A randomised trial and economic evaluation of the effect of response mode on response rate, response bias, and item non-response in a survey of doctors

PubMed Central

2011-01-01

Background Surveys of doctors are an important data collection method in health services research. Ways to improve response rates, minimise survey response bias and item non-response, within a given budget, have not previously been addressed in the same study. The aim of this paper is to compare the effects and costs of three different modes of survey administration in a national survey of doctors. Methods A stratified random sample of 4.9% (2,702/54,160) of doctors undertaking clinical practice was drawn from a national directory of all doctors in Australia. Stratification was by four doctor types: general practitioners, specialists, specialists-in-training, and hospital non-specialists, and by six rural/remote categories. A three-arm parallel trial design with equal randomisation across arms was used. Doctors were randomly allocated to: online questionnaire (902); simultaneous mixed mode (a paper questionnaire and login details sent together) (900); or, sequential mixed mode (online followed by a paper questionnaire with the reminder) (900). Analysis was by intention to treat, as within each primary mode, doctors could choose either paper or online. Primary outcome measures were response rate, survey response bias, item non-response, and cost. Results The online mode had a response rate 12.95%, followed by the simultaneous mixed mode with 19.7%, and the sequential mixed mode with 20.7%. After adjusting for observed differences between the groups, the online mode had a 7 percentage point lower response rate compared to the simultaneous mixed mode, and a 7.7 percentage point lower response rate compared to sequential mixed mode. The difference in response rate between the sequential and simultaneous modes was not statistically significant. Both mixed modes showed evidence of response bias, whilst the characteristics of online respondents were similar to the population. However, the online mode had a higher rate of item non-response compared to both mixed modes. The total cost of the online survey was 38% lower than simultaneous mixed mode and 22% lower than sequential mixed mode. The cost of the sequential mixed mode was 14% lower than simultaneous mixed mode. Compared to the online mode, the sequential mixed mode was the most cost-effective, although exhibiting some evidence of response bias. Conclusions Decisions on which survey mode to use depend on response rates, response bias, item non-response and costs. The sequential mixed mode appears to be the most cost-effective mode of survey administration for surveys of the population of doctors, if one is prepared to accept a degree of response bias. Online surveys are not yet suitable to be used exclusively for surveys of the doctor population. PMID:21888678

[Not Available].

PubMed

Paturzo, Marco; Colaceci, Sofia; Clari, Marco; Mottola, Antonella; Alvaro, Rosaria; Vellone, Ercole

2016-01-01

. Mixed methods designs: an innovative methodological approach for nursing research. The mixed method research designs (MM) combine qualitative and quantitative approaches in the research process, in a single study or series of studies. Their use can provide a wider understanding of multifaceted phenomena. This article presents a general overview of the structure and design of MM to spread this approach in the Italian nursing research community. The MM designs most commonly used in the nursing field are the convergent parallel design, the sequential explanatory design, the exploratory sequential design and the embedded design. For each method a research example is presented. The use of MM can be an added value to improve clinical practices as, through the integration of qualitative and quantitative methods, researchers can better assess complex phenomena typical of nursing.

Parents' School Satisfaction and Academic Socialization Predict Adolescents' Autonomous Motivation: A Mixed-Method Study of Low-Income Ethnic Minority Families

ERIC Educational Resources Information Center

Suizzo, Marie-Anne; Jackson, Karen Moran; Pahlke, Erin; McClain, Shannon; Marroquin, Yesenia; Blondeau, Lauren A.; Hong, KyongJoo

2016-01-01

In this mixed-methods study, we used an explanatory sequential design to investigate the processes through which parental involvement influences adolescents' achievement motivation. One hundred twenty low-income urban parents and their sixth-grade adolescents completed questionnaires, and a subsample of 11 mothers and 11 adolescents were…

Attitudes toward Using Social Networking Sites in Educational Settings with Underperforming Latino Youth: A Mixed Methods Study

ERIC Educational Resources Information Center

Howard, Keith E.; Curwen, Margie Sauceda; Howard, Nicol R.; Colón-Muñiz, Anaida

2015-01-01

The researchers examined the online social networking attitudes of underperforming Latino high school students in an alternative education program that uses technology as the prime venue for learning. A sequential explanatory mixed methods study was used to cross-check multiple sources of data explaining students' levels of comfort with utilizing…

Faculty and Administrator Perspectives of Merit Pay Compensation Systems in Private Higher Education: A Mixed Methods Analysis

ERIC Educational Resources Information Center

Power, Anne L.

2013-01-01

The purpose of this explanatory sequential mixed methods study is to explore faculty and administrator perspectives of faculty merit pay compensation systems in private, higher education institutions. The study focuses on 10 small, private, four-year institutions which are religiously affiliated. All institutions are located in Nebraska, Iowa, and…

Educating Linguistically Diverse Students: A Mixed Methods Study of Elementary Teachers' Coursework, Attitudes, and Practice

ERIC Educational Resources Information Center

Greenfield, Renée A.

2016-01-01

This study followed a mixed-methods sequential explanatory design. Phase I involved the collection of quantitative data to examine inservice teachers' (N = 69) attitudes about language and linguistic diversity as well as their teacher education coursework. All participants were graduates from the same teacher education program. Phase II included…

Exploring the Relationship between Fidelity of Implementation and Academic Achievement in a Third-Grade Gifted Curriculum: A Mixed-Methods Study

ERIC Educational Resources Information Center

Azano, Amy; Missett, Tracy C.; Callahan, Carolyn M.; Oh, Sarah; Brunner, Marguerite; Foster, Lisa H.; Moon, Tonya R.

2011-01-01

This study used sequential mixed-methods analyses to investigate the effectiveness of a research-based language arts curriculum for gifted third graders. Using analytic induction, researchers found that teachers' beliefs and expectations (time, sense of autonomy, expectations for students, professional expertise) influenced the degree to which…

Teachers' Adoptation Level of Student Centered Education Approach

ERIC Educational Resources Information Center

Arseven, Zeynep; Sahin, Seyma; Kiliç, Abdurrahman

2016-01-01

The aim of this study is to identify how far the student centered education approach is applied in the primary, middle and high schools in Düzce. Explanatory design which is one type of mixed research methods and "sequential mixed methods sampling" were used in the study. 685 teachers constitute the research sample of the quantitative…

A Mixed Methods Study of the Relationship between Student Perceptions of Teacher-Student Interactions and Motivation in Middle Level Science

ERIC Educational Resources Information Center

Smart, Julie B.

2014-01-01

This mixed-methods study examined the relationship between middle level science students' perceptions of teacher-student interactions and students' science motivation, particulary their efficacy, value, and goal orientation for learning science. In this sequential explanatory design, quantitative and qualitative data were collected in two phases,…

Examining the Literacy Histories of Doctoral Students in an Educational Studies Program through Surveys and Interviews: A Mixed Methods Study

ERIC Educational Resources Information Center

Adams-Budde, Melissa; Howard, Christy; Jolliff, Grant; Myers, Joy

2014-01-01

The purpose of this mixed methods sequential explanatory study was to explain the relationship between literacy experiences over time and the literacy identities of the doctoral students in a teacher education and higher education program. The quantitative phase, surveying 36 participants, revealed a positive correlation between participant's…

The Motivating Language of Principals: A Sequential Transformative Strategy

ERIC Educational Resources Information Center

Holmes, William Tobias

2012-01-01

This study implemented a Sequential Transformative Mixed Methods design with teachers (as recipients) and principals (to give voice) in the examination of principal talk in two different school accountability contexts (Continuously Improving and Continuously Zigzag) using the conceptual framework of Motivating Language Theory. In phase one,…

Thai Perspectives on the Internationalization of Higher Education in Thailand: A Mixed Methods Analysis and Three Mini-Case Studies

ERIC Educational Resources Information Center

McBride, Karen Anne

2012-01-01

This study is a sequential mixed methods study that also includes three mini-case studies for the purpose of portraying contemporary Thai views on the internationalization of higher education in Thailand and reflections on its status as an international education hub in the Southeast Asian region. An inductive analysis technique is used whereby…

From Ethnography to Items: A Mixed Methods Approach to Developing a Survey to Examine Graduate Engineering Student Retention

ERIC Educational Resources Information Center

Crede, Erin; Borrego, Maura

2013-01-01

As part of a sequential exploratory mixed methods study, 9 months of ethnographically guided observations and interviews were used to develop a survey examining graduate engineering student retention. Findings from the ethnographic fieldwork yielded several themes, including international diversity, research group organization and climate,…

How Do High School Students Solve Probability Problems? A Mixed Methods Study on Probabilistic Reasoning

ERIC Educational Resources Information Center

Heyvaert, Mieke; Deleye, Maarten; Saenen, Lore; Van Dooren, Wim; Onghena, Patrick

2018-01-01

When studying a complex research phenomenon, a mixed methods design allows to answer a broader set of research questions and to tap into different aspects of this phenomenon, compared to a monomethod design. This paper reports on how a sequential equal status design (QUAN ? QUAL) was used to examine students' reasoning processes when solving…

Supporting Girls' and Boys' Engagement in Math and Science Learning: A Mixed Methods Study

ERIC Educational Resources Information Center

Fredricks, Jennifer A.; Hofkens, Tara; Wang, Ming-Te; Mortenson, Elizabeth; Scott, Paul

2018-01-01

This study uses a mixed method sequential exploratory design to examine motivational and contextual influences on boys' and girls' engagement in math and science, paying particular attention to similarities and differences in the patterns by gender. First, interviews were conducted with 38 middle and high school students who varied in their level…

College in Mind: A Mixed-Methods Study of How Emerging Adults with Psychiatric Disabilities Prepare for and Transition to and through Higher Education

ERIC Educational Resources Information Center

Murray, Laura Carolyn

2017-01-01

This dissertation study employs an exploratory sequential mixed methods design to investigate how emerging adults with psychiatric disabilities plan for and transition to and through college. Special attention is paid to how disclosure of disability status in educational contexts can influence both educational and recovery outcomes. Though more…

An Explanatory Sequential Mixed-Method Investigation of Athletic Training Students' Perceptions of Preceptor Mentorship and Board of Certification Exam Success

ERIC Educational Resources Information Center

Fordham, Sabrina R.

2015-01-01

The purpose of this study was to investigate the relationship between preceptor mentorship to athletic training students and first-attempt success on the Board of Certification (BOC) exam. Adult learning theory provides the theoretical framework. The study followed a mixed-method approach, using a focus-group discussion to gain a qualitative…

Teacher Education Preparation and Implementation for Multicultural and Diverse School Environments in the 21st Century: A Mixed Methods Study

ERIC Educational Resources Information Center

Cole, Patricia Ann

2013-01-01

This sequential explanatory mixed methods study investigated 24 college and university syllabi for content consisting of multicultural education that used the framework for multicultural education devised by James A. Banks (2006). This framework was used to analyze data collected using descriptive statistics for quantitative phase one. The four…

The Impact of Student Teaching Experience on Pre-Service Teachers' Readiness for Technology Integration: A Mixed Methods Study with Growth Curve Modeling

ERIC Educational Resources Information Center

Sun, Yan; Strobel, Johannes; Newby, Timothy J.

2017-01-01

Adopting a two-phase explanatory sequential mixed methods research design, the current study examined the impact of student teaching experiences on pre-service teachers' readiness for technology integration. In phase-1 of quantitative investigation, 2-level growth curve models were fitted using online repeated measures survey data collected from…

Junior and Senior High School EFL Teachers' Use of Formative Assessment: A Mixed-Methods Study

ERIC Educational Resources Information Center

Saito, Hidetoshi; Inoi, Shin'ichi

2017-01-01

Despite the rising interest in the practice of formative assessment (FA) in language classrooms, research has rarely examined the factors that contribute to differential use of FA. The present study adopts an explanatory sequential mixed-method design to examine differences in FA use among Japanese junior and senior high school EFL (English as a…

Exploring Student Use of Social Networking Services (SNS) Surrounding Moral Development, Gender, Campus Crime, Safety, and the Clery Act: A Mixed Methods Study

ERIC Educational Resources Information Center

Baum, Haley

2017-01-01

The purpose of this explanatory sequential mixed methods study was to explore college students' use of social networking services (SNS); examining how and why they communicate about campus safety information. This study took place at Stockton University, a regional state institution in NJ. Undergraduate students took part in an online quantitative…

Combining qualitative and quantitative research within mixed method research designs: a methodological review.

PubMed

Östlund, Ulrika; Kidd, Lisa; Wengström, Yvonne; Rowa-Dewar, Neneh

2011-03-01

It has been argued that mixed methods research can be useful in nursing and health science because of the complexity of the phenomena studied. However, the integration of qualitative and quantitative approaches continues to be one of much debate and there is a need for a rigorous framework for designing and interpreting mixed methods research. This paper explores the analytical approaches (i.e. parallel, concurrent or sequential) used in mixed methods studies within healthcare and exemplifies the use of triangulation as a methodological metaphor for drawing inferences from qualitative and quantitative findings originating from such analyses. This review of the literature used systematic principles in searching CINAHL, Medline and PsycINFO for healthcare research studies which employed a mixed methods approach and were published in the English language between January 1999 and September 2009. In total, 168 studies were included in the results. Most studies originated in the United States of America (USA), the United Kingdom (UK) and Canada. The analytic approach most widely used was parallel data analysis. A number of studies used sequential data analysis; far fewer studies employed concurrent data analysis. Very few of these studies clearly articulated the purpose for using a mixed methods design. The use of the methodological metaphor of triangulation on convergent, complementary, and divergent results from mixed methods studies is exemplified and an example of developing theory from such data is provided. A trend for conducting parallel data analysis on quantitative and qualitative data in mixed methods healthcare research has been identified in the studies included in this review. Using triangulation as a methodological metaphor can facilitate the integration of qualitative and quantitative findings, help researchers to clarify their theoretical propositions and the basis of their results. This can offer a better understanding of the links between theory and empirical findings, challenge theoretical assumptions and develop new theory. Copyright © 2010 Elsevier Ltd. All rights reserved.

A Mixed Methods Examination of the Influence of Dimensions of Support on Training Transfer

ERIC Educational Resources Information Center

Schindler, Laura A.; Burkholder, Gary J.

2016-01-01

The purpose of this mixed methods sequential explanatory study was to explore how specific dimensions of supervisor support (mentoring, coaching, social support, and task support) influence the transfer of learned knowledge and skills to the job. Quantitative data were collected from employees (N = 48) who develop curriculum at an educational…

Motivational Characteristics of Prospective Teachers with Different Levels of Commitment to Teaching: A Mixed-Methods Investigation

ERIC Educational Resources Information Center

Thomson, Margareta Maria

2013-01-01

This study explored the U.S. prospective teachers' motivations for teaching, teaching goal development, and views of their commitment to teaching. A sequential explanatory mixed-methods design was employed. Participants (N = 61) completed a survey in which they rated the importance of various factors in their teaching career choice. Furthermore,…

Academic Dishonesty: A Mixed-Method Study of Rational Choice among Students at the College of Basic Education in Kuwait

ERIC Educational Resources Information Center

Alsuwaileh, Bader Ghannam; Russ-Eft, Darlene F.; Alshurai, Saad R.

2016-01-01

The research herein used a sequential mixed methods design to investigate why academic dishonesty is widespread among the students at the College of Basic Education in Kuwait. Qualitative interviews were conducted to generate research hypotheses. Then, using questionnaire survey, the research hypotheses were quantitatively tested. The findings…

Bridging the qualitative-quantitative divide: Experiences from conducting a mixed methods evaluation in the RUCAS programme.

PubMed

Makrakis, Vassilios; Kostoulas-Makrakis, Nelly

2016-02-01

Quantitative and qualitative approaches to planning and evaluation in education for sustainable development have often been treated by practitioners from a single research paradigm. This paper discusses the utility of mixed method evaluation designs which integrate qualitative and quantitative data through a sequential transformative process. Sequential mixed method data collection strategies involve collecting data in an iterative process whereby data collected in one phase contribute to data collected in the next. This is done through examples from a programme addressing the 'Reorientation of University Curricula to Address Sustainability (RUCAS): A European Commission Tempus-funded Programme'. It is argued that the two approaches are complementary and that there are significant gains from combining both. Using methods from both research paradigms does not, however, mean that the inherent differences among epistemologies and methodologies should be neglected. Based on this experience, it is recommended that using a sequential transformative mixed method evaluation can produce more robust results than could be accomplished using a single approach in programme planning and evaluation focussed on education for sustainable development. Copyright © 2015 Elsevier Ltd. All rights reserved.

A Mixed Methods Study on Teachers' Perceptions of Readiness of Higher Education Institutions to the Implementation of the K-12 Curriculum

ERIC Educational Resources Information Center

Acosta, Imee C.; Acosta, Alexander S.

2017-01-01

The Philippine Educational System is undergoing a major overhaul that shifts from a 10-year education to 12 years known as Enhanced Basic Education Curriculum or K-12. The purpose of this mixed-methods sequential explanatory study was to identify factors that determine readiness of select higher education institutions to the full implementation of…

Customer-Focused Business Practice Adoption: A Comparison of Private and Public Sector Implementations

DTIC Science & Technology

2004-03-01

Narratives Phenomenologies Ethnographies Grounded Theory Case Studies Mixed Methods Sequential Concurrent Transformative Creswell... ethnographies , grounded theory studies and case studies (Creswell, 2003:18). The methods used in qualitative study provide the framework for...Definition Grounded theory provides a structured

Exploring the Impact of Online Peer-Editing Using Google Docs on EFL Learners' Academic Writing Skills: A Mixed Methods Study

ERIC Educational Resources Information Center

Ebadi, Saman; Rahimi, Masoud

2017-01-01

This article reports the results of a sequential explanatory mixed-methods approach to explore the impact of online peer-editing using Google Docs and peer-editing in a face-to-face classroom on EFL learners' academic writing skills. As the study adopted a quasi-experimental design, two intact classes, each with ten EFL learners, attending an…

Health risk behaviours amongst school adolescents: protocol for a mixed methods study.

PubMed

El Achhab, Youness; El Ammari, Abdelghaffar; El Kazdouh, Hicham; Najdi, Adil; Berraho, Mohamed; Tachfouti, Nabil; Lamri, Driss; El Fakir, Samira; Nejjari, Chakib

2016-11-29

Determining risky behaviours of adolescents provides valuable information for designing appropriate intervention programmes for advancing adolescent's health. However, these behaviours are not fully addressed by researchers in a comprehensive approach. We report the protocol of a mixed methods study designed to investigate the health risk behaviours of Moroccan adolescents with the goal of identifying suitable strategies to address their health concerns. We used a sequential two-phase explanatory mixed method study design. The approach begins with the collection of quantitative data, followed by the collection of qualitative data to explain and enrich the quantitative findings. In the first phase, the global school-based student health survey (GSHS) was administered to 800 students who were between 14 and 19 years of age. The second phase engaged adolescents, parents and teachers in focus groups and assessed education documents to explore the level of coverage of health education in the programme learnt in the middle school. To obtain opinions about strategies to reduce Moroccan adolescents' health risk behaviours, a nominal group technique will be used. The findings of this mixed methods sequential explanatory study provide insights into the risk behaviours that need to be considered if intervention programmes and preventive strategies are to be designed to promote adolescent's health in the Moroccan school.

A sampling and classification item selection approach with content balancing.

PubMed

Chen, Pei-Hua

2015-03-01

Existing automated test assembly methods typically employ constrained combinatorial optimization. Constructing forms sequentially based on an optimization approach usually results in unparallel forms and requires heuristic modifications. Methods based on a random search approach have the major advantage of producing parallel forms sequentially without further adjustment. This study incorporated a flexible content-balancing element into the statistical perspective item selection method of the cell-only method (Chen et al. in Educational and Psychological Measurement, 72(6), 933-953, 2012). The new method was compared with a sequential interitem distance weighted deviation model (IID WDM) (Swanson & Stocking in Applied Psychological Measurement, 17(2), 151-166, 1993), a simultaneous IID WDM, and a big-shadow-test mixed integer programming (BST MIP) method to construct multiple parallel forms based on matching a reference form item-by-item. The results showed that the cell-only method with content balancing and the sequential and simultaneous versions of IID WDM yielded results comparable to those obtained using the BST MIP method. The cell-only method with content balancing is computationally less intensive than the sequential and simultaneous versions of IID WDM.

A randomised trial and economic evaluation of the effect of response mode on response rate, response bias, and item non-response in a survey of doctors.

PubMed

Scott, Anthony; Jeon, Sung-Hee; Joyce, Catherine M; Humphreys, John S; Kalb, Guyonne; Witt, Julia; Leahy, Anne

2011-09-05

Surveys of doctors are an important data collection method in health services research. Ways to improve response rates, minimise survey response bias and item non-response, within a given budget, have not previously been addressed in the same study. The aim of this paper is to compare the effects and costs of three different modes of survey administration in a national survey of doctors. A stratified random sample of 4.9% (2,702/54,160) of doctors undertaking clinical practice was drawn from a national directory of all doctors in Australia. Stratification was by four doctor types: general practitioners, specialists, specialists-in-training, and hospital non-specialists, and by six rural/remote categories. A three-arm parallel trial design with equal randomisation across arms was used. Doctors were randomly allocated to: online questionnaire (902); simultaneous mixed mode (a paper questionnaire and login details sent together) (900); or, sequential mixed mode (online followed by a paper questionnaire with the reminder) (900). Analysis was by intention to treat, as within each primary mode, doctors could choose either paper or online. Primary outcome measures were response rate, survey response bias, item non-response, and cost. The online mode had a response rate 12.95%, followed by the simultaneous mixed mode with 19.7%, and the sequential mixed mode with 20.7%. After adjusting for observed differences between the groups, the online mode had a 7 percentage point lower response rate compared to the simultaneous mixed mode, and a 7.7 percentage point lower response rate compared to sequential mixed mode. The difference in response rate between the sequential and simultaneous modes was not statistically significant. Both mixed modes showed evidence of response bias, whilst the characteristics of online respondents were similar to the population. However, the online mode had a higher rate of item non-response compared to both mixed modes. The total cost of the online survey was 38% lower than simultaneous mixed mode and 22% lower than sequential mixed mode. The cost of the sequential mixed mode was 14% lower than simultaneous mixed mode. Compared to the online mode, the sequential mixed mode was the most cost-effective, although exhibiting some evidence of response bias. Decisions on which survey mode to use depend on response rates, response bias, item non-response and costs. The sequential mixed mode appears to be the most cost-effective mode of survey administration for surveys of the population of doctors, if one is prepared to accept a degree of response bias. Online surveys are not yet suitable to be used exclusively for surveys of the doctor population.

Guidance for using mixed methods design in nursing practice research.

PubMed

Chiang-Hanisko, Lenny; Newman, David; Dyess, Susan; Piyakong, Duangporn; Liehr, Patricia

2016-08-01

The mixed methods approach purposefully combines both quantitative and qualitative techniques, enabling a multi-faceted understanding of nursing phenomena. The purpose of this article is to introduce three mixed methods designs (parallel; sequential; conversion) and highlight interpretive processes that occur with the synthesis of qualitative and quantitative findings. Real world examples of research studies conducted by the authors will demonstrate the processes leading to the merger of data. The examples include: research questions; data collection procedures and analysis with a focus on synthesizing findings. Based on experience with mixed methods studied, the authors introduce two synthesis patterns (complementary; contrasting), considering application for practice and implications for research. Copyright © 2015 Elsevier Inc. All rights reserved.

Assistant Principals and Reform: A Socialization Paradox?

ERIC Educational Resources Information Center

Best, Marguerita L.

2013-01-01

Framed in the critical race theory of structuration (CRTS), this sequential explanatory mixed methods study seeks to identify the socialization practices by examining the realities of practices of assistant principals and the ways in which they impact the disciplinary actions of assistant principals at middle and high schools. The mixed methods…

How and Why Digital Generation Teachers Use Technology in the Classroom: An Explanatory Sequential Mixed Methods Study

ERIC Educational Resources Information Center

Li, Lan; Worch, Eric; Zhou, YuChun; Aguiton, Rhonda

2015-01-01

While teachers' conservative attitude toward technology has been identified as a barrier to effective technology integration in classrooms, it is often optimistically assumed that this issue will resolve when the digital generation enters the teaching profession (Morris, 2012). Using a mixed methodology approach, this study aimed to examine the…

Integrating Quantitative and Qualitative Results in Health Science Mixed Methods Research Through Joint Displays

PubMed Central

Guetterman, Timothy C.; Fetters, Michael D.; Creswell, John W.

2015-01-01

PURPOSE Mixed methods research is becoming an important methodology to investigate complex health-related topics, yet the meaningful integration of qualitative and quantitative data remains elusive and needs further development. A promising innovation to facilitate integration is the use of visual joint displays that bring data together visually to draw out new insights. The purpose of this study was to identify exemplar joint displays by analyzing the various types of joint displays being used in published articles. METHODS We searched for empirical articles that included joint displays in 3 journals that publish state-of-the-art mixed methods research. We analyzed each of 19 identified joint displays to extract the type of display, mixed methods design, purpose, rationale, qualitative and quantitative data sources, integration approaches, and analytic strategies. Our analysis focused on what each display communicated and its representation of mixed methods analysis. RESULTS The most prevalent types of joint displays were statistics-by-themes and side-by-side comparisons. Innovative joint displays connected findings to theoretical frameworks or recommendations. Researchers used joint displays for convergent, explanatory sequential, exploratory sequential, and intervention designs. We identified exemplars for each of these designs by analyzing the inferences gained through using the joint display. Exemplars represented mixed methods integration, presented integrated results, and yielded new insights. CONCLUSIONS Joint displays appear to provide a structure to discuss the integrated analysis and assist both researchers and readers in understanding how mixed methods provides new insights. We encourage researchers to use joint displays to integrate and represent mixed methods analysis and discuss their value. PMID:26553895

Sex-Role Egalitarian Attitudes and Gender Role Socialization Experiences of African American Men and Women: A Mixed Methods Paradigm

ERIC Educational Resources Information Center

Heard, Courtney Christian Charisse

2013-01-01

The purpose of this study was to assess the sex-role egalitarian attitudes and gender role socialization experiences of African American men and women. A sequential mixed-methods design was employed to research this phenomenon. The Sex-Role Egalitarianism Scale-Short Form BB (SRES-BB) was utilized to assess sex-role egalitarian attitudes (King…

Motivating Teachers towards Expertise Development: A Mixed-Methods Study of the Relationships between School Culture, Internal Factors, and State of Flow

ERIC Educational Resources Information Center

Mayeaux, Amanda Shuford

2013-01-01

The purpose of this sequential mixed-methods research was to discover the impact school culture, internal factors, and the state of flow has upon motivating a teacher to develop teaching expertise. This research was designed to find answers concerning why and how individual teachers can nurture their existing internal factors to increase their…

Integrating Quantitative and Qualitative Results in Health Science Mixed Methods Research Through Joint Displays.

PubMed

Guetterman, Timothy C; Fetters, Michael D; Creswell, John W

2015-11-01

Mixed methods research is becoming an important methodology to investigate complex health-related topics, yet the meaningful integration of qualitative and quantitative data remains elusive and needs further development. A promising innovation to facilitate integration is the use of visual joint displays that bring data together visually to draw out new insights. The purpose of this study was to identify exemplar joint displays by analyzing the various types of joint displays being used in published articles. We searched for empirical articles that included joint displays in 3 journals that publish state-of-the-art mixed methods research. We analyzed each of 19 identified joint displays to extract the type of display, mixed methods design, purpose, rationale, qualitative and quantitative data sources, integration approaches, and analytic strategies. Our analysis focused on what each display communicated and its representation of mixed methods analysis. The most prevalent types of joint displays were statistics-by-themes and side-by-side comparisons. Innovative joint displays connected findings to theoretical frameworks or recommendations. Researchers used joint displays for convergent, explanatory sequential, exploratory sequential, and intervention designs. We identified exemplars for each of these designs by analyzing the inferences gained through using the joint display. Exemplars represented mixed methods integration, presented integrated results, and yielded new insights. Joint displays appear to provide a structure to discuss the integrated analysis and assist both researchers and readers in understanding how mixed methods provides new insights. We encourage researchers to use joint displays to integrate and represent mixed methods analysis and discuss their value. © 2015 Annals of Family Medicine, Inc.

A Method To Determine the Kinetics of Solute Mixing in Liquid/Liquid Formulation Dual-Chamber Syringes.

PubMed

Werk, Tobias; Mahler, Hanns-Christian; Ludwig, Imke Sonja; Luemkemann, Joerg; Huwyler, Joerg; Hafner, Mathias

Dual-chamber syringes were originally designed to separate a solid substance and its diluent. However, they can also be used to separate liquid formulations of two individual drug products, which cannot be co-formulated due to technical or regulatory issues. A liquid/liquid dual-chamber syringe can be designed to achieve homogenization and mixing of both solutions prior to administration, or it can be used to sequentially inject both solutions. While sequential injection can be easily achieved by a dual-chamber syringe with a bypass located at the needle end of the syringe barrel, mixing of the two fluids may provide more challenges. Within this study, the mixing behavior of surrogate solutions in different dual-chamber syringes is assessed. Furthermore, the influence of parameters such as injection angle, injection speed, agitation, and sample viscosity were studied. It was noted that mixing was poor for the commercial dual-chamber syringes (with a bypass designed as a longitudinal ridge) when the two liquids significantly differ in their physical properties (viscosity, density). However, an optimized dual-chamber syringe design with multiple bypass channels resulted in improved mixing of liquids. Dual-chamber syringes were originally designed to separate a solid substance and its diluent. However, they can also be used to separate liquid formulations of two individual drug products. A liquid/liquid dual-chamber syringe can be designed to achieve homogenization and mixing of both solutions prior to administration, or it can be used to sequentially inject both solutions. While sequential injection can be easily achieved by a dual-chamber syringe with a bypass located at the needle end of the syringe barrel, mixing of the two fluids may provide more challenges. Within this study, the mixing behavior of surrogate solutions in different dual-chamber syringes is assessed. Furthermore, the influence of parameters such as injection angle, injection speed, agitation, and sample viscosity were studied. It was noted that mixing was poor for the commercially available dual-chamber syringes when the two liquids significantly differ in viscosity and density. However, an optimized dual-chamber syringe design resulted in improved mixing of liquids. © PDA, Inc. 2017.

Focusing on What Counts: Using Exploratory Focus Groups to Enhance the Development of an Electronic Survey in a Mixed-Methods Research Design

ERIC Educational Resources Information Center

Galliott, Natal'ya; Graham, Linda J.

2016-01-01

This paper illustrates the use of exploratory focus groups to inform the development of a survey instrument in a sequential phase mixed-methods study investigating differences in secondary students' career choice capability. Five focus groups were conducted with 23 Year 10 students in the state of New South Wales, Australia. Analysis of the focus…

Comparison of solution-mixed and sequentially processed P3HT: F4TCNQ films: effect of doping-induced aggregation on film morphology

DOE PAGES

Jacobs, Ian E.; Aasen, Erik W.; Oliveira, Julia L.; ...

2016-03-23

Doping polymeric semiconductors often drastically reduces the solubility of the polymer, leading to difficulties in processing doped films. Here, we compare optical, electrical, and morphological properties of P3HT films doped with F4TCNQ, both from mixed solutions and using sequential solution processing with orthogonal solvents. We demonstrate that sequential doping occurs rapidly (<1 s), and that the film doping level can be precisely controlled by varying the concentration of the doping solution. Furthermore, the choice of sequential doping solvent controls whether dopant anions are included or excluded from polymer crystallites. Atomic force microscopy (AFM) reveals that sequential doping produces significantly moremore » uniform films on the nanoscale than the mixed-solution method. In addition, we show that mixed-solution doping induces the formation of aggregates even at low doping levels, resulting in drastic changes to film morphology. Sequentially coated films show 3–15 times higher conductivities at a given doping level than solution-doped films, with sequentially doped films processed to exclude dopant anions from polymer crystallites showing the highest conductivities. In conclusion, we propose a mechanism for doping induced aggregation in which the shift of the polymer HOMO level upon aggregation couples ionization and solvation energies. To show that the methodology is widely applicable, we demonstrate that several different polymer:dopant systems can be prepared by sequential doping.« less

Comparison of solution-mixed and sequentially processed P3HT: F4TCNQ films: effect of doping-induced aggregation on film morphology

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

Jacobs, Ian E.; Aasen, Erik W.; Oliveira, Julia L.

Doping polymeric semiconductors often drastically reduces the solubility of the polymer, leading to difficulties in processing doped films. Here, we compare optical, electrical, and morphological properties of P3HT films doped with F4TCNQ, both from mixed solutions and using sequential solution processing with orthogonal solvents. We demonstrate that sequential doping occurs rapidly (<1 s), and that the film doping level can be precisely controlled by varying the concentration of the doping solution. Furthermore, the choice of sequential doping solvent controls whether dopant anions are included or excluded from polymer crystallites. Atomic force microscopy (AFM) reveals that sequential doping produces significantly moremore » uniform films on the nanoscale than the mixed-solution method. In addition, we show that mixed-solution doping induces the formation of aggregates even at low doping levels, resulting in drastic changes to film morphology. Sequentially coated films show 3–15 times higher conductivities at a given doping level than solution-doped films, with sequentially doped films processed to exclude dopant anions from polymer crystallites showing the highest conductivities. In conclusion, we propose a mechanism for doping induced aggregation in which the shift of the polymer HOMO level upon aggregation couples ionization and solvation energies. To show that the methodology is widely applicable, we demonstrate that several different polymer:dopant systems can be prepared by sequential doping.« less

Mixing modes in a population-based interview survey: comparison of a sequential and a concurrent mixed-mode design for public health research.

PubMed

Mauz, Elvira; von der Lippe, Elena; Allen, Jennifer; Schilling, Ralph; Müters, Stephan; Hoebel, Jens; Schmich, Patrick; Wetzstein, Matthias; Kamtsiuris, Panagiotis; Lange, Cornelia

2018-01-01

Population-based surveys currently face the problem of decreasing response rates. Mixed-mode designs are now being implemented more often to account for this, to improve sample composition and to reduce overall costs. This study examines whether a concurrent or sequential mixed-mode design achieves better results on a number of indicators of survey quality. Data were obtained from a population-based health interview survey of adults in Germany that was conducted as a methodological pilot study as part of the German Health Update (GEDA). Participants were randomly allocated to one of two surveys; each of the surveys had a different design. In the concurrent mixed-mode design ( n  = 617) two types of self-administered questionnaires (SAQ-Web and SAQ-Paper) and computer-assisted telephone interviewing were offered simultaneously to the respondents along with the invitation to participate. In the sequential mixed-mode design ( n  = 561), SAQ-Web was initially provided, followed by SAQ-Paper, with an option for a telephone interview being sent out together with the reminders at a later date. Finally, this study compared the response rates, sample composition, health indicators, item non-response, the scope of fieldwork and the costs of both designs. No systematic differences were identified between the two mixed-mode designs in terms of response rates, the socio-demographic characteristics of the achieved samples, or the prevalence rates of the health indicators under study. The sequential design gained a higher rate of online respondents. Very few telephone interviews were conducted for either design. With regard to data quality, the sequential design (which had more online respondents) showed less item non-response. There were minor differences between the designs in terms of their costs. Postage and printing costs were lower in the concurrent design, but labour costs were lower in the sequential design. No differences in health indicators were found between the two designs. Modelling these results for higher response rates and larger net sample sizes indicated that the sequential design was more cost and time-effective. This study contributes to the research available on implementing mixed-mode designs as part of public health surveys. Our findings show that SAQ-Paper and SAQ-Web questionnaires can be combined effectively. Sequential mixed-mode designs with higher rates of online respondents may be of greater benefit to studies with larger net sample sizes than concurrent mixed-mode designs.

Learning style and teaching method preferences of Saudi students of physical therapy

PubMed Central

Al Maghraby, Mohamed A.; Alshami, Ali M.

2013-01-01

Context: To the researchers’ knowledge, there are no published studies that have investigated the learning styles and preferred teaching methods of physical therapy students in Saudi Arabia. Aim: The study was conducted to determine the learning styles and preferred teaching methods of Saudi physical therapy students. Settings and Design: A cross-sectional study design. Materials and Methods: Fifty-three Saudis studying physical therapy (21 males and 32 females) participated in the study. The principal researcher gave an introductory lecture to explain the different learning styles and common teaching methods. Upon completion of the lecture, questionnaires were distributed, and were collected on completion. Statistical Analysis Used: Percentages were calculated for the learning styles and teaching methods. Pearson’s correlations were performed to investigate the relationship between them. Results: More than 45 (85%) of the students rated hands-on training as the most preferred teaching method. Approximately 30 (57%) students rated the following teaching methods as the most preferred methods: “Advanced organizers,” “demonstrations,” and “multimedia activities.” Although 31 (59%) students rated the concrete-sequential learning style the most preferred, these students demonstrated mixed styles on the other style dimensions: Abstract-sequential, abstract-random, and concrete-random. Conclusions: The predominant concrete-sequential learning style is consistent with the most preferred teaching method (hands-on training). The high percentage of physical therapy students whose responses were indicative of mixed learning styles suggests that they can accommodate multiple teaching methods. It is recommended that educators consider the diverse learning styles of the students and utilize a variety of teaching methods in order to promote an optimal learning environment for the students. PMID:24672278

An apparatus for sequentially combining microvolumes of reagents by infrasonic mixing.

PubMed

Camien, M N; Warner, R C

1984-05-01

A method employing high-speed infrasonic mixing for obtaining timed samples for following the progress of a moderately rapid chemical reaction is described. Drops of 10 to 50 microliter each of two reagents are mixed to initiate the reaction, followed, after a measured time interval, by mixing with a drop of a third reagent to quench the reaction. The method was developed for measuring the rate of denaturation of covalently closed, circular DNA in NaOH at several temperatures. For this purpose the timed samples were analyzed by analytical ultracentrifugation. The apparatus was tested by determination of the rate of hydrolysis of 2,4-dinitrophenyl acetate in an alkaline buffer. The important characteristics of the method are (i) it requires very small volumes of sample and reagents; (ii) the components of the reaction mixture are pre-equilibrated and mixed with no transfer outside the prescribed constant temperature environment; (iii) the mixing is very rapid; and (iv) satisfactorily precise measurements of relatively short time intervals (approximately 2 sec minimum) between sequential mixings of the components are readily obtainable.

Alternative Certification Programs & Pre-Service Teacher Preparedness

ERIC Educational Resources Information Center

Koehler, Adrie; Feldhaus, Charles Robert; Fernandez, Eugenia; Hundley, Stephen

2013-01-01

This explanatory sequential mixed methods research study investigated motives and purpose exhibited by professionals transitioning from careers in science, technology, engineering and math (STEM) to secondary education. The study also analyzed personal perceptions of teaching preparedness, and explored barriers to successful teaching. STEM career…

Educator Perspectives on the Use of Alternative Assessment Methods within Taught Masters Programmes: An Exploratory Study Using Activity Theory and Q Methodology

ERIC Educational Resources Information Center

Deignan, Tim; Brown, Sally

2016-01-01

This article reports on an exploratory two-stage sequential mixed methods research study that investigated the views of university educators on the introduction of assessment methods other than essays, exams and dissertations within taught Masters programmes. In the first stage, interviews were conducted internationally with 45 participants and…

Evidence for decreased interaction and improved carotenoid bioavailability by sequential delivery of a supplement.

PubMed

Salter-Venzon, Dawna; Kazlova, Valentina; Izzy Ford, Samantha; Intra, Janjira; Klosner, Allison E; Gellenbeck, Kevin W

2017-05-01

Despite the notable health benefits of carotenoids for human health, the majority of human diets worldwide are repeatedly shown to be inadequate in intake of carotenoid-rich fruits and vegetables, according to current health recommendations. To address this deficit, strategies designed to increase dietary intakes and subsequent plasma levels of carotenoids are warranted. When mixed carotenoids are delivered into the intestinal tract simultaneously, competition occurs for micelle formation and absorption, affecting carotenoid bioavailability. Previously, we tested the in vitro viability of a carotenoid mix designed to deliver individual carotenoids sequentially spaced from one another over the 6 hr transit time of the human upper gastrointestinal system. We hypothesized that temporally and spatially separating the individual carotenoids would reduce competition for micelle formation, improve uptake, and maximize efficacy. Here, we test this hypothesis in a double-blind, repeated-measure, cross-over human study with 12 subjects by comparing the change of plasma carotenoid levels for 8 hr after oral doses of a sequentially spaced carotenoid mix, to a matched mix without sequential spacing. We find the carotenoid change from baseline, measured as area under the curve, is increased following consumption of the sequentially spaced mix compared to concomitant carotenoids delivery. These results demonstrate reduced interaction and regulation between the sequentially spaced carotenoids, suggesting improved bioavailability from a novel sequentially spaced carotenoid mix.

An exploratory sequential design to validate measures of moral emotions.

PubMed

Márquez, Margarita G; Delgado, Ana R

2017-05-01

This paper presents an exploratory and sequential mixed methods approach in validating measures of knowledge of the moral emotions of contempt, anger and disgust. The sample comprised 60 participants in the qualitative phase when a measurement instrument was designed. Item stems, response options and correction keys were planned following the results obtained in a descriptive phenomenological analysis of the interviews. In the quantitative phase, the scale was used with a sample of 102 Spanish participants, and the results were analysed with the Rasch model. In the qualitative phase, salient themes included reasons, objects and action tendencies. In the quantitative phase, good psychometric properties were obtained. The model fit was adequate. However, some changes had to be made to the scale in order to improve the proportion of variance explained. Substantive and methodological im-plications of this mixed-methods study are discussed. Had the study used a single re-search method in isolation, aspects of the global understanding of contempt, anger and disgust would have been lost.

The Complexities of Teachers' Commitment to Environmental Education: A Mixed Methods Approach

ERIC Educational Resources Information Center

Sosu, Edward M.; McWilliam, Angus; Gray, Donald S.

2008-01-01

This article argues that a mixed methods approach is useful in understanding the complexity that underlies teachers' commitment to environmental education. Using sequential and concurrent procedures, the authors demonstrate how different methodological approaches highlighted different aspects of teacher commitment. The quantitative survey examined…

Orchestrating Mathematical Discourse: Affordances and Hindrances for Novice Elementary Teachers

ERIC Educational Resources Information Center

Lee, Carrie Wilkerson

2016-01-01

The purpose of this study was to examine the mathematical discourse within novice elementary teachers' classrooms. More specifically, this study employed a sequential, explanatory mixed methods design to first quantitatively analyze the relationship between teachers' discourse practices and teacher attributes and school context. Next, a…

The Impact of Generational Differences on Organizational Relationships: A Communication Perspective

ERIC Educational Resources Information Center

Salahuddin, Mecca M.

2013-01-01

The purpose of this mixed methods sequential explanatory study was to investigate the relationship between an individual's generation and the communication styles used with other generations, and explore the influence of intergenerational communication styles on organizational relationships. The study utilized the Global Perceptions of…

Trainee Teachers' Experience of Reflection

ERIC Educational Resources Information Center

McKenzie, Liz

2015-01-01

This article reports an investigation of trainee teachers' experience of reflection whilst undertaking a teaching qualification for the post-compulsory sector. The study used a sequential, mixed-methods design, employing a structured questionnaire and a semi-structured interview; 127 individuals completed the questionnaire about their experience…

The Relationship between the Emotional Intelligence of Secondary Public School Principals and School Performance

ERIC Educational Resources Information Center

Ashworth, Stephanie R.

2013-01-01

The study examined the relationship between secondary public school principals' emotional intelligence and school performance. The correlational study employed an explanatory sequential mixed methods model. The non-probability sample consisted of 105 secondary public school principals in Texas. The emotional intelligence characteristics of the…

An Inquiry into Workplace Incivility: Perceptions of Working Graduate Students

ERIC Educational Resources Information Center

Greene, Ashley E.

2012-01-01

The purpose of this sequential mixed methods study was to examine and determine the level of incivility in the workplace as a growing problem from the perceptional views of graduate students enrolled in accelerated degree programs for graduate studies in Business Administration, Criminal Justice Administration, Gerontology, Health Management, and…

Developing a Web-Based Hiring Resource at a State Medical College

ERIC Educational Resources Information Center

Drane, Daniel, III

2017-01-01

This study uses a sequential, mixed method, action research, quantitative to qualitative research design. The purpose of this study was to develop a useful standardized hiring process at a state medical college that brings clarity to the hiring process and policies. Two conceptual frameworks guided the innovations in this study--communities of…

A Study on Becoming an Alternatively Certified Career and Technical Educator

ERIC Educational Resources Information Center

Cotton-Flanagan, Kymberli A.

2011-01-01

This mixed method study examined the perspectives of twelve practicing high school CTE teachers engaged in a newly approved university model for alternative certification. Using Creswell's (2008) Sequential Exploratory Design and the lens of adult learning theory as established in Knowles' (1970) Theory of Andragogy, this study examines how…

Mixing a Grounded Theory Approach with a Randomized Controlled Trial Related to Intimate Partner Violence: What Challenges Arise for Mixed Methods Research?

PubMed Central

Catallo, Cristina; Jack, Susan M.; Ciliska, Donna; MacMillan, Harriet L.

2013-01-01

Little is known about how to systematically integrate complex qualitative studies within the context of randomized controlled trials. A two-phase sequential explanatory mixed methods study was conducted in Canada to understand how women decide to disclose intimate partner violence in emergency department settings. Mixing a RCT (with a subanalysis of data) with a grounded theory approach required methodological modifications to maintain the overall rigour of this mixed methods study. Modifications were made to the following areas of the grounded theory approach to support the overall integrity of the mixed methods study design: recruitment of participants, maximum variation and negative case sampling, data collection, and analysis methods. Recommendations for future studies include: (1) planning at the outset to incorporate a qualitative approach with a RCT and to determine logical points during the RCT to integrate the qualitative component and (2) consideration for the time needed to carry out a RCT and a grounded theory approach, especially to support recruitment, data collection, and analysis. Data mixing strategies should be considered during early stages of the study, so that appropriate measures can be developed and used in the RCT to support initial coding structures and data analysis needs of the grounded theory phase. PMID:23577245

Science Teacher Education in the Twenty-First Century: A Pedagogical Framework for Technology-Integrated Social Constructivism

ERIC Educational Resources Information Center

Barak, Miri

2017-01-01

Changes in our global world have shifted the skill demands from acquisition of structured knowledge to mastery of skills, often referred to as twenty-first century competencies. Given these changes, a sequential explanatory mixed methods study was undertaken to (a) examine predominant instructional methods and technologies used by teacher…

Factors, Practices, and Policies Influencing Students' Upward Transfer to Baccalaureate-Degree Programs and Institutions: A Mixed Methods Analysis

ERIC Educational Resources Information Center

LaSota, Robin Rae

2013-01-01

My dissertation utilizes an explanatory, sequential mixed-methods research design to assess factors influencing community college students' transfer probability to baccalaureate-granting institutions and to present promising practices in colleges and states directed at improving upward transfer, particularly for low-income and first-generation…

An Emic, Mixed-Methods Approach to Defining and Measuring Positive Parenting among Low-Income Black Families

ERIC Educational Resources Information Center

McWayne, Christine M.; Mattis, Jacqueline S.; Green Wright, Linnie E.; Limlingan, Maria Cristina; Harris, Elise

2017-01-01

Research Findings: This within-group exploratory sequential mixed-methods investigation sought to identify how ethnically diverse, urban-residing, low-income Black families conceptualize positive parenting. During the item development phase 119 primary caregivers from Head Start programs participated in focus groups and interviews. These…

Terminate Lung Cancer (TLC) Study - A mixed-methods population approach to increase lung cancer screening awareness and low-dose computed tomography in Eastern Kentucky

PubMed Central

Cardarelli, Roberto; Reese, David; Roper, Karen L.; Cardarelli, Kathryn; Feltner, Frances J.; Studts, Jamie L.; Knight, Jennifer R.; Armstrong, Debra; Weaver, Anthony; Shaffer, Dana

2017-01-01

For low dose CT lung cancer screening to be effective in curbing disease mortality, efforts are needed to overcome barriers to awareness and facilitate uptake of the current evidence-based screening guidelines. A sequential mixed-methods approach was employed to design a screening campaign utilizing messages developed from community focus groups, followed by implementation of the outreach campaign intervention in two high-risk Kentucky regions. This study reports on rates of awareness and screening in intervention regions, as compared to a control region. PMID:27866066

Distance Education and Organizational Environment

ERIC Educational Resources Information Center

East, Jean F.; LaMendola, Walter; Alter, Catherine

2014-01-01

As distance education models in social work education continue to grow, this study addresses prevalence and type of models in graduate social work programs and the perceptions of deans about the future of e-learning models of curriculum delivery. The study was an exploratory sequential mixed-methods design including a national survey of 121…

The Relationships between Language Learning Strategies and Positive Emotions among Malaysian ESL Undergraduates

ERIC Educational Resources Information Center

Mohammadipour, Mohammad; Rashid, Sabariah Md; Rafik-Galea, Shameem; Thai, Yap Ngee

2018-01-01

Emotions are an indispensable part of second language learning. The aim of this study is to determine the relationship between the use of language learning strategies and positive emotions. The present study adopted a sequential mixed methods design. The participants were 300 Malaysian ESL undergraduates selected through stratified random sampling…

Special Education Administrators: Who and What Helps Buffer Job-Related Stress?

ERIC Educational Resources Information Center

Wheeler, Deborah S.; LaRocco, Diana J.

2009-01-01

The purpose of this study was to describe special education administrators' reports of the social supports (House, 1981) that ameliorate the stress inherent in their professional role. This study used a mixed methods design and was conducted in two sequential phases involving 153 special education administrators in a northeastern state. During…

The Role of Attitudes in the Development of Russian as a Foreign Language: A Retrospective Study

ERIC Educational Resources Information Center

Bátyi, Szilvia

2017-01-01

The article reports the findings of a retrospective study which looked at Hungarian learners' attitudes towards Russian people, the Russian language and teachers of Russian. Mixed-methods sequential explanatory design (Ivankova, Creswell, & Stick, 2006) was applied which combines the collection and analysis of quantitative and qualitative data…

Superintendent Leadership and Student Achievement in Suburban High Schools: A Sequential Explanatory Mixed Methods Analysis

ERIC Educational Resources Information Center

Kellner, Steven Reese

2012-01-01

This research study explored the critical nature of the connection between student achievement and superintendent leadership. A great deal of scholarship has addressed either student achievement or leadership and previous evidence has suggested the impact of both parental education and racioethnicity on student achievement, but few studies have…

Adult Learners' Knowledge of Fraction Addition and Subtraction

ERIC Educational Resources Information Center

Muckridge, Nicole A.

2017-01-01

The purpose of this study was to examine adult developmental mathematics (ADM) students' knowledge of fraction addition and subtraction as it relates to their demonstrated fraction schemes and ability to disembed in multiplicative contexts with whole numbers. The study was conducted using a mixed methods sequential explanatory design. In the first…

Over the Hurdles: Barriers to Social Media Use in Extension Offices

ERIC Educational Resources Information Center

Newbury, Elizabeth; Humphreys, Lee; Fuess, Lucas

2014-01-01

The research reported here explored the perceived barriers to social media use by Extension educators. Using a sequential mixed method approach, the research was composed of two parts. The qualitative study used interview data (n = 27) from Wisconsin and New York Extension educators. The quantitative study gathered data from surveying Extension…

Life in the Middle: An Exploratory Study of California Community College Instructional Deans

ERIC Educational Resources Information Center

Sill, Nancy

2014-01-01

This two-phase sequential mixed methods exploratory study examined the perceived skill deficits of instructional deans at California community colleges to better understand the training and development needs that are necessary to support dean success and to prepare them for advancement in a timelier manner. This study is grounded in the…

Using mixed methods effectively in prevention science: designs, procedures, and examples.

PubMed

Zhang, Wanqing; Watanabe-Galloway, Shinobu

2014-10-01

There is growing interest in using a combination of quantitative and qualitative methods to generate evidence about the effectiveness of health prevention, services, and intervention programs. With the emerging importance of mixed methods research across the social and health sciences, there has been an increased recognition of the value of using mixed methods for addressing research questions in different disciplines. We illustrate the mixed methods approach in prevention research, showing design procedures used in several published research articles. In this paper, we focused on two commonly used mixed methods designs: concurrent and sequential mixed methods designs. We discuss the types of mixed methods designs, the reasons for, and advantages of using a particular type of design, and the procedures of qualitative and quantitative data collection and integration. The studies reviewed in this paper show that the essence of qualitative research is to explore complex dynamic phenomena in prevention science, and the advantage of using mixed methods is that quantitative data can yield generalizable results and qualitative data can provide extensive insights. However, the emphasis of methodological rigor in a mixed methods application also requires considerable expertise in both qualitative and quantitative methods. Besides the necessary skills and effective interdisciplinary collaboration, this combined approach also requires an open-mindedness and reflection from the involved researchers.

Applications of mixed-methods methodology in clinical pharmacy research.

PubMed

Hadi, Muhammad Abdul; Closs, S José

2016-06-01

Introduction Mixed-methods methodology, as the name suggests refers to mixing of elements of both qualitative and quantitative methodologies in a single study. In the past decade, mixed-methods methodology has gained popularity among healthcare researchers as it promises to bring together the strengths of both qualitative and quantitative approaches. Methodology A number of mixed-methods designs are available in the literature and the four most commonly used designs in healthcare research are: the convergent parallel design, the embedded design, the exploratory design, and the explanatory design. Each has its own unique advantages, challenges and procedures and selection of a particular design should be guided by the research question. Guidance on designing, conducting and reporting mixed-methods research is available in the literature, so it is advisable to adhere to this to ensure methodological rigour. When to use it is best suited when the research questions require: triangulating findings from different methodologies to explain a single phenomenon; clarifying the results of one method using another method; informing the design of one method based on the findings of another method, development of a scale/questionnaire and answering different research questions within a single study. Two case studies have been presented to illustrate possible applications of mixed-methods methodology. Limitations Possessing the necessary knowledge and skills to undertake qualitative and quantitative data collection, analysis, interpretation and integration remains the biggest challenge for researchers conducting mixed-methods studies. Sequential study designs are often time consuming, being in two (or more) phases whereas concurrent study designs may require more than one data collector to collect both qualitative and quantitative data at the same time.

The Facilitators and Barriers to Nurses’ Participation in Continuing Education Programs: A Mixed Method Explanatory Sequential Study

PubMed Central

Shahhosseini, Zohreh; Hamzehgardeshi, Zeinab

2015-01-01

Background: Since several factors affect nurses’ participation in Continuing Education, and that nurses’ Continuing Education affects patients’ and community health status, it is essential to know facilitators and barriers of participation in Continuing Education programs and plan accordingly. This mixed approach study aimed to investigate the facilitators and barriers of nurses’ participation, to explore nurses’ perception of the most common facilitators and barriers. Methods: An explanatory sequential mixed methods design with follow up explanations variant were used, and it involved collecting quantitative data (361 nurses) first and then explaining the quantitative results with in-depth interviews during a qualitative study. Results: The results showed that the mean score of facilitators to nurses’ participation in Continuing Education was significantly higher than the mean score of barriers (61.99±10.85 versus 51.17±12.83; p<0.001, t=12.23). The highest mean score of facilitators of nurses’ participation in Continuing Education was related to “Update my knowledge”. By reviewing the handwritings in qualitative phase, two main levels of updating information and professional skills were extracted as the most common facilitators and lack of support as the most common barrier to nurses’ participation in continuing education program. Conclusion: According to important role Continuing Education on professional skills, nurse managers should facilitate the nurse’ participation in the Continues Education. PMID:25948439

Reproductive practices by patterns of marriage among Iranian women: study protocol for an explanatory sequential mixed methods design.

PubMed

Taghizadeh, Ziba; Vedadhir, Abouali; Behmanesh, Fereshteh; Ebadi, Abbas; Pourreza, Abulghasem; Abbasi-Shavazi, Mohammad Jalal

2015-09-18

Nowadays, nearly half of the world population lives in societies with low fertility or the below-replacement fertility. This potentially grounds the critical situation of reduction in the workforce and causes the aging of population due to an overall increase in life expectancy and standard of living. Hence, population and its transitions including the issue of fertility decline has become a topic of intense debate in the agenda-setting and policy-making processes in both the developed and developing countries. In this view, what can practically be done to respond to the fertility decline that entails effectively addressing the determinants of fertility change? In line with the literature, how people form their marriages or patterns of marriage is amongst influencing factors which potentially affect their reproductive practices as diverse societies recognize different conventions for marriage. This study is to examine women's reproductive practices by the various patterns of marriage using the explanatory sequential mixed methods design. This study has an explanatory sequential mixed methods design, the follow-up explanations variant model, with two strands. This design will be implemented in two distinct phases. In the first phase, a cross-sectional quantitative study will be done using a cluster sampling strategy on 850 married women 15-49 years old living in Babol city, Iran. In order to obtain a deeper understanding of the results of the quantitative phase, researchers will implement a qualitative research in the second phase of this study. This design will provide an explanation of the quantitative research results using the qualitative evidence. As patterns of marriage have implications for the status of women, their health and fertility, the result of this study can provide a rich source of information for the required health-related interventions and policies are required to put the demographic changes on the right track at micro and macro level and improve the reproductive practices of women at micro level.

Associations between Children's Physical Activities, Sedentary Behaviours and Family Structure: A Sequential Mixed Methods Approach

ERIC Educational Resources Information Center

Quarmby, T.; Dagkas, S.; Bridge, M.

2011-01-01

This mixed method paper explored the effect of family structure on children's physical activities and sedentary pursuits. It furthers the limited understanding of how family structure impacts on children's time in, and reasons behind engaging in, certain physical activities. Children from three inner city comprehensive schools in the Midlands,…

"What about People Our Age?" Applying Qualitative and Quantitative Methods to Uncover How Political Ads Alienate College Students

ERIC Educational Resources Information Center

Parmelee, John H.; Perkins, Stephynie C.; Sayre, Judith J.

2007-01-01

This study uses a sequential transformative mixed methods research design to explain how political advertising fails to engage college students. Qualitative focus groups examined how college students interpret the value of political advertising to them, and a quantitative manifest content analysis concerning ad framing of more than 100 ads from…

Trainees' Perceptions on Supervisor Factors That Influence Transfer of Training

ERIC Educational Resources Information Center

Fagan, Sharon Lee

2017-01-01

A midsize nonprofit blood bank organization is experiencing a high percentage of supervisors and managers not transferring skills taught in leadership development training programs back to the workplace. The purpose of this mixed methods, sequential, explanatory study was to understand the relationship between supervisor support or opposition and…

The Role of Principals in Professional Learning Communities

ERIC Educational Resources Information Center

Buttram, Joan L.; Farley-Ripple, Elizabeth N.

2016-01-01

The purpose of this article is to identify how principals shape the adoption and implementation of professional learning communities. The study employed a sequential mixed-methods approach in which interviews, observations, and document analysis informed survey design. Teachers were surveyed in four elementary schools about the practices and…

Chinese Placement Procedures at U.S. Postsecondary Institutions

ERIC Educational Resources Information Center

Wei, Miaochun

2017-01-01

This quant-QUAL sequential explanatory mixed methods study describes a framework for evaluating the communicative competence (Canale & Swain, 1980; Canale, 1983) of non-beginner students of Chinese for placement purposes at U.S. four-year postsecondary institutions. A pragmatic lens was used to collect and analyze data that generated a…

The Science ELF: Assessing the Enquiry Levels Framework as a Heuristic for Professional Development

ERIC Educational Resources Information Center

Wheeler, Lindsay B.; Bell, Randy L.; Whitworth, Brooke A.; Maeng, Jennifer L.

2015-01-01

This study utilized an explanatory sequential mixed methods approach to explore randomly assigned treatment and control participants' frequency of inquiry instruction in secondary science classrooms. Eleven treatment participants received professional development (PD) that emphasized a structured approach to inquiry instruction, while 10 control…

Teacher and Peer Support for Young Adolescents' Motivation, Engagement, and School Belonging

ERIC Educational Resources Information Center

Kiefer, Sarah M.; Alley, Kathleen M.; Ellerbrock, Cheryl R.

2015-01-01

The purpose of this sequential explanatory mixed methods study was to investigate teacher and peer support for young adolescents' academic motivation, classroom engagement, and school belonging within one large, urban, ethnically diverse middle school. In the initial quantitative phase, associations among aspects of teacher support (autonomy,…

Behavioral and Academic Differences between an Inclusive and Non-Inclusive Classroom

ERIC Educational Resources Information Center

Hatch, Sherry Lynn

2013-01-01

Although educators continue to provide all students access to their grade-level curriculum, students with disabilities are not performing academically in accordance with state standards. The purpose of this sequential transformative mixed methods study was to investigate academic and/or behavioral differences between an inclusion classroom and a…

Middle School Educators' Perceptions of Online Professional Development

ERIC Educational Resources Information Center

Theodocion, Kelley E.

2012-01-01

Numerous researchers have investigated distance education in postsecondary settings, but there is a paucity of research regarding the design and delivery of online professional development for K-12 educators. The goal of this mixed methods sequential exploratory study was to examine attitudes of middle grades educators toward an online…

The Effectiveness of Project-Based Learning on Mathematics Proficiency with African American Students

ERIC Educational Resources Information Center

Jenkins, Justina

2017-01-01

This sequential exploratory mixed methods study addressed the problem of low academic achievement in mathematics, specifically for African American middle school students who historically score below proficient levels on standardized mathematics assessments. The purpose was to investigate the effectiveness of the Project-Based Learning (PBL)…

Inquiry-Based Instruction: Does School Environmental Context Matter?

ERIC Educational Resources Information Center

Pea, Celestine H.

2012-01-01

In a larger study on teachers' beliefs about science teaching, one component looks at how school environmental context factors influence inquiry-based science instruction. Research shows that three broad categories of school environmental factors (human, sociocultural, design) impact inquiry-based teaching in some way. A mixed-method, sequential,…

Leadership Self-Efficacy in University Co-Curricular Programs

ERIC Educational Resources Information Center

Fields, Andrew R.

2010-01-01

University educators are concerned with student leadership development in order to generate much-needed leaders in every aspect of society. This sequential mixed methods study found that students who participate in a university co-curricular outdoor education leadership training program, combined with the experience of leading a wilderness…

The Relationship between Building Teacher Leadership Capacity and Campus Culture

ERIC Educational Resources Information Center

Harris, Dawn R.; Kemp-Graham, Kriss Y.

