfusion is not associated with increased risk of necrotizing enterocolitis in premature infants

PubMed Central

Sharma, R; Kraemer, DF; Torrazza, RM; Mai, V; Neu, J; Shuster, JJ; Hudak, ML

2015-01-01

OBJECTIVE Recent reports have posited a temporal association between blood transfusion with packed red blood cells (BT) and necrotizing enterocolitis (NEC). We evaluated the relationship between BT and NEC among infants at three hospitals who were consented at birth into a prospective observational study of NEC. STUDY DESIGN We used a case–control design to match each case of NEC in our study population of infants born at <33 weeks postmenstrual age (PMA) to one control infant using hospital of birth, PMA, birth weight and date of birth. RESULT The number of transfusions per infant did not differ between 42 NEC cases and their controls (4.0 ± 4.6 vs 5.4 ± 4.1, mean ± s.d., P = 0.063). A matched-pair analysis did not identify an association of transfusion with NEC in either the 48-h or 7-day time periods before the onset of NEC. Stratifying on matched-sets, the Cox proportional hazard model did not identify any difference in the total number of BTs between the two groups (hazard ratio 0.78, 95% confidence interval 0.57 to 1.07, P = 0.11). CONCLUSION In contrast to previous studies, our case–control study did not identify a significant temporal association between BT and NEC. Additional large prospective randomized studies are needed to clarify the relationship between BT and NEC. PMID:25144159

Association between molecular markers and behavioral phenotypes in the immatures of a butterfly.

PubMed

De Nardin, Janaína; Buffon, Vanessa; Revers, Luís Fernando; de Araújo, Aldo Mellender

2018-01-01

Newly hatched caterpillars of the butterfly Heliconius erato phyllis routinely cannibalize eggs. In a manifestation of kin recognition they cannibalize sibling eggs less frequently than unrelated eggs. Previous work has estimated the heritability of kin recognition in H. erato phyllis to lie between 14 and 48%. It has furthermore been shown that the inheritance of kin recognition is compatible with a quantitative model with a threshold. Here we present the results of a preliminary study, in which we tested for associations between behavioral kin recognition phenotypes and AFLP and SSR markers. We implemented two experimental approaches: (1) a cannibalism test using sibling eggs only, which allowed for only two behavioral outcomes (cannibal and non-cannibal), and (2) a cannibalism test using two sibling eggs and one unrelated egg, which allowed four outcomes [cannibal who does not recognize siblings, cannibal who recognizes siblings, "super-cannibal" (cannibal of both eggs), and "super non-cannibal" (does not cannibalize eggs at all)]. Single-marker analyses were performed using χ2 tests and logistic regression with null markers as covariates. Results of the χ2 tests identified 72 associations for experimental design 1 and 73 associations for design 2. Logistic regression analysis of the markers found to be significant in the χ2 test resulted in 20 associations for design 1 and 11 associations for design 2. Experiment 2 identified markers that were more frequently present or absent in cannibals who recognize siblings and super non-cannibals; i.e. in both phenotypes capable of kin recognition.

Association between molecular markers and behavioral phenotypes in the immatures of a butterfly

PubMed Central

De Nardin, Janaína; Buffon, Vanessa; Revers, Luís Fernando; de Araújo, Aldo Mellender

2018-01-01

Abstract Newly hatched caterpillars of the butterfly Heliconius erato phyllis routinely cannibalize eggs. In a manifestation of kin recognition they cannibalize sibling eggs less frequently than unrelated eggs. Previous work has estimated the heritability of kin recognition in H. erato phyllis to lie between 14 and 48%. It has furthermore been shown that the inheritance of kin recognition is compatible with a quantitative model with a threshold. Here we present the results of a preliminary study, in which we tested for associations between behavioral kin recognition phenotypes and AFLP and SSR markers. We implemented two experimental approaches: (1) a cannibalism test using sibling eggs only, which allowed for only two behavioral outcomes (cannibal and non-cannibal), and (2) a cannibalism test using two sibling eggs and one unrelated egg, which allowed four outcomes [cannibal who does not recognize siblings, cannibal who recognizes siblings, “super-cannibal” (cannibal of both eggs), and “super non-cannibal” (does not cannibalize eggs at all)]. Single-marker analyses were performed using χ2 tests and logistic regression with null markers as covariates. Results of the χ2 tests identified 72 associations for experimental design 1 and 73 associations for design 2. Logistic regression analysis of the markers found to be significant in the χ2 test resulted in 20 associations for design 1 and 11 associations for design 2. Experiment 2 identified markers that were more frequently present or absent in cannibals who recognize siblings and super non-cannibals; i.e. in both phenotypes capable of kin recognition. PMID:29583155

Acculturation, Medication Adherence, Lifestyle Behaviors, and Blood Pressure Control Among Arab Americans.

PubMed

Tailakh, Ayman K; Evangelista, Lorraine S; Morisky, Donald E; Mentes, Janet C; Pike, Nancy A; Phillips, Linda R

2016-01-01

The aim of this study was to examine the relationship between acculturation, medication adherence, lifestyle behaviors (e.g., physical activity, nutrition, weight control), and blood pressure control among hypertensive Arab Americans. The study utilized a cross-sectional descriptive design. A convenience sample of 126 participants completed questionnaires and had measures of blood pressure, weight, and height. Forty-six participants were hypertensive and were included in the analysis. Only 29.2% of participants reported high medication adherence. High medication adherence was associated with lower diastolic blood pressure, eating a healthy diet, and following lifestyle modifications. Acculturation was significantly associated with physical activity and body mass index. Our study found that acculturated participants were more adherent to medications and physical activity and had better blood pressure control. Further studies are needed to explore how acculturation improves adherence and what factors contribute to better adherence in order to design culturally sensitive interventions. © The Author(s) 2014.

Towards a general object-oriented software development methodology

NASA Technical Reports Server (NTRS)

Seidewitz, ED; Stark, Mike

1986-01-01

Object diagrams were used to design a 5000 statement team training exercise and to design the entire dynamics simulator. The object diagrams are also being used to design another 50,000 statement Ada system and a personal computer based system that will be written in Modula II. The design methodology evolves out of these experiences as well as the limitations of other methods that were studied. Object diagrams, abstraction analysis, and associated principles provide a unified framework which encompasses concepts from Yourdin, Booch, and Cherry. This general object-oriented approach handles high level system design, possibly with concurrency, through object-oriented decomposition down to a completely functional level. How object-oriented concepts can be used in other phases of the software life-cycle, such as specification and testing is being studied concurrently.

Expert Recommender: Designing for a Network Organization

NASA Astrophysics Data System (ADS)

Reichling, Tim; Veith, Michael; Wulf, Volker

Recent knowledge management initiatives focus on expertise sharing within formal organizational units and informal communities of practice. Expert recommender systems seem to be a promising tool in support of these initiatives. This paper presents experiences in designing an expert recommender system for a knowledge- intensive organization, namely the National Industry Association (NIA). Field study results provide a set of specific design requirements. Based on these requirements, we have designed an expert recommender system which is integrated into the specific software infrastructure of the organizational setting. The organizational setting is, as we will show, specific for historical, political, and economic reasons. These particularities influence the employees’ organizational and (inter-)personal needs within this setting. The paper connects empirical findings of a long-term case study with design experiences of an expertise recommender system.

Association Between Periodontal Disease and Erectile Dysfunction: A Systematic Review

PubMed Central

Kellesarian, Sergio Varela; Kellesarian, Tammy Varela; Ros Malignaggi, Vanessa; Al-Askar, Mansour; Ghanem, Alexis; Malmstrom, Hans; Javed, Fawad

2016-01-01

A limited number of studies have reported an association between erectile dysfunction (ED) and chronic periodontitis (CP). The aim of the present study is to assess the association between CP and ED through a systematic review of published literature. To address the focused question, “Is there a relationship between ED and CP?” indexed databases were searched till December 2015 using various key words “erectile dysfunction,” “periodontal disease,” “periodontitis,” “dental infection,” and “impotence.” Letters to the editor, commentaries, historic reviews, and experimental studies were excluded. The pattern of the present systematic review was customized to primarily summarize the pertinent data. Nine studies were included. Seven studies had a cross-sectional design and two studies were randomized control trials. The number of study participants ranged between 53 and 513,258 individuals with age ranging between 20 years and 85 years (median age ranging between 34.9 ± 4.9 years and 50.9 ± 16.6 years). In all studies, a positive relationship between CP and ED was reported. In four studies, odds ratio were reported, ranging between 1.53 and 3.35. From the literature reviewed, there seems to be a positive association between ED and CP; however, further well-designed controlled clinical trials are needed in this regard. It is emphasized that physicians should refer patients with ED to oral health care providers for a comprehensive oral evaluation and treatment. PMID:27030114

Compliance with recommended care at trauma centers: association with patient outcomes.

PubMed

Shafi, Shahid; Barnes, Sunni A; Rayan, Nadine; Kudyakov, Rustam; Foreman, Michael; Cryer, H Gil; Alam, Hasan B; Hoff, William; Holcomb, John

2014-08-01

State health departments and the American College of Surgeons focus on the availability of optimal resources to designate hospitals as trauma centers, with little emphasis on actual delivery of care. There is no systematic information on clinical practices at designated trauma centers. The objective of this study was to measure compliance with 22 commonly recommended clinical practices at trauma centers and its association with in-hospital mortality. This retrospective observational study was conducted at 5 Level I trauma centers across the country. Participants were adult patients with moderate to severe injuries (n = 3,867). The association between compliance with 22 commonly recommended clinical practices and in-hospital mortality was measured after adjusting for patient demographics and injuries and their severity. Compliance with individual clinical practices ranged from as low as 12% to as high as 94%. After adjusting for patient demographics and injury severity, each 10% increase in compliance with recommended care was associated with a 14% reduction in the risk of death. Patients who received all recommended care were 58% less likely to die (odds ratio = 0.42; 95% CI, 0.28-0.62) compared with those who did not. Compliance with commonly recommended clinical practices remains suboptimal at designated trauma centers. Improved adoption of these practices can reduce mortality. Copyright © 2014 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Estrogen treatment effects on cognition, memory and mood in male-to-female transsexuals.

PubMed

Miles, Clare; Green, Richard; Hines, Melissa

2006-12-01

Gonadal hormones, particularly estrogens, have been suggested to influence memory and cognitive tasks that show sex differences. Previously, we reported that male-to-female (M-F) transsexuals undergoing estrogen treatment for sex re-assignment scored higher on verbal Paired Associate Learning (PAL) than a transsexual control group awaiting estrogen treatment. The present study used a more robust design to examine further associations between estrogen and cognition. We assessed additional aspects of memory, including visual, spatial, object and location memory, other cognitive abilities that show reliable sex differences, including verbal and visual-spatial abilities, and mood variables that could mediate associations between estrogen and cognition. In addition to comparing groups of individuals on and off estrogen, we used two repeated measures designs (AB and BA). The AB group was tested prior to hormone treatment and then again after treatment had begun; the BA group was tested while on estrogen treatment and then again when hormones had been withdrawn prior to surgery. Few changes in memory or cognition were observed, and changes that were observed were not consistent across study designs. The lack of significant effects did not relate to mood changes or to the sexual orientation of participants. These findings suggest that estrogen treatment associated with sex change for M-F transsexuals has little or no influence on sex-typed aspects of cognition or memory.

The Power to Detect Linkage Disequilibrium with Quantitative Traits in Selected Samples

PubMed Central

Abecasis, Gonçalo R.; Cookson, William O. C.; Cardon, Lon R.

2001-01-01

Results from power studies for linkage detection have led to many ongoing and planned collections of phenotypically extreme nuclear families. Given the great expense of collecting these families and the imminent availability of a dense diallelic marker map, the families are likely to be used in allelic-association as well as linkage studies. However, optimal selection strategies for linkage may not be equally powerful for association. We examine the power to detect linkage disequilibrium for quantitative traits after phenotypic selection. The results encompass six selection strategies that are in widespread use, including single selection (two designs), affected sib pairs, concordant and discordant pairs, and the extreme-concordant and -discordant design. Selection of sibships on the basis of one extreme proband with high or low trait scores provides as much power as discordant sib pairs but requires the screening and phenotyping of substantially fewer initial families from which to select. Analysis of the role of allele frequencies within each selection design indicates that common trait alleles generally offer the most power, but similarities between the marker- and trait-allele frequencies are much more important than the trait-locus frequency alone. Some of the most widespread selection designs, such as single selection, yield power gains only when both the marker and quantitative trait loci (QTL) are relatively rare in the population. In contrast, discordant pairs and the extreme-proband design provide power for the broadest range of QTL–marker-allele frequency differences. Overall, proband selection from either tail provides the best balance of power, robustness, and simplicity of ascertainment for family-based association analysis. PMID:11349228

Factors associated with smoking in Asian American adults: a systematic review.

PubMed

Zhang, Jing; Wang, Zhongmiao

2008-05-01

This review systematically examined the factors associated with smoking in Asian American adults (aged > or =17 years). A total of 21 quantitative studies published in peer-reviewed journals from 1997 to 2006 were reviewed and abstracted using the matrix method. Statistically significant factors reported by the studies were summarized. Methodological quality of the studies also was assessed (maximum possible score = 10). Acculturation and education were the most frequently reported factors (n = 10, 47.6%). Acculturation was negatively associated with men's smoking but was positively associated with women's smoking. Education was uniformly found to be negatively related to smoking. Age was reported to have either a positive or a negative relationship with smoking (n = 9, 42.9%). Men were more likely to smoke than women (n = 7, 33.3%). The mean methodological score of the reviewed studies was 4.14 (on a scale of 1-10 points; SD = 1.62; range = 2-8). Health promotion professionals need to consider the summarized factors associated with Asian American adults' smoking behavior when planning smoking prevention programs and when recruiting participants for smoking cessation programs. When addressing acculturation, program planners should design different health education materials and use different strategies for men and women. To identify, understand, and incorporate essential factors into effective interventions, future studies should aim at higher methodological quality by using longitudinal design and increasing the use of theory, the test of data validity and reliability, and the report of effect sizes.

Early life adversity and telomere length: a meta-analysis.

PubMed

Ridout, K K; Levandowski, M; Ridout, S J; Gantz, L; Goonan, K; Palermo, D; Price, L H; Tyrka, A R

2018-04-01

Early adversity, in the form of abuse, neglect, socioeconomic status and other adverse experiences, is associated with poor physical and mental health outcomes. To understand the biologic mechanisms underlying these associations, studies have evaluated the relationship between early adversity and telomere length, a marker of cellular senescence. Such results have varied in regard to the size and significance of this relationship. Using meta-analytic techniques, we aimed to clarify the relationship between early adversity and telomere length while exploring factors affecting the association, including adversity type, timing and study design. A comprehensive search in July 2016 of PubMed/MEDLINE, PsycINFO and Web of Science identified 2462 studies. Multiple reviewers appraised studies for inclusion or exclusion using a priori criteria; 3.9% met inclusion criteria. Data were extracted into a structured form; the Newcastle-Ottawa Scale assessed study quality, validity and bias. Forty-one studies (N=30 773) met inclusion criteria. Early adversity and telomere length were significantly associated (Cohen's d effect size=-0.35; 95% CI, -0.46 to -0.24; P<0.0001). Sensitivity analyses revealed no outlier effects. Adversity type and timing significantly impacted the association with telomere length (P<0.0001 and P=0.0025, respectively). Subgroup and meta-regression analyses revealed that medication use, medical or psychiatric conditions, case-control vs longitudinal study design, methodological factors, age and smoking significantly affected the relationship. Comprehensive evaluations of adversity demonstrated more extensive telomere length changes. These results suggest that early adversity may have long-lasting physiological consequences contributing to disease risk and biological aging.

Association of Cryoprecipitate and Tranexamic Acid with Improved Survival Following Wartime Injury: Findings from the MATTERs II Study

DTIC Science & Technology

2012-11-19

ONLINE FIRST ORIGINAL ARTICLE Association of Cryoprecipitate and Tranexamic Acid With Improved Survival Following Wartime Injury Findings From the... tranexamic acid on survival in combat injured. Design: Retrospective observational study comparing the mortalityof4groups: tranexamicacidonly...and com- posed the following groups: tranexamic acid (n=148), cryoprecipitate (n=168), tranexamic acid /cryoprecipi- tate (n=258), and no tranexamic

Does Metformin Reduce Cancer Risks? Methodologic Considerations.

PubMed

Golozar, Asieh; Liu, Shuiqing; Lin, Joeseph A; Peairs, Kimberly; Yeh, Hsin-Chieh

2016-01-01

The substantial burden of cancer and diabetes and the association between the two conditions has been a motivation for researchers to look for targeted strategies that can simultaneously affect both diseases and reduce their overlapping burden. In the absence of randomized clinical trials, researchers have taken advantage of the availability and richness of administrative databases and electronic medical records to investigate the effects of drugs on cancer risk among diabetic individuals. The majority of these studies suggest that metformin could potentially reduce cancer risk. However, the validity of this purported reduction in cancer risk is limited by several methodological flaws either in the study design or in the analysis. Whether metformin use decreases cancer risk relies heavily on the availability of valid data sources with complete information on confounders, accurate assessment of drug use, appropriate study design, and robust analytical techniques. The majority of the observational studies assessing the association between metformin and cancer risk suffer from methodological shortcomings and efforts to address these issues have been incomplete. Future investigations on the association between metformin and cancer risk should clearly address the methodological issues due to confounding by indication, prevalent user bias, and time-related biases. Although the proposed strategies do not guarantee a bias-free estimate for the association between metformin and cancer, they will reduce synthesis of and reporting of erroneous results.

The Impact of Short-Term Professional Development on Participant Outcomes: A Review of the Literature

ERIC Educational Resources Information Center

Lauer, Patricia A.; Christopher, Debra E.; Firpo-Triplett, Regina; Buchting, Francisco

2014-01-01

A narrative literature review was conducted to identify the design features of effective short-term face-to-face professional development (PD) events. The 23 reviewed studies described PD with durations of 30 hours or less and involved participants in education or human service-related professions. Design features associated with positive impacts…

A Student-Constructed Test Learning System: The Design, Development and Evaluation of Its Pedagogical Potential

ERIC Educational Resources Information Center

Yu, Fu-Yun; Su, Chia-Ling

2015-01-01

Although research has found that student-constructed tests (SCT) have some potential for promoting cognitive elaboration, as yet there are no systems available to support the associated activities. This study designed and developed an SCT learning system guided by the ideology of contribution-based pedagogies, accentuating the principles of…

Grid-Optimization Program for Photovoltaic Cells

NASA Technical Reports Server (NTRS)

Daniel, R. E.; Lee, T. S.

1986-01-01

CELLOPT program developed to assist in designing grid pattern of current-conducting material on photovoltaic cell. Analyzes parasitic resistance losses and shadow loss associated with metallized grid pattern on both round and rectangular solar cells. Though performs sensitivity studies, used primarily to optimize grid design in terms of bus bar and grid lines by minimizing power loss. CELLOPT written in APL.

Organizational and Individual Conditions Associated with Depressive Symptoms among Nursing Home Residents over Time

ERIC Educational Resources Information Center

Cassie, Kimberly M.; Cassie, William E.

