Concerns, Considerations, and New Ideas for Data Collection and Research in Educational Technology Studies

ERIC Educational Resources Information Center

Bebell, Damian; O'Dwyer, Laura M.; Russell, Michael; Hoffmann, Tom

2010-01-01

In the following pages, we examine some common methodological challenges in educational technology research and highlight new data collection approaches using examples from the literature and our own work. Given that surveys and questionnaires remain widespread and dominant tools across nearly all studies of educational technology, we first…

Equity Analytics: A Methodological Approach for Quantifying Participation Patterns in Mathematics Classroom Discourse

ERIC Educational Resources Information Center

Reinholz, Daniel L.; Shah, Niral

2018-01-01

Equity in mathematics classroom discourse is a pressing concern, but analyzing issues of equity using observational tools remains a challenge. In this article, we propose equity analytics as a quantitative approach to analyzing aspects of equity and inequity in classrooms. We introduce a classroom observation tool that focuses on relatively…

Toward a Digital Thread and Data Package for Metals-Additive Manufacturing.

PubMed

Kim, D B; Witherell, P; Lu, Y; Feng, S

2017-01-01

Additive manufacturing (AM) has been envisioned by many as a driving factor of the next industrial revolution. Potential benefits of AM adoption include the production of low-volume, customized, complicated parts/products, supply chain efficiencies, shortened time-to-market, and environmental sustainability. Work remains, however, for AM to reach the status of a full production-ready technology. Whereas the ability to create unique 3D geometries has been generally proven, production challenges remain, including lack of (1) data manageability through information management systems, (2) traceability to promote product producibility, process repeatability, and part-to-part reproducibility, and (3) accountability through mature certification and qualification methodologies. To address these challenges in part, this paper discusses the building of data models to support the development of validation and conformance methodologies in AM. We present an AM information map that leverages informatics to facilitate part producibility, process repeatability, and part-to-part reproducibility in an AM process. We present three separate case studies to demonstrate the importance of establishing baseline data structures and part provenance through an AM digital thread.

Toward a Digital Thread and Data Package for Metals-Additive Manufacturing

PubMed Central

Kim, D. B.; Witherell, P.; Lu, Y.; Feng, S.

2017-01-01

Additive manufacturing (AM) has been envisioned by many as a driving factor of the next industrial revolution. Potential benefits of AM adoption include the production of low-volume, customized, complicated parts/products, supply chain efficiencies, shortened time-to-market, and environmental sustainability. Work remains, however, for AM to reach the status of a full production-ready technology. Whereas the ability to create unique 3D geometries has been generally proven, production challenges remain, including lack of (1) data manageability through information management systems, (2) traceability to promote product producibility, process repeatability, and part-to-part reproducibility, and (3) accountability through mature certification and qualification methodologies. To address these challenges in part, this paper discusses the building of data models to support the development of validation and conformance methodologies in AM. We present an AM information map that leverages informatics to facilitate part producibility, process repeatability, and part-to-part reproducibility in an AM process. We present three separate case studies to demonstrate the importance of establishing baseline data structures and part provenance through an AM digital thread. PMID:28691115

Fracture Mechanics for Composites: State of the Art and Challenges

NASA Technical Reports Server (NTRS)

Krueger, Ronald; Krueger, Ronald

2006-01-01

Interlaminar fracture mechanics has proven useful for characterizing the onset of delaminations in composites and has been used with limited success primarily to investigate onset in fracture toughness specimens and laboratory size coupon type specimens. Future acceptance of the methodology by industry and certification authorities however, requires the successful demonstration of the methodology on the structural level. In this paper, the state-of-the-art in fracture toughness characterization, and interlaminar fracture mechanics analysis tools are described. To demonstrate the application on the structural level, a panel was selected which is reinforced with stringers. Full implementation of interlaminar fracture mechanics in design however remains a challenge and requires a continuing development effort of codes to calculate energy release rates and advancements in delamination onset and growth criteria under mixed mode conditions.

Conducting a meta-ethnography of qualitative literature: lessons learnt.

PubMed

Atkins, Salla; Lewin, Simon; Smith, Helen; Engel, Mark; Fretheim, Atle; Volmink, Jimmy

2008-04-16

Qualitative synthesis has become more commonplace in recent years. Meta-ethnography is one of several methods for synthesising qualitative research and is being used increasingly within health care research. However, many aspects of the steps in the process remain ill-defined. We utilized the seven stages of the synthesis process to synthesise qualitative research on adherence to tuberculosis treatment. In this paper we discuss the methodological and practical challenges faced; of particular note are the methods used in our synthesis, the additional steps that we found useful in clarifying the process, and the key methodological challenges encountered in implementing the meta-ethnographic approach. The challenges included shaping an appropriate question for the synthesis; identifying relevant studies; assessing the quality of the studies; and synthesising findings across a very large number of primary studies from different contexts and research traditions. We offer suggestions that may assist in undertaking meta-ethnographies in the future. Meta-ethnography is a useful method for synthesising qualitative research and for developing models that interpret findings across multiple studies. Despite its growing use in health research, further research is needed to address the wide range of methodological and epistemological questions raised by the approach.