2017-01-01

The purpose of this explanatory sequential mixed methods research study was to explore the relationship between building teacher leadership capacity and campus culture in a suburban East Texas school district. Developing teacher leaders by building leadership capacity depends on administrators' abilities to develop leaders from within the existing…

Evaluation of Educational Administration: A Decade Review of Research (2001-2010)

ERIC Educational Resources Information Center

Parylo, Oksana

2012-01-01

This sequential mixed methods study analyzed how program evaluation was used to assess educational administration and examined thematic trends in educational evaluation published over 10 years (2001-2010). First, qualitative content analysis examined the articles in eight peer-reviewed evaluation journals. This analysis revealed that numerous…

An Exploration of Elementary Teachers' Beliefs and Perceptions About Science Inquiry: A Mixed Methods Study

NASA Astrophysics Data System (ADS)

Hamadeh, Linda

In order for science-based inquiry instruction to happen on a large scale in elementary classrooms across the country, evidence must be provided that implementing this reform can be realistic and practical, despite the challenges and obstacles teachers may face. This study sought to examine elementary teachers' knowledge and understanding of, attitudes toward, and overall perceptions of inquiry-based science instruction, and how these beliefs influenced their inquiry practice in the classroom. It offered a description and analysis of the approaches elementary science teachers in Islamic schools reported using to promote inquiry within the context of their science classrooms, and addressed the challenges the participating teachers faced when implementing scientific inquiry strategies in their instruction. The research followed a mixed method approach, best described as a sequential two-strand design (Teddlie & Tashakkori, 2006). Sequential mixed designs develop two methodological strands that occur chronologically, and in the case of this research, QUAN→QUAL. Findings from the study supported the notion that the school and/or classroom environment could be a contextual factor that influenced some teachers' classroom beliefs about the feasibility of implementing science inquiry. Moreover, although teacher beliefs are influential, they are malleable and adaptable and influenced primarily by their own personal direct experiences with inquiry instruction or lack of.

Nonsteady Problem for an Elastic Half-Plane with Mixed Boundary Conditions

NASA Astrophysics Data System (ADS)

Kubenko, V. D.

2016-03-01

An approach to studying nonstationary wave processes in an elastic half-plane with mixed boundary conditions of the fourth boundary-value problem of elasticity is proposed. The Laplace and Fourier transforms are used. The sequential inversion of these transforms or the inversion of the joint transform by the Cagniard method allows obtaining the required solution (stresses, displacements) in a closed analytic form. With this approach, the problem can be solved for various types of loads

Evaluating Bias of Sequential Mixed-Mode Designs against Benchmark Surveys

ERIC Educational Resources Information Center

Klausch, Thomas; Schouten, Barry; Hox, Joop J.

2017-01-01

This study evaluated three types of bias--total, measurement, and selection bias (SB)--in three sequential mixed-mode designs of the Dutch Crime Victimization Survey: telephone, mail, and web, where nonrespondents were followed up face-to-face (F2F). In the absence of true scores, all biases were estimated as mode effects against two different…

The Effect of Portfolio Assessments on Metacognitive Skills and on Attitudes toward a Course

ERIC Educational Resources Information Center

Gencel, Ilke Evin

2017-01-01

The aim of this study is to determine through teacher candidates' thoughts the effects of a portfolio assessment implementation on their metacognitive skills and attitudes towards a course on measurement and evaluation. Exploratory sequential mixed-methods design is employed within the study. The pretest/posttest control group design was used in…

Students' Preferences and Opinions on Design of a Mobile Marketing Education Application

ERIC Educational Resources Information Center

Ozata, Zeynep; Ozdama Keskin, Nilgun

2014-01-01

The purpose of this study was to define and better understand business school students' opinions and preferences on the design of a mobile marketing education application. To accomplish this purpose an explanatory mixed methods study design was used and the data was collected sequentially. First, a questionnaire was conducted with 168 business…

A Case Study of Student Assessment Programs in a College of Business Administration at a Southern HBCU

ERIC Educational Resources Information Center

Bell Haynes, Janel Elizabeth

2013-01-01

The purpose of this mixed method sequential explanatory case study was to describe the relationship of a student outcomes assessment program, as measured by the Peregrine Academic Leveling Course, (ALC), to the academic performance, determined by scores on the Peregrine Common Professional Component (CPC) examination, of students enrolled during…

Motivating Factors for Teaching and Studying Music at Two-Year Colleges: A Survey of Faculty and Students

ERIC Educational Resources Information Center

Stewart, John R.; Williams, Yolanda Y.; Vu, Kinh T.; Collins, Tracey R.; Clementson, Casey J.; Berberick, David M.

2015-01-01

The purpose of this study was to explore what motivates faculty and student involvement in this educational environment and how student participation in music coursework contributes to current musical endeavors. The research team utilized a modified explanatory sequential mixed methods design to collect survey data and focus group data from…

Relationship between Teacher Knowledge of Concepts and Connections, Teaching Practice, and Student Achievement in Middle Grades Mathematics

ERIC Educational Resources Information Center

Tchoshanov, Mourat A.

2011-01-01

The mixed method sequential nested study examines whether and how the cognitive type of teachers' content knowledge is associated with student achievement, and correlated with teaching practice. In the context of this study, the "cognitive type" refers to the kind of teacher content knowledge and thinking processes required to accomplish…

Enhancing Science Education through Extracurricular Activities: A Retrospective Study of "Suzy Science and the Whiz Kids[C]"

ERIC Educational Resources Information Center

Kralina, Linda M.

2009-01-01

Extracurricular activities (ECA) are informal settings offering free-choice experiences that are generally voluntary, open-ended, non-sequential, self-directed, hands-on, and evaluation-free. This mixed methods study investigates participation in a high school science ECA by collecting the memories of former student members for their perceptions…

Examining the Relationship between Classroom Climate and Student Achievement of Middle School Students

ERIC Educational Resources Information Center

Barksdale, Christopher J.

2017-01-01

The purpose of this sequential mixed method study was to examine the relationship between classroom climate and student achievement of middle school students. This study included a review of data collected from the Learning Environment Inventory from a purposeful sample of middle school students from a large suburban school district. A purposeful…

Importance and Effectiveness of Student Health Services at a South Texas University

ERIC Educational Resources Information Center

McCaig, Marilyn M.

2013-01-01

The study examined the health needs of students at a south Texas university and documented the utility of the student health center. The descriptive study employed a mixed methods explanatory sequential design (ESD). The non-probability sample consisted of 140 students who utilized the university's health center during the period of March 23-30,…

Patterns of Teacher's Instructional Moves: What Makes Mathematical Instructional Practices Unique?

ERIC Educational Resources Information Center

Pinter, Holly Henderson

2013-01-01

The purpose of this study was to examine patterns in fourth-grade teachers' use of instructional moves in the implementation of standards-based mathematical teaching practices. Using a mixed methods sequential explanatory design, the study consisted of two phases: quantitative selection and qualitative analysis. The first phase of the study…

Designing a mixed methods study in primary care.

PubMed

Creswell, John W; Fetters, Michael D; Ivankova, Nataliya V

2004-01-01

Mixed methods or multimethod research holds potential for rigorous, methodologically sound investigations in primary care. The objective of this study was to use criteria from the literature to evaluate 5 mixed methods studies in primary care and to advance 3 models useful for designing such investigations. We first identified criteria from the social and behavioral sciences to analyze mixed methods studies in primary care research. We then used the criteria to evaluate 5 mixed methods investigations published in primary care research journals. Of the 5 studies analyzed, 3 included a rationale for mixing based on the need to develop a quantitative instrument from qualitative data or to converge information to best understand the research topic. Quantitative data collection involved structured interviews, observational checklists, and chart audits that were analyzed using descriptive and inferential statistical procedures. Qualitative data consisted of semistructured interviews and field observations that were analyzed using coding to develop themes and categories. The studies showed diverse forms of priority: equal priority, qualitative priority, and quantitative priority. Data collection involved quantitative and qualitative data gathered both concurrently and sequentially. The integration of the quantitative and qualitative data in these studies occurred between data analysis from one phase and data collection from a subsequent phase, while analyzing the data, and when reporting the results. We recommend instrument-building, triangulation, and data transformation models for mixed methods designs as useful frameworks to add rigor to investigations in primary care. We also discuss the limitations of our study and the need for future research.

A Mixed Methods Evaluation of a 12-Week Insurance-Sponsored Weight Management Program Incorporating Cognitive-Behavioral Counseling

ERIC Educational Resources Information Center

Abildso, Christiaan; Zizzi, Sam; Gilleland, Diana; Thomas, James; Bonner, Daniel

2010-01-01

Physical activity is critical in healthy weight loss, yet there is still much to be learned about psychosocial mechanisms of physical activity behavior change in weight loss. A sequential mixed methods approach was used to assess the physical and psychosocial impact of a 12-week cognitive-behavioral weight management program and explore factors…

Use of Appreciative Inquiry to Explore the Experiences of Faculty Advisors

ERIC Educational Resources Information Center

Myers, Valerie Ann-Marie

2013-01-01

Academic advising significantly impacts student achievement, persistence, and retention, yet it continues to be an area of weakness for many institutions. The purpose of this sequential mixed-methods case study was to explore the experiences of faculty advisors to identify strengths and weaknesses in their knowledge and skills. Appreciative…

Introducing Science Experiments to Rote-Learning Classes in Pakistani Middle Schools

ERIC Educational Resources Information Center

Pell, Anthony William; Iqbal, Hafiz Muhammad; Sohail, Shahida

2010-01-01

A mixed-methods sequential research design has been used to test the effect of introducing teacher science demonstrations to a traditional book-learning sample of 384 Grade 7 boys and girls from five schools in Lahore, Pakistan. In the quasi-experimental quantitative study, the eight classes of comparable ability were designated either…

The Implications of Learners' Goal Orientation in a Prior Learning Assessment Program

ERIC Educational Resources Information Center

McClintock, Patricia

2013-01-01

This mixed methods sequential explanatory study was designed to investigate students' persistence in an online Prior Learning Assessment (PLA) Program by researching the implications of goal orientation and other academic, institutional, and student-related factors of non-traditional students enrolled in such a program at the University of St.…

Feasibility of Adopting English-Medium Instruction at Iranian Universities

ERIC Educational Resources Information Center

Ghorbani, Mohammad Reza; Alavi, Sahar Zahed

2014-01-01

This study was an attempt to explore the potential possibilities of implementing English as the medium of instruction (EMI) at Iranian universities. The sequential exploratory mixed methods design was used to collect the perspectives of both students and content-area lecturers at the state University of Bojnord through e-mail interviews and survey…

A Critical Examination of Senior Executive Leadership Succession Planning and Management with Implications for Underrepresented Minorities

ERIC Educational Resources Information Center

Jackson, LeKeisha D.

2017-01-01

Guided by the research questions, this study utilized a sequential explanatory mixed methods research design to examine senior executive leadership succession planning at four-year, predominately white, doctoral universities in the state of Georgia. Utilizing the Representative Bureaucracy theory and the Mateso SPM conceptual model, this study…

Social Media Adoption and Use among Information Technology Professionals and Implications for Leadership

ERIC Educational Resources Information Center

Lundahl Philpot, Eva

2013-01-01

This sequential, mixed methods research addressed emerging social media use practices among IT professionals and explored lived experiences of senior IT leaders relative to successful organizational social media adoption and use. The study was informed by structuration theory and elements from the universal technology adoption and use (UTAUT)…

Exploring College Counselor Spiritual Competency in Relation to Training and Professional Practice

ERIC Educational Resources Information Center

Conley, Abigail Holland

2012-01-01

The purpose of this mixed methods sequential explanatory study was to explore factors contributing to college counselors' spiritual competency by obtaining quantitative results from surveying 199 current members of the American College Counseling Association (ACCA) and then following up with 32 purposefully selected respondents based on high…

Improved method for calibration of exchange flows for a physical transport box model of Tampa Bay, FL USA

EPA Science Inventory

Results for both sequential and simultaneous calibration of exchange flows between segments of a 10-box, one-dimensional, well-mixed, bifurcated tidal mixing model for Tampa Bay are reported. Calibrations were conducted for three model options with different mathematical expressi...

Designing A Mixed Methods Study In Primary Care

PubMed Central

Creswell, John W.; Fetters, Michael D.; Ivankova, Nataliya V.

2004-01-01

BACKGROUND Mixed methods or multimethod research holds potential for rigorous, methodologically sound investigations in primary care. The objective of this study was to use criteria from the literature to evaluate 5 mixed methods studies in primary care and to advance 3 models useful for designing such investigations. METHODS We first identified criteria from the social and behavioral sciences to analyze mixed methods studies in primary care research. We then used the criteria to evaluate 5 mixed methods investigations published in primary care research journals. RESULTS Of the 5 studies analyzed, 3 included a rationale for mixing based on the need to develop a quantitative instrument from qualitative data or to converge information to best understand the research topic. Quantitative data collection involved structured interviews, observational checklists, and chart audits that were analyzed using descriptive and inferential statistical procedures. Qualitative data consisted of semistructured interviews and field observations that were analyzed using coding to develop themes and categories. The studies showed diverse forms of priority: equal priority, qualitative priority, and quantitative priority. Data collection involved quantitative and qualitative data gathered both concurrently and sequentially. The integration of the quantitative and qualitative data in these studies occurred between data analysis from one phase and data collection from a subsequent phase, while analyzing the data, and when reporting the results. DISCUSSION We recommend instrument-building, triangulation, and data transformation models for mixed methods designs as useful frameworks to add rigor to investigations in primary care. We also discuss the limitations of our study and the need for future research. PMID:15053277

Hybrid Model Predictive Control for Sequential Decision Policies in Adaptive Behavioral Interventions.

PubMed

Dong, Yuwen; Deshpande, Sunil; Rivera, Daniel E; Downs, Danielle S; Savage, Jennifer S

2014-06-01

Control engineering offers a systematic and efficient method to optimize the effectiveness of individually tailored treatment and prevention policies known as adaptive or "just-in-time" behavioral interventions. The nature of these interventions requires assigning dosages at categorical levels, which has been addressed in prior work using Mixed Logical Dynamical (MLD)-based hybrid model predictive control (HMPC) schemes. However, certain requirements of adaptive behavioral interventions that involve sequential decision making have not been comprehensively explored in the literature. This paper presents an extension of the traditional MLD framework for HMPC by representing the requirements of sequential decision policies as mixed-integer linear constraints. This is accomplished with user-specified dosage sequence tables, manipulation of one input at a time, and a switching time strategy for assigning dosages at time intervals less frequent than the measurement sampling interval. A model developed for a gestational weight gain (GWG) intervention is used to illustrate the generation of these sequential decision policies and their effectiveness for implementing adaptive behavioral interventions involving multiple components.

The Nature, Causes and Effects of School Violence in South African High Schools

ERIC Educational Resources Information Center

Ncontsa, Vusumzi Nelson; Shumba, Almon

2013-01-01

We sought to investigate the nature, causes and effects of school violence in four South African high schools. A purposive sample of five principals, 80 learners and 20 educators was selected from the four schools used in the study. A sequential mixed method approach was used in this study; both questionnaires and interviews were used. The design…

Distributed Leadership an Instrument for School Improvement: The Study of Public Senior High Schools in Ghana

ERIC Educational Resources Information Center

Dampson, Dandy George; Havor, Felicia Mensah; Laryea, Prince

2018-01-01

The purpose of the study was to investigate the influence of distributed leadership in Public Senior High Schools (SHS) with regard to school improvement. Using the Explanatory Sequential Mixed-Method design, 92 teachers and 4 head masters and 4 assistant head masters were randomly and census sampled. Three research questions were formulated and…

A Sequential Mixed Methods Study: An Exploration of the Use of Emotional Intelligence by Senior Student Affairs Officers in Managing Critical Incidents

ERIC Educational Resources Information Center

Johnson, Brian

2013-01-01

Emotional intelligence is a relatively new academic discipline that began forming in the early 1990s. Currently, emotional intelligence is used in academia and in business as a new intelligence quotient. This research study investigates how Senior Student Affairs Officers' use their emotional intelligence ability during critical incidents. The…

Investigating the Effect of the Activities Based on Explanation Assisted REACT Strategy on Learning Impulse, Momentum and Collisions Topics

ERIC Educational Resources Information Center

Ültay, Eser; Alev, Nedim

2017-01-01

The purpose of this study was to investigate the effect of explanation assisted REACT strategy which was based on context-based learning approach on prospective science teachers' (PSTs) learning in impulse, momentum and collisions topics. The sequential explanatory strategy within mixed methods design was employed in this study. The first phase of…

Research Needs and Learning Format Preferences of Graduate Students at a Large Public University: An Exploratory Study

ERIC Educational Resources Information Center

Bussell, Hilary; Hagman, Jessica; Guder, Christopher S.

2017-01-01

This article reports on a study of research needs and learning preferences of graduate students at a public research university. A sequential exploratory mixed-method design was used, with a survey instrument developed from an initial qualitative stage. Significant differences were found between master's and doctoral students' and on-campus and…

Characteristics of Competitive Pressure Created by Charter Schools: Charter Schools, Their Impact on Traditional Public Districts and the Role of District Leadership

ERIC Educational Resources Information Center

Cummins, Cathy

2014-01-01

This mixed methods sequential explanatory designed study applied the economic theory of marketplace competition as a way to frame superintendents' perceptions of the characteristics of students and parents seeking charter schools. Although studies on charter schools are abundant, there is limited literature on this particular aspect of market…

Developing Metrics for Effective Teaching in Extension Education: A Multi-State Factor-Analytic and Psychometric Analysis of Effective Teaching

ERIC Educational Resources Information Center

McKim, Billy R.; Lawver, Rebecca G.; Enns, Kellie; Smith, Amy R.; Aschenbrener, Mollie S.

2013-01-01

To successfully educate the public about agriculture, food, and natural resources, we must have effective educators in both formal and nonformal settings. Specifically, this study, which is a valuable part of a larger sequential mixed-method study addressing effective teaching in formal and nonformal agricultural education, provides direction for…

Using mixed methods research designs in health psychology: an illustrated discussion from a pragmatist perspective.

PubMed

Bishop, Felicity L

2015-02-01

To outline some of the challenges of mixed methods research and illustrate how they can be addressed in health psychology research. This study critically reflects on the author's previously published mixed methods research and discusses the philosophical and technical challenges of mixed methods, grounding the discussion in a brief review of methodological literature. Mixed methods research is characterized as having philosophical and technical challenges; the former can be addressed by drawing on pragmatism, the latter by considering formal mixed methods research designs proposed in a number of design typologies. There are important differences among the design typologies which provide diverse examples of designs that health psychologists can adapt for their own mixed methods research. There are also similarities; in particular, many typologies explicitly orient to the technical challenges of deciding on the respective timing of qualitative and quantitative methods and the relative emphasis placed on each method. Characteristics, strengths, and limitations of different sequential and concurrent designs are identified by reviewing five mixed methods projects each conducted for a different purpose. Adapting formal mixed methods designs can help health psychologists address the technical challenges of mixed methods research and identify the approach that best fits the research questions and purpose. This does not obfuscate the need to address philosophical challenges of mixing qualitative and quantitative methods. Statement of contribution What is already known on this subject? Mixed methods research poses philosophical and technical challenges. Pragmatism in a popular approach to the philosophical challenges while diverse typologies of mixed methods designs can help address the technical challenges. Examples of mixed methods research can be hard to locate when component studies from mixed methods projects are published separately. What does this study add? Critical reflections on the author's previously published mixed methods research illustrate how a range of different mixed methods designs can be adapted and applied to address health psychology research questions. The philosophical and technical challenges of mixed methods research should be considered together and in relation to the broader purpose of the research. © 2014 The British Psychological Society.

Profiles of Urban, Low SES, African American Girls' Attitudes toward Science: A Sequential Explanatory Mixed Methods Study

ERIC Educational Resources Information Center

Buck, Gayle; Cook, Kristin; Quigley, Cassie; Eastwood, Jennifer; Lucas, Yvonne

2009-01-01

The purpose of this study was to increase the science education community's understanding of the experiences and needs of girls who cross the traditional categorical boundaries of gender, race and socioeconomic status in a manner that has left their needs and experience largely invisible. A first of several in a series, this study sought to…

The facilitators and barriers to nurses' participation in continuing education programs: a mixed method explanatory sequential study.

PubMed

Shahhosseini, Zohreh; Hamzehgardeshi, Zeinab

2014-11-30

Since several factors affect nurses' participation in Continuing Education, and that nurses' Continuing Education affects patients' and community health status, it is essential to know facilitators and barriers of participation in Continuing Education programs and plan accordingly. This mixed approach study aimed to investigate the facilitators and barriers of nurses' participation, to explore nurses' perception of the most common facilitators and barriers. An explanatory sequential mixed methods design with follow up explanations variant were used, and it involved collecting quantitative data (361 nurses) first and then explaining the quantitative results with in-depth interviews during a qualitative study. The results showed that the mean score of facilitators to nurses' participation in Continuing Education was significantly higher than the mean score of barriers (61.99 ± 10.85 versus 51.17 ± 12.83; p<0.001, t=12.23). The highest mean score of facilitators of nurses' participation in Continuing Education was related to "Update my knowledge". By reviewing the handwritings in qualitative phase, two main levels of updating information and professional skills were extracted as the most common facilitators and lack of support as the most common barrier to nurses' participation in continuing education program. According to important role Continuing Education on professional skills, nurse managers should facilitate the nurse' participation in the Continues Education.

A mixed methods study of Canadian adolescents’ perceptions of health

PubMed Central

Pickett, William; Vandemeer, Eleanor; Taylor, Brian; Davison, Colleen

2016-01-01

Health perceptions adopted during childhood lay foundations for adult health trajectories and experiences. This study used a sequential mixed methods design to generate new evidence about child perceptions of health in two samples of Canadian children. A core qualitative study was followed by a complementary quantitative analysis to aid interpretation. Generational theory was used as a lens through which to interpret all data. Findings suggested that good health is perceived as customized and subjective. The strengths and liabilities of these perceptions are discussed, as well as implications for health promotion and prevention strategies. Through intentional consideration of the perspectives of this population group, this study makes both empirical and theoretical contributions to appreciating how cultural environments shape health perceptions. PMID:27741955

A Cultural Insight into the Development of Teacher Autonomy Support Scale: A Self-Determination Theory Perspective

ERIC Educational Resources Information Center

Awang-Hashim, Rosna; Thaliah, Rajaletchumi; Kaur, Amrita

2017-01-01

Purpose: The cross-cultural significance of autonomy within self-determination theory is divisive on universal significance. This paper aims to report a sequential exploratory mixed methods study conducted to construct and validate a scale to investigate how, in Malaysian context, the construct of autonomy is conceptualized in comparison with the…

Implementation of an Education Technology Policy in Namibia's High Schools: Through the Eyes of the Teacher

ERIC Educational Resources Information Center

Boer, Perien Joniell

2012-01-01

The purpose of this study was to explore how Namibian high school teachers experienced the ICT policy for education in their schools. This mixed methods sequential explanatory design consists of two distinct phases: quantitative followed by qualitative (Creswell & Plano Clark, 2011). Quantitative data collection involved the distribution and…

Perceptions vs Realities: How High School Principals View and Utilize Professional School Counselors

ERIC Educational Resources Information Center

Webb-Rea, Jennifer S.

2012-01-01

This mixed methods study used an explanatory sequential design to examine what principals of high schools with large low-income and racial minority student populations view as appropriate roles for the school counselors in their buildings in raising student academic achievement and how those role perceptions align with best practices and with the…

Exploring Teachers' Read-Aloud Book Selections: What Drives the Decision

ERIC Educational Resources Information Center

Ross, Rachael L.

2017-01-01

Reading aloud is a common classroom practice that has many cognitive and affective benefits for students. Early childhood teachers conduct read-aloud events in classrooms across the country on a daily basis. A read-aloud event could not occur without the intentional selection of a book. This exploratory, sequential mixed method study explored the…

The Academic Success of Homeschooled Students in a South Carolina Technical College

ERIC Educational Resources Information Center

Bagwell, Jack N., Jr.

2010-01-01

In 2010, homeschooling was increasing in prevalence in the United States. Yet, little was known about the academic achievement of these students as they matriculated into colleges and universities. The purpose of this mixed methods sequential explanatory study was to examine the academic success achieved by the homeschooled population (N = 273)…

Factors Affecting the Implementation of Sheltered Instruction Observation Protocols for English Language Learners

ERIC Educational Resources Information Center

Calderon, Carlos Trevino

2012-01-01

The purpose of this sequential mixed methods case study was to explore the role of a teacher's attitude towards Sheltered Instruction Observation Protocols (SIOP) and how those attitudes affect the program's effectiveness. SIOP is a program designed to mitigate the effects of limited English proficiency and promote equal access to the curriculum…

Exploring Group Cohesion in a Higher Education Field Experience

ERIC Educational Resources Information Center

Malcarne, Brian Keith

2012-01-01

The purpose of this study was to gain understanding into the experience of group cohesion for university students participating in an academic field experience. A mixed methods approach was used following a two-phase, sequential research design to help provide a more complete explanation of how group cohesion was impacted by the field experience.…

Development, Implementation, and Analysis of a National Survey of Faculty Goals for Undergraduate Chemistry Laboratory

ERIC Educational Resources Information Center

Bruck, Aaron D.; Towns, Marcy

2013-01-01

This work reports the development of a survey for laboratory goals in undergraduate chemistry, the analysis of reliable and valid data collected from a national survey of college chemistry faculty, and a synthesis of the findings. The study used a sequential exploratory mixed-methods design. Faculty goals for laboratory emerged across seven…

Guiding Biliteracy Development: Appropriating Cross-Linguistic and Conceptual Knowledge to Sustain Second-Language Reading Comprehension

ERIC Educational Resources Information Center

Soto Huerta, Mary Esther

2012-01-01

To examine the second-language reading development of 45 fourth-grade Latino bilinguals, a sequential mixed methods study was conducted in two phases (Creswell, 2009). The quantitative data collected in the first phase generated an index of the group's reading performance based on two grade-level assessments, a state-mandated standardized reading…

The Impact of Chess Instruction on the Critical Thinking Ability and Mathematical Achievement of Developmental Mathematics Students

ERIC Educational Resources Information Center

Berkley, Darrin K.

2012-01-01

This sequential explanatory mixed-methods study determined whether the game of chess can be used as an educational tool to improve critical thinking skills of developmental mathematics students and improve mathematics achievement for these students. Five research questions were investigated. These questions were as follows: (a) Is there a…

The Impact of Optional Flexible Year Program on Texas Assessment of Knowledge and Skills Test Scores of Fifth Grade Students

ERIC Educational Resources Information Center

Longbotham, Pamela J.

2012-01-01

The study examined the impact of participation in an optional flexible year program (OFYP) on academic achievement. The ex post facto study employed an explanatory sequential mixed methods design. The non-probability sample consisted of 163 fifth grade students in an OFYP district and 137 5th graders in a 180-day instructional year school…

Principals' Attitudes towards ICT and Their Perceptions about the Factors that Facilitate or Inhibit ICT Integration in Primary Schools of Cyprus

ERIC Educational Resources Information Center

Papaioannou, Photos; Charalambous, Kyriacos

2011-01-01

This study explores the Cyprus primary school principals' attitudes towards Information and Communication Technologies (ICT) as well as their perceptions about the factors that facilitate or inhibit ICT integration in primary schools in Cyprus. A sequential mixed method approach was used to answer the research questions that guided this study.…

Using Mixed Methods to Evaluate a Community Intervention for Sexual Assault Survivors: A Methodological Tale.

PubMed

Campbell, Rebecca; Patterson, Debra; Bybee, Deborah

2011-03-01

This article reviews current epistemological and design issues in the mixed methods literature and then examines the application of one specific design, a sequential explanatory mixed methods design, in an evaluation of a community-based intervention to improve postassault care for sexual assault survivors. Guided by a pragmatist epistemological framework, this study collected quantitative and qualitative data to understand how the implementation of a Sexual Assault Nurse Examiner (SANE) program affected prosecution rates of adult sexual assault cases in a large midwestern community. Quantitative results indicated that the program was successful in affecting legal systems change and the qualitative data revealed the mediating mechanisms of the intervention's effectiveness. Challenges of implementing this design are discussed, including epistemological and practical difficulties that developed from blending methodologies into a single project. © The Author(s) 2011.

Mining reflective continuing medical education data for family physician learning needs.

PubMed

Lewis, Denice Colleen; Pluye, Pierre; Rodriguez, Charo; Grad, Roland

2016-04-06

A mixed methods research (sequential explanatory design) studied the potential of mining the data from the consumers of continuing medical education (CME) programs, for the developers of CME programs. The quantitative data generated by family physicians, through applying the information assessment method to CME content, was presented to key informants from the CME planning community through a qualitative description study.The data were revealed to have many potential applications including supporting the creation of CME content, CME program planning and personal learning portfolios.

Preparation and evaluation of diblock copolymer-grafted silica by sequential surface initiated-atom transfer radical polymerization for reverse-phase/ion-exchange mixed-mode chromatography.

PubMed

Bo, Chun Miao; Wang, Chaozhan; Wei, Yin Mao

2017-12-01

A novel approach that involved the grafting of diblock copolymer with two types of monomer onto substrate by sequential surface initiated-atom transfer radical polymerization was proposed to prepare a mixed-mode chromatographic stationary phase. The distinguishing feature of this method is that it can be applied in the preparation of various mixed-mode stationary phases. In this study, a new reverse-phase/ion-exchange stationary phase was prepared by grafting hydrophobic styrene and cationic sodium 4-styrenesulfonate by the proposed approach onto silica surface. The chromatographic properties of the prepared stationary phase were evaluated by the separation of benzene derivatives, anilines, and β-agonists, and by the effect of pH values and acetonitrile content on the retention. Compared with typical RP columns, the prepared stationary phase achieved the better resolution and higher selectivity at a shorter separation time and lower organic content. Moreover, the application of the prepared column was proved by separating widely distributed polar and charged compounds simultaneously. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Herbage intake of dairy cows in mixed sequential grazing with breeding ewes as followers.

PubMed

Jiménez-Rosales, Juan Daniel; Améndola-Massiotti, Ricardo Daniel; Burgueño-Ferreira, Juan Andrés; Ramírez-Valverde, Rodolfo; Topete-Pelayo, Pedro; Huerta-Bravo, Maximino

2018-03-01

This study aimed to evaluate the hypothesis that mixed sequential grazing of dairy cows and breeding ewes is beneficial. During the seasons of spring-summer 2013 and autumn-winter 2013-2014, 12 (spring-summer) and 16 (autumn-winter) Holstein Friesian cows and 24 gestating (spring-summer) and lactating (autumn-winter) Pelibuey ewes grazed on six (spring-summer) and nine (autumn-winter) paddocks of alfalfa and orchard grass mixed pastures. The treatments "single species cow grazing" (CowG) and "mixed sequential grazing with ewes as followers of cows" (MixG) were evaluated, under a completely randomized design with two replicates per paddock. Herbage mass on offer (HO) and residual herbage mass (RH) were estimated by cutting samples. The estimate of herbage intake (HI) of cows was based on the use of internal and external markers; the apparent HI of ewes was calculated as the difference between HO (RH of cows) and RH. Even though HO was higher in CowG, the HI of cows was higher in MixG during spring-summer and similar in both treatments during autumn-winter, implying that in MixG the effects on the cows HI of higher alfalfa proportion and herbage accumulation rate evolving from lower residual herbage mass in the previous cycle counteracted that of a higher HO in CowG. The HI of ewes was sufficient to enable satisfactory performance as breeding ewes. Thus, the benefits of mixed sequential grazing arose from higher herbage accumulation, positive changes in botanical composition, and the achievement of sheep production without negative effects on the herbage intake of cows.

An Analysis on the Use of Educational Social Networking Sites in the Course Activities of Geography Department Students: Edmodo Sample

ERIC Educational Resources Information Center

Teyfur, Emine; Özkan, Adem; Teyfur, Mehmet

2017-01-01

The aim of this study was to examine the views of the students of Geography Department on the use of ESNS Edmodo in the course activities. Sequential explanatory design in mixed methods research designs was used in the study. This study was conducted with a total of 41 second grade students who take Europe Geography class and study in the…

The Professional Development Needs of School-Based Leadership in Preparation for a District-Wide One-to-One Initiative in a Large Urban School District

ERIC Educational Resources Information Center

Simmons, Brandon Dean

2015-01-01

The purpose of this study was to determine the professional development needs of school-based leadership in preparation for a district-wide one-to-one initiative in a large urban school district. This study used an explanatory sequential mixed methods design to answer the three research questions that drove the study. Research for this study was…

Senior Student Affairs Officers' Reports of Joint Intra-Institutional Efforts to Support College Students with Mental Illness

ERIC Educational Resources Information Center

Scheidel, Sarah

2016-01-01

The purpose of this sequential mixed-methods study was to explore senior student affairs officers' reports of joint intra-institutional efforts within the past three years to achieve the common goal of supporting the academic and personal success of college students with mental illness. The 20 factors identified by Mattessich, Murray-Close, and…

An Investigation of the Factors That Influence Preservice Teachers' Intentions and Integration of Web 2.0 Tools

ERIC Educational Resources Information Center

Sadaf, Ayesha; Newby, Timothy J.; Ertmer, Peggy A.

2016-01-01

The purpose of the study was to investigate factors that predict preservice teachers' intentions and actual uses of Web 2.0 tools in their classrooms. A two-phase, mixed method, sequential explanatory design was used. The first phase explored factors, based on the decomposed theory of planned behavior, that predict preservice teachers' intentions…

The Influence of High-Stakes Testing on Teacher Self-Efficacy and Job-Related Stress

ERIC Educational Resources Information Center

Gonzalez, Alejandro; Peters, Michelle L.; Orange, Amy; Grigsby, Bettye

2017-01-01

In the United States, teachers' job-related stress and self-efficacy levels across all grades are influenced in some manner by the demands of high-stakes testing. This sequential mixed-methods study aimed at examining the dynamics among assigned subject matter, teacher job-related stress, and teacher self-efficacy in a large south-eastern Texas…

The Impact of an Informal Science Program on Students' Science Knowledge and Interest

ERIC Educational Resources Information Center

Zandstra, Anne Maria

2012-01-01

In this sequential explanatory mixed methods study, quantitative and qualitative data were used to measure the impact of an informal science program on eleventh grade students' science knowledge and interest. The local GEAR UP project has been working for six years with a cohort of students who were in eleventh and twelfth grade during the time of…

Characterization of Mathematics Instructional Practises for Prospective Elementary Teachers with Varying Levels of Self-Efficacy in Classroom Management and Mathematics Teaching

ERIC Educational Resources Information Center

Lee, Carrie W.; Walkowiak, Temple A.; Nietfeld, John L.

2017-01-01

The purpose of this study was to investigate the relationship between prospective teachers' (PTs) instructional practises and their efficacy beliefs in classroom management and mathematics teaching. A sequential, explanatory mixed-methods design was employed. Results from efficacy surveys, implemented with 54 PTs were linked to a sample of…

The Impact of Public Prekindergarten on Social Competence and School Attendance for Hispanic Students Identified as English Language Learners

ERIC Educational Resources Information Center

Pelton, Robin R.

2017-01-01

Participation in prekindergarten for English Language Learners may positively impact social competence and decrease school absences, which may promote increased levels of academic achievement throughout the years a student is enrolled in school. The purpose of this two-phase, explanatory sequential mixed-methods study was to assess the impact of…

An Investigation of the Factors That Influence Preservice Teachers' Intentions and Actual Integration of Web 2.0 Technologies

ERIC Educational Resources Information Center

Sadaf, Ayesha

2013-01-01

The purpose of this two phase mixed methods sequential explanatory study was to investigate factors that predict preservice teachers' intentions to use Web 2.0 technologies in their future classrooms and their ability to carry out their intentions during student teaching. The first phase explored factors based on the Decomposed Theory of Planned…

The Rebel Leader: A Sequential Explanatory Mixed Methods Analysis of Rebel Superintendents in Suburban Public Schools

ERIC Educational Resources Information Center

Finch, Christopher Leigh

2013-01-01

The term rebel is virtually nonexistent in academic literature within the field of educational leadership and maintains a generally negative connotation. This research is intended to cast the term in a new light and allow for conceptualization of the word as a positive descriptor for educational leaders. This study explored the impact and efficacy…

Intervention Program for Long-Term English Learners: A Study of Long-Term English Learners' Literacy Performance in a Reading Intervention Program at Falcon School District

ERIC Educational Resources Information Center

Ayala, Erika

2016-01-01

The purpose of this sequential explanatory embedded mixed methods study was to: (a) investigate and describe the academic performance of eighth grade students in the Falcon School District (FSD) who were designated as Long Term English Learners (LTELs) and participants in FSD's reading intervention program during their fourth through eighth grade…

Development and psychometric evaluation of a women shift workers' reproductive health questionnaire: study protocol for a sequential exploratory mixed-method study.

PubMed

Nikpour, Maryam; Tirgar, Aram; Ebadi, Abbas; Ghaffari, Fatemeh; Firouzbakht, Mojgan; Hajiahmadi, Mahmod

2018-02-06

Although shift works is a certain treat for female reproductive health, but currently, there is no standardized instrument for measuring reproductive health among female shift workers. This study aims to develop and evaluate the psychometric properties of a Women Shift Workers' Reproductive Health Questionnaire (WSW-RHQ). This is a sequential exploratory mixed-method study with a qualitative and a quantitative phase. In the qualitative phase, semi-structured interviews will be held with female shift workers who live in Mazandaran Province, Iran, additionally, the literature review will be performed by searching electronic databases. Sampling will be done in different workplaces and with maximum variation respecting female shift workers' age and job and educational and different economic situation. Interview data will be analyzed using conventional content analysis and then, the primary item pool for the questionnaire will be developed. In the quantitative phase, we will evaluate the psychometric properties of the questionnaire, i.e. its face, content, construct as well as reliability via the internal consistency, stability. Finally, a scoring system will be developed for the questionnaire. The development of WSW-RHQ will facilitate the promotion and implementation of reproductive health interventions and assessment of their effectiveness. Other scholars can cross-culturally adapt and use the questionnaire according to their immediate contexts.

Modulating surface rheology by electrostatic protein/polysaccharide interactions.

PubMed

Ganzevles, Renate A; Zinoviadou, Kyriaki; van Vliet, Ton; Cohen, Martien A; de Jongh, Harmen H

2006-11-21

There is a large interest in mixed protein/polysaccharide layers at air-water and oil-water interfaces because of their ability to stabilize foams and emulsions. Mixed protein/polysaccharide adsorbed layers at air-water interfaces can be prepared either by adsorption of soluble protein/polysaccharide complexes or by sequential adsorption of complexes or polysaccharides to a previously formed protein layer. Even though the final protein and polysaccharide bulk concentrations are the same, the behavior of the adsorbed layers can be very different, depending on the method of preparation. The surface shear modulus of a sequentially formed beta-lactoglobulin/pectin layer can be up to a factor of 6 higher than that of a layer made by simultaneous adsorption. Furthermore, the surface dilatational modulus and surface shear modulus strongly (up to factors of 2 and 7, respectively) depend on the bulk -lactoglobulin/pectin mixing ratio. On the basis of the surface rheological behavior, a mechanistic understanding of how the structure of the adsorbed layers depends on the protein/polysaccharide interaction in bulk solution, mixing ratio, ionic strength, and order of adsorption to the interface (simultaneous or sequential) is derived. Insight into the effect of protein/polysaccharide interactions on the properties of adsorbed layers provides a solid basis to modulate surface rheological behavior.

When to Use What Research Design

ERIC Educational Resources Information Center

Vogt, W. Paul; Gardner, Dianne C.; Haeffele, Lynne M.

2012-01-01

Systematic, practical, and accessible, this is the first book to focus on finding the most defensible design for a particular research question. Thoughtful guidelines are provided for weighing the advantages and disadvantages of various methods, including qualitative, quantitative, and mixed methods designs. The book can be read sequentially or…

Sequential anaerobic/aerobic digestion for enhanced sludge stabilization: comparison of the process performance for mixed and waste sludge [corrected].

PubMed

Tomei, M Concetta; Carozza, Nicola Antonello

2015-05-01

Sequential anaerobic-aerobic digestion has been demonstrated as a promising alternative for enhanced sludge stabilization. In this paper, a feasibility study of the sequential digestion applied to real waste activated sludge (WAS) and mixed sludge is presented. Process performance is evaluated in terms of total solid (TS) and volatile solid (VS) removal, biogas production, and dewaterability trend in the anaerobic and double-stage digested sludge. In the proposed digestion lay out, the aerobic stage was operated with intermittent aeration to reduce the nitrogen load recycled to the wastewater treatment plant (WWTP). Experimental results showed a very good performance of the sequential digestion process for both waste and mixed sludge, even if, given its better digestibility, higher efficiencies are observed for mixed sludge. VS removal efficiencies in the anaerobic stage were 48 and 50% for waste and mixed sludge, respectively, while a significant additional improvement of the VS removal of 25% for WAS and 45% for mixed sludge has been obtained in the aerobic stage. The post-aerobic stage, operated with intermittent aeration, was also efficient in nitrogen removal, providing a significant decrease of the nitrogen content in the supernatant: nitrification efficiencies of 90 and 97% and denitrification efficiencies of 62 and 70% have been obtained for secondary and mixed sludges, respectively. A positive effect due to the aerobic stage was also observed on the sludge dewaterability in both cases. Biogas production, expressed as Nm(3)/(kgVSdestroyed), was 0.54 for waste and 0.82 for mixed sludge and is in the range of values reported in the literature in spite of the low anaerobic sludge retention time of 15 days.

Use of Elements of Theatre as Teaching Strategies to Increase Preservice Teacher Self-Efficacy and Proficiency in the Art, Science, and Business of Teaching

ERIC Educational Resources Information Center

Davidson, Maaike T.

2013-01-01

This sequential, mixed method, QUAN-QUAL study redefines the craft of teaching into the science ("what"), art ("how"), and the business of teaching to assess and prepare preservice teachers. It also measures the effectiveness of using theatrical elements as teaching strategies to effectively develop preservice teachers in the…

Assessment of Professional Development for Teachers in the Vocational Education and Training Sector: An Examination of the Concerns Based Adoption Model

ERIC Educational Resources Information Center

Saunders, Rebecca

2012-01-01

The purpose of this article is to describe the use of the Concerns Based Adoption Model (Hall & Hord, 2006) as a conceptual lens and practical methodology for professional development program assessment in the vocational education and training (VET) sector. In this sequential mixed-methods study, findings from the first two phases (two of…

Factors That Influence a Wisconsin School Board's Decision to Hire an Internal Candidate to the Superintendency

ERIC Educational Resources Information Center

Thompson, Annette VanHook

2012-01-01

This sequential mixed-methods study determined to what extent the factors identified in the literature were present in the decision to hire an internal candidate to the superintendency in Wisconsin in the last ten years. An initial survey was sent to all 424 Wisconsin public school districts and follow-up surveys sent to school board members in…

Leveling the Field Is Not Enough: Promoting Culturally Responsive Pedagogy in Teach for America through the Evaluation of Intercultural Competence, Colorblindness, White Racial Identity Attitudes, and the Belief That Culture Matters in Education

ERIC Educational Resources Information Center

Kim, Amber K.

2012-01-01

This research study examined constructs and beliefs essential to culturally responsive teachers for the purpose of understanding corps members' needs and promoting culturally responsive pedagogy (CRP) in the Colorado region of Teach for America (TFA). This study employed a transformative, sequential mixed methods design with a theoretical lens of…

Research misconduct oversight: defining case costs.

PubMed

Gammon, Elizabeth; Franzini, Luisa

2013-01-01

This study uses a sequential mixed method study design to define cost elements of research misconduct among faculty at academic medical centers. Using time driven activity based costing, the model estimates a per case cost for 17 cases of research misconduct reported by the Office of Research Integrity for the period of 2000-2005. Per case cost of research misconduct was found to range from $116,160 to $2,192,620. Research misconduct cost drivers are identified.

A Mixed-Methods Sequential Explanatory Study: Elementary Principals' Perceptions of the Impact of the Massachusetts Comprehensive Assessment System Testing Culture on the Six Conditions for Effective Learning in Schools

ERIC Educational Resources Information Center

Fraine, Patrick David

2012-01-01

There has been much debate regarding the impact of state-mandated assessment in schools. Most of the literature on this topic has been gathered from studies focused on teachers' perceptions (Hungerford, 2004). The effects, typically perceived to be negative, indicate reduced quality of teaching and learning in schools. The purpose of this study…

Safety and Immunogenicity of Sequential Rotavirus Vaccine Schedules

PubMed Central

Libster, Romina; McNeal, Monica; Walter, Emmanuel B.; Shane, Andi L.; Winokur, Patricia; Cress, Gretchen; Berry, Andrea A.; Kotloff, Karen L.; Sarpong, Kwabena; Turley, Christine B.; Harrison, Christopher J.; Pahud, Barbara A.; Marbin, Jyothi; Dunn, John; El-Khorazaty, Jill; Barrett, Jill

2016-01-01

BACKGROUND AND OBJECTIVES: Although both licensed rotavirus vaccines are safe and effective, it is often not possible to complete the schedule by using the same vaccine formulation. The goal of this study was to investigate the noninferiority of the immune responses to the 2 licensed rotavirus vaccines when administered as a mixed schedule compared with administering a single vaccine formulation alone. METHODS: Randomized, multicenter, open-label study. Healthy infants (6–14 weeks of age) were randomized to receive rotavirus vaccines in 1 of 5 different schedules (2 using a single vaccine for all doses, and 3 using mixed schedules). The group receiving only the monovalent rotavirus vaccine received 2 doses of vaccine and the other 4 groups received 3 doses of vaccine. Serum for immunogenicity testing was obtained 1 month after the last vaccine dose and the proportion of seropositive children (rotavirus immunoglobulin A ≥20 U/mL) were compared in all the vaccine groups. RESULTS: Between March 2011 and September 2013, 1393 children were enrolled and randomized. Immune responses to all the sequential mixed vaccine schedules were shown to be noninferior when compared with the 2 single vaccine reference groups. The proportion of children seropositive to at least 1 vaccine antigen at 1 month after vaccination ranged from 77% to 96%, and was not significantly different among all the study groups. All schedules were well tolerated. CONCLUSIONS: Mixed schedules are safe and induced comparable immune responses when compared with the licensed rotavirus vaccines given alone. PMID:26823540

Alternative perspectives of safety in home delivered health care: a sequential exploratory mixed method study.

PubMed

Jones, Sarahjane

2016-10-01

The aim of this study was to discover and describe how patients, carers and case management nurses define safety and compare it to the traditional risk reduction and harm avoidance definition of safety. Care services are increasingly being delivered in the home for patients with complex long-term conditions. However, the concept of safety remains largely unexplored. A sequential, exploratory mixed method design. A qualitative case study of the UK National Health Service case management programme in the English UK National Health Service was deployed during 2012. Thirteen interviews were conducted with patients (n = 9) and carers (n = 6) and three focus groups with nurses (n = 17) from three community care providers. The qualitative element explored the definition of safety. Data were subjected to framework analysis and themes were identified by participant group. Sequentially, a cross-sectional survey was conducted during 2013 in a fourth community care provider (patient n = 35, carer n = 19, nurse n = 26) as a form of triangulation. Patients and carers describe safety differently to case management nurses, choosing to focus on meeting needs. They use more positive language and recognize the role they have in safety in home-delivered health care. In comparison, case management nurses described safety similarly to the definitions found in the literature. However, when offered the patient and carer definition of safety, they preferentially selected this definition to their own or the literature definition. Patients and carers offer an alternative perspective on patient safety in home-delivered health care that identifies their role in ensuring safety and is more closely aligned with the empowerment philosophy of case management. © 2016 John Wiley & Sons Ltd.

Attitudes, Interests, and Perceived Self-Efficacy toward Science of Middle School Minority Female Students: Considerations for Their Low Achievement and Participation in STEM Disciplines

ERIC Educational Resources Information Center

Dowey, Ana Lucrecia

2013-01-01

The under participation of minority females in STEM fields has been a chronic problem in the United States, mainly when it is analyzed through the lens of their relative representation in the population. The results of the first or quantitative phase, of this two phase sequential, mixed method study, revealed academic achievement or performance in…

Measuring Teacher Immediacy and Communication Competence on Student Achievement in Calculus: A Sequential Explanatory Mixed Method Design

ERIC Educational Resources Information Center

Barclay, Allen C.

2012-01-01

On a national level, data indicate that about 40 percent of students in calculus courses finish with a grade of D or F, drop the course, or withdraw (Reinholz, 2009). This high failure rate has led to research studies investigating the teaching of calculus at the national level (House, 1995). Calculus courses have a history of high failure rates,…

Alcohol Consumption Decisions among Nonabusing Drinkers Diagnosed with Hepatitis C: An Exploratory Sequential Mixed Methods Study

PubMed Central

Stoller, Eleanor Palo; Webster, Noah J.; Blixen, Carol E.; McCormick, Richard A.; Hund, Andrew J.; Perzynski, Adam T.; Kanuch, Stephanie W.; Thomas, Charles L.; Kercher, Kyle; Dawson, Neal V.

2009-01-01

Most studies of decisions to curtail alcohol consumption reflect experiences of abusing drinkers. We employ an exploratory sequential research design to explore the applicability of this research to the experience of nonabusing drinkers advised to curtail alcohol consumption after a Hepatitis C diagnosis. A qualitative component identified 17 new decision factors not reflected in an inventory of factors based on synthesis of existing scales. We triangulated qualitative data by supplementing semi-structured interviews with Internet postings. A quantitative component estimated prevalence and association with current drinking of these new decision factors. Patients who quit drinking tended to attribute post-diagnosis drinking to occasional triggers, whereas patients who were still drinking were more likely to endorse rationales not tied to specific triggers. PMID:20046861

Preference-based disease-specific health-related quality of life instrument for glaucoma: a mixed methods study protocol

PubMed Central

Muratov, Sergei; Podbielski, Dominik W; Jack, Susan M; Ahmed, Iqbal Ike K; Mitchell, Levine A H; Baltaziak, Monika; Xie, Feng

2016-01-01

Introduction A primary objective of healthcare services is to improve patients' health and health-related quality of life (HRQoL). Glaucoma, which affects a substantial proportion of the world population, has a significant detrimental impact on HRQoL. Although there are a number of glaucoma-specific questionnaires to measure HRQoL, none is preference-based which prevent them from being used in health economic evaluation. The proposed study is aimed to develop a preference-based instrument that is capable of capturing important effects specific to glaucoma and treatments on HRQoL and is scored based on the patients' preferences. Methods A sequential, exploratory mixed methods design will be used to guide the development and evaluation of the HRQoL instrument. The study consists of several stages to be implemented sequentially: item identification, item selection, validation and valuation. The instrument items will be identified and selected through a literature review and the conduct of a qualitative study. Validation will be conducted to establish psychometric properties of the instrument followed by a valuation exercise to derive utility scores for the health states described. Ethics and dissemination This study has been approved by the Trillium Health Partners Research Ethics Board (ID number 753). All personal information will be de-identified with the identification code kept in a secured location including the rest of the study data. Only qualified and study-related personnel will be allowed to access the data. The results of the study will be distributed widely through peer-reviewed journals, conferences and internal meetings. PMID:28186941

Privatization and subsidization in a leadership duopoly

NASA Astrophysics Data System (ADS)

Ferreira, Fernanda A.

2017-07-01

In this paper, we consider a competition in both mixed and privatized markets, in which the firms set prices in a sequential way. We study the effects of optimal production subsidies in both mixed and privatized duopoly.

Computational aspects of helicopter trim analysis and damping levels from Floquet theory

NASA Technical Reports Server (NTRS)

Gaonkar, Gopal H.; Achar, N. S.

1992-01-01

Helicopter trim settings of periodic initial state and control inputs are investigated for convergence of Newton iteration in computing the settings sequentially and in parallel. The trim analysis uses a shooting method and a weak version of two temporal finite element methods with displacement formulation and with mixed formulation of displacements and momenta. These three methods broadly represent two main approaches of trim analysis: adaptation of initial-value and finite element boundary-value codes to periodic boundary conditions, particularly for unstable and marginally stable systems. In each method, both the sequential and in-parallel schemes are used and the resulting nonlinear algebraic equations are solved by damped Newton iteration with an optimally selected damping parameter. The impact of damped Newton iteration, including earlier-observed divergence problems in trim analysis, is demonstrated by the maximum condition number of the Jacobian matrices of the iterative scheme and by virtual elimination of divergence. The advantages of the in-parallel scheme over the conventional sequential scheme are also demonstrated.

The early identification of risk factors on the pathway to school dropout in the SIODO study: a sequential mixed-methods study.

PubMed

Theunissen, Marie-José; Griensven van, Ilse; Verdonk, Petra; Feron, Frans; Bosma, Hans

2012-11-27

School dropout is a persisting problem with major socioeconomic consequences. Although poor health probably contributes to pathways leading to school dropout and health is likely negatively affected by dropout, these issues are relatively absent on the public health agenda. This emphasises the importance of integrative research aimed at identifying children at risk for school dropout at an early stage, discovering how socioeconomic status and gender affect health-related pathways that lead to dropout and developing a prevention tool that can be used in public health services for youth. The SIODO study is a sequential mixed-methods study. A case-control study will be conducted among 18 to 24 year olds in the south of the Netherlands (n = 580). Data are currently being collected from compulsory education departments at municipalities (dropout data), regional public health services (developmental data from birth onwards) and an additional questionnaire has been sent to participants (e.g. personality data). Advanced analyses, including cluster and factor analyses, will be used to identify children at risk at an early stage. Using the quantitative data, we have planned individual interviews with participants and focus groups with important stakeholders such as parents, teachers and public health professionals. A thematic content analysis will be used to analyse the qualitative data. The SIODO study will use a life-course perspective, the ICF-CY model to group the determinants and a mixed-methods design. In this respect, the SIODO study is innovative because it both broadens and deepens the study of health-related determinants of school dropout. It examines how these determinants contribute to socioeconomic and gender differences in health and contributes to the development of a tool that can be used in public health practice to tackle the problem of school dropout at its roots.

Translating Basic Behavioral and Social Science Research to Clinical Application: The EVOLVE Mixed Methods Approach

PubMed Central

Peterson, Janey C.; Czajkowski, Susan; Charlson, Mary E.; Link, Alissa R.; Wells, Martin T.; Isen, Alice M.; Mancuso, Carol A.; Allegrante, John P.; Boutin-Foster, Carla; Ogedegbe, Gbenga; Jobe, Jared B.

2012-01-01

Objective To describe a mixed-methods approach to develop and test a basic behavioral science-informed intervention to motivate behavior change in three high-risk clinical populations. Our theoretically-derived intervention comprised a combination of positive affect and self-affirmation (PA/SA) which we applied to three clinical chronic disease populations. Methods We employed a sequential mixed methods model (EVOLVE) to design and test the PA/SA intervention in order to increase physical activity in people with coronary artery disease (post-percutaneous coronary intervention [PCI]) or asthma (ASM), and to improve medication adherence in African Americans with hypertension (HTN). In an initial qualitative phase, we explored participant values and beliefs. We next pilot tested and refined the intervention, and then conducted three randomized controlled trials (RCTs) with parallel study design. Participants were randomized to combined PA/SA vs. an informational control (IC) and followed bimonthly for 12 months, assessing for health behaviors and interval medical events. Results Over 4.5 years, we enrolled 1,056 participants. Changes were sequentially made to the intervention during the qualitative and pilot phases. The three RCTs enrolled 242 PCI, 258 ASM and 256 HTN participants (n=756). Overall, 45.1% of PA/SA participants versus 33.6% of IC participants achieved successful behavior change (p=0.001). In multivariate analysis PA/SA intervention remained a significant predictor of achieving behavior change (p<0.002, OR=1.66, 95% CI 1.22–2.27), controlling for baseline negative affect, comorbidity, gender, race/ethnicity, medical events, smoking and age. Conclusions The EVOLVE method is a means by which basic behavioral science research can be translated into efficacious interventions for chronic disease populations. PMID:22963594

An Investigation into the Socio-Psychological Determinants of Farmers' Conservation Decisions: Method and Implications for Policy, Extension and Research

ERIC Educational Resources Information Center

Wauters, E.; Mathijs, E.

2013-01-01

Purpose: The aim of this article is to present and apply a method to investigate farmers' socio-psychological determinants of conservation practice adoption, as an aid in extension, policy and conservation practice design. Design/methodology/approach: We use a sequential mixed method, starting with qualitative semi-structured interviews (n = 24),…

Exploring selection and recruitment processes for newly qualified nurses: a sequential-explanatory mixed-method study.

PubMed

Newton, Paul; Chandler, Val; Morris-Thomson, Trish; Sayer, Jane; Burke, Linda

2015-01-01

To map current selection and recruitment processes for newly qualified nurses and to explore the advantages and limitations of current selection and recruitment processes. The need to improve current selection and recruitment practices for newly qualified nurses is highlighted in health policy internationally. A cross-sectional, sequential-explanatory mixed-method design with 4 components: (1) Literature review of selection and recruitment of newly qualified nurses; and (2) Literature review of a public sector professions' selection and recruitment processes; (3) Survey mapping existing selection and recruitment processes for newly qualified nurses; and (4) Qualitative study about recruiters' selection and recruitment processes. Literature searches on the selection and recruitment of newly qualified candidates in teaching and nursing (2005-2013) were conducted. Cross-sectional, mixed-method data were collected from thirty-one (n = 31) individuals in health providers in London who had responsibility for the selection and recruitment of newly qualified nurses using a survey instrument. Of these providers who took part, six (n = 6) purposively selected to be interviewed qualitatively. Issues of supply and demand in the workforce, rather than selection and recruitment tools, predominated in the literature reviews. Examples of tools to measure values, attitudes and skills were found in the nursing literature. The mapping exercise found that providers used many selection and recruitment tools, some providers combined tools to streamline process and assure quality of candidates. Most providers had processes which addressed the issue of quality in the selection and recruitment of newly qualified nurses. The 'assessment centre model', which providers were adopting, allowed for multiple levels of assessment and streamlined recruitment. There is a need to validate the efficacy of the selection tools. © 2014 John Wiley & Sons Ltd.

An Evaluation of Physician-to-Patient Communication Training in Medical Schools across the United States: A Status Report on the Nation's Efforts to Promote Health Literacy by Adding Health Literacy Courses to Medical School Curriculum

ERIC Educational Resources Information Center

Frazier, Andrea P.

2012-01-01

This research study employed a mixed method sequential approach and investigated the number of Schools of Medicine within the United States that offer health literacy as a component of their curriculum and a course of study within the academic setting. Data were gathered from medical school surveys and personal interviews. Curriculum content,…

Analyzing Gender Differences in Black Faculty Marginalization through a Sequential Mixed-Methods Design

ERIC Educational Resources Information Center

Griffin, Kimberly A.; Bennett, Jessica C.; Harris, Jessica

2011-01-01

In this article, the authors demonstrate how researchers can integrate qualitative and quantitative methods to gain a deeper understanding of the prevalence and nature of cultural taxation among black professors. In doing so, they show how the impact of cultural taxation on the experiences of black faculty in the academy is best captured using…

Translating basic behavioral and social science research to clinical application: the EVOLVE mixed methods approach.

PubMed

Peterson, Janey C; Czajkowski, Susan; Charlson, Mary E; Link, Alissa R; Wells, Martin T; Isen, Alice M; Mancuso, Carol A; Allegrante, John P; Boutin-Foster, Carla; Ogedegbe, Gbenga; Jobe, Jared B

2013-04-01

To describe a mixed-methods approach to develop and test a basic behavioral science-informed intervention to motivate behavior change in 3 high-risk clinical populations. Our theoretically derived intervention comprised a combination of positive affect and self-affirmation (PA/SA), which we applied to 3 clinical chronic disease populations. We employed a sequential mixed methods model (EVOLVE) to design and test the PA/SA intervention in order to increase physical activity in people with coronary artery disease (post-percutaneous coronary intervention [PCI]) or asthma (ASM) and to improve medication adherence in African Americans with hypertension (HTN). In an initial qualitative phase, we explored participant values and beliefs. We next pilot tested and refined the intervention and then conducted 3 randomized controlled trials with parallel study design. Participants were randomized to combined PA/SA versus an informational control and were followed bimonthly for 12 months, assessing for health behaviors and interval medical events. Over 4.5 years, we enrolled 1,056 participants. Changes were sequentially made to the intervention during the qualitative and pilot phases. The 3 randomized controlled trials enrolled 242 participants who had undergone PCI, 258 with ASM, and 256 with HTN (n = 756). Overall, 45.1% of PA/SA participants versus 33.6% of informational control participants achieved successful behavior change (p = .001). In multivariate analysis, PA/SA intervention remained a significant predictor of achieving behavior change (p < .002, odds ratio = 1.66), 95% CI [1.22, 2.27], controlling for baseline negative affect, comorbidity, gender, race/ethnicity, medical events, smoking, and age. The EVOLVE method is a means by which basic behavioral science research can be translated into efficacious interventions for chronic disease populations.

Doctoral Students' Perceived Barriers That Slow the Progress toward Completing a Doctoral Dissertation: A Mixed Analysis

ERIC Educational Resources Information Center

Hwang, Eunjin; Smith, Rachel N.; Byers, Valerie Tharp; Dickerson, Shirley; McAlister-Shields, Leah; Onwuegbuzie, Anthony J.; Benge, Cindy

2015-01-01

The non-completion of doctoral degrees has been a concern due to its economic, social, and personal consequences. In the current study, the researchers investigated perceived barriers of select doctoral students in completing their doctoral degrees by utilizing a fully mixed sequential mixed research design. The quantitative and qualitative data…

Mixed Emotions and Coping: The Benefits of Secondary Emotions

PubMed Central

Braniecka, Anna; Trzebińska, Ewa; Dowgiert, Aneta; Wytykowska, Agata

2014-01-01

The existing empirical literature suggests that during difficult situations, the concurrent experience of positive and negative affects may be ideal for ensuring successful adaptation and well-being. However, different patterns of mixed emotions may have different adaptive consequences. The present research tested the proposition that experiencing a pattern of secondary mixed emotion (i.e., secondary emotion that embrace both positive and negative affects) more greatly promotes adaptive coping than experiencing two other patterns of mixed emotional experiences: simultaneous (i.e., two emotions of opposing affects taking place at the same time) and sequential (i.e., two emotions of opposing affects switching back and forth). Support for this hypothesis was obtained from two experiments (Studies 1 and 2) and a longitudinal survey (Study 3). The results revealed that secondary mixed emotions predominate over sequential and simultaneous mixed emotional experiences in promoting adaptive coping through fostering the motivational and informative functions of emotions; this is done by providing solution-oriented actions rather than avoidance, faster decisions regarding coping strategies (Study 1), easier access to self-knowledge, and better narrative organization (Study 2). Furthermore, individuals characterized as being prone to feeling secondary mixed emotions were more resilient to stress caused by transitions than those who were characterized as being prone to feeling opposing emotions separately (Study 3). Taken together, the preliminary results indicate that the pattern of secondary mixed emotion provides individuals with a higher capacity to handle adversity than the other two patterns of mixed emotional experience. PMID:25084461

Mixed emotions and coping: the benefits of secondary emotions.