2012-01-01

Purpose: To examine the effect of organizational culture and climate on depressive symptoms among nursing home residents. Design and Methods: Using a pooled cross-sectional design, this study examines a sample of 23 nursing homes, 1,114 employees, and 5,497 residents. Depressive symptoms were measured using the Minimum Data Set, Depression Rating…

Impact of Adult Day Services on Behavioral and Psychological Symptoms of Dementia

ERIC Educational Resources Information Center

Femia, Elia E.; Zarit, Steven H.; Stephens, Mary Ann Parris; Greene, Rick

2007-01-01

Purpose: This study explored whether adult day service (ADS) use was associated with reductions in behavioral and psychological symptoms of dementia (BPSD) in individuals with dementia. Design and Methods: We used a quasi-experimental design to compare a group of 133 persons with dementia (PWDs) who initially enrolled in an ADS program to a…

Elementary Anatomy: Activities Designed to Teach Preschool Children about the Human Body

ERIC Educational Resources Information Center

Raven, Sara

2016-01-01

Studies show that children may not be able to conceptualize some of the topics associated with anatomy, including internal organs and involuntary muscles, because the concepts are too abstract and are not easily visualized. Thus, this article presents activities that incorporate a variety of models and hands-on activities designed to provide…

Applying Quality Indicators to Single-Case Research Designs Used in Special Education: A Systematic Review

ERIC Educational Resources Information Center

Moeller, Jeremy D.; Dattilo, John; Rusch, Frank

2015-01-01

This study examined how specific guidelines and heuristics have been used to identify methodological rigor associated with single-case research designs based on quality indicators developed by Horner et al. Specifically, this article describes how literature reviews have applied Horner et al.'s quality indicators and evidence-based criteria.…

American Association of University Women: Branch Operations Data Modeling Case

ERIC Educational Resources Information Center

Harris, Ranida B.; Wedel, Thomas L.

2015-01-01

A nationally prominent woman's advocacy organization is featured in this case study. The scenario may be used as a teaching case, an assignment, or a project in systems analysis and design as well as database design classes. Students are required to document the system operations and requirements, apply logical data modeling concepts, and design…

A study of space station needs, attributes and architectural options. Final briefing: Cost working group discussion session

NASA Technical Reports Server (NTRS)

1983-01-01

The economic factors involved in the design and utilization of the space station are investigated. Topics include the economic benefits associated with research and production, the orbit transfer vehicle, and satellite servicing. Program costs and design options are examined. The possibilities of financing from the private sector are discussed.

Quantitative Relationship Between Cumulative Risk Alleles Based on Genome-Wide Association Studies and Type 2 Diabetes Mellitus: A Systematic Review and Meta-analysis.

PubMed

Kodama, Satoru; Fujihara, Kazuya; Ishiguro, Hajime; Horikawa, Chika; Ohara, Nobumasa; Yachi, Yoko; Tanaka, Shiro; Shimano, Hitoshi; Kato, Kiminori; Hanyu, Osamu; Sone, Hirohito

2018-01-05

Many epidemiological studies have assessed the genetic risk of having undiagnosed or of developing type 2 diabetes mellitus (T2DM) using several single nucleotide polymorphisms (SNPs) based on findings of genome-wide association studies (GWAS). However, the quantitative association of cumulative risk alleles (RAs) of such SNPs with T2DM risk has been unclear. The aim of this meta-analysis is to review the strength of the association between cumulative RAs and T2DM risk. Systematic literature searches were conducted for cross-sectional or longitudinal studies that examined odds ratios (ORs) for T2DM in relation to genetic profiles. Logarithm of the estimated OR (log OR) of T2DM for 1 increment in RAs carried (1-ΔRA) in each study was pooled using a random-effects model. There were 46 eligible studies that included 74,880 cases among 249,365 participants. In 32 studies with a cross-sectional design, the pooled OR for T2DM morbidity for 1-ΔRA was 1.16 (95% confidence interval [CI], 1.13-1.19). In 15 studies that had a longitudinal design, the OR for incident T2DM was 1.10 (95% CI, 1.08-1.13). There was large heterogeneity in the magnitude of log OR (P < 0.001 for both cross-sectional studies and longitudinal studies). The top 10 commonly used genes significantly explained the variance in the log OR (P = 0.04 for cross-sectional studies; P = 0.006 for longitudinal studies). The current meta-analysis indicated that carrying 1-ΔRA in T2DM-associated SNPs was associated with a modest risk of prevalent or incident T2DM, although the heterogeneity in the used genes among studies requires us to interpret the results with caution.

Quantitative Relationship Between Cumulative Risk Alleles Based on Genome-Wide Association Studies and Type 2 Diabetes Mellitus: A Systematic Review and Meta-analysis

PubMed Central

Kodama, Satoru; Fujihara, Kazuya; Ishiguro, Hajime; Horikawa, Chika; Ohara, Nobumasa; Yachi, Yoko; Tanaka, Shiro; Shimano, Hitoshi; Kato, Kiminori; Hanyu, Osamu; Sone, Hirohito

2018-01-01

Many epidemiological studies have assessed the genetic risk of having undiagnosed or of developing type 2 diabetes mellitus (T2DM) using several single nucleotide polymorphisms (SNPs) based on findings of genome-wide association studies (GWAS). However, the quantitative association of cumulative risk alleles (RAs) of such SNPs with T2DM risk has been unclear. The aim of this meta-analysis is to review the strength of the association between cumulative RAs and T2DM risk. Systematic literature searches were conducted for cross-sectional or longitudinal studies that examined odds ratios (ORs) for T2DM in relation to genetic profiles. Logarithm of the estimated OR (log OR) of T2DM for 1 increment in RAs carried (1-ΔRA) in each study was pooled using a random-effects model. There were 46 eligible studies that included 74,880 cases among 249,365 participants. In 32 studies with a cross-sectional design, the pooled OR for T2DM morbidity for 1-ΔRA was 1.16 (95% confidence interval [CI], 1.13–1.19). In 15 studies that had a longitudinal design, the OR for incident T2DM was 1.10 (95% CI, 1.08–1.13). There was large heterogeneity in the magnitude of log OR (P < 0.001 for both cross-sectional studies and longitudinal studies). The top 10 commonly used genes significantly explained the variance in the log OR (P = 0.04 for cross-sectional studies; P = 0.006 for longitudinal studies). The current meta-analysis indicated that carrying 1-ΔRA in T2DM-associated SNPs was associated with a modest risk of prevalent or incident T2DM, although the heterogeneity in the used genes among studies requires us to interpret the results with caution. PMID:29093303

Clinical and pharmacogenomic data mining: 2. A simple method for the combination of information from associations and multivariances to facilitate analysis, decision, and design in clinical research and practice.

PubMed

Robson, Barry; Mushlin, Richard

2004-01-01

The physician and researcher must ultimately be able to combine qualitative and quantitative features from a variety of combinations of observations on data of many component items (i.e., many dimensions), and hence reach simple conclusions about interpretation, rational courses of action, and design. In the first paper of this series, it was noted that such needs are challenging the classical means of using statistics. Hence, the paper proposed the use of a Generalized Theory of Expected Information or "Zeta Theory". The conjoint event [a,b,c,..] is seen as a rule of association for a,b,c,.. associated with a rule strength I(a;b;c;...) = xi(s,o[a,b,c,..]) - xi (s,e[a,b,c,...]), where xi is the incomplete Zeta Function. Here, o[a,b,c,...] is the observed, and e[a,b,c,..] the expected, frequency of occurrence of conjoint event [a,b,c,...]. The present paper explores how output from this approach might be assembled in a form better suited for decision support. Related to this is the difficulty that the treatment of covariance and multivariance was previously rendered as a "fuzzy association" so that the output would fall into a similar form as the true associations, but this was a somewhat ad hoc approach in which only the final I( ) had any meaning. Users at clinical research sites had subsequently requested an alternative approach in which "effective frequencies" o[ ] and e[ ] calculated from the above variances and used to evaluate I( ) give some intuitive feeling analogous to the association treatment, and this is explored here. Though the present paper is theoretical, real examples are used to illustrate application. One clinical-genomic example illustrates experimental design by identifying data which is, or is not, statistically germane to the study. We also report on some impressions based on applying these techniques in studies of real, extensive patient record data which are now emerging, as well as on molecular design data originally studied in part to test the ability to deduce the effects of simple natural patient sequence variations ("SNPs") on patient protein activity. On the basis of these study experiences, methods of rationalizing and condensing the rules implied by associations and variances between data, as well as discussion of the difficulty of what is meant by "condensed", are presented in the Appendix.

Association between the 2008-09 seasonal influenza vaccine and pandemic H1N1 illness during Spring-Summer 2009: four observational studies from Canada.

PubMed

Skowronski, Danuta M; De Serres, Gaston; Crowcroft, Natasha S; Janjua, Naveed Z; Boulianne, Nicole; Hottes, Travis S; Rosella, Laura C; Dickinson, James A; Gilca, Rodica; Sethi, Pam; Ouhoummane, Najwa; Willison, Donald J; Rouleau, Isabelle; Petric, Martin; Fonseca, Kevin; Drews, Steven J; Rebbapragada, Anuradha; Charest, Hugues; Hamelin, Marie-Eve; Boivin, Guy; Gardy, Jennifer L; Li, Yan; Kwindt, Trijntje L; Patrick, David M; Brunham, Robert C

2010-04-06

In late spring 2009, concern was raised in Canada that prior vaccination with the 2008-09 trivalent inactivated influenza vaccine (TIV) was associated with increased risk of pandemic influenza A (H1N1) (pH1N1) illness. Several epidemiologic investigations were conducted through the summer to assess this putative association. (1) test-negative case-control design based on Canada's sentinel vaccine effectiveness monitoring system in British Columbia, Alberta, Ontario, and Quebec; (2) conventional case-control design using population controls in Quebec; (3) test-negative case-control design in Ontario; and (4) prospective household transmission (cohort) study in Quebec. Logistic regression was used to estimate odds ratios for TIV effect on community- or hospital-based laboratory-confirmed seasonal or pH1N1 influenza cases compared to controls with restriction, stratification, and adjustment for covariates including combinations of age, sex, comorbidity, timeliness of medical visit, prior physician visits, and/or health care worker (HCW) status. For the prospective study risk ratios were computed. Based on the sentinel study of 672 cases and 857 controls, 2008-09 TIV was associated with statistically significant protection against seasonal influenza (odds ratio 0.44, 95% CI 0.33-0.59). In contrast, estimates from the sentinel and three other observational studies, involving a total of 1,226 laboratory-confirmed pH1N1 cases and 1,505 controls, indicated that prior receipt of 2008-09 TIV was associated with increased risk of medically attended pH1N1 illness during the spring-summer 2009, with estimated risk or odds ratios ranging from 1.4 to 2.5. Risk of pH1N1 hospitalization was not further increased among vaccinated people when comparing hospitalized to community cases. Prior receipt of 2008-09 TIV was associated with increased risk of medically attended pH1N1 illness during the spring-summer 2009 in Canada. The occurrence of bias (selection, information) or confounding cannot be ruled out. Further experimental and epidemiological assessment is warranted. Possible biological mechanisms and immunoepidemiologic implications are considered.

Associations between Intimate Partner Violence and Termination of Pregnancy: A Systematic Review and Meta-Analysis

PubMed Central

Hall, Megan; Chappell, Lucy C.; Parnell, Bethany L.; Seed, Paul T.; Bewley, Susan

2014-01-01

Background Intimate partner violence (IPV) and termination of pregnancy (TOP) are global health concerns, but their interaction is undetermined. The aim of this study was to determine whether there is an association between IPV and TOP. Methods and Findings A systematic review based on a search of Medline, Embase, PsycINFO, and Ovid Maternity and Infant Care from each database's inception to 21 September 2013 for peer-reviewed articles of any design and language found 74 studies regarding women who had undergone TOP and had experienced at least one domain (physical, sexual, or emotional) of IPV. Prevalence of IPV and association between IPV and TOP were meta-analysed. Sample sizes ranged from eight to 33,385 participants. Worldwide, rates of IPV in the preceding year in women undergoing TOP ranged from 2.5% to 30%. Lifetime prevalence by meta-analysis was shown to be 24.9% (95% CI 19.9% to 30.6%); heterogeneity was high (I 2>90%), and variation was not explained by study design, quality, or size, or country gross national income per capita. IPV, including history of rape, sexual assault, contraceptive sabotage, and coerced decision-making, was associated with TOP, and with repeat TOPs. By meta-analysis, partner not knowing about the TOP was shown to be significantly associated with IPV (pooled odds ratio 2.97, 95% CI 2.39 to 3.69). Women in violent relationships were more likely to have concealed the TOP from their partner than those who were not. Demographic factors including age, ethnicity, education, marital status, income, employment, and drug and alcohol use showed no strong or consistent mediating effect. Few long-term outcomes were studied. Women welcomed the opportunity to disclose IPV and be offered help. Limitations include study heterogeneity, potential underreporting of both IPV and TOP in primary data sources, and inherent difficulties in validation. Conclusions IPV is associated with TOP. Novel public health approaches are required to prevent IPV. TOP services provide an opportune health-based setting to design and test interventions. Please see later in the article for the Editors' Summary PMID:24409101

Relationship between QT Interval Dispersion in acute stroke and stroke prognosis: A Systematic Review

PubMed Central

Lederman, Yitzchok S.; Balucani, Clotilde; Lazar, Jason; Steinberg, Leah; Gugger, James; Levine, Steven R.

2014-01-01

Background QT dispersion (QTd) has been proposed as an indirect ECG measure of heterogeneity of ventricular repolarization. The predictive value of QTd in acute stroke remains controversial. We aimed to clarify the relationship between QTd and acute stroke and stroke prognosis. Methods A systematic review of the literature was performed using pre-specified medical subjects heading (MeSH) terms, Boolean logic and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Eligible studies (a) included ischemic or hemorrhagic stroke and (b) provided QTd measurements. Results Two independent reviewers identified 553 publications. Sixteen articles were included in the final analysis. There were a total of 888 stroke patients: 59% ischemic and 41% hemorrhagic. There was considerable heterogeneity in study design, stroke subtypes, ECG assessment-time, control groups and comparison groups. Nine studies reported a significant association between acute stroke and baseline QTd. Two studies reported that QTd increases are specifically related to hemorrhagic strokes, involvement of the insular cortex, right-side lesions, larger strokes, and increases in 3, 4-dihydroxyphenylethylene glycol in hemorrhagic stroke. Three studies reported QTd to be an independent predictor of stroke mortality. One study each reported increases in QTd in stroke patients who developed ventricular arrhythmias and cardiorespiratory compromise. Conclusions There are few well-designed studies and considerable variability in study design in addressing the significance of QTd in acute stroke. Available data suggest that stroke is likely to be associated with increased QTd. While some evidence suggests a possible prognostic role of QTd in stroke, larger and well-designed studies need to confirm these findings. PMID:25282188

Is gender still a predisposing factor in contrast-media associated adverse drug reactions? A systematic review and meta-analysis of randomized trials and observational studies.

PubMed

Lee, Heeyoung; Song, Seungyeon; Oh, Yun-Kyoung; Kang, WonKu; Kim, Eunyoung

2017-04-01

To evaluate the role of gender as a risk factor for developing contrast media-associated adverse drug reactions (CM-ADRs) by comparing the incidence of CM-ADR between male and female patients according to study design, ADR type, and computed tomography (CT) examination. We systematically searched three electronic databases for eligible studies. In the studies included (n=18), we assessed effect estimates of the relative incidence of CM-ADR, analysed by experimental design, ADR type and CT examination. This was calculated by using a random effects model if clinical conditions showed heterogeneity; otherwise, a fixed effects model was used. We identified 10,776 patients administered CM. According to the designs, studies were classified into randomised controlled trials (RCTs) and observational studies. Results were as follows: risk ratio (RR)=1.07 (95% confidence interval (CI): 0.79-1.46, P=0.66) for RCTs, and RR=0.77 (95% CI: 0.58-1.04, P=0.09) for observational studies. The results of analysis according to ADR type and for undergoing CT demonstrated that the incidence of CM-ADR did not differ between males and females. We found no significant difference in the incidence of CM-ADRs between male and female patients according to study design, ADR type, or CT examination. Future studies to determine why gender has shown different roles as a risk factor between CM-ADRs and non-CM ADRs are needed. Copyright © 2017 Elsevier B.V. All rights reserved.

Intestinal lymphangiectasia associated with recurrence of histiocytosis X.

PubMed

Hui, C K

2011-09-01

Intestinal lymphangiectasia may occur as a primary congenital disorder or a secondary disorder. Secondary lymphangiectasia could be associated with diseases such as abdominal carcinoma, retroperitoneal fibrosis or chronic pancreatitis. This is the first reported case of intestinal lymphangiectasia associated with recurrent histiocytosis X. This case report illustrates the need for more prospective, well-designed studies to determine the natural history and outcome of intestinal lymphangiectasia in the duodenum. Hopefully, these studies will also help clinicians identify which group of patients with intestinal lymphangiectasia in the duodenum is more likely to have a secondary cause.

Job Satisfaction of People With Intellectual Disability: Associations With Job Characteristics and Personality.

PubMed

Akkerman, Alma; Kef, Sabina; Meininger, Herman P

2018-01-01

To obtain an understanding of factors associated with job satisfaction of people with intellectual disability (ID), this study investigates the associations of job satisfaction with job characteristics (i.e., job demands, job resources) and personality, using the job demands-resources model. Data were gathered from 117 people and their employment support workers, using structured questionnaires adapted from well-established instruments. Job resources and age were positively associated with job satisfaction. Job demands and personality showed no significant direct associations with job satisfaction. Moderation analyses showed that for people with ID with high conscientiousness, enhanced job demands were associated with reduced job satisfaction, which was not the case for those with low conscientiousness. This study emphasizes the importance of job design.

Overweight and obesity are progressively associated with lower work ability in the general working population: cross-sectional study among 10,000 adults.

PubMed

Andersen, Lars L; Izquierdo, Mikel; Sundstrup, Emil

2017-11-01

Obesity is associated with many diseases and functional limitations. Workplaces are not always designed to accommodate this challenge. This study investigated the association between body mass index (BMI) and work ability in the general working population. Currently employed wage earners (N = 10,427) from the 2010 round of the Danish Work Environment Cohort Study (DWECS) replied to questions about work and health. Cumulative logistic regression analyses controlling for age, gender, physical and psychosocial work factors, lifestyle, and chronic diseases modeled the associations between BMI and work ability. BMIs above the normal range were progressively associated with lower work ability in relation to the physical demands of the job. Odds ratios for having lower work ability were 1.11 (95% CI 1.01-1.22), 1.17 (95% CI 1.01-1.34), 1.43 (95% CI 1.09-1.88), 1.69 (95% CI 1.10-2.62) for overweight and obesity classes I, II, and III, respectively. In subgroup analyses, the associations between BMI and work ability were more pronounced among individuals with mainly sedentary work than among those with physically active work. BMI was not associated with work ability in relation to the mental demands of the work. BMIs above the normal range are progressively associated with lower work ability in relation to the physical demands of the job, especially among individuals with mainly sedentary work. Ergonomic research on how to optimally design workstations for workers with obesity are needed.