Conducting a meta-ethnography of qualitative literature: Lessons learnt

PubMed Central

Atkins, Salla; Lewin, Simon; Smith, Helen; Engel, Mark; Fretheim, Atle; Volmink, Jimmy

2008-01-01

Background Qualitative synthesis has become more commonplace in recent years. Meta-ethnography is one of several methods for synthesising qualitative research and is being used increasingly within health care research. However, many aspects of the steps in the process remain ill-defined. Discussion We utilized the seven stages of the synthesis process to synthesise qualitative research on adherence to tuberculosis treatment. In this paper we discuss the methodological and practical challenges faced; of particular note are the methods used in our synthesis, the additional steps that we found useful in clarifying the process, and the key methodological challenges encountered in implementing the meta-ethnographic approach. The challenges included shaping an appropriate question for the synthesis; identifying relevant studies; assessing the quality of the studies; and synthesising findings across a very large number of primary studies from different contexts and research traditions. We offer suggestions that may assist in undertaking meta-ethnographies in the future. Summary Meta-ethnography is a useful method for synthesising qualitative research and for developing models that interpret findings across multiple studies. Despite its growing use in health research, further research is needed to address the wide range of methodological and epistemological questions raised by the approach. PMID:18416812

Helicopter-V/STOL dynamic wind and turbulence design methodology

NASA Technical Reports Server (NTRS)

Bailey, J. Earl

1987-01-01

Aircraft and helicopter accidents due to severe dynamic wind and turbulence continue to present challenging design problems. The development of the current set of design analysis tools for a aircraft wind and turbulence design began in the 1940's and 1950's. The areas of helicopter dynamic wind and turbulence modeling and vehicle response to severe dynamic wind inputs (microburst type phenomena) during takeoff and landing remain as major unsolved design problems from a lack of both environmental data and computational methodology. The development of helicopter and V/STOL dynamic wind and turbulence response computation methology is reviewed, the current state of the design art in industry is outlined, and comments on design methodology are made which may serve to improve future flight vehicle design.

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.

Critical Ethnography: A Useful Methodology in Conducting Health Research in Different Resource Settings

ERIC Educational Resources Information Center

Oladele, Dunsi; Richter, Solina; Clark, Alexander; Laing, Lory

2012-01-01

Over the years, many policies have been implemented across nations to prevent, reduce and tighten enforcement on smoking and tobacco use. However, despite all of the major initiatives, smoking related deaths and diseases still remain high and present a major challenge for many nations of the world. In this paper we argue that conducting a critical…

Conceptual and methodological challenges to integrating SEA and cumulative effects assessment

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

Gunn, Jill, E-mail: jill.gunn@usask.c; Noble, Bram F.

The constraints to assessing and managing cumulative environmental effects in the context of project-based environmental assessment are well documented, and the potential benefits of a more strategic approach to cumulative effects assessment (CEA) are well argued; however, such benefits have yet to be clearly demonstrated in practice. While it is widely assumed that cumulative effects are best addressed in a strategic context, there has been little investigation as to whether CEA and strategic environmental assessment (SEA) are a 'good fit' - conceptually or methodologically. This paper identifies a number of conceptual and methodological challenges to the integration of CEA andmore » SEA. Based on results of interviews with international experts and practitioners, this paper demonstrates that: definitions and conceptualizations of CEA are typically weak in practice; approaches to effects aggregation vary widely; a systems perspective lacks in both SEA and CEA; the multifarious nature of SEA complicates CEA; tiering arrangements between SEA and project-based assessment are limited to non-existing; and the relationship of SEA to regional planning remains unclear.« less

The science of team science: overview of the field and introduction to the supplement.

PubMed

Stokols, Daniel; Hall, Kara L; Taylor, Brandie K; Moser, Richard P

2008-08-01

The science of team science encompasses an amalgam of conceptual and methodologic strategies aimed at understanding and enhancing the outcomes of large-scale collaborative research and training programs. This field has emerged rapidly in recent years, largely in response to growing concerns about the cost effectiveness of public- and private-sector investments in team-based science and training initiatives. The distinctive boundaries and substantive concerns of this field, however, have remained difficult to discern. An important challenge for the field is to characterize the science of team science more clearly in terms of its major theoretical, methodologic, and translational concerns. The articles in this supplement address this challenge, especially in the context of designing, implementing, and evaluating cross-disciplinary research initiatives. This introductory article summarizes the major goals and organizing themes of the supplement, draws links between the constituent articles, and identifies new areas of study within the science of team science.

Inter-Philosophies Dialogue: Creating a Paradigm for Global Health Ethics.

PubMed

Benatar, Solomon; Daibes, Ibrahim; Tomsons, Sandra

While debate remains about the definition and goals of work on global health, there is growing agreement that our moral starting point is the reality of unjust inequalities in the distribution of the conditions necessary for human health and well-being. With the growth of multi-jurisdictional and multicultural global health partnerships, the adequacy of the prevailing bioethical paradigm guiding the conduct of global health research and practice is being increasingly challenged. In response to ethical challenges and conflicts confronted by decision-makers in global health research and practice, we propose an innovative methodology that could be developed to bridge the gap between polarized systems of ideas and values (metaphysical, epistemological, moral, and political). Our inter-philosophies methodology provides the potential to construct a new, shared paradigm for global health ethics, thereby increasing the capacity for solidarity and shared decision-making in global health research and practice.