PubMed

Braniecka, Anna; Trzebińska, Ewa; Dowgiert, Aneta; Wytykowska, Agata

2014-01-01

The existing empirical literature suggests that during difficult situations, the concurrent experience of positive and negative affects may be ideal for ensuring successful adaptation and well-being. However, different patterns of mixed emotions may have different adaptive consequences. The present research tested the proposition that experiencing a pattern of secondary mixed emotion (i.e., secondary emotion that embrace both positive and negative affects) more greatly promotes adaptive coping than experiencing two other patterns of mixed emotional experiences: simultaneous (i.e., two emotions of opposing affects taking place at the same time) and sequential (i.e., two emotions of opposing affects switching back and forth). Support for this hypothesis was obtained from two experiments (Studies 1 and 2) and a longitudinal survey (Study 3). The results revealed that secondary mixed emotions predominate over sequential and simultaneous mixed emotional experiences in promoting adaptive coping through fostering the motivational and informative functions of emotions; this is done by providing solution-oriented actions rather than avoidance, faster decisions regarding coping strategies (Study 1), easier access to self-knowledge, and better narrative organization (Study 2). Furthermore, individuals characterized as being prone to feeling secondary mixed emotions were more resilient to stress caused by transitions than those who were characterized as being prone to feeling opposing emotions separately (Study 3). Taken together, the preliminary results indicate that the pattern of secondary mixed emotion provides individuals with a higher capacity to handle adversity than the other two patterns of mixed emotional experience.

Simultaneous injection-effective mixing analysis of palladium.

PubMed

Teshima, Norio; Noguchi, Daisuke; Joichi, Yasutaka; Lenghor, Narong; Ohno, Noriko; Sakai, Tadao; Motomizu, Shoji

2010-01-01

A novel concept of simultaneous injection-effective mixing analysis (SIEMA) is proposed, and a SIEMA method applied to the spectrophotometric determination of palladium using a water-soluble chromogenic reagent has been demonstrated. The flow configuration of SIEMA is a hybrid format of flow injection analysis (FIA), sequential injection analysis (SIA) and multicommutation in flow-based analysis. Sample and reagent solutions are aspirated into each holding coil through each solenoid valve by a syringe pump, and then the zones are simultaneously dispensed (injected) into a mixing coil by reversed flow toward a detector through a confluence point. This results in effective mixing and rapid detection with low reagent consumption.

Parent Perceptions and Observations of Their Children with Autism Age 14-to-26 Concerning Generalization of Daily Living Skills at Home and in the Community

ERIC Educational Resources Information Center

Crosby, Patrick H.

2009-01-01

The purpose of this sequential mixed methods study was to determine if students with autism from 19-to-26 years of age who receive instruction in Daily Living Skills (DLS) class sustain, improve, or decline in their ability to generalize DLS at home and in the community. Research regarding how well students with autism from 19-to-26 years of age…

Iodine speciation in coastal and inland bathing waters and seaweeds extracts using a sequential injection standard addition flow-batch method.

PubMed

Santos, Inês C; Mesquita, Raquel B R; Bordalo, Adriano A; Rangel, António O S S

2015-02-01

The present work describes the development of a sequential injection standard addition method for iodine speciation in bathing waters and seaweeds extracts without prior sample treatment. Iodine speciation was obtained by assessing the iodide and iodate content, the two inorganic forms of iodine in waters. For the determination of iodide, an iodide ion selective electrode (ISE) was used. The indirect determination of iodate was based on the spectrophotometric determination of nitrite (Griess reaction). For the iodate measurement, a mixing chamber was employed (flow batch approach) to explore the inherent efficient mixing, essential for the indirect determination of iodate. The application of the standard addition method enabled detection limits of 0.14 µM for iodide and 0.02 µM for iodate, together with the direct introduction of the target water samples, coastal and inland bathing waters. The results obtained were in agreement with those obtained by ICP-MS and a colorimetric reference procedure. Recovery tests also confirmed the accuracy of the developed method which was effectively applied to bathing waters and seaweed extracts. Copyright © 2014 Elsevier B.V. All rights reserved.

Examining Informal Learning in Commercial Airline Pilots' Communities of Practice

ERIC Educational Resources Information Center

Corns, Kevin M.

2014-01-01

A pragmatic sequential mixed methods research methodology was used to examine commercial airline pilots' (N =156) types and frequencies of informal learning activities, perceptions of workplace informal learning, and opinions on how organizations should support workplace informal learning outside of the formal learning environment. This study…

Simultaneous acquisition of 2D and 3D solid-state NMR experiments for sequential assignment of oriented membrane protein samples.

PubMed

Gopinath, T; Mote, Kaustubh R; Veglia, Gianluigi

2015-05-01

We present a new method called DAISY (Dual Acquisition orIented ssNMR spectroScopY) for the simultaneous acquisition of 2D and 3D oriented solid-state NMR experiments for membrane proteins reconstituted in mechanically or magnetically aligned lipid bilayers. DAISY utilizes dual acquisition of sine and cosine dipolar or chemical shift coherences and long living (15)N longitudinal polarization to obtain two multi-dimensional spectra, simultaneously. In these new experiments, the first acquisition gives the polarization inversion spin exchange at the magic angle (PISEMA) or heteronuclear correlation (HETCOR) spectra, the second acquisition gives PISEMA-mixing or HETCOR-mixing spectra, where the mixing element enables inter-residue correlations through (15)N-(15)N homonuclear polarization transfer. The analysis of the two 2D spectra (first and second acquisitions) enables one to distinguish (15)N-(15)N inter-residue correlations for sequential assignment of membrane proteins. DAISY can be implemented in 3D experiments that include the polarization inversion spin exchange at magic angle via I spin coherence (PISEMAI) sequence, as we show for the simultaneous acquisition of 3D PISEMAI-HETCOR and 3D PISEMAI-HETCOR-mixing experiments.

To Build a Better (Digital) Mousetrap: Testing the Learning Effectiveness of Al Gore's Book "Our Choice" against the iPad App Based on the Book in Order to Suggest Design Improvements for Future Enriched Ebooks

ERIC Educational Resources Information Center

Halliday, Steven W.

2012-01-01

This sequential explanatory mixed methods study tested the learning effectiveness of a codex book against a convergent media resource based on the same content. It also investigated whether users of the two formats reported any differences in their liking of the two formats, or in their tendency to be persuaded to the degree that they altered…

Modelling, fabrication and characterization of a polymeric micromixer based on sequential segmentation.

PubMed

Nguyen, Nam-Trung; Huang, Xiaoyang

2006-06-01

Effective and fast mixing is important for many microfluidic applications. In many cases, mixing is limited by molecular diffusion due to constrains of the laminar flow in the microscale regime. According to scaling law, decreasing the mixing path can shorten the mixing time and enhance mixing quality. One of the techniques for reducing mixing path is sequential segmentation. This technique divides solvent and solute into segments in axial direction. The so-called Taylor-Aris dispersion can improve axial transport by three orders of magnitudes. The mixing path can be controlled by the switching frequency and the mean velocity of the flow. Mixing ratio can be controlled by pulse width modulation of the switching signal. This paper first presents a simple time-dependent one-dimensional analytical model for sequential segmentation. The model considers an arbitrary mixing ratio between solute and solvent as well as the axial Taylor-Aris dispersion. Next, a micromixer was designed and fabricated based on polymeric micromachining. The micromixer was formed by laminating four polymer layers. The layers are micro machined by a CO(2) laser. Switching of the fluid flows was realized by two piezoelectric valves. Mixing experiments were evaluated optically. The concentration profile along the mixing channel agrees qualitatively well with the analytical model. Furthermore, mixing results at different switching frequencies were investigated. Due to the dynamic behavior of the valves and the fluidic system, mixing quality decreases with increasing switching frequency.

Understanding What Is Possible across a Career: Professional Identity Development beyond Transition to Teaching

ERIC Educational Resources Information Center

Mahmoudi-Gahrouei, Vahid; Tavakoli, Mansoor; Hamman, Doug

2016-01-01

Professional identity surfaces repeatedly as an important underlying factor in teacher development. A sequential explanatory mixed methods design was used to investigate identity development in terms of teachers' expected and feared possible selves. Teachers (n = 120) representing three career groups (prospect, new, and experienced) participated.…

Critical Reading Skills and Translation Ability of Thai EFL Students: Pragmatic, Syntactic, and Semantic Aspects

ERIC Educational Resources Information Center

Sriwantaneeyakul, Suttawan

2018-01-01

Translation ability requires many language skills to produce an accurate and complete text; however, one important skill, critical reading in the research, has been neglected. This research, therefore, employed the explanatory sequential mixed method to investigate the differences in Thai-English translation ability between students with a high…

Identification of DNA-Binding Proteins Using Mixed Feature Representation Methods.

PubMed

Qu, Kaiyang; Han, Ke; Wu, Song; Wang, Guohua; Wei, Leyi

2017-09-22

DNA-binding proteins play vital roles in cellular processes, such as DNA packaging, replication, transcription, regulation, and other DNA-associated activities. The current main prediction method is based on machine learning, and its accuracy mainly depends on the features extraction method. Therefore, using an efficient feature representation method is important to enhance the classification accuracy. However, existing feature representation methods cannot efficiently distinguish DNA-binding proteins from non-DNA-binding proteins. In this paper, a multi-feature representation method, which combines three feature representation methods, namely, K-Skip-N-Grams, Information theory, and Sequential and structural features (SSF), is used to represent the protein sequences and improve feature representation ability. In addition, the classifier is a support vector machine. The mixed-feature representation method is evaluated using 10-fold cross-validation and a test set. Feature vectors, which are obtained from a combination of three feature extractions, show the best performance in 10-fold cross-validation both under non-dimensional reduction and dimensional reduction by max-relevance-max-distance. Moreover, the reduced mixed feature method performs better than the non-reduced mixed feature technique. The feature vectors, which are a combination of SSF and K-Skip-N-Grams, show the best performance in the test set. Among these methods, mixed features exhibit superiority over the single features.

Modeling sustainability in renewable energy supply chain systems

NASA Astrophysics Data System (ADS)

Xie, Fei

This dissertation aims at modeling sustainability of renewable fuel supply chain systems against emerging challenges. In particular, the dissertation focuses on the biofuel supply chain system design, and manages to develop advanced modeling framework and corresponding solution methods in tackling challenges in sustaining biofuel supply chain systems. These challenges include: (1) to integrate "environmental thinking" into the long-term biofuel supply chain planning; (2) to adopt multimodal transportation to mitigate seasonality in biofuel supply chain operations; (3) to provide strategies in hedging against uncertainty from conversion technology; and (4) to develop methodologies in long-term sequential planning of the biofuel supply chain under uncertainties. All models are mixed integer programs, which also involves multi-objective programming method and two-stage/multistage stochastic programming methods. In particular for the long-term sequential planning under uncertainties, to reduce the computational challenges due to the exponential expansion of the scenario tree, I also developed efficient ND-Max method which is more efficient than CPLEX and Nested Decomposition method. Through result analysis of four independent studies, it is found that the proposed modeling frameworks can effectively improve the economic performance, enhance environmental benefits and reduce risks due to systems uncertainties for the biofuel supply chain systems.

Preference-based disease-specific health-related quality of life instrument for glaucoma: a mixed methods study protocol.

PubMed

Muratov, Sergei; Podbielski, Dominik W; Jack, Susan M; Ahmed, Iqbal Ike K; Mitchell, Levine A H; Baltaziak, Monika; Xie, Feng

2016-11-08

A primary objective of healthcare services is to improve patients' health and health-related quality of life (HRQoL). Glaucoma, which affects a substantial proportion of the world population, has a significant detrimental impact on HRQoL. Although there are a number of glaucoma-specific questionnaires to measure HRQoL, none is preference-based which prevent them from being used in health economic evaluation. The proposed study is aimed to develop a preference-based instrument that is capable of capturing important effects specific to glaucoma and treatments on HRQoL and is scored based on the patients' preferences. A sequential, exploratory mixed methods design will be used to guide the development and evaluation of the HRQoL instrument. The study consists of several stages to be implemented sequentially: item identification, item selection, validation and valuation. The instrument items will be identified and selected through a literature review and the conduct of a qualitative study. Validation will be conducted to establish psychometric properties of the instrument followed by a valuation exercise to derive utility scores for the health states described. This study has been approved by the Trillium Health Partners Research Ethics Board (ID number 753). All personal information will be de-identified with the identification code kept in a secured location including the rest of the study data. Only qualified and study-related personnel will be allowed to access the data. The results of the study will be distributed widely through peer-reviewed journals, conferences and internal meetings. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

On-orbit servicing system assessment and optimization methods based on lifecycle simulation under mixed aleatory and epistemic uncertainties

NASA Astrophysics Data System (ADS)

Yao, Wen; Chen, Xiaoqian; Huang, Yiyong; van Tooren, Michel

2013-06-01

To assess the on-orbit servicing (OOS) paradigm and optimize its utilities by taking advantage of its inherent flexibility and responsiveness, the OOS system assessment and optimization methods based on lifecycle simulation under uncertainties are studied. The uncertainty sources considered in this paper include both the aleatory (random launch/OOS operation failure and on-orbit component failure) and the epistemic (the unknown trend of the end-used market price) types. Firstly, the lifecycle simulation under uncertainties is discussed. The chronological flowchart is presented. The cost and benefit models are established, and the uncertainties thereof are modeled. The dynamic programming method to make optimal decision in face of the uncertain events is introduced. Secondly, the method to analyze the propagation effects of the uncertainties on the OOS utilities is studied. With combined probability and evidence theory, a Monte Carlo lifecycle Simulation based Unified Uncertainty Analysis (MCS-UUA) approach is proposed, based on which the OOS utility assessment tool under mixed uncertainties is developed. Thirdly, to further optimize the OOS system under mixed uncertainties, the reliability-based optimization (RBO) method is studied. To alleviate the computational burden of the traditional RBO method which involves nested optimum search and uncertainty analysis, the framework of Sequential Optimization and Mixed Uncertainty Analysis (SOMUA) is employed to integrate MCS-UUA, and the RBO algorithm SOMUA-MCS is developed. Fourthly, a case study on the OOS system for a hypothetical GEO commercial communication satellite is investigated with the proposed assessment tool. Furthermore, the OOS system is optimized with SOMUA-MCS. Lastly, some conclusions are given and future research prospects are highlighted.

Collaboration amongst clinical nursing leadership teams: a mixed-methods sequential explanatory study.

PubMed

Lamont, Scott; Brunero, Scott; Lyons, Sarah; Foster, Karlie; Perry, Lin

2015-11-01

To explore intra-professional collaboration amongst nursing leadership teams at a tertiary referral hospital in Sydney. Effective working within a wide network of alliances is critical to patient outcomes. An understanding of collaboration amongst nursing leadership teams is essential within this context. A sequential explanatory mixed-methods design was used. The Collaborative Behaviour scale was sent to 106 Nurse Unit Managers, Nurse Educators and Clinical Nurse Consultants to measure pairwise collaborative behaviours; two follow-up focus groups with 15 participants were conducted. Data were collected between May 2012 and May 2013. A thematic analysis of focus group data provided a detailed explanation of the questionnaire findings. The findings identified high collaboration between dyad groups. Two themes emerged from the thematic analysis: (1) professional role and expectations; with sub-themes of transparency and clarity of individual roles; and intra/interpersonal aspects of role functioning; and (2) organisational infrastructure and governance. These leadership teams can be effective and powerful vehicles for change and are central to optimum patient outcomes. Organisational strategic planning and evaluation can benefit from understanding how to promote collaborative behaviours in these nurse leaders. To date, little research has explored collaboration amongst nursing leadership teams. Successful collaboration may contribute to the efficient use of nursing resources; improve patient outcomes, and ultimately, nurse satisfaction and retention. © 2014 John Wiley & Sons Ltd.

The Effects of a Collaborative Problem-Based Learning Experience on Students' Motivation in Engineering Capstone Courses

ERIC Educational Resources Information Center

Jones, Brett D.; Epler, Cory M.; Mokri, Parastou; Bryant, Lauren H.; Paretti, Marie C.

2013-01-01

We identified and examined how the instructional elements of problem-based learning capstone engineering courses affected students' motivation to engage in the courses. We employed a two-phase, sequential, explanatory, mixed methods research design. For the quantitative phase, 47 undergraduate students at a large public university completed a…

Factors Affecting the Retention of First-Career and Second-Career Science Teachers in Urban High Schools

ERIC Educational Resources Information Center

Rak, Rosemary C.

2013-01-01

The turnover of high school science teachers is an especially troubling problem in urban schools with economically disadvantaged students. Because high teacher turnover rates impede effective instruction, the persistence of teacher attrition is a serious concern. Using an online survey and interviews in a sequential mixed-methods approach, this…

How Do Parents Acquire Information to Support Their Child with a Disability and Navigate Individualised Funding Schemes?

ERIC Educational Resources Information Center

Tracey, Danielle; Johnston, Christine; Papps, Fiona Ann; Mahmic, Sylvana

2018-01-01

With the international trend towards individualised funding packages that allocate funds to individuals to spend on disability support needs, the challenge of ensuring parents can readily access useful information to make decisions becomes paramount. The present research used a two stage, mixed method sequential approach (with 291 parents surveyed…

Method and system for controlled combustion engines

DOEpatents

Oppenheim, A. K.

1990-01-01

A system for controlling combustion in internal combustion engines of both the Diesel or Otto type, which relies on establishing fluid dynamic conditions and structures wherein fuel and air are entrained, mixed and caused to be ignited in the interior of a multiplicity of eddies, and where these structures are caused to sequentially fill the headspace of the cylinders.

A Mixed Methods Investigation of Caregiver Coaching in an Early Intervention Model: Differences in Providers for Children with Hearing Loss

ERIC Educational Resources Information Center

King, Alison R.

2017-01-01

The purpose of this research is to investigate the relationship between early intervention providers' backgrounds, and their perceptions of caregiver coaching and auditory skill development, to develop professional development programs. An explanatory sequential design was used with participants of varying backgrounds and experience. In the first…

Highly Structured ePortfolio Platform for Bachelor of Nursing Students: Lessons Learned in Implementation

ERIC Educational Resources Information Center

Collins, Emma; O'Brien, Ray

2018-01-01

In 2015, the School of Nursing at Otago Polytechnic, a tertiary institution in Dunedin, New Zealand commenced using an ePortfolio platform with students in the Bachelor of Nursing program. A project was undertaken to evaluate the implementation of this technology and determine its ongoing use. This sequential, exploratory, mixed-methods research…

Haemodialysis work environment contributors to job satisfaction and stress: a sequential mixed methods study.

PubMed

Hayes, Bronwyn; Bonner, Ann; Douglas, Clint

2015-01-01

Haemodialysis nurses form long term relationships with patients in a technologically complex work environment. Previous studies have highlighted that haemodialysis nurses face stressors related to the nature of their work and also their work environments leading to reported high levels of burnout. Using Kanters (1997) Structural Empowerment Theory as a guiding framework, the aim of this study was to explore the factors contributing to satisfaction with the work environment, job satisfaction, job stress and burnout in haemodialysis nurses. Using a sequential mixed-methods design, the first phase involved an on-line survey comprising demographic and work characteristics, Brisbane Practice Environment Measure (B-PEM), Index of Work Satisfaction (IWS), Nursing Stress Scale (NSS) and the Maslach Burnout Inventory (MBI). The second phase involved conducting eight semi-structured interviews with data thematically analyzed. From the 417 nurses surveyed the majority were female (90.9 %), aged over 41 years of age (74.3 %), and 47.4 % had worked in haemodialysis for more than 10 years. Overall the work environment was perceived positively and there was a moderate level of job satisfaction. However levels of stress and emotional exhaustion (burnout) were high. Two themes, ability to care and feeling successful as a nurse, provided clarity to the level of job satisfaction found in phase 1. While two further themes, patients as quasi-family and intense working teams, explained why working as a haemodialysis nurse was both satisfying and stressful. Nurse managers can use these results to identify issues being experienced by haemodialysis nurses working in the unit they are supervising.

From Gatekeeping to Engagement: A Multicontextual, Mixed Method Study of Student Academic Engagement in Introductory STEM Courses.

PubMed

Gasiewski, Josephine A; Eagan, M Kevin; Garcia, Gina A; Hurtado, Sylvia; Chang, Mitchell J

2012-03-01

The lack of academic engagement in introductory science courses is considered by some to be a primary reason why students switch out of science majors. This study employed a sequential, explanatory mixed methods approach to provide a richer understanding of the relationship between student engagement and introductory science instruction. Quantitative survey data were drawn from 2,873 students within 73 introductory science, technology, engineering, and mathematics (STEM) courses across 15 colleges and universities, and qualitative data were collected from 41 student focus groups at eight of these institutions. The findings indicate that students tended to be more engaged in courses where the instructor consistently signaled an openness to student questions and recognizes her/his role in helping students succeed. Likewise, students who reported feeling comfortable asking questions in class, seeking out tutoring, attending supplemental instruction sessions, and collaborating with other students in the course were also more likely to be engaged. Instructional implications for improving students' levels of academic engagement are discussed.

A safety culture assessment by mixed methods at a public maternity and infant hospital in China

PubMed Central

Listyowardojo, Tita Alissa; Yan, Xiaoling; Leyshon, Stephen; Ray-Sannerud, Bobbie; Yu, Xin Yan; Zheng, Kai; Duan, Tao

2017-01-01

Objective To assess safety culture at a public maternity hospital in Shanghai, China, using a sequential mixed methods approach. The study was part of a bigger study looking at the application of the mixed methods approach to assess safety culture in health care in different organizations and countries. Methodology A mixed methods approach was utilized by first distributing the Safety Attitudes Questionnaire measuring six safety culture dimensions and five independent items to all hospital staff (n=1482) working in 18 departments at a single hospital. Afterward, semistructured interviews were conducted using convenience sampling, where 48 hospital staff from nine departments at the same hospital were individually interviewed. Results The survey received a response rate of 96%. The survey findings show significant differences between the hospital departments in almost all safety culture dimensions and independent items. Similarly, the interview findings revealed that there were different, competing priorities between departments perceived to result in a reduced quality of collaboration and bottlenecks in care delivery. Another major finding was that staff who worked more hours per week would perceive working conditions significantly more negatively. Issues related to working conditions were also the most common concerns discussed in the interviews, especially the issue on high workload. High workload was also reflected in the fact that 91.45% of survey respondents reported that they worked 40 hours or longer per week. Finally, interview findings complemented survey findings, thus providing a more complete and accurate picture of safety culture. Conclusion Hospital leaders need to prioritize interventions focused on improving the quality of cross-department collaboration and reducing workload. A mixed methods assessment of safety culture provides more meaningful, targeted results, enabling leaders to prioritize and tailor improvement efforts to increase the impact of an intervention. PMID:28740399

Examining the Personal Nature of the K-14 Engineering Pipeline for Young Women

NASA Astrophysics Data System (ADS)

Gurski, Jennifer Sue

This mixed-methods study examined young women's perceptions of their K-14 STEM pipeline experiences and their resulting choice to enter and persist in an engineering major. Despite the increase of women in the STEM workforce, women remain underrepresented among engineering majors (Beasley & Fischer, 2012; Heilbronner, 2012; Neihart & Teo, 2013). Few studies exist that utilize a retrospective approach to understand how the culmination of young women's K-14 experiences have influenced their formation of individually held perceptions that lead to engineering persistence. It is this study's aim to utilize a mixed-methods approach to answer the following research question: How do young women's perceptions of their K-14 STEM experiences influence their decision to enroll and persist in an engineering major? These perceptions are explored through an ethnographic approach focusing on young women enrolled in engineering programs during their junior and senior years of study at a small private liberal arts university with eight engineering majors. The mixed-methods approach follows a sequential design method (Creswell, 2013) and utilizes questions in a quantitative Likert-type survey from the Academic Pathways for People Learning Engineering (APPLES) survey (Eris, Chachra, Chen, Sheppard, & Ludlow, 2010) and the Motivated Strategy Learning Questionnaire (MSLQ) (Pintrich, Smith, Garcia, & McKeachie, 1991). The quantitative study results will lead to the development of open-ended, structured questions for conducting a qualitative focus group. Anonymity of all participants is maintained. Keywords: STEM, young women, perceptions, pipeline, intervention, underrepresentation, engineering, persistence, retrospective, self-efficacy.

A Game-Theoretic Approach to Information-Flow Control via Protocol Composition

NASA Astrophysics Data System (ADS)

Alvim, Mário; Chatzikokolakis, Konstantinos; Kawamoto, Yusuke; Palamidessi, Catuscia

2018-05-01

In the inference attacks studied in Quantitative Information Flow (QIF), the attacker typically tries to interfere with the system in the attempt to increase its leakage of secret information. The defender, on the other hand, typically tries to decrease leakage by introducing some controlled noise. This noise introduction can be modeled as a type of protocol composition, i.e., a probabilistic choice among different protocols, and its effect on the amount of leakage depends heavily on whether or not this choice is visible to the attacker. In this work, we consider operators for modeling visible and hidden choice in protocol composition, and we study their algebraic properties. We then formalize the interplay between defender and attacker in a game-theoretic framework adapted to the specific issues of QIF, where the payoff is information leakage. We consider various kinds of leakage games, depending on whether players act simultaneously or sequentially, and on whether or not the choices of the defender are visible to the attacker. In the case of sequential games, the choice of the second player is generally a function of the choice of the first player, and his/her probabilistic choice can be either over the possible functions (mixed strategy) or it can be on the result of the function (behavioral strategy). We show that when the attacker moves first in a sequential game with a hidden choice, then behavioral strategies are more advantageous for the defender than mixed strategies. This contrasts with the standard game theory, where the two types of strategies are equivalent. Finally, we establish a hierarchy of these games in terms of their information leakage and provide methods for finding optimal strategies (at the points of equilibrium) for both attacker and defender in the various cases.

Perceptions and experiences of a gender gap at a Canadian research institute and potential strategies to mitigate this gap: a sequential mixed-methods study

PubMed Central

Mascarenhas, Alekhya; Moore, Julia E.; Tricco, Andrea C.; Hamid, Jemila; Daly, Caitlin; Bain, Julie; Jassemi, Sabrina; Kiran, Tara; Baxter, Nancy; Straus, Sharon E.

2017-01-01

Background: The gender gap in academia is long-standing. Failure to ensure that our academic faculty reflect our student pool and national population deprives Canada of talent. We explored the gender distribution and perceptions of the gender gap at a Canadian university-affiliated, hospital-based research institute. Methods: We completed a sequential mixed-methods study. In phase 1, we used the research institute's registry of scientists (1999-2014) and estimated overall prevalence of a gender gap and the gap with respect to job description (e.g., associate v. full-time) and research discipline. In phase 2, we conducted qualitative interviews to provide context for phase 1 data. Both purposive and snowball sampling were used for recruitment. Results: The institute included 30.1% (n = 62) women and 69.9% (n = 144) men, indicating a 39.8% gender gap. Most full-time scientists (60.3%, n = 70) were clinicians; there were 54.2% more male than female clinician scientists. Ninety-five percent of basic scientists were men, indicating a 90.5% gap. Seven key themes emerged from 21 interviews, including perceived impact of the gender gap, factors perceived to influence the gap, recruitment trends, presence of institutional support, mentorship and suggestions to mitigate the gap. Several factors were postulated to contribute to the gender gap, including unconscious bias in hiring. Interpretation: A substantial gender gap exists within this research institute. Participants identified strategies to address this gap, such as establishing transparent search processes, providing opportunities for informal networking and mentorship of female scientists and establishing institutional support for work-life balance. PMID:28401131

Exploring how nurses assess, monitor and manage acute pain for adult critically ill patients in the emergency department: protocol for a mixed methods study.

PubMed

Varndell, Wayne; Fry, Margaret; Elliott, Doug

2017-08-01

Many critically ill patients experience moderate to severe acute pain that is frequently undetected and/or undertreated. Acute pain in this patient cohort not only derives from their injury and/or illness, but also as a consequence of delivering care whilst stabilising the patient. Emergency nurses are increasingly responsible for the safety and wellbeing of critically ill patients, which includes assessing, monitoring and managing acute pain. How emergency nurses manage acute pain in critically ill adult patients is unknown. The objective of this study is to explore how emergency nurses manage acute pain in critically ill patients in the Emergency Department. In this paper, we provide a detailed description of the methods and protocol for a multiphase sequential mixed methods study, exploring how emergency nurses assess, monitor and manage acute pain in critically ill adult patients. The objective, method, data collection and analysis of each phase are explained. Justification of each method and data integration is described. Synthesis of findings will generate a comprehensive picture of how emergency nurses' perceive and manage acute pain in critically ill adult patients. The results of this study will form a knowledge base to expand theory and inform research and practice.

Challenges in predicting climate change impacts on pome fruit phenology

NASA Astrophysics Data System (ADS)

Darbyshire, Rebecca; Webb, Leanne; Goodwin, Ian; Barlow, E. W. R.

2014-08-01

Climate projection data were applied to two commonly used pome fruit flowering models to investigate potential differences in predicted full bloom timing. The two methods, fixed thermal time and sequential chill-growth, produced different results for seven apple and pear varieties at two Australian locations. The fixed thermal time model predicted incremental advancement of full bloom, while results were mixed from the sequential chill-growth model. To further investigate how the sequential chill-growth model reacts under climate perturbed conditions, four simulations were created to represent a wider range of species physiological requirements. These were applied to five Australian locations covering varied climates. Lengthening of the chill period and contraction of the growth period was common to most results. The relative dominance of the chill or growth component tended to predict whether full bloom advanced, remained similar or was delayed with climate warming. The simplistic structure of the fixed thermal time model and the exclusion of winter chill conditions in this method indicate it is unlikely to be suitable for projection analyses. The sequential chill-growth model includes greater complexity; however, reservations in using this model for impact analyses remain. The results demonstrate that appropriate representation of physiological processes is essential to adequately predict changes to full bloom under climate perturbed conditions with greater model development needed.

Evaluating the Reliability and Impact of a Quality Assurance System for E-Learning Courseware

ERIC Educational Resources Information Center

Sung, Yao-Ting; Chang, Kuo-En; Yu, Wen-Cheng

2011-01-01

Assuring e-learning quality is of interest worldwide. This paper introduces the methods of e-learning courseware quality assurance (a quality certification system) adopted by the eLQSC (e-Learning Quality Service Centre) in Taiwan. A sequential/explanatory design with a mixed methodology was used to gather research data and conduct data analyses.…

University Students' Views on the Education and Teaching of Civilization History: Bayburt University Education Faculty Sample

ERIC Educational Resources Information Center

Elban, Mehmet

2017-01-01

The purpose of this research is to evaluate the teaching and educational activities in the civilization history lesson. The model of the research is the exploratory sequential design from mixed research patterns. The appropriate sampling method was used in the research. The qualitative data of the research were collected from 26 students through a…

Efficacy of Webinar Training for Continuing Professional Education: Applications for School Personnel in K-12 Settings

ERIC Educational Resources Information Center

Covington, Julie Anne

2012-01-01

The purpose of the researcher was to evaluate the effectiveness of webinar training for K-12 school personnel in childhood obesity prevention tools and resources provided by the North Carolina Prevention Partners (NCPP). A mixed method sequential research design was used to evaluate the training across the first three levels of the Kirkpatrick…

Serious Game Leverages Productive Negativity to Facilitate Conceptual Change in Undergraduate Molecular Biology: A Mixed-Methods Randomized Controlled Trial

ERIC Educational Resources Information Center

Gauthier, Andrea; Jenkinson, Jodie

2017-01-01

We designed a serious game, MolWorlds, to facilitate conceptual change about molecular emergence by using game mechanics (resource management, immersed 3rd person character, sequential level progression, and 3-star scoring system) to encourage cycles of productive negativity. We tested the value-added effect of game design by comparing and…

Using a Sequential Exploratory Mixed-Method Design to Examine Racial Hyperprivilege in Higher Education

ERIC Educational Resources Information Center

Cabrera, Nolan L.

2011-01-01

Immediately after the election of a person of color to the presidency, the idea of being "postracial" seeped into the national media, essentially claiming that racism was over. According to this author, however, the United States is far from a "postracial" society. He contends that systemic racism continues to inequitably stratify society in favor…

Exploring Cultural Predictors of Military Intervention Success

DTIC Science & Technology

2015-04-01

research employed a sequential, mixed method analysis consisting of a quantitative ex post facto analysis of United Nation’s (UN) interventions... research . Results In spite of the many assumptions and limitation forced upon the research by its ex post facto design, it nonetheless provided some... post facto exploration of predictors of military intervention success. As such, the research examined pre- and post -intervention

ANAEROBIC AND AEROBIC TREATMENT OF CHLORINATED ALIPHATIC COMPOUNDS

EPA Science Inventory

Biological degradation of 12 chlorinated aliphatic compounds (CACs) was assessed in bench-top reactors and in serum bottle tests. Three continuously mixed daily batch-fed reactor systems were evaluated: anaerobic, aerobic, and sequential-anaerobic-aerobic (sequential). Glucose,...

Perceptions and experiences of a gender gap at a Canadian research institute and potential strategies to mitigate this gap: a sequential mixed-methods study.

PubMed

Mascarenhas, Alekhya; Moore, Julia E; Tricco, Andrea C; Hamid, Jemila; Daly, Caitlin; Bain, Julie; Jassemi, Sabrina; Kiran, Tara; Baxter, Nancy; Straus, Sharon E

2017-01-01

The gender gap in academia is long-standing. Failure to ensure that our academic faculty reflect our student pool and national population deprives Canada of talent. We explored the gender distribution and perceptions of the gender gap at a Canadian university-affiliated, hospital-based research institute. We completed a sequential mixed-methods study. In phase 1, we used the research institute's registry of scientists (1999-2014) and estimated overall prevalence of a gender gap and the gap with respect to job description (e.g., associate v. full-time) and research discipline. In phase 2, we conducted qualitative interviews to provide context for phase 1 data. Both purposive and snowball sampling were used for recruitment. The institute included 30.1% ( n = 62) women and 69.9% ( n = 144) men, indicating a 39.8% gender gap. Most full-time scientists (60.3%, n = 70) were clinicians; there were 54.2% more male than female clinician scientists. Ninety-five percent of basic scientists were men, indicating a 90.5% gap. Seven key themes emerged from 21 interviews, including perceived impact of the gender gap, factors perceived to influence the gap, recruitment trends, presence of institutional support, mentorship and suggestions to mitigate the gap. Several factors were postulated to contribute to the gender gap, including unconscious bias in hiring. A substantial gender gap exists within this research institute. Participants identified strategies to address this gap, such as establishing transparent search processes, providing opportunities for informal networking and mentorship of female scientists and establishing institutional support for work-life balance.

Isotopic analysis of N and O in nitrite and nitrate by sequential selective bacterial reduction to N2O

USGS Publications Warehouse

Böhlke, J.K.; Smith, R.L.; Hannon, J.E.

2007-01-01

Nitrite is an important intermediate species in the biogeochemical cycling of nitrogen, but its role in natural aquatic systems is poorly understood. Isotopic data can be used to study the sources and transformations of NO2- in the environment, but methods for independent isotopic analyses of NO2- in the presence of other N species are still new and evolving. This study demonstrates that isotopic analyses of N and O in NO2- can be done by treating whole freshwater or saltwater samples with the denitrifying bacterium Stenotrophomonas nitritireducens, which selectively reduces NO2- to N2O for isotope ratio mass spectrometry. When calibrated with solutions containing NO2- with known isotopic compositions determined independently, reproducible δ15N and δ18O values were obtained at both natural-abundance levels (±0.2−0.5‰ for δ15N and ±0.4−1.0‰ for δ18O) and moderately enriched 15N tracer levels (±20−50‰ for δ15N near 5000‰) for 5−20 nmol of NO2- (1−20 μmol/L in 1−5 mL aliquots). This method is highly selective for NO2-and was used for mixed samples containing both NO2- and NO3- with little or no measurable cross-contamination. In addition, mixed samples that were analyzed with S. nitritireducens were treated subsequently with Pseudomonas aureofaciens to reduce the NO3- in the absence of NO2-, providing isotopic analyses of NO2- and NO3- separately in the same aliquot. Sequential bacterial reduction methods like this one should be useful for a variety of isotopic studies aimed at understanding nitrogen cycling in aquatic environments. A test of these methods in an agricultural watershed in Indiana provides isotopic evidence for both nitrification and denitrification as sources of NO2- in a small stream.

Reduction of cognitive conflict and learning style impact towards student-teacher's misconception load

NASA Astrophysics Data System (ADS)

A'yun, Kurroti; Suyono, Poedjiastoeti, Sri; Bin-Tahir, Saidna Zulfiqar

2017-08-01

The most crucial issue in education is a misconception that is caused by the misconception of the students themselves. Therefore, this study provided the solution to improve the quality of teaching chemistry in the schools through the remediation of misconceptions to the chemistry teacher candidates. This study employed a mixed method approach using concurrent embedded designs where it tended more to the qualitative research, but it still relied on the quantitative research in the assessment of the learning impact. The results of this study were the students with higher levels of cognitive conflict still have high loads of misconceptions (MC), it possibly due to the type of students' learning styles that is the sequential-global balanced. To facilitate the cognitive conflict character and the learning style of sequential-global balanced, the researchers created an integrated worksheet conceptual change with peer learning (WCCPL). The peer learning undertaken in the last stages of conceptual change of WCCPL can increase the resistance of students' concept in a category of knowing the concept significantly, but it should be examined in an in-depth study related to the long-term memory.

How college students conceptualize and practice responsible drinking.

PubMed

Barry, Adam E; Goodson, Patricia

2011-01-01

This study sought to employ a mixed-methods approach to (a) qualitatively explore responsible drinking beliefs and behaviors among a sample of college students, and (b) quantitatively assess the prevalence of those behaviors. Convenience samples, drawn from currently enrolled students attending a large public university in Texas, comprised 13 participants in the qualitative phase and a random sample of 729 students for the quantitative phase. A partially mixed sequential dominant status design (qual → QUAN) was employed. PARTICIPANTS associated 7 distinct themes with drinking responsibly; however, embedded inside these themes were numerous potentially harmful elements. Quantitative findings supported the qualitative themes, also highlighting gender and ethnic differences. Males believed responsible drinking behaviors should occur with significantly less frequency than females, whereas Whites attached less relative necessity to certain responsible drinking behaviors. This study represents an initial attempt to determine specific, evidence-based characteristics of responsible drinking.

Understanding low uptake of contraceptives in resource-limited settings: a mixed-methods study in rural Burundi.

PubMed

Ndayizigiye, M; Fawzi, M C Smith; Lively, C Thompson; Ware, N C

2017-03-15

Family planning can reduce deaths, improve health, and facilitate economic development in resource-limited settings. Yet, modern contraceptive methods are often underused. This mixed-methods study, conducted in rural Burundi, sought to explain low uptake of contraceptives by identifying utilization barriers. Results may inform development of family planning interventions in Burundi and elsewhere. We investigated uptake of contraceptives among women of reproductive age in two rural districts of Burundi, using an explanatory sequential, mixed-methods research design. We first assessed availability and utilization rates of modern contraceptives through a facility-based survey in 39 health clinics. Barriers to uptake of contraceptives were then explored through qualitative interviews (N = 10) and focus groups (N = 7). Contraceptives were generally available in the 39 clinics studied, yet uptake of family planning averaged only 2.96%. Greater uptake was positively associated with the number of health professionals engaged and trained in family planning service provision, and with the number of different types of contraceptives available. Four uptake barriers were identified: (1) lack of providers to administer contraception, (2) lack of fit between available and preferred contraceptive methods, (3) a climate of fear surrounding contraceptive use, and (4) provider refusal to offer family planning services. Where resources are scarce, availability of modern contraceptives alone will likely not ensure uptake. Interventions addressing multiple uptake barriers simultaneously have the greatest chance of success. In rural Burundi, examples are community distribution of contraceptive methods, public information campaigns, improved training for health professionals and community health workers, and strengthening of the health infrastructure.

"Which Mouse Kissed the Frog?" Effects of Age of Onset, Length of Exposure, and Knowledge of Case Marking on the Comprehension of "Wh"-Questions in German-Speaking Simultaneous and Early Sequential Bilingual Children

ERIC Educational Resources Information Center

Roesch, Anne Dorothee; Chondrogianni, Vasiliki

2016-01-01

Studies examining age of onset (AoO) effects in childhood bilingualism have provided mixed results as to whether early sequential bilingual children (eL2) differ from simultaneous bilingual children (2L1) and L2 children on the acquisition of morphosyntax. Differences between the three groups have been attributed to other factors such as length of…

What supports hospital pharmacist prescribing in Scotland? - A mixed methods, exploratory sequential study.

PubMed

Fisher, J; Kinnear, M; Reid, F; Souter, C; Stewart, D

2018-05-01

While approximately half of all qualified hospital pharmacist independent prescribers (PIPs) in Scotland are active prescribers, there are major differences in prescribing activity across geographical areas. This study aimed to explore, through focus groups, interviews and a questionnaire, hospital PIPs' perceptions of factors associated with prescribing activity and to investigate the infrastructure required to better support active prescribing by PIPs. Findings reinforced the perceived positive impact of supportive pharmacy leadership within the organisation, recognition that prescribing is integral to the clinical pharmacist role and a work environment conducive to prescribing. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Explaining the Impact of Disabled Children's Engagement with Physical Activity on Their Parents' Smartphone Addiction Levels: A Sequential Explanatory Mixed Methods Research

ERIC Educational Resources Information Center

Gündogdu, Cemal; Aygün, Yalin; Ilkim, Mehmet; Tüfekçi, Sakir

2018-01-01

In this research, quantitative findings and qualitative follow-up themes were used to quantify, conceptualize and finally try to explain the impact of disabled children's engagement with physical activity on their parents' smartphone addiction levels. An initial phase of quantitative investigation was conducted with 116 parents. Analyses of…

The Importance of Context in Screening in Occupational Health Interventions in Organizations: A Mixed Methods Study.

PubMed

Vignoli, Michela; Nielsen, Karina; Guglielmi, Dina; Tabanelli, Maria C; Violante, Francesco S

2017-01-01

In occupational health interventions, there is a debate as to whether standardized or tailored measures should be used to identify which aspects of the psychosocial work environment should be targeted in order to improve employees' well-being. Using the Job Demands-Resources model, the main aim of the present study is to demonstrate how a mixed methods approach to conducting screening enables the identification of potential context-dependent demands and resources in the workplace, which should to be targeted by the intervention. Specifically, we used a mixed methods exploratory sequential research design. First, we conducted four focus groups ( N = 37) in a sample of employees working in grocery stores in Italy. The qualitative results allowed to identify one possible context-specific job demand: the use of a work scheduling IT software, whose implementation resulted in a high rotation between different market's departments. From the qualitative results, this context-specific demand seemed to be related to workers' well-being. Thus, in a subsequent questionnaire survey ( N = 288), we included this demand together with generic measures of social support and psychological well-being. Results confirmed that this context-specific job demand was related to emotional exhaustion. Furthermore, it was found that social support moderated the relationship between this specific job demand and emotional exhaustion showing among employees whose activities depended on the IT software, employees that perceived higher levels of social support from colleagues experienced lower levels of emotional exhaustion with respect to their colleagues who perceived lower levels of social support. The present study confirms that mixed methods approach is useful in occupational health intervention research and offers a way forward on helping organizations prioritize their intervention activities.

The Importance of Context in Screening in Occupational Health Interventions in Organizations: A Mixed Methods Study

PubMed Central

Vignoli, Michela; Nielsen, Karina; Guglielmi, Dina; Tabanelli, Maria C.; Violante, Francesco S.

2017-01-01

In occupational health interventions, there is a debate as to whether standardized or tailored measures should be used to identify which aspects of the psychosocial work environment should be targeted in order to improve employees’ well-being. Using the Job Demands-Resources model, the main aim of the present study is to demonstrate how a mixed methods approach to conducting screening enables the identification of potential context-dependent demands and resources in the workplace, which should to be targeted by the intervention. Specifically, we used a mixed methods exploratory sequential research design. First, we conducted four focus groups (N = 37) in a sample of employees working in grocery stores in Italy. The qualitative results allowed to identify one possible context-specific job demand: the use of a work scheduling IT software, whose implementation resulted in a high rotation between different market’s departments. From the qualitative results, this context-specific demand seemed to be related to workers’ well-being. Thus, in a subsequent questionnaire survey (N = 288), we included this demand together with generic measures of social support and psychological well-being. Results confirmed that this context-specific job demand was related to emotional exhaustion. Furthermore, it was found that social support moderated the relationship between this specific job demand and emotional exhaustion showing among employees whose activities depended on the IT software, employees that perceived higher levels of social support from colleagues experienced lower levels of emotional exhaustion with respect to their colleagues who perceived lower levels of social support. The present study confirms that mixed methods approach is useful in occupational health intervention research and offers a way forward on helping organizations prioritize their intervention activities. PMID:28848468

The Department of Defense and Homeland Security relationship: Hurricane Katrina through Hurricane Irene.

PubMed

Weaver, John Michael

2015-01-01

This research explored federal intervention with the particular emphasis on examining how a collaborative relationship between Department of Defense (DOD) and Homeland Security (DHS) led to greater effectiveness between these two federal departments and their subordinates (United States Northern Command and Federal Emergency Management Agency, respectively) during the preparation and response phases of the disaster cycle regarding US continental-based hurricanes. Through the application of a two-phased, sequential mixed methods approach, this study determined how their relationship has led to longitudinal improvements in the years following Hurricane Katrina, focusing on hurricanes as the primary unit of analysis.

Using mixed-methods research to study the quality of life of coeliac women.

PubMed

Rodríguez Almagro, Julián; Hernández Martínez, Antonio; Solano Ruiz, María Carmen; Siles González, José

2017-04-01

To research the quality of life of Spanish women with coeliac disease. Women with coeliac disease express lower quality of life than men with coeliac disease. Explanatory sequential approach using mixed methods and with a gender perspective. The research was carried out between May and July 2015. In its quantitative stage, it aimed to determine the health-related quality of life in a representative sample (n = 1097) of Spanish adult women with coeliac disease using a specific questionnaire named Coeliac Disease-Quality of Life. In its qualitative phase, it aimed to describe the life experiences of a woman with coeliac disease in a qualitative manner by means of interviews (n = 19) with a semistructured script. Quantitative data were analysed using spss version 20 and presented in descriptive statistics. Qualitative data were analysed using the directed content analysis. The quantitative process gave us the values on the four aspects studied: dysphoria, disease limitations, health problems and inadequate treatment. These aspects allowed us to create a qualitative process, based on which we generated an interview, from which four larger categories emerged. These categories were feelings at diagnosis, limitations in day-to-day life, social perceptions of the disease and personal meanings of coeliac disease. Thus, both phases of our project are totally connected. There was a high level of congruence between quantitative scores and narratives. This study shows us the strong points of mixed-methods strategy in health sciences. The mixed-methods strategy gave us a wider view of the experience of women living with coeliac disease. In our case, a strength and not a limitation is having performed the quality of life study in women with coeliac disease using a mixed methodology, approaching the experience of being a woman with coeliac disease in Spain in two different but complementary ways. The quantitative and qualitative data allowed us to interpret the experiences of our participants. © 2016 John Wiley & Sons Ltd.

Liquid mixing enhanced by pulse width modulation in a Y-shaped jet configuration

NASA Astrophysics Data System (ADS)

Xia, Qingfeng; Zhong, Shan

2013-04-01

In this paper, mixing between two fluid streams, which are injected into a planar mixing channel via a Y-shaped confluence section at the same volume flow rate, is studied experimentally. The injection of the two fluid streams is controlled by two separate solenoid valves, which are operated with a phase difference of 180°, using pulse width modulation. The experiments are conducted using water at a mean Reynolds number between 83 and 250, a range of pulsation frequencies and two duty cycles (25 and 50%). Both particle-image velocimetry and planar laser-induced fluorescence technique are used to visualize the flow patterns and to quantify the mixing degree in the mixing channel. This experiment shows that the pulsation of each jet produces vortical structures, which promotes mixing via vortex entrainment and vortex breakup, and at the same time the mixing is also greatly enhanced by sequential segmentation produced by a 180° out-of-phase pulsation of the two jets. This mixing enhancement method is effective at a Reynolds number greater than 125 with a mixing degree of 0.9 being achieved. For the Reynolds numbers studied in the present experiments, an optimal frequency exists, which corresponds to a Strouhal number in the range of 0.5-2. Furthermore, at a given mean Reynolds number a lower duty cycle is found to produce a better mixing due to the resultant higher instantaneous Reynolds number in the jet flow. It is also found that pulsation of only one jet can produce a similar mixing effect.

A mixed-methods pilot study of the acceptability and effectiveness of a brief meditation and mindfulness intervention for people with diabetes and coronary heart disease.

PubMed

Keyworth, Chris; Knopp, Jasmin; Roughley, Kate; Dickens, Chris; Bold, Stuart; Coventry, Peter

2014-01-01

Mindfulness-based interventions can successfully target negative perseverative cognitions such as worry and thought suppression, but their acceptability and effectiveness in people with long-term conditions is uncertain. We therefore pilot tested a six-week meditation and mindfulness intervention in people (n = 40) with diabetes mellitus and coronary heart disease. We used a sequential mixed-methods approach that measured change in worry and thought suppression and qualitatively explored acceptability, feasibility, and user experience with a focus group (n = 11) and in-depth interviews (n = 16). The intervention was highly acceptable, with 90% completing ≥5 sessions. Meditation and mindfulness skills led to improved sleep, greater relaxation, and more-accepting approaches to illness and illness experience. At the end of the six-week meditation course, worry, and thought suppression were significantly reduced. Positive impacts of mindfulness-based interventions on psychological health may relate to acquisition and development of meta-cognitive skills but this needs experimental confirmation.

Method for efficient recovery of high-purity polycarbonates from electronic waste.

PubMed

Weeden, George S; Soepriatna, Nicholas H; Wang, Nien-Hwa Linda

2015-02-17

More than one million tons of polycarbonates from waste electrical and electronic equipment are consigned to landfills at an increasing rate of 3-5% per year. Recycling the polymer waste should have a major environmental impact. Pure solvents cannot be used to selectively extract polycarbonates from mixtures of polymers with similar properties. In this study, selective mixed solvents are found using guidelines from Hansen solubility parameters, gradient polymer elution chromatography, and solubility tests. A room-temperature sequential extraction process using two mixed solvents is developed to recover polycarbonates with high yield (>95%) and a similar purity and molecular weight distribution as virgin polycarbonates. The estimated cost of recovery is less than 30% of the cost of producing virgin polycarbonates from petroleum. This method would potentially reduce raw materials from petroleum, use 84% less energy, reduce emission by 1-6 tons of CO2 per ton of polycarbonates, and reduce polymer accumulation in landfills and associated environmental hazards.

A Mixed-Methods Pilot Study of the Acceptability and Effectiveness of a Brief Meditation and Mindfulness Intervention for People with Diabetes and Coronary Heart Disease

PubMed Central

Keyworth, Chris; Knopp, Jasmin; Roughley, Kate; Dickens, Chris; Bold, Stuart; Coventry, Peter

2014-01-01

Mindfulness-based interventions can successfully target negative perseverative cognitions such as worry and thought suppression, but their acceptability and effectiveness in people with long-term conditions is uncertain. We therefore pilot tested a six-week meditation and mindfulness intervention in people (n = 40) with diabetes mellitus and coronary heart disease. We used a sequential mixed-methods approach that measured change in worry and thought suppression and qualitatively explored acceptability, feasibility, and user experience with a focus group (n = 11) and in-depth interviews (n = 16). The intervention was highly acceptable, with 90% completing ≥5 sessions. Meditation and mindfulness skills led to improved sleep, greater relaxation, and more-accepting approaches to illness and illness experience. At the end of the six-week meditation course, worry, and thought suppression were significantly reduced. Positive impacts of mindfulness-based interventions on psychological health may relate to acquisition and development of meta-cognitive skills but this needs experimental confirmation. PMID:24754440

The Complexities of Family Caregiving at Work: A Mixed-Methods Study.

PubMed

Gaugler, Joseph E; Pestka, Deborah L; Davila, Heather; Sales, Rebecca; Owen, Greg; Baumgartner, Sarah A; Shook, Rocky; Cunningham, Jane; Kenney, Maureen

2018-01-01

The current project examined the impact of caregiving and caregiving-work conflict on employees' well-being. A sequential explanatory mixed-methods design (QUAN→qual) was utilized, and a total of 880 employees from a large health-care plan employer completed an online survey. Forty-five caregivers who completed the survey also participated in one of the five focus groups held 1 to 2 months later. Employed caregivers were significantly ( p < .05) more likely to indicate poorer physical and mental health than noncaregivers; among caregivers ( n = 370), caregiving-work conflict emerged as the most significant predictor of well-being and fully mediated the empirical relationship between burden and well-being. The focus group findings complemented the quantitative results; many of the challenges employed caregivers experience stem from their ability or inability to effectively balance their employment and caregiving roles. The results suggest the need to focus on caregiving-work conflict when constructing new or translating existing evidence-based caregiver interventions.

Self-Consistent Chaotic Transport in a High-Dimensional Mean-Field Hamiltonian Map Model

DOE PAGES

Martínez-del-Río, D.; del-Castillo-Negrete, D.; Olvera, A.; ...

2015-10-30

We studied the self-consistent chaotic transport in a Hamiltonian mean-field model. This model provides a simplified description of transport in marginally stable systems including vorticity mixing in strong shear flows and electron dynamics in plasmas. Self-consistency is incorporated through a mean-field that couples all the degrees-of-freedom. The model is formulated as a large set of N coupled standard-like area-preserving twist maps in which the amplitude and phase of the perturbation, rather than being constant like in the standard map, are dynamical variables. Of particular interest is the study of the impact of periodic orbits on the chaotic transport and coherentmore » structures. Furthermore, numerical simulations show that self-consistency leads to the formation of a coherent macro-particle trapped around the elliptic fixed point of the system that appears together with an asymptotic periodic behavior of the mean field. To model this asymptotic state, we introduced a non-autonomous map that allows a detailed study of the onset of global transport. A turnstile-type transport mechanism that allows transport across instantaneous KAM invariant circles in non-autonomous systems is discussed. As a first step to understand transport, we study a special type of orbits referred to as sequential periodic orbits. Using symmetry properties we show that, through replication, high-dimensional sequential periodic orbits can be generated starting from low-dimensional periodic orbits. We show that sequential periodic orbits in the self-consistent map can be continued from trivial (uncoupled) periodic orbits of standard-like maps using numerical and asymptotic methods. Normal forms are used to describe these orbits and to find the values of the map parameters that guarantee their existence. Numerical simulations are used to verify the prediction from the asymptotic methods.« less

Self-Consistent Chaotic Transport in a High-Dimensional Mean-Field Hamiltonian Map Model

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

Martínez-del-Río, D.; del-Castillo-Negrete, D.; Olvera, A.

We studied the self-consistent chaotic transport in a Hamiltonian mean-field model. This model provides a simplified description of transport in marginally stable systems including vorticity mixing in strong shear flows and electron dynamics in plasmas. Self-consistency is incorporated through a mean-field that couples all the degrees-of-freedom. The model is formulated as a large set of N coupled standard-like area-preserving twist maps in which the amplitude and phase of the perturbation, rather than being constant like in the standard map, are dynamical variables. Of particular interest is the study of the impact of periodic orbits on the chaotic transport and coherentmore » structures. Furthermore, numerical simulations show that self-consistency leads to the formation of a coherent macro-particle trapped around the elliptic fixed point of the system that appears together with an asymptotic periodic behavior of the mean field. To model this asymptotic state, we introduced a non-autonomous map that allows a detailed study of the onset of global transport. A turnstile-type transport mechanism that allows transport across instantaneous KAM invariant circles in non-autonomous systems is discussed. As a first step to understand transport, we study a special type of orbits referred to as sequential periodic orbits. Using symmetry properties we show that, through replication, high-dimensional sequential periodic orbits can be generated starting from low-dimensional periodic orbits. We show that sequential periodic orbits in the self-consistent map can be continued from trivial (uncoupled) periodic orbits of standard-like maps using numerical and asymptotic methods. Normal forms are used to describe these orbits and to find the values of the map parameters that guarantee their existence. Numerical simulations are used to verify the prediction from the asymptotic methods.« less

A Sequential Linear Quadratic Approach for Constrained Nonlinear Optimal Control with Adaptive Time Discretization and Application to Higher Elevation Mars Landing Problem

NASA Astrophysics Data System (ADS)

Sandhu, Amit

A sequential quadratic programming method is proposed for solving nonlinear optimal control problems subject to general path constraints including mixed state-control and state only constraints. The proposed algorithm further develops on the approach proposed in [1] with objective to eliminate the use of a high number of time intervals for arriving at an optimal solution. This is done by introducing an adaptive time discretization to allow formation of a desirable control profile without utilizing a lot of intervals. The use of fewer time intervals reduces the computation time considerably. This algorithm is further used in this thesis to solve a trajectory planning problem for higher elevation Mars landing.

Methodological and practical viewpoints of qualitative-driven mixed method design: the case of decentralisation of primary healthcare services in Nepal.

PubMed

Regmi, Krishna

2018-01-01

Although considerable attention has been paid to the use of quantitative methods in health research, there has been limited focus on decentralisation research using a qualitative-driven mixed method design. Decentralisation presents both a problematic concept and methodological challenges, and is more context-specific and is often multi-dimensional. Researchers often consider using more than one method design when researching phenomena is complex in nature. Aim To explore the effects of decentralisation on the provision of primary healthcare services. Qualitative-driven mixed method design, employing three methods of data collections: focus group discussions (FGDs), semi-structured interviews (SSIs) and participant observations under two components, that is, core component and supplementary components were used. Four FGDs with health service practitioners, three FGDs with district stakeholders, 20 SSIs with health service users and 20 SSIs with national stakeholders were carried out. These were conducted sequentially. NVivo10, a data management program, was utilised to code the field data, employing a content analysis method for searching the underlying themes or concepts in the text material. Findings Both positive and negative experiences related to access, quality, planning, supplies, coordination and supervision were identified. This study suggests some evidence of the effects of decentralisation on health outcomes in general, as well as filling a gap of understanding and examining healthcare through a qualitative-driven mixed methods approach, in particular. Future research in the area of qualitative in-depth understanding of the problems (why decentralisation, why now and what for) would provoke an important data set that benefits the researchers and policy-makers for planning and implementing effective health services.

Desirable role in a price-setting international mixed duopoly

NASA Astrophysics Data System (ADS)

Ferreira, Fernanda A.; Ferreira, Flávio

2011-12-01

In this paper, we study the order of moves in a mixed international duopoly for differentiated goods, where firms choose whether to set prices sequentially or simultaneously. We discuss the desirable role of the public firm by comparing welfare among three games. We find that, in the three possible roles, the domestic public firm put a lower price, and then produces more than the foreign private firm.

Race and Older Mothers’ Differentiation: A Sequential Quantitative and Qualitative Analysis

PubMed Central

Sechrist, Jori; Suitor, J. Jill; Riffin, Catherine; Taylor-Watson, Kadari; Pillemer, Karl

2011-01-01

The goal of this paper is to demonstrate a process by which qualitative and quantitative approaches are combined to reveal patterns in the data that are unlikely to be detected and confirmed by either method alone. Specifically, we take a sequential approach to combining qualitative and quantitative data to explore race differences in how mothers differentiate among their adult children. We began with a standard multivariate analysis examining race differences in mothers’ differentiation among their adult children regarding emotional closeness and confiding. Finding no race differences in this analysis, we conducted an in-depth comparison of the Black and White mothers’ narratives to determine whether there were underlying patterns that we had been unable to detect in our first analysis. Using this method, we found that Black mothers were substantially more likely than White mothers to emphasize interpersonal relationships within the family when describing differences among their children. In our final step, we developed a measure of familism based on the qualitative data and conducted a multivariate analysis to confirm the patterns revealed by the in-depth comparison of the mother’s narratives. We conclude that using such a sequential mixed methods approach to data analysis has the potential to shed new light on complex family relations. PMID:21967639

Integration deficiencies associated with continuous limb movement sequences in Parkinson's disease.

PubMed

Park, Jin-Hoon; Stelmach, George E

2009-11-01

The present study examined the extent to which Parkinson's disease (PD) influences integration of continuous limb movement sequences. Eight patients with idiopathic PD and 8 age-matched normal subjects were instructed to perform repetitive sequential aiming movements to specified targets under three-accuracy constraints: 1) low accuracy (W = 7 cm) - minimal accuracy constraint, 2) high accuracy (W = 0.64 cm) - maximum accuracy constraint, and 3) mixed accuracy constraint - one target of high accuracy and another target of low accuracy. The characteristic of sequential movements in the low accuracy condition was mostly cyclical, whereas in the high accuracy condition it was discrete in both groups. When the accuracy constraint was mixed, the sequential movements were executed by assembling discrete and cyclical movements in both groups, suggesting that for PD patients the capability to combine discrete and cyclical movements to meet a task requirement appears to be intact. However, such functional linkage was not as pronounced as was in normal subjects. Close examination of movement from the mixed accuracy condition revealed marked movement hesitations in the vicinity of the large target in PD patients, resulting in a bias toward discrete movement. These results suggest that PD patients may have deficits in ongoing planning and organizing processes during movement execution when the tasks require to assemble various accuracy requirements into more complex movement sequences.