Prediction of contact mechanics in metal-on-metal Total Hip Replacement for parametrically comprehensive designs and loads.

PubMed

Donaldson, Finn E; Nyman, Edward; Coburn, James C

2015-07-16

Manufacturers and investigators of Total Hip Replacement (THR) bearings require tools to predict the contact mechanics resulting from diverse design and loading parameters. This study provides contact mechanics solutions for metal-on-metal (MoM) bearings that encompass the current design space and could aid pre-clinical design optimization and evaluation. Stochastic finite element (FE) simulation was used to calculate the head-on-cup contact mechanics for five thousand combinations of design and loading parameters. FE results were used to train a Random Forest (RF) surrogate model to rapidly predict the contact patch dimensions, contact area, pressures and plastic deformations for arbitrary designs and loading. In addition to widely observed polar and edge contact, FE results included ring-polar, asymmetric-polar, and transitional categories which have previously received limited attention. Combinations of design and load parameters associated with each contact category were identified. Polar contact pressures were predicted in the range of 0-200 MPa with no permanent deformation. Edge loading (with subluxation) was associated with pressures greater than 500 MPa and induced permanent deformation in 83% of cases. Transitional-edge contact (with little subluxation) was associated with intermediate pressures and permanent deformation in most cases, indicating that, even with ideal anatomical alignment, bearings may face extreme wear challenges. Surrogate models were able to accurately predict contact mechanics 18,000 times faster than FE analyses. The developed surrogate models enable rapid prediction of MoM bearing contact mechanics across the most comprehensive range of loading and designs to date, and may be useful to those performing bearing design optimization or evaluation. Published by Elsevier Ltd.

Study designs for identification of rare disease variants in complex diseases: the utility of family-based designs.

PubMed

Ionita-Laza, Iuliana; Ottman, Ruth

2011-11-01

The recent progress in sequencing technologies makes possible large-scale medical sequencing efforts to assess the importance of rare variants in complex diseases. The results of such efforts depend heavily on the use of efficient study designs and analytical methods. We introduce here a unified framework for association testing of rare variants in family-based designs or designs based on unselected affected individuals. This framework allows us to quantify the enrichment in rare disease variants in families containing multiple affected individuals and to investigate the optimal design of studies aiming to identify rare disease variants in complex traits. We show that for many complex diseases with small values for the overall sibling recurrence risk ratio, such as Alzheimer's disease and most cancers, sequencing affected individuals with a positive family history of the disease can be extremely advantageous for identifying rare disease variants. In contrast, for complex diseases with large values of the sibling recurrence risk ratio, sequencing unselected affected individuals may be preferable.

Factors Associated with Interest in Science of West African Students in Washington, D.C.

ERIC Educational Resources Information Center

Onwere, Godfrey O.

1980-01-01

Describes a study designed to identify factors which students from Gambia, Ghana, Liberia, Nigeria, and Sierra Leone associated with precollege interest in science and factors which influenced or contributed to the choice of a science major or dissuaded students from entering a scientific field. (Author/GC)

The Association between Science Summer Camps and Career Interest in Science and Engineering

ERIC Educational Resources Information Center

Kong, Xiaoqing; Dabney, Katherine P.; Tai, Robert H.

2014-01-01

This study addresses the association between middle-school students' reported participation in science summer programmes and their reported expectation of a career in science and engineering. Data were collected on 1,580 students from eight middle schools in five states, applying an accelerated longitudinal design. Two consecutive cohorts were…

Barriers Associated with Implementing a Campus-Wide Smoke-Free Policy

ERIC Educational Resources Information Center

Harbison, Philip Adam; Whitman, Marilyn V.

2008-01-01

Purpose: The purpose of this study is to review the barriers associated with implementing a campus-wide smoke-free policy as perceived by the American Cancer Society's Colleges against Cancer (CAC) Program chapter representatives. Design/methodology/approach: Four focus group sessions were conducted at the annual CAC National Leadership Summit in…

Evaluating Quality in Associate Degree Culinary Arts Programs

ERIC Educational Resources Information Center

Hertzman, Jean; Ackerman, Robert

2010-01-01

Purpose: The purpose of this study is to determine which categories and indicators of quality are best suited to evaluating associate degree culinary arts programs (ADCAP). Design/methodology/approach: The researchers surveyed a national sample of culinary educators and industry chefs in the USA. The instrument asked the participants to rate the…

Predictors for Associate Degree Nursing Students' First Attempt on NCLEX-RN

ERIC Educational Resources Information Center

Smith, Barbara A.

2011-01-01

Nursing program administrators need to identify significant predictors for associate degree nursing (ADN) students to determine characteristics of those who will most likely pass the NCLEX-RN® on the first attempt. The purpose of the quantitative study with a correlation prediction design was to determine if a relationship existed between the…

Associations between Parental Concern for Adolescent Weight and the Home Food Environment and Dietary Intake

ERIC Educational Resources Information Center

MacFarlane, Abbie; Crawford, David; Worsley, Anthony

2010-01-01

Objective: Examine associations between parental concern about adolescent weight and adolescent perceptions of their dietary intake, home food availability, family mealtime environment, and parents' feeding practices. Design: Cross-sectional study. Setting: Adolescents, aged 12-15 years from 37 secondary schools in Victoria, Australia, and their…

Lexical Selection Is Competitive: Evidence from Indirectly Activated Semantic Associates during Picture Naming

ERIC Educational Resources Information Center

Melinger, Alissa; Rahman, Rasha Abdel

2013-01-01

In this study, we present 3 picture-word interference (PWI) experiments designed to investigate whether lexical selection processes are competitive. We focus on semantic associative relations, which should interfere according to competitive models but not according to certain noncompetitive models. In a modified version of the PWI paradigm,…

Automatic Associations and Panic Disorder: Trajectories of Change over the Course of Treatment

ERIC Educational Resources Information Center

Teachman, Bethany A.; Marker, Craig D.; Smith-Janik, Shannan B.

2008-01-01

Cognitive models of anxiety and panic suggest that symptom reduction during treatment should be preceded by changes in cognitive processing, including modifying the anxious schema. The current study tested these hypotheses by using a repeated measures design to evaluate whether the trajectory of change in automatic panic associations over a…

Exploration of Social Cognitive Factors Associated with Physical Activity among Chinese-American Children

ERIC Educational Resources Information Center

Zhang, Yan; DeBate, Rita DiGioacchino

2006-01-01

This study examined the social cognitive factors associated with participation in physical activity among Chinese-American youth. Utilizing an observational cross-sectional design, data were collected via a self-administered survey from 84 Chinese-American children ages 6-18. The survey employed items from the Health Behavior Questionnaire and the…

Associations of Built Food Environment with Dietary Intake among Youth with Diabetes

ERIC Educational Resources Information Center

Lamichhane, Archana P.; Mayer-Davis, Elizabeth J.; Puett, Robin; Bottai, Matteo; Porter, Dwayne E.; Liese, Angela D.

2012-01-01

Objective: To evaluate the associations of supermarket and fast-food outlet accessibility and availability with dietary intake among youth with diabetes. Design: Subjects' residential location and dietary intake was obtained from the SEARCH for Diabetes in Youth study. Food outlet data obtained from the South Carolina Department of Health and…

Relationship between interpersonal trauma exposure and addictive behaviors: a systematic review.

PubMed

Konkolÿ Thege, Barna; Horwood, Lewis; Slater, Linda; Tan, Maria C; Hodgins, David C; Wild, T Cameron

2017-05-04

The aim of this study was to systematically summarize knowledge on the association between exposure to interpersonal trauma and addictive behaviors. Extant reviews on this association focused on a restricted range of substance-related addictions, and/or used a narrative instead of a systematic approach. Systematic searches of 8 databases yielded 29,841 studies, of which 3054 studies were included and subsequently classified in relation to study design (scoping review). A subset of observational studies (N = 181) prospectively investigating the relationship between exposure to interpersonal traumata and subsequent behavioral or substance-related addiction problems were characterized. Heterogeneity in study methodologies and types of addictive behaviors and traumatic experiences assessed precluded meta-analysis. Instead, the proportions of associations tested in this literature that revealed positive, negative, or null relationships between trauma exposure and subsequent addictive behaviors were recorded, along with other methodological features. Of 3054 included studies, 70.7% (n = 2160) used a cross-sectional design. In the 181 prospective observational studies (407,041 participants, 98.8% recruited from developed countries), 35.1% of the tested associations between trauma exposure and later addictive behaviors was positive, 1.3% was negative, and 63.6% was non-significant. These results were primarily obtained among non-treatment seeking samples (80.7% of studies; n = 146), using single and multi-item measures of addictive behaviors of unknown psychometric quality (46.4% of studies). Positive associations were more frequently observed in studies examining childhood versus adult traumatization (39.7% vs. 29.7%). Longitudinal research in this area emphasizes alcohol abuse, and almost no research has examined behavioral addictions. Results provide some support for a positive association between exposure to interpersonal trauma and subsequent addictive behaviors but this relationship was not consistently reported. Longitudinal studies typically assessed trauma exposure retrospectively, often after addictive behavior onset, thus precluding robust inferences about whether traumatization affects initial onset of addictive behaviors.

Definition study for variable cycle engine testbed engine and associated test program

NASA Technical Reports Server (NTRS)

Vdoviak, J. W.

1978-01-01

The product/study double bypass variable cycle engine (VCE) was updated to incorporate recent improvements. The effect of these improvements on mission range and noise levels was determined. This engine design was then compared with current existing high-technology core engines in order to define a subscale testbed configuration that simulated many of the critical technology features of the product/study VCE. Detailed preliminary program plans were then developed for the design, fabrication, and static test of the selected testbed engine configuration. These plans included estimated costs and schedules for the detail design, fabrication and test of the testbed engine and the definition of a test program, test plan, schedule, instrumentation, and test stand requirements.

An overview of the genetic dissection of complex traits.

PubMed

Rao, D C

2008-01-01

Thanks to the recent revolutionary genomic advances such as the International HapMap consortium, resolution of the genetic architecture of common complex traits is beginning to look hopeful. While demonstrating the feasibility of genome-wide association (GWA) studies, the pathbreaking Wellcome Trust Case Control Consortium (WTCCC) study also serves to underscore the critical importance of very large sample sizes and draws attention to potential problems, which need to be addressed as part of the study design. Even the large WTCCC study had vastly inadequate power for several of the associations reported (and confirmed) and, therefore, most of the regions harboring relevant associations may not be identified anytime soon. This chapter provides an overview of some of the key developments in the methodological approaches to genetic dissection of common complex traits. Constrained Bayesian networks are suggested as especially useful for analysis of pathway-based SNPs. Likewise, composite likelihood is suggested as a promising method for modeling complex systems. It discusses the key steps in a study design, with an emphasis on GWA studies. Potential limitations highlighted by the WTCCC GWA study are discussed, including problems associated with massive genotype imputation, analysis of pooled national samples, shared controls, and the critical role of interactions. GWA studies clearly need massive sample sizes that are only possible through genuine collaborations. After all, for common complex traits, the question is not whether we can find some pieces of the puzzle, but how large and what kind of a sample we need to (nearly) solve the genetic puzzle.

Correlates of Trail Use for Recreation and Transportation on 5 Massachusetts Trails.

PubMed

Orstad, Stephanie L; McDonough, Meghan H; Klenosky, David B; Mattson, Marifran; Troped, Philip J

2016-08-01

Promoting use of community trails is a recommended strategy for increasing population levels of physical activity. Correlates of walking and cycling for recreation or transportation differ, though few studies have compared correlates of trail-based physical activity for recreation and transportation purposes. This study examined associations of demographic, social, and perceived built environmental factors with trail use for recreation and transportation and whether associations were moderated by age, gender, and prior trail use. Adults (N = 1195) using 1 of 5 trails in Massachusetts responded to an intercept survey. We used multiple linear and logistic regression models to examine associations with trail use. Respondents' mean age was 44.9 years (standard deviation = 12.5), 55.3% were female, and 82.0% were white. Age (longer-term users only), trail use with others, travel time to the trail, and trail design were significantly associated with use for recreation (P < .05). Age, gender, trail safety (longer-term users only), travel time to the trail, trail design (younger users only), and trail beauty were associated with use for transportation (P < .05). Some common correlates were found for recreational and transportation trail use, whereas some variables were uniquely associated with use for 1 purpose. Tailored strategies are suggested to promote trail use for recreation and transportation.

Multimorbidity and its relation to subjective memory complaints in a large general population of older adults.

PubMed

Aarts, S; van den Akker, M; Hajema, K J; van Ingen, A M; Metsemakers, J F M; Verhey, F R J; van Boxtel, M P J

2011-05-01

Multimorbidity has been suggested to be associated with a variety of negative health-related outcomes. The present study was designed to evaluate the association between multimorbidity and subjective memory complaints. This cross-sectional study was based on data obtained from a postal survey designed by the Public Health Service (Gemeentelijke Gezondheids Dienst, GGD) involving 15,188 persons aged 55 years and over living independently in Limburg, the Netherlands. Multivariate logistic regression analyses, adjusted for potentially important covariates, were performed to evaluate the association between self-reported multimorbidity and three outcomes related to subjective memory complaints. Multimorbidity was indeed related to subjective memory complaints. The association between multimorbidity and subjective memory complaints was positively influenced by age. Moreover, multimorbidity was related to the degree of worrying about memory complaints in people who perceived themselves as forgetful. Multimorbidity was also associated with reporting a larger increase in these subjective memory complaints during the past year. In this latter case, multimorbidity had more prognostic capability in men than in women. Psychological distress was related to all three subjective memory-related outcome measures. In our sample, which was representative of the Dutch population, multimorbidity was associated with subjective memory complaints. The relationship between multimorbidity and subjective memory complaints differed between men and women and between age groups.

The effects of particulate air pollution on daily deaths: a multi-city case crossover analysis

PubMed Central

Schwartz, J

2004-01-01

Background: Numerous studies have reported that day-to-day changes in particulate air pollution are associated with day-to-day changes in deaths. Recently, several reports have indicated that the software used to control for season and weather in some of these studies had deficiencies. Aims: To investigate the use of the case-crossover design as an alternative. Methods: This approach compares the exposure of each case to their exposure on a nearby day, when they did not die. Hence it controls for seasonal patterns and for all slowly varying covariates (age, smoking, etc) by matching rather than complex modelling. A key feature is that temperature can also be controlled by matching. This approach was applied to a study of 14 US cities. Weather and day of the week were controlled for in the regression. Results: A 10 µg/m3 increase in PM10 was associated with a 0.36% increase in daily deaths from internal causes (95% CI 0.22% to 0.50%). Results were little changed if, instead of symmetrical sampling of control days the time stratified method was applied, when control days were matched on temperature, or when more lags of winter time temperatures were used. Similar results were found using a Poisson regression, but the case-crossover method has the advantage of simplicity in modelling, and of combining matched strata across multiple locations in a single stage analysis. Conclusions: Despite the considerable differences in analytical design, the previously reported associations of particles with mortality persisted in this study. The association appeared quite linear. Case-crossover designs represent an attractive method to control for season and weather by matching. PMID:15550600

A SAS-based solution to evaluate study design efficiency of phase I pediatric oncology trials via discrete event simulation.

PubMed

Barrett, Jeffrey S; Jayaraman, Bhuvana; Patel, Dimple; Skolnik, Jeffrey M

2008-06-01

Previous exploration of oncology study design efficiency has focused on Markov processes alone (probability-based events) without consideration for time dependencies. Barriers to study completion include time delays associated with patient accrual, inevaluability (IE), time to dose limiting toxicities (DLT) and administrative and review time. Discrete event simulation (DES) can incorporate probability-based assignment of DLT and IE frequency, correlated with cohort in the case of DLT, with time-based events defined by stochastic relationships. A SAS-based solution to examine study efficiency metrics and evaluate design modifications that would improve study efficiency is presented. Virtual patients are simulated with attributes defined from prior distributions of relevant patient characteristics. Study population datasets are read into SAS macros which select patients and enroll them into a study based on the specific design criteria if the study is open to enrollment. Waiting times, arrival times and time to study events are also sampled from prior distributions; post-processing of study simulations is provided within the decision macros and compared across designs in a separate post-processing algorithm. This solution is examined via comparison of the standard 3+3 decision rule relative to the "rolling 6" design, a newly proposed enrollment strategy for the phase I pediatric oncology setting.

76 FR 2674 - Proposed Waiver and Extension of Project Period

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-14

... the project. Additionally, PIRCs conducting experimental design studies experienced logistical challenges associated with establishing treatment and control groups. An additional year of funding would...

Musculoskeletal symptoms as related to ergonomic factors in Iranian hand-woven carpet industry and general guidelines for workstation design.

PubMed

Choobineh, Alireza; Lahmi, Mohammadali; Shahnavaz, Houshang; Jazani, Reza Khani; Hosseini, Mostafa

2004-01-01

Carpet weaving is a high risk occupation for developing musculoskeletal disorders (MSDs). The objectives of the present study, which was carried out in the Iranian hand-woven carpet industry, were determination of the prevalence of MSD symptoms, identification of major factors associated with MSD symptoms and development of guidelines for workstation design. 1,439 randomly selected weavers participated in this study. A questionnaire was used to collect data on MSD symptoms. The results revealed that the prevalence rates for symptoms in different body regions were high as compared to the general Iranian population (for neck, back and large joints, p <.0001). The results of multivariate analyses showed that major ergonomic factors associated with musculoskeletal symptoms were loom type, working posture, daily working time and seat type. Based on the results, some general guidelines for designing weaving workstations were developed. A prototype test showed that the new workstation was acceptable for subject tests and that it improved working posture.

Photochemical Reaction Altered Cardiac Toxicity of Diesel Exhaust Inhalation

EPA Science Inventory

Rationale: Epidemiological studies have indicated an association between urban air pollution exposure and cardiovascular morbidity and mortality. The present study was designed to evaluate the cardiac effects of inhaled diesel exhaust and compared with photochemically altered d...

"EPA'S NATIONAL BEACHES STUDY: HUNTINGTON BEACH, 2003"

EPA Science Inventory

The original U. S. Environmental Protection Agency (EPA) recreational water health studies, initiated in 1972 and completed in 1982, were designed to determine the relationship between swimming-associated gastroenteritis and the quality of the bathing water. However, these healt...

Design and Implementation of the International Genetics and Translational Research in Transplantation Network.