Methodological Issues in the Collection, Analysis, and Reporting of Granular Data in Asian American Populations: Historical Challenges and Potential Solutions

PubMed Central

Islam, Nadia Shilpi; Khan, Suhaila; Kwon, Simona; Jang, Deeana; Ro, Marguerite; Trinh-Shevrin, Chau

2011-01-01

There are close to 15 million Asian Americans living in the United States, and they represent the fastest growing populations in the country. By the year 2050, there will be an estimated 33.4 million Asian Americans living in the country. However, their health needs remain poorly understood and there is a critical lack of data disaggregated by Asian American ethnic subgroups, primary language, and geography. This paper examines methodological issues, challenges, and potential solutions to addressing the collection, analysis, and reporting of disaggregated (or, granular) data on Asian Americans. The article explores emerging efforts to increase granular data through the use of innovative study design and analysis techniques. Concerted efforts to implement these techniques will be critical to the future development of sound research, health programs, and policy efforts targeting this and other minority populations. PMID:21099084

Review of methodological challenges in comparing the effectiveness of neoadjuvant chemotherapy versus primary debulking surgery for advanced ovarian cancer in the United States.

PubMed

Cole, Ashley L; Austin, Anna E; Hickson, Ryan P; Dixon, Matthew S; Barber, Emma L

2018-05-11

Randomized trials outside the U.S. have found non-inferior survival for neoadjuvant chemotherapy (NACT) versus primary debulking surgery (PDS) for advanced ovarian cancer (AOC). However, these trials reported lower overall survival and lower rates of optimal debulking than U.S. studies, leading to questions about generalizability to U.S. practice, where aggressive debulking is more common. Consequently, comparative effectiveness in the U.S. remains controversial. We reviewed U.S. comparative effectiveness studies of NACT versus PDS for AOC. Here we describe methodological challenges, compare results to trials outside the U.S., and make suggestions for future research. We identified U.S. studies published in 2010 or later that evaluated the comparative effectiveness of NACT versus PDS on survival in AOC through a PubMed search. Two independent reviewers abstracted data from eligible articles. Nine of 230 articles were eligible for review. Methodological challenges included unmeasured confounders, heterogeneous treatment effects, treatment variations over time, and inconsistent measurement of treatment and survival. Whereas some limitations were unavoidable, several limitations noted across studies were avoidable, including conditioning on mediating factors and immortal time introduced by measuring survival beginning from diagnosis. Without trials in the U.S., non-randomized studies are an important source of evidence for the ideal treatment for AOC. However, several methodological challenges exist when assessing the comparative effectiveness of NACT versus PDS in a non-randomized setting. Future observational studies must ensure that treatment is consistent throughout the study period and that treatment groups are comparable. Rapidly-evolving oncology data networks may allow for identification of treatment intent and other important confounders. Copyright © 2018 Elsevier Ltd. All rights reserved.

Return on Investment Analysis for the Almond Board of California

DTIC Science & Technology

2004-06-01

general approach for the analysis is first to identify relevant factors concerning consumer behavior using exploratory factor analysis (EFA) and...That completed the intermediate stage of the conceptual model below, referring to the latent drivers of consumer behavior that affect the almond... consumer behavior remains a challenge that will have to be continuously addressed by the ABC management. Finally, to improve the methodology for

Advanced Methodology for Simulation of Complex Flows Using Structured Grid Systems

NASA Technical Reports Server (NTRS)

Steinthorsson, Erlendur; Modiano, David

1995-01-01

Detailed simulations of viscous flows in complicated geometries pose a significant challenge to current capabilities of Computational Fluid Dynamics (CFD). To enable routine application of CFD to this class of problems, advanced methodologies are required that employ (a) automated grid generation, (b) adaptivity, (c) accurate discretizations and efficient solvers, and (d) advanced software techniques. Each of these ingredients contributes to increased accuracy, efficiency (in terms of human effort and computer time), and/or reliability of CFD software. In the long run, methodologies employing structured grid systems will remain a viable choice for routine simulation of flows in complex geometries only if genuinely automatic grid generation techniques for structured grids can be developed and if adaptivity is employed more routinely. More research in both these areas is urgently needed.

Evaluation of Healthcare Interventions and Big Data: Review of Associated Data Issues.

PubMed

Asche, Carl V; Seal, Brian; Kahler, Kristijan H; Oehrlein, Elisabeth M; Baumgartner, Meredith Greer

2017-08-01

Although the analysis of 'big data' holds tremendous potential to improve patient care, there remain significant challenges before it can be realized. Accuracy and completeness of data, linkage of disparate data sources, and access to data are areas that require particular focus. This article discusses these areas and shares strategies to promote progress. Improvement in clinical coding, innovative matching methodologies, and investment in data standardization are potential solutions to data validation and linkage problems. Challenges to data access still require significant attention with data ownership, security needs, and costs representing significant barriers to access.