Performance analysis of coherent free space optical communications with sequential pyramid wavefront sensor

NASA Astrophysics Data System (ADS)

Liu, Wei; Yao, Kainan; Chen, Lu; Huang, Danian; Cao, Jingtai; Gu, Haijun

2018-03-01

Based-on the previous study on the theory of the sequential pyramid wavefront sensor (SPWFS), in this paper, the SPWFS is first applied to the coherent free space optical communications (FSOC) with more flexible spatial resolution and higher sensitivity than the Shack-Hartmann wavefront sensor, and with higher uniformity of intensity distribution and much simpler than the pyramid wavefront sensor. Then, the mixing efficiency (ME) and the bit error rate (BER) of the coherent FSOC are analyzed during the aberrations correction through numerical simulation with binary phase shift keying (BPSK) modulation. Finally, an experimental AO system based-on SPWFS is setup, and the experimental data is used to analyze the ME and BER of homodyne detection with BPSK modulation. The results show that the AO system based-on SPWFS can increase ME and decrease BER effectively. The conclusions of this paper provide a new method of wavefront sensing for designing the AO system for a coherent FSOC system.

Sequencing small genomic targets with high efficiency and extreme accuracy

PubMed Central

Schmitt, Michael W.; Fox, Edward J.; Prindle, Marc J.; Reid-Bayliss, Kate S.; True, Lawrence D.; Radich, Jerald P.; Loeb, Lawrence A.

2015-01-01

The detection of minority variants in mixed samples demands methods for enrichment and accurate sequencing of small genomic intervals. We describe an efficient approach based on sequential rounds of hybridization with biotinylated oligonucleotides, enabling more than one-million fold enrichment of genomic regions of interest. In conjunction with error correcting double-stranded molecular tags, our approach enables the quantification of mutations in individual DNA molecules. PMID:25849638

Characteristics of vertigo and the affected vestibular nerve systems in idiopathic bilateral vestibulopathy.

PubMed

Fujimoto, Chisato; Kinoshita, Makoto; Kamogashira, Teru; Egami, Naoya; Sugasawa, Keiko; Yamasoba, Tatsuya; Iwasaki, Shinichi

2016-01-01

Vertigo attacks in IBV patients involving both the superior and inferior vestibular nerve systems were significantly more severe than vertigo attacks in patients with selective involvement of the inferior vestibular nerve system alone. To investigate the relationship between the frequency and duration of vertigo and the affected vestibular nerve system in idiopathic bilateral vestibulopathy (IBV). This study categorized 44 IBV patients into the following three sub-groups according to the affected vestibular nerve system: superior, inferior, and mixed type. These patients were also categorized into the following three sub-groups according to their clinical time course: progressive type showing no episodes of vertigo, sequential type showing recurrent vertigo attacks and single-attack type showing a single episode of vertigo. Ten, 11 and 23 patients were classified as the superior, the inferior, and the mixed type, respectively. Seventeen, 23, and four patients were classified as the progressive, the sequential, and the single-attack type, respectively. For the patients having one or more vertigo attacks, the duration of the vertigo attack was longer than 24 h in 69% of the mixed type, and the duration of vertigo in the mixed type was significantly longer than that in the inferior type (p < 0.05).

Microwave Ablation: Comparison of Simultaneous and Sequential Activation of Multiple Antennas in Liver Model Systems

PubMed Central

Harari, Colin M.; Magagna, Michelle; Bedoya, Mariajose; Lee, Fred T.; Lubner, Meghan G.; Hinshaw, J. Louis; Ziemlewicz, Timothy

2016-01-01

Purpose To compare microwave ablation zones created by using sequential or simultaneous power delivery in ex vivo and in vivo liver tissue. Materials and Methods All procedures were approved by the institutional animal care and use committee. Microwave ablations were performed in both ex vivo and in vivo liver models with a 2.45-GHz system capable of powering up to three antennas simultaneously. Two- and three-antenna arrays were evaluated in each model. Sequential and simultaneous ablations were created by delivering power (50 W ex vivo, 65 W in vivo) for 5 minutes per antenna (10 and 15 minutes total ablation time for sequential ablations, 5 minutes for simultaneous ablations). Thirty-two ablations were performed in ex vivo bovine livers (eight per group) and 28 in the livers of eight swine in vivo (seven per group). Ablation zone size and circularity metrics were determined from ablations excised postmortem. Mixed effects modeling was used to evaluate the influence of power delivery, number of antennas, and tissue type. Results On average, ablations created by using the simultaneous power delivery technique were larger than those with the sequential technique (P < .05). Simultaneous ablations were also more circular than sequential ablations (P = .0001). Larger and more circular ablations were achieved with three antennas compared with two antennas (P < .05). Ablations were generally smaller in vivo compared with ex vivo. Conclusion The use of multiple antennas and simultaneous power delivery creates larger, more confluent ablations with greater temperatures than those created with sequential power delivery. © RSNA, 2015 PMID:26133361

NTCP reduction for advanced head and neck cancer patients using proton therapy for complete or sequential boost treatment versus photon therapy.

PubMed

Jakobi, Annika; Stützer, Kristin; Bandurska-Luque, Anna; Löck, Steffen; Haase, Robert; Wack, Linda-Jacqueline; Mönnich, David; Thorwarth, Daniel; Perez, Damien; Lühr, Armin; Zips, Daniel; Krause, Mechthild; Baumann, Michael; Perrin, Rosalind; Richter, Christian

2015-01-01

To determine by treatment plan comparison differences in toxicity risk reduction for patients with head and neck squamous cell carcinoma (HNSCC) from proton therapy either used for complete treatment or sequential boost treatment only. For 45 HNSCC patients, intensity-modulated photon (IMXT) and proton (IMPT) treatment plans were created including a dose escalation via simultaneous integrated boost with a one-step adaptation strategy after 25 fractions for sequential boost treatment. Dose accumulation was performed for pure IMXT treatment, pure IMPT treatment and for a mixed modality treatment with IMXT for the elective target followed by a sequential boost with IMPT. Treatment plan evaluation was based on modern normal tissue complication probability (NTCP) models for mucositis, xerostomia, aspiration, dysphagia, larynx edema and trismus. Individual NTCP differences between IMXT and IMPT (∆NTCPIMXT-IMPT) as well as between IMXT and the mixed modality treatment (∆NTCPIMXT-Mix) were calculated. Target coverage was similar in all three scenarios. NTCP values could be reduced in all patients using IMPT treatment. However, ∆NTCPIMXT-Mix values were a factor 2-10 smaller than ∆NTCPIMXT-IMPT. Assuming a threshold of ≥ 10% NTCP reduction in xerostomia or dysphagia risk as criterion for patient assignment to IMPT, less than 15% of the patients would be selected for a proton boost, while about 50% would be assigned to pure IMPT treatment. For mucositis and trismus, ∆NTCP ≥ 10% occurred in six and four patients, respectively, with pure IMPT treatment, while no such difference was identified with the proton boost. The use of IMPT generally reduces the expected toxicity risk while maintaining good tumor coverage in the examined HNSCC patients. A mixed modality treatment using IMPT solely for a sequential boost reduces the risk by 10% only in rare cases. In contrast, pure IMPT treatment may be reasonable for about half of the examined patient cohort considering the toxicities xerostomia and dysphagia, if a feasible strategy for patient anatomy changes is implemented.

Efficacy of premixed versus sequential administration of clonidine as an adjuvant to hyperbaric bupivacaine intrathecally in cesarean section

PubMed Central

Sachan, Prachee; Kumar, Nidhi; Sharma, Jagdish Prasad

2014-01-01

Background: Density of the drugs injected intrathecally is an important factor that influences spread in the cerebrospinal fluid. Mixing adjuvants with local anesthetics (LA) alters their density and hence their spread compared to when given sequentially in seperate syringes. Aims: To evaluate the efficacy of intrathecal administration of hyperbaric bupivacaine (HB) and clonidine as a mixture and sequentially in terms of block characteristics, hemodynamics, neonatal outcome, and postoperative pain. Setting and Design: Prospective randomized single blind study at a tertiary center from 2010 to 2012. Materials and Methods: Ninety full-term parturient scheduled for elective cesarean sections were divided into three groups on the basis of technique of intrathecal drug administration. Group M received mixture of 75 μg clonidine and 10 mg HB 0.5%. Group A received 75 μg clonidine after administration of 10 mg HB 0.5% through separate syringe. Group B received 75 μg clonidine before HB 0.5% (10 mg) through separate syringe. Statistical analysis used: Observational descriptive statistics, analysis of variance with Bonferroni multiple comparison post hoc test, and Chi-square test. Results: Time to achieve complete sensory and motor block was less in group A and B in which drugs were given sequentially. Duration of analgesia lasted longer in group B (474.3 ± 20.79 min) and group A (472.50 ± 22.11 min) than in group M (337 ± 18.22 min) with clinically insignificant influence on hemodynamic parameters and sedation. Conclusion: Sequential technique reduces time to achieve complete sensory and motor block, delays block regression, and significantly prolongs the duration of analgesia. However, it did not matter much whether clonidine was administered before or after HB. PMID:25886098

Subjective memory impairment in general practice : Short overview and design of a mixed methods study.

PubMed

Pentzek, Michael; Leve, Verena; Leucht, Verena

2017-05-01

Public awareness for dementia is rising and patients with concerns about forgetfulness are not uncommon in general practice. For the general practitioner (GP) subjectively perceived memory impairment (SMI) also offers a chance to broach the issue of cognitive function with the patient. This may support GPs' patient-centered care in terms of a broader frailty concept. What is SMI (definition, operationalization, prevalence and burden)? Which conceptions and approaches do GPs have regarding SMI? Narrative overview of recent SMI criteria and results, selective utilization of results from a systematic literature search on GP dementia care, non-systematic search regarding SMI in general practice, deduction of a study design from the overview and development according to international standards. Studies revealed that approximately 60% of GP patients aged >74 reported a declining memory, every sixth person had concerns about this aspect and only relatively few seek medical advice. Concerns about SMI are considered a risk factor for future dementia. Specific general practice conceptions about SMI could not be identified in the literature. Using guidelines for mixed methods research, the design of an exploratory sequential mixed methods study is presented, which should reveal different attitudes of GPs towards SMI. Subjective memory impairment (SMI) is a common feature and troubles a considerable proportion of patients. Neuropsychiatric research is progressing, but for the transfer of the SMI concept into routine practice, involvement of GP research is necessary. A new study aims to make a contribution to this.

Applying Sparse Machine Learning Methods to Twitter: Analysis of the 2012 Change in Pap Smear Guidelines. A Sequential Mixed-Methods Study.

PubMed

Lyles, Courtney Rees; Godbehere, Andrew; Le, Gem; El Ghaoui, Laurent; Sarkar, Urmimala

2016-06-10

It is difficult to synthesize the vast amount of textual data available from social media websites. Capturing real-world discussions via social media could provide insights into individuals' opinions and the decision-making process. We conducted a sequential mixed methods study to determine the utility of sparse machine learning techniques in summarizing Twitter dialogues. We chose a narrowly defined topic for this approach: cervical cancer discussions over a 6-month time period surrounding a change in Pap smear screening guidelines. We applied statistical methodologies, known as sparse machine learning algorithms, to summarize Twitter messages about cervical cancer before and after the 2012 change in Pap smear screening guidelines by the US Preventive Services Task Force (USPSTF). All messages containing the search terms "cervical cancer," "Pap smear," and "Pap test" were analyzed during: (1) January 1-March 13, 2012, and (2) March 14-June 30, 2012. Topic modeling was used to discern the most common topics from each time period, and determine the singular value criterion for each topic. The results were then qualitatively coded from top 10 relevant topics to determine the efficiency of clustering method in grouping distinct ideas, and how the discussion differed before vs. after the change in guidelines . This machine learning method was effective in grouping the relevant discussion topics about cervical cancer during the respective time periods (~20% overall irrelevant content in both time periods). Qualitative analysis determined that a significant portion of the top discussion topics in the second time period directly reflected the USPSTF guideline change (eg, "New Screening Guidelines for Cervical Cancer"), and many topics in both time periods were addressing basic screening promotion and education (eg, "It is Cervical Cancer Awareness Month! Click the link to see where you can receive a free or low cost Pap test.") It was demonstrated that machine learning tools can be useful in cervical cancer prevention and screening discussions on Twitter. This method allowed us to prove that there is publicly available significant information about cervical cancer screening on social media sites. Moreover, we observed a direct impact of the guideline change within the Twitter messages.

Mixed polymer brushes by sequential polymer addition: anchoring layer effect.

PubMed

Draper, John; Luzinov, Igor; Minko, Sergiy; Tokarev, Igor; Stamm, Manfred

2004-05-11

Smart surfaces can be described as surfaces that have the ability to respond in a controllable fashion to specific environmental stimuli. A heterogeneous (mixed) polymer brush (HPB) can provide a synthetic route to designing smart polymer surfaces. In this research we study HPB comprised of end-grafted polystyrene (PS) and poly(2-vinyl pyridine) (P2VP). The synthesis of the HPB involves the use of an "intermolecular glue" acting as a binding/anchoring interlayer between the polymer brush and the substrate, a silicon wafer. We compare anchoring layers of epoxysilane (GPS), which forms a self-assembled monolayer with epoxy functionality, to poly(glycidyl methacrylate) (PGMA), which forms a macromolecular monolayer with epoxy functionality. The PS and P2VP were deposited onto the wafers in a sequential fashion to chemically graft PS in a first step and subsequently graft P2VP. Rinsing the HPB in selective solvents and observing the change in water contact angle as a function of the HPB composition studied the switching nature of the HPB. Scanning probe microscopy was used to probe the topography and phase imagery of the HPB. The nature of the anchoring layer significantly affected the wettability and morphology of the mixed brushes.

Methamphetamine-alcohol interactions in murine models of sequential and simultaneous oral drug-taking.

PubMed

Fultz, Elissa K; Martin, Douglas L; Hudson, Courtney N; Kippin, Tod E; Szumlinski, Karen K

2017-08-01

A high degree of co-morbidity exists between methamphetamine (MA) addiction and alcohol use disorders and both sequential and simultaneous MA-alcohol mixing increases risk for co-abuse. As little preclinical work has focused on the biobehavioral interactions between MA and alcohol within the context of drug-taking behavior, we employed simple murine models of voluntary oral drug consumption to examine how prior histories of either MA- or alcohol-taking influence the intake of the other drug. In one study, mice with a 10-day history of binge alcohol-drinking [5,10, 20 and 40% (v/v); 2h/day] were trained to self-administer oral MA in an operant-conditioning paradigm (10-40mg/L). In a second study, mice with a 10-day history of limited-access oral MA-drinking (5, 10, 20 and 40mg/L; 2h/day) were presented with alcohol (5-40% v/v; 2h/day) and then a choice between solutions of 20% alcohol, 10mg/L MA or their mix. Under operant-conditioning procedures, alcohol-drinking mice exhibited less MA reinforcement overall, than water controls. However, when drug availability was not behaviorally-contingent, alcohol-drinking mice consumed more MA and exhibited greater preference for the 10mg/L MA solution than drug-naïve and combination drug-experienced mice. Conversely, prior MA-drinking history increased alcohol intake across a range of alcohol concentrations. These exploratory studies indicate the feasibility of employing procedurally simple murine models of sequential and simultaneous oral MA-alcohol mixing of relevance to advancing our biobehavioral understanding of MA-alcohol co-abuse. Copyright © 2017 Elsevier B.V. All rights reserved.

Interprofessional mental health training in rural primary care: findings from a mixed methods study.

PubMed

Heath, Olga; Church, Elizabeth; Curran, Vernon; Hollett, Ann; Cornish, Peter; Callanan, Terrence; Bethune, Cheri; Younghusband, Lynda

2015-05-01

The benefits of interprofessional care in providing mental health services have been widely recognized, particularly in rural communities where access to health services is limited. There continues to be a need for more continuing interprofessional education in mental health intervention in rural areas. There have been few reports of rural programs in which mental health content has been combined with training in collaborative practice. The current study used a sequential mixed-method and quasi-experimental design to evaluate the impact of an interprofessional, intersectoral education program designed to enhance collaborative mental health capacity in six rural sites. Quantitative results reveal a significant increase in positive attitudes toward interprofessional mental health care teams and self-reported increases in knowledge and understanding about collaborative mental health care delivery. The analysis of qualitative data collected following completion of the program, reinforced the value of teaching mental health content within the context of collaborative practice and revealed practice changes, including more interprofessional and intersectoral collaboration. This study suggests that imbedding explicit training in collaborative care in content focused continuing professional education for more complex and chronic health issues may increase the likelihood that professionals will work together to effectively meet client needs.

Application of adobe flash media to optimize jigsaw learning model on geometry material

NASA Astrophysics Data System (ADS)

Imam, P.; Imam, S.; Ikrar, P.

2018-05-01

This study aims to determine and describe the effectiveness of the application of adobe flash media for jigsaw learning model on geometry material. In this study, the modified jigsaw learning with adobe flash media is called jigsaw-flash model. This research was conducted in Surakarta. The research method used is mix method research with exploratory sequential strategy. The results of this study indicate that students feel more comfortable and interested in studying geometry material taught by jigsaw-flash model. In addition, students taught using the jigsaw-flash model are more active and motivated than the students who were taught using ordinary jigsaw models. This shows that the use of the jigsaw-flash model can increase student participation and motivation. It can be concluded that the adobe flash media can be used as a solution to reduce the level of student abstraction in learning mathematics.

Coping and Its Relation to Retention among Male Minority Nursing Students in an Associate Degree Nursing Program in a South Texas Community College: An Explanatory Sequential Mixed Methods Inquiry

ERIC Educational Resources Information Center

Diggs, Gwendolyn Smith

2013-01-01

In Texas, there is an increase in the enrollment of men of various ethnicities in nursing schools, especially Associate Degree Nursing (ADN) programs. As these men strive to complete the nursing education, they face many concerns that center on barriers that are encountered in what is still a predominately Caucasian and female environment. In…

Analysis of membrane fusion as a two-state sequential process: evaluation of the stalk model.

PubMed

Weinreb, Gabriel; Lentz, Barry R

2007-06-01

We propose a model that accounts for the time courses of PEG-induced fusion of membrane vesicles of varying lipid compositions and sizes. The model assumes that fusion proceeds from an initial, aggregated vesicle state ((A) membrane contact) through two sequential intermediate states (I(1) and I(2)) and then on to a fusion pore state (FP). Using this model, we interpreted data on the fusion of seven different vesicle systems. We found that the initial aggregated state involved no lipid or content mixing but did produce leakage. The final state (FP) was not leaky. Lipid mixing normally dominated the first intermediate state (I(1)), but content mixing signal was also observed in this state for most systems. The second intermediate state (I(2)) exhibited both lipid and content mixing signals and leakage, and was sometimes the only leaky state. In some systems, the first and second intermediates were indistinguishable and converted directly to the FP state. Having also tested a parallel, two-intermediate model subject to different assumptions about the nature of the intermediates, we conclude that a sequential, two-intermediate model is the simplest model sufficient to describe PEG-mediated fusion in all vesicle systems studied. We conclude as well that a fusion intermediate "state" should not be thought of as a fixed structure (e.g., "stalk" or "transmembrane contact") of uniform properties. Rather, a fusion "state" describes an ensemble of similar structures that can have different mechanical properties. Thus, a "state" can have varying probabilities of having a given functional property such as content mixing, lipid mixing, or leakage. Our data show that the content mixing signal may occur through two processes, one correlated and one not correlated with leakage. Finally, we consider the implications of our results in terms of the "modified stalk" hypothesis for the mechanism of lipid pore formation. We conclude that our results not only support this hypothesis but also provide a means of analyzing fusion time courses so as to test it and gauge the mechanism of action of fusion proteins in the context of the lipidic hypothesis of fusion.

Evaluation of aroma enhancement for "Ecolly" dry white wines by mixed inoculation of selected Rhodotorula mucilaginosa and Saccharomyces cerevisiae.

PubMed

Wang, Xing-Chen; Li, Ai-Hua; Dizy, Marta; Ullah, Niamat; Sun, Wei-Xuan; Tao, Yong-Sheng

2017-08-01

To improve the aroma profile of Ecolly dry white wine, the simultaneous and sequential inoculations of selected Rhodotorula mucilaginosa and Saccharomyces cerevisiae were performed in wine making of this work. The two yeasts were mixed in various ratios for making the mixed inoculum. The amount of volatiles and aroma characteristics were determined the following year. Mixed fermentation improved both the varietal and fermentative aroma compound composition, especially that of (Z)-3-hexene-1-ol, nerol oxide, certain acetates and ethyls group compounds. Citrus, sweet fruit, acid fruit, berry, and floral aroma traits were enhanced by mixed fermentation; however, an animal note was introduced upon using higher amounts of R. mucilaginosa. Aroma traits were regressed with volatiles as observed by the partial least-square regression method. Analysis of correlation coefficients revealed that the aroma traits were the multiple interactions of volatile compounds, with the fermentative volatiles having more impact on aroma than varietal compounds. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sequential imaging of asymptomatic carotid atheroma using ultrasmall superparamagnetic iron oxide-enhanced magnetic resonance imaging: a feasibility study.

PubMed

Sadat, Umar; Howarth, Simon P S; Usman, Ammara; Tang, Tjun Y; Graves, Martin J; Gillard, Jonathan H

2013-11-01

Inflammation within atheromatous plaques is a known risk factor for plaque vulnerability. This can be detected in vivo on high-resolution magnetic resonance imaging (MRI) using ultrasmall superparamagnetic iron oxide (USPIO) contrast medium. The purpose of this study was to assess the feasibility of performing sequential USPIO studies over a 1-year period. Ten patients with moderate asymptomatic carotid stenosis underwent carotid MRI imaging both before and 36 hours after USPIO infusion at 0, 6, and 12 months. Images were manually segmented into quadrants, and the signal change per quadrant was calculated at these time points. A mixed repeated measures statistical model was used to determine signal change attributable to USPIO uptake over time. All patients remained asymptomatic during the study. The mixed model revealed no statistical difference in USPIO uptake between the 3 time points. Intraclass correlation coefficients revealed a good agreement of quadrant signal pre-USPIO infusion between 0 and 6 months (0.70) and 0 and 12 months (0.70). Good agreement of quadrant signal after USPIO infusion was shown between 0 and 6 months (0.68) and moderate agreement was shown between 0 and 12 months (0.33). USPIO-enhanced sequential MRI of atheromatous carotid plaques is clinically feasible. This may have important implications for future longitudinal studies involving pharmacologic intervention in large patient cohorts. Copyright © 2013 National Stroke Association. Published by Elsevier Inc. All rights reserved.

The effect of sequential exposure of color conditions on time and accuracy of graphic symbol location.

PubMed

Alant, Erna; Kolatsis, Anna; Lilienfeld, Margi

2010-03-01

An important aspect in AAC concerns the user's ability to locate an aided visual symbol on a communication display in order to facilitate meaningful interaction with partners. Recent studies have suggested that the use of different colored symbols may be influential in the visual search process, and that this, in turn will influence the speed and accuracy of symbol location. This study examined the role of color on rate and accuracy of identifying symbols on an 8-location overlay through the use of 3 color conditions (same, mixed and unique). Sixty typically developing preschool children were exposed to two different sequential exposures (Set 1 and Set 2). Participants searched for a target stimulus (either meaningful symbols or arbitrary forms) in a stimuli array. Findings indicated that the sequential exposures (orderings) impacted both time and accuracy for both types of symbols within specific instances.

Mobility and increased risk of HIV acquisition in South Africa: a mixed-method systematic review protocol.

PubMed

Dzomba, Armstrong; Govender, Kaymarlin; Mashamba-Thompson, Tivani P; Tanser, Frank

2018-02-27

In South Africa (home of the largest HIV epidemic globally), there are high levels of mobility. While studies produced in the recent past provide useful perspectives to the mobility-HIV risk linkage, systematic analyses are needed for in-depth understanding of the complex dynamics between mobility and HIV risk. We plan to undertake an evidence-based review of existing literature connecting mobility and increased risky sexual behavior as well as risk of HIV acquisition in South Africa. We will conduct a mixed-method systematic review of peer-reviewed studies published between 2000 and 2015. In particular, we will search for relevant South African studies from the following databases: MEDLINE, EMBASE, Web of Science, and J-STOR databases. Studies explicitly examining HIV and labor migration will be eligible for inclusion, while non-empirical work and other studies on key vulnerable populations such as commercial sex workers (CSW) and men who have sex with men (MSM) will be excluded. The proposed mixed-method systematic review will employ a three-phase sequential approach [i.e., (i) identifying relevant studies through data extraction (validated by use of Distiller-SR data management software), (ii) qualitative synthesis, and (iii) quantitative synthesis including meta-analysis data]. Recurrent ideas and conclusions from syntheses will be compiled into key themes and further processed into categories and sub-themes constituting the primary and secondary outcomes of this study. Synthesis of main findings from different studies examining the subject issue here may uncover important research gaps in this literature, laying a strong foundation for research and development of sustainable localized migrant-specific HIV prevention strategies in South Africa. Our protocol was registered with PROSPERO under registration number: CRD 42017055580. ( https://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42017055580 ).

Characterizing the structure and content of nurse handoffs: A Sequential Conversational Analysis approach.

PubMed

Abraham, Joanna; Kannampallil, Thomas; Brenner, Corinne; Lopez, Karen D; Almoosa, Khalid F; Patel, Bela; Patel, Vimla L

2016-02-01

Effective communication during nurse handoffs is instrumental in ensuring safe and quality patient care. Much of the prior research on nurse handoffs has utilized retrospective methods such as interviews, surveys and questionnaires. While extremely useful, an in-depth understanding of the structure and content of conversations, and the inherent relationships within the content is paramount to designing effective nurse handoff interventions. In this paper, we present a methodological framework-Sequential Conversational Analysis (SCA)-a mixed-method approach that integrates qualitative conversational analysis with quantitative sequential pattern analysis. We describe the SCA approach and provide a detailed example as a proof of concept of its use for the analysis of nurse handoff communication in a medical intensive care unit. This novel approach allows us to characterize the conversational structure, clinical content, disruptions in the conversation, and the inherently phasic nature of nurse handoff communication. The characterization of communication patterns highlights the relationships underlying the verbal content of nurse handoffs with specific emphasis on: the interactive nature of conversation, relevance of role-based (incoming, outgoing) communication requirements, clinical content focus on critical patient-related events, and discussion of pending patient management tasks. We also discuss the applicability of the SCA approach as a method for providing in-depth understanding of the dynamics of communication in other settings and domains. Copyright © 2015 Elsevier Inc. All rights reserved.

The effectiveness of a preferred intensity exercise programme on the mental health outcomes of young people with depression: a sequential mixed methods evaluation.

PubMed

Carter, Tim; Callaghan, Patrick; Khalil, Elizabeth; Morres, Ioannis

2012-03-13

People with mental illness are more likely to suffer physical health problems than comparable populations who do not have mental illness. There is evidence to suggest that exercise, as well has having obvious physical benefits, also has positive effects on mental health. There is a distinct paucity of research testing its effects on young people seeking help for mental health issues. Additionally, it is generally found that compliance with prescribed exercise programmes is low. As such, encouraging young people to exercise at levels recommended by national guidelines may be unrealistic considering their struggle with mental health difficulties. It is proposed that an exercise intervention tailored to young people's preferred intensity may improve mental health outcomes, overall quality of life, and reduce exercise attrition rates. A sequential mixed methods design will be utilised to assess the effectiveness of an individually tailored exercise programme on the mental health outcomes of young people with depression. The mixed methods design incorporates a Randomised Controlled Trial (RCT), focus groups and interviews and an economic evaluation. 158 young people (14-17 years) recruited from primary care and voluntary services randomly allocated to either the intervention group or control group. Intervention group: PARTICIPANTS will undertake a 12 week exercise programme of 12 × 60 minutes of preferred intensity aerobic exercise receiving motivational coaching and support throughout. PARTICIPANTS will also be invited to attend focus groups and 1-1 interviews following completion of the exercise programme to illicit potential barriers facilitators to participation. PARTICIPANTS will receive treatment as usual. Depression using the Children's Depression Inventory 2 (CDI-2). Quality of Life (EQ-5D), physical fitness (Borg RPE scale, heart rate), incidents of self-harm, treatment received and compliance with treatment, and the cost effectiveness of the intervention. Outcome measures will be taken at baseline, post intervention and 6 month follow up. The results of this study will inform policy makers of the effectiveness of preferred intensity exercise on the mental health outcomes of young people with depression, the acceptability of such an intervention to this population and its cost effectiveness. ClinicalTrials.gov: NCT01474837.

The application of intraoperative transit time flow measurement to accurately assess anastomotic quality in sequential vein grafting

PubMed Central

Yu, Yang; Zhang, Fan; Gao, Ming-Xin; Li, Hai-Tao; Li, Jing-Xing; Song, Wei; Huang, Xin-Sheng; Gu, Cheng-Xiong

2013-01-01

OBJECTIVES Intraoperative transit time flow measurement (TTFM) is widely used to assess anastomotic quality in coronary artery bypass grafting (CABG). However, in sequential vein grafting, the flow characteristics collected by the conventional TTFM method are usually associated with total graft flow and might not accurately indicate the quality of every distal anastomosis in a sequential graft. The purpose of our study was to examine a new TTFM method that could assess the quality of each distal anastomosis in a sequential graft more reliably than the conventional TTFM approach. METHODS Two TTFM methods were tested in 84 patients who underwent sequential saphenous off-pump CABG in Beijing An Zhen Hospital between April and August 2012. In the conventional TTFM method, normal blood flow in the sequential graft was maintained during the measurement, and the flow probe was placed a few centimetres above the anastomosis to be evaluated. In the new method, blood flow in the sequential graft was temporarily reduced during the measurement by placing an atraumatic bulldog clamp at the graft a few centimetres distal to the anastomosis to be evaluated, while the position of the flow probe remained the same as in the conventional method. This new TTFM method was named the flow reduction TTFM. Graft flow parameters measured by both methods were compared. RESULTS Compared with the conventional TTFM, the flow reduction TTFM resulted in significantly lower mean graft blood flow (P < 0.05); in contrast, yielded significantly higher pulsatility index (P < 0.05). Diastolic filling was not significantly different between the two methods and was >50% in both cases. Interestingly, the flow reduction TTFM identified two defective middle distal anastomoses that the conventional TTFM failed to detect. Graft flows near the defective distal anastomoses were improved substantially after revision. CONCLUSIONS In this study, we found that temporary reduction of graft flow during TTFM seemed to enhance the sensitivity of TTFM to less-than-critical anastomotic defects in a sequential graft and to improve the overall accuracy of the intraoperative assessment of anastomotic quality in sequential vein grafting. PMID:24000314

Sequential Anaerobic/Aerobic Digestion for Enhanced Carbon/Nitrogen Removal and Cake Odor Reduction.

PubMed

Ahmad, Muneer; Denee, Marco Abel; Jiang, Hao; Eskicioglu, Cigdem; Kadota, Paul; Gregonia, Theresa

2016-12-01

  Anaerobic digestion (AD) has been proven to be an effective process for the treatment of wastewater sludge. However, it produces high levels of ammonia in the digester effluent, which may jeopardize meeting stringent nutrient discharge limits. In this study, the effect of a sequential anaerobic/aerobic (AN/AERO) digestion and a single-stage conventional AN digestion (as control) was investigated on mixed (primary + secondary) sludge generated by the Annacis Island wastewater treatment plant (WWTP) (BC, Canada). An overall sludge retention time (SRT) of 22.5 days under three different scenarios was chosen based on the current operational SRT of the digesters at the Annacis Island WWTP. The steady state results have shown that sequential AN/AERO digestion configurations achieved up to 11% higher volatile solids (VS) removal and 72% lower ammonia generation over single-stage conventional AN digestion. Furthermore, sequential AN/AERO system also showed enhanced dewaterability, improved fecal coliform destruction and reduced digested cake odors over control digesters.

[A novel M142T mutation in the B glycosyltransferase gene associated with B3 variant in Chinese].

PubMed

Xu, Xian-guo; Hong, Xiao-zhen; Liu, Ying; Zhu, Fa-ming; Lv, Hang-jun; Yan, Li-xing

2009-06-01

To investigate the molecular genetic basis of the B3 variant of ABO blood group system with mixed-field hemagglutination in Chinese. Serological techniques were performed to characterize the erythrocyte phenotype of two discrepant samples. A sequential agglutination method and 13 short tandem repeat (STR) loci were tested to exclude the possibility of exogenous or endogenous DNA chimera. Mutations in exons 6 and 7, including partial intron of the ABO gene, were screened by polymerase chain reaction and DNA sequencing. Haplotypes of the two individuals were also analyzed by sequencing. A mixed-field hemagglutination of RBCs with anti-B and anti-AB antibodies was detected in the two unrelated individuals. Exogenous ABO-incompatible RBC transfusion and endogenous genetic chimera were excluded by sequential agglutination method and STR. The ABO phenotypes of the two individuals were classified as A1B3 according to the ABO subgroup definition. The sequence region from intron 5 to 3'-UTR of the B allele was identical to that of ABO*B101 allele, except for a T to C substitution at nucleotide position 425 in exon 7. This substitution resulted in an amino acid change of M142T in the B glycosyltransferase. A novel B allele with 425T>C substitution resulting in B3 subgroup was identified in two Chinese individuals.

A Simple Automated Method for the Determination of Nitrate and Nitrite in Infant Formula and Milk Powder Using Sequential Injection Analysis

PubMed Central

Pistón, Mariela; Mollo, Alicia; Knochen, Moisés

2011-01-01

A fast and efficient automated method using a sequential injection analysis (SIA) system, based on the Griess, reaction was developed for the determination of nitrate and nitrite in infant formulas and milk powder. The system enables to mix a measured amount of sample (previously constituted in the liquid form and deproteinized) with the chromogenic reagent to produce a colored substance whose absorbance was recorded. For nitrate determination, an on-line prereduction step was added by passing the sample through a Cd minicolumn. The system was controlled from a PC by means of a user-friendly program. Figures of merit include linearity (r2 > 0.999 for both analytes), limits of detection (0.32 mg kg−1 NO3-N, and 0.05 mg kg−1 NO2-N), and precision (sr%) 0.8–3.0. Results were statistically in good agreement with those obtained with the reference ISO-IDF method. The sampling frequency was 30 hour−1 (nitrate) and 80 hour−1 (nitrite) when performed separately. PMID:21960750

Enhanced 3-Sulfanylhexan-1-ol Production in Sequential Mixed Fermentation with Torulaspora delbrueckii/Saccharomyces cerevisiae Reveals a Situation of Synergistic Interaction between Two Industrial Strains

PubMed Central

Renault, Philippe; Coulon, Joana; Moine, Virginie; Thibon, Cécile; Bely, Marina

2016-01-01

The aim of this work was to study the volatile thiol productions of two industrial strains of Torulaspora delbrueckii and Saccharomyces cerevisiae during alcoholic fermentation (AF) of Sauvignon Blanc must. In order to evaluate the influence of the inoculation procedure, sequential and simultaneous mixed cultures were carried out and compared to pure cultures of T. delbrueckii and S. cerevisiae. The results confirmed the inability of T. delbrueckii to release 4-methyl-4-sulfanylpentan-2-one (4MSP) and its low capacity to produce 3-sulfanylhexyl acetate (3SHA), as already reported in previous studies. A synergistic interaction was observed between the two species, resulting in higher levels of 3SH (3-sulfanylhexan-1-ol) and its acetate when S. cerevisiae was inoculated 24 h after T. delbrueckii, compared to the pure cultures. To elucidate the nature of the interactions between these two species, the yeast population kinetics were examined and monitored, as well as the production of 3SH, its acetate and their related non-odorous precursors: Glut-3SH (glutathionylated conjugate precursor) and Cys-3SH (cysteinylated conjugate precursor). For the first time, it was suggested that, unlike S. cerevisiae, which is able to metabolize the two precursor forms, T. delbrueckii was only able to metabolize the glutathionylated precursor. Consequently, the presence of T. delbrueckii during mixed fermentation led to an increase in Glut-3SH degradation and Cys-3SH production. This overproduction was dependent on the T. delbrueckii biomass. In sequential culture, thus favoring T. delbrueckii development, the higher availability of Cys-3SH throughout AF resulted in more abundant 3SH and 3SHA production by S. cerevisiae. PMID:27014216

Enhanced 3-Sulfanylhexan-1-ol Production in Sequential Mixed Fermentation with Torulaspora delbrueckii/Saccharomyces cerevisiae Reveals a Situation of Synergistic Interaction between Two Industrial Strains.

PubMed

Renault, Philippe; Coulon, Joana; Moine, Virginie; Thibon, Cécile; Bely, Marina

2016-01-01

The aim of this work was to study the volatile thiol productions of two industrial strains of Torulaspora delbrueckii and Saccharomyces cerevisiae during alcoholic fermentation (AF) of Sauvignon Blanc must. In order to evaluate the influence of the inoculation procedure, sequential and simultaneous mixed cultures were carried out and compared to pure cultures of T. delbrueckii and S. cerevisiae. The results confirmed the inability of T. delbrueckii to release 4-methyl-4-sulfanylpentan-2-one (4MSP) and its low capacity to produce 3-sulfanylhexyl acetate (3SHA), as already reported in previous studies. A synergistic interaction was observed between the two species, resulting in higher levels of 3SH (3-sulfanylhexan-1-ol) and its acetate when S. cerevisiae was inoculated 24 h after T. delbrueckii, compared to the pure cultures. To elucidate the nature of the interactions between these two species, the yeast population kinetics were examined and monitored, as well as the production of 3SH, its acetate and their related non-odorous precursors: Glut-3SH (glutathionylated conjugate precursor) and Cys-3SH (cysteinylated conjugate precursor). For the first time, it was suggested that, unlike S. cerevisiae, which is able to metabolize the two precursor forms, T. delbrueckii was only able to metabolize the glutathionylated precursor. Consequently, the presence of T. delbrueckii during mixed fermentation led to an increase in Glut-3SH degradation and Cys-3SH production. This overproduction was dependent on the T. delbrueckii biomass. In sequential culture, thus favoring T. delbrueckii development, the higher availability of Cys-3SH throughout AF resulted in more abundant 3SH and 3SHA production by S. cerevisiae.

A path-level exact parallelization strategy for sequential simulation

NASA Astrophysics Data System (ADS)

Peredo, Oscar F.; Baeza, Daniel; Ortiz, Julián M.; Herrero, José R.

2018-01-01

Sequential Simulation is a well known method in geostatistical modelling. Following the Bayesian approach for simulation of conditionally dependent random events, Sequential Indicator Simulation (SIS) method draws simulated values for K categories (categorical case) or classes defined by K different thresholds (continuous case). Similarly, Sequential Gaussian Simulation (SGS) method draws simulated values from a multivariate Gaussian field. In this work, a path-level approach to parallelize SIS and SGS methods is presented. A first stage of re-arrangement of the simulation path is performed, followed by a second stage of parallel simulation for non-conflicting nodes. A key advantage of the proposed parallelization method is to generate identical realizations as with the original non-parallelized methods. Case studies are presented using two sequential simulation codes from GSLIB: SISIM and SGSIM. Execution time and speedup results are shown for large-scale domains, with many categories and maximum kriging neighbours in each case, achieving high speedup results in the best scenarios using 16 threads of execution in a single machine.

The Development of Auditory Sequential Memory in Young Black and White Children.

ERIC Educational Resources Information Center

Hurley, Oliver L.; And Others

The question of whether Black children "peak" earlier than White children in auditory sequential memory (ASM) was investigated in 122 Black children and 120 White children in grades k-3 in two racially mixed schools in a large southern community. Each S was given the ASM subtest of the Illinois Test of Psycholinguistic Abilities. Results…

Increase of fruity aroma during mixed T. delbrueckii/S. cerevisiae wine fermentation is linked to specific esters enhancement.

PubMed

Renault, Philippe; Coulon, Joana; de Revel, Gilles; Barbe, Jean-Christophe; Bely, Marina

2015-08-17

The aim of this work was to study ester formation and the aromatic impact of Torulaspora delbrueckii when used in association with Saccharomyces cerevisiae during the alcoholic fermentation of must. In order to evaluate the influence of the inoculation procedure, sequential and simultaneous mixed cultures were carried out and compared to pure cultures of T. delbrueckii and S. cerevisiae. Our results showed that mixed inoculations allowed the increase, in comparison to S. cerevisiae pure culture, of some esters specifically produced by T. delbrueckii and significantly correlated to the maximal T. delbrueckii population reached in mixed cultures. Thus, ethyl propanoate, ethyl isobutanoate and ethyl dihydrocinnamate were considered as activity markers of T. delbrueckii. On the other hand, isobutyl acetate and isoamyl acetate concentrations were systematically increased during mixed inoculations although not correlated with the development of either species but were rather due to positive interactions between these species. Favoring T. delbrueckii development when performing sequential inoculation enhanced the concentration of esters linked to T. delbrueckii activity. On the contrary, simultaneous inoculation restricted the growth of T. delbrueckii, limiting the production of its activity markers, but involved a very important production of numerous esters due to more important positive interactions between species. These results suggest that the ester concentrations enhancement via interactions during mixed modalities was due to S. cerevisiae production in response to the presence of T. delbrueckii. Finally, sensory analyses showed that mixed inoculations between T. delbrueckii and S. cerevisiae allowed to enhance the complexity and fruity notes of wine in comparison to S. cerevisiae pure culture. Furthermore, the higher levels of ethyl propanoate, ethyl isobutanoate, ethyl dihydrocinnamate and isobutyl acetate in mixed wines were found responsible for the increase of fruitiness and complexity. Copyright © 2015 Elsevier B.V. All rights reserved.

Pilot Testing of the NURSE Stress Management Intervention.

PubMed

Delaney, Colleen; Barrere, Cynthia; Robertson, Sue; Zahourek, Rothlyn; Diaz, Desiree; Lachapelle, Leeanne

2016-12-01

Student nurses experience significant stress during their education, which may contribute to illness and alterations in health, poor academic performance, and program attrition. The aim of this pilot study was to evaluate the feasibility and potential efficacy of an innovative stress management program in two baccalaureate nursing programs in Connecticut, named NURSE (Nurture nurse, Use resources, foster Resilience, Stress and Environment management), that assists nursing students to develop stress management plans. An explanatory sequential mixed-methods design was used to evaluate the effects of the intervention with 40 junior nursing students. Results from this study provide evidence that the NURSE intervention is highly feasible, and support further testing to examine the effect of the intervention in improving stress management in nursing students. © The Author(s) 2015.

Building Level Administrators' Attitudes toward Teacher Effectiveness at the High School and Middle School Levels

ERIC Educational Resources Information Center

Hanson, Nathan K.

2010-01-01

This study investigated the attitudes of administrators about differences and similarities between middle and high school teachers. The research question that guided the study was, "Do attitudes about what makes an effective educator differ between building administrators at the middle and high school levels?" A formal, sequential, mixed-methods…

Using a mixed methods research design to investigate complementary alternative medicine (CAM) use among women with breast cancer in Ireland.

PubMed

Fox, Patricia; Butler, Michelle; Coughlan, Barbara; Murray, Mary; Boland, Noreen; Hanan, Terry; Murphy, Hilary; Forrester, Pauline; O' Brien, Marie; O' Sullivan, Nollaig

2013-08-01

To investigate complementary and alternative medicine (CAM) use among women with breast cancer in Ireland using a mixed methods modified sequential explanatory design. Semi-structured interviews were conducted with oncology professionals (n = 20) and CAM practitioners (n = 20) and this was followed by a survey of 406 women with breast cancer using the 'Use of Complementary and Alternative Therapies Survey' questionnaire (UCATS) (Lengacher et al., 2003). Follow up interviews were subsequently undertaken with a subset of this survey sample (n = 31). Over half of those surveyed (55.7%, n = 226) used some form of CAM since diagnosis. The most frequently used therapies were massage, herbal supplements (including herbs with oestrogenic properties), antioxidants, relaxation, counselling, health supplements, reflexology, reiki and support groups. Dietary interventions were used primarily to reduce symptoms and/or side effects while reduction of psychological stress was the primary reason for use of stress-reducing therapies. Most respondents reported that the CAM therapies they had used were helpful. The qualitative data elaborated on and provided clarification of the survey results. Similar to international studies, CAM is popular among women with breast cancer in Ireland. As such, the challenge for Irish oncology professionals is to identify low risk CAM therapies that are likely to benefit patients while educating patients and themselves on therapies which may be of concern. This study clearly illustrates the benefits of using a mixed methods approach to enhance our understanding of a complex clinical issue and thus we recommend that this method should be the method of choice when planning health services research. Copyright © 2012 Elsevier Ltd. All rights reserved.

Effect of chemical and physical heterogeneities on colloid-facilitated cesium transport

NASA Astrophysics Data System (ADS)

Rod, Kenton; Um, Wooyong; Chun, Jaehun; Wu, Ning; Yin, Xialong; Wang, Guohui; Neeves, Keith

2018-06-01

A set of column experiments was conducted to investigate the chemical and physical heterogeneity effect on colloid facilitated transport under slow pore velocity conditions. Pore velocities were kept below 100 cm d-1 for all experiments. Glass beads were packed into columns establishing four different conditions: 1) homogeneous, 2) mixed physical heterogeneity, 3) sequentially layered physical heterogeneity, and 4) chemical heterogeneity. The homogeneous column was packed with glass beads (diameter 500-600 μm), and physical heterogeneities were created by sequential layering or mixing two sizes of glass bead (500-600 μm and 300-400 μm). A chemical heterogeneity was created using 25% of the glass beads coated with hydrophobic molecules (1H-1H-2H-2H-perfluorooctyltrichlorosilane) mixed with 75% pristine glass beads (all 500-600 μm). Input solution with 0.5 mM CsI and 50 mg L-1 colloids (1-μm diameter SiO2) was pulsed into columns under saturated conditions. The physical heterogeneity in the packed glass beads retarded the transport of colloids compared to homogeneous (R = 25.0), but showed only slight differences between sequentially layered (R = 60.7) and mixed heterogeneity(R = 62.4). The column with the chemical, hydrophobic/hydrophilic, heterogeneity removed most of the colloids from the input solution. All column conditions stripped Cs from colloids onto the column matrix of packed glass beads.

Self assembly of oppositely charged latex particles at oil-water interface.

PubMed

Nallamilli, Trivikram; Ragothaman, Srikanth; Basavaraj, Madivala G

2017-01-15

In this study we explore the self assembly of oppositely charged latex particles at decane water interfaces. Two spreading protocols have been proposed in this context. In the first method oppositely charged particles are mixed prior to spreading at the interface, this is called "premixed-mixtures". In the second protocol negatively charged particles are first spread at the interface at known coverage followed by spreading positively charged particles at known coverage and this is called "sequential-mixtures". In premixed mixtures depending on particle mixing ratio (composition) and total surface coverage a number of 2d structures ranging from 2d crystals, aggregate-crystal coexistence and 2d-gels are observed. A detailed phase diagram of this system has been explored. In sequential-mixtures for the first time we observed a new phase in colloidal monolayers called 2d-bi crystalline domains. These structures consisted regions of two crystal phases of oppositely charged particles separated by a one dimensional chain of alternating positive and negative particles. Phase diagram of this system has also been explored at various combinations of first spread and second spread particles. A possible mechanism leading to formation of these 2d bi crystalline structures has been discussed. A direct visualization of breakage and reformation of particle barriers separating the crystal phases has been demonstrated through videos. Effect of salt in the water sub phase and particle hydrophobicity on domain formation is also investigated. Copyright © 2016 Elsevier Inc. All rights reserved.

Applying Sparse Machine Learning Methods to Twitter: Analysis of the 2012 Change in Pap Smear Guidelines. A Sequential Mixed-Methods Study

PubMed Central

Godbehere, Andrew; Le, Gem; El Ghaoui, Laurent; Sarkar, Urmimala

2016-01-01

Background It is difficult to synthesize the vast amount of textual data available from social media websites. Capturing real-world discussions via social media could provide insights into individuals’ opinions and the decision-making process. Objective We conducted a sequential mixed methods study to determine the utility of sparse machine learning techniques in summarizing Twitter dialogues. We chose a narrowly defined topic for this approach: cervical cancer discussions over a 6-month time period surrounding a change in Pap smear screening guidelines. Methods We applied statistical methodologies, known as sparse machine learning algorithms, to summarize Twitter messages about cervical cancer before and after the 2012 change in Pap smear screening guidelines by the US Preventive Services Task Force (USPSTF). All messages containing the search terms “cervical cancer,” “Pap smear,” and “Pap test” were analyzed during: (1) January 1–March 13, 2012, and (2) March 14–June 30, 2012. Topic modeling was used to discern the most common topics from each time period, and determine the singular value criterion for each topic. The results were then qualitatively coded from top 10 relevant topics to determine the efficiency of clustering method in grouping distinct ideas, and how the discussion differed before vs. after the change in guidelines . Results This machine learning method was effective in grouping the relevant discussion topics about cervical cancer during the respective time periods (~20% overall irrelevant content in both time periods). Qualitative analysis determined that a significant portion of the top discussion topics in the second time period directly reflected the USPSTF guideline change (eg, “New Screening Guidelines for Cervical Cancer”), and many topics in both time periods were addressing basic screening promotion and education (eg, “It is Cervical Cancer Awareness Month! Click the link to see where you can receive a free or low cost Pap test.”) Conclusions It was demonstrated that machine learning tools can be useful in cervical cancer prevention and screening discussions on Twitter. This method allowed us to prove that there is publicly available significant information about cervical cancer screening on social media sites. Moreover, we observed a direct impact of the guideline change within the Twitter messages. PMID:27288093

Creating Advantages with Franchising in Healthcare: An Explorative Mixed Methods Study on the Role of the Relationship between the Franchisor and Units

PubMed Central

Nijmeijer, Karlijn Jojanneke; Fabbricotti, Isabelle Natalina; Huijsman, Robbert

2015-01-01

Background Franchising is a promising and increasingly used organizational form to improve strategic, organizational, professional and client-related results in healthcare. However, evidence is scarce regarding how franchises should be operated to actualize such results. This paper aimed to explore the association between the results achieved by healthcare franchises and the working relationships among actors in these franchises. Methods A sequential mixed methods approach was used to obtain both in-depth and broader quantifiable insights into a little-investigated phenomenon. We first employed a qualitative multiple embedded case study. Data were collected through observations, document analyses, and 96 in-depth semi-structured interviews in three Dutch healthcare franchises. Within-case and cross-case comparative analyses were conducted. Subsequently, a cross-sectional survey was developed based on the qualitative study and disseminated among 19 healthcare franchises. 40 franchisors and 346 unit actors filled in the questionnaire. Findings It seems important to have open, committed, cooperative franchise relationships in which professional franchisees and unit managers feel and trust that they have the opportunity to introduce ideas and articulate their needs to the franchisor. Such relationships help ensure satisfaction, survival, and quality of care, because they serve to foster synergy realization and local fit and prevent reinventing the wheel and professional resistance. PMID:25664581

Cochrane Qualitative and Implementation Methods Group guidance series-paper 5: methods for integrating qualitative and implementation evidence within intervention effectiveness reviews.

PubMed

Harden, Angela; Thomas, James; Cargo, Margaret; Harris, Janet; Pantoja, Tomas; Flemming, Kate; Booth, Andrew; Garside, Ruth; Hannes, Karin; Noyes, Jane

2018-05-01

The Cochrane Qualitative and Implementation Methods Group develops and publishes guidance on the synthesis of qualitative and mixed-method evidence from process evaluations. Despite a proliferation of methods for the synthesis of qualitative research, less attention has focused on how to integrate these syntheses within intervention effectiveness reviews. In this article, we report updated guidance from the group on approaches, methods, and tools, which can be used to integrate the findings from quantitative studies evaluating intervention effectiveness with those from qualitative studies and process evaluations. We draw on conceptual analyses of mixed methods systematic review designs and the range of methods and tools that have been used in published reviews that have successfully integrated different types of evidence. We outline five key methods and tools as devices for integration which vary in terms of the levels at which integration takes place; the specialist skills and expertise required within the review team; and their appropriateness in the context of limited evidence. In situations where the requirement is the integration of qualitative and process evidence within intervention effectiveness reviews, we recommend the use of a sequential approach. Here, evidence from each tradition is synthesized separately using methods consistent with each tradition before integration takes place using a common framework. Reviews which integrate qualitative and process evaluation evidence alongside quantitative evidence on intervention effectiveness in a systematic way are rare. This guidance aims to support review teams to achieve integration and we encourage further development through reflection and formal testing. Copyright © 2017 Elsevier Inc. All rights reserved.

An exploration of men's experiences of undergoing active surveillance for favourable-risk prostate cancer: A mixed methods study protocol.

PubMed

Ruane-McAteer, Eimear; O'Sullivan, Joe; Porter, Sam; Venderbos, Lionne; Prue, Gillian

2016-08-02

Prostate cancer is one of the most common male cancers worldwide. Active Surveillance (AS) has been developed to allow men with lower risk disease to postpone or avoid the adverse side effects associated with curative treatments until the disease progresses. Despite the medical benefits of AS, it is reported that living with untreated cancer can create a significant emotional burden for patients. The aim of this study is to gain insight into the experiences of men eligible to undergo AS for favourable-risk PCa. This study has a mixed-methods sequential explanatory design consisting of two phases: quantitative followed by qualitative. Phase 1 has a multiple point, prospective, longitudinal exploratory design. Ninety men diagnosed with favourable-risk prostate cancer will be assessed immediately post-diagnosis (baseline) and followed over a period of 12 months, in intervals of 3 month. Ninety age-matched men with no cancer diagnosis will also be recruited using peer nomination and followed up in the same 3 month intervals. Following completion of Phase 1, 10-15 AS participants who have reported both the best and worst psychological functioning will be invited to participate in semi-structured qualitative interviews. Phase 2 will facilitate further exploration of the quantitative results and obtain a richer understanding of participants' personal interpretations of their illness and psychological wellbeing. To our knowledge, this is the first study to utilise early baseline measures; include a healthy comparison group; calculate sample size through power calculations; and use a mixed methods approach to gain a deeper more holistic insight into the experiences of men diagnosed with favourable-risk prostate cancer.

Creating advantages with franchising in healthcare: an explorative mixed methods study on the role of the relationship between the franchisor and units.

PubMed

Nijmeijer, Karlijn Jojanneke; Fabbricotti, Isabelle Natalina; Huijsman, Robbert

2015-01-01

Franchising is a promising and increasingly used organizational form to improve strategic, organizational, professional and client-related results in healthcare. However, evidence is scarce regarding how franchises should be operated to actualize such results. This paper aimed to explore the association between the results achieved by healthcare franchises and the working relationships among actors in these franchises. A sequential mixed methods approach was used to obtain both in-depth and broader quantifiable insights into a little-investigated phenomenon. We first employed a qualitative multiple embedded case study. Data were collected through observations, document analyses, and 96 in-depth semi-structured interviews in three Dutch healthcare franchises. Within-case and cross-case comparative analyses were conducted. Subsequently, a cross-sectional survey was developed based on the qualitative study and disseminated among 19 healthcare franchises. 40 franchisors and 346 unit actors filled in the questionnaire. It seems important to have open, committed, cooperative franchise relationships in which professional franchisees and unit managers feel and trust that they have the opportunity to introduce ideas and articulate their needs to the franchisor. Such relationships help ensure satisfaction, survival, and quality of care, because they serve to foster synergy realization and local fit and prevent reinventing the wheel and professional resistance.

Exploring breast cancer preventive lifestyle and social support of Iranian women: a study protocol for a mixed-methods approach.

PubMed

Khazaee-Pool, Maryam; Pashaei, Tahereh; Jahangiry, Leila; Ponnet, Koen; Gholami, Ali

2017-06-07

It is widely accepted that a healthy lifestyle may decrease the probability of developing cancer. This study aimed to describe a study protocol that makes it possible to explore preventive health lifestyles of Iranian women and their received social support for the purpose of developing cultural strategies to increase breast cancer prevention. A mixed-methods study will be accomplished in two sequential parts. First, a cross-sectional study will be conducted in which 2,250 Iranian women are recruited by using a random multistage cluster sampling of 20 health care centers. Structured face-to-face interviews will be conducted to obtain information on the participants' health lifestyle and perceived social support. Data will be analyzed using both multivariate regression and structural equation modeling techniques. Then, a qualitative study will be conducted among employed women using a purposive sampling design. Data will be collected by means of focus groups and semi-structured interviews and will be analyzed using a conventional content analysis approach. The results of the quantitative and qualitative study will be used to develop breast cancer preventive strategies. Researchers need to acquire knowledge regarding the lifestyle and perceived social support of Iranian women that will foster culturally competent approaches to promote healthy lifestyles to develop breast cancer preventive strategies. Examining breast cancer preventive lifestyles provides valuable information for designing applicable intervention programs for improving women's health.

Firefighter willingness to participate in a stem cell clinical trial for burns: A mixed methods study.

PubMed

Horch, Jenny D; Carr, Eloise C J; Harasym, Patricia; Burnett, Lindsay; Biernaskie, Jeff; Gabriel, Vincent

2016-12-01

Adult stem cells represent a potentially renewable and autologous source of cells to regenerate skin and improve wound healing. Firefighters are at risk of sustaining a burn and potentially benefiting from a split thickness skin graft (STSG). This mixed methods study examined firefighter willingness to participate in a future stem cell clinical trial, outcome priorities and factors associated with this decision. A sequential explanatory mixed methods design was used. The quantitative phase (online questionnaire) was followed by the qualitative phase (semi-structured interviews). A sample of 149 firefighters completed the online survey, and a purposeful sample of 15 firefighters was interviewed. A majority (74%) reported they would participate in a future stem cell clinical trial if they experienced burn benefiting from STSG. Hypothetical concerns related to receiving a STSG were pain, itch, scarring/redness and skin durability. Participants indicated willingness to undergo stem cell therapy if the risk of no improvement was 43% or less. Risk tolerance was predicted by perceived social support and having children. Interviews revealed four main themes: a desire to help others, improving clinical outcomes, trusting relationships, and a belief in scientific investigation. Many participants admitted lacking sufficient knowledge to make an informed decision regarding stem cell therapies. Firefighters indicated they were largely willing to participate in a stem cell clinical trial but also indicated a lack of knowledge upon which to make a decision. Public education of the role of stem cells in STSG will be increasingly important as clinical trials are developed. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

Practice-induced and sequential modulations of the Simon effect.

PubMed

Soetens, Eric; Maetens, Kathleen; Zeischka, Peter

2010-05-01

People react more quickly and more accurately to stimuli presented in locations corresponding to the response, as compared with noncorresponding locations, even when stimulus location is irrelevant (Simon effect [SE]). The explanation that SEs are caused by the automatic priming of a corresponding response has been questioned, because of the many exceptions to the effect. We replicated practice-induced and sequential modulations of the SE in two experiments--first, by training participants with blocks of location-relevant stimuli, and second, by mixing location-relevant and location-irrelevant trials. The decrease of the SE with incompatible training was relatively permanent in the blocked experiment, whereas the effect was temporary in the mixed experiment. The difference was caused by a more permanent reversal of the SE after incongruent trials, showing that sequential modulations depend on long-term practice effects. We suggest that there is a formation of a contralateral long-term memory stimulus-response link in blocked conditions and that short-term and long-term memory links are primed by preceding events.

The Oenological Potential of Hanseniaspora uvarum in Simultaneous and Sequential Co-fermentation with Saccharomyces cerevisiae for Industrial Wine Production

PubMed Central

Tristezza, Mariana; Tufariello, Maria; Capozzi, Vittorio; Spano, Giuseppe; Mita, Giovanni; Grieco, Francesco

2016-01-01

In oenology, the utilization of mixed starter cultures composed by Saccharomyces and non-Saccharomyces yeasts is an approach of growing importance for winemakers in order to enhance sensory quality and complexity of the final product without compromising the general quality and safety of the oenological products. In fact, several non-Saccharomyces yeasts are already commercialized as oenological starter cultures to be used in combination with Saccharomyces cerevisiae, while several others are the subject of various studies to evaluate their application. Our aim, in this study was to assess, for the first time, the oenological potential of H. uvarum in mixed cultures (co-inoculation) and sequential inoculation with S. cerevisiae for industrial wine production. Three previously characterized H. uvarum strains were separately used as multi-starter together with an autochthonous S. cerevisiae starter culture in lab-scale micro-vinification trials. On the basis of microbial development, fermentation kinetics and secondary compounds formation, the strain H. uvarum ITEM8795 was further selected and it was co- and sequentially inoculated, jointly with the S. cerevisiae starter, in a pilot scale wine production. The fermentation course and the quality of final product indicated that the co-inoculation was the better performing modality of inoculum. The above results were finally validated by performing an industrial scale vinification The mixed starter was able to successfully dominate the different stages of the fermentation process and the H. uvarum strain ITEM8795 contributed to increasing the wine organoleptic quality and to simultaneously reduce the volatile acidity. At the best of our knowledge, the present report is the first study regarding the utilization of a selected H. uvarum strain in multi-starter inoculation with S. cerevisiae for the industrial production of a wine. In addition, we demonstrated, at an industrial scale, the importance of non-Saccharomyces in the design of tailored starter cultures for typical wines. PMID:27242698

The Oenological Potential of Hanseniaspora uvarum in Simultaneous and Sequential Co-fermentation with Saccharomyces cerevisiae for Industrial Wine Production.

PubMed

Tristezza, Mariana; Tufariello, Maria; Capozzi, Vittorio; Spano, Giuseppe; Mita, Giovanni; Grieco, Francesco

2016-01-01

In oenology, the utilization of mixed starter cultures composed by Saccharomyces and non-Saccharomyces yeasts is an approach of growing importance for winemakers in order to enhance sensory quality and complexity of the final product without compromising the general quality and safety of the oenological products. In fact, several non-Saccharomyces yeasts are already commercialized as oenological starter cultures to be used in combination with Saccharomyces cerevisiae, while several others are the subject of various studies to evaluate their application. Our aim, in this study was to assess, for the first time, the oenological potential of H. uvarum in mixed cultures (co-inoculation) and sequential inoculation with S. cerevisiae for industrial wine production. Three previously characterized H. uvarum strains were separately used as multi-starter together with an autochthonous S. cerevisiae starter culture in lab-scale micro-vinification trials. On the basis of microbial development, fermentation kinetics and secondary compounds formation, the strain H. uvarum ITEM8795 was further selected and it was co- and sequentially inoculated, jointly with the S. cerevisiae starter, in a pilot scale wine production. The fermentation course and the quality of final product indicated that the co-inoculation was the better performing modality of inoculum. The above results were finally validated by performing an industrial scale vinification The mixed starter was able to successfully dominate the different stages of the fermentation process and the H. uvarum strain ITEM8795 contributed to increasing the wine organoleptic quality and to simultaneously reduce the volatile acidity. At the best of our knowledge, the present report is the first study regarding the utilization of a selected H. uvarum strain in multi-starter inoculation with S. cerevisiae for the industrial production of a wine. In addition, we demonstrated, at an industrial scale, the importance of non-Saccharomyces in the design of tailored starter cultures for typical wines.