PubMed

2015-11-01

Genetic association studies of transplantation outcomes have been hampered by small samples and highly complex multifactorial phenotypes, hindering investigations of the genetic architecture of a range of comorbidities which significantly impact graft and recipient life expectancy. We describe here the rationale and design of the International Genetics & Translational Research in Transplantation Network. The network comprises 22 studies to date, including 16494 transplant recipients and 11669 donors, of whom more than 5000 are of non-European ancestry, all of whom have existing genomewide genotype data sets. We describe the rich genetic and phenotypic information available in this consortium comprising heart, kidney, liver, and lung transplant cohorts. We demonstrate significant power in International Genetics & Translational Research in Transplantation Network to detect main effect association signals across regions such as the MHC region as well as genomewide for transplant outcomes that span all solid organs, such as graft survival, acute rejection, new onset of diabetes after transplantation, and for delayed graft function in kidney only. This consortium is designed and statistically powered to deliver pioneering insights into the genetic architecture of transplant-related outcomes across a range of different solid-organ transplant studies. The study design allows a spectrum of analyses to be performed including recipient-only analyses, donor-recipient HLA mismatches with focus on loss-of-function variants and nonsynonymous single nucleotide polymorphisms.

Statins use and risk of depression: a systematic review and meta-analysis.

PubMed

Parsaik, Ajay K; Singh, Balwinder; Murad, M Hassan; Singh, Kuljit; Mascarenhas, Soniya S; Williams, Mark D; Lapid, Maria I; Richardson, Jarrett W; West, Colin P; Rummans, Teresa A

2014-05-01

Statin use has been associated with depression; however studies of the association between statin use and depression have yielded mixed results. To determine whether statin use is associated with depression and to evaluate the evidence supporting this association. Ovid MEDLINE In-Process & Other Non-Indexed Citations, Ovid MEDLINE, EMBASE, PsycInfo, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Scopus were searched through December 28, 2012. We included studies that evaluated exposure to statins, reported the development of depression, and relative risks or odds ratios (ORs) or provided data for their estimation. Two reviewers screened 981 abstracts independently using a standardized form, reviewed full text of 59 selected articles, and included 7 studies in this metaanalysis. Study design, statin exposure, development of depression, and study quality were extracted by 2 independent reviewers. A pooled OR with 95% confidence interval (CI) was estimated using the random-effects model and heterogeneity was assessed using Cochran's Q test and the I(2) statistic. Seven observational studies (4 cohort, 2 nested case-control, and 1 cross-sectional) from 5 countries enrolling 9187 patients were included. Statin users were 32% less likely to develop depression than nonusers (adjusted OR, 0.68; 95% CI, 0.52-0.89). Modest heterogeneity was observed between the studies (I(2)=55%, P=0.01), which could be accounted for by one study, exclusion of which removed the heterogeneity (P=0.40, I(2)=2%) and further strengthened the antidepressant effect of statin (adjusted OR, 0.63; 95% CI, 0.43-0.93). Heterogeneity could not be explained by study design or study population. The quality of supporting evidence was fair. This systematic review and meta-analysis suggests that statin use is associated with lower risk for depression. However, higher-quality studies are needed to confirm the magnitude of this association. Copyright © 2013 Elsevier B.V. All rights reserved.

Methodology Series Module 3: Cross-sectional Studies.

PubMed

Setia, Maninder Singh

2016-01-01

Cross-sectional study design is a type of observational study design. In a cross-sectional study, the investigator measures the outcome and the exposures in the study participants at the same time. Unlike in case-control studies (participants selected based on the outcome status) or cohort studies (participants selected based on the exposure status), the participants in a cross-sectional study are just selected based on the inclusion and exclusion criteria set for the study. Once the participants have been selected for the study, the investigator follows the study to assess the exposure and the outcomes. Cross-sectional designs are used for population-based surveys and to assess the prevalence of diseases in clinic-based samples. These studies can usually be conducted relatively faster and are inexpensive. They may be conducted either before planning a cohort study or a baseline in a cohort study. These types of designs will give us information about the prevalence of outcomes or exposures; this information will be useful for designing the cohort study. However, since this is a 1-time measurement of exposure and outcome, it is difficult to derive causal relationships from cross-sectional analysis. We can estimate the prevalence of disease in cross-sectional studies. Furthermore, we will also be able to estimate the odds ratios to study the association between exposure and the outcomes in this design.

Methodology Series Module 3: Cross-sectional Studies

PubMed Central

Setia, Maninder Singh

2016-01-01

Cross-sectional study design is a type of observational study design. In a cross-sectional study, the investigator measures the outcome and the exposures in the study participants at the same time. Unlike in case–control studies (participants selected based on the outcome status) or cohort studies (participants selected based on the exposure status), the participants in a cross-sectional study are just selected based on the inclusion and exclusion criteria set for the study. Once the participants have been selected for the study, the investigator follows the study to assess the exposure and the outcomes. Cross-sectional designs are used for population-based surveys and to assess the prevalence of diseases in clinic-based samples. These studies can usually be conducted relatively faster and are inexpensive. They may be conducted either before planning a cohort study or a baseline in a cohort study. These types of designs will give us information about the prevalence of outcomes or exposures; this information will be useful for designing the cohort study. However, since this is a 1-time measurement of exposure and outcome, it is difficult to derive causal relationships from cross-sectional analysis. We can estimate the prevalence of disease in cross-sectional studies. Furthermore, we will also be able to estimate the odds ratios to study the association between exposure and the outcomes in this design. PMID:27293245

A matched case-control study of convenience store robbery risk factors.

PubMed

Hendricks, S A; Landsittel, D P; Amandus, H E; Malcan, J; Bell, J

1999-11-01

Convenience store clerks have been shown to be at high risk for assault and homicide, mostly owing to robbery or robbery attempts. Although the literature consistently indicates that at least some environmental designs are effective deterrents of robbery, the significance of individual interventions and policies has differed across past studies. To address these issues, a matched case-control study of 400 convenience store robberies in three metropolitan areas of Virginia was conducted. Conditional logistic regression was implemented to evaluate the significance of various environmental designs and other factors possibly related to convenience store robbery. Findings indicate that numerous characteristics of the surrounding environment and population were significantly associated with convenience store robbery. Results also showed that, on a univariate level, most crime prevention factors were significantly associated with a lower risk for robbery. Using a forward selection process, a multivariate model, which included cash handling policy, bullet-resistant shielding, and numerous characteristics of the surrounding area and population, was identified. This study addressed numerous limitations of the previous literature by prospectively collecting extensive data on a large sample of diverse convenience stores and directly addressing the current theory on the robbers' selection of a target store through a matched case-control design.

The reduction of health care costs associated with alcoholism treatment: a 14-year longitudinal study.

PubMed

Holder, H D; Blose, J O

1992-07-01

This study utilized two separate research designs to examine whether the initiation of alcoholism treatment is associated with a change in overall medical care cost in a population of alcoholics enrolled under a health plan sponsored by a large midwestern manufacturing corporation. In the longest longitudinal study of alcoholism treatment costs to date, a review of claims filed from 1974 to 1987 identified 3,729 alcoholics (3,068 of whom received treatment and 661 of whom did not). In one design, a time-series analysis found that following treatment initiation the total health care costs of treated alcoholics--including the cost of alcoholism treatment--declined by 23% to 55% from their highest pretreatment levels. Costs for identified but untreated alcoholics rose following identification. In a second design, analysis of variance was used to control for group differences including pretreatment health status and age. This analysis indicated that the posttreatment costs of treated alcoholics were 24% lower than comparable costs for untreated alcoholics. The study provides considerable evidence that alcoholism treatment can reduce overall medical costs in a heterogeneous alcoholic population (white collar/blue collar; fee-for-service/HMO).

Evidence mapping of whole grain intervention studies, health outcomes, and reporting practices

USDA-ARS?s Scientific Manuscript database

Higher consumption of whole grain foods is associated with reduced risk of cardiovascular disease, diabetes, and obesity in observational studies; yet, in intervention studies, the effect of whole grains on intermediate markers of risk are mixed. This may be due to the variability in study design, d...

THE 1998 BALTIMORE PARTICULATE MATTER EPIDEMIOLOGY-EXPOSURE STUDY: PART 2-PERSONAL EXPOSURE ASSESSMENT ASSOCIATED WITH AN ELDERLY STUDY POPULATION

EPA Science Inventory

An integrated epidemiological-exposure panel study was conducted during the summer of 1998 which focused upon establishing relationships between potential human exposures to particulate matter (PM) and related co-pollutants with detectable health effects. The study design incor...

Methodological quality of behavioural weight loss studies: a systematic review

PubMed Central

Lemon, S. C.; Wang, M. L.; Haughton, C. F.; Estabrook, D. P.; Frisard, C. F.; Pagoto, S. L.

2018-01-01

Summary This systematic review assessed the methodological quality of behavioural weight loss intervention studies conducted among adults and associations between quality and statistically significant weight loss outcome, strength of intervention effectiveness and sample size. Searches for trials published between January, 2009 and December, 2014 were conducted using PUBMED, MEDLINE and PSYCINFO and identified ninety studies. Methodological quality indicators included study design, anthropometric measurement approach, sample size calculations, intent-to-treat (ITT) analysis, loss to follow-up rate, missing data strategy, sampling strategy, report of treatment receipt and report of intervention fidelity (mean = 6.3). Indicators most commonly utilized included randomized design (100%), objectively measured anthropometrics (96.7%), ITT analysis (86.7%) and reporting treatment adherence (76.7%). Most studies (62.2%) had a follow-up rate >75% and reported a loss to follow-up analytic strategy or minimal missing data (69.9%). Describing intervention fidelity (34.4%) and sampling from a known population (41.1%) were least common. Methodological quality was not associated with reporting a statistically significant result, effect size or sample size. This review found the published literature of behavioural weight loss trials to be of high quality for specific indicators, including study design and measurement. Identified for improvement include utilization of more rigorous statistical approaches to loss to follow up and better fidelity reporting. PMID:27071775

Development of Crystallizer for Advanced Aqueous Reprocessing Process

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

Tadahiro Washiya; Atsuhiro Shibata; Toshiaki Kikuchi

2006-07-01

Crystallization is one of the remarkable technologies for future fuel reprocessing process that has safety and economical advantages. Japan Atomic Energy Agency (JAEA) (former Japan Nuclear Cycle Development Institute), Mitsubishi Material Corporation and Saitama University have been developing the crystallization process. In previous study, we carried out experimental studies with uranium, MOX and spent fuel conditions, and flowsheet analysis was considered. In association with these studies, an innovative continuous crystallizer and its system was developed to ensure high process performance. From the design study, an annular type continuous crystallizer was selected as the most promising design, and performance was confirmedmore » by small-scale test and engineering scale demonstration at uranium crystallization conditions. In this paper, the design study and the demonstration test results are described. (authors)« less

WISARD: workbench for integrated superfast association studies for related datasets.

PubMed

Lee, Sungyoung; Choi, Sungkyoung; Qiao, Dandi; Cho, Michael; Silverman, Edwin K; Park, Taesung; Won, Sungho

2018-04-20

A Mendelian transmission produces phenotypic and genetic relatedness between family members, giving family-based analytical methods an important role in genetic epidemiological studies-from heritability estimations to genetic association analyses. With the advance in genotyping technologies, whole-genome sequence data can be utilized for genetic epidemiological studies, and family-based samples may become more useful for detecting de novo mutations. However, genetic analyses employing family-based samples usually suffer from the complexity of the computational/statistical algorithms, and certain types of family designs, such as incorporating data from extended families, have rarely been used. We present a Workbench for Integrated Superfast Association studies for Related Data (WISARD) programmed in C/C++. WISARD enables the fast and a comprehensive analysis of SNP-chip and next-generation sequencing data on extended families, with applications from designing genetic studies to summarizing analysis results. In addition, WISARD can automatically be run in a fully multithreaded manner, and the integration of R software for visualization makes it more accessible to non-experts. Comparison with existing toolsets showed that WISARD is computationally suitable for integrated analysis of related subjects, and demonstrated that WISARD outperforms existing toolsets. WISARD has also been successfully utilized to analyze the large-scale massive sequencing dataset of chronic obstructive pulmonary disease data (COPD), and we identified multiple genes associated with COPD, which demonstrates its practical value.

Rationally designed small molecules targeting the RNA that causes myotonic dystrophy type 1 are potently bioactive.

PubMed

Childs-Disney, Jessica L; Hoskins, Jason; Rzuczek, Suzanne G; Thornton, Charles A; Disney, Matthew D

2012-05-18

RNA is an important drug target, but it is difficult to design or discover small molecules that modulate RNA function. In the present study, we report that rationally designed, modularly assembled small molecules that bind the RNA that causes myotonic dystrophy type 1 (DM1) are potently bioactive in cell culture models. DM1 is caused when an expansion of r(CUG) repeats, or r(CUG)(exp), is present in the 3' untranslated region (UTR) of the dystrophia myotonica protein kinase (DMPK) mRNA. r(CUG)(exp) folds into a hairpin with regularly repeating 5'CUG/3'GUC motifs and sequesters muscleblind-like 1 protein (MBNL1). A variety of defects are associated with DM1, including (i) formation of nuclear foci, (ii) decreased translation of DMPK mRNA due to its nuclear retention, and (iii) pre-mRNA splicing defects due to inactivation of MBNL1, which controls the alternative splicing of various pre-mRNAs. Previously, modularly assembled ligands targeting r(CUG)(exp) were designed using information in an RNA motif-ligand database. These studies showed that a bis-benzimidazole (H) binds the 5'CUG/3'GUC motif in r(CUG)(exp.) Therefore, we designed multivalent ligands to bind simultaneously multiple copies of this motif in r(CUG)(exp). Herein, we report that the designed compounds improve DM1-associated defects including improvement of translational and pre-mRNA splicing defects and the disruption of nuclear foci. These studies may establish a foundation to exploit other RNA targets in genomic sequence.

Characterization of cationic liposome formulations designed to exhibit extended plasma residence times and tumor vasculature targeting properties.

PubMed

Ho, Emmanuel A; Ramsay, Euan; Ginj, Mihaela; Anantha, Malathi; Bregman, Isaiah; Sy, Jonathan; Woo, Janet; Osooly-Talesh, Maryam; Yapp, Donald T; Bally, Marcel B

2010-06-01

Cationic liposomes exhibit a propensity to selectively target tumor-associated blood vessels demonstrating potential value as anti-cancer drug delivery vehicles. Their utility however, is hampered by their biological instability and rapid elimination following i.v. administration. Efforts to circumvent rapid plasma elimination have, to date, focused on decreasing cationic lipid content and incorporating polyethylene glycol (PEG)-modified lipids. In this study we wanted to determine whether highly charged cationic liposomes with surface-associated PEG could be designed to exhibit extended circulation lifetimes, while retaining tumor vascular targeting properties in an HT29 colorectal cancer xenograft model. Cationic liposomes prepared of DSPC, cationic lipids (DODAC, DOTAP, or DC-CHOL), and DSPE-PEG(2000) were studied. Our results demonstrate that formulations prepared with 50 mol% DODAC or DC-CHOL, and 20 mol% DSPE-PEG(2000) exhibited circulation half-lives ranging from 6.5 to 12.5 h. Biodistribution studies demonstrated that DC-CHOL formulations prepared with DSPE-PEG(2000) accumulated threefold higher in s.c. HT29 tumors than its PEG-free counterpart. Fluorescence microscopy studies suggested that the presence of DSPE-PEG(2000) did not adversely affect liposomal tumor vasculature targeting. We show for the first time that it is achievable to design highly charged, highly pegylated (20 mol% DSPE-PEG(2000)) cationic liposomes which exhibit both extended circulation lifetimes and tumor vascular targeting properties. (c) 2010 Wiley-Liss, Inc. and the American Pharmacists Association

Are Health Plan Design and Prior Use of Long-Acting Reversible Contraception Associated with Pregnancy Intention?

PubMed

Armstrong, Mary Anne; Postlethwaite, Debbie A; Darbinian, Jeanne A; McCoy, Mark; Law, Amy

2017-05-01

In 2007, high-deductible plans were added to the primarily nondeductible Kaiser Permanente Northern California (KPNC) integrated health plan, which had covered 100% of device and procedure costs of long-acting reversible contraception (LARC) for members regardless of prescription/visit copay amount. We hypothesized that nondeductible plans and prior LARC use decreased unintended pregnancy. The purpose of this study was to determine if health plan design (nondeductible vs. deductible) and LARC use before pregnancy were associated with pregnancy intention. In this retrospective cohort study, women aged 15-44 as of the index date of June 30, 2010 were followed from January 1, 2010 to December 31, 2012 for evidence of pregnancy (n = 65,989). Health plan design, copays, contraceptive method used most recently before the pregnancy, and self-reported pregnancy intention status (intended, mistimed, unwanted) were obtained from electronic medical records. Logistic regression models were developed to determine if various health plan designs, copays, or prior LARC use were associated with pregnancy intention, controlling for potential confounders such as age, race/ethnicity, marital status, education/income, parity, and comorbidities. In all models, LARC use before pregnancy versus non-LARC use was significantly related to intended pregnancies (all models: odds ratio [OR] = 2.26, 95% confidence interval [CI] 2.06-2.48). Women with deductible plans with healthcare spending accounts (HSA) were more likely to report intended pregnancies versus women with nondeductible plans (all models: OR = 1.2, 95% CI 1.04-1.30). In stratified analyses, high income/high education was a significant predictor of intended pregnancy regardless of race/ethnicity. LARC use before pregnancy and having an HSA were associated with intended pregnancy.

Let it go: Relationship autonomy predicts pro-relationship responses to partner transgressions.

PubMed

Hadden, Benjamin W; Baker, Zachary G; Knee, C Raymond

2017-11-24

The purpose of the present research is to better understand how relationship autonomy-having more self-determined reasons for being committed to a relationship-contributes to pro-relationship responses to transgressions in romantic relationships (e.g., forgiveness and accommodation). Study 1 employed a cross-sectional design (N = 350) and Study 2 used a weekly diary (N = 121) to test associations between relationship autonomy and pro-relationship responses to transgressions. Studies 3 and 4 utilized dyadic designs (Study 3: N = 200 couples, 400 individuals; Study 4: N = 275 couples, 550 individuals) to determine how both partners' relationship autonomy is associated with pro-relationship responses. Results revealed that relationship autonomy is robustly associated with pro-relationship responses to transgressions, both as general tendencies and as responses to idiosyncratic transgressions. Results of actor-partner interdependence model (APIM) analyses in Studies 3 and 4 provide evidence that one's partner's relationship autonomy is important for promoting pro-relationship responses as well. Study 4 also found that people perceive that partners respond better to transgressions if their partner is high in relationship autonomy. This research provides consistent and compelling evidence that the degree of self-determination underlying commitment is important for understanding how people respond to transgressions in their relationships, beyond their current levels of commitment. © 2017 Wiley Periodicals, Inc.