Big data analytics in healthcare: promise and potential.

PubMed

Raghupathi, Wullianallur; Raghupathi, Viju

2014-01-01

To describe the promise and potential of big data analytics in healthcare. The paper describes the nascent field of big data analytics in healthcare, discusses the benefits, outlines an architectural framework and methodology, describes examples reported in the literature, briefly discusses the challenges, and offers conclusions. The paper provides a broad overview of big data analytics for healthcare researchers and practitioners. Big data analytics in healthcare is evolving into a promising field for providing insight from very large data sets and improving outcomes while reducing costs. Its potential is great; however there remain challenges to overcome.

Integrated mixed methods policy analysis for sustainable food systems: trends, challenges and future research.

PubMed

Cuevas, Soledad

Agriculture is a major contributor to greenhouse gas emissions, an important part of which is associated to deforestation and indirect land use change. Appropriate and coherent food policies can play an important role in aligning health, economic and environmental goals. From the point of view of policy analysis, however, this requires multi-sectoral, interdisciplinary approaches which can be highly complex. Important methodological advances in the area are not exempted from limitations and criticism. We argue that there is scope for further developments in integrated quantitative and qualitative policy analysis combining existing methods, including mathematical modelling and stakeholder analysis. We outline methodological trends in the field, briefly characterise integrated mixed methods policy analysis and identify contributions, challenges and opportunities for future research. In particular, this type of approach can help address issues of uncertainty and context-specific validity, incorporate multiple perspectives and help advance meaningful interdisciplinary collaboration in the field. Substantial challenges remain, however, such as the integration of key issues related to non-communicable disease, or the incorporation of a broader range of qualitative approaches that can address important cultural and ethical dimensions of food.

Lean Six Sigma in health care and the challenge of implementation of Six Sigma methodologies at a Veterans Affairs Medical Center.

PubMed

Pocha, Christine

2010-01-01

Six Sigma and Lean Thinking are quality initiatives initially deployed in industry to improve operational efficiency leading to better quality and subsequent cost savings. The financial rationale for embarking on this quality journey is clear; applying it to today's health care remains challenging. The cost of medical care is increasing at an alarming rate; most of these cost increases are attributed to an aging population and technological advances; therefore, largely beyond control. Furthermore, health care cost increases are caused by unnecessary operational inefficiency associated with the direct medical service delivery process. This article describes the challenging journey of implementing Six Sigma methodology at a tertiary care medical center. Many lessons were learned; however, of utmost importance were team approach, "buy in" of the stakeholders, and the willingness of team members to change daily practice and to adapt new and innovative ways how health care can be delivered. Six Sigma incorporated as part of the "company's or hospital's culture" would be most desirable but the learning curve will be steep.

Investigating the association between medication adherence and health-related quality of life in COPD: Methodological challenges when using a proxy measure of adherence.

PubMed

Boland, Melinde R S; van Boven, Job F M; Kruis, Annemarije L; Chavannes, Niels H; van der Molen, Thys; Goossens, Lucas M A; Rutten-van Mölken, Maureen P M H

2016-01-01

The association between non-adherence to medication and health-related quality-of-life (HRQoL) in Chronic Obstructive Pulmonary Disease (COPD) remains poorly understood. Different ways to deal with methodological challenges to estimate this association have probably contributed to conflicting results. To investigate the association between medication adherence and HRQoL, thereby illustrating methodological challenges that need to be addressed. We used longitudinal patient-level data from a cluster-randomized controlled trial (i.e. RECODE) including three-year data on type and dose of COPD maintenance medication prescribed and HRQoL (Clinical COPD Questionnaire [CCQ], st. George Respiratory Questionnaire [SGRQ], EuroQol 5-dimensions [EQ-5D]) of 511 patients. A linear mixed model was used to assess the association between adherence and HRQoL using a fixed cut-off of 80% of the proportion of days covered (PDC) to define adherence. Subsequently, we investigated the impact of differences in disease severity; lifestyle; and reversed causality, representing the methodological challenges. Additionally, we investigated the impact of changing the definition of adherence. In unadjusted analyses, and analyses adjusting for demographic characteristics only, SGRQ score was worse in the adherent compared to the non-adherent group. This association disappeared when correcting for disease severity and/or lifestyle. A better SGRQ score was predictive of decreased adherence in the following year. However, accounting for the previous HRQoL did not result in positive associations between adherence and HRQoL. When defining four categories of adherence, patients with a PDC between 80 and 99% had a significantly worse SGRQ score compared to patients with a PDC <60%, even after correction for lifestyle. There was no significant association between adherence and CCQ or EQ-5D. This study showed persistent methodological challenges in the investigation of the effect of medication adherence on HRQoL in COPD. A positive association of adherence and HRQoL was not found, even after adjusting for lifestyle, disease severity, and previous HRQoL. Copyright © 2015. Published by Elsevier Ltd.

Work participation and arthritis: a systematic overview of challenges, adaptations and opportunities for interventions.