Implementation of a 3D mixing layer code on parallel computers

NASA Technical Reports Server (NTRS)

Roe, K.; Thakur, R.; Dang, T.; Bogucz, E.

1995-01-01

This paper summarizes our progress and experience in the development of a Computational-Fluid-Dynamics code on parallel computers to simulate three-dimensional spatially-developing mixing layers. In this initial study, the three-dimensional time-dependent Euler equations are solved using a finite-volume explicit time-marching algorithm. The code was first programmed in Fortran 77 for sequential computers. The code was then converted for use on parallel computers using the conventional message-passing technique, while we have not been able to compile the code with the present version of HPF compilers.

Sequential bottom-up assembly of mechanically stabilized synthetic cells by microfluidics

NASA Astrophysics Data System (ADS)

Weiss, Marian; Frohnmayer, Johannes Patrick; Benk, Lucia Theresa; Haller, Barbara; Janiesch, Jan-Willi; Heitkamp, Thomas; Börsch, Michael; Lira, Rafael B.; Dimova, Rumiana; Lipowsky, Reinhard; Bodenschatz, Eberhard; Baret, Jean-Christophe; Vidakovic-Koch, Tanja; Sundmacher, Kai; Platzman, Ilia; Spatz, Joachim P.

2018-01-01

Compartments for the spatially and temporally controlled assembly of biological processes are essential towards cellular life. Synthetic mimics of cellular compartments based on lipid-based protocells lack the mechanical and chemical stability to allow their manipulation into a complex and fully functional synthetic cell. Here, we present a high-throughput microfluidic method to generate stable, defined sized liposomes termed `droplet-stabilized giant unilamellar vesicles (dsGUVs)’. The enhanced stability of dsGUVs enables the sequential loading of these compartments with biomolecules, namely purified transmembrane and cytoskeleton proteins by microfluidic pico-injection technology. This constitutes an experimental demonstration of a successful bottom-up assembly of a compartment with contents that would not self-assemble to full functionality when simply mixed together. Following assembly, the stabilizing oil phase and droplet shells are removed to release functional self-supporting protocells to an aqueous phase, enabling them to interact with physiologically relevant matrices.

Glycerol production by Oenococcus oeni during sequential and simultaneous cultures with wine yeast strains.

PubMed

Ale, Cesar E; Farías, Marta E; Strasser de Saad, Ana M; Pasteris, Sergio E

2014-07-01

Growth and fermentation patterns of Saccharomyces cerevisiae, Kloeckera apiculata, and Oenococcus oeni strains cultured in grape juice medium were studied. In pure, sequential and simultaneous cultures, the strains reached the stationary growth phase between 2 and 3 days. Pure and mixed K. apiculata and S. cerevisiae cultures used mainly glucose, producing ethanol, organic acids, and 4.0 and 0.1 mM glycerol, respectively. In sequential cultures, O. oeni achieved about 1 log unit at 3 days using mainly fructose and L-malic acid. Highest sugars consumption was detected in K. apiculata supernatants, lactic acid being the major end-product. 8.0 mM glycerol was found in 6-day culture supernatants. In simultaneous cultures, total sugars and L-malic acid were used at 3 days and 98% of ethanol and glycerol were detected. This study represents the first report of the population dynamics and metabolic behavior of yeasts and O. oeni in sequential and simultaneous cultures and contributes to the selection of indigenous strains to design starter cultures for winemaking, also considering the inclusion of K. apiculata. The sequential inoculation of yeasts and O. oeni would enhance glycerol production, which confers desirable organoleptic characteristics to wines, while organic acids levels would not affect their sensory profile. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Using case study within a sequential explanatory design to evaluate the impact of specialist and advanced practice roles on clinical outcomes: the SCAPE study.

PubMed

Lalor, Joan G; Casey, Dympna; Elliott, Naomi; Coyne, Imelda; Comiskey, Catherine; Higgins, Agnes; Murphy, Kathy; Devane, Declan; Begley, Cecily

2013-04-08

The role of the clinical nurse/midwife specialist and advanced nurse/midwife practitioner is complex not least because of the diversity in how the roles are operationalised across health settings and within multidisciplinary teams. This aim of this paper is to use The SCAPE Study: Specialist Clinical and Advanced Practitioner Evaluation in Ireland to illustrate how case study was used to strengthen a Sequential Explanatory Design. In Phase 1, clinicians identified indicators of specialist and advanced practice which were then used to guide the instrumental case study design which formed the second phase of the larger study. Phase 2 used matched case studies to evaluate the effectiveness of specialist and advanced practitioners on clinical outcomes for service users. Data were collected through observation, documentary analysis, and interviews. Observations were made of 23 Clinical Specialists or Advanced Practitioners, and 23 matched clinicians in similar matched non-postholding sites, while they delivered care. Forty-one service users, 41 clinicians, and 23 Directors of Nursing or Midwifery were interviewed, and 279 service users completed a survey based on the components of CS and AP practice identified in Phase 1. A coding framework, and the generation of cross tabulation matrices in NVivo, was used to make explicit how the outcome measures were confirmed and validated from multiple sources. This strengthened the potential to examine single cases that seemed 'different', and allowed for cases to be redefined. Phase 3 involved interviews with policy-makers to set the findings in context. Case study is a powerful research strategy to use within sequential explanatory mixed method designs, and adds completeness to the exploration of complex issues in clinical practice. The design is flexible, allowing the use of multiple data collection methods from both qualitative and quantitative paradigms. Multiple approaches to data collection are needed to evaluate the impact of complex roles and interventions in health care outcomes and service delivery. Case study design is an appropriate methodology to use when study outcomes relate to clinical practice.

Effect of chemical and physical heterogeneities on colloid-facilitated cesium transport

DOE PAGES

Rod, Kenton; Um, Wooyong; Chun, Jaehun; ...

2018-03-31

A set of column experiments was conducted to investigate the chemical and physical heterogeneity effect on colloid facilitated transport under slow pore velocity conditions. Pore velocities were kept below 100 cm d -1 for all experiments. Glass beads were packed into columns establishing four different conditions: 1) homogeneous, 2) mixed physical heterogeneity, 3) sequentially layered physical heterogeneity, and 4) chemical heterogeneity. The homogeneous column was packed with glass beads (diameter 500–600 μm), and physical heterogeneities were created by sequential layering or mixing two sizes of glass bead (500–600 μm and 300–400 μm). A chemical heterogeneity was created using 25% ofmore » the glass beads coated with hydrophobic molecules (1H-1H-2H-2H-perfluorooctyltrichlorosilane) mixed with 75% pristine glass beads (all 500–600 μm). Input solution with 0.5 mM CsI and 50 mg L -1 colloids (1-μm diameter SiO 2) was pulsed into columns under saturated conditions. The physical heterogeneity in the packed glass beads retarded the transport of colloids compared to homogeneous (R = 25.0), but showed only slight differences between sequentially layered (R = 60.7) and mixed heterogeneity(R = 62.4). The column with the chemical, hydrophobic/hydrophilic, heterogeneity removed most of the colloids from the input solution. All column conditions stripped Cs from colloids onto the column matrix of packed glass beads.« less

Effect of chemical and physical heterogeneities on colloid-facilitated cesium transport

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

Rod, Kenton; Um, Wooyong; Chun, Jaehun

A set of column experiments was conducted to investigate the chemical and physical heterogeneity effect on colloid facilitated transport under slow pore velocity conditions. Pore velocities were kept below 100 cm d -1 for all experiments. Glass beads were packed into columns establishing four different conditions: 1) homogeneous, 2) mixed physical heterogeneity, 3) sequentially layered physical heterogeneity, and 4) chemical heterogeneity. The homogeneous column was packed with glass beads (diameter 500–600 μm), and physical heterogeneities were created by sequential layering or mixing two sizes of glass bead (500–600 μm and 300–400 μm). A chemical heterogeneity was created using 25% ofmore » the glass beads coated with hydrophobic molecules (1H-1H-2H-2H-perfluorooctyltrichlorosilane) mixed with 75% pristine glass beads (all 500–600 μm). Input solution with 0.5 mM CsI and 50 mg L -1 colloids (1-μm diameter SiO 2) was pulsed into columns under saturated conditions. The physical heterogeneity in the packed glass beads retarded the transport of colloids compared to homogeneous (R = 25.0), but showed only slight differences between sequentially layered (R = 60.7) and mixed heterogeneity(R = 62.4). The column with the chemical, hydrophobic/hydrophilic, heterogeneity removed most of the colloids from the input solution. All column conditions stripped Cs from colloids onto the column matrix of packed glass beads.« less

Utilising a collective case study system theory mixed methods approach: a rural health example

PubMed Central

2014-01-01

Background Insight into local health service provision in rural communities is limited in the literature. The dominant workforce focus in the rural health literature, while revealing issues of shortage of maldistribution, does not describe service provision in rural towns. Similarly aggregation of data tends to render local health service provision virtually invisible. This paper describes a methodology to explore specific aspects of rural health service provision with an initial focus on understanding rurality as it pertains to rural physiotherapy service provision. Method A system theory-case study heuristic combined with a sequential mixed methods approach to provide a framework for both quantitative and qualitative exploration across sites. Stakeholder perspectives were obtained through surveys and in depth interviews. The investigation site was a large area of one Australian state with a mix of rural, regional and remote communities. Results 39 surveys were received from 11 locations within the investigation site and 19 in depth interviews were conducted. Stakeholder perspectives of rurality and workforce numbers informed the development of six case types relevant to the exploration of rural physiotherapy service provision. Participant perspective of rurality often differed with the geographical classification of their location. The numbers of onsite colleagues and local access to health services contributed to participant perceptions of rurality. Conclusions The complexity of understanding the concept of rurality was revealed by interview participants when providing their perspectives about rural physiotherapy service provision. Dual measures, such as rurality and workforce numbers, provide more relevant differentiation of sites to explore specific services, such rural physiotherapy service provision, than single measure of rurality as defined by geographic classification. The system theory-case study heuristic supports both qualitative and quantitative exploration in rural health services research. PMID:25066241

A mixed study systematic review of social media in nursing and midwifery education: Protocol.

PubMed

O'Connor, Siobhan; Jolliffe, Sarah; Stanmore, Emma; Renwick, Laoise; Schmitt, Terri; Booth, Richard

2017-08-01

To synthesize evidence on the use of social media in nursing and midwifery education. Social media is one type of online platform that is being explored to determine if there is value in using interactive, digital communication tools to support how nurses and midwives learn in a variety of settings. A sequential explanatory synthesis approach will be used for this mixed study review. Five bibliographic databases; PubMed, MEDLINE, CINAHL, Scopus, and ERIC will be searched using a combination of keywords relevant to social networking and social media, nursing and midwifery, and education. The search will not be limited by year of publication. Titles, abstracts, and full papers will be screened by two independent reviewers against inclusion and exclusion criteria, with any disagreements resolved via a third reviewer. Selected studies will undergo quality assessment and data extraction. Data synthesis will occur in three sequential phases, with quantitative and qualitative data analysed separately and then integrated where possible to provide a conceptual framework illustrating learning via social media. Funding for this review was confirmed in May 2016 by Sigma Theta Tau International and the National League for Nursing. The mixed study systematic review will produce the first rigorous synthesis on the use of social media in nursing and midwifery education and will have important implications for educators as well as students. It will also highlight knowledge gaps and make recommendations on the use of this novel technology in higher and continuing education. © 2017 John Wiley & Sons Ltd.

An Overview of Markov Chain Methods for the Study of Stage-Sequential Developmental Processes

ERIC Educational Resources Information Center

Kapland, David

2008-01-01

This article presents an overview of quantitative methodologies for the study of stage-sequential development based on extensions of Markov chain modeling. Four methods are presented that exemplify the flexibility of this approach: the manifest Markov model, the latent Markov model, latent transition analysis, and the mixture latent Markov model.…

Organizational supports used by private child and family serving agencies to facilitate evidence use: a mixed methods study protocol.

PubMed

Chuang, Emmeline; Collins-Camargo, Crystal; McBeath, Bowen

2017-04-08

Challenges to evidence use are well documented. Less well understood are the formal supports-e.g., technical infrastructure, inter-organizational relationships-organizations may put in place to help overcome these challenges. This study will identify supports for evidence use currently used by private child and family serving agencies delivering publicly funded behavioral health and/or human services; examine contextual, organizational, and managerial factors associated with use of such supports; and determine how identified supports affect evidence use by staff at multiple levels of the organization. We will use a sequential explanatory mixed methods design, with study activities occurring in two sequential phases: In phase 1, quantitative survey data collected from managers of private child and family serving agencies in six states (CA, IN, KY, MO, PA, and WI) and analyzed using both regression and qualitative comparative analysis (QCA) will identify organizational supports currently being used to facilitate evidence use and examine the contextual, organizational, and managerial factors associated with the use of such supports. In phase 2, data from phase 1 will be used to select a purposive sample of 12 agencies for in-depth case studies. In those 12 agencies, semi-structured interviews with key informants and managers, focus groups with frontline staff, and document analysis will provide further insight into agencies' motivation for investing in organizational supports for evidence use and the facilitators and barriers encountered in doing so. Semi-structured interviews with managers and focus groups with frontline staff will also assess whether and how identified supports affect evidence use at different levels of the organization (senior executives, middle managers, frontline supervisors, and frontline staff). Within- and between-case analyses supplemented by QCA will identify combinations of factors associated with the highest and lowest levels of staff evidence use. This study will inform efforts to improve sustainment, scale-up, and spread of evidence by providing insight into organizational and managerial strategies that facilitate evidence use, the contexts in which these strategies are most effective, and their effect on evidence use by staff at different levels of the organization.

Using Student-Teachers' Reports of Self-Efficacy to Evaluate an Early Childhood Science Course

ERIC Educational Resources Information Center

Giallousi, Maria; Tselfes, Vasilis; Gialamas, Vasilis

2014-01-01

The purpose of this study was to evaluate teaching effectiveness in an elective science course, in the Early Childhood Education Department of Athens University in Greece. For this, a sequential mixed research design was applied to investigate freshmen beliefs about the effectiveness of their future teaching in kindergarten. An enhancement and a…

Pre-Service Secondary Mathematics Teachers' Metacognitive Awareness and Metacognitive Behaviours in Problem Solving Processes

ERIC Educational Resources Information Center

Bas, Fatih

2016-01-01

This study aims to observe the pre-service secondary mathematics teachers' metacognitive awareness in terms of the variables gender and class level and determine their metacognitive behaviours which showed in the non-routine problems. A partially mixed sequential dominant status design was carried out with a total of 287 participants. The data of…

Developmental plasticity in Tenebrio molitor (Coleoptera: Tenebrionidae): Analysis of Instar Variation in Number and Development Time under Different Diets

USDA-ARS?s Scientific Manuscript database

The variation in instar number and the pattern of sequential instar development time of Tenebrio molitor L. (Coleoptera: Tenebrionidae) was studied under 4 different diet regimes. Addition of dietary supplements consisting of dry potato or a mix of dry potato and dry egg whites significantly reduced...

Candida zemplinina can reduce acetic acid produced by Saccharomyces cerevisiae in sweet wine fermentations.

PubMed

Rantsiou, Kalliopi; Dolci, Paola; Giacosa, Simone; Torchio, Fabrizio; Tofalo, Rosanna; Torriani, Sandra; Suzzi, Giovanna; Rolle, Luca; Cocolin, Luca

2012-03-01

In this study we investigated the possibility of using Candida zemplinina, as a partner of Saccharomyces cerevisiae, in mixed fermentations of must with a high sugar content, in order to reduce its acetic acid production. Thirty-five C. zemplinina strains, which were isolated from different geographic regions, were molecularly characterized, and their fermentation performances were determined. Five genetically different strains were selected for mixed fermentations with S. cerevisiae. Two types of inoculation were carried out: coinoculation and sequential inoculation. A balance between the two species was generally observed for the first 6 days, after which the levels of C. zemplinina started to decrease. Relevant differences were observed concerning the consumption of sugars, the ethanol and glycerol content, and acetic acid production, depending on which strain was used and which type of inoculation was performed. Sequential inoculation led to the reduction of about half of the acetic acid content compared to the pure S. cerevisiae fermentation, but the ethanol and glycerol amounts were also low. A coinoculation with selected combinations of S. cerevisiae and C. zemplinina resulted in a decrease of ~0.3 g of acetic acid/liter, while maintaining high ethanol and glycerol levels. This study demonstrates that mixed S. cerevisiae and C. zemplinina fermentation could be applied in sweet wine fermentation to reduce the production of acetic acid, connected to the S. cerevisiae osmotic stress response.

Mixed Methods in Prostate Cancer Prevention and Service Utilization Planning: Combining Focus Groups, Survey Research, and Community Engagement.

PubMed

Tataw, David Besong; Ekúndayò, Olúgbémiga T

2017-01-01

This article reports on the use of sequential and integrated mixed-methods approach in a focused population and small-area analysis. The study framework integrates focus groups, survey research, and community engagement strategies in a search for evidence related to prostate cancer screening services utilization as a component of cancer prevention planning in a marginalized African American community in the United States. Research and data analysis methods are synthesized by aggregation, configuration, and interpretive analysis. The results of synthesis show that qualitative and quantitative data validate and complement each other in advancing our knowledge of population characteristics, variable associations, the complex context in which variables exist, and the best options for prevention and service planning. Synthesis of findings and interpretive analysis provided two important explanations which seemed inexplicable in regression outputs: (a) Focus group data on the limitations of the church as an educational source explain the negative association between preferred educational channels and screening behavior found in quantitative analysis. (b) Focus group data on unwelcoming provider environments explain the inconsistent relationship between knowledge of local sites and screening services utilization found in quantitative analysis. The findings suggest that planners, evaluators, and scientists should grow their planning and evaluation evidence from the community they serve.

Using theatre to address mental illness stigma: a knowledge translation study in bipolar disorder.

PubMed

Michalak, Erin E; Livingston, James D; Maxwell, Victoria; Hole, Rachelle; Hawke, Lisa D; Parikh, Sagar V

2014-01-01

Reduction of the stigma of mental illness is an international priority; arts- and contact-based approaches represent a promising mode of intervention. This project was designed to explore the impact of a one-woman theatrical performance on attitudes towards bipolar disorder (BD) on people with BD and healthcare providers. A playwright and actress who lives with BD developed a stage performance - 'That's Just Crazy Talk' - targeting stigmatizing attitudes towards BD. Prospective, longitudinal and sequential mixed methods were used to assess the impact of the performance on people with BD (n = 80) and healthcare providers (n = 84). Qualitative interviews were conducted with 33 participants (14 people with BD and 19 healthcare providers). Quantitatively, healthcare providers showed significantly improved attitudes immediately post-performance, but this change was not maintained over time; people with BD showed little quantitative change. Qualitatively, both people with BD and BD healthcare providers showed enduring and broadly positive changes. A theatrical presentation designed to reduce stigma produced immediate impact on healthcare providers quantitatively and significant qualitative impact on people with BD and healthcare providers. Additionally, the utility of using mixed-method approaches in mental health research was demonstrated.

An Emic, Mixed Methods Approach to Defining and Measuring Positive Parenting Among Low-Income, Black Families

PubMed Central

McWayne, Christine; Mattis, Jacqueline S.; Wright, Linnie E. Green; Limlingan, Maria Cristina; Harris, Elise

2017-01-01

Research Findings This within-group exploratory sequential mixed methods investigation sought to identify how ethnically diverse, urban-residing, low-income Black families conceptualize positive parenting. During the item development phase 119 primary caregivers from Head Start programs participated in focus groups and interviews. These qualitative data were content analyzed using a three-stage iterative process that resulted in the development of a final set of 72 items for a paper-and-pencil measure. In the measure validation phase of the study initial construct validity of the 72-item measure was assessed with an independent sample of 665 respondents. Common factor analyses revealed five dimensions of positive parenting on the Black Parenting Strengths in Context (BPSC) scale that related in expected ways with other parent self-report measures. Practice and Policy BPSC dimensions provide initial support for a more nuanced operationalization of positive parenting than currently exists in any single scale for use with this group, and hold promise for better honoring the culture- and context-specific parenting goals and practices that low-income, Black parents subjectively view as important for producing healthy developmental outcomes for their children. PMID:29333053

Insights on leadership from early career nurse academics: findings from a mixed methods study.

PubMed

Halcomb, Elizabeth; Jackson, Debra; Daly, John; Gray, Joanne; Salamonson, Yenna; Andrew, Sharon; Peters, Kath

2016-03-01

To explore the perceptions of early career nursing academics on leadership in academia. There is growing emphasis on leadership capacity building across all domains of nursing. However, there is limited evidence on leadership capacity in early career academics. This study tested an intervention to develop leadership capacity amongst early career nursing academics in two Australian universities. A sequential mixed methods design, using online surveys and semi-structured interviews, was used to collect data. Twenty-three early career nursing academics participated. Most had experience of formal leadership roles and were aware of its importance to them as they developed their academic careers. Participants were able to discuss their own views of themselves as leaders; their perceptions of their own needs for leadership development, and ways in which they could seek to develop further as leaders. There is a need to provide initial and ongoing opportunities for leadership development amongst nurse academics. These opportunities should be contextualised and recognise factors such as gender, and the effects of structural oppression. Nurse academics are involved in the preparation of the next generation of clinical leaders and it is imperative that they are able to articulate a clear view of leadership. © 2015 John Wiley & Sons Ltd.

Are mHealth Interventions to Improve Child Restraint System Installation of Value? A Mixed Methods Study of Parents

PubMed Central

Fleisher, Linda; Erkoboni, Danielle; Halkyard, Katherine; Sykes, Emily; Norris, Marisol S.; Walker, Lorrie; Winston, Flaura

2017-01-01

Childhood death from vehicle crashes and the delivery of information about proper child restraint systems (CRS) use continues to be a critical public health issue. Safe Seat, a sequential, mixed-methods study identified gaps in parental knowledge about and perceived challenges in the use of appropriate CRS and insights into the preferences of various technological approaches to deliver CRS education. Focus groups (eight groups with 21 participants) and a quantitative national survey (N = 1251) using MTurk were conducted. Although there were differences in the age, racial/ethnic background, and educational level between the focus group participants and the national sample, there was a great deal of consistency in the need for more timely and personalized information about CRS. The majority of parents did not utilize car seat check professionals although they expressed interest in and lack of knowledge about how to access these resources. Although there was some interest in an app that would be personalized and able to push just-in-time content (e.g., new guidelines, location and times of car seat checks), content that has sporadic relevance (e.g., initial installation) seemed more appropriate for a website. Stakeholder input is critical to guide the development and delivery of acceptable and useful child safety education. PMID:28954429

Are mHealth Interventions to Improve Child Restraint System Installation of Value? A Mixed Methods Study of Parents.

PubMed

Fleisher, Linda; Erkoboni, Danielle; Halkyard, Katherine; Sykes, Emily; Norris, Marisol S; Walker, Lorrie; Winston, Flaura

2017-09-26

Childhood death from vehicle crashes and the delivery of information about proper child restraint systems (CRS) use continues to be a critical public health issue. Safe Seat, a sequential, mixed-methods study identified gaps in parental knowledge about and perceived challenges in the use of appropriate CRS and insights into the preferences of various technological approaches to deliver CRS education. Focus groups (eight groups with 21 participants) and a quantitative national survey (N = 1251) using MTurk were conducted. Although there were differences in the age, racial/ethnic background, and educational level between the focus group participants and the national sample, there was a great deal of consistency in the need for more timely and personalized information about CRS. The majority of parents did not utilize car seat check professionals although they expressed interest in and lack of knowledge about how to access these resources. Although there was some interest in an app that would be personalized and able to push just-in-time content (e.g., new guidelines, location and times of car seat checks), content that has sporadic relevance (e.g., initial installation) seemed more appropriate for a website. Stakeholder input is critical to guide the development and delivery of acceptable and useful child safety education.

The Role of Managers in Employee Wellness Programs: A Mixed-Methods Study.

PubMed

Passey, Deborah G; Hammerback, Kristen; Huff, Aaron; Harris, Jeffrey R; Hannon, Peggy A

2018-01-01

The purpose of this study is to evaluate managers' barriers and facilitators to supporting employee participation in the Washington State Wellness program. Exploratory sequential mixed methods. Four Washington State agencies located in Olympia and Tumwater, Washington. State employees in management positions (executive, middle, and line), whose job includes supervision of subordinates and responsibility for the performance and conduct of a subunit or group. We interviewed 23 managers and then used the results to create a survey that was fielded to all managers at the 4 agencies. The survey response rate was 65% (n = 607/935). We used qualitative coding techniques to analyze interview transcripts and descriptive statistics to summarize survey data. We used the Total Worker Health framework to organize our findings and conclusions. Managers support the wellness program, but they also face challenges with accommodating employees' participation due to workload, scheduling inflexibility, and self-efficacy to discuss wellness with direct reports. About half the managers receive support from the manager above them, and most have not received training on the wellness program. Our findings point to several strategies that can strengthen managers' role in supporting the wellness program: the provision of training, targeted messages, formal expectations, and encouragement (from the manager above) to support employees' participation.

Comparing multiple imputation methods for systematically missing subject-level data.

PubMed

Kline, David; Andridge, Rebecca; Kaizar, Eloise

2017-06-01

When conducting research synthesis, the collection of studies that will be combined often do not measure the same set of variables, which creates missing data. When the studies to combine are longitudinal, missing data can occur on the observation-level (time-varying) or the subject-level (non-time-varying). Traditionally, the focus of missing data methods for longitudinal data has been on missing observation-level variables. In this paper, we focus on missing subject-level variables and compare two multiple imputation approaches: a joint modeling approach and a sequential conditional modeling approach. We find the joint modeling approach to be preferable to the sequential conditional approach, except when the covariance structure of the repeated outcome for each individual has homogenous variance and exchangeable correlation. Specifically, the regression coefficient estimates from an analysis incorporating imputed values based on the sequential conditional method are attenuated and less efficient than those from the joint method. Remarkably, the estimates from the sequential conditional method are often less efficient than a complete case analysis, which, in the context of research synthesis, implies that we lose efficiency by combining studies. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

CFD simulation of hemodynamics in sequential and individual coronary bypass grafts based on multislice CT scan datasets.

PubMed

Hajati, Omid; Zarrabi, Khalil; Karimi, Reza; Hajati, Azadeh

2012-01-01

There is still controversy over the differences in the patency rates of the sequential and individual coronary artery bypass grafting (CABG) techniques. The purpose of this paper was to non-invasively evaluate hemodynamic parameters using complete 3D computational fluid dynamics (CFD) simulations of the sequential and the individual methods based on the patient-specific data extracted from computed tomography (CT) angiography. For CFD analysis, the geometric model of coronary arteries was reconstructed using an ECG-gated 64-detector row CT. Modeling the sequential and individual bypass grafting, this study simulates the flow from the aorta to the occluded posterior descending artery (PDA) and the posterior left ventricle (PLV) vessel with six coronary branches based on the physiologically measured inlet flow as the boundary condition. The maximum calculated wall shear stress (WSS) in the sequential and the individual models were estimated to be 35.1 N/m(2) and 36.5 N/m(2), respectively. Compared to the individual bypass method, the sequential graft has shown a higher velocity at the proximal segment and lower spatial wall shear stress gradient (SWSSG) due to the flow splitting caused by the side-to-side anastomosis. Simulated results combined with its surgical benefits including the requirement of shorter vein length and fewer anastomoses advocate the sequential method as a more favorable CABG method.

Reducing the blame culture through clinical audit in nuclear medicine: a mixed methods study.

PubMed

Ross, P; Hubert, J; Wong, W L

2017-02-01

To identify the barriers and facilitators of doctors' engagement with clinical audit and to explore how and why these factors influenced doctors' decisions to engage with the NHS National Clinical Audit Programme. A single-embedded case study. Mixed methods sequential approach with explorative pilot study and follow-up survey. Pilot study comprised 13 semi-structured interviews with purposefully selected consultant doctors over a six-month period. Interview data coded and analysed using directed thematic content analysis with themes compared against the study's propositions. Themes derived from the pilot study informed the online survey question items. Exploratory factor analysis using STATA and descriptive statistical methods applied to summarise findings. Data triangulation techniques used to corroborate and validate findings across the different methodological techniques. NHS National PET-CT Clinical Audit Programme. Doctors reporting on the Audit Programme. Extent of engagement with clinical audit, factors that influence engagement with clinical audit. Online survey: 58/59 doctors responded (98.3%). Audit was found to be initially threatening (79%); audit was reassuring (85%); audit helped validate professional competence (93%); participation in audit improved reporting skills (76%). Three key factors accounted for 97.6% of the variance in survey responses: (1) perception of audit's usefulness, (2) a common purpose, (3) a supportive blame free culture of trust. Factor 1 influenced medical engagement most. The study documents performance feedback as a key facilitator of medical engagement with clinical audit. It found that medical engagement with clinical audit was associated with reduced levels of professional anxiety and higher levels of perceived self-efficacy.

Asymptotic Properties of the Sequential Empirical ROC, PPV and NPV Curves Under Case-Control Sampling.

PubMed

Koopmeiners, Joseph S; Feng, Ziding

2011-01-01

The receiver operating characteristic (ROC) curve, the positive predictive value (PPV) curve and the negative predictive value (NPV) curve are three measures of performance for a continuous diagnostic biomarker. The ROC, PPV and NPV curves are often estimated empirically to avoid assumptions about the distributional form of the biomarkers. Recently, there has been a push to incorporate group sequential methods into the design of diagnostic biomarker studies. A thorough understanding of the asymptotic properties of the sequential empirical ROC, PPV and NPV curves will provide more flexibility when designing group sequential diagnostic biomarker studies. In this paper we derive asymptotic theory for the sequential empirical ROC, PPV and NPV curves under case-control sampling using sequential empirical process theory. We show that the sequential empirical ROC, PPV and NPV curves converge to the sum of independent Kiefer processes and show how these results can be used to derive asymptotic results for summaries of the sequential empirical ROC, PPV and NPV curves.

Asymptotic Properties of the Sequential Empirical ROC, PPV and NPV Curves Under Case-Control Sampling

PubMed Central

Koopmeiners, Joseph S.; Feng, Ziding

2013-01-01

The receiver operating characteristic (ROC) curve, the positive predictive value (PPV) curve and the negative predictive value (NPV) curve are three measures of performance for a continuous diagnostic biomarker. The ROC, PPV and NPV curves are often estimated empirically to avoid assumptions about the distributional form of the biomarkers. Recently, there has been a push to incorporate group sequential methods into the design of diagnostic biomarker studies. A thorough understanding of the asymptotic properties of the sequential empirical ROC, PPV and NPV curves will provide more flexibility when designing group sequential diagnostic biomarker studies. In this paper we derive asymptotic theory for the sequential empirical ROC, PPV and NPV curves under case-control sampling using sequential empirical process theory. We show that the sequential empirical ROC, PPV and NPV curves converge to the sum of independent Kiefer processes and show how these results can be used to derive asymptotic results for summaries of the sequential empirical ROC, PPV and NPV curves. PMID:24039313

Trend analysis of Trichinella in a red fox population from a low endemic area using a validated artificial digestion and sequential sieving technique.

PubMed

Franssen, Frits; Deksne, Gunita; Esíte, Zanda; Havelaar, Arie; Swart, Arno; van der Giessen, Joke

2014-11-28

Freezing of fox carcasses to minimize professional hazard of infection with Echinococcus multilocularis is recommended in endemic areas, but this could influence the detection of Trichinella larvae in the same host species. A method based on artificial digestion of frozen fox muscle, combined with larva isolation by a sequential sieving method (SSM), was validated using naturally infected foxes from Latvia. The validated SSM was used to detect dead Trichinella muscle larvae (ML) in frozen muscle samples of 369 red foxes from the Netherlands, of which one fox was positive (0.067 larvae per gram). This result was compared with historical Trichinella findings in Dutch red foxes. Molecular analysis using 5S PCR showed that both T. britovi and T. nativa were present in the Latvian foxes, without mixed infections. Of 96 non-frozen T. britovi ML, 94% was successfully sequenced, whereas this was the case for only 8.3% of 72 frozen T. britovi ML. The single Trichinella sp. larva that was recovered from the positive Dutch fox did not yield PCR product, probably due to severe freeze-damage. In conclusion, the SSM presented in this study is a fast and effective method to detect dead Trichinella larvae in frozen meat. We showed that the Trichinella prevalence in Dutch red fox was 0.27% (95% CI 0.065-1.5%), in contrast to 3.9% in the same study area fifteen years ago. Moreover, this study demonstrated that the efficacy of 5S PCR for identification of Trichinella britovi single larvae from frozen meat is not more than 8.3%.

Why do women pay more than they should? A mixed methods study of the implementation gap in a policy to subsidize the costs of deliveries in Burkina Faso.

PubMed

Ridde, Valéry; Kouanda, Seni; Yameogo, Maurice; Kadio, Kadidiatou; Bado, Aristide

2013-02-01

In 2007, Burkina Faso launched a public policy to subsidize 80% of the cost of normal deliveries. Although women are required to pay only the remaining 20%, i.e., 900F CFA (1.4 Euros), some qualitative evidence suggests they actually pay more. The aim of this study is to test and then (if confirmed) to understand the hypothesis that the amounts paid by women are more than the official fee, i.e., their 20% portion. A mixed method sequential explanatory design giving equal priority to both quantitative (n=883) and qualitative (n=50) methods was used in a rural health district of Ouargaye. Half (50%, median) of the women reported paying more than the official fee for a delivery. Health workers questioned the methodology of the study and the veracity of the women's reports. The three most plausible explanations for this payment disparity are: (i) the payments were for products used that were not part of the delivery kit covered by the official fee; (ii) the implementers had difficulty in understanding the policy; and (iii) there was improper conduct on the part of some health workers. Institutional design and organizational practices, as well as weak rule enforcement and organizational capacity, need to be considered more carefully to avoid an implementation gap in this public policy. Copyright © 2012 Elsevier Ltd. All rights reserved.

Aggression on haemodialysis units: a mixed method study.

PubMed

Jones, Julia; Nijman, Henk; Ross, Jamie; Ashman, Neil; Callaghan, Patrick

2014-09-01

Aggression on haemodialysis units is a growing problem internationally that has received little research attention to date. Aggressive behaviour by patients or their relatives can compromise the safety and well-being of staff and other patients sharing a haemodialysis session. The objectives of the study were twofold: First, to identify the prevalance and nature of aggression on haemodialysis units; and second, to investigate factors that contribute to aggressive behaviour on haemodialysis units. A cross-sectional, sequential mixed method research design was adopted, with two research methods utilised. Incidents of aggressive behaviour were recorded over a 12-month period, using a renal version of the Staff Observation Aggression Scale. Six months after the incident data collection had commenced, semi-structured qualitative interviews were conducted with 29 multidisciplinary members of staff. Over 12 months, 74 aggressive incidents were recorded. The majority of incidents involved verbal aggression, and the perpetrators were a minority of patients, relatives and staff. Two patients were responsible for 38% of all incidents; both patients had mental health problems. Distinct temporal patterns to the aggressive behaviour were observed according to the day of the week and time of day. This study demonstrates that aggression is a significant problem on haemodialysis units, with verbal aggression most prevalent. The temporal patterns to aggression observed are related to the uniqueness of the haemodialysis setting, with a distinctly different treatment environment compared with other healthcare settings. © 2014 European Dialysis and Transplant Nurses Association/European Renal Care Association.

A Novel Method for Discovering Fuzzy Sequential Patterns Using the Simple Fuzzy Partition Method.

ERIC Educational Resources Information Center

Chen, Ruey-Shun; Hu, Yi-Chung

2003-01-01

Discusses sequential patterns, data mining, knowledge acquisition, and fuzzy sequential patterns described by natural language. Proposes a fuzzy data mining technique to discover fuzzy sequential patterns by using the simple partition method which allows the linguistic interpretation of each fuzzy set to be easily obtained. (Author/LRW)

Miniaturizing and automation of free acidity measurements for uranium (VI)-HNO3 solutions: Development of a new sequential injection analysis for a sustainable radio-analytical chemistry.

PubMed

Néri-Quiroz, José; Canto, Fabrice; Guillerme, Laurent; Couston, Laurent; Magnaldo, Alastair; Dugas, Vincent

2016-10-01

A miniaturized and automated approach for the determination of free acidity in solutions containing uranium (VI) is presented. The measurement technique is based on the concept of sequential injection analysis with on-line spectroscopic detection. The proposed methodology relies on the complexation and alkalimetric titration of nitric acid using a pH 5.6 sodium oxalate solution. The titration process is followed by UV/VIS detection at 650nm thanks to addition of Congo red as universal pH indicator. Mixing sequence as well as method validity was investigated by numerical simulation. This new analytical design allows fast (2.3min), reliable and accurate free acidity determination of low volume samples (10µL) containing uranium/[H(+)] moles ratio of 1:3 with relative standard deviation of <7.0% (n=11). The linearity range of the free nitric acid measurement is excellent up to 2.77molL(-1) with a correlation coefficient (R(2)) of 0.995. The method is specific, presence of actinide ions up to 0.54molL(-1) does not interfere on the determination of free nitric acid. In addition to automation, the developed sequential injection analysis method greatly improves the standard off-line oxalate complexation and alkalimetric titration method by reducing thousand fold the required sample volume, forty times the nuclear waste per analysis as well as the analysis time by eight fold. These analytical parameters are important especially in nuclear-related applications to improve laboratory safety, personnel exposure to radioactive samples and to drastically reduce environmental impacts or analytical radioactive waste. Copyright © 2016 Elsevier B.V. All rights reserved.

Sequential nutrient uptake as a potential mechanism for phytoplankton to maintain high primary productivity and balanced nutrient stoichiometry

NASA Astrophysics Data System (ADS)

Yin, Kedong; Liu, Hao; Harrison, Paul J.

2017-05-01

We hypothesize that phytoplankton have the sequential nutrient uptake strategy to maintain nutrient stoichiometry and high primary productivity in the water column. According to this hypothesis, phytoplankton take up the most limiting nutrient first until depletion, continue to draw down non-limiting nutrients and then take up the most limiting nutrient rapidly when it is available. These processes would result in the variation of ambient nutrient ratios in the water column around the Redfield ratio. We used high-resolution continuous vertical profiles of nutrients, nutrient ratios and on-board ship incubation experiments to test this hypothesis in the Strait of Georgia. At the surface in summer, ambient NO3- was depleted with excess PO43- and SiO4- remaining, and as a result, both N : P and N : Si ratios were low. The two ratios increased to about 10 : 1 and 0. 45 : 1, respectively, at 20 m. Time series of vertical profiles showed that the leftover PO43- continued to be removed, resulting in additional phosphorus storage by phytoplankton. The N : P ratios at the nutricline in vertical profiles responded differently to mixing events. Field incubation of seawater samples also demonstrated the sequential uptake of NO3- (the most limiting nutrient) and then PO43- and SiO4- (the non-limiting nutrients). This sequential uptake strategy allows phytoplankton to acquire additional cellular phosphorus and silicon when they are available and wait for nitrogen to become available through frequent mixing of NO3- (or pulsed regenerated NH4). Thus, phytoplankton are able to maintain high productivity and balance nutrient stoichiometry by taking advantage of vigorous mixing regimes with the capacity of the stoichiometric plasticity. To our knowledge, this is the first study to show the in situ dynamics of continuous vertical profiles of N : P and N : Si ratios, which can provide insight into the in situ dynamics of nutrient stoichiometry in the water column and the inference of the transient status of phytoplankton nutrient stoichiometry in the coastal ocean.

Step-by-step guideline for disease-specific costing studies in low- and middle-income countries: a mixed methodology

PubMed Central

Hendriks, Marleen E.; Kundu, Piyali; Boers, Alexander C.; Bolarinwa, Oladimeji A.; te Pas, Mark J.; Akande, Tanimola M.; Agbede, Kayode; Gomez, Gabriella B.; Redekop, William K.; Schultsz, Constance; Tan, Siok Swan

2014-01-01

Background Disease-specific costing studies can be used as input into cost-effectiveness analyses and provide important information for efficient resource allocation. However, limited data availability and limited expertise constrain such studies in low- and middle-income countries (LMICs). Objective To describe a step-by-step guideline for conducting disease-specific costing studies in LMICs where data availability is limited and to illustrate how the guideline was applied in a costing study of cardiovascular disease prevention care in rural Nigeria. Design The step-by-step guideline provides practical recommendations on methods and data requirements for six sequential steps: 1) definition of the study perspective, 2) characterization of the unit of analysis, 3) identification of cost items, 4) measurement of cost items, 5) valuation of cost items, and 6) uncertainty analyses. Results We discuss the necessary tradeoffs between the accuracy of estimates and data availability constraints at each step and illustrate how a mixed methodology of accurate bottom-up micro-costing and more feasible approaches can be used to make optimal use of all available data. An illustrative example from Nigeria is provided. Conclusions An innovative, user-friendly guideline for disease-specific costing in LMICs is presented, using a mixed methodology to account for limited data availability. The illustrative example showed that the step-by-step guideline can be used by healthcare professionals in LMICs to conduct feasible and accurate disease-specific cost analyses. PMID:24685170

A weight modification sequential method for VSC-MTDC power system state estimation

NASA Astrophysics Data System (ADS)

Yang, Xiaonan; Zhang, Hao; Li, Qiang; Guo, Ziming; Zhao, Kun; Li, Xinpeng; Han, Feng

2017-06-01

This paper presents an effective sequential approach based on weight modification for VSC-MTDC power system state estimation, called weight modification sequential method. The proposed approach simplifies the AC/DC system state estimation algorithm through modifying the weight of state quantity to keep the matrix dimension constant. The weight modification sequential method can also make the VSC-MTDC system state estimation calculation results more ccurate and increase the speed of calculation. The effectiveness of the proposed weight modification sequential method is demonstrated and validated in modified IEEE 14 bus system.

Use of Torulaspora delbrueckii Co-fermentation With Two Saccharomyces cerevisiae Strains With Different Aromatic Characteristic to Improve the Diversity of Red Wine Aroma Profile

PubMed Central

Zhang, Bo-Qin; Luan, Yu; Duan, Chang-Qing; Yan, Guo-Liang

2018-01-01

The use of selected Saccharomyces and non-Saccharomyces strains as mixed starters has advantages over pure fermentation due to achieving wine products with distinctive and diversified aroma expected by consumers. To obtain a way to improve the aroma diversity and increase the differentiation of wine product, in this study, the aromatic effect of multi-culture of indigenous Torulaspora delbrueckii (TD12), simultaneous and sequential inoculation with two Saccharomyces strains (indigenous icewine yeast SC45 and commercial yeast BDX) with different enological characteristics were investigated in laboratory-scale 20 L fermenter, respectively. The results showed that T. delbrueckii co-fermented with different S. cerevisiae strain could generate diversified physicochemical and aromatic quality of wine as evidenced by PCA. Mixed fermentation of SC45/TD12 produced higher contents of higher alcohol (3-methyl-1-pentanol and phenylethyl alcohol), ethyl esters (ethyl decanoate and ethyl butanoate), terpenes and phenylacetaldehyde with less fatty acids (hexanoic acid, octanoic acid) and acetic acid, while BDX/TD12 generated more C6 alcohol (1-hexanol) and acetate esters (ethyl acetate and isoamyl acetate). Compared to simultaneous inoculation, sequential inoculation could achieve higher aroma diversity, and generate higher intensity of fruity, flowery and sweet attributes of wine as assessed by calculating the odor activity values. The different S. cerevisiae strain and inoculation method in alcoholic fermentation could further influence the formations of aromatic compounds in malolactic fermentation. Our results highlighted the importance of S. cerevisiae strain in shaping the aromatic quality of wine in mixed fermentation, and also suggested that using different S. cerevisiae strains with distinct aromatic characteristics co-fermentation with specific non-Saccharomyces strain is a potential way to increase the aromatic diversity and quality of wine product, which could provide an alternative way to meet the requirement of wine consumers for diversified aromatic quality. PMID:29674999

Group Sequential Testing of the Predictive Accuracy of a Continuous Biomarker with Unknown Prevalence

PubMed Central

Koopmeiners, Joseph S.; Feng, Ziding

2015-01-01

Group sequential testing procedures have been proposed as an approach to conserving resources in biomarker validation studies. Previously, Koopmeiners and Feng (2011) derived the asymptotic properties of the sequential empirical positive predictive value (PPV) and negative predictive value curves, which summarize the predictive accuracy of a continuous marker, under case-control sampling. A limitation of their approach is that the prevalence can not be estimated from a case-control study and must be assumed known. In this manuscript, we consider group sequential testing of the predictive accuracy of a continuous biomarker with unknown prevalence. First, we develop asymptotic theory for the sequential empirical PPV and NPV curves when the prevalence must be estimated, rather than assumed known in a case-control study. We then discuss how our results can be combined with standard group sequential methods to develop group sequential testing procedures and bias-adjusted estimators for the PPV and NPV curve. The small sample properties of the proposed group sequential testing procedures and estimators are evaluated by simulation and we illustrate our approach in the context of a study to validate a novel biomarker for prostate cancer. PMID:26537180

Tensiometry and dilational rheology of mixed β-lactoglobulin/ionic surfactant adsorption layers at water/air and water/hexane interfaces.

PubMed

Dan, Abhijit; Gochev, Georgi; Miller, Reinhard

2015-07-01

Oscillating drop tensiometry was applied to study adsorbed interfacial layers at water/air and water/hexane interfaces formed from mixed solutions of β-lactoglobulin (BLG, 1 μM in 10 mM buffer, pH 7 - negative net charge) and the anionic surfactant SDS or the cationic DoTAB. The interfacial pressure Π and the dilational viscoelasticity modulus |E| of the mixed layers were measured for mixtures of varying surfactant concentrations. The double capillary technique was employed which enables exchange of the protein solution in the drop bulk by surfactant solution (sequential adsorption) or by pure buffer (washing out). The first protocol allows probing the influence of the surfactant on a pre-adsorbed protein layer thus studying the protein/surfactant interactions at the interface. The second protocol gives access to the residual values of Π and |E| measured after the washing out procedure thus bringing information about the process of protein desorption. The DoTAB/BLG complexes exhibit higher surface activity and higher resistance to desorption in comparison with those for the SDS/BLG complexes due to hydrophobization via electrostatic binding of surfactant molecules. The neutral DoTAB/BLG complexes achieve maximum elastic response of the mixed layer. Mixed BLG/surfactant layers at the water/oil interface are found to reach higher surface pressure and lower maximum dilational elasticity than those at the water/air surface. The sequential adsorption mode experiments and the desorption study reveal that binding of DoTAB to pre-adsorbed BLG globules is somehow restricted at the water/air surface in comparison with the case of complex formation in the solution bulk and subsequently adsorbed at the water/air surface. Maximum elasticity is achieved with washed out layers obtained after simultaneous adsorption, i.e. isolation of the most surface active DoTAB/BLG complex. These specific effects are much less pronounced at the W/H interface. Copyright © 2015 Elsevier Inc. All rights reserved.

How Socio-Emotional Support Affects Post-Compulsory Education Decisions in Rural China

ERIC Educational Resources Information Center

Yao, Haogen

2017-01-01

This study develops a sequential mixed model of Delphi-Propensity Score Matching to discuss how an NGO's socio-emotional support affects the decisions of dropout, work, and two types of upper secondary schooling in rural China. Data were collected from 6,298 students in 2012 after a subgroup of them were treated. The analysis shows that…

Construction workers working in musculoskeletal pain and engaging in leisure-time physical activity: Findings from a mixed-methods pilot study.

PubMed

Caban-Martinez, Alberto J; Lowe, Kincaid A; Herrick, Robert; Kenwood, Christopher; Gagne, Joshua J; Becker, Jamie F; Schneider, Scott P; Dennerlein, Jack T; Sorensen, Glorian

2014-07-01

While exercise has been shown to be beneficial for some musculoskeletal pain conditions, construction workers who are regularly burdened with musculoskeletal pain may engage less in leisure-time physical activity (LTPA) due to pain. In a small pilot study, we investigate how musculoskeletal pain may influence participation in LTPA among construction workers. A sequential explanatory mixed-methods design was employed using a jobsite-based survey (n = 43) among workers at two commercial construction sites and one focus group (n = 5). Over 93% of these construction workers reported engaging in LTPA and 70% reported musculoskeletal pain. Fifty-seven percent of workers who met either moderate or vigorous LTPA guidelines reported lower extremity pain (i.e., ankle, knee) compared with 21% of those who did not engage in either LTPA (P = 0.04). Focus group analyses indicate that workers felt they already get significant physical activity out of their job because they are "moving all the time and not sitting behind a desk." Workers also felt they "have no choice but to work through pain and discomfort [as the worker] needs to do anything to get the job done." Pilot study findings suggest that construction workers not only engage in either moderate or vigorous LTPA despite musculoskeletal pain but workers in pain engage in more LTPA than construction workers without pain. © 2014 Wiley Periodicals, Inc.

Is directly observed tuberculosis treatment strategy patient-centered? A mixed method study in Addis Ababa, Ethiopia

PubMed Central

Getahun, Belete; Nkosi, Zethu Zerish

2017-01-01

Introduction The directly observed treatment, short course (DOTS) strategy has been considered as an efficacious approach for better tuberculosis (TB) treatment adherence and outcome. However, its level of patient centerdness has not been studied and documented well. Hence, the study aimed to determine the level of patient centeredness’ of the DOTS. Method The study used explanatory sequential mixed method design in Addis Ababa, Ethiopia. The study employed an interviewer-administered questionnaire with 601 patients with TB, focus group discussions with 23 TB experts, and telephonic-interview with 25 persons lost to follow-up from TB treatment. Descriptive and multivariable analyses carried out for the quantitative data while thematic analysis was used for the qualitative data. Result Forty percent of patients with TB had not received patient-centered TB care (PC-TB care) with DOTS. Male gender (AOR = 0.45, 95% CI 0.3, 0.7), good communication (AOR = 3.2, 95%CI 1.6, 6.1), and health care providers as a treatment supporter (AOR = 3.4, 95% CI 2.1, 5.48) had significant associations with PC-TB care. All persons lost to follow-up and TB experts perceived that DOTS is merely patient-centered. The identified categories were patient preferences, treatment supporter choice, integration of DOTS with nutritional support, mental health, and transport services, provider’s commitment and communication skills. Conclusion DOTS is limited to provide patient-centered TB care. Hence, DOTS needs a model that enhances effectiveness towards patient centeredness of TB care. PMID:28763456

The effectiveness of recruitment strategies on general practitioner’s survey response rates – a systematic review

PubMed Central

2014-01-01

Background Low survey response rates in general practice are common and lead to loss of power, selection bias, unexpected budgetary constraints and time delays in research projects. Methods Objective: To assess the effectiveness of recruitment strategies aimed at increasing survey response rates among GPs. Design: Systematic review. Search methods: MEDLINE (OVIDSP, 1948-2012), EMBASE (OVIDSP, 1980-2012), Evidence Based Medicine Reviews (OVIDSP, 2012) and references of included papers were searched. Major search terms included GPs, recruitment strategies, response rates, and randomised controlled trials (RCT). Selection criteria: Cluster RCTs, RCTs and factorial trial designs that evaluate recruitment strategies aimed at increasing GP survey response rates. Data collection and analysis: Abstracts identified by the search strategy were reviewed and relevant articles were retrieved. Each full-text publication was examined to determine whether it met the predetermined inclusion criteria. Data extraction and study quality was assessed by using predetermined checklists. Results Monetary and nonmonetary incentives were more effective than no incentive with monetary incentives having a slightly bigger effect than nonmonetary incentives. Large incentives were more effective than small incentives, as were upfront monetary incentives compared to promised monetary incentives. Postal surveys were more effective than telephone or email surveys. One study demonstrated that sequentially mixed mode (online survey followed by a paper survey with a reminder) was more effective than an online survey or the combination of an online and paper survey sent similtaneously in the first mail out. Pre-contact with a phonecall from a peer, personalised packages, sending mail on Friday, and using registered mail also increased response rates in single studies. Pre-contact by letter or postcard almost reached statistical signficance. Conclusions GP survey response rates may improve by using the following strategies: monetary and nonmonetary incentives, larger incentives, upfront monetary incentives, postal surveys, pre-contact with a phonecall from a peer, personalised packages, sending mail on Friday, and using registered mail. Mail pre-contact may also improve response rates and have low costs. Improved reporting and further trials, including sequential mixed mode trials and social media, are required to determine the effectiveness of recruitment strategies on GPs' response rates to surveys. PMID:24906492

Integrating qualitative research methods into care improvement efforts within a learning health system: addressing antibiotic overuse.

PubMed

Munoz-Plaza, Corrine E; Parry, Carla; Hahn, Erin E; Tang, Tania; Nguyen, Huong Q; Gould, Michael K; Kanter, Michael H; Sharp, Adam L

2016-08-15

Despite reports advocating for integration of research into healthcare delivery, scant literature exists describing how this can be accomplished. Examples highlighting application of qualitative research methods embedded into a healthcare system are particularly needed. This article describes the process and value of embedding qualitative research as the second phase of an explanatory, sequential, mixed methods study to improve antibiotic stewardship for acute sinusitis. Purposive sampling of providers for in-depth interviews improved understanding of unwarranted antibiotic prescribing and elicited stakeholder recommendations for improvement. Qualitative data collection, transcription and constant comparative analyses occurred iteratively. Emerging themes and sub-themes identified primary drivers of unwarranted antibiotic prescribing patterns and recommendations for improving practice. These findings informed the design of a health system intervention to improve antibiotic stewardship for acute sinusitis. Core components of the intervention are also described. Qualitative research can be effectively applied in learning healthcare systems to elucidate quantitative results and inform improvement efforts.

Dual-mixed HIV-1 Coreceptor Tropism and HIV-Associated Neurocognitive Deficits

PubMed Central

Morris, Sheldon R.; Woods, Steven Paul; Deutsch, Reena; Little, Susan J.; Wagner, Gabriel; Morgan, Erin E.; Heaton, Robert K.; Letendre, Scott L.; Grant, Igor; Smith, Davey M.

2014-01-01

Background HIV coreceptor usage of CXCR4 (X4) is associated with decreased CD4+ T-cell counts and accelerated disease progression, but the role of X4 tropism in HIV-associated neurocognitive disorders (HAND) has not previously been described. Methods This longitudinal study evaluated data on 197 visits from 72 recently HIV-infected persons who had undergone up to 4 sequential neurocognitive assessments over a median of 160 days (IQR 138–192). Phenotypic tropism testing (Trofile ES, Monogram, Biosciences) was performed on stored blood samples. Multivariable mixed model repeated measures regression was used to determine the association between HAND and dual-mixed (DM) viral tropism, estimated duration of infection (EDI), HIV RNA, CD4 count and problematic methamphetamine use. Results Six subjects (8.3%) had dual mixed tropism (DM) at their first neurocognitive assessment and four converted to DM in subsequent sampling (for total of 10 DM) at a median EDI of 10.1 months (IQR 7.2–12.2). There were 44 (61.1%) subjects who demonstrated HAND on at least one study visit. HAND was associated with DM tropism (odds ratio 4.4, 95% CI 0.9–20.5) and shorter EDI (odds ratio 1.1 per month earlier, 95% CI 1.0–1.2). Conclusion This study found that recency of HIV-1 infection and the development of DM tropism may be associated with HAND in the relatively early stage of infection. Together these data suggest that viral interaction with cellular receptors may play an important role in the early manifestation of HAND. PMID:24078557

The learning of aquaponics practice in university

NASA Astrophysics Data System (ADS)

Agustina, T. W.; Rustaman, N. Y.; Riandi; Purwianingsih, W.

2018-05-01

This study aims to obtain a description of the perfomance capabilities of aquaponic technology and the assessment of product and packaging of harvest kale. The aquaponic practice used a STREAM (Science Technology Religion Art Matematics) approach. The method was explanatory sequential mixed method. The research was conducted on one class of Biology Education students in 6th semester. The sample was chosen purposively with 49 students. The study instruments are student worksheet, observation sheet, rubric performance and product assessment, interview sheet and field notes. The indicator of performance rubrics on the manufacture of aquaponic technology consisted of the product rubric, cultivation criteria and packing method of kale. The interview rubric is in the form of student constraints on the manufacture of aquaponics. Based on the results, most students have performance in designing technology that is categorized as enough up to good. Almost all students produce a very good kale harvest. Most of the students produce kale packaging products that are categorized as enough. The implications of this research are the learning of aquaponic with the STREAM approach can equip student’s performance and product capabilities.

[Nutritional self-care promotion in community-dwelling older people: a protocol of mixed method research].

PubMed

Raffaele, Barbara; Matarese, Maria; Piredda, Michela; De Marinis, Maria Grazia

2016-01-01

To describe a research protocol designed to promote nutritional self-care in older people. The aims of the research are: a) to evaluate the effectiveness of a nutritional education intervention in changing knowledge, attitudes, and behaviors; b) to describe the nutritional self-care ability and activities; c) to identify the promoting factors and barriers that influence the changes in nutritional knowledge, behaviors and attitudes in home-dwelling older people. Sequential explanatory mixed method design. The study will enroll 50 people aged 65 years and over. In the first quantitative phase, a pre-test and post-test design will be used to deliver a nutritional intervention aimed to change knowledge, behaviors and attitudes toward nutrition. Using the quantitative study results, the qualitative study phase will be conducted by interviews in sub-groups of older people. In a third phase, the quantitative and qualitative study results will be integrated. Quantitative data will be analyzed using descriptive and inferential statistics and qualitative data will be analyzed through content analysis. The study will provide new knowledge on nutritional self-care in home-dwelling older adults and the factors promoting nutritional self-care. Nutritional self-care promotion is of pivotal importance for the nursing care provided to home-dwelling older people. Educational programs aimed at the maintenance of proper nutrition in the older adults may reduce malnutrition and the related diseases. Nutrition educational programs should be based on knowledge derived from research to tailor individualized nutritional interventions and to realize effective educational programs.

Is directly observed tuberculosis treatment strategy patient-centered? A mixed method study in Addis Ababa, Ethiopia.

PubMed

Getahun, Belete; Nkosi, Zethu Zerish

2017-01-01

The directly observed treatment, short course (DOTS) strategy has been considered as an efficacious approach for better tuberculosis (TB) treatment adherence and outcome. However, its level of patient centerdness has not been studied and documented well. Hence, the study aimed to determine the level of patient centeredness' of the DOTS. The study used explanatory sequential mixed method design in Addis Ababa, Ethiopia. The study employed an interviewer-administered questionnaire with 601 patients with TB, focus group discussions with 23 TB experts, and telephonic-interview with 25 persons lost to follow-up from TB treatment. Descriptive and multivariable analyses carried out for the quantitative data while thematic analysis was used for the qualitative data. Forty percent of patients with TB had not received patient-centered TB care (PC-TB care) with DOTS. Male gender (AOR = 0.45, 95% CI 0.3, 0.7), good communication (AOR = 3.2, 95%CI 1.6, 6.1), and health care providers as a treatment supporter (AOR = 3.4, 95% CI 2.1, 5.48) had significant associations with PC-TB care. All persons lost to follow-up and TB experts perceived that DOTS is merely patient-centered. The identified categories were patient preferences, treatment supporter choice, integration of DOTS with nutritional support, mental health, and transport services, provider's commitment and communication skills. DOTS is limited to provide patient-centered TB care. Hence, DOTS needs a model that enhances effectiveness towards patient centeredness of TB care.

A method for simultaneously counterbalancing condition order and assignment of stimulus materials to conditions.

PubMed

Zeelenberg, René; Pecher, Diane

2015-03-01

Counterbalanced designs are frequently used in the behavioral sciences. Studies often counterbalance either the order in which conditions are presented in the experiment or the assignment of stimulus materials to conditions. Occasionally, researchers need to simultaneously counterbalance both condition order and stimulus assignment to conditions. Lewis (1989; Behavior Research Methods, Instruments, & Computers 25:414-415, 1993) presented a method for constructing Latin squares that fulfill these requirements. The resulting Latin squares counterbalance immediate sequential effects, but not remote sequential effects. Here, we present a new method for generating Latin squares that simultaneously counterbalance both immediate and remote sequential effects and assignment of stimuli to conditions. An Appendix is provided to facilitate implementation of these Latin square designs.

A high-throughput microtiter plate based method for the determination of peracetic acid and hydrogen peroxide.

PubMed

Putt, Karson S; Pugh, Randall B

2013-01-01

Peracetic acid is gaining usage in numerous industries who have found a myriad of uses for its antimicrobial activity. However, rapid high throughput quantitation methods for peracetic acid and hydrogen peroxide are lacking. Herein, we describe the development of a high-throughput microtiter plate based assay based upon the well known and trusted titration chemical reactions. The adaptation of these titration chemistries to rapid plate based absorbance methods for the sequential determination of hydrogen peroxide specifically and the total amount of peroxides present in solution are described. The results of these methods were compared to those of a standard titration and found to be in good agreement. Additionally, the utility of the developed method is demonstrated through the generation of degradation curves of both peracetic acid and hydrogen peroxide in a mixed solution.

A High-Throughput Microtiter Plate Based Method for the Determination of Peracetic Acid and Hydrogen Peroxide

PubMed Central

Putt, Karson S.; Pugh, Randall B.

2013-01-01

Peracetic acid is gaining usage in numerous industries who have found a myriad of uses for its antimicrobial activity. However, rapid high throughput quantitation methods for peracetic acid and hydrogen peroxide are lacking. Herein, we describe the development of a high-throughput microtiter plate based assay based upon the well known and trusted titration chemical reactions. The adaptation of these titration chemistries to rapid plate based absorbance methods for the sequential determination of hydrogen peroxide specifically and the total amount of peroxides present in solution are described. The results of these methods were compared to those of a standard titration and found to be in good agreement. Additionally, the utility of the developed method is demonstrated through the generation of degradation curves of both peracetic acid and hydrogen peroxide in a mixed solution. PMID:24260173

A Bayesian sequential design with adaptive randomization for 2-sided hypothesis test.