The Use and Interpretation of Quasi-Experimental Studies in Medical Informatics

PubMed Central

Harris, Anthony D.; McGregor, Jessina C.; Perencevich, Eli N.; Furuno, Jon P.; Zhu, Jingkun; Peterson, Dan E.; Finkelstein, Joseph

2006-01-01

Quasi-experimental study designs, often described as nonrandomized, pre-post intervention studies, are common in the medical informatics literature. Yet little has been written about the benefits and limitations of the quasi-experimental approach as applied to informatics studies. This paper outlines a relative hierarchy and nomenclature of quasi-experimental study designs that is applicable to medical informatics intervention studies. In addition, the authors performed a systematic review of two medical informatics journals, the Journal of the American Medical Informatics Association (JAMIA) and the International Journal of Medical Informatics (IJMI), to determine the number of quasi-experimental studies published and how the studies are classified on the above-mentioned relative hierarchy. They hope that future medical informatics studies will implement higher level quasi-experimental study designs that yield more convincing evidence for causal links between medical informatics interventions and outcomes. PMID:16221933

Predicting Risk of Type 2 Diabetes Mellitus with Genetic Risk Models on the Basis of Established Genome-wide Association Markers: A Systematic Review

PubMed Central

Bao, Wei; Hu, Frank B.; Rong, Shuang; Rong, Ying; Bowers, Katherine; Schisterman, Enrique F.; Liu, Liegang; Zhang, Cuilin

2013-01-01

This study aimed to evaluate the predictive performance of genetic risk models based on risk loci identified and/or confirmed in genome-wide association studies for type 2 diabetes mellitus. A systematic literature search was conducted in the PubMed/MEDLINE and EMBASE databases through April 13, 2012, and published data relevant to the prediction of type 2 diabetes based on genome-wide association marker–based risk models (GRMs) were included. Of the 1,234 potentially relevant articles, 21 articles representing 23 studies were eligible for inclusion. The median area under the receiver operating characteristic curve (AUC) among eligible studies was 0.60 (range, 0.55–0.68), which did not differ appreciably by study design, sample size, participants’ race/ethnicity, or the number of genetic markers included in the GRMs. In addition, the AUCs for type 2 diabetes did not improve appreciably with the addition of genetic markers into conventional risk factor–based models (median AUC, 0.79 (range, 0.63–0.91) vs. median AUC, 0.78 (range, 0.63–0.90), respectively). A limited number of included studies used reclassification measures and yielded inconsistent results. In conclusion, GRMs showed a low predictive performance for risk of type 2 diabetes, irrespective of study design, participants’ race/ethnicity, and the number of genetic markers included. Moreover, the addition of genome-wide association markers into conventional risk models produced little improvement in predictive performance. PMID:24008910

Conflicting relationship between dietary intake and metabolic health in PTSD: A systematic review.

PubMed

Theal, Rebecca; Tay, Valerie Xin Pei; Hickman, Ingrid J

2018-06-01

Posttraumatic stress disorder (PTSD) is a disabling psychological condition associated with significant physical comorbidities. There has been growing evidence to support the relationship between PTSD and cardiometabolic disease. Disordered eating behaviors often seen in people with PTSD symptoms may explain increased cardiometabolic risk. This systematic review aimed to assess the quality of evidence surrounding dietary intake of individuals with symptoms or a diagnosis of PTSD and their associated risk with cardiometabolic health outcomes. Online databases Scopus, ProQuest (Health), Embase, Medline, PsycINFO, and CINAHL with Full Text were searched for peer-reviewed English articles prior to December 2017 that examined dietary intake and cardiometabolic health outcomes in adults with PTSD symptoms or diagnosis. The quality of each study was graded based on the design and methodology using adapted quality assessment tools. Seven studies with five unique participant samples were included in the review. Study methods, design, populations, and outcomes were inconsistent across studies. Dietary intake was considerably varied and limited associations were demonstrated between dietary intake and cardiometabolic risk factors in the PTSD cohorts. Due to the variability of measures and study outcomes, there was insufficient evidence to determine the relationship between dietary intake and PTSD-related cardiometabolic health outcomes. Future studies are needed to examine these associations in individuals with PTSD: specifically higher quality descriptive studies are necessary to confirm a link between diet and cardiometabolic disease in PTSD. Copyright © 2018 Elsevier Inc. All rights reserved.

Some (But Not Much) Progress Toward Understanding Teenage Childbearing: A Review of Research From the Past Decade

PubMed Central

Coyne, Claire A.; D’Onofrio, Brian M.

2013-01-01

In the decade and a half since Coley & Chase-Lansdale’s (1998) review of teenage childbearing there have been a number of studies investigating teenage childbearing from a developmental psychological perspective. Many of these studies have focused primarily on identifying individual, familial, and socioeconomic risk factors in childhood and adolescence that are highly correlated with teenage sexual behavior and teenage childbearing. We have an emerging understanding of teenage childbearing as the culmination of a complex cascade of experiences and decisions that overlap greatly with the risks for antisocial behavior. Much of this research, however, is limited by its reliance on correlational and cross-sectional research designs, which are not able to rigorously test causal inferences or to identify mechanisms associated with teenage childbearing. Innovative studies using large, nationally representative samples with quasi-experimental and longitudinal designs can expand on such descriptive studies. In particular, quasi-experimental studies can help answer questions about which risk factors are causally associated with teenage childbearing and suggest potential mechanisms that can explain how teenage childbearing is associated with poor outcomes. Future studies also will need to incorporate more precise measures of developmental processes and explore heterogeneity among adolescent mothers. Although advances have been made in the psychological study of teenage childbearing, more research is needed in order to answer important questions about which psychological processes are causally related to teenage childbearing and how teenage childbearing is associated with poor outcomes for young mothers and their offspring. PMID:22675905

Integrated design and manufacturing for the high speed civil transport

NASA Technical Reports Server (NTRS)

Lee, Jae Moon; Gupta, Anurag; Mueller, Craig; Morrisette, Monica; Dec, John; Brewer, Jason; Donofrio, Kevin; Sturisky, Hilton; Smick, Doug; An, Meng Lin

1994-01-01

In June 1992, the School of Aerospace Engineering at Georgia Tech was awarded a three year NASA University Space Research Association (USRA) Advanced Design Program (ADP) grant to address issues associated with the Integrated Design and Manufacturing of High Speed Civil Transport (HSCT) configurations in its graduate Aerospace Systems Design courses. This report provides an overview of the on-going Georgia Tech initiative to address these design/manufacturing issues during the preliminary design phases of an HSCT concept. The new design methodology presented here has been incorporated in the graduate aerospace design curriculum and is based on the concept of Integrated Product and Process Development (IPPD). The selection of the HSCT as a pilot project was motivated by its potential global transportation payoffs; its technological, environmental, and economic challenges; and its impact on U.S. global competitiveness. This pilot project was the focus of each of the five design courses that form the graduate level aerospace systems design curriculum. This year's main objective was the development of a systematic approach to preliminary design and optimization and its implementation to an HSCT wing/propulsion configuration. The new methodology, based on the Taguchi Parameter Design Optimization Method (PDOM), was established and was used to carry out a parametric study where various feasible alternative configurations were evaluated. The comparison criterion selected for this evaluation was the economic impact of this aircraft, measured in terms of average yield per revenue passenger mile ($/RPM).

Universalism under siege? Exploring the association between targeting, child benefits and child poverty across 26 countries.

PubMed

Van Lancker, Wim; Van Mechelen, Natascha

2015-03-01

The long-standing wisdom that universally designed benefits outperform targeted benefits in terms of poverty reduction has come under siege. Recent empirical studies tend to find that targeting is not necessarily associated anymore with lower levels of poverty reduction. In this study, we investigate for a broad set of European countries (1) the relationship between child benefits and child poverty reduction; (2) whether a universal or targeted approach is more effective in reducing child poverty; and (3) the causal mechanisms explaining the link between (1) and (2). In doing so, we take into account the general characteristics of the child benefit system, the size of the redistributive budget and the generosity of benefit levels. In contrast to previous studies, we construct an indicator of targeting that captures the design instead of the outcomes of child benefit systems. We find that targeting towards lower incomes is associated with higher levels of child poverty reduction, conditional on the direction of targeting and the characteristics of the benefit system. Copyright © 2014 Elsevier Inc. All rights reserved.

Five schools of thought about complexity: Implications for design and process science

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

Warfield, J.N.

1996-12-31

The prevalence of complexity is a fact of life in virtually all aspects of system design today. Five schools of thought concerning complexity seem to be present in areas where people strive to gain more facility with difficult issues: (1) Interdisciplinary or Cross-Disciplinary {open_quotes}approaches{close_quotes} or {open_quotes}methods{close_quotes} (fostered by the Association for Integrative Studies, a predominantly liberal-arts faculty activity), (2) Systems Dynamics (fostered by Jay Forrester, Dennis Meadows, Peter Senge, and others closely associated with MIT), (3) Chaos Theory (arising in small groups in many locations), (4) Adaptive Systems Theory (predominantly associated with the Santa Fe Institute), and (5) The Structure-Basedmore » school (developed by the author, his colleagues and associates). A comparison of these five schools of thought will be offered, in order to show the implications of them upon the development and application of design and process science. The following criteria of comparison will be used: (a) how complexity is defined, (b) analysis versus synthesis, (c) potential for acquiring practical competence in coping with complexity, and (d) relationship to underlying formalisms that facilitate computer assistance in applications. Through these comparisons, the advantages and disadvantages of each school of thought can be clarified, and the possibilities of changes in the educational system to provide for the management of complexity in system design can be articulated.« less

Design Characteristics Influence Performance of Clinical Prediction Rules in Validation: A Meta-Epidemiological Study

PubMed Central

Ban, Jong-Wook; Emparanza, José Ignacio; Urreta, Iratxe; Burls, Amanda

2016-01-01

Background Many new clinical prediction rules are derived and validated. But the design and reporting quality of clinical prediction research has been less than optimal. We aimed to assess whether design characteristics of validation studies were associated with the overestimation of clinical prediction rules’ performance. We also aimed to evaluate whether validation studies clearly reported important methodological characteristics. Methods Electronic databases were searched for systematic reviews of clinical prediction rule studies published between 2006 and 2010. Data were extracted from the eligible validation studies included in the systematic reviews. A meta-analytic meta-epidemiological approach was used to assess the influence of design characteristics on predictive performance. From each validation study, it was assessed whether 7 design and 7 reporting characteristics were properly described. Results A total of 287 validation studies of clinical prediction rule were collected from 15 systematic reviews (31 meta-analyses). Validation studies using case-control design produced a summary diagnostic odds ratio (DOR) 2.2 times (95% CI: 1.2–4.3) larger than validation studies using cohort design and unclear design. When differential verification was used, the summary DOR was overestimated by twofold (95% CI: 1.2 -3.1) compared to complete, partial and unclear verification. The summary RDOR of validation studies with inadequate sample size was 1.9 (95% CI: 1.2 -3.1) compared to studies with adequate sample size. Study site, reliability, and clinical prediction rule was adequately described in 10.1%, 9.4%, and 7.0% of validation studies respectively. Conclusion Validation studies with design shortcomings may overestimate the performance of clinical prediction rules. The quality of reporting among studies validating clinical prediction rules needs to be improved. PMID:26730980

Design Characteristics Influence Performance of Clinical Prediction Rules in Validation: A Meta-Epidemiological Study.

PubMed

Ban, Jong-Wook; Emparanza, José Ignacio; Urreta, Iratxe; Burls, Amanda

2016-01-01

Many new clinical prediction rules are derived and validated. But the design and reporting quality of clinical prediction research has been less than optimal. We aimed to assess whether design characteristics of validation studies were associated with the overestimation of clinical prediction rules' performance. We also aimed to evaluate whether validation studies clearly reported important methodological characteristics. Electronic databases were searched for systematic reviews of clinical prediction rule studies published between 2006 and 2010. Data were extracted from the eligible validation studies included in the systematic reviews. A meta-analytic meta-epidemiological approach was used to assess the influence of design characteristics on predictive performance. From each validation study, it was assessed whether 7 design and 7 reporting characteristics were properly described. A total of 287 validation studies of clinical prediction rule were collected from 15 systematic reviews (31 meta-analyses). Validation studies using case-control design produced a summary diagnostic odds ratio (DOR) 2.2 times (95% CI: 1.2-4.3) larger than validation studies using cohort design and unclear design. When differential verification was used, the summary DOR was overestimated by twofold (95% CI: 1.2 -3.1) compared to complete, partial and unclear verification. The summary RDOR of validation studies with inadequate sample size was 1.9 (95% CI: 1.2 -3.1) compared to studies with adequate sample size. Study site, reliability, and clinical prediction rule was adequately described in 10.1%, 9.4%, and 7.0% of validation studies respectively. Validation studies with design shortcomings may overestimate the performance of clinical prediction rules. The quality of reporting among studies validating clinical prediction rules needs to be improved.

Association Between Substance Use and Gun-Related Behaviors

PubMed Central

Chen, Danhong; Wu, Li-Tzy

2016-01-01

Gun-related violence is a public health concern. This study synthesizes findings on associations between substance use and gun-related behaviors. Searches through PubMed, Embase, and PsycINFO located 66 studies published in English between 1992 and 2014. Most studies found a significant bivariate association between substance use and increased odds of gun-related behaviors. However, their association after adjustment was mixed, which could be attributed to a number of factors such as variations in definitions of substance use and gun activity, study design, sample demographics, and the specific covariates considered. Fewer studies identified a significant association between substance use and gun access/possession than other gun activities. The significant association between nonsubstance covariates (e.g., demographic covariates and other behavioral risk factors) and gun-related behaviors might have moderated the association between substance use and gun activities. Particularly, the strength of association between substance use and gun activities tended to reduce appreciably or to become nonsignificant after adjustment for mental disorders. Some studies indicated a positive association between the frequency of substance use and the odds of engaging in gun-related behaviors. Overall, the results suggest a need to consider substance use in research and prevention programs for gun-related violence. PMID:26769722

Standard spacecraft economic analysis. Volume 2: Findings and conclusions

NASA Technical Reports Server (NTRS)

Harris, E. D.; Large, J. P.

1976-01-01

The comparative program costs associated with use of various standardized spacecraft for Air Force space test program missions to be flown on the space shuttle were studied in two phases. In the first phase, a variety of procurement mixes composed of existing or programmed NASA standard spacecraft designs and an Air Force standard spacecraft design were considered. The second phase dealt with additional procurement options using an upgraded version of an existing NASA design. The results of both phases are discussed.

MWASTools: an R/bioconductor package for metabolome-wide association studies.

PubMed

Rodriguez-Martinez, Andrea; Posma, Joram M; Ayala, Rafael; Neves, Ana L; Anwar, Maryam; Petretto, Enrico; Emanueli, Costanza; Gauguier, Dominique; Nicholson, Jeremy K; Dumas, Marc-Emmanuel

2018-03-01

MWASTools is an R package designed to provide an integrated pipeline to analyse metabonomic data in large-scale epidemiological studies. Key functionalities of our package include: quality control analysis; metabolome-wide association analysis using various models (partial correlations, generalized linear models); visualization of statistical outcomes; metabolite assignment using statistical total correlation spectroscopy (STOCSY); and biological interpretation of metabolome-wide association studies results. The MWASTools R package is implemented in R (version  > =3.4) and is available from Bioconductor: https://bioconductor.org/packages/MWASTools/. m.dumas@imperial.ac.uk. Supplementary data are available at Bioinformatics online. © The Author(s) 2017. Published by Oxford University Press.

An Evaluation of Different Target Enrichment Methods in Pooled Sequencing Designs for Complex Disease Association Studies

PubMed Central

Day-Williams, Aaron G.; McLay, Kirsten; Drury, Eleanor; Edkins, Sarah; Coffey, Alison J.; Palotie, Aarno; Zeggini, Eleftheria

2011-01-01

Pooled sequencing can be a cost-effective approach to disease variant discovery, but its applicability in association studies remains unclear. We compare sequence enrichment methods coupled to next-generation sequencing in non-indexed pools of 1, 2, 10, 20 and 50 individuals and assess their ability to discover variants and to estimate their allele frequencies. We find that pooled resequencing is most usefully applied as a variant discovery tool due to limitations in estimating allele frequency with high enough accuracy for association studies, and that in-solution hybrid-capture performs best among the enrichment methods examined regardless of pool size. PMID:22069447

Do Alzheimer's Disease Patients Want to Participate in a Treatment Decision, and Would Their Caregivers Let Them?

ERIC Educational Resources Information Center

Hirschman, Karen B.; Joyce, Colette M.; James, Bryan D.; Xie, Sharon X.; Karlawish, Jason H.T.

2005-01-01

Purpose: This study was designed to examine the factors associated with the preferences of Alzheimer's disease patients to participate in a decision to use an Alzheimer's disease-slowing medication and how involved their caregivers would let them be in this decision. Design and Methods: Interviews were conducted with 48 patients in the…

Designing Inter-Organizational Networks to Implement Education Reform: An Analysis of State Race to the Top Applications

ERIC Educational Resources Information Center

Russell, Jennifer Lin; Meredith, Julie; Childs, Joshua; Stein, Mary Kay; Prine, Deanna Weber

2015-01-01

This study sought to understand the opportunities and challenges associated with the implementation of state designed Race to the Top (RttT) funded reform networks. Drawing on a conceptual framework developed from the networked governance literature, we analyzed the 12 state RttT grantees' applications. Our analysis revealed that states designed…

A study of hydrocarbons associated with brines from DOE geopressured wells. Final report

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

Keeley, D.F.

1993-07-01

Accomplishments are summarized on the following tasks: distribution coefficients and solubilities, DOE design well sampling, analysis of well samples, review of theoretical models of geopressured reservoir hydrocarbons, monitor for aliphatic hydrocarbons, development of a ph meter probe, DOE design well scrubber analysis, removal and disposition of gas scrubber equipment at Pleasant Bayou Well, and disposition of archived brines.

Gender Differences in Predictors of Suicidal Thoughts and Attempts Among Homeless Veterans that Abuse Substances

ERIC Educational Resources Information Center

Benda, Brent B.

2005-01-01

This study of 315 male and 310 female homeless military veterans in a V.A. inpatient program designed to treat substance abusers, many of whom also suffer psychiatric disorders, was designed to examine gender differences in factors associated with the odds of having suicidal thoughts, and of attempting suicide, in comparison to being nonsuicidal.…

Mediating Effects of Coping, Personal Belief, and Social Support on the Relationship among Stress, Depression, and Smoking Behaviour in University Students

ERIC Educational Resources Information Center

Sun, Jing; Buys, Nicholas; Stewart, Donald; Shum, David

2011-01-01

Purpose: The purpose of this paper is to investigate whether university students' smoking behaviour is associated with higher levels of stress and depression directly, or indirectly, via the mediation of coping, personal beliefs and social support. Design/methodology/approach: The study design involves a cross-sectional survey. Structural equation…

A study of hydrocarbons associated with brines from DOE geopressured wells

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

Keeley, D.F.

1993-01-01

Accomplishments are summarized on the following tasks: distribution coefficients and solubilities, DOE design well sampling, analysis of well samples, review of theoretical models of geopressured reservoir hydrocarbons, monitor for aliphatic hydrocarbons, development of a ph meter probe, DOE design well scrubber analysis, removal and disposition of gas scrubber equipment at Pleasant Bayou Well, and disposition of archived brines.

Bioelectrochemical Systems Workshop:Standardized Analyses, Design Benchmarks, and Reporting

DTIC Science & Technology

2012-01-01

related to the exoelectrogenic biofilm activity, and to investigate whether the community structure is a function of design and operational parameters...where should biofilm samples be collected? The most prevalent methods of community characterization in BES studies have entailed phylogenetic ...of function associated with this genetic marker, and in methods that involve polymerase chain reaction (PCR) amplification the quantitative

The Trend-in-trend Research Design for Causal Inference.