PubMed

Hoving, Jan L; van Zwieten, Myra C B; van der Meer, Marrit; Sluiter, Judith K; Frings-Dresen, Monique H W

2013-07-01

Understanding the factors that play a role in maintaining people with inflammatory arthritis in the workforce may aid the design of interventions to support work participation. The objective of this systematic overview is to summarize qualitative studies that explore experiences of patients with inflammatory arthritis to remain employed or return to work. Bibliographic databases including MEDLINE, EMBASE and PsycInfo were searched until December 2011 to identify any qualitative studies that focused on experiences, challenges or adaptations of patients with inflammatory arthritis to remain employed. Thematic analyses were used to identify any first or higher order themes for which all data were entered into MAXQDA software. In addition, methodological quality was assessed using an eight-item checklist. Of 6338 citations, 10 studies were included. RA was the condition in eight studies. Individual interviews (six studies) were used more frequently than group interviews (four studies). Methodological quality varied from 2 to 8 points and had no effect on the number of themes identified. Thematic analyses showed seven key concepts important to patients, including disease symptoms, management of the disease, socioeconomic issues, work conditions and adaptations, emotional challenges, interpersonal issues affecting work and family life and meaning of work. By including studies from different countries and settings, we show a comprehensive overview of themes considered important by patients and strengthen our belief that these factors should be considered in interventions that aim to improve work participation for patients with inflammatory arthritis.

Mental health consequences of international migration for Vietnamese Americans and the mediating effects of physical health and social networks: results from a natural experiment approach.

PubMed

Fu, Hongyun; VanLandingham, Mark J

2012-05-01

Although the existing literature on immigrant mental health is extensive, major substantive and methodological gaps remain. Substantively, there is little population-based research that focuses on the mental health consequences of migration for Vietnamese Americans. More generally, although a wide range of mental health problems among immigrants has been identified, the potential causal or mediating mechanisms underlying these problems remain elusive. This latter substantive shortcoming is related to a key methodological challenge involving the potentially confounding effects of selection on migration-related outcomes. This article addresses these challenges by employing a "natural experiment" design, involving comparisons among three population-based samples of Vietnamese immigrants, never-leavers, and returnees (N=709). Data were collected in Ho Chi Minh City and in New Orleans between 2003 and 2005. The study investigates the long-term impact of international migration on Vietnamese mental health, and the potential mediating effects of social networks and physical health on these migration-related outcomes. The results reveal both mental health advantages and disadvantages among Vietnamese immigrants relative to the two groups of Vietnamese nationals. Selection can be ruled out for some of these differences, and both social networks and physical health are found to play important explanatory roles.

FDAAA legislation is working, but methodological flaws undermine the reliability of clinical trials: a cross-sectional study.

PubMed

Marin Dos Santos, Douglas H; Atallah, Álvaro N

2015-01-01

The relationship between clinical research and the pharmaceutical industry has placed clinical trials in jeopardy. According to the medical literature, more than 70% of clinical trials are industry-funded. Many of these trials remain unpublished or have methodological flaws that distort their results. In 2007, it was signed into law the Food and Drug Administration Amendments Act (FDAAA), aiming to provide publicly access to a broad range of biomedical information to be made available on the platform ClinicalTrials (available at https://www.clinicaltrials.gov). We accessed ClinicalTrials.gov and evaluated the compliance of researchers and sponsors with the FDAAA. Our sample comprised 243 protocols of clinical trials of biological monoclonal antibodies (mAb) adalimumab, bevacizumab, infliximab, rituximab, and trastuzumab. We demonstrate that the new legislation has positively affected transparency patterns in clinical research, through a significant increase in publication and online reporting rates after the enactment of the law. Poorly designed trials, however, remain a challenge to be overcome, due to a high prevalence of methodological flaws. These flaws affect the quality of clinical information available, breaching ethical duties of sponsors and researchers, as well as the human right to health.

FDAAA legislation is working, but methodological flaws undermine the reliability of clinical trials: a cross-sectional study

PubMed Central

Atallah, Álvaro N.

2015-01-01

The relationship between clinical research and the pharmaceutical industry has placed clinical trials in jeopardy. According to the medical literature, more than 70% of clinical trials are industry-funded. Many of these trials remain unpublished or have methodological flaws that distort their results. In 2007, it was signed into law the Food and Drug Administration Amendments Act (FDAAA), aiming to provide publicly access to a broad range of biomedical information to be made available on the platform ClinicalTrials (available at https://www.clinicaltrials.gov). We accessed ClinicalTrials.gov and evaluated the compliance of researchers and sponsors with the FDAAA. Our sample comprised 243 protocols of clinical trials of biological monoclonal antibodies (mAb) adalimumab, bevacizumab, infliximab, rituximab, and trastuzumab. We demonstrate that the new legislation has positively affected transparency patterns in clinical research, through a significant increase in publication and online reporting rates after the enactment of the law. Poorly designed trials, however, remain a challenge to be overcome, due to a high prevalence of methodological flaws. These flaws affect the quality of clinical information available, breaching ethical duties of sponsors and researchers, as well as the human right to health. PMID:26131374

Methodological issues in the design and analyses of neonatal research studies: Experience of the NICHD Neonatal Research Network.