PubMed

Yu, Qingzhao; Zhu, Lin; Zhu, Han

2017-11-01

Bayesian sequential and adaptive randomization designs are gaining popularity in clinical trials thanks to their potentials to reduce the number of required participants and save resources. We propose a Bayesian sequential design with adaptive randomization rates so as to more efficiently attribute newly recruited patients to different treatment arms. In this paper, we consider 2-arm clinical trials. Patients are allocated to the 2 arms with a randomization rate to achieve minimum variance for the test statistic. Algorithms are presented to calculate the optimal randomization rate, critical values, and power for the proposed design. Sensitivity analysis is implemented to check the influence on design by changing the prior distributions. Simulation studies are applied to compare the proposed method and traditional methods in terms of power and actual sample sizes. Simulations show that, when total sample size is fixed, the proposed design can obtain greater power and/or cost smaller actual sample size than the traditional Bayesian sequential design. Finally, we apply the proposed method to a real data set and compare the results with the Bayesian sequential design without adaptive randomization in terms of sample sizes. The proposed method can further reduce required sample size. Copyright © 2017 John Wiley & Sons, Ltd.

Multi-Target Tracking via Mixed Integer Optimization

DTIC Science & Technology

2016-05-13

solving these two problems separately, however few algorithms attempt to solve these simultaneously and even fewer utilize optimization. In this paper we...introduce a new mixed integer optimization (MIO) model which solves the data association and trajectory estimation problems simultaneously by minimizing...Kalman filter [5], which updates the trajectory estimates before the algorithm progresses forward to the next scan. This process repeats sequentially

Sequential causal inference: Application to randomized trials of adaptive treatment strategies

PubMed Central

Dawson, Ree; Lavori, Philip W.

2009-01-01

SUMMARY Clinical trials that randomize subjects to decision algorithms, which adapt treatments over time according to individual response, have gained considerable interest as investigators seek designs that directly inform clinical decision making. We consider designs in which subjects are randomized sequentially at decision points, among adaptive treatment options under evaluation. We present a sequential method to estimate the comparative effects of the randomized adaptive treatments, which are formalized as adaptive treatment strategies. Our causal estimators are derived using Bayesian predictive inference. We use analytical and empirical calculations to compare the predictive estimators to (i) the ‘standard’ approach that allocates the sequentially obtained data to separate strategy-specific groups as would arise from randomizing subjects at baseline; (ii) the semi-parametric approach of marginal mean models that, under appropriate experimental conditions, provides the same sequential estimator of causal differences as the proposed approach. Simulation studies demonstrate that sequential causal inference offers substantial efficiency gains over the standard approach to comparing treatments, because the predictive estimators can take advantage of the monotone structure of shared data among adaptive strategies. We further demonstrate that the semi-parametric asymptotic variances, which are marginal ‘one-step’ estimators, may exhibit significant bias, in contrast to the predictive variances. We show that the conditions under which the sequential method is attractive relative to the other two approaches are those most likely to occur in real studies. PMID:17914714

Numerical study on the sequential Bayesian approach for radioactive materials detection

NASA Astrophysics Data System (ADS)

Qingpei, Xiang; Dongfeng, Tian; Jianyu, Zhu; Fanhua, Hao; Ge, Ding; Jun, Zeng

2013-01-01

A new detection method, based on the sequential Bayesian approach proposed by Candy et al., offers new horizons for the research of radioactive detection. Compared with the commonly adopted detection methods incorporated with statistical theory, the sequential Bayesian approach offers the advantages of shorter verification time during the analysis of spectra that contain low total counts, especially in complex radionuclide components. In this paper, a simulation experiment platform implanted with the methodology of sequential Bayesian approach was developed. Events sequences of γ-rays associating with the true parameters of a LaBr3(Ce) detector were obtained based on an events sequence generator using Monte Carlo sampling theory to study the performance of the sequential Bayesian approach. The numerical experimental results are in accordance with those of Candy. Moreover, the relationship between the detection model and the event generator, respectively represented by the expected detection rate (Am) and the tested detection rate (Gm) parameters, is investigated. To achieve an optimal performance for this processor, the interval of the tested detection rate as a function of the expected detection rate is also presented.

Symptom management in complex post-traumatic stress disorder (ICD-11), view and experience of patients and their relatives: a mixed methods approach (Research Proposal).

PubMed

Stadtmann, Manuel P; Maercker, Andreas; Binder, Jochen; Schnepp, Wilfried

2017-09-07

Using the framework of IDC-11, complex post-traumatic stress disorder will be diagnosed using the core criteria of a post-traumatic stress disorder and the presence of at least one symptom from the following three domains: symptoms of emotional dysregulation, negative self-concept, and problems in interpersonal relationships. In the literature, these symptoms are discussed as a common reason for seeking treatment. The symptoms can influence and impair the quality of life. This article describes a mixed methods study with a sequential exploratory design. The aim is to describe specific patient characteristics, levels of symptom burden and perspectives of adult inpatients and to describe the experiences, views and needs of patients' relatives. The study will also investigate facilitators of and barriers to symptom management. The research will be conducted in four phases. The first phase will assess patients' symptom burdens. The second phase will use semi-structured interviews to explore attitudes to symptom management and perceptions of patients and their relatives. The third phase will statistically explore hypotheses generated after the qualitative interviews. The fourth phase will mix the quantitative and qualitative results and interpret critically. The present study will add new results to the growing literature on complex post-traumatic stress disorder. These results could serve as the basis for further research into the development of interventions to improve symptom management. Trial registration Ethical approval has been obtained from the Swiss cantonal ethic commission (Nr. 201500096). This research was also registered to the World Health Organization Clinical Trials Search Portal through the German Clinical Trial Register, Trial DRKS00012268 (21/04/2017).

Utilising a collective case study system theory mixed methods approach: a rural health example.

PubMed

Adams, Robyn; Jones, Anne; Lefmann, Sophie; Sheppard, Lorraine

2014-07-28

Insight into local health service provision in rural communities is limited in the literature. The dominant workforce focus in the rural health literature, while revealing issues of shortage of maldistribution, does not describe service provision in rural towns. Similarly aggregation of data tends to render local health service provision virtually invisible. This paper describes a methodology to explore specific aspects of rural health service provision with an initial focus on understanding rurality as it pertains to rural physiotherapy service provision. A system theory-case study heuristic combined with a sequential mixed methods approach to provide a framework for both quantitative and qualitative exploration across sites. Stakeholder perspectives were obtained through surveys and in depth interviews. The investigation site was a large area of one Australian state with a mix of rural, regional and remote communities. 39 surveys were received from 11 locations within the investigation site and 19 in depth interviews were conducted. Stakeholder perspectives of rurality and workforce numbers informed the development of six case types relevant to the exploration of rural physiotherapy service provision. Participant perspective of rurality often differed with the geographical classification of their location. The numbers of onsite colleagues and local access to health services contributed to participant perceptions of rurality. The complexity of understanding the concept of rurality was revealed by interview participants when providing their perspectives about rural physiotherapy service provision. Dual measures, such as rurality and workforce numbers, provide more relevant differentiation of sites to explore specific services, such rural physiotherapy service provision, than single measure of rurality as defined by geographic classification. The system theory-case study heuristic supports both qualitative and quantitative exploration in rural health services research.

Trial Sequential Methods for Meta-Analysis

ERIC Educational Resources Information Center

Kulinskaya, Elena; Wood, John

2014-01-01

Statistical methods for sequential meta-analysis have applications also for the design of new trials. Existing methods are based on group sequential methods developed for single trials and start with the calculation of a required information size. This works satisfactorily within the framework of fixed effects meta-analysis, but conceptual…

The effectiveness of peer mentoring in promoting a positive transition to higher education for first-year undergraduate students: a mixed methods systematic review protocol.

PubMed

Carragher, Jean; McGaughey, Jennifer

2016-04-22

The global transfer of nursing and midwifery education to higher education institutes has led to student nurses and midwives experiencing challenges previously faced by traditional third-level students, including isolation, loneliness, financial difficulties and academic pressure. These challenges can contribute to increased stress and anxiety levels which may be detrimental to the successful transition to higher education, thus leading to an increase in attrition rates. Peer mentoring as an intervention has been suggested to be effective in supporting students in the transition to third-level education through enhancing a sense of belongingness and improving student satisfaction, engagement and retention rates. This proposed systematic review aims to determine the effectiveness of peer mentoring in enhancing levels of student engagement, sense of belonging and overall satisfaction of first-year undergraduate students following transition into higher education. MEDLINE, Web of Knowledge, ProQuest, Embase, CINAHL, ERIC, PsycINFO and CENTRAL databases will be searched for qualitative, quantitative and mixed methods studies on the implementation of peer assessment strategies in higher education institutes (HEIs) or universities for full-time, first-year adult students (>17 years). Included studies will be limited to the English language. The quality of included studies will be assessed using a validated Mixed Methods Appraisal Tool (MMAT). The findings will be presented as a narrative synthesis or meta-analysis as appropriate following sequential explanatory synthesis. The review will provide clear, non-biased evidence-based guidance to all third-level educators on the effectiveness of peer-mentoring programmes for first-year undergraduates. The review is necessary to help establish which type of peer mentoring is most effective. The evidence from qualitative and quantitative studies drawn from the international literature will be utilised to illustrate the best way to implement and evaluate peer mentoring as an effective intervention and will be useful in guiding future research and practice in this area. These findings may be applied internationally across all disciplines.

Physical properties of sequential interpenetrating polymer networks produced from canola oil-based polyurethane and poly(methyl methacrylate).

PubMed

Kong, Xiaohua; Narine, Suresh S

2008-05-01

Sequential interpenetrating polymer networks (IPNs) were prepared using polyurethane (PUR) synthesized from canola oil-based polyol with terminal primary functional groups and poly(methyl methacrylate) (PMMA). The properties of the material were evaluated by dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), and modulated differential scanning calorimetry (MDSC), as well as tensile properties measurements. The morphology of the IPNs was investigated using scanning electron microscopy (SEM) and MDSC. A five-phase morphology, that is, sol phase, PUR-rich phase, PUR-rich interphase, PMMA-rich interphase, and PMMA-rich phase, was observed for all the IPNs by applying a new quantitative method based on the measurement of the differential of reversing heat capacity versus temperature from MDSC, although not confirmed by SEM, most likely due to resolution restrictions. NCO/OH molar ratios (cross-linking density) and compositional variations of PUR/PMMA both affected the thermal properties and phase behaviors of the IPNs. Higher degrees of mixing occurred for the IPN with higher NCO/OH molar ratio (2.0/1.0) at PUR concentration of 25 wt %, whereas for the IPN with lower NCO/OH molar ratio (1.6/1.0), higher degrees of mixing occurred at PUR concentration of 35 wt %. The mechanical properties of the IPNs were superior to those of the constituent polymers due to the finely divided rubber and plastic combination structures in these IPNs.

Assessment of sequential same arm agreement of blood pressure measurements by a CVProfilor DO-2020 versus a Baumanometer mercury sphygmomanometer.

PubMed

Prisant, L M; Resnick, L M; Hollenberg, S M

2001-06-01

The aim of this study was to assess the accuracy of sequential same arm blood pressure measurement by the mercury sphygmomanometer with the oscillometric blood pressure measurements from a device that also determines arterial elasticity. A prospective, multicentre, clinical study evaluated sequential same arm blood pressure measurements, using a mercury sphygmomanometer (Baumanometer, W. A. Baum Co., Inc., Copiague, New York, USA) and an oscillometric non-invasive device that calculates arterial elasticity (CVProfilor DO-2020 Cardiovascular Profiling System, Hypertension Diagnostics, Inc., Eagan, Minnesota, USA). Blood pressure was measured supine in triplicate, 3 min apart in a randomized sequence after a period of rest. The study population of 230 normotensive and hypertensive subjects included 57% females, 51% Caucasians, and 33% African Americans. The mean difference between test methods of systolic blood pressure, diastolic blood pressure, and heart rate was -3.2 +/- 6.9 mmHg, +0.8 +/- 5.9 mmHg, and +1.0 +/- 5.7 beats/minute. For systolic and diastolic blood pressure, 60.9 and 70.4% of sequential measurements by each method were within +/- 5 mmHg. Few or no points fell beyond the mean +/- 2 standard deviations lines for each cuff bladder size. Sequential same arm measurements of the CVProfilor DO-2020 Cardiovascular Profiling System measures blood pressure by an oscillometric method (dynamic linear deflation) with reasonable agreement with a mercury sphygmomanometer.

Quantitative cervical vertebral maturation assessment in adolescents with normal occlusion: a mixed longitudinal study.

PubMed

Chen, Li-Li; Xu, Tian-Min; Jiang, Jiu-Hui; Zhang, Xing-Zhong; Lin, Jiu-Xiang

2008-12-01

The purpose of this study was to establish a quantitative cervical vertebral maturation (CVM) system for adolescents with normal occlusion. Mixed longitudinal data were used. The subjects included 87 children and adolescents from 8 to 18 years old with normal occlusion (32 boys, 55 girls) selected from 901 candidates. Sequential lateral cephalograms and hand-wrist films were taken once a year for 6 years. The lateral cephalograms of all subjects were divided into 11 maturation groups according to the Fishman skeletal maturity indicators. The morphologic characteristics of the second, third, and fourth cervical vertebrae at 11 developmental stages were measured and analyzed. Three characteristic parameters (H4/W4, AH3/PH3, @2) were selected to determine the classification of CVM. With 3 morphologic variables, the quantitative CVM system including 4 maturational stages was established. An equation that can accurately estimate the maturation of the cervical vertebrae was established: CVM stage=-4.13+3.57xH4/W4+4.07xAH3/PH3+0.03x@2. The quantitative CVM method is an efficient, objective, and relatively simple approach to assess the level of skeletal maturation during adolescence.

Links between Adolescent Athletes’ Prosocial Behavior and Relationship with Parents: A Mixed Methods Study

PubMed Central

Lisinskienė, Aušra

2018-01-01

Adolescent relationships with parents are of the highest importance. The relationships likely reflect the nature of internal working models in youth sport that may well function as a psychological template during the construction of youth prosocial behavior. However, researchers’ focus to date has concerned specific aspects of parental practices in child-based sporting activities. There is a lack of research covering parent-athlete interpersonal relationships concerned with how the relationships affect adolescent prosocial behavior. The purpose of this mixed methods explanatory sequential study was to examine teenage athletes’ prosocial behavior and their relationships with parents. To achieve our purpose, we obtained quantitative data from 1348 athletes and non-athletes (ages 12–16), and qualitative data from 12 adolescent athletes and 12 youth sports parents. In the quantitative phase, we assessed adolescent prosocial behavior regarding the following six forms of prosocial behavior: public, anonymous, dire, compliant, altruistic and emotional. In the qualitative follow-up, three themes emerged from the adolescent athlete’s perspective: (1) sport as an escape; (2) parent-child relationships in youth sports; (3) adolescents’ desired behavior. Three themes emerged from the parental perspective: (1) sport as protection and as a school of life; (2) painful decisions to release a child; (3) understanding adolescent behavior. We found protection from delinquent behavior and increased prosocial behavior with securely attached young athletes who are actively involved in sports. PMID:29910308

Testing constrained sequential dominance models of neutrinos

NASA Astrophysics Data System (ADS)

Björkeroth, Fredrik; King, Stephen F.

2015-12-01

Constrained sequential dominance (CSD) is a natural framework for implementing the see-saw mechanism of neutrino masses which allows the mixing angles and phases to be accurately predicted in terms of relatively few input parameters. We analyze a class of CSD(n) models where, in the flavour basis, two right-handed neutrinos are dominantly responsible for the ‘atmospheric’ and ‘solar’ neutrino masses with Yukawa couplings to ({ν }e,{ν }μ ,{ν }τ ) proportional to (0,1,1) and (1,n,n-2), respectively, where n is a positive integer. These coupling patterns may arise in indirect family symmetry models based on A 4. With two right-handed neutrinos, using a χ 2 test, we find a good agreement with data for CSD(3) and CSD(4) where the entire Pontecorvo-Maki-Nakagawa-Sakata mixing matrix is controlled by a single phase η, which takes simple values, leading to accurate predictions for mixing angles and the magnitude of the oscillation phase | {δ }{CP}| . We carefully study the perturbing effect of a third ‘decoupled’ right-handed neutrino, leading to a bound on the lightest physical neutrino mass {m}1{{≲ }}1 meV for the viable cases, corresponding to a normal neutrino mass hierarchy. We also discuss a direct link between the oscillation phase {δ }{CP} and leptogenesis in CSD(n) due to the same see-saw phase η appearing in both the neutrino mass matrix and leptogenesis.

Timing the Mode Switch in a Sequential Mixed-Mode Survey: An Experimental Evaluation of the Impact on Final Response Rates, Key Estimates, and Costs

PubMed Central

Wagner, James; Schroeder, Heather M.; Piskorowski, Andrew; Ursano, Robert J.; Stein, Murray B.; Heeringa, Steven G.; Colpe, Lisa J.

2017-01-01

Mixed-mode surveys need to determine a number of design parameters that may have a strong influence on costs and errors. In a sequential mixed-mode design with web followed by telephone, one of these decisions is when to switch modes. The web mode is relatively inexpensive but produces lower response rates. The telephone mode complements the web mode in that it is relatively expensive but produces higher response rates. Among the potential negative consequences, delaying the switch from web to telephone may lead to lower response rates if the effectiveness of the prenotification contact materials is reduced by longer time lags, or if the additional e-mail reminders to complete the web survey annoy the sampled person. On the positive side, delaying the switch may decrease the costs of the survey. We evaluate these costs and errors by experimentally testing four different timings (1, 2, 3, or 4 weeks) for the mode switch in a web–telephone survey. This experiment was conducted on the fourth wave of a longitudinal study of the mental health of soldiers in the U.S. Army. We find that the different timings of the switch in the range of 1–4 weeks do not produce differences in final response rates or key estimates but longer delays before switching do lead to lower costs. PMID:28943717

Evaluating quality of patient care communication in integrated care settings: a mixed method approach.

PubMed

Gulmans, J; Vollenbroek-Hutten, M M R; Van Gemert-Pijnen, J E W C; Van Harten, W H

2007-10-01

Owing to the involvement of multiple professionals from various institutions, integrated care settings are prone to suboptimal patient care communication. To assure continuity, communication gaps should be identified for targeted improvement initiatives. However, available assessment methods are often one-sided evaluations not appropriate for integrated care settings. We developed an evaluation approach that takes into account the multiple communication links and evaluation perspectives inherent to these settings. In this study, we describe this approach, using the integrated care setting of Cerebral Palsy as illustration. The approach follows a three-step mixed design in which the results of each step are used to mark out the subsequent step's focus. The first step patient questionnaire aims to identify quality gaps experienced by patients, comparing their expectancies and experiences with respect to patient-professional and inter-professional communication. Resulting gaps form the input of in-depth interviews with a subset of patients to evaluate underlying factors of ineffective communication. Resulting factors form the input of the final step's focus group meetings with professionals to corroborate and complete the findings. By combining methods, the presented approach aims to minimize limitations inherent to the application of single methods. The comprehensiveness of the approach enables its applicability in various integrated care settings. Its sequential design allows for in-depth evaluation of relevant quality gaps. Further research is needed to evaluate the approach's feasibility in practice. In our subsequent study, we present the results of the approach in the integrated care setting of children with Cerebral Palsy in three Dutch care regions.

Food and beverage price discounts to improve health in remote Aboriginal communities: mixed method evaluation of a natural experiment.

PubMed

Ferguson, Megan; O'Dea, Kerin; Holden, Stacey; Miles, Eddie; Brimblecombe, Julie

2017-02-01

Retrospectively evaluate food price discounts in remote Aboriginal community stores. Four price discount strategies of 10% were designed in 2010, aiming to influence grocery, fruit, vegetables and diet soft-drink sales. This natural experiment across a group of stores was evaluated using an explanatory, sequential mixed method design through analysis of store point-of-sale, document, observation and interview data. The outcome was measured by change in: 1) percentage of grocery sales to total food and beverage; 2) fruit and vegetable sales; and 3) diet soft-drink sales. Qualitative data enabled the interpretation of outcomes through understanding perceived success and benefits, and enablers and barriers to implementation. Eighteen community stores and 54 informants participated. While targeted price discounts were considered important to improving health, no discernible effect was evident, due to inadequate design and communication of discount promotion, and probably inadequate magnitude of discount. Strategy impact on food and beverage sales was limited by promotion and magnitude of discount. Implication for Public Health: This study demonstrates key factors and commitment required to design, communicate, implement and monitor strategies to improve health in this challenging remote retail context. Evaluation of natural experiments can contribute evidence to policy-making. © 2016 The Authors.

Conflict resolution patterns and violence perpetration in adolescent couples: A gender-sensitive mixed-methods approach.

PubMed

Fernet, Mylène; Hébert, Martine; Paradis, Alison

2016-06-01

This study used a sequential two-phase explanatory design. The first phase of this mixed-methods design aimed to explore conflict resolution strategies in adolescent dating couples, and the second phase to document, from both the perspective of the individual and of the couple, dyadic interaction patterns distinguishing youth inflicting dating violence from those who do not. A sample of 39 heterosexual couples (mean age 17.8 years) participated in semi-structured interviews and were observed during a 45 min dyadic interaction. At phase 1, qualitative analysis revealed three main types of conflict resolution strategies: 1) negotiating expectations and individual needs; 2) avoiding conflicts or their resolution; 3) imposing personal needs and rules through the use of violence. At phase 2, we focused on couples with conflictive patterns. Results indicate that couples who inflict violence differ from nonviolent couples by their tendency to experience conflicts when in disagreement and to resort to negative affects as a resolution strategy. In addition, while at an individual level, they show a tendency to withdraw from conflict and to use less positive affect, at a dyadic level they present less symmetry. Results offer important insights for prevention programs. Copyright © 2016. Published by Elsevier Ltd.

Comparison of penalty functions on a penalty approach to mixed-integer optimization

NASA Astrophysics Data System (ADS)

Francisco, Rogério B.; Costa, M. Fernanda P.; Rocha, Ana Maria A. C.; Fernandes, Edite M. G. P.

2016-06-01

In this paper, we present a comparative study involving several penalty functions that can be used in a penalty approach for globally solving bound mixed-integer nonlinear programming (bMIMLP) problems. The penalty approach relies on a continuous reformulation of the bMINLP problem by adding a particular penalty term to the objective function. A penalty function based on the `erf' function is proposed. The continuous nonlinear optimization problems are sequentially solved by the population-based firefly algorithm. Preliminary numerical experiments are carried out in order to analyze the quality of the produced solutions, when compared with other penalty functions available in the literature.

Airborne Lidar measurements of aerosols, mixed layer heights, and ozone during the 1980 PEPE/NEROS summer field experiment

NASA Technical Reports Server (NTRS)

Browell, E. V.; Shipley, S. T.; Butler, C. F.; Ismail, S.

1985-01-01

A detailed summary of the NASA Ultraviolet Differential Absorption Lidar (UV DIAL) data archive obtained during the EPA Persistent Elevated Pollution Episode/Northeast Regional Oxidant Study (PEPE/NEROS) Summer Field Experiment Program (July through August 1980) is presented. The UV dial data set consists of remote measurements of mixed layer heights, aerosol backscatter cross sections, and sequential ozone profiles taken during 14 long-range flights onboard the NASA Wallops Flight Center Electra aircraft. These data are presented in graphic and tabular form, and they have been submitted to the PEPE/NEROS data archive on digital magnetic tape. The derivation of mixing heights and ozone profiles from UV Dial signals is discussed, and detailed intercomparisons with measurements obtained by in situ sensors are presented.

Development of life story experience (LSE) scales for migrant dentists in Australia: a sequential qualitative-quantitative study.

PubMed

Balasubramanian, M; Spencer, A J; Short, S D; Watkins, K; Chrisopoulos, S; Brennan, D S

2016-09-01

The integration of qualitative and quantitative approaches introduces new avenues to bridge strengths, and address weaknesses of both methods. To develop measure(s) for migrant dentist experiences in Australia through a mixed methods approach. The sequential qualitative-quantitative design involved first the harvesting of data items from qualitative study, followed by a national survey of migrant dentists in Australia. Statements representing unique experiences in migrant dentists' life stories were deployed the survey questionnaire, using a five-point Likert scale. Factor analysis was used to examine component factors. Eighty-two statements from 51 participants were harvested from the qualitative analysis. A total of 1,022 of 1,977 migrant dentists (response rate 54.5%) returned completed questionnaires. Factor analysis supported an initial eight-factor solution; further scale development and reliability analysis led to five scales with a final list of 38 life story experience (LSE) items. Three scales were based on home country events: health system and general lifestyle concerns (LSE1; 10 items), society and culture (LSE4; 4 items) and career development (LSE5; 4 items). Two scales included migrant experiences in Australia: appreciation towards Australian way of life (LSE2; 13 items) and settlement concerns (LSE3; 7 items). The five life story experience scales provided necessary conceptual clarity and empirical grounding to explore migrant dentist experiences in Australia. Being based on original migrant dentist narrations, these scales have the potential to offer in-depth insights for policy makers and support future research on dentist migration. Copyright© 2016 Dennis Barber Ltd

Reducing the blame culture through clinical audit in nuclear medicine: a mixed methods study

PubMed Central

Ross, P; Hubert, J

2017-01-01

Objectives To identify the barriers and facilitators of doctors’ engagement with clinical audit and to explore how and why these factors influenced doctors’ decisions to engage with the NHS National Clinical Audit Programme. Design A single-embedded case study. Mixed methods sequential approach with explorative pilot study and follow-up survey. Pilot study comprised 13 semi-structured interviews with purposefully selected consultant doctors over a six-month period. Interview data coded and analysed using directed thematic content analysis with themes compared against the study’s propositions. Themes derived from the pilot study informed the online survey question items. Exploratory factor analysis using STATA and descriptive statistical methods applied to summarise findings. Data triangulation techniques used to corroborate and validate findings across the different methodological techniques. Setting NHS National PET-CT Clinical Audit Programme. Participants Doctors reporting on the Audit Programme. Main Outcome measures Extent of engagement with clinical audit, factors that influence engagement with clinical audit. Results Online survey: 58/59 doctors responded (98.3%). Audit was found to be initially threatening (79%); audit was reassuring (85%); audit helped validate professional competence (93%); participation in audit improved reporting skills (76%). Three key factors accounted for 97.6% of the variance in survey responses: (1) perception of audit’s usefulness, (2) a common purpose, (3) a supportive blame free culture of trust. Factor 1 influenced medical engagement most. Conclusions The study documents performance feedback as a key facilitator of medical engagement with clinical audit. It found that medical engagement with clinical audit was associated with reduced levels of professional anxiety and higher levels of perceived self-efficacy. PMID:28210493

Healthcare students' experiences of an interprofessional, student-led neuro-rehabilitation community-based clinic.

PubMed

Gustafsson, Louise; Hutchinson, Laura; Theodoros, Deborah; Williams, Katrina; Copley, Anna; Fagan, Amy; Desha, Laura

2016-01-01

Student-led clinics are becoming more prominent as educators seek alternate models of clinical education for health professionals. The purpose of this study was to evaluate healthcare students' experiences of an interprofessional student-led clinic for clients with neurological conditions. Thirteen students representing occupational therapy, physiotherapy, and speech pathology were recruited for the study. A sequential mixed-methods evaluation was employed and the results from the Interprofessional Education Scale and focus group revealed that the students experienced positive perceptions of working collaboratively with other professions, forming good relationships with others, as well as an increased respect for the roles of other professions. The findings suggest that providing a capstone opportunity, where students can work as part of an interprofessional team with a real client, in a format they may come across in future clinical practice, may be beneficial in providing them with essential interprofessional skills as new graduate health professionals.

Using a Household Food Inventory to Assess the Availability of Traditional Vegetables among Resettled African Refugees

PubMed Central

Gichunge, Catherine; Somerset, Shawn; Harris, Neil

2016-01-01

A cross-sectional sequential explanatory mixed methods study was conducted among household food preparers to examine the association between home availability and consumption of traditional vegetables among resettled African refugees living in Queensland, Australia. Home availability of traditional African vegetables was associated with age, having a vegetable garden, employment status, and having a supermarket in the local neighborhood. Food preparers from homes with low vegetable availability were less likely to consume the recommended number of vegetable servings. Barriers faced in the food environment included language, lack of availability of traditional vegetables and lack of transport. All of these aspects contributed to the study findings that both individual and food environment characteristics may play a role in access to and availability of food and vegetable consumption of resettled refugees. Consumption of traditional foods among the resettled refugees continues post resettlement. PMID:26797623

Using a Household Food Inventory to Assess the Availability of Traditional Vegetables among Resettled African Refugees.

PubMed

Gichunge, Catherine; Somerset, Shawn; Harris, Neil

2016-01-18

A cross-sectional sequential explanatory mixed methods study was conducted among household food preparers to examine the association between home availability and consumption of traditional vegetables among resettled African refugees living in Queensland, Australia. Home availability of traditional African vegetables was associated with age, having a vegetable garden, employment status, and having a supermarket in the local neighborhood. Food preparers from homes with low vegetable availability were less likely to consume the recommended number of vegetable servings. Barriers faced in the food environment included language, lack of availability of traditional vegetables and lack of transport. All of these aspects contributed to the study findings that both individual and food environment characteristics may play a role in access to and availability of food and vegetable consumption of resettled refugees. Consumption of traditional foods among the resettled refugees continues post resettlement.

Sequential biases in accumulating evidence

PubMed Central

Huggins, Richard; Dogo, Samson Henry

2015-01-01

Whilst it is common in clinical trials to use the results of tests at one phase to decide whether to continue to the next phase and to subsequently design the next phase, we show that this can lead to biased results in evidence synthesis. Two new kinds of bias associated with accumulating evidence, termed ‘sequential decision bias’ and ‘sequential design bias’, are identified. Both kinds of bias are the result of making decisions on the usefulness of a new study, or its design, based on the previous studies. Sequential decision bias is determined by the correlation between the value of the current estimated effect and the probability of conducting an additional study. Sequential design bias arises from using the estimated value instead of the clinically relevant value of an effect in sample size calculations. We considered both the fixed‐effect and the random‐effects models of meta‐analysis and demonstrated analytically and by simulations that in both settings the problems due to sequential biases are apparent. According to our simulations, the sequential biases increase with increased heterogeneity. Minimisation of sequential biases arises as a new and important research area necessary for successful evidence‐based approaches to the development of science. © 2015 The Authors. Research Synthesis Methods Published by John Wiley & Sons Ltd. PMID:26626562

Comparison of peer-tutoring learning model through problem-solving approach and traditional learning model on the cognitive ability of grade 10 students at SMKN 13 Bandung on the topic of Stoichiometry

NASA Astrophysics Data System (ADS)

Hayat, A. Z.; Wahyu, W.; Kurnia

2018-05-01

This study aims to find out the improvement of cognitive ability of students on the implementation of cooperative learning model of peer-tutoring by using problem-solving approach. The research method used is mix method of Sequential Explanatory strategy and pretest post-test non-equivalent control group design. The participants involved in this study were 68 grade 10 students of Vocational High School in Bandung that consisted of 34 samples of experimental class and 34 samples of control class. The instruments used include written test and questionnaires. The improvement of cognitive ability of students was calculated using the N- gain formula. Differences of two average scores were calculated using t-test at significant level of α = 0.05. The result of study shows that the improvement of cognitive ability in experimental class was significantly different compared to the improvement in the control class at significant level of α = 0.05. The improvement of cognitive ability in experimental class is higher than in control class.

The Learning of Compost Practice in University

NASA Astrophysics Data System (ADS)

Agustina, T. W.; Rustaman, N. Y.; Riandi; Purwianingsih, W.

2017-09-01

The compost as one of the topics of the Urban Farming Movement in Bandung city, Indonesia. The preliminary study aims to obtain a description of the performance capabilities and compost products made by students with STREAM (Science-Technology-Religion-Art-Mathematics) approach. The method was explanatory sequential mixed method. The study was conducted on one class of Biology Education students at the one of the universities in Bandung, Indonesia. The sample was chosen purposively with the number of students as many as 44 people. The instruments were making Student Worksheets, Observation Sheets of Performance and Product Assessment, Rubric of Performance and Product, and Field Notes. The indicators of performance assessment rubrics include Stirring of Compost Materials and Composting Technology in accordance with the design. The product assessment rubric are a Good Composting Criteria and Compost Packaging. The result of can be stated most students have good performance. However, the ability to design of compost technology, compost products and the ability to pack compost are still lacking. The implication of study is students of Biology Education require habituation in the ability of designing technology.

Sequential Probability Ratio Testing with Power Projective Base Method Improves Decision-Making for BCI

PubMed Central

Liu, Rong

2017-01-01

Obtaining a fast and reliable decision is an important issue in brain-computer interfaces (BCI), particularly in practical real-time applications such as wheelchair or neuroprosthetic control. In this study, the EEG signals were firstly analyzed with a power projective base method. Then we were applied a decision-making model, the sequential probability ratio testing (SPRT), for single-trial classification of motor imagery movement events. The unique strength of this proposed classification method lies in its accumulative process, which increases the discriminative power as more and more evidence is observed over time. The properties of the method were illustrated on thirteen subjects' recordings from three datasets. Results showed that our proposed power projective method outperformed two benchmark methods for every subject. Moreover, with sequential classifier, the accuracies across subjects were significantly higher than that with nonsequential ones. The average maximum accuracy of the SPRT method was 84.1%, as compared with 82.3% accuracy for the sequential Bayesian (SB) method. The proposed SPRT method provides an explicit relationship between stopping time, thresholds, and error, which is important for balancing the time-accuracy trade-off. These results suggest SPRT would be useful in speeding up decision-making while trading off errors in BCI. PMID:29348781

Cost-effectiveness of simultaneous versus sequential surgery in head and neck reconstruction.

PubMed

Wong, Kevin K; Enepekides, Danny J; Higgins, Kevin M

2011-02-01

To determine whether simultaneous (ablation and reconstruction overlaps by two teams) head and neck reconstruction is cost effective compared to sequentially (ablation followed by reconstruction) performed surgery. Case-controlled study. Tertiary care hospital. Oncology patients undergoing free flap reconstruction of the head and neck. A match paired comparison study was performed with a retrospective chart review examining the total time of surgery for sequential and simultaneous surgery. Nine patients were selected for both the sequential and simultaneous groups. Sequential head and neck reconstruction patients were pair matched with patients who had undergone similar oncologic ablative or reconstructive procedures performed in a simultaneous fashion. A detailed cost analysis using the microcosting method was then undertaken looking at the direct costs of the surgeons, anesthesiologist, operating room, and nursing. On average, simultaneous surgery required 3 hours 15 minutes less operating time, leading to a cost savings of approximately $1200/case when compared to sequential surgery. This represents approximately a 15% reduction in the cost of the entire operation. Simultaneous head and neck reconstruction is more cost effective when compared to sequential surgery.

Therapeutic effect for liver-metastasized tumor by sequential intravenous injection of anionic polymer and cationic lipoplex of siRNA.

PubMed

Hattori, Yoshiyuki; Arai, Shohei; Kikuchi, Takuto; Ozaki, Kei-Ichi; Kawano, Kumi; Yonemochi, Etsuo

2016-04-01

Previously, we developed a novel siRNA transfer method to the liver by sequential intravenous injection of anionic polymer and cationic liposome/siRNA complex (cationic lipoplex). In this study, we investigated whether siRNA delivered by this sequential injection could significantly suppress mRNA expression of the targeted gene in liver metastasis and inhibit tumor growth. When cationic lipoplex was intravenously injected into mice bearing liver metastasis of human breast tumor MCF-7 at 1 min after intravenous injection of chondroitin sulfate C (CS) or poly-l-glutamic acid (PGA), siRNA was accumulated in tumor-metastasized liver. In terms of a gene silencing effect, sequential injections of CS or PGA plus cationic lipoplex of luciferase siRNA could reduce luciferase activity in liver MCF-7-Luc metastasis. Regarding the side effects, sequential injections of CS plus cationic lipoplex did not exhibit hepatic damage or induction of inflammatory cytokines in serum after repeated injections, but sequential injections of PGA plus cationic lipoplex did. Finally, sequential injections of CS plus cationic lipoplex of protein kinase N3 siRNA could suppress tumor growth in the mice bearing liver metastasis. From these findings, sequential injection of CS and cationic lipoplex of siRNA might be a novel systemic method of delivering siRNA to liver metastasis.

Production and sequential decay of charmed hyperons

NASA Astrophysics Data System (ADS)

Fäldt, Göran

2018-03-01

We investigate production and decay of the Λc+ hyperon. The production considered is through the e+e- annihilation channel, e+e-→Λc+Λ¯c - , with summation over the Λ¯c- antihyperon spin directions. It is in this situation that the Λc+ decay chain is identified. Two kinds of sequential decays are studied. The first one is the doubly weak decay B1→B2M2 , followed by B2→B3M3. The other one is the mixed weak-electromagnetic decay B1→B2M2, followed by B2→B3γ . In both schemes B denotes baryons and M mesons. We should also mention that the initial state of the Λc+ hyperon is polarized.

Proceedings of the Conference on the Design of Experiments in Army Research, Development and Testing (29th)

DTIC Science & Technology

1984-06-01

SEQUENTIAL TESTING (Bldg. A, Room C) 1300-1330 ’ 1330-1415 1415-1445 1445-1515 BREAK 1515-1545 A TRUNCATED SEQUENTIAL PROBABILITY RATIO TEST J...suicide optical data operational testing reliability random numbers bootstrap methods missing data sequential testing fire support complex computer model carcinogenesis studies EUITION Of 1 NOV 68 I% OBSOLETE a ...contributed papers can be ascertained from the titles of the

Production of DagA and ethanol by sequential utilization of sugars in a mixed-sugar medium simulating microalgal hydrolysate.

PubMed

Park, Juyi; Hong, Soon-Kwang; Chang, Yong Keun

2015-09-01

A novel two-step fermentation process using a mixed-sugar medium mimicking microalgal hydrolysate has been proposed to avoid glucose repression and thus to maximize substrate utilization efficiency. When DagA, a β-agarase was produced in one step in the mixed-sugar medium by using a recombinant Streptomyces lividans, glucose was found to have negative effects on the consumption of the other sugars and DagA biosynthesis causing low substrate utilization efficiency and low DagA productivity. To overcome such difficulties, a new strategy of sequential substrate utilization was developed. In the first step, glucose was consumed by Saccharomyces cerevisiae together with galactose and mannose producing ethanol, after which DagA was produced from the remaining sugars of xylose, rhamnose and ribose. Fucose was not consumed. By adopting this two-step process, the overall substrate utilization efficiency was increased approximately 3-fold with a nearly 2-fold improvement of DagA production, let alone the additional benefit of ethanol production. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sequential Aldol Condensation – Transition Metal-Catalyzed Addition Reactions of Aldehydes, Methyl Ketones and Arylboronic Acids

PubMed Central

Liao, Yuan-Xi; Xing, Chun-Hui; Israel, Matthew; Hu, Qiao-Sheng

2011-01-01

Sequential aldol condensation of aldehydes with methyl ketones followed by transition metal-catalyzed addition reactions of arylboronic acids to form β-substituted ketones is described. By using the 1,1′-spirobiindane-7,7′-diol (SPINOL)-based phosphite, an asymmetric version of this type of sequential reaction, with up to 92% ee, was also realized. Our study provided an efficient method to access β-substituted ketones and might lead to the development of other sequential/tandem reactions with transition metal-catalyzed addition reactions as the key step. PMID:21417359

Sequential aldol condensation-transition metal-catalyzed addition reactions of aldehydes, methyl ketones, and arylboronic acids.

PubMed

Liao, Yuan-Xi; Xing, Chun-Hui; Israel, Matthew; Hu, Qiao-Sheng

2011-04-15

Sequential aldol condensation of aldehydes with methyl ketones followed by transition metal-catalyzed addition reactions of arylboronic acids to form β-substituted ketones is described. By using the 1,1'-spirobiindane-7,7'-diol (SPINOL)-based phosphite, an asymmetric version of this type of sequential reaction, with up to 92% ee, was also realized. Our study provided an efficient method to access β-substituted ketones and might lead to the development of other sequential/tandem reactions with transition metal-catalyzed addition reactions as the key step. © 2011 American Chemical Society

Exercise therapy in oncology rehabilitation in Australia: A mixed-methods study.

PubMed

Dennett, Amy M; Peiris, Casey L; Shields, Nora; Morgan, Delwyn; Taylor, Nicholas F

2017-10-01

Oncology rehabilitation improves outcomes for cancer survivors but little is known about program availability in Australia. The aims of this study were: to describe oncology rehabilitation programs in Australia: determine whether the exercise component of programs is consistent with guidelines: and to explore barriers and facilitators to program implementation. A sequential, explanatory mixed-methods study was completed in two phases: (1) a survey of Australian oncology rehabilitation programs; and (2) purposively sampled follow-up semistructured interviews with senior clinicians working in oncology rehabilitation who were involved with exercise prescription. Hospitals and/or cancer centers from 42 public hospital health networks (representing 163 hospitals) and 39 private hospitals were contacted to identify 31 oncology rehabilitation programs. All 31 surveys were returned (100% response rate). Programs were typically multidisciplinary, ran twice weekly, provided education and exercise and included self-management strategies. Exercise prescription and progression was patient centered and included a combination of resistance and aerobic training supplemented by balance, pelvic floor, and core stability exercises. Challenges to implementation included a lack of awareness of programs in the community and organizational barriers such as funding. Strong links with oncologists facilitated program referrals. Despite evidence to support oncology rehabilitation, there are few programs in Australia and there are challenges that limit it becoming part of standard practice. Programs that exist are multidisciplinary with a focus on exercise with the majority of programs following a cardiac rehabilitation model of care. © 2016 John Wiley & Sons Australia, Ltd.

ARCH: Adaptive recurrent-convolutional hybrid networks for long-term action recognition

PubMed Central

Xin, Miao; Zhang, Hong; Wang, Helong; Sun, Mingui; Yuan, Ding

2017-01-01

Recognition of human actions from digital video is a challenging task due to complex interfering factors in uncontrolled realistic environments. In this paper, we propose a learning framework using static, dynamic and sequential mixed features to solve three fundamental problems: spatial domain variation, temporal domain polytrope, and intra- and inter-class diversities. Utilizing a cognitive-based data reduction method and a hybrid “network upon networks” architecture, we extract human action representations which are robust against spatial and temporal interferences and adaptive to variations in both action speed and duration. We evaluated our method on the UCF101 and other three challenging datasets. Our results demonstrated a superior performance of the proposed algorithm in human action recognition. PMID:29290647

Dragon boat racing and health-related quality of life of breast cancer survivors: a mixed methods evaluation.

PubMed

Ray, Heather A; Verhoef, Marja J

2013-08-05

Breast cancer survivors who participate in physical activity (PA) are reported to experience improved health-related quality of life (HRQOL). However, the quantitative research exploring the relationship between the team-based activity of dragon boat racing and the HRQOL of breast cancer survivors is limited. Given the rising number of breast cancer survivors, and their growing attraction to dragon boating, further exploration of the influence of this activity on HRQOL is warranted. This study is designed to: 1) quantitatively assess whether and how breast cancer survivors' participation in a season of dragon boat racing is related to HRQOL and 2) qualitatively explore the survivors' lived experience of dragon boating and how and why this experience is perceived to influence HRQOL. A mixed methods sequential explanatory design was used with the purpose of complementing quantitative findings with qualitative data. Quantitative data measuring HRQOL were collected at baseline and post-season (N=100); semi-structured qualitative interviews were used to elicit a personal account of the dragon boat experience (N=15). Statistically significant improvements were shown for HRQOL, physical, functional, emotional and spiritual well-being, breast cancer-specific concerns and cancer-related fatigue. A trend towards significance was shown for social/family well-being. Qualitative data elaborated on the quantitative findings, greatly enhancing the understanding of how and why dragon boat racing influences HRQOL. The use of a mixed methods design effectively captured the complex yet positive influence of dragon boating on survivor HRQOL. These findings contribute to a growing body of literature supporting the value of dragon boat racing as a viable PA intervention for enhancing survivor HRQOL.

Molten salt electrodeposition of high temperature superconductors. Final report, 7 September 1990-30 November 1992

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

Tench, D.M.; Kendig, M.W.; Jeanjaquet, S.

1993-06-01

The overall objective of this project was to develop a process for direct electrodeposition of Y-Ba-Cu superconducting oxides from a molten salt at relatively low temperatures (300-550 deg C). An important finding was that cathodic deposition of metallic oxides, rather than free metals, generally occurs from nitrate melts, apparently via reduction of metal nitrato complexes. Oxide deposition was confirmed for Cu as CuO, Y as Y2O3, and Co as Co3O4, and apparently also occurs for Ba. Deposition of mixed Ba-Y-Cu oxides was demonstrated on both Cu and Pt substrates. Data were compiled that provide a good basis for designing schemesmore » for deposition of various mixed oxides from nitrate melts. A sequential anodic injection method was conceived for depositing ultrathin mixed oxide layers, which can be viewed as an analog of molecular beam epitaxy. Results obtained with this approach were encouraging but were inconclusive because of contamination with Gd from the Y injection anode. Based on the results of this program and literature studies, cathodic metal oxide deposition from nitrate melts is a general phenomenon that could ultimately prove to be a practical means of preparing a variety of single and mixed anhydrous metal oxide films. It is recommended that future work focus initially on deposition of perovskite materials, which are of considerable practical interest and involve only two metallic components so that the required deposition schemes are inherently simpler.« less

Sensitivity Analysis in Sequential Decision Models.

PubMed

Chen, Qiushi; Ayer, Turgay; Chhatwal, Jagpreet

2017-02-01

Sequential decision problems are frequently encountered in medical decision making, which are commonly solved using Markov decision processes (MDPs). Modeling guidelines recommend conducting sensitivity analyses in decision-analytic models to assess the robustness of the model results against the uncertainty in model parameters. However, standard methods of conducting sensitivity analyses cannot be directly applied to sequential decision problems because this would require evaluating all possible decision sequences, typically in the order of trillions, which is not practically feasible. As a result, most MDP-based modeling studies do not examine confidence in their recommended policies. In this study, we provide an approach to estimate uncertainty and confidence in the results of sequential decision models. First, we provide a probabilistic univariate method to identify the most sensitive parameters in MDPs. Second, we present a probabilistic multivariate approach to estimate the overall confidence in the recommended optimal policy considering joint uncertainty in the model parameters. We provide a graphical representation, which we call a policy acceptability curve, to summarize the confidence in the optimal policy by incorporating stakeholders' willingness to accept the base case policy. For a cost-effectiveness analysis, we provide an approach to construct a cost-effectiveness acceptability frontier, which shows the most cost-effective policy as well as the confidence in that for a given willingness to pay threshold. We demonstrate our approach using a simple MDP case study. We developed a method to conduct sensitivity analysis in sequential decision models, which could increase the credibility of these models among stakeholders.

Group sequential designs for stepped-wedge cluster randomised trials

PubMed Central

Grayling, Michael J; Wason, James MS; Mander, Adrian P

2017-01-01

Background/Aims: The stepped-wedge cluster randomised trial design has received substantial attention in recent years. Although various extensions to the original design have been proposed, no guidance is available on the design of stepped-wedge cluster randomised trials with interim analyses. In an individually randomised trial setting, group sequential methods can provide notable efficiency gains and ethical benefits. We address this by discussing how established group sequential methodology can be adapted for stepped-wedge designs. Methods: Utilising the error spending approach to group sequential trial design, we detail the assumptions required for the determination of stepped-wedge cluster randomised trials with interim analyses. We consider early stopping for efficacy, futility, or efficacy and futility. We describe first how this can be done for any specified linear mixed model for data analysis. We then focus on one particular commonly utilised model and, using a recently completed stepped-wedge cluster randomised trial, compare the performance of several designs with interim analyses to the classical stepped-wedge design. Finally, the performance of a quantile substitution procedure for dealing with the case of unknown variance is explored. Results: We demonstrate that the incorporation of early stopping in stepped-wedge cluster randomised trial designs could reduce the expected sample size under the null and alternative hypotheses by up to 31% and 22%, respectively, with no cost to the trial’s type-I and type-II error rates. The use of restricted error maximum likelihood estimation was found to be more important than quantile substitution for controlling the type-I error rate. Conclusion: The addition of interim analyses into stepped-wedge cluster randomised trials could help guard against time-consuming trials conducted on poor performing treatments and also help expedite the implementation of efficacious treatments. In future, trialists should consider incorporating early stopping of some kind into stepped-wedge cluster randomised trials according to the needs of the particular trial. PMID:28653550

Developing a Self-Report-Based Sequential Analysis Method for Educational Technology Systems: A Process-Based Usability Evaluation

ERIC Educational Resources Information Center

Lin, Yi-Chun; Hsieh, Ya-Hui; Hou, Huei-Tse

2015-01-01

The development of a usability evaluation method for educational systems or applications, called the self-report-based sequential analysis, is described herein. The method aims to extend the current practice by proposing self-report-based sequential analysis as a new usability method, which integrates the advantages of self-report in survey…

Sequential and simultaneous SLAR block adjustment. [spline function analysis for mapping

NASA Technical Reports Server (NTRS)

Leberl, F.

1975-01-01

Two sequential methods of planimetric SLAR (Side Looking Airborne Radar) block adjustment, with and without splines, and three simultaneous methods based on the principles of least squares are evaluated. A limited experiment with simulated SLAR images indicates that sequential block formation with splines followed by external interpolative adjustment is superior to the simultaneous methods such as planimetric block adjustment with similarity transformations. The use of the sequential block formation is recommended, since it represents an inexpensive tool for satisfactory point determination from SLAR images.

Classification and Sequential Pattern Analysis for Improving Managerial Efficiency and Providing Better Medical Service in Public Healthcare Centers

PubMed Central

Chung, Sukhoon; Rhee, Hyunsill; Suh, Yongmoo

2010-01-01

Objectives This study sought to find answers to the following questions: 1) Can we predict whether a patient will revisit a healthcare center? 2) Can we anticipate diseases of patients who revisit the center? Methods For the first question, we applied 5 classification algorithms (decision tree, artificial neural network, logistic regression, Bayesian networks, and Naïve Bayes) and the stacking-bagging method for building classification models. To solve the second question, we performed sequential pattern analysis. Results We determined: 1) In general, the most influential variables which impact whether a patient of a public healthcare center will revisit it or not are personal burden, insurance bill, period of prescription, age, systolic pressure, name of disease, and postal code. 2) The best plain classification model is dependent on the dataset. 3) Based on average of classification accuracy, the proposed stacking-bagging method outperformed all traditional classification models and our sequential pattern analysis revealed 16 sequential patterns. Conclusions Classification models and sequential patterns can help public healthcare centers plan and implement healthcare service programs and businesses that are more appropriate to local residents, encouraging them to revisit public health centers. PMID:21818426

A parallel metaheuristic for large mixed-integer dynamic optimization problems, with applications in computational biology

PubMed Central

Henriques, David; González, Patricia; Doallo, Ramón; Saez-Rodriguez, Julio; Banga, Julio R.

2017-01-01

Background We consider a general class of global optimization problems dealing with nonlinear dynamic models. Although this class is relevant to many areas of science and engineering, here we are interested in applying this framework to the reverse engineering problem in computational systems biology, which yields very large mixed-integer dynamic optimization (MIDO) problems. In particular, we consider the framework of logic-based ordinary differential equations (ODEs). Methods We present saCeSS2, a parallel method for the solution of this class of problems. This method is based on an parallel cooperative scatter search metaheuristic, with new mechanisms of self-adaptation and specific extensions to handle large mixed-integer problems. We have paid special attention to the avoidance of convergence stagnation using adaptive cooperation strategies tailored to this class of problems. Results We illustrate its performance with a set of three very challenging case studies from the domain of dynamic modelling of cell signaling. The simpler case study considers a synthetic signaling pathway and has 84 continuous and 34 binary decision variables. A second case study considers the dynamic modeling of signaling in liver cancer using high-throughput data, and has 135 continuous and 109 binaries decision variables. The third case study is an extremely difficult problem related with breast cancer, involving 690 continuous and 138 binary decision variables. We report computational results obtained in different infrastructures, including a local cluster, a large supercomputer and a public cloud platform. Interestingly, the results show how the cooperation of individual parallel searches modifies the systemic properties of the sequential algorithm, achieving superlinear speedups compared to an individual search (e.g. speedups of 15 with 10 cores), and significantly improving (above a 60%) the performance with respect to a non-cooperative parallel scheme. The scalability of the method is also good (tests were performed using up to 300 cores). Conclusions These results demonstrate that saCeSS2 can be used to successfully reverse engineer large dynamic models of complex biological pathways. Further, these results open up new possibilities for other MIDO-based large-scale applications in the life sciences such as metabolic engineering, synthetic biology, drug scheduling. PMID:28813442

Primary care physicians' perceived barriers and facilitators to conservative care for older adults with chronic kidney disease: design of a mixed methods study.

PubMed

Tam-Tham, Helen; Hemmelgarn, Brenda; Campbell, David; Thomas, Chandra; Quinn, Robert; Fruetel, Karen; King-Shier, Kathryn

2016-01-01

Guideline committees have identified the need for research to inform the provision of conservative care for older adults with stage 5 chronic kidney disease (CKD) who have a high burden of comorbidity or functional impairment. We will use both qualitative and quantitative methodologies to provide a comprehensive understanding of barriers and facilitators to care for these patients in primary care. Our objectives are to (1) interview primary care physicians to determine their perspectives of conservative care for older adults with stage 5 CKD and (2) survey primary care physicians to determine the prevalence of key barriers and facilitators to provision of conservative care for older adults with stage 5 CKD. A sequential exploratory mixed methods design was adopted for this study. The first phase of the study will involve fundamental qualitative description and the second phase will be a cross-sectional population-based survey. The research is conducted in Alberta, Canada. The participants are primary care physicians with experience in providing care for older adults with stage 5 CKD not planning on initiating dialysis. The first objective will be achieved by undertaking interviews with primary care physicians from southern Alberta. Participants will be selected purposively to include physicians with a range of characteristics (e.g., age, gender, and location of clinical practice). Interviews will be recorded, transcribed verbatim, and analyzed using conventional content analysis to generate themes. The second objective will be achieved by undertaking a population-based survey of primary care physicians in Alberta. The questionnaire will be developed based on the findings from the qualitative interviews and pilot tested for face and content validity. Physicians will be provided multiple options to complete the questionnaire including mail, fax, and online methods. Descriptive statistics and associations between demographic factors and barriers and facilitators to care will be analyzed using regression models. A potential limitation of this mixed methods study is its cross-sectional nature. This work will inform development of clinical resources and tools for care of older adults with stage 5 CKD, to address barriers and enable facilitators to community-based conservative care.

The Role of E-Mail Communications in Determining Response Rates and Mode of Participation in a Mixed-Mode Design

ERIC Educational Resources Information Center

Cernat, Alexandru; Lynn, Peter

2018-01-01

This article is concerned with the extent to which the propensity to participate in a web face-to-face sequential mixed-mode survey is influenced by the ability to communicate with sample members by e-mail in addition to mail. Researchers may be able to collect e-mail addresses for sample members and to use them subsequently to send survey…

PC_Eyewitness and the sequential superiority effect: computer-based lineup administration.

PubMed

MacLin, Otto H; Zimmerman, Laura A; Malpass, Roy S

2005-06-01

Computer technology has become an increasingly important tool for conducting eyewitness identifications. In the area of lineup identifications, computerized administration offers several advantages for researchers and law enforcement. PC_Eyewitness is designed specifically to administer lineups. To assess this new lineup technology, two studies were conducted in order to replicate the results of previous studies comparing simultaneous and sequential lineups. One hundred twenty university students participated in each experiment. Experiment 1 used traditional paper-and-pencil lineup administration methods to compare simultaneous to sequential lineups. Experiment 2 used PC_Eyewitness to administer simultaneous and sequential lineups. The results of these studies were compared to the meta-analytic results reported by N. Steblay, J. Dysart, S. Fulero, and R. C. L. Lindsay (2001). No differences were found between paper-and-pencil and PC_Eyewitness lineup administration methods. The core findings of the N. Steblay et al. (2001) meta-analysis were replicated by both administration procedures. These results show that computerized lineup administration using PC_Eyewitness is an effective means for gathering eyewitness identification data.

Mechanical System Reliability and Cost Integration Using a Sequential Linear Approximation Method

NASA Technical Reports Server (NTRS)

Kowal, Michael T.

1997-01-01

The development of new products is dependent on product designs that incorporate high levels of reliability along with a design that meets predetermined levels of system cost. Additional constraints on the product include explicit and implicit performance requirements. Existing reliability and cost prediction methods result in no direct linkage between variables affecting these two dominant product attributes. A methodology to integrate reliability and cost estimates using a sequential linear approximation method is proposed. The sequential linear approximation method utilizes probability of failure sensitivities determined from probabilistic reliability methods as well a manufacturing cost sensitivities. The application of the sequential linear approximation method to a mechanical system is demonstrated.

Computer-Based Radiographic Quantification of Joint Space Narrowing Progression Using Sequential Hand Radiographs: Validation Study in Rheumatoid Arthritis Patients from Multiple Institutions.

PubMed

Ichikawa, Shota; Kamishima, Tamotsu; Sutherland, Kenneth; Fukae, Jun; Katayama, Kou; Aoki, Yuko; Okubo, Takanobu; Okino, Taichi; Kaneda, Takahiko; Takagi, Satoshi; Tanimura, Kazuhide

2017-10-01

We have developed a refined computer-based method to detect joint space narrowing (JSN) progression with the joint space narrowing progression index (JSNPI) by superimposing sequential hand radiographs. The purpose of this study is to assess the validity of a computer-based method using images obtained from multiple institutions in rheumatoid arthritis (RA) patients. Sequential hand radiographs of 42 patients (37 females and 5 males) with RA from two institutions were analyzed by a computer-based method and visual scoring systems as a standard of reference. The JSNPI above the smallest detectable difference (SDD) defined JSN progression on the joint level. The sensitivity and specificity of the computer-based method for JSN progression was calculated using the SDD and a receiver operating characteristic (ROC) curve. Out of 314 metacarpophalangeal joints, 34 joints progressed based on the SDD, while 11 joints widened. Twenty-one joints progressed in the computer-based method, 11 joints in the scoring systems, and 13 joints in both methods. Based on the SDD, we found lower sensitivity and higher specificity with 54.2 and 92.8%, respectively. At the most discriminant cutoff point according to the ROC curve, the sensitivity and specificity was 70.8 and 81.7%, respectively. The proposed computer-based method provides quantitative measurement of JSN progression using sequential hand radiographs and may be a useful tool in follow-up assessment of joint damage in RA patients.

A Comparison of Two Instructional Methods for Teaching Logo to Learning Disabled and Nonlearning Disabled Children.

ERIC Educational Resources Information Center

Mathinos, Debra A.; Leonard, Ann Scheier

The study examines the use of LOGO, a computer language, with 19 learning disabled (LD) and 19 non-LD students in grades 4-6. Ss were randomly assigned to one of two instructional groups: sequential or whole-task, each with 10 LD and 10 non-LD students. The sequential method features a carefully ordered plan for teaching LOGO commands; the…

Men's behavior surrounding use of contraceptives in Guinea.

PubMed

Baldé, Mamadou Diouldé; Diallo, Boubacar Alpha; Compaoré, Rachidatou; Bah, Abdoul Karim; Ali, Moazzam; Kabra, Rita; Kouanda, Seni

2016-11-01

To analyze the sociocultural determinants that influence the attitude and practices of men toward contraceptive use in Guinea. A sequential, mixed methods, qualitative and quantitative study was carried out in two regions of Guinea with a low rate of contraceptive prevalence, and in the capital city of Conakry. A total of 1170 people (men and women) were interviewed. Findings showed a positive perception of family planning overall, but reluctance to use modern contraception. The reasons for non-use of contraceptive methods were primarily the hope of having many children and religious prohibition associated with customs. Making decisions on contraceptive use within a couple represents a major cause of misunderstanding between spouses. Communication within a couple on the use of contraception is quickly declined by men. The findings demonstrate the need to develop communication strategies within a couple to improve the use of contraceptives. Copyright © 2016 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

Social Support of Patients with Type 2 Diabetes in Marginalized Contexts in Mexico and Its Relation to Compliance with Treatment: A Sociocultural Approach

PubMed Central

Juárez-Ramírez, Clara; Théodore, Florence L.; Villalobos, Aremis; Jiménez-Corona, Aida; Lerin, Sergio; Nigenda, Gustavo; Lewis, Sarah

2015-01-01

Objective This study aimed to describe the ways social support works in the daily life of patients with type 2 diabetes living in conditions of social and economic marginality, in order to understand how that support relates to treatment compliance. Methods Sequential mixed methods research was used. The sample of patients was obtained from primary health care units and selected considering regional representativeness, and levels of morbidity and mortality for type 2 diabetes. Results Results point to the nuclear family as the main source of support. Regardless of the area of residence, four main dimensions of support were identified: economic support, help with treatment compliance, emotional support, and material aid. Conclusions We conclude that the support network assists the patient in different ways and helps cope with the disease, but in conditions of social and economic marginality, does not guarantee the quality of attention nor enable the self-management of treatment. PMID:26545122

Profiles of eight working mothers who practiced exclusive breastfeeding in Depok, Indonesia.

PubMed

Februhartanty, Judhiastuty; Wibowo, Yulianti; Fahmida, Umi; Roshita, Airin

2012-02-01

Exclusive breastfeeding practice is generally low because of multifaceted factors internally within mothers themselves and also the surroundings. In addition, studies have consistently found that maternal employment outside the home is related to shorter duration of exclusive breastfeeding. With all these challenges, it is interesting that there are some mothers who manage to exclusively breastfeed their infants. Therefore, this report aims at exploring the characteristics of working mothers who are able to practice exclusive breastfeeding. The original study population was non-working and working mothers who have infants around 1 to 6 months old. The study design is an observational study with a mixed methods approach using a quantitative study (survey) and qualitative methods (in-depth interview) in sequential order. In addition, in-depth interviews with family members, midwives, supervisors at work, and community health workers were also included to accomplish a holistic picture of the situation. The study concludes that self-efficacy and confidence of the breastfeeding mothers characterize the practice of exclusive breastfeeding. Good knowledge that was acquired way before the mothers got pregnant suggests a predisposing factor to the current state of confidence. Home support from the father enhances the decision to sustain breastfeeding.