PubMed

Ji, Xinyao; Small, Dylan S; Leonard, Charles E; Hennessy, Sean

2017-07-01

Cohort studies can be biased by unmeasured confounding. We propose a hybrid ecologic-epidemiologic design called the trend-in-trend design, which requires a strong time trend in exposure, but is unbiased unless there are unmeasured factors affecting outcome for which there are time trends in prevalence that are correlated with time trends in exposure across strata with different exposure trends. Thus, the conditions under which the trend-in-trend study is biased are a subset of those under which a cohort study is biased. The trend-in-trend design first divides the study population into strata based on the cumulative probability of exposure given covariates, which effectively stratifies on time trend in exposure, provided there is a trend. Next, a covariates-free maximum likelihood model estimates the odds ratio (OR) using data on exposure prevalence and outcome frequency within cumulative probability of exposure strata, across multiple periods. In simulations, the trend-in-trend design produced ORs with negligible bias in the presence of unmeasured confounding. In empiric applications, trend-in-trend reproduced the known positive association between rofecoxib and myocardial infarction (observed OR: 1.2, 95% confidence interval: 1.1, 1.4), and known null associations between rofecoxib and severe hypoglycemia (OR = 1.1 [0.92, 1.3]) and nonvertebral fracture (OR = 0.84 [0.64, 1.1]). The trend-in-trend method may be useful in settings where there is a strong time trend in exposure, such as a newly approved drug or other medical intervention. See video abstract at, http://links.lww.com/EDE/B178.

International Civic and Citizenship Education Study: Assessment Framework

ERIC Educational Resources Information Center

Schulz, Wolfram; Fraillon, Julian; Ainley, John; Losito, Bruno; Kerr, David

2008-01-01

This document outlines the framework and assessment design for the International Civic and Citizenship Education Study (ICCS) sponsored by the International Association for the Evaluation of Educational Achievement (IEA). Over the past 50 years, IEA has conducted comparative research studies focusing on educational policies, practices, and…

Parenting a Child with a Learning Disability: A Qualitative Approach

ERIC Educational Resources Information Center

Fernández-Alcántara, Manuel; Correa-Delgado, Cayetana; Muñoz, Ángela; Salvatierra, María Teresa; Fuentes-Hélices, Tadeo; Laynez-Rubio, Carolina

2017-01-01

The present study describes experiences associated with parenting children diagnosed with learning disabilities. Parents whose children were diagnosed with Attention Deficit Hyperactivity Disorder, dyslexia/language problems, and Asperger syndrome, related to poor performance at school, took part in the study. A qualitative study design was…

C[superscript 2] = BOK: Two Apparel Studies' Capstone Courses Incorporating the Body of Knowledge

ERIC Educational Resources Information Center

Smith, Kathleen R.; Apple, Laurie; Souhtward, Leigh

2014-01-01

Guided by the five cross-cutting themes of the American Association of Family & Consumer Sciences (AAFCS) Body of Knowledge (BOK) two capstone courses (C[superscript 2]) in Apparel Studies were designed to help prepare students for careers, further study, or both.

Inhalation of Photochemically Altered Urban Mixtures Depresses Cardiac Function in Mice

EPA Science Inventory

Rationale: Epidemiological studies have indicated an association between urban air pollution exposure and cardiovascular morbidity and mortality. The present study was designed to evaluate the cardiac effects of inhaled photochemical products in urban mixtures in a murine model. ...

Diesel Exhaust in Miners Study: Q&A

Cancer.gov

The Diesel Exhaust in Miners Study was designed to evaluate the risk of death associated with diesel exhaust exposure, particularly as it may relate to lung cancer. The researchers observed increased risk for lung cancer death with increasing levels of ex

Multiprocessor architectural study

NASA Technical Reports Server (NTRS)

Kosmala, A. L.; Stanten, S. F.; Vandever, W. H.

1972-01-01

An architectural design study was made of a multiprocessor computing system intended to meet functional and performance specifications appropriate to a manned space station application. Intermetrics, previous experience, and accumulated knowledge of the multiprocessor field is used to generate a baseline philosophy for the design of a future SUMC* multiprocessor. Interrupts are defined and the crucial questions of interrupt structure, such as processor selection and response time, are discussed. Memory hierarchy and performance is discussed extensively with particular attention to the design approach which utilizes a cache memory associated with each processor. The ability of an individual processor to approach its theoretical maximum performance is then analyzed in terms of a hit ratio. Memory management is envisioned as a virtual memory system implemented either through segmentation or paging. Addressing is discussed in terms of various register design adopted by current computers and those of advanced design.

Longitudinal Associations Between Marital Instability and Child Sleep Problems across Infancy and Toddlerhood in Adoptive Families

PubMed Central

Mannering, Anne M.; Harold, Gordon T.; Leve, Leslie D.; Shelton, Katherine H.; Shaw, Daniel S.; Conger, Rand D.; Neiderhiser, Jenae M.; Scaramella, Laura V.; Reiss, David

2009-01-01

This study examined the longitudinal association between marital instability and child sleep problems at ages 9 and 18 months in 357 families with a genetically unrelated infant adopted at birth. This design eliminates shared genes as an explanation for similarities between parent and child. Structural equation modeling indicated that T1 marital instability predicted T2 child sleep problems, but T1 child sleep problems did not predict T2 marital instability. This pattern of results was replicated when models were estimated separately for mothers and children and for fathers and children. Thus, even after controlling for stability in sleep problems and marital instability and eliminating shared genetic influences on associations using a longitudinal adoption design, marital instability prospectively predicts early childhood sleep patterns. PMID:21557740

Childhood brain tumour risk and its association with wireless phones: a commentary

PubMed Central

2011-01-01

Case-control studies on adults point to an increased risk of brain tumours (glioma and acoustic neuroma) associated with the long-term use of mobile phones. Recently, the first study on mobile phone use and the risk of brain tumours in children and adolescents, CEFALO, was published. It has been claimed that this relatively small study yielded reassuring results of no increased risk. We do not agree. We consider that the data contain several indications of increased risk, despite low exposure, short latency period, and limitations in the study design, analyses and interpretation. The information certainly cannot be used as reassuring evidence against an association, for reasons that we discuss in this commentary. PMID:22182218

Childhood brain tumour risk and its association with wireless phones: a commentary.

PubMed

Söderqvist, Fredrik; Carlberg, Michael; Hansson Mild, Kjell; Hardell, Lennart

2011-12-19

Case-control studies on adults point to an increased risk of brain tumours (glioma and acoustic neuroma) associated with the long-term use of mobile phones. Recently, the first study on mobile phone use and the risk of brain tumours in children and adolescents, CEFALO, was published. It has been claimed that this relatively small study yielded reassuring results of no increased risk. We do not agree. We consider that the data contain several indications of increased risk, despite low exposure, short latency period, and limitations in the study design, analyses and interpretation. The information certainly cannot be used as reassuring evidence against an association, for reasons that we discuss in this commentary.

Integrated technology wing design study

NASA Technical Reports Server (NTRS)

Hays, A. P.; Beck, W. E.; Morita, W. H.; Penrose, B. J.; Skarshaug, R. E.; Wainfan, B. S.

1984-01-01

The technology development costs and associated benefits in applying advanced technology associated with the design of a new wing for a new or derivative trijet with a capacity for 350 passengers and maximum range of 8519 km, entering service in 1990 were studied. The areas of technology are: (1) airfoil technology; (2) planform parameters; (3) high lift; (4) pitch active control system; (5) all electric systems; (6) E to 3rd power propulsion; (7) airframe/propulsion integration; (8) graphite/epoxy composites; (9) advanced aluminum alloys; (10) titanium alloys; and (11) silicon carbide/aluminum composites. These technologies were applied to the reference aircraft configuration. Payoffs were determined for block fuel reductions and net value of technology. These technologies are ranked for the ratio of net value of technology (NVT) to technology development costs.

In search of causality: a systematic review of the relationship between the built environment and physical activity among adults

PubMed Central

2011-01-01

Background Empirical evidence suggests that an association between the built environment and physical activity exists. This evidence is mostly derived from cross-sectional studies that do not account for other causal explanations such as neighborhood self-selection. Experimental and quasi-experimental designs can be used to isolate the effect of the built environment on physical activity, but in their absence, statistical techniques that adjust for neighborhood self-selection can be used with cross-sectional data. Previous reviews examining the built environment-physical activity relationship have not differentiated among findings based on study design. To deal with self-selection, we synthesized evidence regarding the relationship between objective measures of the built environment and physical activity by including in our review: 1) cross-sectional studies that adjust for neighborhood self-selection and 2) quasi-experiments. Method In September 2010, we searched for English-language studies on built environments and physical activity from all available years in health, leisure, transportation, social sciences, and geographical databases. Twenty cross-sectional and 13 quasi-experimental studies published between 1996 and 2010 were included in the review. Results Most associations between the built environment and physical activity were in the expected direction or null. Land use mix, connectivity and population density and overall neighborhood design were however, important determinants of physical activity. The built environment was more likely to be associated with transportation walking compared with other types of physical activity including recreational walking. Three studies found an attenuation in associations between built environment characteristics and physical activity after accounting for neighborhood self-selection. Conclusion More quasi-experiments that examine a broader range of environmental attributes in relation to context-specific physical activity and that measure changes in the built environment, neighborhood preferences and their effect on physical activity are needed. PMID:22077952

A Children of Twins Study of parental divorce and offspring psychopathology.

PubMed

D'Onofrio, Brian M; Turkheimer, Eric; Emery, Robert E; Maes, Hermine H; Silberg, Judy; Eaves, Lindon J

2007-07-01

Although parental divorce is associated with increased substance use and internalizing problems, experiencing the separation of one's parents may not cause these outcomes. The relations may be due to genetic or environmental selection factors, characteristics that lead to both marital separation and offspring functioning. We used the Children of Twins (CoT) Design to explore whether unmeasured genetic or environmental factors related to the twin parent, and measured characteristics of both parents, account for the association between parental divorce and offspring substance use and internalizing problems. The association between parental divorce and offspring substance use problems remained robust when controlling for genetic and environmental risk from the twin parent associated with parental divorce, and measured characteristics of both parents. The results do not prove, but are consistent with, a causal connection. In contrast, the analyses suggest that shared genetic liability in parents and their offspring accounts for the increased risk of internalizing problems in adult offspring from divorced families. The study illustrates that unmeasured genetic and environmental selection factors must be considered when studying parental divorce. In explaining associations between parental divorce and young-adult adjustment, our evidence suggests that selection versus causal mechanisms may operate differently for substance abuse (a causal relation) and internalizing problems (an artifact of selection). The CoT design only controls for the genetic and environmental characteristics of one parent; thus, additional genetically informed analyses are needed.

Obsessive-compulsive symptoms and personal disposition, family coherence and school environment in Chinese adolescents: a resilience approach.

PubMed

Sun, Jing; Li, Zhan-Jiang; Buys, Nicholas J; Storch, Eric A; Wang, Ji-sheng

2014-10-01

Risk factors of adolescents with obsessive-compulsive symptoms (OC) have been extensively examined, but protective resilience factors have not been explored, particularly in Chinese adolescents. This study aimed to investigate the association of resilience factors with the occurrence of OC and its symptoms in Chinese adolescents. This study consisted of two phases. The first phase used a cross-sectional design involving a stratified clustered non-clinical sample of 3185 secondary school students. A clinical interview procedure was then employed to diagnose OC in students who had a Leyton Obsessional Inventory 'yes' score of ≥15. The second phase used a case-control study design to analyse the relationship between resilience factors and OC in a matched sample of 288 adolescents with diagnosed OC relative to 246 healthy adolescents. Low personal disposition scores in self-fulfilment, flexibility and self-esteem, and low peer relation scores in the school environment were associated with a higher probability of having OC. Canonical correlation analysis indicated that OC symptoms were significantly associated with personal dispositions, poor peer relationships and maladaptive social life, but not to family coherence. The study is not prospective in nature, so the causal relationship between OC occurrence and resilience factors cannot be confirmed. Second, the use of self-report instruments in personal disposition, family coherence, and school environment may be a source of error. Resilience factors at both the personal disposition and school environment levels are important predictors of OC symptoms and caseness. Future studies using prospective designs are needed to confirm these relationships. Copyright © 2014 Elsevier B.V. All rights reserved.

Current Parental Depression and Offspring Perceived Self-Competence: A Quasi-Experimental Examination

PubMed Central

Class, Quetzal A.; D’Onofrio, Brian M.; Singh, Amber L.; Ganiban, Jody M.; Spotts, E. L.; Lichtenstein, Paul; Reiss, David; Neiderhiser, Jenae M.

2013-01-01

A genetically-informed, quasi-experimental design was used to examine the genetic and environmental processes underlying associations between current parental depressive symptoms and offspring perceived self-competence. Participants, drawn from a population-based Swedish sample, were 852 twin pairs and their male (52%) and female offspring aged 15.7 ± 2.4 years. Parental depressive symptoms were measured using the Center for Epidemiological Studies Depression scale. Offspring perceived self-competence was measured using a modified Harter Perceived Competence Scale. Cousin comparisons and Children of Twins (CoT) designs suggested that associations between maternal depressive symptoms and offspring perceived self-competence were due to shared genetic/environmental liability. The mechanism responsible for father-offspring associations, however, was independent of genetic factors and of extended-family environmental factors, supporting a causal inference. Thus, mothers and fathers may impact offspring perceived self-competence via different mechanisms and unmeasured genetic and environmental selection factors must be considered when studying the intergenerational transmission of cognitive vulnerabilities for depression. PMID:22692226

Current parental depression and offspring perceived self-competence: a quasi-experimental examination.

PubMed

Class, Quetzal A; D'Onofrio, Brian M; Singh, Amber L; Ganiban, Jody M; Spotts, E L; Lichtenstein, Paul; Reiss, David; Neiderhiser, Jenae M

2012-09-01

A genetically-informed, quasi-experimental design was used to examine the genetic and environmental processes underlying associations between current parental depressive symptoms and offspring perceived self-competence. Participants, drawn from a population-based Swedish sample, were 852 twin pairs and their male (52 %) and female offspring aged 15.7 ± 2.4 years. Parental depressive symptoms were measured using the Center for Epidemiological Studies Depression scale. Offspring perceived self-competence was measured using a modified Harter Perceived Competence Scale. Cousin comparisons and Children of Twins designs suggested that associations between maternal depressive symptoms and offspring perceived self-competence were due to shared genetic/environmental liability. The mechanism responsible for father-offspring associations, however, was independent of genetic factors and of extended family environmental factors, supporting a causal inference. Thus, mothers and fathers may impact offspring perceived self-competence via different mechanisms and unmeasured genetic and environmental selection factors must be considered when studying the intergenerational transmission of cognitive vulnerabilities for depression.

Maternal smoking during pregnancy and offspring conduct problems: Evidence from three independent genetically-sensitive research designs

PubMed Central

Gaysina, Darya; Fergusson, David M.; Leve, Leslie D.; Horwood, John; Reiss, David; Shaw, Daniel S.; Elam, Kit K.; Natsuaki, Misaki N.; Neiderhiser, Jenae M.; Harold, Gordon T.

2013-01-01

Context A number of studies report an association between maternal smoking during pregnancy and offspring conduct disorder. However, past research evidences difficulty disaggregating prenatal environmental from genetic and postnatal environmental influences. Objective To examine the relationship between maternal smoking during pregnancy and offspring conduct problems among children reared by genetically-related and genetically-unrelated mothers. Design, Setting and Participants Three studies employing distinct but complementary research designs were utilized: The Christchurch Health and Development Study (a longitudinal cohort study that includes biological and adopted children), the Early Growth and Development Study (a longitudinal adoption at birth study), and the Cardiff IVF Study (genetically-related and -unrelated families; an adoption at conception study). Maternal smoking during pregnancy was measured as the average number of cigarettes/day (0, 1–9 or 10+) smoked during pregnancy. A number of possible covariates (child gender, ethnicity, birth weight, breast feeding, maternal age at birth, maternal education, family SES, family breakdown, placement age, and parenting practices) were controlled in the analyses. Main Outcome Measure Child conduct problems (age 4–10 years) reported by parents and/or teachers using the Rutter and Conners behaviour scales, the Child Behavior Checklist and Children's Behavior Questionnaire, and the Strengths and Difficulties Questionnaire. Results A significant association between maternal smoking during pregnancy and child conduct problems was observed among children reared by genetically-related and genetically-unrelated mothers. Results from a meta-analysis affirmed this pattern of findings across pooled study samples. Conclusions Findings across the three studies using a complement of genetically-sensitive research designs suggest smoking during pregnancy is a prenatal risk factor for offspring conduct problems, when specific perinatal and postnatal confounding factors are controlled. PMID:23884431

Distracted Driving and Risk of Crash or Near-crash Involvement among Older Drivers using Naturalistic Driving Data with a Case-crossover Study Design.

PubMed

Huisingh, Carrie; Owsley, Cynthia; Levitan, Emily B; Irvin, Marguerite R; MacLennan, Paul; McGwin, Gerald

2018-05-17

The purpose of this study was to examine the association between secondary task involvement and risk of crash and near-crash involvement among older drivers using naturalistic driving data. Data from drivers aged ≥70 years in the Strategic Highway Research Program (SHRP2) Naturalistic Driving Study database was utilized. The personal vehicle of study participants was equipped with four video cameras enabling recording of the driver and the road environment. Secondary task involvement during a crash or near-crash event was compared to periods of non-crash involvement in a case-crossover study design. Conditional logistic regression was used to generate odds ratios (OR) and 95% confidence intervals (CI). Overall, engaging in any secondary task was not associated with crash (OR=0.94, 95% CI 0.68-1.29) or near-crash (OR=1.08, 95% CI 0.79-1.50) risk. The risk of a major crash event with cell phone use was 3.79 times higher than the risk with no cell phone use (95% CI 1.00-14.37). Other glances into the interior of the vehicle were associated with an increased risk of near-crash involvement (OR=2.55, 95% CI 1.24-5.26). Other distractions external to the vehicle were associated with a decreased risk of crash involvement (OR=0.53, 95% CI 0.30-0.94). Interacting with a passenger and talking/singing were not associated with crash or near-crash risk. Older drivers should avoid any cell phone use and minimize non-driving related eye glances towards the interior of the vehicle while driving. Certain types of events external to the vehicle are associated with a reduced crash risk among older drivers.