PubMed

Das, Abhik; Tyson, Jon; Pedroza, Claudia; Schmidt, Barbara; Gantz, Marie; Wallace, Dennis; Truog, William E; Higgins, Rosemary D

2016-10-01

Impressive advances in neonatology have occurred over the 30 years of life of The Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network (NRN). However, substantial room for improvement remains in investigating and further developing the evidence base for improving outcomes among the extremely premature. We discuss some of the specific methodological challenges in the statistical design and analysis of randomized trials and observational studies in this population. Challenges faced by the NRN include designing trials for unusual or rare outcomes, accounting for and explaining center variations, identifying other subgroup differences, and balancing safety and efficacy concerns between short-term hospital outcomes and longer-term neurodevelopmental outcomes. In conclusion, the constellation of unique patient characteristics in neonates calls for broad understanding and careful consideration of the issues identified in this article for conducting rigorous studies in this population. Copyright © 2016 Elsevier Inc. All rights reserved.

Comparative Effectiveness Research in Oncology

PubMed Central

2013-01-01

Although randomized controlled trials represent the gold standard for comparative effective research (CER), a number of additional methods are available when randomized controlled trials are lacking or inconclusive because of the limitations of such trials. In addition to more relevant, efficient, and generalizable trials, there is a need for additional approaches utilizing rigorous methodology while fully recognizing their inherent limitations. CER is an important construct for defining and summarizing evidence on effectiveness and safety and comparing the value of competing strategies so that patients, providers, and policymakers can be offered appropriate recommendations for optimal patient care. Nevertheless, methodological as well as political and social challenges for CER remain. CER requires constant and sophisticated methodological oversight of study design and analysis similar to that required for randomized trials to reduce the potential for bias. At the same time, if appropriately conducted, CER offers an opportunity to identify the most effective and safe approach to patient care. Despite rising and unsustainable increases in health care costs, an even greater challenge to the implementation of CER arises from the social and political environment questioning the very motives and goals of CER. Oncologists and oncology professional societies are uniquely positioned to provide informed clinical and methodological expertise to steer the appropriate application of CER toward critical discussions related to health care costs, cost-effectiveness, and the comparative value of the available options for appropriate care of patients with cancer. PMID:23697601

On a methodology for robust segmentation of nonideal iris images.

PubMed

Schmid, Natalia A; Zuo, Jinyu

2010-06-01

Iris biometric is one of the most reliable biometrics with respect to performance. However, this reliability is a function of the ideality of the data. One of the most important steps in processing nonideal data is reliable and precise segmentation of the iris pattern from remaining background. In this paper, a segmentation methodology that aims at compensating various nonidealities contained in iris images during segmentation is proposed. The virtue of this methodology lies in its capability to reliably segment nonideal imagery that is simultaneously affected with such factors as specular reflection, blur, lighting variation, occlusion, and off-angle images. We demonstrate the robustness of our segmentation methodology by evaluating ideal and nonideal data sets, namely, the Chinese Academy of Sciences iris data version 3 interval subdirectory, the iris challenge evaluation data, the West Virginia University (WVU) data, and the WVU off-angle data. Furthermore, we compare our performance to that of our implementation of Camus and Wildes's algorithm and Masek's algorithm. We demonstrate considerable improvement in segmentation performance over the formerly mentioned algorithms.

Cancer and aging: Epidemiology and methodological challenges.

PubMed

Pedersen, Jacob K; Engholm, Gerda; Skytthe, Axel; Christensen, Kaare

2016-01-01

Epidemiological cancer data shed light on key questions within basic science, clinical medicine and public health. For decades, Denmark has had linkable health registers that contain individual level data on the entire population with virtually complete follow-up. This has enabled high quality studies of cancer epidemiology and minimized the challenges often faced in many countries, such as uncertain identification of the study base, age misreporting, and low validity of the cancer diagnoses. However, methodological challenges still remain to be addressed, especially in cancer epidemiology studies among the elderly and the oldest-old. For example, a characteristic pattern for many cancer types is that the incidence increases up to a maximum at about ages 75-90 years and is then followed by a decline or a leveling off at the oldest ages. It has been suggested that the oldest individuals may be asymptomatic, or even insusceptible to cancer. An alternative interpretation is that this pattern is an artifact due to lower diagnostic intensity among the elderly and oldest-old caused by higher levels of co-morbidities in this age group. Currently, the available cancer epidemiology data are not able to provide clear evidence for any of these hypotheses.

Analysis of torque transmitting behavior and wheel slip prevention control during regenerative braking for high speed EMU trains

NASA Astrophysics Data System (ADS)

Xu, Kun; Xu, Guo-Qing; Zheng, Chun-Hua

2016-04-01

The wheel-rail adhesion control for regenerative braking systems of high speed electric multiple unit trains is crucial to maintaining the stability, improving the adhesion utilization, and achieving deep energy recovery. There remain technical challenges mainly because of the nonlinear, uncertain, and varying features of wheel-rail contact conditions. This research analyzes the torque transmitting behavior during regenerative braking, and proposes a novel methodology to detect the wheel-rail adhesion stability. Then, applications to the wheel slip prevention during braking are investigated, and the optimal slip ratio control scheme is proposed, which is based on a novel optimal reference generation of the slip ratio and a robust sliding mode control. The proposed methodology achieves the optimal braking performance without the wheel-rail contact information. Numerical simulation results for uncertain slippery rails verify the effectiveness of the proposed methodology.