C-learning: A new classification framework to estimate optimal dynamic treatment regimes.

PubMed

Zhang, Baqun; Zhang, Min

2017-12-11

A dynamic treatment regime is a sequence of decision rules, each corresponding to a decision point, that determine that next treatment based on each individual's own available characteristics and treatment history up to that point. We show that identifying the optimal dynamic treatment regime can be recast as a sequential optimization problem and propose a direct sequential optimization method to estimate the optimal treatment regimes. In particular, at each decision point, the optimization is equivalent to sequentially minimizing a weighted expected misclassification error. Based on this classification perspective, we propose a powerful and flexible C-learning algorithm to learn the optimal dynamic treatment regimes backward sequentially from the last stage until the first stage. C-learning is a direct optimization method that directly targets optimizing decision rules by exploiting powerful optimization/classification techniques and it allows incorporation of patient's characteristics and treatment history to improve performance, hence enjoying advantages of both the traditional outcome regression-based methods (Q- and A-learning) and the more recent direct optimization methods. The superior performance and flexibility of the proposed methods are illustrated through extensive simulation studies. © 2017, The International Biometric Society.

Variations in the Summer Phytoplankton Community Structure in Atlantic sub-Arctic and Arctic Waters

NASA Astrophysics Data System (ADS)

Small, A.; Hughes, C.; Bouman, H. A.

2016-02-01

Shifts in phytoplankton community structure serve not only as indicators of environmental change but also have implications for food-web interactions and biogeochemical cycles. The community structure of marine phytoplankton in sub-Arctic and Arctic waters was examined using 159 samples collected in the summer of 2013 along a latitudinal gradient spanning from 61.1 to 83.1 degrees N along the east coast of Greenland. Accessory pigment concentrations were used to infer information about the phytoplankton taxa present using CHEMTAX (CHEMical TAXonomy), an iterative MATLAB subroutine. The main algal classes found within the study region were diatoms, dinoflagellates, haptophytes, chlorophytes, cryptophytes and prasinophytes. Diatoms were present at nearly all stations and depths and were large contributors to the total pigment biomass for both ice and open water stations. Deeper samples were mainly dominated by diatoms and haptophytes. Surface sample communities were characterised by mixed assemblages, including dinoflagellates and chlorophytes although diatoms and haptophytes still comprised a significant portion of the pigment biomass. The differences in community structure were investigated in relation to the environmental conditions through multivariate statistical analysis (cluster and principle component analyses) in order to understand the factors influencing the spatial distribution of the various algal classes. Diagnostic pigment indices were also used to calculate the concentration of Chl-a attributed to three size classes (picophytoplankton 0.2-2µm, nanophytoplankton 2-20µm and microphytoplankton >20µm). These data were compared to a similar dataset from the same cruise where size fractionated Chl-a was separated by sequential filtration and quantified by fluorometric analysis. Size-fractionated Chl-a as measured directly by sequential filtration suggested a primarily mixed community across the study region. In contrast pigment based analysis suggested a strong dominance of larger cells and also resulted in the complete absence of picoplankton in some samples. These results suggest that diagnostic pigment indices may not be an accurate method of determining size classes in this region.

Use of personalized Dynamic Treatment Regimes (DTRs) and Sequential Multiple Assignment Randomized Trials (SMARTs) in mental health studies

PubMed Central

Liu, Ying; ZENG, Donglin; WANG, Yuanjia

2014-01-01

Summary Dynamic treatment regimens (DTRs) are sequential decision rules tailored at each point where a clinical decision is made based on each patient’s time-varying characteristics and intermediate outcomes observed at earlier points in time. The complexity, patient heterogeneity, and chronicity of mental disorders call for learning optimal DTRs to dynamically adapt treatment to an individual’s response over time. The Sequential Multiple Assignment Randomized Trial (SMARTs) design allows for estimating causal effects of DTRs. Modern statistical tools have been developed to optimize DTRs based on personalized variables and intermediate outcomes using rich data collected from SMARTs; these statistical methods can also be used to recommend tailoring variables for designing future SMART studies. This paper introduces DTRs and SMARTs using two examples in mental health studies, discusses two machine learning methods for estimating optimal DTR from SMARTs data, and demonstrates the performance of the statistical methods using simulated data. PMID:25642116

Simultaneous biodegradation of three mononitrophenol isomers by a tailor-made microbial consortium immobilized in sequential batch reactors.

PubMed

Fu, H; Zhang, J-J; Xu, Y; Chao, H-J; Zhou, N-Y

2017-03-01

The ortho-nitrophenol (ONP)-utilizing Alcaligenes sp. strain NyZ215, meta-nitrophenol (MNP)-utilizing Cupriavidus necator JMP134 and para-nitrophenol (PNP)-utilizing Pseudomonas sp. strain WBC-3 were assembled as a consortium to degrade three nitrophenol isomers in sequential batch reactors. Pilot test was conducted in flasks to demonstrate that a mixture of three mononitrophenols at 0·5 mol l -1 each could be mineralized by this microbial consortium within 84 h. Interestingly, neither ONP nor MNP was degraded until PNP was almost consumed by strain WBC-3. By immobilizing this consortium into polyurethane cubes, all three mononitrophenols were continuously degraded in lab-scale sequential reactors for six batch cycles over 18 days. Total concentrations of ONP, MMP and PNP that were degraded were 2·8, 1·5 and 2·3 mol l -1 during this time course respectively. Quantitative real-time PCR analysis showed that each member in the microbial consortium was relatively stable during the entire degradation process. This study provides a novel approach to treat polluted water, particularly with a mixture of co-existing isomers. Nitroaromatic compounds are readily spread in the environment and pose great potential toxicity concerns. Here, we report the simultaneous degradation of three isomers of mononitrophenol in a single system by employing a consortium of three bacteria, both in flasks and lab-scale sequential batch reactors. The results demonstrate that simultaneous biodegradation of three mononitrophenol isomers can be achieved by a tailor-made microbial consortium immobilized in sequential batch reactors, providing a pilot study for a novel approach for the bioremediation of mixed pollutants, especially isomers present in wastewater. © 2016 The Society for Applied Microbiology.

A Longitudinal Study in Adults with Sequential Bilateral Cochlear Implants: Time Course for Individual Ear and Bilateral Performance

ERIC Educational Resources Information Center

Reeder, Ruth M.; Firszt, Jill B.; Holden, Laura K.; Strube, Michael J.

2014-01-01

Purpose: The purpose of this study was to examine the rate of progress in the 2nd implanted ear as it relates to the 1st implanted ear and to bilateral performance in adult sequential cochlear implant recipients. In addition, this study aimed to identify factors that contribute to patient outcomes. Method: The authors performed a prospective…

Sustainability of outdoor school ground smoking bans at secondary schools: a mixed-method study

PubMed Central

Rozema, A D; Mathijssen, J J P; Jansen, M W J; van Oers, J A M

2018-01-01

Abstract Background Although increasing numbers of countries are implementing outdoor school ground smoking bans at secondary schools, less attention is paid to the post-implementation period even though sustainability of a policy is essential for long-term effectiveness. Therefore, this study assesses the level of sustainability and examines perceived barriers/facilitators related to the sustainability of an outdoor school ground smoking ban at secondary schools. Methods A mixed-method design was used with a sequential explanatory approach. In phase I, 438 online surveys were conducted and in phase II, 15 semi-structured interviews were obtained from directors of relevant schools. ANOVA (phase I) and a thematic approach (phase II) were used to analyze data. Results Level of sustainability of an outdoor school ground smoking ban was high at the 48% Dutch schools with an outdoor smoking ban. Furthermore, school size was significantly associated with sustainability. The perceived barriers/facilitators fell into three categories: (i) smoking ban implementation factors (side-effects, enforcement, communication, guidelines and collaboration), (ii) school factors (physical environment, school culture, education type and school policy) and (iii) community environment factors (legislation and social environment). Conclusions Internationally, the spread of outdoor school ground smoking bans could be further promoted. Once implemented, the ban has become ‘normal’ practice and investments tend to endure. Moreover, involvement of all staff is important for sustainability as they function as role models, have an interrelationship with students, and share responsibility for enforcement. These findings are promising for the sustainability of future tobacco control initiatives to further protect against the morbidity/mortality associated with smoking. PMID:29016786

Fundamental Study on the Fabrication of Inverted Planar Perovskite Solar Cells Using Two-Step Sequential Substrate Vibration-Assisted Spray Coating (2S-SVASC).

PubMed

Zabihi, Fatemeh; Ahmadian-Yazdi, Mohammad-Reza; Eslamian, Morteza

2016-12-01

In this paper, a scalable and fast process is developed and employed for the fabrication of the perovskite light harvesting layer in inverted planar heterojunction solar cell (FTO/PEDOT:PSS/CH3NH3PbI3-x Cl x /PCBM/Al). Perovskite precursor solutions are sprayed onto an ultrasonically vibrating substrate in two sequential steps via a process herein termed as the two-step sequential substrate vibration-assisted spray coating (2S-SVASC). The gentle imposed ultrasonic vibration on the substrate promotes droplet spreading and coalescence, surface wetting, evaporation, mixing of reagents, and uniform growth of perovskite nanocrystals. The role of the substrate temperature, substrate vibration intensity, and the time interval between the two sequential sprays are studied on the roughness, coverage, and crystalline structure of perovskite thin films. We demonstrate that a combination of a long time interval between spraying of precursor solutions (15 min), a high substrate temperature (120 °C), and a mild substrate vibration power (5 W) results in a favorable morphology and surface quality. The characteristics and performance of prepared perovskite thin films made via the 2S-SVASC technique are compared with those of the co-sprayed perovskite thin films. The maximum power conversion efficiency of 5.08 % on a 0.3-cm(2) active area is obtained for the device made via the scalable 2S-SVASC technique.

Sequential Introduction of Cations Deriving Large-Grain Csx FA1-x PbI3 Thin Film for Planar Hybrid Solar Cells: Insight into Phase-Segregation and Thermal-Healing Behavior.

PubMed

Huang, Jiahao; Xu, Pan; Liu, Jian; You, Xiao-Zeng

2017-03-01

Composition engineering of perovskite materials has been demonstrated to be important for high-performance solar cells. Recently, the energy favorable hybridization of formamidinium (FA) and cesium (Cs) in three dimension lead halide perovskites has been attracting increasing attention due to its potential benefit on durability. Herein, we reported a simple and effective method to produce phase-pure CsxFA1-xPbI3 thin film via sequential introduction of cations, in which the FA cation was introduced by interdiffusion annealing in the presence of N-methylimidazole (NMI). NMI was employed as an additive to slow down the crystallization and thus drive the formation of CsxFA1-xPbI3 with micrometer grain size, which probably facilitate the charge dissociation and transportation in photovoltaic devices. More importantly, composition dependent phase-segregation has been revealed and investigated for the first time during the phase-pure mixed-cation perovskites CsxFA1-xPbI3. The present findings demonstrated that suppressing phase-segregation of mixed-cation perovskites by meticulous composition engineering is significant for further development of efficient photovoltaics. It also suggested that phase-pure Cs0.15FA0.85PbI3 may be a promising candidate with superior phase-durability, which performed an efficiency over 16% in planar perovskite solar cells. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The Science ELF: Assessing the enquiry levels framework as a heuristic for professional development

NASA Astrophysics Data System (ADS)

Wheeler, Lindsay B.; Bell, Randy L.; Whitworth, Brooke A.; Maeng, Jennifer L.

2015-01-01

This study utilized an explanatory sequential mixed methods approach to explore randomly assigned treatment and control participants' frequency of inquiry instruction in secondary science classrooms. Eleven treatment participants received professional development (PD) that emphasized a structured approach to inquiry instruction, while 10 control participants received no PD. Two representative treatment participants were interviewed and observed to provide an in-depth understanding of inquiry instruction and factors affecting implementation. Paired t-tests were used to analyze quantitative data from observation forms, and a constant comparative approach was used to analyze qualitative data from surveys, interviews, purposeful observations and artifacts. Results indicated that treatment participants implemented inquiry significantly more frequently than control participants (p < .01). Two treatment participants' instruction revealed that both used a similar structure of inquiry but employed different types of interactions and emphasized different scientific practices. These differences may be explained by the participants' understandings of and beliefs about inquiry and structuring inquiry. The present study has the potential to inform how methods of structuring inquiry instruction and teaching scientific practices are addressed in teacher preparation.

Cultural adaptation of a supportive care needs measure for Hispanic men cancer survivors.

PubMed

Martinez Tyson, Dinorah; Medina-Ramirez, Patricia; Vázquez-Otero, Coralia; Gwede, Clement K; Bobonis, Margarita; McMillan, Susan C

2018-01-01

Research with ethnic minority populations requires instrumentation that is cultural and linguistically relevant. The aim of this study was to translate and culturally adapt the Cancer Survivor Unmet Needs measure into Spanish. We describe the iterative, community-engaged consensus-building approaches used to adapt the instrument for Hispanic male cancer survivors. We used an exploratory sequential mixed method study design. Methods included translation and back-translation, focus groups with cancer survivors (n = 18) and providers (n = 5), use of cognitive interview techniques to evaluate the comprehension and acceptability of the adapted instrument with survivors (n = 12), ongoing input from the project's community advisory board, and preliminary psychometric analysis (n = 84). The process emphasized conceptual, content, semantic, and technical equivalence. Combining qualitative and quantitative approaches offered a rigorous, systematic, and contextual approach to translation alone and supports the cultural adaptation of this measure in a purposeful and relevant manner. Our findings highlight the importance of going beyond translation when adapting measures for cross-cultural populations and illustrate the importance of taking culture, literacy, and language into consideration.

Characteristics of sequential swallowing of liquids in young and elderly adults: an integrative review.

PubMed

Veiga, Helena Perrut; Bianchini, Esther Mandelbaum Gonçalves

2012-01-01

To perform an integrative review of studies on liquid sequential swallowing, by characterizing the methodology of the studies and the most important findings in young and elderly adults. Review of the literature written in English and Portuguese on PubMed, LILACS, SciELO and MEDLINE databases, within the past twenty years, available fully, using the following uniterms: sequential swallowing, swallowing, dysphagia, cup, straw, in various combinations. Research articles with a methodological approach on the characterization of liquid sequential swallowing by young and/or elderly adults, regardless of health condition, excluding studies involving only the esophageal phase. The following research indicators were applied: objectives, number and gender of participants; age group; amount of liquid offered; intake instruction; utensil used, methods and main findings. 18 studies met the established criteria. The articles were categorized according to the sample characterization and the methodology on volume intake, utensil used and types of exams. Most studies investigated only healthy individuals, with no swallowing complaints. Subjects were given different instructions as to the intake of all the volume: usual manner, continually, as rapidly as possible. The findings about the characterization of sequential swallowing were varied and described in accordance with the objectives of each study. It found great variability in the methodology employed to characterize the sequential swallowing. Some findings are not comparable, and sequential swallowing is not studied in most swallowing protocols, without consensus on the influence of the utensil.

An adaptive two-stage sequential design for sampling rare and clustered populations

USGS Publications Warehouse

Brown, J.A.; Salehi, M.M.; Moradi, M.; Bell, G.; Smith, D.R.

2008-01-01

How to design an efficient large-area survey continues to be an interesting question for ecologists. In sampling large areas, as is common in environmental studies, adaptive sampling can be efficient because it ensures survey effort is targeted to subareas of high interest. In two-stage sampling, higher density primary sample units are usually of more interest than lower density primary units when populations are rare and clustered. Two-stage sequential sampling has been suggested as a method for allocating second stage sample effort among primary units. Here, we suggest a modification: adaptive two-stage sequential sampling. In this method, the adaptive part of the allocation process means the design is more flexible in how much extra effort can be directed to higher-abundance primary units. We discuss how best to design an adaptive two-stage sequential sample. ?? 2008 The Society of Population Ecology and Springer.

The effects of multiple infections on the expression and evolution of virulence in a Daphnia-endoparasite system.

PubMed

Ben-Ami, Frida; Mouton, Laurence; Ebert, Dieter

2008-07-01

Multiple infections of a host by different strains of the same microparasite are common in nature. Although numerous models have been developed in an attempt to predict the evolutionary effects of intrahost competition, tests of the assumptions of these models are rare and the outcome is diverse. In the present study we examined the outcome of mixed-isolate infections in individual hosts, using a single clone of the waterflea Daphnia magna and three isolates of its semelparous endoparasite Pasteuria ramosa. We exposed individual Daphnia to single- and mixed-isolate infection treatments, both simultaneously and sequentially. Virulence was assessed by monitoring host mortality and fecundity, and parasite spore production was used as a measure of parasite fitness. Consistent with most assumptions, in multiply infected hosts we found that the virulence of mixed infections resembled that of the more virulent competitor, both in simultaneous multiple infections and in sequential multiple infections in which the virulent isolate was first to infect. The more virulent competitor also produced the vast majority of transmission stages. Only when the less virulent isolate was first to infect, the intrahost contest resembled scramble competition, whereby both isolates suffered by producing fewer transmission stages. Surprisingly, mixed-isolate infections resulted in lower fecundity-costs for the hosts, suggesting that parasite competition comes with an advantage for the host relative to single infections. Finally, spore production correlated positively with time-to-host-death. Thus, early-killing of more competitive isolates produces less transmission stages than less virulent, inferior isolates. Our results are consistent with the idea that less virulent parasite lines may be replaced by more virulent strains under conditions with high rates of multiple infections.

Modeling Eye Gaze Patterns in Clinician-Patient Interaction with Lag Sequential Analysis

PubMed Central

Montague, E; Xu, J; Asan, O; Chen, P; Chewning, B; Barrett, B

2011-01-01

Objective The aim of this study was to examine whether lag-sequential analysis could be used to describe eye gaze orientation between clinicians and patients in the medical encounter. This topic is particularly important as new technologies are implemented into multi-user health care settings where trust is critical and nonverbal cues are integral to achieving trust. This analysis method could lead to design guidelines for technologies and more effective assessments of interventions. Background Nonverbal communication patterns are important aspects of clinician-patient interactions and may impact patient outcomes. Method Eye gaze behaviors of clinicians and patients in 110-videotaped medical encounters were analyzed using the lag-sequential method to identify significant behavior sequences. Lag-sequential analysis included both event-based lag and time-based lag. Results Results from event-based lag analysis showed that the patients’ gaze followed that of clinicians, while clinicians did not follow patients. Time-based sequential analysis showed that responses from the patient usually occurred within two seconds after the initial behavior of the clinician. Conclusion Our data suggest that the clinician’s gaze significantly affects the medical encounter but not the converse. Application Findings from this research have implications for the design of clinical work systems and modeling interactions. Similar research methods could be used to identify different behavior patterns in clinical settings (physical layout, technology, etc.) to facilitate and evaluate clinical work system designs. PMID:22046723

The effect of N-acetylcysteine on the incidence of contrast-induced kidney injury: A systematic review and trial sequential analysis.

PubMed

Wang, Nelson; Qian, Pierre; Kumar, Shejil; Yan, Tristan D; Phan, Kevin

2016-04-15

There have been a myriad of studies investigating the effectiveness of N-acetylcysteine (NAC) in the prevention of contrast induced nephropathy (CIN) in patients undergoing coronary angiography (CAG) with or without percutaneous coronary intervention (PCI). However the consensus is still out about the effectiveness of NAC pre-treatment due to vastly mixed results amongst the literature. The aim of this study was to conduct a meta-analysis and trial sequential analysis to determine the effects of pre-operative NAC in lowering the incidence of CIN in patients undergoing CAG and/or PCI. A systematic literature search was performed to include all randomized controlled trials (RCTs) comparing NAC versus control as pretreatment for CAG and/or PCI. A traditional meta-analysis and several subgroup analyses were conducted using traditional meta-analysis with relative risk (RR), trial sequential analysis, and meta-regression analysis. 43 RCTs met our inclusion criteria giving a total of 3277 patients in both control and treatment arms. There was a significant reduction in the risk of CIN in the NAC treated group compared to control (OR 0.666; 95% CI, 0.532-0.834; I2=40.11%; p=0.004). Trial sequential analysis, using a relative risk reduction threshold of 15%, indicates that the evidence is firm. The results of the present paper support the use of NAC in the prevention of CIN in patients undergoing CAG±PCI. Future studies should focus on the benefits of NAC amongst subgroups of high-risk patients. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Low-dose cerebral perfusion computed tomography image restoration via low-rank and total variation regularizations

PubMed Central

Niu, Shanzhou; Zhang, Shanli; Huang, Jing; Bian, Zhaoying; Chen, Wufan; Yu, Gaohang; Liang, Zhengrong; Ma, Jianhua

2016-01-01

Cerebral perfusion x-ray computed tomography (PCT) is an important functional imaging modality for evaluating cerebrovascular diseases and has been widely used in clinics over the past decades. However, due to the protocol of PCT imaging with repeated dynamic sequential scans, the associative radiation dose unavoidably increases as compared with that used in conventional CT examinations. Minimizing the radiation exposure in PCT examination is a major task in the CT field. In this paper, considering the rich similarity redundancy information among enhanced sequential PCT images, we propose a low-dose PCT image restoration model by incorporating the low-rank and sparse matrix characteristic of sequential PCT images. Specifically, the sequential PCT images were first stacked into a matrix (i.e., low-rank matrix), and then a non-convex spectral norm/regularization and a spatio-temporal total variation norm/regularization were then built on the low-rank matrix to describe the low rank and sparsity of the sequential PCT images, respectively. Subsequently, an improved split Bregman method was adopted to minimize the associative objective function with a reasonable convergence rate. Both qualitative and quantitative studies were conducted using a digital phantom and clinical cerebral PCT datasets to evaluate the present method. Experimental results show that the presented method can achieve images with several noticeable advantages over the existing methods in terms of noise reduction and universal quality index. More importantly, the present method can produce more accurate kinetic enhanced details and diagnostic hemodynamic parameter maps. PMID:27440948

Knowledge, understanding and experiences of peritonitis amongst patients, and their families, undertaking peritoneal dialysis: A mixed methods study protocol.

PubMed

Baillie, Jessica; Gill, Paul; Courtenay, Molly

2018-01-01

This article is a report of a study protocol designed to examine patients' and families' knowledge and experiences of peritoneal dialysis-associated peritonitis. Peritonitis is a considerable problem for people using peritoneal dialysis, leading to antibiotics, hospitalization and decreased quality of life. For some patients, peritonitis requires changing renal replacement therapy and can be fatal. Peritonitis is distressing and some patients are unfamiliar with the signs and symptoms. Patients with better knowledge of peritonitis and adherence to peritoneal dialysis procedures have lower rates of peritonitis. Little is known about patients' and families' knowledge and experience of peritoneal dialysis-associated peritonitis in the United Kingdom. Ethical approval was gained in March 2017. To meet the study aim, a two-phase sequential explanatory mixed methods study is proposed. Phase One: An author-developed questionnaire will be sent to patients using peritoneal dialysis at five sites in England and Wales. Patients will be asked to consider inviting a relative to participate. The questionnaire will assess peritonitis knowledge and experience. Data will be analysed statistically. Phase Two: Semi-structured interviews will be conducted with a purposive sample of Phase One participants (n = 30) to explore their experiences of peritonitis in further depth. The data will be analysed thematically using Wolcott's (1994) approach. Data from the two phases will be synthesized to identify patients' and families' peritonitis information needs, to ensure they are appropriately supported to prevent, monitor, identify and report peritonitis. © 2017 John Wiley & Sons Ltd.

Enhancing the performance of tungsten doped InZnO thin film transistors via sequential ambient annealing

NASA Astrophysics Data System (ADS)

Park, Hyun-Woo; Song, Aeran; Kwon, Sera; Choi, Dukhyun; Kim, Younghak; Jun, Byung-Hyuk; Kim, Han-Ki; Chung, Kwun-Bum

2018-03-01

This study suggests a sequential ambient annealing process as an excellent post-treatment method to enhance the device performance and stability of W (tungsten) doped InZnO thin film transistors (WIZO-TFTs). Sequential ambient annealing at 250 °C significantly enhanced the device performance and stability of WIZO-TFTs, compared with other post-treatment methods, such as air ambient annealing and vacuum ambient annealing at 250 °C. To understand the enhanced device performance and stability of WIZO-TFT with sequential ambient annealing, we investigate the correlations between device performance and stability and electronic structures, such as band alignment, a feature of the conduction band, and band edge states below the conduction band. The enhanced performance of WIZO-TFTs with sequential ambient annealing is related to the modification of the electronic structure. In addition, the dominant mechanism responsible for the enhanced device performance and stability of WIZO-TFTs is considered to be a change in the shallow-level and deep-level band edge states below the conduction band.

Developing an evidence-based methodological framework to systematically compare HTA coverage decisions: A mixed methods study.

PubMed

Nicod, Elena; Kanavos, Panos

2016-01-01

Health Technology Assessment (HTA) often results in different coverage recommendations across countries for a same medicine despite similar methodological approaches. This paper develops and pilots a methodological framework that systematically identifies the reasons for these differences using an exploratory sequential mixed methods research design. The study countries were England, Scotland, Sweden and France. The methodological framework was built around three stages of the HTA process: (a) evidence, (b) its interpretation, and (c) its influence on the final recommendation; and was applied to two orphan medicinal products. The criteria accounted for at each stage were qualitatively analyzed through thematic analysis. Piloting the framework for two medicines, eight trials, 43 clinical endpoints and seven economic models were coded 155 times. Eighteen different uncertainties about this evidence were coded 28 times, 56% of which pertained to evidence commonly appraised and 44% to evidence considered by only some agencies. The poor agreement in interpreting this evidence (κ=0.183) was partly explained by stakeholder input (ns=48 times), or by agency-specific risk (nu=28 uncertainties) and value preferences (noc=62 "other considerations"), derived through correspondence analysis. Accounting for variability at each stage of the process can be achieved by codifying its existence and quantifying its impact through the application of this framework. The transferability of this framework to other disease areas, medicines and countries is ensured by its iterative and flexible nature, and detailed description. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Cultural continuity, traditional Indigenous language, and diabetes in Alberta First Nations: a mixed methods study.

PubMed

Oster, Richard T; Grier, Angela; Lightning, Rick; Mayan, Maria J; Toth, Ellen L

2014-10-19

We used an exploratory sequential mixed methods approach to study the association between cultural continuity, self-determination, and diabetes prevalence in First Nations in Alberta, Canada. We conducted a qualitative description where we interviewed 10 Cree and Blackfoot leaders (members of Chief and Council) from across the province to understand cultural continuity, self-determination, and their relationship to health and diabetes, in the Alberta First Nations context. Based on the qualitative findings, we then conducted a cross-sectional analysis using provincial administrative data and publically available data for 31 First Nations communities to quantitatively examine any relationship between cultural continuity and diabetes prevalence. Cultural continuity, or "being who we are", is foundational to health in successful First Nations. Self-determination, or "being a self-sufficient Nation", stems from cultural continuity and is seriously compromised in today's Alberta Cree and Blackfoot Nations. Unfortunately, First Nations are in a continuous struggle with government policy. The intergenerational effects of colonization continue to impact the culture, which undermines the sense of self-determination, and contributes to diabetes and ill health. Crude diabetes prevalence varied dramatically among First Nations with values as low as 1.2% and as high as 18.3%. Those First Nations that appeared to have more cultural continuity (measured by traditional Indigenous language knowledge) had significantly lower diabetes prevalence after adjustment for socio-economic factors (p =0.007). First Nations that have been better able to preserve their culture may be relatively protected from diabetes.

Effects of a self-management education program on self-efficacy in patients with COPD: a mixed-methods sequential explanatory designed study

PubMed Central

Ng, Wai I; Smith, Graeme Drummond

2017-01-01

Background Self-management education programs (SMEPs) are potentially effective in the symptomatic management of COPD. Little is presently known about the effectiveness of these programs in Chinese COPD patients. The objective of this study was to evaluate the effectiveness of a specifically designed SMEP on levels of self-efficacy in Chinese patients with COPD. Materials and methods Based on the Medical Research Council framework for evaluating complex interventions, an exploratory phase randomized controlled trial was employed to examine the effects of an SMEP. Self-efficacy was the primary outcome using the COPD Self-efficacy Scale, measured at baseline and 6 months after the program. Qualitative data were sequentially collected from these patients via three focus groups to supplement the quantitative findings. Results The experimental group displayed significant improvement in their general self-efficacy (Z =−2.44, P=0.015) and specifically in confronting 1) physical exertion (Z =−2.57, P=0.01), 2) weather/environment effects (Z =−2.63, P<0.001) and 3) intense emotions (Z =−2.54, P=0.01). Three themes emerged from the focus groups: greater disease control, improved psychosocial well-being and perceived incapability and individuality. The connection of the quantitative and qualitative data demonstrated that individual perceptual constancy of patients could be a determining factor modulating the effectiveness of this type of intervention. Conclusion These findings highlight the potential putative benefits of an SMEP in Chinese patients with COPD. Further attention should be given to cultural considerations when developing this type of intervention in Chinese populations with COPD and other chronic diseases. PMID:28790816

Determinants of sexual intercourse initiation among incarcerated adolescents: a mixed-method study.

PubMed

Nik Farid, Nik Daliana; Che' Rus, Sulaiman; Dahlui, Maznah; Al-Sadat, Nabilla

2013-12-01

This study aimed to investigate the determinants of sexual intercourse initiation among incarcerated adolescents aged 12-19 years in Malaysia. This was a sequential mixed-method research project that was conducted in two phases. Quantitative and qualitative methods were used in the first and second phases, respectively. Data was collected via a survey using self-reported questionnaires from 1,082 adolescents, and from in-depth interviews and the written essays of 29 participants. The participants were recruited from 22 welfare institutions in peninsular Malaysia. Among the study participants, 483 were male and 599 were female. Overall, 62.3% of the incarcerated adolescents had initiated sexual intercourse at least once. The mean age at first sexual intercourse for both genders was 14.0 years. Individual factors found to be associated with previous sexual intercourse were the female gender (odds ratio [OR] 1.75; 95% confidence interval [CI] 1.11-2.74), previous alcohol use (OR 1.80; 95% CI 1.10-2.94), previous illicit drug use (OR 1.85; 95% CI 1.07-3.22), permissive attitude toward premarital sex (OR 4.34; 95% CI 2.17-8.70), and sexual abuse during childhood (OR 5.41; 95% CI 3.52-8.32). Qualitative findings revealed that the reasons for initiation of sexual intercourse among these adolescents were partner influence, inability to control sex drive, family issues, and the perception of sex as an expression of love. The determinants of sexual intercourse initiation among incarcerated Malaysian adolescents are comparable to those of developed countries. However, in Malaysia, sexual and reproductive health programmes for such adolescents should be tailored to address their specific needs.

Mind over bladder: Women, aging, and bladder health.

PubMed

Long, Joanna E; Khairat, Saif; Chmelo, Elizabeth; Palmer, Mary H

The purpose of this study was to explore the efficacy and acceptability of an innovative, electronically delivered self-management intervention for urinary incontinence (UI) that included daily mindfulness practice, completion of sequential bladder diaries, and bladder health education to improve UI in older women living independently in a retirement community. A mixed methods pilot study was conducted over ten weeks using a custom website or CD. Ten women were recruited and 8 completed the study; 5 of those (71%) experienced fewer daily UI episodes post intervention (p = 0.055). The women also reported a statistically significant decrease in the impact UI had on their everyday life (p = 0.04). Seventy-one percent (N = 5) reported subjective improvement in UI, and high acceptability scores also were achieved. The intervention was both effective in helping older women self-manage UI and acceptable to the population group. Further research is needed with a larger and diverse population of older women. Copyright © 2017 Elsevier Inc. All rights reserved.

Rural Industry Clustering Towards Transitional Rural-Urban Interface

NASA Astrophysics Data System (ADS)

Nugroho, P.

2018-05-01

Rural industrialization seems to be attractive for policymakers looking for counter-urbanization efforts – and nowadays peri-urbanization forces – in line with growing decentralized autonomy of local Indonesian authorities. To promote better rural development, an extended growth pole strategy has been introduced as well as an agropolitan approach and its derivatives. In fact, there is little evidence for their success; rural autonomy remains elusive instead. However, institutional capacity of rural authorities and organizations still fails to deliver rural development initiatives properly. This research was aimed at examining this issue by looking at rural industry clustering in the Greater Solo Region, Indonesia as a response against extended urbanization in peripheral regions. The study focused on batik industry clustering in the rural periphery of Solo City, which provides a transitional rural-urban interface necessary to drive rural independence. Having inherited the batik tradition underpinned by an agriculture-led peasant society, the rural batik industrialization has reinforced the socio-economic transition from a purely agrarian society to a mixed rural-urban society. This study employed an explanatory sequential mixed-method approach, where a quantitative spatial analysis was used to identify the expansion of urbanized areas in villages, and a qualitative case study analysis to figure out the socio-economic shift in rural livelihoods. The results showed that physical spatial changes in these villages do not conform to the socio-economic change into an urban industrial society in a substantial way. Rather, the local villagers preserve an informal economy to support the existence of a mixed rural-urban livelihood.

Usage and Usability of a Web-based Program for Family Caregivers of Older People in Three European Countries: A Mixed-Methods Evaluation.

PubMed

Barbabella, Francesco; Poli, Arianna; Hanson, Elizabeth; Andréasson, Frida; Salzmann, Benjamin; Döhner, Hanneli; Papa, Roberta; Efthymiou, Areti; Valenza, Silvia; Pelliccioni, Giuseppe; Lamura, Giovanni

2018-05-01

InformCare is a European Web platform that supports informal caregivers of older people by providing access to online information and professional and peer support. The aim of this study was to assess the usage and usability of a psychosocial Web-based program carried out in three European countries (Italy, Sweden, and Germany). A mixed-methods sequential explanatory design was adopted, comprising baseline and postintervention assessments, as well as combined thematic content analysis of results and focus group findings. A convenience sample of 118 caregivers was enrolled, of whom 94 used the services offered by the program at least once. The subsamples in the three countries used the platform in different ways, with a predominance of passive strategies (eg, seeking information and reading other people's comments) for Italian caregivers, and more active usage by Swedish and German caregivers. The usability assessment showed that the platform was perceived well by Italian and German caregivers, whereas technical problems affected the Swedish sample's experiences. Focus group data highlighted user satisfaction with the online support and reliability of the environment. Recommendations for practitioners are to ensure digital training for caregivers who have lower confidence in use of the Internet, to involve different healthcare professionals in the provision of professional support, and to adequately manage online community building.

A salutogenic approach to prevention of metabolic syndrome: a mixed methods population study.

PubMed

Miettola, Juhani; Viljanen, Anna Maria

2014-12-01

To find a salutogenic approach for prevention of metabolic syndrome in primary care practice. An explanatory sequential mixed-methods procedure was used to find salutogenic approaches for lifestyle change by assessing individual need, potential, and personal motivation. Data from a population health survey and interviews that focused on a sense of coherence were analysed. Altogether 480 Finnish subjects participated in a population health survey, and 43 of them were interviewed. The 43 interviewees' data were included in the final analysis. With the health survey participants' liability for MetS was assessed, and the objective need for lifestyle intervention was determined. Through the focused interviews potential and personal motivation for lifestyle modification were explored. Finally the data of the 43 interviewed subjects were merged. Four possible lifestyle intervention approaches were identified for specific intervention. First, subjects with a strong sense of coherence only need encouragement to maintain a healthy lifestyle; second, professional support was found important for subjects with gaps in health awareness to improve health understanding; third, strengthening of social support for lifestyle change is necessary for subjects with various practical constraints in their everyday life; and fourth, strengthening of stress adaptation is important for subjects with redundant concerns about their health. Salutogenic client-centred lifestyle modification approaches should be part of primary care practice. Further, a cross-disciplinary approach is needed in primary care research and practice to combat the exploding lifestyle illnesses.

Effective components of exercise and physical activity-related behaviour-change interventions for chronic non-communicable diseases in Africa: protocol for a systematic mixed studies review with meta-analysis

PubMed Central

Igwesi-Chidobe, Chinonso N; Godfrey, Emma L; Kengne, Andre P

2015-01-01

Introduction Chronic non-communicable diseases (NCDs) account for a high burden of mortality and morbidity in Africa. Evidence-based clinical guidelines recommend exercise training and promotion of physical activity behaviour changes to control NCDs. Developing such interventions in Africa requires an understanding of the essential components that make them effective in this context. This is a protocol for a systematic mixed studies review that aims to determine the effective components of exercise and physical activity-related behaviour-change interventions for chronic diseases in Africa, by combining quantitative and qualitative research evidence from studies published until July 2015. Methods and analysis We will conduct a detailed search to identify all published and unpublished studies that assessed the effects of exercise and physical activity-related interventions or the experiences/perspectives of patients to these interventions for NCDs from bibliographic databases and the grey literature. Bibliographic databases include MEDLINE, EMBASE, CENTRAL (Cochrane Central Register of Controlled Trials), PsycINFO, CINAHL and Web of Science. We will include the following African regional databases: African Index Medicus (AIM) and AFROLIB, which is the WHO's regional office database for Africa. The databases will be searched from inception until 18 July 2015. Appraisal of study quality will be performed after results synthesis. Data synthesis will be performed independently for quantitative and qualitative data using a mixed methods sequential explanatory synthesis for systematic mixed studies reviews. Meta-analysis will be conducted for the quantitative studies, and thematic synthesis for qualitative studies and qualitative results from the non-controlled observational studies. The primary outcome will include exercise adherence and physical activity behaviour changes. This review protocol is reported according to Preferred Reporting Items for Systematic reviews and Meta-Analysis protocols (PRISMA-P) 2015 guidelines. Ethics and dissemination There is no ethical requirement for this study, as it utilises published data. This review is expected to inform the development of exercise and physical activity-related behaviour-change interventions in Africa, and will be presented at conferences, and published in peer reviewed journals and a PhD thesis at King's College London. Protocol registration number This study was registered with the International Prospective Register of Systematic Reviews (PROSPERO) on 22 January 2015 (registration number: PROSPERO 2015: CRD42015016084). PMID:26270945

Determination of ambroxol hydrochloride, methylparaben and benzoic acid in pharmaceutical preparations based on sequential injection technique coupled with monolithic column.

PubMed

Satínský, Dalibor; Huclová, Jitka; Ferreira, Raquel L C; Montenegro, Maria Conceição B S M; Solich, Petr

2006-02-13

The porous monolithic columns show high performance at relatively low pressure. The coupling of short monoliths with sequential injection technique (SIA) results in a new approach to implementation of separation step to non-separation low-pressure method. In this contribution, a new separation method for simultaneous determination of ambroxol, methylparaben and benzoic acid was developed based on a novel reversed-phase sequential injection chromatography (SIC) technique with UV detection. A Chromolith SpeedROD RP-18e, 50-4.6 mm column with 10 mm precolumn and a FIAlab 3000 system with a six-port selection valve and 5 ml syringe were used for sequential injection chromatographic separations in our study. The mobile phase used was acetonitrile-tetrahydrofuran-0.05M acetic acid (10:10:90, v/v/v), pH 3.75 adjusted with triethylamine, flow rate 0.48 mlmin(-1), UV-detection was at 245 nm. The analysis time was <11 min. A new SIC method was validated and compared with HPLC. The method was found to be useful for the routine analysis of the active compounds ambroxol and preservatives (methylparaben or benzoic acid) in various pharmaceutical syrups and drops.

An extended sequential goodness-of-fit multiple testing method for discrete data.

PubMed

Castro-Conde, Irene; Döhler, Sebastian; de Uña-Álvarez, Jacobo

2017-10-01

The sequential goodness-of-fit (SGoF) multiple testing method has recently been proposed as an alternative to the familywise error rate- and the false discovery rate-controlling procedures in high-dimensional problems. For discrete data, the SGoF method may be very conservative. In this paper, we introduce an alternative SGoF-type procedure that takes into account the discreteness of the test statistics. Like the original SGoF, our new method provides weak control of the false discovery rate/familywise error rate but attains false discovery rate levels closer to the desired nominal level, and thus it is more powerful. We study the performance of this method in a simulation study and illustrate its application to a real pharmacovigilance data set.

Sequential Pharmacotherapy for Children with Comorbid Attention-Deficit/hyperactivity and Anxiety Disorders.

ERIC Educational Resources Information Center

Abikoff, Howard; McGough, James; Vitiello, Benedetto; McCracken, James; Davies, Mark; Walkup, John; Riddle, Mark; Oatis, Melvin; Greenhill, Laurence; Skrobala, Anne; March, John; Gammon, Pat; Robinson, James; Lazell, Robert; McMahon, Donald J.; Ritz, Louise

2005-01-01

Objective: Attention-deficit/hyperactivity disorder (ADHD) is often accompanied by clinically significant anxiety, but few empirical data guide treatment of children meeting full DSM-IV criteria for ADHD and anxiety disorders (ADHD/ANX). This study examined the efficacy of sequential pharmacotherapy for ADHD/ANX children. Method: Children, age 6…

Microwave Ablation: Comparison of Simultaneous and Sequential Activation of Multiple Antennas in Liver Model Systems.

PubMed

Harari, Colin M; Magagna, Michelle; Bedoya, Mariajose; Lee, Fred T; Lubner, Meghan G; Hinshaw, J Louis; Ziemlewicz, Timothy; Brace, Christopher L

2016-01-01

To compare microwave ablation zones created by using sequential or simultaneous power delivery in ex vivo and in vivo liver tissue. All procedures were approved by the institutional animal care and use committee. Microwave ablations were performed in both ex vivo and in vivo liver models with a 2.45-GHz system capable of powering up to three antennas simultaneously. Two- and three-antenna arrays were evaluated in each model. Sequential and simultaneous ablations were created by delivering power (50 W ex vivo, 65 W in vivo) for 5 minutes per antenna (10 and 15 minutes total ablation time for sequential ablations, 5 minutes for simultaneous ablations). Thirty-two ablations were performed in ex vivo bovine livers (eight per group) and 28 in the livers of eight swine in vivo (seven per group). Ablation zone size and circularity metrics were determined from ablations excised postmortem. Mixed effects modeling was used to evaluate the influence of power delivery, number of antennas, and tissue type. On average, ablations created by using the simultaneous power delivery technique were larger than those with the sequential technique (P < .05). Simultaneous ablations were also more circular than sequential ablations (P = .0001). Larger and more circular ablations were achieved with three antennas compared with two antennas (P < .05). Ablations were generally smaller in vivo compared with ex vivo. The use of multiple antennas and simultaneous power delivery creates larger, more confluent ablations with greater temperatures than those created with sequential power delivery. © RSNA, 2015.

A D-vine copula-based model for repeated measurements extending linear mixed models with homogeneous correlation structure.

PubMed

Killiches, Matthias; Czado, Claudia

2018-03-22

We propose a model for unbalanced longitudinal data, where the univariate margins can be selected arbitrarily and the dependence structure is described with the help of a D-vine copula. We show that our approach is an extremely flexible extension of the widely used linear mixed model if the correlation is homogeneous over the considered individuals. As an alternative to joint maximum-likelihood a sequential estimation approach for the D-vine copula is provided and validated in a simulation study. The model can handle missing values without being forced to discard data. Since conditional distributions are known analytically, we easily make predictions for future events. For model selection, we adjust the Bayesian information criterion to our situation. In an application to heart surgery data our model performs clearly better than competing linear mixed models. © 2018, The International Biometric Society.

A Sequential Optimization Sampling Method for Metamodels with Radial Basis Functions

PubMed Central

Pan, Guang; Ye, Pengcheng; Yang, Zhidong

2014-01-01

Metamodels have been widely used in engineering design to facilitate analysis and optimization of complex systems that involve computationally expensive simulation programs. The accuracy of metamodels is strongly affected by the sampling methods. In this paper, a new sequential optimization sampling method is proposed. Based on the new sampling method, metamodels can be constructed repeatedly through the addition of sampling points, namely, extrema points of metamodels and minimum points of density function. Afterwards, the more accurate metamodels would be constructed by the procedure above. The validity and effectiveness of proposed sampling method are examined by studying typical numerical examples. PMID:25133206

Characterization of mathematics instructional practises for prospective elementary teachers with varying levels of self-efficacy in classroom management and mathematics teaching

NASA Astrophysics Data System (ADS)

Lee, Carrie W.; Walkowiak, Temple A.; Nietfeld, John L.

2017-03-01

The purpose of this study was to investigate the relationship between prospective teachers' (PTs) instructional practises and their efficacy beliefs in classroom management and mathematics teaching. A sequential, explanatory mixed-methods design was employed. Results from efficacy surveys, implemented with 54 PTs were linked to a sample of teachers' instructional practises during the qualitative phase. In this phase, video-recorded lessons were analysed based on tasks, representations, discourse, and classroom management. Findings indicate that PTs with higher levels of mathematics teaching efficacy taught lessons characterised by tasks of higher cognitive demand, extended student explanations, student-to-student discourse, and explicit connections between representations. Classroom management efficacy seems to bear influence on the utilised grouping structures. These findings support explicit attention to PTs' mathematics teaching and classroom management efficacy throughout teacher preparation and a need for formative feedback to inform development of beliefs about teaching practises.

The effect of a sequential structure of practice for the training of perceptual-cognitive skills in tennis

PubMed Central

2017-01-01

Objective Anticipation of opponent actions, through the use of advanced (i.e., pre-event) kinematic information, can be trained using video-based temporal occlusion. Typically, this involves isolated opponent skills/shots presented as trials in a random order. However, two different areas of research concerning representative task design and contextual (non-kinematic) information, suggest this structure of practice restricts expert performance. The aim of this study was to examine the effect of a sequential structure of practice during video-based training of anticipatory behavior in tennis, as well as the transfer of these skills to the performance environment. Methods In a pre-practice-retention-transfer design, participants viewed life-sized video of tennis rallies across practice in either a sequential order (sequential group), in which participants were exposed to opponent skills/shots in the order they occur in the sport, or a non-sequential (non-sequential group) random order. Results In the video-based retention test, the sequential group was significantly more accurate in their anticipatory judgments when the retention condition replicated the sequential structure compared to the non-sequential group. In the non-sequential retention condition, the non-sequential group was more accurate than the sequential group. In the field-based transfer test, overall decision time was significantly faster in the sequential group compared to the non-sequential group. Conclusion Findings highlight the benefits of a sequential structure of practice for the transfer of anticipatory behavior in tennis. We discuss the role of contextual information, and the importance of representative task design, for the testing and training of perceptual-cognitive skills in sport. PMID:28355263

Sequential ensemble-based optimal design for parameter estimation: SEQUENTIAL ENSEMBLE-BASED OPTIMAL DESIGN

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

Man, Jun; Zhang, Jiangjiang; Li, Weixuan

2016-10-01

The ensemble Kalman filter (EnKF) has been widely used in parameter estimation for hydrological models. The focus of most previous studies was to develop more efficient analysis (estimation) algorithms. On the other hand, it is intuitively understandable that a well-designed sampling (data-collection) strategy should provide more informative measurements and subsequently improve the parameter estimation. In this work, a Sequential Ensemble-based Optimal Design (SEOD) method, coupled with EnKF, information theory and sequential optimal design, is proposed to improve the performance of parameter estimation. Based on the first-order and second-order statistics, different information metrics including the Shannon entropy difference (SD), degrees ofmore » freedom for signal (DFS) and relative entropy (RE) are used to design the optimal sampling strategy, respectively. The effectiveness of the proposed method is illustrated by synthetic one-dimensional and two-dimensional unsaturated flow case studies. It is shown that the designed sampling strategies can provide more accurate parameter estimation and state prediction compared with conventional sampling strategies. Optimal sampling designs based on various information metrics perform similarly in our cases. The effect of ensemble size on the optimal design is also investigated. Overall, larger ensemble size improves the parameter estimation and convergence of optimal sampling strategy. Although the proposed method is applied to unsaturated flow problems in this study, it can be equally applied in any other hydrological problems.« less

Professionalisation and social attitudes: a protocol for measuring changes in HIV/AIDS-related stigma among healthcare students

PubMed Central

Ahmadi, Keivan; Reidpath, Daniel D; Allotey, Pascale; Hassali, Mohamed Azmi Ahmad

2013-01-01

Introduction HIV/AIDS-related stigma affects the access and utilisation of health services. Although HIV/AIDS-related stigma in the health services has been studied, little work has attended to the relationship between professional development and stigmatising attitudes. Hence, in this study, we will extend earlier research by examining the relationship between the stage of professional development and the kinds of stigmatising attitudes held about people living with HIV/AIDS. Methods and analysis A serial cross-sectional design will be combined with a two-point in time longitudinal design to measure the levels of stigma among healthcare students from each year of undergraduate and graduate courses in Malaysia and Australia. In the absence of suitable measures, we will carry out a sequential mixed methods design to develop such a tool. The questionnaire data will be analysed using mixed effects linear models to manage the repeated measures. Ethics and dissemination We have received ethical approval from the Monash MBBS executive committee as well as the Monash University Human Research Ethics Committee. We will keep the data in a locked filing cabinet in the Monash University (Sunway campus) premises for 5 years, after which the information will be shredded and disposed of in secure bins, and digital recordings will be erased in accordance with Monash University's regulations. Only the principal investigator and the researcher will have access to the filing cabinet. We aim to present and publish the results of this study in national and international conferences and peer-reviewed journals, respectively. PMID:23793653

A parallel metaheuristic for large mixed-integer dynamic optimization problems, with applications in computational biology.

PubMed

Penas, David R; Henriques, David; González, Patricia; Doallo, Ramón; Saez-Rodriguez, Julio; Banga, Julio R

2017-01-01

We consider a general class of global optimization problems dealing with nonlinear dynamic models. Although this class is relevant to many areas of science and engineering, here we are interested in applying this framework to the reverse engineering problem in computational systems biology, which yields very large mixed-integer dynamic optimization (MIDO) problems. In particular, we consider the framework of logic-based ordinary differential equations (ODEs). We present saCeSS2, a parallel method for the solution of this class of problems. This method is based on an parallel cooperative scatter search metaheuristic, with new mechanisms of self-adaptation and specific extensions to handle large mixed-integer problems. We have paid special attention to the avoidance of convergence stagnation using adaptive cooperation strategies tailored to this class of problems. We illustrate its performance with a set of three very challenging case studies from the domain of dynamic modelling of cell signaling. The simpler case study considers a synthetic signaling pathway and has 84 continuous and 34 binary decision variables. A second case study considers the dynamic modeling of signaling in liver cancer using high-throughput data, and has 135 continuous and 109 binaries decision variables. The third case study is an extremely difficult problem related with breast cancer, involving 690 continuous and 138 binary decision variables. We report computational results obtained in different infrastructures, including a local cluster, a large supercomputer and a public cloud platform. Interestingly, the results show how the cooperation of individual parallel searches modifies the systemic properties of the sequential algorithm, achieving superlinear speedups compared to an individual search (e.g. speedups of 15 with 10 cores), and significantly improving (above a 60%) the performance with respect to a non-cooperative parallel scheme. The scalability of the method is also good (tests were performed using up to 300 cores). These results demonstrate that saCeSS2 can be used to successfully reverse engineer large dynamic models of complex biological pathways. Further, these results open up new possibilities for other MIDO-based large-scale applications in the life sciences such as metabolic engineering, synthetic biology, drug scheduling.

Tested Demonstrations.

ERIC Educational Resources Information Center

Gilbert, George L., Ed.

1983-01-01

Presents background information and procedures for producing sequential color reactions. With proper selection of pH indicator dyes, most school colors can be produced after mixing colorless solutions. Procedures for producing white/purple and red/white/blue colors are outlined. Also outlines preparation of 2, 4, 2', 4',…

Delay test generation for synchronous sequential circuits

NASA Astrophysics Data System (ADS)

Devadas, Srinivas

1989-05-01

We address the problem of generating tests for delay faults in non-scan synchronous sequential circuits. Delay test generation for sequential circuits is a considerably more difficult problem than delay testing of combinational circuits and has received much less attention. In this paper, we present a method for generating test sequences to detect delay faults in sequential circuits using the stuck-at fault sequential test generator STALLION. The method is complete in that it will generate a delay test sequence for a targeted fault given sufficient CPU time, if such a sequence exists. We term faults for which no delay test sequence exists, under out test methodology, sequentially delay redundant. We describe means of eliminating sequential delay redundancies in logic circuits. We present a partial-scan methodology for enhancing the testability of difficult-to-test of untestable sequential circuits, wherein a small number of flip-flops are selected and made controllable/observable. The selection process guarantees the elimination of all sequential delay redundancies. We show that an intimate relationship exists between state assignment and delay testability of a sequential machine. We describe a state assignment algorithm for the synthesis of sequential machines with maximal delay fault testability. Preliminary experimental results using the test generation, partial-scan and synthesis algorithm are presented.

Beyond Grand Rounds: A Comprehensive and Sequential Intervention to Improve Identification of Delirium

ERIC Educational Resources Information Center

Ramaswamy, Ravishankar; Dix, Edward F.; Drew, Janet E.; Diamond, James J.; Inouye, Sharon K.; Roehl, Barbara J. O.

2011-01-01

Purpose of the Study: Delirium is a widespread concern for hospitalized seniors, yet is often unrecognized. A comprehensive and sequential intervention (CSI) aiming to effect change in clinician behavior by improving knowledge about delirium was tested. Design and Methods: A 2-day CSI program that consisted of progressive 4-part didactic series,…

How College Students' Conceptions of Newton's Second and Third Laws Change Through Watching Interactive Video Vignettes: A Mixed Methods Study

NASA Astrophysics Data System (ADS)

Engelman, Jonathan

Changing student conceptions in physics is a difficult process and has been a topic of research for many years. The purpose of this study was to understand what prompted students to change or not change their incorrect conceptions of Newtons Second or Third Laws in response to an intervention, Interactive Video Vignettes (IVVs), designed to overcome them. This study is based on prior research reported in the literature which has found that a curricular framework of elicit, confront, resolve, and reflect (ECRR) is important for changing student conceptions (McDermott, 2001). This framework includes four essential parts such that during an instructional event student conceptions should be elicited, incorrect conceptions confronted, these conflicts resolved, and then students should be prompted to reflect on their learning. Twenty-two undergraduate student participants who completed either or both IVVs were studied to determine whether or not they experienced components of the ECRR framework at multiple points within the IVVs. A fully integrated, mixed methods design was used to address the study purpose. Both quantitative and qualitative data were collected iteratively for each participant. Successive data collections were informed by previous data collections. All data were analyzed concurrently. The quantitative strand included a pre/post test that participants took before and after completing a given IVV and was used to measure the effect of each IVV on learning. The qualitative strand included video of each participant completing the IVV as well as an audio-recorded video elicitation interview after the post-test. The qualitative data collection was designed to describe student experiences with each IVV as well as to observe how the ECRR framework was experienced. Collecting and analyzing data using this mixed methods approach helped develop a more complete understanding of how student conceptions of Newtons Second and Third Laws changed through completion of IVVs and how the ECRR framework was experienced. In answering the research questions, two major conclusions were reached: (1) while the ECRR framework was experienced in both the Newtons 2nd Law and Newtons 3rd Law IVVs, these experiences were qualitatively different from each other and these differences help support the differences in gain scores on the post-tests for the participants; and (2) both IVVs were able to change certain misconceptions associated with either Newtons 2nd or 3rd laws more than others. Therefore, in researching student experiences while completing the Newtons 2nd Law and Newtons 3rd Law IVVs, I determined that a complete, sequential experience of the elicit, confront, resolve, reflect framework led to the greatest change in student conceptions. This dissertation adds to the field of physics education through finding the positive impact of the ECRR framework, as IVVs are still being created and disseminated. Physics educators and researchers interested in conceptual change can use these findings to provide evidence on what students think when interacting with videos designed to change their conceptions. Finally, this dissertation supports the conceptual change literature in that the full, sequential experience involving each component of the ECRR framework led to a change in student conceptions.

Analysis of Optimal Sequential State Discrimination for Linearly Independent Pure Quantum States.

PubMed

Namkung, Min; Kwon, Younghun

2018-04-25

Recently, J. A. Bergou et al. proposed sequential state discrimination as a new quantum state discrimination scheme. In the scheme, by the successful sequential discrimination of a qubit state, receivers Bob and Charlie can share the information of the qubit prepared by a sender Alice. A merit of the scheme is that a quantum channel is established between Bob and Charlie, but a classical communication is not allowed. In this report, we present a method for extending the original sequential state discrimination of two qubit states to a scheme of N linearly independent pure quantum states. Specifically, we obtain the conditions for the sequential state discrimination of N = 3 pure quantum states. We can analytically provide conditions when there is a special symmetry among N = 3 linearly independent pure quantum states. Additionally, we show that the scenario proposed in this study can be applied to quantum key distribution. Furthermore, we show that the sequential state discrimination of three qutrit states performs better than the strategy of probabilistic quantum cloning.

Treatment of synthetic refinery wastewater in anoxic-aerobic sequential moving bed reactors and sulphur recovery.

PubMed

Mallick, Subrat Kumar; Chakraborty, Saswati

2017-11-10

Objective of the present study was to simultaneously biodegrade synthetic petroleum refinery wastewater containing phenol (750 mg/L), sulphide (750 mg/L), hydrocarbon (as emulsified diesel of 300 mg/L), ammonia-nitrogen (350 mg/L) at pH >9 in anoxic-aerobic sequential moving bed reactors. The optimum mixing speed of anoxic reactor was observed at 20 rpm and beyond that, removal rate remained constant. In anoxic reactor the minimum hydraulic retention time was observed to be 2 days for complete removal of sulphide, 40-50% removal of phenol and total hydrocarbons and 52% of sulphur recovery. The optimum HRT of aerobic moving bed reactor was observed as 16 h (total HRT of 64 h for anoxic and aerobic reactors) for complete removals of phenol, total hydrocarbons, COD (chemical oxygen demand) and ammonia-nitrogen with nitrification.

Experiences of general practitioners, home care nurses, physiotherapists and seniors involved in a multidisciplinary home-based fall prevention programme: a mixed method study.

PubMed

Amacher, Astrid E; Nast, Irina; Zindel, Barbara; Schmid, Lukas; Krafft, Valérie; Niedermann, Karin

2016-09-05

The feasibility of effective fall prevention programmes (FPPs) for use in daily clinical practice needs to be assessed in the specific healthcare settings. The aim of this study was to explore the perceived benefits and barriers of an evidence-based, home-based pilot FPP among the involved seniors, general practitioners (GPs), home care nurses (HCNs) and physiotherapists (PTs), in order to develop tailored implementation strategies. The study was a mixed method study using an 'exploratory sequential design'. In the initial qualitative sequence, semi-structured interviews were performed with four participants from each group and analysed using a deductive content analysis. In the successive quantitative sequence, target group specific postal surveys were conducted with all participants. The triangulation of both steps allowed merging the in-depth experiences from the interviews with the general findings from the survey. In this evaluation study participated 17 seniors (mean age 79.7 (SD +/-6.2) years). 40 GPs, 12 HCNs and four PTs. All were satisfied with the organization and processes of the FPP. The main benefit, perceived by each target group, was the usefulness of the FPP in detecting risk of falling at the senior's home. A low number of recruiting GPs and HCNs, divergent opinions of the health professionals towards the aim of the FPP as well as no perceived need for changes by the seniors were the most important barriers to the participation of (more) seniors. Multidisciplinary home-based fall prevention is a useful approach to detect the risk of falling in seniors. The barriers identified need to be resolved through tailored strategies to facilitate the successful nationwide implementation of this pilot FPP.

Sequential Testing: Basics and Benefits

DTIC Science & Technology

1978-03-01

Eii~TARADC6M and x _..TECHNICAL REPORT NO. 12325 SEQUENTIAL TESTING: BASICS AND BENEFITS / i * p iREFERENCE CP...Sequential Testing: Basics and Benefits Contents Page I. Introduction and Summary II. Sequential Analysis 2 III. Mathematics of Sequential Testing 4 IV...testing. The added benefit of reduced energy needs are inherent in this testing method. The text was originally released by the authors in 1972. The text

Sequential Designs Based on Bayesian Uncertainty Quantification in Sparse Representation Surrogate Modeling

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

Chen, Ray -Bing; Wang, Weichung; Jeff Wu, C. F.

A numerical method, called OBSM, was recently proposed which employs overcomplete basis functions to achieve sparse representations. While the method can handle non-stationary response without the need of inverting large covariance matrices, it lacks the capability to quantify uncertainty in predictions. We address this issue by proposing a Bayesian approach which first imposes a normal prior on the large space of linear coefficients, then applies the MCMC algorithm to generate posterior samples for predictions. From these samples, Bayesian credible intervals can then be obtained to assess prediction uncertainty. A key application for the proposed method is the efficient construction ofmore » sequential designs. Several sequential design procedures with different infill criteria are proposed based on the generated posterior samples. As a result, numerical studies show that the proposed schemes are capable of solving problems of positive point identification, optimization, and surrogate fitting.« less

Sequential Designs Based on Bayesian Uncertainty Quantification in Sparse Representation Surrogate Modeling

DOE PAGES

Chen, Ray -Bing; Wang, Weichung; Jeff Wu, C. F.

2017-04-12

A numerical method, called OBSM, was recently proposed which employs overcomplete basis functions to achieve sparse representations. While the method can handle non-stationary response without the need of inverting large covariance matrices, it lacks the capability to quantify uncertainty in predictions. We address this issue by proposing a Bayesian approach which first imposes a normal prior on the large space of linear coefficients, then applies the MCMC algorithm to generate posterior samples for predictions. From these samples, Bayesian credible intervals can then be obtained to assess prediction uncertainty. A key application for the proposed method is the efficient construction ofmore » sequential designs. Several sequential design procedures with different infill criteria are proposed based on the generated posterior samples. As a result, numerical studies show that the proposed schemes are capable of solving problems of positive point identification, optimization, and surrogate fitting.« less

Waste treatment process for removal of contaminants from aqueous, mixed-waste solutions using sequential chemical treatment and crossflow microfiltration, followed by dewatering

DOEpatents

Vijayan, S.; Wong, C.F.; Buckley, L.P.

1994-11-22

In processes of this invention aqueous waste solutions containing a variety of mixed waste contaminants are treated to remove the contaminants by a sequential addition of chemicals and adsorption/ion exchange powdered materials to remove the contaminants including lead, cadmium, uranium, cesium-137, strontium-85/90, trichloroethylene and benzene, and impurities including iron and calcium. Staged conditioning of the waste solution produces a polydisperse system of size enlarged complexes of the contaminants in three distinct configurations: water-soluble metal complexes, insoluble metal precipitation complexes, and contaminant-bearing particles of ion exchange and adsorbent materials. The volume of the waste is reduced by separation of the polydisperse system by cross-flow microfiltration, followed by low-temperature evaporation and/or filter pressing. The water produced as filtrate is discharged if it meets a specified target water quality, or else the filtrate is recycled until the target is achieved. 1 fig.