The Effects of General System Justification on Corruption Perception and Intent

PubMed Central

Tan, Xuyun; Liu, Li; Huang, Zhenwei; Zheng, Wenwen; Liang, Yuan

2016-01-01

Previous research stresses that system justifying belief can weaken corruption perception, by this possibly fostering unjust behaviors. However, general results of the effect of general system justification on corruption are ambiguous, indicating also a lessening impact. We conducted a line of studies trying to elucidate these circumstances by testing the effect of general system justification on corruption perception and intention. In addition, we explored institutional trust as a possible mediator in this process. For this purpose, we conducted three studies. The first two studies examined the association between general system justification and corruption. In Study 1, a correlational design was run using questionnaires to assess the relation between general system justification and corruption perception as well as corruption intention. In Study 2, an experimental design was conducted manipulating general system justification via exposure to high or low system threat condition, then measuring its effect on corruption perception and corrupt intention. In Study 3, two sub-studies using correlational and experimental designs were run to explore the mediating role of institutional trust, respectively. Results replicated former studies showing that general system justification is negatively associated with corruption perception. However, they also showed a negative correlation with corrupt intention. Furthermore, they showed that institutional trust mediated the relation between general system justification and corruption. We suggest to consider these findings to further elucidate the psychological basis underlying different effects of general system justification on human behaviors. PMID:27507954

The Effects of General System Justification on Corruption Perception and Intent.

PubMed

Tan, Xuyun; Liu, Li; Huang, Zhenwei; Zheng, Wenwen; Liang, Yuan

2016-01-01

Previous research stresses that system justifying belief can weaken corruption perception, by this possibly fostering unjust behaviors. However, general results of the effect of general system justification on corruption are ambiguous, indicating also a lessening impact. We conducted a line of studies trying to elucidate these circumstances by testing the effect of general system justification on corruption perception and intention. In addition, we explored institutional trust as a possible mediator in this process. For this purpose, we conducted three studies. The first two studies examined the association between general system justification and corruption. In Study 1, a correlational design was run using questionnaires to assess the relation between general system justification and corruption perception as well as corruption intention. In Study 2, an experimental design was conducted manipulating general system justification via exposure to high or low system threat condition, then measuring its effect on corruption perception and corrupt intention. In Study 3, two sub-studies using correlational and experimental designs were run to explore the mediating role of institutional trust, respectively. Results replicated former studies showing that general system justification is negatively associated with corruption perception. However, they also showed a negative correlation with corrupt intention. Furthermore, they showed that institutional trust mediated the relation between general system justification and corruption. We suggest to consider these findings to further elucidate the psychological basis underlying different effects of general system justification on human behaviors.

The Association between Prenatal Cocaine Exposure and Physiological Regulation at 13 Months of Age

ERIC Educational Resources Information Center

Schuetze, Pamela; Eiden, Rina D.; Danielewicz, Susan

2009-01-01

Background: This study examined the association between prenatal cocaine exposure (PCE) and autonomic regulation at 13 months of age. Methods: Measures of respiratory sinus arrhythmia (RSA) were obtained from 156 (79 exposed, and 77 nonexposed) infants during baseline and during tasks designed to elicit positive (PA) and negative affect (NA).…

The Relationships between Brand Association, Trust, Commitment, and Satisfaction of Higher Education Institutions

ERIC Educational Resources Information Center

Chen, Yu-Chuan

2017-01-01

Purpose: The purpose of this paper is to explore structural relationships among the variables of brand association, student trust, commitment, and satisfaction in the higher education sector. Design/methodology/approach: A survey was used to collect data from a sample of 500 students who studied at universities in Taiwan in 2016. These data were…

Technical Preparation: Preparing Students for Success. A Position Paper Presented by the Wisconsin Association of Secondary Vocational Administrators 1991-1992.

ERIC Educational Resources Information Center

Peterson, Charlene; And Others

Technical Preparation (Tech Prep) programs include basic skills and competencies to improve students' school-to-work transition. The following elements characterize Tech Prep: designed for grades 9-14, leading to an technical associate degree; parallels college preparatory program; offers technical program of study in business enterprise,…

NGIPS Early Design Space Assessment

DTIC Science & Technology

2014-07-17

medium - voltage dc ( MVDC ) shipboard power system are described below. These studies pursue the questions posed in the white paper. In...usna.edu Abstract—Short-circuit protection is one of the greatest risks associated with a transition towards medium - voltage dc ( MVDC ) shipboard power...protection is one of the greatest risks associated with a transition towards medium - voltage dc ( MVDC ) shipboard power

Physical and Cognitive-Affective Factors Associated with Fatigue in Individuals with Fibromyalgia: A Multiple Regression Analysis

ERIC Educational Resources Information Center

Muller, Veronica; Brooks, Jessica; Tu, Wei-Mo; Moser, Erin; Lo, Chu-Ling; Chan, Fong

2015-01-01

Purpose: The main objective of this study was to determine the extent to which physical and cognitive-affective factors are associated with fibromyalgia (FM) fatigue. Method: A quantitative descriptive design using correlation techniques and multiple regression analysis. The participants consisted of 302 members of the National Fibromyalgia &…

Tracing Differential Pathways of Risk: Associations among Family Adversity, Cortisol, and Cognitive Functioning in Childhood

ERIC Educational Resources Information Center

Suor, Jennifer H.; Sturge-Apple, Melissa L.; Davies, Patrick T.; Cicchetti, Dante; Manning, Liviah G.

2015-01-01

Guided by family risk and allostasis theoretical frameworks, the present study utilized a prospective longitudinal design to examine associations among family risk experiences, basal cortisol patterns, and cognitive functioning in children. The sample included 201 low-income children living within a midsize city in the Northeastern United States.…

Interrelations in Children's Learning of Verbal and Pictorial Paired Associates.

ERIC Educational Resources Information Center

Hale, Gordon A.

This study was designed to investigate the functional similarity of the mental processes children use to learn verbal tasks and pictorial tasks. Children in grades 3 and 6 (n=144) and in grade 9 (n=112) were given four short paired-associate tasks entitled Pictures, Concrete Words, Abstract Words, and Japanese Characters. The tasks consisted of…

Leadership Styles of Nursing Home Administrators and Their Association with Staff Turnover

ERIC Educational Resources Information Center

Donoghue, Christopher; Castle, Nicholas G.

2009-01-01

Purpose: The purpose of this study was to examine the associations between nursing home administrator (NHA) leadership style and staff turnover. Design and Methods: We analyzed primary data from a survey of 2,900 NHAs conducted in 2005. The Online Survey Certification and Reporting database and the Area Resource File were utilized to extract…

Prospective study of tricuspid valve regurgitation associated with permanent leads in patients undergoing cardiac rhythm device implantation: Background, rationale, and design

PubMed Central

Dokainish, Hisham; Elbarasi, Esam; Masiero, Simona; Van de Heyning, Caroline; Brambatti, Michela; Ghazal, Sami; AL-Maashani, Said; Capucci, Alessandro; Buikema, Lisanne; Leong, Darryl; Shivalkar, Bharati; Saenen, Johan; Miljoen, Hielko; Morillo, Carlos; Divarakarmenon, Syam; Amit, Guy; Ribas, Sebastian; Brautigam, Aaron; Baiocco, Erika; Maolo, Alessandro; Romandini, Andrea; Maffei, Simone; Connolly, Stuart; Healey, Jeff

2015-01-01

Given the increasing numbers of cardiac device implantations worldwide, it is important to determine whether permanent endocardial leads across the tricuspid valve can promote tricuspid regurgitation (TR). Virtually all current data is retrospective, and indicates a signal of TR being increased after permanent lead implantation. However, the precise incidence of moderate or greater TR post-procedure, the exact mechanisms (mechanical, traumatic, functional), and the hemodynamic burden and clinical effects of this putative increase in TR, remain uncertain. We have therefore designed a multicenter, international, prospective study of 300 consecutive patients (recruitment completed, baseline data presented) who will undergo echocardiography and clinical assessment prior to, and at 1-year post device insertion. This prospective study will help determine whether cardiac device-associated TR is real, what are its potential mechanisms, and whether it has an important clinical impact on cardiac device patients. PMID:26779517

History and Impact of Nutritional Epidemiology123

PubMed Central

Alpers, David H.; Bier, Dennis M.; Carpenter, Kenneth J.; McCormick, Donald B.; Miller, Anthony B.; Jacques, Paul F.

2014-01-01

The real and important role of epidemiology was discussed, noting heretofore unknown associations that led to improved understanding of the cause and prevention of individual nutritional deficiencies. However, epidemiology has been less successful in linking individual nutrients to the cause of chronic diseases, such as cancer and cardiovascular disease. Dietary changes, such as decreasing caloric intake to prevent cancer and the Mediterranean diet to prevent diabetes, were confirmed as successful approaches to modifying the incidence of chronic diseases. The role of the epidemiologist was confirmed as a collaborator, not an isolated expert of last resort. The challenge for the future is to decide which epidemiologic methods and study designs are most useful in studying chronic disease, then to determine which associations and the hypotheses derived from them are especially strong and worthy of pursuit, and finally to design randomized studies that are feasible, affordable, and likely to result in confirmation or refutation of these hypotheses. PMID:25469385

Personalized Risk Estimator for Rheumatoid Arthritis (PRE-RA) Family Study: rationale and design for a randomized controlled trial evaluating rheumatoid arthritis risk education to first-degree relatives.

PubMed

Sparks, Jeffrey A; Iversen, Maura D; Miller Kroouze, Rachel; Mahmoud, Taysir G; Triedman, Nellie A; Kalia, Sarah S; Atkinson, Michael L; Lu, Bing; Deane, Kevin D; Costenbader, Karen H; Green, Robert C; Karlson, Elizabeth W

2014-09-01

We present the rationale, design features, and protocol of the Personalized Risk Estimator for Rheumatoid Arthritis (PRE-RA) Family Study (ClinicalTrials.gov NCT02046005). The PRE-RA Family Study is an NIH-funded prospective, randomized controlled trial designed to compare the willingness to change behaviors in first-degree relatives of rheumatoid arthritis (RA) patients without RA after exposure to RA risk educational programs. Consented subjects are randomized to receive education concerning their personalized RA risk based on demographics, RA-associated behaviors, genetics, and biomarkers or to receive standard RA information. Four behavioral factors associated with RA risk were identified from prior studies for inclusion in the risk estimate: cigarette smoking, excess body weight, poor oral health, and low fish intake. Personalized RA risk information is presented through an online tool that collects data on an individual's specific age, gender, family history, and risk-related behaviors; presents genetic and biomarker results; displays relative and absolute risk of RA; and provides personalized feedback and education. The trial outcomes will be changes in willingness to alter behaviors from baseline to 6 weeks, 6 months, and 12 months in the three intervention groups. The design and the execution of this trial that targets a special population at risk for RA, while incorporating varied risk factors into a single risk tool, offer distinct challenges. We provide the theoretical rationale for the PRE-RA Family Study and highlight particular design features of this trial that utilize personalized risk education as an intervention. Copyright © 2014 Elsevier Inc. All rights reserved.

Placebo influences on dyskinesia in Parkinson's disease.

PubMed

Goetz, Christopher G; Laska, Eugene; Hicking, Christine; Damier, Philippe; Müller, Thomas; Nutt, John; Warren Olanow, C; Rascol, Olivier; Russ, Hermann

2008-04-15

Clinical features that are prognostic indicators of placebo response among dyskinetic Parkinson's disease patients were determined. Placebo-associated improvements occur in Parkinsonism, but responses in dyskinesia have not been studied. Placebo data from two multicenter studies with identical design comparing sarizotan to placebo for treating dyskinesia were accessed. Sarizotan (2 mg/day) failed to improve dyskinesia compared with placebo, but both treatments improved dyskinesia compared with baseline. Stepwise regression identified baseline characteristics that influenced dyskinesia response to placebo, and these factors were entered into a logistic regression model to quantify their influence on placebo-related dyskinesia improvements and worsening. Because placebo-associated improvements in Parkinsonism have been attributed to heightened dopaminergic activity, we also examined the association between changes in Parkinsonism and dyskinesia. Four hundred eighty-four subjects received placebo treatment; 178 met criteria for placebo-associated dyskinesia improvement and 37 for dyskinesia worsening. Older age, lower baseline Parkinsonism score, and lower total daily levodopa doses were associated with placebo-associated improvement, whereas lower baseline dyskinesia score was associated with placebo-associated worsening. Placebo-associated dyskinesia changes were not correlated with Parkinsonism changes, and all effects in the sarizotan group were statistically explained by the placebo-effect regression model. Dyskinesias are affected by placebo treatment. The absence of correlation between placebo-induced changes in dyskinesia and Parkinsonism argues against a dopaminergic activation mechanism to explain placebo-associated improvements in dyskinesia. The magnitude and variance of placebo-related changes and the factors that influence them can be helpful in the design of future clinical trials of antidyskinetic agents. 2007 Movement Disorder Society

Placebo Influences on Dyskinesia in Parkinson's Disease

PubMed Central

Goetz, Christopher G.; Laska, Eugene; Hicking, Christine; Damier, Philippe; Müller, Thomas; Nutt, John; Olanow, C. Warren; Rascol, Olivier; Russ, Hermann

2009-01-01

Clinical features that are prognostic indicators of placebo response among dyskinetic Parkinson's disease patients were determined. Placebo-associated improvements occur in Parkinsonism, but responses in dyskinesia have not been studied. Placebo data from two multicenter studies with identical design comparing sarizotan to placebo for treating dyskinesia were accessed. Sarizotan (2 mg/day) failed to improve dyskinesia compared with placebo, but both treatments improved dyskinesia compared with baseline. Stepwise regression identified baseline characteristics that influenced dyskinesia response to placebo, and these factors were entered into a logistic regression model to quantify their influence on placebo-related dyskinesia improvements and worsening. Because placebo-associated improvements in Parkinsonism have been attributed to heightened dopaminergic activity, we also examined the association between changes in Parkinsonism and dyskinesia. Four hundred eighty-four subjects received placebo treatment; 178 met criteria for placebo-associated dyskinesia improvement and 37 for dyskinesia worsening. Older age, lower baseline Parkinsonism score, and lower total daily levodopa doses were associated with placebo-associated improvement, whereas lower baseline dyskinesia score was associated with placebo-associated worsening. Placebo-associated dyskinesia changes were not correlated with Parkinsonism changes, and all effects in the sarizotan group were statistically explained by the placebo-effect regression model. Dyskinesias are affected by placebo treatment. The absence of correlation between placebo-induced changes in dyskinesia and Parkinsonism argues against a dopaminergic activation mechanism to explain placebo-associated improvements in dyskinesia. The magnitude and variance of placebo-related changes and the factors that influence them can be helpful in the design of future clinical trials of antidyskinetic agents. PMID:18175337

Employment and the associated impact on quality of life in people diagnosed with schizophrenia.

PubMed

Bouwmans, Clazien; de Sonneville, Caroline; Mulder, Cornelis L; Hakkaart-van Roijen, Leona

2015-01-01

A systematic review was conducted to assess the employment rate of people with schizophrenia. Additionally, information from the selected studies concerning factors associated with employment and health-related quality of life (HRQoL) was examined. Employment rates ranged from 4% to 50.4%. The studies differed considerably in design, patient settings, and methods of recruitment. The most frequently reported factors associated with employment were negative and cognitive symptoms, age of onset, and duration and course of the disease. Individual characteristics associated with unemployment were older age, lower education, and sex (female). Additionally, environmental factors, eg, the availability of welfare benefits and vocational support programs, seemed to play a role. Generally, being employed was positively associated with HRQoL. However, the causal direction of this association remained unclear, as studies on the bidirectional relationship between employment and HRQoL were lacking.

Sexual Assault and Sexual Harassment in the U.S. Military. Volume 1. Design of the 2014 RAND Military Workplace Study

DTIC Science & Technology

2014-01-01

studies need to examine whether nonresponse bias remains in survey estimates. Even a comparatively small nonresponse rate could, in theory , lead to...gathering and maintaining the data needed , and completing and reviewing the collection of information. Send comments regarding this burden estimate or any...crimes in Article 120 need not be associated with sexual gratification if they are designed to humiliate or debase the person who is assaulted. Instead

XPAT: a toolkit to conduct cross-platform association studies with heterogeneous sequencing datasets.

PubMed

Yu, Yao; Hu, Hao; Bohlender, Ryan J; Hu, Fulan; Chen, Jiun-Sheng; Holt, Carson; Fowler, Jerry; Guthery, Stephen L; Scheet, Paul; Hildebrandt, Michelle A T; Yandell, Mark; Huff, Chad D

2018-04-06

High-throughput sequencing data are increasingly being made available to the research community for secondary analyses, providing new opportunities for large-scale association studies. However, heterogeneity in target capture and sequencing technologies often introduce strong technological stratification biases that overwhelm subtle signals of association in studies of complex traits. Here, we introduce the Cross-Platform Association Toolkit, XPAT, which provides a suite of tools designed to support and conduct large-scale association studies with heterogeneous sequencing datasets. XPAT includes tools to support cross-platform aware variant calling, quality control filtering, gene-based association testing and rare variant effect size estimation. To evaluate the performance of XPAT, we conducted case-control association studies for three diseases, including 783 breast cancer cases, 272 ovarian cancer cases, 205 Crohn disease cases and 3507 shared controls (including 1722 females) using sequencing data from multiple sources. XPAT greatly reduced Type I error inflation in the case-control analyses, while replicating many previously identified disease-gene associations. We also show that association tests conducted with XPAT using cross-platform data have comparable performance to tests using matched platform data. XPAT enables new association studies that combine existing sequencing datasets to identify genetic loci associated with common diseases and other complex traits.

Understanding the Relationship between Activity and Neighbourhoods (URBAN) Study: research design and methodology.

PubMed

Badland, Hannah M; Schofield, Grant M; Witten, Karen; Schluter, Philip J; Mavoa, Suzanne; Kearns, Robin A; Hinckson, Erica A; Oliver, Melody; Kaiwai, Hector; Jensen, Victoria G; Ergler, Christina; McGrath, Leslie; McPhee, Julia

2009-07-10

Built environment attributes are recognized as being important contributors to physical activity (PA) engagement and body size in adults and children. However, much of the existing research in this emergent public health field is hindered by methodological limitations, including: population and site homogeneity, reliance on self-report measures, aggregated measures of PA, and inadequate statistical modeling. As an integral component of multi-country collaborative research, the Understanding the Relationship between Activity and Neighbourhoods (URBAN) Study seeks to overcome these limitations by determining the strengths of association between detailed measures of the neighborhood built environment with PA levels across multiple domains and body size measures in adults and children. This article outlines the research protocol developed for the URBAN Study. The URBAN Study is a multi-centered, stratified, cross-sectional research design, collecting data across four New Zealand cities. Within each city, 12 neighborhoods were identified and selected for investigation based on higher or lower walkability and Māori demographic attributes. Neighborhoods were selected to ensure equal representation of these characteristics. Within each selected neighborhood, 42 households are being randomly selected and an adult and child (where possible) recruited into the study. Data collection includes: objective and self-reported PA engagement, neighborhood perceptions, demographics, and body size measures. The study was designed to recruit approximately 2,000 adults and 250 children into the project. Other aspects of the study include photovoice, which is a qualitative assessment of built environment features associated with PA engagement, an audit of the neighborhood streetscape environment, and an individualized neighborhood walkability profile centered on each participant's residential address. Multilevel modeling will be used to examine the individual-level and neighborhood-level relationships with PA engagement and body size. The URBAN Study is applying a novel scientifically robust research design to provide urgently needed epidemiological information regarding the associations between the built environment and health outcomes. The findings will contribute to a larger, international initiative in which similar neighborhood selection and PA measurement procedures are utilized across eight countries. Accordingly, this study directly addresses the international priority issues of increasing PA engagement and decreasing obesity levels.