Rovers minimize human disturbance in research on wild animals.

PubMed

Le Maho, Yvon; Whittington, Jason D; Hanuise, Nicolas; Pereira, Louise; Boureau, Matthieu; Brucker, Mathieu; Chatelain, Nicolas; Courtecuisse, Julien; Crenner, Francis; Friess, Benjamin; Grosbellet, Edith; Kernaléguen, Laëtitia; Olivier, Frédérique; Saraux, Claire; Vetter, Nathanaël; Viblanc, Vincent A; Thierry, Bernard; Tremblay, Pascale; Groscolas, René; Le Bohec, Céline

2014-12-01

Investigating wild animals while minimizing human disturbance remains an important methodological challenge. When approached by a remote-operated vehicle (rover) which can be equipped to make radio-frequency identifications, wild penguins had significantly lower and shorter stress responses (determined by heart rate and behavior) than when approached by humans. Upon immobilization, the rover-unlike humans-did not disorganize colony structure, and stress rapidly ceased. Thus, rovers can reduce human disturbance of wild animals and the resulting scientific bias.

GABA abnormalities in schizophrenia: a methodological review of in vivo studies.

PubMed

Taylor, Stephan F; Tso, Ivy F

2015-09-01

Abnormalities of GABAergic interneurons are some of the most consistent findings from post-mortem studies of schizophrenia. However, linking these molecular deficits with in vivo observations in patients - a critical goal in order to evaluate interventions that would target GABAergic deficits - presents a challenge. Explanatory models have been developed based on animal work and the emerging experimental literature in schizophrenia patients. This literature includes: neuroimaging ligands to GABA receptors, magnetic resonance spectroscopy (MRS) of GABA concentration, transcranial magnetic stimulation of cortical inhibitory circuits and pharmacologic probes of GABA receptors to dynamically challenge the GABA system, usually in combination with neuroimaging studies. Pharmacologic challenges have elicited behavioral changes, and preliminary studies of therapeutic GABAergic interventions have been conducted. This article critically reviews the evidence for GABAergic dysfunction from each of these areas. These methods remain indirect measures of GABAergic function, and a broad array of dysfunction is linked with the putative GABAergic measures, including positive symptoms, cognition, emotion, motor processing and sensory processing, covering diverse brain areas. Measures of receptor binding have not shown replicable group differences in binding, and MRS assays of GABA concentration have yielded equivocal evidence of large-scale alteration in GABA concentration. Overall, the experimental base remains sparse, and much remains to be learned about the role of GABAergic interneurons in healthy brains. Challenges with pharmacologic and functional probes show promise, and may yet enable a better characterization of GABAergic deficits in schizophrenia. Copyright © 2014 Elsevier B.V. All rights reserved.

Translating multilevel theory into multilevel research: Challenges and opportunities for understanding the social determinants of psychiatric disorders

PubMed Central

Dunn, Erin C.; Masyn, Katherine E.; Yudron, Monica; Jones, Stephanie M.; Subramanian, S.V.

2014-01-01

The observation that features of the social environment, including family, school, and neighborhood characteristics, are associated with individual-level outcomes has spurred the development of dozens of multilevel or ecological theoretical frameworks in epidemiology, public health, psychology, and sociology, among other disciplines. Despite the widespread use of such theories in etiological, intervention, and policy studies, challenges remain in bridging multilevel theory and empirical research. This paper set out to synthesize these challenges and provide specific examples of methodological and analytical strategies researchers are using to gain a more nuanced understanding of the social determinants of psychiatric disorders, with a focus on children’s mental health. To accomplish this goal, we begin by describing multilevel theories, defining their core elements, and discussing what these theories suggest is needed in empirical work. In the second part, we outline the main challenges researchers face in translating multilevel theory into research. These challenges are presented for each stage of the research process. In the third section, we describe two methods being used as alternatives to traditional multilevel modeling techniques to better bridge multilevel theory and multilevel research. These are: (1) multilevel factor analysis and multilevel structural equation modeling; and (2) dynamic systems approaches. Through its review of multilevel theory, assessment of existing strategies, and examination of emerging methodologies, this paper offers a framework to evaluate and guide empirical studies on the social determinants of child psychiatric disorders as well as health across the lifecourse. PMID:24469555

Triage and the Lost Art of Decoding Vital Signs: Restoring Physiologically Based Triage Skills in Complex Humanitarian Emergencies.