Waste treatment process for removal of contaminants from aqueous, mixed-waste solutions using sequential chemical treatment and crossflow microfiltration, followed by dewatering

DOEpatents

Vijayan, Sivaraman; Wong, Chi F.; Buckley, Leo P.

1994-01-01

In processes of this invention aqueous waste solutions containing a variety of mixed waste contaminants are treated to remove the contaminants by a sequential addition of chemicals and adsorption/ion exchange powdered materials to remove the contaminants including lead, cadmium, uranium, cesium-137, strontium-85/90, trichloroethylene and benzene, and impurities including iron and calcium. Staged conditioning of the waste solution produces a polydisperse system of size enlarged complexes of the contaminants in three distinct configurations: water-soluble metal complexes, insoluble metal precipitation complexes, and contaminant-bearing particles of ion exchange and adsorbent materials. The volume of the waste is reduced by separation of the polydisperse system by cross-flow microfiltration, followed by low-temperature evaporation and/or filter pressing. The water produced as filtrate is discharged if it meets a specified target water quality, or else the filtrate is recycled until the target is achieved.

Sequential slip transfer of mixed-character dislocations across Σ3 coherent twin boundary in FCC metals: a concurrent atomistic-continuum study

DOE PAGES

Xu, Shuozhi; Xiong, Liming; Chen, Youping; ...

2016-01-29

Sequential slip transfer across grain boundaries (GB) has an important role in size-dependent propagation of plastic deformation in polycrystalline metals. For example, the Hall–Petch effect, which states that a smaller average grain size results in a higher yield stress, can be rationalised in terms of dislocation pile-ups against GBs. In spite of extensive studies in modelling individual phases and grains using atomistic simulations, well-accepted criteria of slip transfer across GBs are still lacking, as well as models of predicting irreversible GB structure evolution. Slip transfer is inherently multiscale since both the atomic structure of the boundary and the long-range fieldsmore » of the dislocation pile-up come into play. In this work, concurrent atomistic-continuum simulations are performed to study sequential slip transfer of a series of curved dislocations from a given pile-up on Σ3 coherent twin boundary (CTB) in Cu and Al, with dominant leading screw character at the site of interaction. A Frank-Read source is employed to nucleate dislocations continuously. It is found that subject to a shear stress of 1.2 GPa, screw dislocations transfer into the twinned grain in Cu, but glide on the twin boundary plane in Al. Moreover, four dislocation/CTB interaction modes are identified in Al, which are affected by (1) applied shear stress, (2) dislocation line length, and (3) dislocation line curvature. Our results elucidate the discrepancies between atomistic simulations and experimental observations of dislocation-GB reactions and highlight the importance of directly modeling sequential dislocation slip transfer reactions using fully 3D models.« less

Sequential slip transfer of mixed-character dislocations across Σ3 coherent twin boundary in FCC metals: a concurrent atomistic-continuum study

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

Xu, Shuozhi; Xiong, Liming; Chen, Youping

Sequential slip transfer across grain boundaries (GB) has an important role in size-dependent propagation of plastic deformation in polycrystalline metals. For example, the Hall–Petch effect, which states that a smaller average grain size results in a higher yield stress, can be rationalised in terms of dislocation pile-ups against GBs. In spite of extensive studies in modelling individual phases and grains using atomistic simulations, well-accepted criteria of slip transfer across GBs are still lacking, as well as models of predicting irreversible GB structure evolution. Slip transfer is inherently multiscale since both the atomic structure of the boundary and the long-range fieldsmore » of the dislocation pile-up come into play. In this work, concurrent atomistic-continuum simulations are performed to study sequential slip transfer of a series of curved dislocations from a given pile-up on Σ3 coherent twin boundary (CTB) in Cu and Al, with dominant leading screw character at the site of interaction. A Frank-Read source is employed to nucleate dislocations continuously. It is found that subject to a shear stress of 1.2 GPa, screw dislocations transfer into the twinned grain in Cu, but glide on the twin boundary plane in Al. Moreover, four dislocation/CTB interaction modes are identified in Al, which are affected by (1) applied shear stress, (2) dislocation line length, and (3) dislocation line curvature. Our results elucidate the discrepancies between atomistic simulations and experimental observations of dislocation-GB reactions and highlight the importance of directly modeling sequential dislocation slip transfer reactions using fully 3D models.« less

Parents' Verbal and Nonverbal Caring Behaviors and Child Distress During Cancer-Related Port Access Procedures: A Time-Window Sequential Analysis.

PubMed

Bai, Jinbing; Harper, Felicity W K; Penner, Louis A; Swanson, Kristen; Santacroce, Sheila J

2017-11-01

To study the relationship between parental verbal and nonverbal caring behaviors and child distress during cancer-related port access placement using correlational and time-window sequential analyses.
. Longitudinal, observational design.
. Children's Hospital of Michigan and St. Jude Children's Research Hospital.
. 43 child-parent dyads, each with two or three video recordings of the child undergoing cancer-related port placement.
. Two trained raters coded parent interaction behaviors and child distress using the Parent Caring Response Scoring System and Karmanos Child Coping and Distress Scale, respectively. Mixed modeling with generalized estimating equations examined the associations between parent interaction behaviors and parent distress, child distress, and child cooperation reported by multiple raters. Time-window sequential analyses were performed to investigate the temporal relationships in parent-child interactions within a five-second window.
. Parent caring behaviors, child distress, and child cooperation.
. Parent caring interaction behaviors were significantly correlated with parent distress, child distress, and child cooperation during repeated cancer port accessing. Sequential analyses showed that children were significantly less likely to display behavioral and verbal distress following parent caring behaviors than at any other time. If a child is already distressed, parent verbal and nonverbal caring behaviors can significantly reduce child behavioral and verbal distress.
. Parent caring behaviors, particularly the rarely studied nonverbal behaviors (e.g., eye contact, distance close to touch, supporting/allowing), can reduce the child's distress during cancer port accessing procedures.
. Studying parent-child interactions during painful cancer-related procedures can provide evidence to develop nursing interventions to support parents in caring for their child during painful procedures.

A mixed-methods study on perceptions towards use of Rapid Ethical Assessment to improve informed consent processes for health research in a low-income setting

PubMed Central

2014-01-01

Background Rapid Ethical Assessment (REA) is a form of rapid ethnographic assessment conducted at the beginning of research project to guide the consent process with the objective of reconciling universal ethical guidance with specific research contexts. The current study is conducted to assess the perceived relevance of introducing REA as a mainstream tool in Ethiopia. Methods Mixed methods research using a sequential explanatory approach was conducted from July to September 2012, including 241 cross-sectional, self-administered and 19 qualitative, in-depth interviews among health researchers and regulators including ethics committee members in Ethiopian health research institutions and universities. Results In their evaluation of the consent process, only 40.2% thought that the consent process and information given were adequately understood by study participants; 84.6% claimed they were not satisfied with the current consent process and 85.5% thought the best interests of study participants were not adequately considered. Commonly mentioned consent-related problems included lack of clarity (48.1%), inadequate information (34%), language barriers (28.2%), cultural differences (27.4%), undue expectations (26.6%) and power imbalances (20.7%). About 95.4% believed that consent should be contextualized to the study setting and 39.4% thought REA would be an appropriate approach to improve the perceived problems. Qualitative findings helped to further explore the gaps identified in the quantitative findings and to map-out concerns related to the current research consent process in Ethiopia. Suggestions included, conducting REA during the pre-test (pilot) phase of studies when applicable. The need for clear guidance for researchers on issues such as when and how to apply the REA tools was stressed. Conclusion The study findings clearly indicated that there are perceived to be correctable gaps in the consent process of medical research in Ethiopia. REA is considered relevant by researchers and stakeholders to address these gaps. Exploring further the feasibility and applicability of REA is recommended. PMID:24885049

Understanding and scaffolding Danish schoolteachers’ motivation for using classroom-based physical activity: study protocol for a mixed methods study

PubMed Central

Skovgaard, Thomas; Bredahl, Thomas

2018-01-01

Introduction The benefits of physical activity for children’s health, both mental and physical, and its positive effects on academic achievement are well established. Research also emphasises that schools could provide a natural setting for regular physical activity. There is, however, a limited amount of knowledge about teachers’ views when it comes to integrating physical activity as part of teaching. The aim of this study is to understand teachers’ motivation for integrating physical activity as part of teaching and to assess their need for guidance and support. Methods and analysis The study uses an explanatory sequential mixed-methods design. Schools from across Denmark are included in the sample. The design comprises two separated phases—a quantitative and qualitative phase. The quantitative phase is guided by the self-determination theory where teachers’ motivation will be measured using the Work Task Motivation Scale for Teachers. The theory of scaffolding guides the qualitative phase, which consists of in-depth interviews with participants selected from the quantitative phase based on levels of motivation and on demographic information. In accordance with the study aims, the analysis of data will identify teachers’ internal and external levels of motivation. The purpose of the qualitative phase is to enhance understanding of teachers’ motivation and of their need for support in the use of physical activity in teaching. Ethics and dissemination All relevant ethics approvals have been acquired. All participants in this study will provide written informed consent prior to data collection. All data emerging from the quantitative and qualitative phase will be anonymised for analysis. Ethics approval was requested from the Regional Committee on Health Research Ethics for Southern Denmark approval ID S-20162000–40 and the Danish Data Protection Agency approval ID 16/15491). The study was deemed not notifiable by both authorities. Trial registration number NCT02894346; Pre-results. PMID:29540419

Combining the power of stories and the power of numbers: mixed methods research and mixed studies reviews.

PubMed

Pluye, Pierre; Hong, Quan Nha

2014-01-01

This article provides an overview of mixed methods research and mixed studies reviews. These two approaches are used to combine the strengths of quantitative and qualitative methods and to compensate for their respective limitations. This article is structured in three main parts. First, the epistemological background for mixed methods will be presented. Afterward, we present the main types of mixed methods research designs and techniques as well as guidance for planning, conducting, and appraising mixed methods research. In the last part, we describe the main types of mixed studies reviews and provide a tool kit and examples. Future research needs to offer guidance for assessing mixed methods research and reporting mixed studies reviews, among other challenges.

Modeling eye gaze patterns in clinician-patient interaction with lag sequential analysis.

PubMed

Montague, Enid; Xu, Jie; Chen, Ping-Yu; Asan, Onur; Barrett, Bruce P; Chewning, Betty

2011-10-01

The aim of this study was to examine whether lag sequential analysis could be used to describe eye gaze orientation between clinicians and patients in the medical encounter. This topic is particularly important as new technologies are implemented into multiuser health care settings in which trust is critical and nonverbal cues are integral to achieving trust. This analysis method could lead to design guidelines for technologies and more effective assessments of interventions. Nonverbal communication patterns are important aspects of clinician-patient interactions and may affect patient outcomes. The eye gaze behaviors of clinicians and patients in 110 videotaped medical encounters were analyzed using the lag sequential method to identify significant behavior sequences. Lag sequential analysis included both event-based lag and time-based lag. Results from event-based lag analysis showed that the patient's gaze followed that of the clinician, whereas the clinician's gaze did not follow the patient's. Time-based sequential analysis showed that responses from the patient usually occurred within 2 s after the initial behavior of the clinician. Our data suggest that the clinician's gaze significantly affects the medical encounter but that the converse is not true. Findings from this research have implications for the design of clinical work systems and modeling interactions. Similar research methods could be used to identify different behavior patterns in clinical settings (physical layout, technology, etc.) to facilitate and evaluate clinical work system designs.

Surface nanobubble nucleation dynamics during water-ethanol exchange

NASA Astrophysics Data System (ADS)

Chan, Chon U.; Ohl, Claus-Dieter

2015-11-01

Water-ethanol exchange has been a promising nucleation method for surface attached nanobubbles since their discovery. In this process, water and ethanol displace each other sequentially on a substrate. As the gas solubility is 36 times higher in ethanol than water, it was suggested that the exchange process leads to transient supersaturation and is responsible for the nanobubble nucleation. In this work, we visualize the nucleation dynamics by controllably mixing water and ethanol. It depicts the temporal evolution of the conventional exchange in a single field of view, detailing the conditions for surface nanobubble nucleation and the flow field that influences their spatial organization. This technique can also pattern surface nanobubbles with variable size distribution.

Computational time analysis of the numerical solution of 3D electrostatic Poisson's equation

NASA Astrophysics Data System (ADS)

Kamboh, Shakeel Ahmed; Labadin, Jane; Rigit, Andrew Ragai Henri; Ling, Tech Chaw; Amur, Khuda Bux; Chaudhary, Muhammad Tayyab

2015-05-01

3D Poisson's equation is solved numerically to simulate the electric potential in a prototype design of electrohydrodynamic (EHD) ion-drag micropump. Finite difference method (FDM) is employed to discretize the governing equation. The system of linear equations resulting from FDM is solved iteratively by using the sequential Jacobi (SJ) and sequential Gauss-Seidel (SGS) methods, simulation results are also compared to examine the difference between the results. The main objective was to analyze the computational time required by both the methods with respect to different grid sizes and parallelize the Jacobi method to reduce the computational time. In common, the SGS method is faster than the SJ method but the data parallelism of Jacobi method may produce good speedup over SGS method. In this study, the feasibility of using parallel Jacobi (PJ) method is attempted in relation to SGS method. MATLAB Parallel/Distributed computing environment is used and a parallel code for SJ method is implemented. It was found that for small grid size the SGS method remains dominant over SJ method and PJ method while for large grid size both the sequential methods may take nearly too much processing time to converge. Yet, the PJ method reduces computational time to some extent for large grid sizes.

A Mixed Methods Sampling Methodology for a Multisite Case Study

ERIC Educational Resources Information Center

Sharp, Julia L.; Mobley, Catherine; Hammond, Cathy; Withington, Cairen; Drew, Sam; Stringfield, Sam; Stipanovic, Natalie

2012-01-01

The flexibility of mixed methods research strategies makes such approaches especially suitable for multisite case studies. Yet the utilization of mixed methods to select sites for these studies is rarely reported. The authors describe their pragmatic mixed methods approach to select a sample for their multisite mixed methods case study of a…

The application of mixed methods designs to trauma research.

PubMed

Creswell, John W; Zhang, Wanqing

2009-12-01

Despite the use of quantitative and qualitative data in trauma research and therapy, mixed methods studies in this field have not been analyzed to help researchers designing investigations. This discussion begins by reviewing four core characteristics of mixed methods research in the social and human sciences. Combining these characteristics, the authors focus on four select mixed methods designs that are applicable in trauma research. These designs are defined and their essential elements noted. Applying these designs to trauma research, a search was conducted to locate mixed methods trauma studies. From this search, one sample study was selected, and its characteristics of mixed methods procedures noted. Finally, drawing on other mixed methods designs available, several follow-up mixed methods studies were described for this sample study, enabling trauma researchers to view design options for applying mixed methods research in trauma investigations.

Satisfaction of patients with directly observed treatment strategy in Addis Ababa, Ethiopia: A mixed-methods study

PubMed Central

Getahun, Belete; Nkosi, Zethu Zerish

2017-01-01

Background Directly observed treatment, short course (DOTS) strategy has been a cornerstone for Tuberculosis (TB) control programs in developing countries. However, in Ethiopia satisfaction level of patients’ with TB with the this strategy is not well understood. Therefore, the study aimed to assess the satisfaction level of patients with TB with the DOTS. Method Explanatory sequential mixed method design was carried out in Addis Ababa, Ethiopia. Interviewer-administered questionnaire with 601 patients with TB who were on follow-up was employed in the quantitative approach. In the qualitative approach telephonic-interview with 25 persons lost to follow-up and focus group discussions with 23 TB experts were conducted. Result Sixty seven percent of respondent was satisfied with the DOTS. Rural residency (AOR = 3.4, 95% CI 1.6, 7.6), having TB symptoms (AOR = 0.6, 95% CI 0.4, 0.94) and treatment supporter (AOR = 4.3, 95%CI 2.7, 6.8) were associated with satisfaction with DOTS. In qualitative finding, all persons lost to follow-up were dissatisfied while TB experts enlightened lack of evidence to affirm the satisfaction level of patients with DOTS. Explored factors contributing to satisfaction include: on time availability of health care providers, DOTS service delivery process, general condition of health care facilities, nutritional support and transportation. Conclusion DOTS is limited to satisfy patients with TB and lacks a consistent system that determines the satisfaction level of patients with TB. Therefore, DOTS strategy needs to have a system to captures patients’ satisfaction level to respond on areas that need progress to improve DOTS service quality. PMID:28182754

Toward Contactless Biology: Acoustophoretic DNA Transfection

NASA Astrophysics Data System (ADS)

Vasileiou, Thomas; Foresti, Daniele; Bayram, Adem; Poulikakos, Dimos; Ferrari, Aldo

2016-02-01

Acoustophoresis revolutionized the field of container-less manipulation of liquids and solids by enabling mixing procedures which avoid contamination and loss of reagents due to the contact with the support. While its applications to chemistry and engineering are straightforward, additional developments are needed to obtain reliable biological protocols in a contactless environment. Here, we provide a first, fundamental step towards biological reactions in air by demonstrating the acoustophoretic DNA transfection of mammalian cells. We developed an original acoustophoretic design capable of levitating, moving and mixing biological suspensions of living mammalians cells and of DNA plasmids. The precise and sequential delivery of the mixed solutions into tissue culture plates is actuated by a novel mechanism based on the controlled actuation of the acoustophoretic force. The viability of the contactless procedure is tested using a cellular model sensitive to small perturbation of neuronal differentiation pathways. Additionally, the efficiency of the transfection procedure is compared to standard, container-based methods for both single and double DNA transfection and for different cell types including adherent growing HeLa cancer cells, and low adhesion neuron-like PC12 cells. In all, this work provides a proof of principle which paves the way to the development of high-throughput acoustophoretic biological reactors.

An Interactive Microsoft(registered tm) Excel Program for Tracking a Single Evaporating Droplet in Crossflow

NASA Technical Reports Server (NTRS)

Liew, K. H.; Urip, E.; Yang, S. L.; Marek, C. J.

2004-01-01

Droplet interaction with a high temperature gaseous crossflow is important because of its wide application in systems involving two phase mixing such as in combustion requiring quick mixing of fuel and air with the reduction of pollutants and for jet mixing in the dilution zone of combustors. Therefore, the focus of this work is to investigate dispersion of a two-dimensional atomized and evaporating spray jet into a two-dimensional crossflow. An interactive Microsoft Excel program for tracking a single droplet in crossflow that has previously been developed will be modified to include droplet evaporation computation. In addition to the high velocity airflow, the injected droplets are also subjected to combustor temperature and pressure that affect their motion in the flow field. Six ordinary differential equations are then solved by 4th-order Runge-Kutta method using Microsoft Excel software. Microsoft Visual Basic programming and Microsoft Excel macrocode are used to produce the data and plot graphs describing the droplet's motion in the flow field. This program computes and plots the data sequentially without forcing the user to open other types of plotting programs. A user's manual on how to use the program is included.

Toward Contactless Biology: Acoustophoretic DNA Transfection.

PubMed

Vasileiou, Thomas; Foresti, Daniele; Bayram, Adem; Poulikakos, Dimos; Ferrari, Aldo

2016-02-01

Acoustophoresis revolutionized the field of container-less manipulation of liquids and solids by enabling mixing procedures which avoid contamination and loss of reagents due to the contact with the support. While its applications to chemistry and engineering are straightforward, additional developments are needed to obtain reliable biological protocols in a contactless environment. Here, we provide a first, fundamental step towards biological reactions in air by demonstrating the acoustophoretic DNA transfection of mammalian cells. We developed an original acoustophoretic design capable of levitating, moving and mixing biological suspensions of living mammalians cells and of DNA plasmids. The precise and sequential delivery of the mixed solutions into tissue culture plates is actuated by a novel mechanism based on the controlled actuation of the acoustophoretic force. The viability of the contactless procedure is tested using a cellular model sensitive to small perturbation of neuronal differentiation pathways. Additionally, the efficiency of the transfection procedure is compared to standard, container-based methods for both single and double DNA transfection and for different cell types including adherent growing HeLa cancer cells, and low adhesion neuron-like PC12 cells. In all, this work provides a proof of principle which paves the way to the development of high-throughput acoustophoretic biological reactors.

Toward Contactless Biology: Acoustophoretic DNA Transfection

PubMed Central

Vasileiou, Thomas; Foresti, Daniele; Bayram, Adem; Poulikakos, Dimos; Ferrari, Aldo

2016-01-01

Acoustophoresis revolutionized the field of container-less manipulation of liquids and solids by enabling mixing procedures which avoid contamination and loss of reagents due to the contact with the support. While its applications to chemistry and engineering are straightforward, additional developments are needed to obtain reliable biological protocols in a contactless environment. Here, we provide a first, fundamental step towards biological reactions in air by demonstrating the acoustophoretic DNA transfection of mammalian cells. We developed an original acoustophoretic design capable of levitating, moving and mixing biological suspensions of living mammalians cells and of DNA plasmids. The precise and sequential delivery of the mixed solutions into tissue culture plates is actuated by a novel mechanism based on the controlled actuation of the acoustophoretic force. The viability of the contactless procedure is tested using a cellular model sensitive to small perturbation of neuronal differentiation pathways. Additionally, the efficiency of the transfection procedure is compared to standard, container-based methods for both single and double DNA transfection and for different cell types including adherent growing HeLa cancer cells, and low adhesion neuron-like PC12 cells. In all, this work provides a proof of principle which paves the way to the development of high-throughput acoustophoretic biological reactors. PMID:26828312

40 CFR 53.34 - Test procedure for methods for PM10 and Class I methods for PM2.5.

Code of Federal Regulations, 2010 CFR

2010-07-01

... simultaneous PM10 or PM2.5 measurements as necessary (see table C-4 of this subpart), each set consisting of...) in appendix A to this subpart). (f) Sequential samplers. For sequential samplers, the sampler shall be configured for the maximum number of sequential samples and shall be set for automatic collection...

Unraveling triadic communication in hospital consultations with adolescents with chronic conditions: the added value of mixed methods research.

PubMed

van Staa, Anneloes

2011-03-01

To integrate findings of a mixed methods research (MMR) into adolescents' preferences and competencies for communication during consultations, in order to demonstrate the added value of MMR for health communication research. Sequential MMR with adolescents (12-19 years) with various chronic conditions in a university hospital. Methods comprised: (1) 31 face-to-face interviews; (2) Q-methodology; (3) 39 observations of outpatient consultations; (4) three focus groups with 27 healthcare providers; (5) web-based questionnaire in 960 adolescents. Adolescents had different preferences regarding health communication, but all wished to be involved as partners. Yet, their actual participation during consultations was low. They often acted as bystanders rather than main characters because their participation was neither requested nor encouraged. Parents filled the gap, to healthcare providers' frustration. The questionnaire confirmed the discrepancy between self-efficacy and self-reported independent behavior during consultations. Triadic communication was all but multi-party-talk and adolescents did not act and were not considered as main partners. MMR was of pivotal importance for our understanding. As chronically ill adolescents need to prepare themselves for transition to adult care, healthcare providers should encourage them to take the lead in communication by initiating independent visits and changing the parents' roles. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Yeast Monitoring of Wine Mixed or Sequential Fermentations Made by Native Strains from D.O. "Vinos de Madrid" Using Real-Time Quantitative PCR.

PubMed

García, Margarita; Esteve-Zarzoso, Braulio; Crespo, Julia; Cabellos, Juan M; Arroyo, Teresa

2017-01-01

There is an increasing trend toward understanding the impact of non- Saccharomyces yeasts on the winemaking process. Although Saccharomyces cerevisiae is the predominant species at the end of fermentation, it has been recognized that the presence of non- Saccharomyces species during alcoholic fermentation can produce an improvement in the quality and complexity of the final wines. A previous work was developed for selecting the best combinations between S. cerevisiae and five non- Saccharomyces ( Torulaspora delbrueckii, Schizosaccharomyces pombe, Candida stellata, Metschnikowia pulcherrima , and Lachancea thermotolorans ) native yeast strains from D.O. "Vinos de Madrid" at the laboratory scale. The best inoculation strategies between S. cerevisiae and non- Saccharomyces strains were chosen to analyze, by real-time quantitative PCR (qPCR) combined with the use of specific primers, the dynamics of inoculated populations throughout the fermentation process at the pilot scale using the Malvar white grape variety. The efficiency of the qPCR system was verified independently of the samples matrix, founding the inoculated yeast species throughout alcoholic fermentation. Finally, we can validate the positive effect of selected co-cultures in the Malvar wine quality, highlighting the sequential cultures of T. delbrueckii CLI 918/ S. cerevisiae CLI 889 and C. stellata CLI 920/ S. cerevisiae CLI 889 and, mixed and sequential cultures of L. thermotolerans 9-6C combined with S. cerevisiae CLI 889.

A mathematical programming approach for sequential clustering of dynamic networks

NASA Astrophysics Data System (ADS)

Silva, Jonathan C.; Bennett, Laura; Papageorgiou, Lazaros G.; Tsoka, Sophia

2016-02-01

A common analysis performed on dynamic networks is community structure detection, a challenging problem that aims to track the temporal evolution of network modules. An emerging area in this field is evolutionary clustering, where the community structure of a network snapshot is identified by taking into account both its current state as well as previous time points. Based on this concept, we have developed a mixed integer non-linear programming (MINLP) model, SeqMod, that sequentially clusters each snapshot of a dynamic network. The modularity metric is used to determine the quality of community structure of the current snapshot and the historical cost is accounted for by optimising the number of node pairs co-clustered at the previous time point that remain so in the current snapshot partition. Our method is tested on social networks of interactions among high school students, college students and members of the Brazilian Congress. We show that, for an adequate parameter setting, our algorithm detects the classes that these students belong more accurately than partitioning each time step individually or by partitioning the aggregated snapshots. Our method also detects drastic discontinuities in interaction patterns across network snapshots. Finally, we present comparative results with similar community detection methods for time-dependent networks from the literature. Overall, we illustrate the applicability of mathematical programming as a flexible, adaptable and systematic approach for these community detection problems. Contribution to the Topical Issue "Temporal Network Theory and Applications", edited by Petter Holme.

Finding False Paths in Sequential Circuits

NASA Astrophysics Data System (ADS)

Matrosova, A. Yu.; Andreeva, V. V.; Chernyshov, S. V.; Rozhkova, S. V.; Kudin, D. V.

2018-02-01

Method of finding false paths in sequential circuits is developed. In contrast with heuristic approaches currently used abroad, the precise method based on applying operations on Reduced Ordered Binary Decision Diagrams (ROBDDs) extracted from the combinational part of a sequential controlling logic circuit is suggested. The method allows finding false paths when transfer sequence length is not more than the given value and obviates the necessity of investigation of combinational circuit equivalents of the given lengths. The possibilities of using of the developed method for more complicated circuits are discussed.

SPMBR: a scalable algorithm for mining sequential patterns based on bitmaps

NASA Astrophysics Data System (ADS)

Xu, Xiwei; Zhang, Changhai

2013-12-01

Now some sequential patterns mining algorithms generate too many candidate sequences, and increase the processing cost of support counting. Therefore, we present an effective and scalable algorithm called SPMBR (Sequential Patterns Mining based on Bitmap Representation) to solve the problem of mining the sequential patterns for large databases. Our method differs from previous related works of mining sequential patterns. The main difference is that the database of sequential patterns is represented by bitmaps, and a simplified bitmap structure is presented firstly. In this paper, First the algorithm generate candidate sequences by SE(Sequence Extension) and IE(Item Extension), and then obtain all frequent sequences by comparing the original bitmap and the extended item bitmap .This method could simplify the problem of mining the sequential patterns and avoid the high processing cost of support counting. Both theories and experiments indicate that the performance of SPMBR is predominant for large transaction databases, the required memory size for storing temporal data is much less during mining process, and all sequential patterns can be mined with feasibility.

Decisional needs assessment of patients with complex care needs in primary care: a participatory systematic mixed studies review protocol

PubMed Central

Pluye, Pierre; Légaré, France; Haggerty, Jeannie; Gore, Genevieve C; Sherif, Reem El; Poitras, Marie-Ève; Beaulieu, Marie-Claude; Beaulieu, Marie-Dominique; Bush, Paula L; Couturier, Yves; Débarges, Béatrice; Gagnon, Justin; Giguère, Anik; Grad, Roland; Granikov, Vera; Goulet, Serge; Hudon, Catherine; Kremer, Bernardo; Kröger, Edeltraut; Kudrina, Irina; Lebouché, Bertrand; Loignon, Christine; Lussier, Marie-Thérèse; Martello, Cristiano; Nguyen, Quynh; Pratt, Rebekah; Rihoux, Benoit; Rosenberg, Ellen; Samson, Isabelle; Senn, Nicolas; Li Tang, David; Tsujimoto, Masashi; Vedel, Isabelle; Ventelou, Bruno; Wensing, Michel; Bigras, Magali

2017-01-01

Introduction Patients with complex care needs (PCCNs) often suffer from combinations of multiple chronic conditions, mental health problems, drug interactions and social vulnerability, which can lead to healthcare services overuse, underuse or misuse. Typically, PCCNs face interactional issues and unmet decisional needs regarding possible options in a cascade of interrelated decisions involving different stakeholders (themselves, their families, their caregivers, their healthcare practitioners). Gaps in knowledge, values clarification and social support in situations where options need to be deliberated hamper effective decision support interventions. This review aims to (1) assess decisional needs of PCCNs from the perspective of stakeholders, (2) build a taxonomy of these decisional needs and (3) prioritise decisional needs with knowledge users (clinicians, patients and managers). Methods and analysis This review will be based on the interprofessional shared decision making (IP-SDM) model and the Ottawa Decision Support Framework. Applying a participatory research approach, we will identify potentially relevant studies through a comprehensive literature search; select relevant ones using eligibility criteria inspired from our previous scoping review on PCCNs; appraise quality using the Mixed Methods Appraisal Tool; conduct a three-step synthesis (sequential exploratory mixed methods design) to build taxonomy of key decisional needs; and integrate these results with those of a parallel PCCNs’ qualitative decisional need assessment (semistructured interviews and focus group with stakeholders). Ethics and dissemination This systematic review, together with the qualitative study (approved by the Centre Intégré Universitaire de Santé et Service Sociaux du Saguenay-Lac-Saint-Jean ethical committee), will produce a working taxonomy of key decisional needs (ontological contribution), to inform the subsequent user-centred design of a support tool for addressing PCCNs’ decisional needs (practical contribution). We will adapt the IP-SDM model, normally dealing with a single decision, for PCCNs who experience cascade of decisions involving different stakeholders (theoretical contribution). Knowledge users will facilitate dissemination of the results in the Canadian primary care network. PROSPERO registration number CRD42015020558. PMID:29133314

Lexical Diversity and Omission Errors as Predictors of Language Ability in the Narratives of Sequential Spanish-English Bilinguals: A Cross-Language Comparison

ERIC Educational Resources Information Center

Jacobson, Peggy F.; Walden, Patrick R.

2013-01-01

Purpose: This study explored the utility of language sample analysis for evaluating language ability in school-age Spanish-English sequential bilingual children. Specifically, the relative potential of lexical diversity and word/morpheme omission as predictors of typical or atypical language status was evaluated. Method: Narrative samples were…

Clinical experiences derived from implementation of an easy to use concept for treatment of wound healing by secondary intention and guidance in selection of appropriate dressings.

PubMed

Braumann, Chris; Guenther, Nina; Menenakos, Charalambos; Muenzberg, Helga; Pirlich, Matthias; Lochs, Herbert; Mueller, Joachim M

2011-06-01

The main objective of this case-cohort-type observational study conducted at different Surgical Departments of the Charité-Universitätsmedizin in Berlin was to evaluate the sequential use concept first described by Systagenix Wound Management in 2007. Fifty-two patients with different wound healing by secondary intention were treated for 7 weeks at the Charité-Universitätsmedizin in Berlin. A multidisciplinary team worked together to reach consensus in wound assessment; in classification of infection status according to the criteria described by European Wound Management Association (EWMA); in treatment protocol and on dressings to be used to 'cover' wounds. Before dressing application, all wounds were cleaned from debris. Following the sequential use concept, wounds classified as stages 2 and 3 were dressed with SILVERCEL(®) and TIELLE(®) or TIELLE PLUS(®) to 'clean' the wounds. After 2-3 weeks, treatment was changed to PROMOGRAN PRISMA(®) and TIELLE(®) to 'close and cover' wounds, thus providing optimal wound healing. Wounds classified as non infected were dressed with PROMOGRAN PRISMA(®) and TIELLE(®) during the complete treatment period. Patients were asked to evaluate the treatment using a simplified questionnaire developed at the Charité-Universitätsmedizin in Berlin. Wounds comprised 37 surgical procedures, 8 chronic mixed ulcer, 4 pressure sores, 1 diabetic foot ulcer, 1 venous leg ulcer, and 1 mixed arterial/venous ulcer. At baseline, 12 wounds were classified as stage 3, 38 wounds as stage 2 and 2 wounds as stage 1. After 7 weeks of treatment, all patients showed a positive clinical response to the sequential use treatment. Results of wound size showed a high significant progression of wound healing expressed with a profound reduction of wound area (P in all measurements <0·001, chi-square test) and improved granulation. This study summarises the clinical experiences derived from the evaluation of the sequential use concept in the daily clinical practice of wound treatment. On the basis of the wound healing results, patients' evaluation of treatment and the clinicians' and staff experiences, this concept was implemented at different Surgical Departments of the Charité-Universitätsmedizin in Berlin. © 2011 The Authors. © 2011 Blackwell Publishing Ltd and Medicalhelplines.com Inc.

Employing natural reagents from turmeric and lime for acetic acid determination in vinegar sample.

PubMed

Supharoek, Sam-Ang; Ponhong, Kraingkrai; Siriangkhawut, Watsaka; Grudpan, Kate

2018-04-01

A simple, rapid and environmentally friendly sequential injection analysis system employing natural extract reagents was developed for the determination of acetic acid following an acid-base reaction in the presence of an indicator. Powdered lime and turmeric were utilized as the natural base and indicator, respectively. Mixing lime and turmeric produced an orange to reddish-brown color solution which absorbed the maximum wavelength at 455 nm, with absorbance decreasing with increasing acetic acid concentration. Influential parameters including lime and turmeric concentrations, reagent and sample aspirated volumes, mixing coil length and dispensing flow rate were investigated and optimized. A standard calibration graph was plotted for 0-5.0 mmol/L acetic acid with r 2  = 0.9925. Relative standard deviations (RSD) at 2.0 and 4.0 mmol/L acetic acid were less than 3% (n = 7), with limit of detection (LOD) and limit of quantification (LOQ) at 0.12 and 0.24 mmol/L, respectively. The method was successfully applied to assay acetic acid concentration in cooking vinegar samples. Results achieved were not significantly different from those obtained following a batchwise standard AOAC titration method. Copyright © 2017. Published by Elsevier B.V.

Prevalence of Mixed-Methods Sampling Designs in Social Science Research

ERIC Educational Resources Information Center

Collins, Kathleen M. T.

2006-01-01

The purpose of this mixed-methods study was to document the prevalence of sampling designs utilised in mixed-methods research and to examine the interpretive consistency between interpretations made in mixed-methods studies and the sampling design used. Classification of studies was based on a two-dimensional mixed-methods sampling model. This…

Acceptability and Feasibility of a Shared Decision-Making Model in Work Rehabilitation: A Mixed-Methods Study of Stakeholders' Perspectives.

PubMed

Coutu, Marie-France; Légaré, France; Durand, Marie-José; Stacey, Dawn; Labrecque, Marie-Elise; Corbière, Marc; Bainbridge, Lesley

2018-04-16

Purpose To establish the acceptability and feasibility of implementing a shared decision-making (SDM) model in work rehabilitation. Methods We used a sequential mixed-methods design with diverse stakeholder groups (representatives of private and public employers, insurers, and unions, as well as workers having participated in a work rehabilitation program). First, a survey using a self-administered questionnaire enabled stakeholders to rate their level of agreement with the model's acceptability and feasibility and propose modifications, if necessary. Second, eight focus groups representing key stakeholders (n = 34) and four one-on-one interviews with workers were conducted, based on the questionnaire results. For each stakeholder group, we computed the percentage of agreement with the model's acceptability and feasibility and performed thematic analyses of the transcripts. Results Less than 50% of each stakeholder group initially agreed with the overall acceptability and feasibility of the model. Stakeholders proposed 37 modifications to the objectives, 17 to the activities, and 39 to improve the model's feasibility. Based on in-depth analysis of the transcripts, indicators were added to one objective, an interview guide was added as proposed by insurers to ensure compliance of the SDM process with insurance contract requirements, and one objective was reformulated. Conclusion Despite initially low agreement with the model's acceptability on the survey, subsequent discussions led to three minor changes and contributed to the model's ultimate acceptability and feasibility. Later steps will involve assessing the extent of implementation of the model in real rehabilitation settings to see if other modifications are necessary before assessing its impact.

Multi-point objective-oriented sequential sampling strategy for constrained robust design

NASA Astrophysics Data System (ADS)

Zhu, Ping; Zhang, Siliang; Chen, Wei

2015-03-01

Metamodelling techniques are widely used to approximate system responses of expensive simulation models. In association with the use of metamodels, objective-oriented sequential sampling methods have been demonstrated to be effective in balancing the need for searching an optimal solution versus reducing the metamodelling uncertainty. However, existing infilling criteria are developed for deterministic problems and restricted to one sampling point in one iteration. To exploit the use of multiple samples and identify the true robust solution in fewer iterations, a multi-point objective-oriented sequential sampling strategy is proposed for constrained robust design problems. In this article, earlier development of objective-oriented sequential sampling strategy for unconstrained robust design is first extended to constrained problems. Next, a double-loop multi-point sequential sampling strategy is developed. The proposed methods are validated using two mathematical examples followed by a highly nonlinear automotive crashworthiness design example. The results show that the proposed method can mitigate the effect of both metamodelling uncertainty and design uncertainty, and identify the robust design solution more efficiently than the single-point sequential sampling approach.

Simultaneous co-fermentation of mixed sugars: a promising strategy for producing cellulosic ethanol.

PubMed

Kim, Soo Rin; Ha, Suk-Jin; Wei, Na; Oh, Eun Joong; Jin, Yong-Su

2012-05-01

The lack of microbial strains capable of fermenting all sugars prevalent in plant cell wall hydrolyzates to ethanol is a major challenge. Although naturally existing or engineered microorganisms can ferment mixed sugars (glucose, xylose and galactose) in these hydrolyzates sequentially, the preferential utilization of glucose to non-glucose sugars often results in lower overall yield and productivity of ethanol. Therefore, numerous metabolic engineering approaches have been attempted to construct optimal microorganisms capable of co-fermenting mixed sugars simultaneously. Here, we present recent findings and breakthroughs in engineering yeast for improved ethanol production from mixed sugars. In particular, this review discusses new sugar transporters, various strategies for simultaneous co-fermentation of mixed sugars, and potential applications of co-fermentation for producing fuels and chemicals. Copyright © 2012 Elsevier Ltd. All rights reserved.

Assessment of cognitive bias in decision-making and leadership styles among critical care nurses: a mixed methods study.

PubMed

Lean Keng, Soon; AlQudah, Hani Nawaf Ibrahim

2017-02-01

To raise awareness of critical care nurses' cognitive bias in decision-making, its relationship with leadership styles and its impact on care delivery. The relationship between critical care nurses' decision-making and leadership styles in hospitals has been widely studied, but the influence of cognitive bias on decision-making and leadership styles in critical care environments remains poorly understood, particularly in Jordan. Two-phase mixed methods sequential explanatory design and grounded theory. critical care unit, Prince Hamza Hospital, Jordan. Participant sampling: convenience sampling Phase 1 (quantitative, n = 96), purposive sampling Phase 2 (qualitative, n = 20). Pilot tested quantitative survey of 96 critical care nurses in 2012. Qualitative in-depth interviews, informed by quantitative results, with 20 critical care nurses in 2013. Descriptive and simple linear regression quantitative data analyses. Thematic (constant comparative) qualitative data analysis. Quantitative - correlations found between rationality and cognitive bias, rationality and task-oriented leadership styles, cognitive bias and democratic communication styles and cognitive bias and task-oriented leadership styles. Qualitative - 'being competent', 'organizational structures', 'feeling self-confident' and 'being supported' in the work environment identified as key factors influencing critical care nurses' cognitive bias in decision-making and leadership styles. Two-way impact (strengthening and weakening) of cognitive bias in decision-making and leadership styles on critical care nurses' practice performance. There is a need to heighten critical care nurses' consciousness of cognitive bias in decision-making and leadership styles and its impact and to develop organization-level strategies to increase non-biased decision-making. © 2016 John Wiley & Sons Ltd.

Limitation of duty hour regulations for pediatric resident wellness: A mixed methods study in Japan.

PubMed

Nomura, Osamu; Mishina, Hiroki; Kobayashi, Yoshinori; Ishiguro, Akira; Sakai, Hirokazu; Kato, Hiroyuki

2016-09-01

Duty hour regulations have been placed in residency programs to address mental health concerns and to improve wellness. Here, we elucidate the prevalence of depressive symptoms after implementing an overnight call shift system and the factors associated with burnout or depression among residents.A sequential exploratory mixed methods study was conducted in a tertiary care pediatric and perinatal hospital in Tokyo, Japan. A total of 41 pediatric residents participated in the cross-sectional survey. We determined and compared the prevalence of depressive symptoms and the number of actual working hours before and after implementing the shift system. A follow-up focus-group interview with 4 residents was conducted to explore the factors that may trigger or prevent depression and burnout.Mean working hours significantly decreased from 75.2 hours to 64.9 hours per week. Prevalence of depressive symptoms remained similar before and after implementation of the shift system. Emotional exhaustion and depersonalization from the burnout scale were markedly associated with depression. High workload, stress intolerance, interpersonal difficulties, and generation gaps regarding work-life balance could cause burnout. Stress tolerance, workload monitoring and balancing, appropriate supervision, and peer support could prevent burnout.Although the overnight call shift system was effective in reducing working hours, its effectiveness in managing mental health issues among pediatric residents remains unclear. Resident wellness programs represent an additional strategy and they should be aimed at fostering peer support and improvement of resident-faculty interactions. Such an approach could be beneficial to the relationship between physicians of different generations with conflicting belief structures.

The role, practice and training of unregulated birth workers in Australia: A mixed methods study.

PubMed

Rigg, Elizabeth C; Schmied, Virginia; Peters, Kath; Dahlen, Hannah G

2018-05-23

In Australia, the provision of homebirth services by unregulated birthworkers (doulas, ex-registered midwives, traditional midwives and lay workers) has increased. Accessing a homebirth with a registered midwife via mainstream services is limited. Concern is growing that new legislation aimed at prohibiting unregulated birthworkers practice may result in homebirth going underground. To explore the role, practice and training of unregulated birthworkers in Australian and establish what they would do if legislation prohibited their practice. This study used a mixed methods sequential exploratory design to explore the practice, training and role of unregulated birthworkers in Australia. In phase one, four unregulated birthworkers were interviewed in-depth and the findings informed the development of a survey in phase two. This was distributed nationally through two consumer websites, social media, Facebook and email. Data from both phases were integrated. Unregulated birthworkers in Australia provide homebirth services to women with high and low-risk pregnancies when this choice is unavailable or unacceptable within mainstream services. They operate covertly to protect their practice and avoid the scrutiny of authorities. Unregulated birthworkers can be experienced and trained in childbirth care and practice, much like a midwife working within a holistic paradigm of care. Unregulated birthworkers believe they provide women with the homebirth service they want but cannot access. Mainstream service providers need to listen to consumer criticisms, as women seek answers outside the system. Change is needed to improve and align services with women's expectations of homebirth. Copyright © 2018 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.

Exploring new graduate nurse confidence in interprofessional collaboration: a mixed methods study.

PubMed

Pfaff, Kathryn A; Baxter, Pamela E; Jack, Susan M; Ploeg, Jenny

2014-08-01

Confidence is required for effective engagement in interprofessional collaboration. New graduate nurses often lack confidence in interprofessional interactions, and this may compromise the delivery of safe and effective healthcare. The overall objective of this study was to explore new graduate nurse confidence in interprofessional collaboration. An explanatory sequential mixed methods design was used. New graduate nurses from Ontario, Canada (N=514) completed a cross-sectional descriptive survey in 2012. The survey measured perceived confidence in interprofessional collaboration, and it included items that were proposed to have a relationship with new graduate nurse confidence in interprofessional collaboration. Follow-up qualitative telephone interviews were conducted with 16 new graduate nurses. The quantitative findings suggested that several factors have a positive relationship with new graduate nurse confidence in interprofessional collaboration: availability and accessibility of manager, availability and accessibility of educator, number of different disciplines worked with daily, number of team strategies, and satisfaction with team. The qualitative phase supported the quantitative findings and also provided new information about factors that facilitated and challenged new graduate nurse confidence when engaging in interprofessional collaboration. The facilitators were: experience, knowledge, respect, supportive relationships, and opportunities to collaborate. Challenges included: lack of experience, lack of knowledge, communication challenges, and balancing practice expectations. The overall findings relate to team and organizational support, and new graduate nurse development. Interventions that provide support for interprofessional collaboration at the team and organizational levels, and develop new graduate nurse knowledge and experiences regarding collaborative practice, are essential for enhancing new graduate nurse confidence in interprofessional collaboration. Copyright © 2014 Elsevier Ltd. All rights reserved.

Developing a Web Platform to Support a Community of Practice: A Mixed Methods Study in Pediatric Physiotherapy.

PubMed

Pratte, Gabrielle; Hurtubise, Karen; Rivard, Lisa; Berbari, Jade; Camden, Chantal

2018-01-01

Web platforms are increasingly used to support virtual interactions between members of communities of practice (CoP). However, little is known about how to develop these platforms to support the implementation of best practices for health care professionals. The aim of this article is to explore pediatric physiotherapists' (PTs) perspectives regarding the utility and usability of the characteristic of a web platform developed to support virtual communities of practice (vCoP). This study adopted an explanatory sequential mixed methods design. A web platform supporting the interactions of vCoP members was developed for PTs working with children with developmental coordination disorder. Specific strategies and features were created to support the effectiveness of the platform across three domains: social, information-quality, and system-quality factors. Quantitative data were collected from a cross-sectional survey (n = 41) after 5 months of access to the web platform. Descriptive statistics were calculated. Qualitative data were also collected from semistructured interviews (n = 9), which were coded, interpreted, and analyzed by using Boucher's Web Ergonomics Conceptual Framework. The utility of web platform characteristics targeting the three key domain factors were generally perceived positively by PTs. However, web platform usability issues were noted by PTs, including problems with navigation and information retrieval. Web platform aiming to support vCoP should be carefully developed to target potential users' needs. Whenever possible, users should co-construct the web platform with vCoP developers. Moreover, each of the developed characteristics (eg, newsletter, search function) should be evaluated in terms of utility and usability for the users.

Preparedness of Health Care Professionals for Delivering Sexual and Reproductive Health Care to Refugee and Migrant Women: A Mixed Methods Study.

PubMed

Mengesha, Zelalem B; Perz, Janette; Dune, Tinashe; Ussher, Jane

2018-01-22

Past research suggests that factors related to health care professionals' (HCPs) knowledge, training and competency can contribute to the underutilisation of sexual and reproductive health (SRH) care by refugee and migrant women. The aim of this study was to examine the perceived preparedness of HCPs in relation to their knowledge, confidence and training needs when it comes to consulting refugee and migrant women seeking SRH care in Australia. A sequential mixed methods design, comprising an online survey with 79 HCPs (45.6% nurses, 30.3% general practitioners (GPs), 16.5% health promotion officers, and 7.6% allied health professionals) and semi-structured interviews with 21 HCPs, was utilised. HCPs recognised refugee and migrant women's SRH as a complex issue that requires unique skills for the delivery of optimal care. However, they reported a lack of training (59.4% of nurses, 50% of GPs, and 38.6% of health promotion officers) and knowledge (27.8% of nurses, 20.8% of GPs, and 30.8% of health promotion officers) in addressing refugee and migrant women's SRH. The majority of participants (88.9% of nurses, 75% of GPs, and 76% of health promotion officers) demonstrated willingness to engage with further training in refugee and migrant women's SRH. The implications of the findings are argued regarding the need to train HCPs in culturally sensitive care and include the SRH of refugee and migrant women in university and professional development curricula in meeting the needs of this growing and vulnerable group of women.

Is psychotherapy for functional somatic syndromes harmful? A mixed methods study on negative effects.

PubMed

Holsting, A F; Pedersen, H F; Rask, M T; Frostholm, L; Schröder, A

2017-07-01

Concern for negative effects of psychotherapy for functional somatic syndromes (FSS) has been expressed by clinicians and some patient associations, which may prevent patients from seeking treatment. Therefore, we sought to explore the occurrence and characteristics of negative effects from group-based psychotherapy as experienced by patients with severe or multiple FSS. An adapted version of the explanatory sequential mixed methods design was applied. We used data from an on-going pilot study on Acceptance and Commitment Therapy and Mindfulness-Based Stress Reduction. Negative effects were measured by Inventory for the assessment of Negative Effects of Psychotherapy (INEP). In addition, telephone interviews were conducted with randomly chosen patients and patients who reported negative effects. The latter were asked to elaborate on their INEP response. Quantitative data were analysed descriptively while interview transcripts were explored by thematic analysis. Eighty patients responded to the questionnaire (89%). Negative effects to different extent (from 'slightly agree' to 'fully agree') were reported by 25 (31%). The most frequent negative effects were dependence on the therapist (12%), feeling down after therapy (6%) and insurance problems (7%). By exploring 27 participants' experiences of negative effects 3 main themes were identified: relations in therapy, outcome and transition from therapy to everyday life. Patients with FSS reported a few specific negative effects, all with low frequency. Generally, therapy was well-received. Some patients did however express negative effects both within and outside the therapeutic context. It is important to inform patients about potential negative effects prior to psychotherapy. Copyright © 2017 Elsevier Inc. All rights reserved.

Why did I become a nurse? Personality traits and reasons for entering nursing.

PubMed

Eley, Diann; Eley, Rob; Bertello, Marisa; Rogers-Clark, Cath

2012-07-01

This article is a report of a mixed method study of the association between personality traits of nurses and their reasons for entering nursing. Background.  The worldwide nursing shortage prompts research into better understanding of why individuals enter nursing and may assist in exploring ways to increase their recruitment and long term retention. A mixed method sequential explanatory design employed semi-structured interviews and a validated personality inventory measuring temperament and character traits. Registered Nurses (n = 12) and nursing students (n = 11) working and studying in a regional area of Queensland Australia were purposively sampled for the interviews in 2010 from their participation in the survey in 2009 investigating their personality traits. Qualitative data collection stopped at saturation. A thematic content analysis of the qualitative data using the framework approach was interpreted alongside their personality trait profiles. Two dominant themes were identified from the participant interviews about reasons for entering nursing; 'opportunity for caring' and 'my vocation in life'. These themes were congruent with key temperament and character traits measured in the participants. All nurses and students were very high in traits that exude empathy and altruistic ideals regardless of other characteristics which included highly pragmatic and self-serving principles. Qualitative and quantitative findings suggest that a caring nature is a principal quality of the nursing personality. Recruitment and retention strategies whilst promoting multiple benefits for the profession should not forget that the prime impetus for entering nursing is the opportunity to care for others. © 2012 Blackwell Publishing Ltd.

‘Talkin’ ‘Bout My Generation’: Using a Mixed-Methods Approach to Explore Changes in Adolescent Well-Being across Several European Countries

PubMed Central

Cosma, Alina; Belić, Jelisaveta; Blecha, Ondřej; Fenski, Friederike; Lo, Man Y.; Murár, Filip; Petrovic, Darija; Stella, Maria T.

2017-01-01

The promotion of positive mental health is a becoming priority worldwide. Despite all the efforts invested in preventive and curative work, it is estimated that one in four persons will experience a mental health condition at some point in their lives. Even more worrying is the fact that up to a half of all mental health problems have their onset before the age of 14. Recent statistics (national and international surveys, meta-analyses, international reports) point out to the fact that child and adolescent mental health problems are on the rise. The present study will try to corroborate these results and further explore their meaning, by employing a sequential mixed methods research design (quantitative–qualitative). The quantitative part will analyze time trends using Health Behaviors in School-aged Children data (four survey cycles: 2002, 2006, 2010, 2014) on mental well-being from four European countries (the Czechia, Germany, Italy, and United Kingdom). The qualitative part will rely on focus groups to explore the perspectives of 13- and 15-year-old boys and girls on gender differences and on the changes in adolescent mental well-being over time, as well as measures through which these issues could be addressed. Thematic analysis will be employed to analyze qualitative data. The results of this study could make a major contribution to our understanding of the current trends in adolescent mental well-being, as well as the ways in which existing data could be linked to international and national health policies. PMID:28572776

Development of a resilience scale for Thai substance-dependent women: A mixed methods approach.

PubMed

Sakunpong, Nanchatsan; Choochom, Oraphin; Taephant, Nattasuda

2016-08-01

The purpose of this study was to develop a resilience scale based on the experiences of substance-dependent women in Thailand and evaluate its validity and reliability. A sequential exploratory mixed methods design was employed as the main methodology to develop the resilience scale according to the results from qualitative data by analyzing focus group discussions of 13 participants. Then, the scale was administered to 252 substance-dependent women from four substance-treatment centers. The psychometric properties were explored with an index of item objective congruence (IOC), Pearson correlation, second-order confirmatory factor analysis and Cronbach's alpha coefficient to estimate the quantitative data. The qualitative results showed that resilience is defined by three themes: individual, family and community factors, consisted of 13 different categories. The quantitative results also revealed that all 71 items in the resilience scale passed the IOC criteria, convergence and construct validity. The goodness-of-fit indices demonstrated that the resilience model was consistent with the empirical data. (Chi-square=74.28, df=59, p-value=0.08, RMSEA=0.03, SRMR=0.04, NNFI=0.99, CFI=0.99, GFI=0.96). The internal consistency, assessed by a Cronbach's alpha score of 0.92, can be interpreted as demonstrating high reliability. Furthermore, the structure of the resilience scale was confirmed by the available resilience literature. This study can help clinicians gain a more comprehensive understanding regarding the complex process of resilience among substance-dependent women and aid them in providing these women with the appropriate interventions. Copyright © 2015 Elsevier B.V. All rights reserved.

High-resolution Observations of Flares in an Arch Filament System

NASA Astrophysics Data System (ADS)

Su, Yingna; Liu, Rui; Li, Shangwei; Cao, Wenda; Ahn, Kwangsu; Ji, Haisheng

2018-03-01

We study five sequential solar flares (SOL2015-08-07) occurring in Active Region 12396 observed with the Goode Solar Telescope (GST) at the Big Bear Solar Observatory, complemented by Interface Region Imaging Spectrograph and SDO observations. The main flaring region is an arch filament system (AFS) consisting of multiple bundles of dark filament threads enclosed by semicircular flare ribbons. We study the magnetic configuration and evolution of the active region by constructing coronal magnetic field models based on SDO/HMI magnetograms using two independent methods, i.e., the nonlinear force-free field (NLFFF) extrapolation and the flux rope insertion method. The models consist of multiple flux ropes with mixed signs of helicity, i.e., positive (negative) in the northern (southern) region, which is consistent with the GST observations of multiple filament bundles. The footprints of quasi-separatrix layers (QSLs) derived from the extrapolated NLFFF compare favorably with the observed flare ribbons. An interesting double-ribbon fine structure located at the east border of the AFS is consistent with the fine structure of the QSL’s footprint. Moreover, magnetic field lines traced along the semicircular footprint of a dome-like QSL surrounding the AFS are connected to the regions of significant helicity and Poynting flux injection. The maps of magnetic twist show that positive twist became dominant as time progressed, which is consistent with the injection of positive helicity before the flares. We hence conclude that these circular shaped flares are caused by 3D magnetic reconnection at the QSLs associated with the AFS possessing mixed signs of helicity.

Preparedness of Health Care Professionals for Delivering Sexual and Reproductive Health Care to Refugee and Migrant Women: A Mixed Methods Study

PubMed Central

Mengesha, Zelalem B.; Perz, Janette; Dune, Tinashe; Ussher, Jane

2018-01-01

Past research suggests that factors related to health care professionals’ (HCPs) knowledge, training and competency can contribute to the underutilisation of sexual and reproductive health (SRH) care by refugee and migrant women. The aim of this study was to examine the perceived preparedness of HCPs in relation to their knowledge, confidence and training needs when it comes to consulting refugee and migrant women seeking SRH care in Australia. A sequential mixed methods design, comprising an online survey with 79 HCPs (45.6% nurses, 30.3% general practitioners (GPs), 16.5% health promotion officers, and 7.6% allied health professionals) and semi-structured interviews with 21 HCPs, was utilised. HCPs recognised refugee and migrant women’s SRH as a complex issue that requires unique skills for the delivery of optimal care. However, they reported a lack of training (59.4% of nurses, 50% of GPs, and 38.6% of health promotion officers) and knowledge (27.8% of nurses, 20.8% of GPs, and 30.8% of health promotion officers) in addressing refugee and migrant women’s SRH. The majority of participants (88.9% of nurses, 75% of GPs, and 76% of health promotion officers) demonstrated willingness to engage with further training in refugee and migrant women’s SRH. The implications of the findings are argued regarding the need to train HCPs in culturally sensitive care and include the SRH of refugee and migrant women in university and professional development curricula in meeting the needs of this growing and vulnerable group of women. PMID:29361799

Variation in fistula use across dialysis facilities: is it explained by case-mix?

PubMed

Tangri, Navdeep; Moorthi, Ranjani; Tighiouhart, Hocine; Meyer, Klemens B; Miskulin, Dana C

2010-02-01

Arteriovenous fistulas (AVFs) remain the preferred vascular access for hemodialysis patients. Dialysis facilities that fail to meet Centers for Medicare & Medicaid Services goals cite patient case-mix as a reason for low AVF prevalence. This study aimed to determine the magnitude of the variability in AVF usage across dialysis facilities and the extent to which patient case-mix explains it. The vascular access used in 10,112 patients dialyzed at 173 Dialysis Clinic Inc. facilities from October 1 to December 31, 2004, was evaluated. The access in use was considered to be an AVF if it was used for >70% of hemodialysis treatments. Mixed-effects models with a random intercept for dialysis facilities evaluated the effect of facilities on AVF usage. Sequentially adjusted multivariate models measured the extent to which patient factors (case-mix) explain variation across facilities in AVF rates. 3787 patients (38%) were dialyzed using AVFs. There was a significant facility effect: 7.6% of variation in AVF use was attributable to facility. This was reduced to 7.1% after case-mix adjustment. There were no identified specific facility-level factors that explained the interfacility variation. AVF usage varies across dialysis facilities, and patient case-mix did not reduce this variation. In this study, 92% of the total variation in AVF usage was due to patient factors, but most were not measurable. A combination of patient factors and process indicators should be considered in adjudicating facility performance for this quality indicator.

On the mixing and evaporation of secondary organic aerosol components.

PubMed

Loza, Christine L; Coggon, Matthew M; Nguyen, Tran B; Zuend, Andreas; Flagan, Richard C; Seinfeld, John H

2013-06-18

The physical state and chemical composition of an organic aerosol affect its degree of mixing and its interactions with condensing species. We present here a laboratory chamber procedure for studying the effect of the mixing of organic aerosol components on particle evaporation. The procedure is applied to the formation of secondary organic aerosol (SOA) from α-pinene and toluene photooxidation. SOA evaporation is induced by heating the chamber aerosol from room temperature (25 °C) to 42 °C over 7 h and detected by a shift in the peak diameter of the SOA size distribution. With this protocol, α-pinene SOA is found to be more volatile than toluene SOA. When SOA is formed from the two precursors sequentially, the evaporation behavior of the SOA most closely resembles that of SOA from the second parent hydrocarbon, suggesting that the structure of the mixed SOA resembles a core of SOA from the initial precursor coated by a layer of SOA from the second precursor. Such a core-and-shell configuration of the organic aerosol phases implies limited mixing of the SOA from the two precursors on the time scale of the experiments, consistent with a high viscosity of at least one of the phases.

Techniques for Estimating Emissions Factors from Forest Burning: ARCTAS and SEAC4RS Airborne Measurements Indicate which Fires Produce Ozone

NASA Technical Reports Server (NTRS)

Chatfield, Robert B.; Andreae, Meinrat O.

2016-01-01

Previous studies of emission factors from biomass burning are prone to large errors since they ignore the interplay of mixing and varying pre-fire background CO2 levels. Such complications severely affected our studies of 446 forest fire plume samples measured in the Western US by the science teams of NASA's SEAC4RS and ARCTAS airborne missions. Consequently we propose a Mixed Effects Regression Emission Technique (MERET) to check techniques like the Normalized Emission Ratio Method (NERM), where use of sequential observations cannot disentangle emissions and mixing. We also evaluate a simpler "consensus" technique. All techniques relate emissions to fuel burned using C(burn) = delta C(tot) added to the fire plume, where C(tot) approximately equals (CO2 = CO). Mixed-effects regression can estimate pre-fire background values of C(tot) (indexed by observation j) simultaneously with emissions factors indexed by individual species i, delta, epsilon lambda tau alpha-x(sub I)/C(sub burn))I,j. MERET and "consensus" require more than emissions indicators. Our studies excluded samples where exogenous CO or CH4 might have been fed into a fire plume, mimicking emission. We sought to let the data on 13 gases and particulate properties suggest clusters of variables and plume types, using non-negative matrix factorization (NMF). While samples were mixtures, the NMF unmixing suggested purer burn types. Particulate properties (b scant, b abs, SSA, AAE) and gas-phase emissions were interrelated. Finally, we sought a simple categorization useful for modeling ozone production in plumes. Two kinds of fires produced high ozone: those with large fuel nitrogen as evidenced by remnant CH3CN in the plumes, and also those from very intense large burns. Fire types with optimal ratios of delta-NOy/delta- HCHO associate with the highest additional ozone per unit Cburn, Perhaps these plumes exhibit limited NOx binding to reactive organics. Perhaps these plumes exhibit limited NOx binding to reactive organics