Flavonoids, Flavonoid Subclasses, and Esophageal Cancer Risk: A Meta-Analysis of Epidemiologic Studies.

PubMed

Cui, Lingling; Liu, Xinxin; Tian, Yalan; Xie, Chen; Li, Qianwen; Cui, Han; Sun, Changqing

2016-06-08

Flavonoids have been suggested to play a chemopreventive role in carcinogenesis. However, the epidemiologic studies assessing dietary intake of flavonoids and esophageal cancer risk have yielded inconsistent results. This study was designed to examine the association between flavonoids, each flavonoid subclass, and the risk of esophageal cancer with a meta-analysis approach. We searched for all relevant studies with a prospective cohort or case-control study design published from January 1990 to April 2016, using PUBMED, EMBASE, and Web of Science. Pooled odds ratios (ORs) were calculated using fixed or random-effect models. In total, seven articles including 2629 cases and 481,193 non-cases were selected for the meta-analysis. Comparing the highest-intake patients with the lowest-intake patients for total flavonoids and for each flavonoid subclass, we found that anthocyanidins (OR = 0.60, 95% CI: 0.49-0.74), flavanones (OR = 0.65, 95% CI: 0.49-0.86), and flavones (OR = 0.78, 95% CI 0.64-0.95) were inversely associated with the risk of esophageal cancer. However, total flavonoids showed marginal association with esophageal cancer risk (OR = 0.78, 95% CI: 0.59-1.04). In conclusion, our study suggested that dietary intake of total flavonoids, anthocyanidins, flavanones, and flavones might reduce the risk of esophageal cancer.

Sleep quality and temperament among university students: differential associations with nighttime sleep duration and sleep disruptions.

PubMed

Lukowski, Angela F; Milojevich, Helen M

2015-01-01

Sleep-temperament associations have not yet been examined among university students, despite awareness of the high incidence of sleep problems in this population. The present study was conducted (a) to examine whether sleep quality was associated with temperament among university-attending young adults and (b) to determine whether particular components of sleep quality were differentially associated with temperament. University students completed questionnaires designed to assess sleep quality and temperament. Poor sleep quality was associated with increased negative affect and orienting sensitivity as well as decreased effortful control; regression analyses revealed differential associations between components of nighttime sleep quality and temperament ratings. The presented study reveals conceptual continuity in sleep-temperament relations from infancy to young adulthood and highlights important avenues for future research.

A two-stage design for multiple testing in large-scale association studies.

PubMed

Wen, Shu-Hui; Tzeng, Jung-Ying; Kao, Jau-Tsuen; Hsiao, Chuhsing Kate

2006-01-01

Modern association studies often involve a large number of markers and hence may encounter the problem of testing multiple hypotheses. Traditional procedures are usually over-conservative and with low power to detect mild genetic effects. From the design perspective, we propose a two-stage selection procedure to address this concern. Our main principle is to reduce the total number of tests by removing clearly unassociated markers in the first-stage test. Next, conditional on the findings of the first stage, which uses a less stringent nominal level, a more conservative test is conducted in the second stage using the augmented data and the data from the first stage. Previous studies have suggested using independent samples to avoid inflated errors. However, we found that, after accounting for the dependence between these two samples, the true discovery rate increases substantially. In addition, the cost of genotyping can be greatly reduced via this approach. Results from a study of hypertriglyceridemia and simulations suggest the two-stage method has a higher overall true positive rate (TPR) with a controlled overall false positive rate (FPR) when compared with single-stage approaches. We also report the analytical form of its overall FPR, which may be useful in guiding study design to achieve a high TPR while retaining the desired FPR.

Background and design of the profiling biobehavioral responses to mechanical support in advanced heart failure study.

PubMed

Lee, Christopher S; Mudd, James O; Gelow, Jill M; Nguyen, Thuan; Hiatt, Shirin O; Green, Jennifer K; Denfeld, Quin E; Bidwell, Julie T; Grady, Kathleen L

2014-01-01

Unexplained heterogeneity in response to ventricular assist device (VAD) implantation for the management of advanced heart failure impedes our ability to predict favorable outcomes, provide adequate patient and family education, and personalize monitoring and symptom management strategies. The purpose of this article was to describe the background and the design of a study entitled "Profiling Biobehavioral Responses to Mechanical Support in Advanced Heart Failure" (PREMISE). PREMISE is a prospective cohort study designed to (1) identify common and distinct trajectories of change in physical and psychological symptom burden; (2) characterize common trajectories of change in serum biomarkers of myocardial stress, systemic inflammation, and endothelial dysfunction; and (3) quantify associations between symptoms and biomarkers of pathogenesis in adults undergoing VAD implantation. Latent growth mixture modeling, including parallel process and cross-classification modeling, will be used to address the study aims and will entail identifying trajectories, quantifying associations between trajectories and both clinical and quality-of-life outcomes, and identifying predictors of favorable symptom and biomarker responses to VAD implantation. Research findings from the PREMISE study will be used to enhance shared patient and provider decision making and to shape a much-needed new breed of interventions and clinical management strategies that are tailored to differential symptom and pathogenic responses to VAD implantation.

Research design features and patient characteristics associated with the outcome of antidepressant clinical trials.

PubMed

Khan, Arif; Kolts, Russell L; Thase, Michael E; Krishnan, K Ranga Rama; Brown, Walter

2004-11-01

The authors examined which, if any, research design features and patient characteristics would significantly differ between successful and unsuccessful antidepressant trials. Clinical trial data were reviewed for nine antidepressants approved by the Food and Drug Administration between 1985 and 2000. From the antidepressant research programs on these medications, 52 clinical trials were included in the study. The authors evaluated trial design features, patient characteristics, and difference in response between placebo and antidepressant. Nine trial design features and patient characteristics were present in the research programs for all nine of the antidepressants. The severity of depressive symptoms before patient randomization, the dosing schedule (flexible versus fixed), the number of treatment arms, and the percentage of female patients were significantly associated with the difference in response to antidepressant and placebo. The duration of the antidepressant trial, number of patients per treatment arm, number of sites, and mean age of the patients were similar in successful trials (with a greater antidepressant-placebo difference) and less successful trials (with a smaller antidepressant-placebo difference). These findings may help in the design of future antidepressant trials.

Control-Relevant Modeling, Analysis, and Design for Scramjet-Powered Hypersonic Vehicles

NASA Technical Reports Server (NTRS)

Rodriguez, Armando A.; Dickeson, Jeffrey J.; Sridharan, Srikanth; Benavides, Jose; Soloway, Don; Kelkar, Atul; Vogel, Jerald M.

2009-01-01

Within this paper, control-relevant vehicle design concepts are examined using a widely used 3 DOF (plus flexibility) nonlinear model for the longitudinal dynamics of a generic carrot-shaped scramjet powered hypersonic vehicle. Trade studies associated with vehicle/engine parameters are examined. The impact of parameters on control-relevant static properties (e.g. level-flight trimmable region, trim controls, AOA, thrust margin) and dynamic properties (e.g. instability and right half plane zero associated with flight path angle) are examined. Specific parameters considered include: inlet height, diffuser area ratio, lower forebody compression ramp inclination angle, engine location, center of gravity, and mass. Vehicle optimizations is also examined. Both static and dynamic considerations are addressed. The gap-metric optimized vehicle is obtained to illustrate how this control-centric concept can be used to "reduce" scheduling requirements for the final control system. A classic inner-outer loop control architecture and methodology is used to shed light on how specific vehicle/engine design parameter selections impact control system design. In short, the work represents an important first step toward revealing fundamental tradeoffs and systematically treating control-relevant vehicle design.

Enhancing the Practicum Experience for Pre-service Chemistry Teachers Through Collaborative CoRe Design with Mentor Teachers

NASA Astrophysics Data System (ADS)

Hume, Anne; Berry, Amanda

2013-10-01

This paper reports findings from an ongoing study exploring how the Content Representation (CoRe) design can be used as a tool to help chemistry student teachers begin acquiring the professional knowledge required to become expert chemistry teachers. Phase 2 of the study, reported in this paper, investigated how collaboration with school-based mentors (associate teachers) on teaching practice (practicum) might impact on this process and student teachers' development of their pedagogical content knowledge (PCK). The collaboration involved identifying and discussing pedagogical issues related to a practicum-teaching topic using a student teacher's draft CoRe as a starting point and ongoing focus for the professional dialogue. Practicum offered an opportunity for aspects of student teachers' PCK, as embodied in their draft CoRes, to be explored and expanded upon in classroom programmes with the support and input of associate teachers. The findings were influenced by different contextual factors; however, the student teachers found their CoRes to be very useful frameworks for engaging in focussed professional dialogue with their teaching mentors. They valued the expertise, currency of knowledge and mentoring of their associates and reported positively about the contribution this support made to their PCK development via the CoRe design process and the transformation of the CoRe into classroom teaching.

Is ambient air pollution associated with onset of sudden infant death syndrome: a case-crossover study in the UK

PubMed Central

Ayres, Jon G; Mohammed, Nuredin I

2018-01-01

Objectives Air pollution has been associated with increased mortality and morbidity in several studies with indications that its effect could be more severe in children. This study examined the relationship between short-term variations in criteria air pollutants and occurrence of sudden infant death syndrome (SIDS). Design We used a case-crossover study design which is widely applied in air pollution studies and particularly useful for estimating the risk of a rare acute outcome associated with short-term exposure. Setting The study used data from the West Midlands region in the UK. Participants We obtained daily time series data on SIDS mortality (ICD-9: 798.0 or ICD-10: R95) for the period 1996–2006 with a total of 211 SIDS events. Primary outcome measures Daily counts of SIDS events. Results For an IQR increase in previous day pollutant concentration, the percentage increases (95% CI) in SIDS were 16 (6 to 27) for PM10, 1 (−7 to 10) for SO2, 5 (−4 to 14) for CO, −17 (−27 to –6) for O3, 16 (2 to 31) for NO2 and 2 (−3 to 8) for NO after controlling for average temperature and national holidays. PM10 and NO2 showed relatively consistent association which persisted across different lag structures and after adjusting for copollutants. Conclusions The results indicated ambient air pollutants, particularly PM10 and NO2, may show an association with increased SIDS mortality. Thus, future studies are recommended to understand possible mechanistic explanations on the role of air pollution on SIDS incidence and the ways in which we might reduce pollution exposure among infants. PMID:29654005

Childhood physical maltreatment, perceived social isolation, and internalizing symptoms: a longitudinal, three-wave, population-based study.

PubMed

Sheikh, Mashhood Ahmed

2018-04-01

A number of cross-sectional studies have consistently shown a correlation between childhood physical maltreatment, perceived social isolation and internalizing symptoms. Using a longitudinal, three-wave design, this study sought to assess the mediating role of perceived social isolation in adulthood in the association between childhood physical maltreatment and internalizing symptoms in adulthood. The study has a three-wave design. We used data collected from 1994 to 2008 within the framework of the Tromsø Study (N = 4530), a representative prospective cohort study of men and women. Perceived social isolation was measured at a mean age of 54.7 years, and internalizing symptoms were measured at a mean age of 61.7 years. The difference-in-coefficients method was used to assess the indirect effects and the proportion (%) of mediated effects. Childhood physical maltreatment was associated with an up to 68% [relative risk (RR) = 1.68, 95% confidence interval (CI): 1.33-2.13] higher risk of perceived social isolation in adulthood. Childhood physical maltreatment and perceived social isolation in adulthood were associated with greater levels of internalizing symptoms in adulthood (p < 0.01). A dose-response association was observed between childhood physical maltreatment and internalizing symptoms in adulthood (p < 0.001). Perceived social isolation in adulthood mediated up to 14.89% (p < 0.05) of the association between childhood physical maltreatment and internalizing symptoms in adulthood. The results of this study indicate the need to take perceived social isolation into account when considering the impact of childhood physical maltreatment on internalizing symptoms.

Factors Associated with Participation and Attrition in a Longitudinal Study of Bacterial Vaginosis in Australian Women Who Have Sex with Women

PubMed Central

Forcey, Dana S.; Walker, Sandra M.; Vodstrcil, Lenka A.; Fairley, Christopher K.; Bilardi, Jade E.; Law, Matthew; Hocking, Jane S.; Fethers, Katherine A.; Petersen, Susan; Bellhouse, Clare; Chen, Marcus Y.; Bradshaw, Catriona S.

2014-01-01

Objective A number of social and sexual risk factors for bacterial vaginosis (BV) have been described. It is important to understand whether these factors are associated with non-participation or attrition of participants from longitudinal studies in order to examine potential for recruitment or attrition bias. We describe factors associated with participation and attrition in a 24-month prospective cohort study, investigating incident BV among Australian women who have sex with women. Study Design and Setting Participants negative for prevalent BV were offered enrolment in a longitudinal cohort study. Participants self-collected vaginal samples and completed questionnaires 3-monthly to endpoint (BV-positive/BV-negative by 24 months). Factors associated with participation in the cohort study were examined by logistic regression and factors associated with attrition from the cohort were examined by Cox regression. Results The cross-sectional study recruited 457 women. 334 BV-negative women were eligible for the cohort and 298 (89%, 95%CI 85, 92) enrolled. Lower educational levels (aOR 2.72, 95%CI 1.09, 6.83), smoking (aOR 2.44, 95%CI 1.13, 5.27), past BV symptoms (aOR 3.42, 95%CI 1.16, 10.10) and prior genital warts (aOR 2.71, 95%CI 1.14, 6.46) were associated with non-participation; a partner co-enrolling increased participation (aOR 3.73, 95%CI 1.43, 9.70). 248 participants (83%, 95%CI 78, 87) were retained to study endpoint (BV-negative at 24 months or BV-positive at any stage). Attrition was associated being <30 yrs (aHR 2.15, 95%CI 1.13, 4.10) and a male partner at enrolment (aHR 6.12, 95%CI 1.99, 18.82). Conclusion We achieved high participation and retention levels in a prospective cohort study and report factors influencing participation and retention of participants over a 24-month study period, which will assist in the design and implementation of future cohort studies in sexual health and disease. PMID:25412421

Association between the 2008–09 Seasonal Influenza Vaccine and Pandemic H1N1 Illness during Spring–Summer 2009: Four Observational Studies from Canada

PubMed Central

Skowronski, Danuta M.; De Serres, Gaston; Crowcroft, Natasha S.; Janjua, Naveed Z.; Boulianne, Nicole; Hottes, Travis S.; Rosella, Laura C.; Dickinson, James A.; Gilca, Rodica; Sethi, Pam; Ouhoummane, Najwa; Willison, Donald J.; Rouleau, Isabelle; Petric, Martin; Fonseca, Kevin; Drews, Steven J.; Rebbapragada, Anuradha; Charest, Hugues; Hamelin, Marie-Ève; Boivin, Guy; Gardy, Jennifer L.; Li, Yan; Kwindt, Trijntje L.; Patrick, David M.; Brunham, Robert C.

2010-01-01

Background In late spring 2009, concern was raised in Canada that prior vaccination with the 2008–09 trivalent inactivated influenza vaccine (TIV) was associated with increased risk of pandemic influenza A (H1N1) (pH1N1) illness. Several epidemiologic investigations were conducted through the summer to assess this putative association. Methods and Findings Studies included: (1) test-negative case-control design based on Canada's sentinel vaccine effectiveness monitoring system in British Columbia, Alberta, Ontario, and Quebec; (2) conventional case-control design using population controls in Quebec; (3) test-negative case-control design in Ontario; and (4) prospective household transmission (cohort) study in Quebec. Logistic regression was used to estimate odds ratios for TIV effect on community- or hospital-based laboratory-confirmed seasonal or pH1N1 influenza cases compared to controls with restriction, stratification, and adjustment for covariates including combinations of age, sex, comorbidity, timeliness of medical visit, prior physician visits, and/or health care worker (HCW) status. For the prospective study risk ratios were computed. Based on the sentinel study of 672 cases and 857 controls, 2008–09 TIV was associated with statistically significant protection against seasonal influenza (odds ratio 0.44, 95% CI 0.33–0.59). In contrast, estimates from the sentinel and three other observational studies, involving a total of 1,226 laboratory-confirmed pH1N1 cases and 1,505 controls, indicated that prior receipt of 2008–09 TIV was associated with increased risk of medically attended pH1N1 illness during the spring–summer 2009, with estimated risk or odds ratios ranging from 1.4 to 2.5. Risk of pH1N1 hospitalization was not further increased among vaccinated people when comparing hospitalized to community cases. Conclusions Prior receipt of 2008–09 TIV was associated with increased risk of medically attended pH1N1 illness during the spring–summer 2009 in Canada. The occurrence of bias (selection, information) or confounding cannot be ruled out. Further experimental and epidemiological assessment is warranted. Possible biological mechanisms and immunoepidemiologic implications are considered. Please see later in the article for the Editors' Summary PMID:20386731

Guidelines for Design and Sampling for Cyanobacterial Toxin and Taste-and-Odor Studies in Lakes and Reservoirs

USGS Publications Warehouse

Graham, Jennifer L.; Loftin, Keith A.; Ziegler, Andrew C.; Meyer, Michael T.

2008-01-01

Cyanobacteria and associated toxins and taste-and-odor compounds are of increasing environmental concern. However, consistent guidelines for the development of studies assessing cyanobacterial toxins and taste-and-odor compounds presently are not available. This report provides guidance for the development of scientific studies of cyanobacteria and associated by-products in lakes and reservoirs. Topics include: background information on cyanobacteria, toxins, and taste-and-odor compounds; spatial and temporal considerations that are unique to the cyanobacteria in lakes and reservoirs; common study types, objectives, and approaches for studies of cyanobacteria and associated toxins and taste-and-odor compounds; general guidelines for collecting samples; and information on sample handling, preparation, processing, and shipping.

Perception of Safety and Liking Associated to the Colour Intervention of Bike Lanes: Contribution from the Behavioural Sciences to Urban Design and Wellbeing.

PubMed

Vera-Villarroel, Pablo; Contreras, Daniela; Lillo, Sebastián; Beyle, Christian; Segovia, Ariel; Rojo, Natalia; Moreno, Sandra; Oyarzo, Francisco

2016-01-01

The perception of colour and its subjective effects are key issues to designing safe and enjoyable bike lanes. This paper addresses the relationship between the colours of bike lane interventions-in particular pavement painting and intersection design-and the subjective evaluation of liking, visual saliency, and perceived safety related to such an intervention. Utilising images of three real bike lane intersections modified by software to change their colour (five in total), this study recruited 538 participants to assess their perception of all fifteen colour-design combinations. A multivariate analysis of covariance (MANCOVA) with the Bonferroni post hoc test was performed to assess the effect of the main conditions (colour and design) on the dependent variables (liking towards the intervention, level of visual saliency of the intersection, and perceived safety of the bike lane). The results showed that the colour red was more positively associated to the outcome variables, followed by yellow and blue. Additionally, it was observed that the effect of colour widely outweighs the effect of design, suggesting that the right choice and use of colour would increase the effectiveness on bike-lanes pavement interventions. Limitations and future directions are discussed.