PubMed

Burkle, Frederick M

2018-02-01

Triage management remains a major challenge, especially in resource-poor settings such as war, complex humanitarian emergencies, and public health emergencies in developing countries. In triage it is often the disruption of physiology, not anatomy, that is critical, supporting triage methodology based on clinician-assessed physiological parameters as well as anatomy and mechanism of injury. In recent times, too many clinicians from developed countries have deployed to humanitarian emergencies without the physical exam skills needed to assess patients without the benefit of remotely fed electronic monitoring, laboratory, and imaging studies. In triage, inclusion of the once-widely accepted and collectively taught "art of decoding vital signs" with attention to their character and meaning may provide clues to a patient's physiological state, improving triage sensitivity. Attention to decoding vital signs is not a triage methodology of its own or a scoring system, but rather a skill set that supports existing triage methodologies. With unique triage management challenges being raised by an ever-changing variety of humanitarian crises, these once useful skill sets need to be revisited, understood, taught, and utilized by triage planners, triage officers, and teams as a necessary adjunct to physiologically based triage decision-making. (Disaster Med Public Health Preparedness. 2018;12:76-85).

How to Tackle Key Challenges in the Promotion of Physical Activity among Older Adults (65+): The AEQUIPA Network Approach

PubMed Central

Forberger, Sarah; Bammann, Karin; Bauer, Jürgen; Boll, Susanne; Bolte, Gabriele; Brand, Tilman; Hein, Andreas; Koppelin, Frauke; Lippke, Sonia; Meyer, Jochen; Pischke, Claudia R.; Voelcker-Rehage, Claudia; Zeeb, Hajo

2017-01-01

The paper introduces the theoretical framework and methods/instruments used by the Physical Activity and Health Equity: Primary Prevention for Healthy Ageing (AEQUIPA) prevention research network as an interdisciplinary approach to tackle key challenges in the promotion of physical activity among older people (65+). Drawing on the social-ecological model, the AEQUIPA network developed an interdisciplinary methodological design including quantitative/qualitative studies and systematic reviews, while combining expertise from diverse fields: public health, psychology, urban planning, sports sciences, health technology and geriatrics. AEQUIPA tackles key challenges when promoting physical activity (PA) in older adults: tailoring of interventions, fostering community readiness and participation, strengthening intersectoral collaboration, using new technological devices and evaluating intervention generated inequalities. AEQUIPA aims to strengthen the evidence base for age-specific preventive PA interventions and to yield new insights into the explanatory power of individual and contextual factors. Currently, the empirical work is still underway. First experiences indicate that the network has achieved a strong regional linkage with communities, local stakeholders and individuals. However, involving inactive persons and individuals from minority groups remained challenging. A review of existing PA intervention studies among the elderly revealed the potential to assess equity effects. The results will add to the theoretical and methodological discussion on evidence-based age-specific PA interventions and will contribute to the discussion about European and national health targets. PMID:28375177

How to Tackle Key Challenges in the Promotion of Physical Activity among Older Adults (65+): The AEQUIPA Network Approach.

PubMed

Forberger, Sarah; Bammann, Karin; Bauer, Jürgen; Boll, Susanne; Bolte, Gabriele; Brand, Tilman; Hein, Andreas; Koppelin, Frauke; Lippke, Sonia; Meyer, Jochen; Pischke, Claudia R; Voelcker-Rehage, Claudia; Zeeb, Hajo

2017-04-04

The paper introduces the theoretical framework and methods/instruments used by the Physical Activity and Health Equity: Primary Prevention for Healthy Ageing (AEQUIPA) prevention research network as an interdisciplinary approach to tackle key challenges in the promotion of physical activity among older people (65+). Drawing on the social-ecological model, the AEQUIPA network developed an interdisciplinary methodological design including quantitative/qualitative studies and systematic reviews, while combining expertise from diverse fields: public health, psychology, urban planning, sports sciences, health technology and geriatrics. AEQUIPA tackles key challenges when promoting physical activity (PA) in older adults: tailoring of interventions, fostering community readiness and participation, strengthening intersectoral collaboration, using new technological devices and evaluating intervention generated inequalities. AEQUIPA aims to strengthen the evidence base for age-specific preventive PA interventions and to yield new insights into the explanatory power of individual and contextual factors. Currently, the empirical work is still underway. First experiences indicate that thenetwork has achieved a strong regional linkage with communities, local stakeholders and individuals. However, involving inactive persons and individuals from minority groups remained challenging. A review of existing PA intervention studies among the elderly revealed the potential to assess equity effects. The results will add to the theoretical and methodological discussion on evidence-based age-specific PA interventions and will contribute to the discussion about European and national health targets.

Symptom research on chronic cough: a historical perspective.

PubMed

Irwin, R S; Madison, J M

2001-05-01

This review provides a perspective on how research on the management of cough has evolved, looks at key methodologic lessons that have been learned from this research and how they may relate to the management of other symptoms, identifies important methodologic challenges that remain to be solved, and lists important questions that still need to be answered. Three important methodologic lessons have been learned. First, cough must be evaluated systematically and according to a neuroanatomic framework. Second, the response to specific therapy must be noted to determine the cause or causes of cough and to characterize the strengths and limitations of diagnostic testing. Third, multiple conditions can simultaneously cause cough. Among the three methodologic challenges that still need to be solved are 1) definitively determining the diagnostic accuracy and reliability of 24-hour esophageal pH monitoring and how best to interpret pH test results, 2) definitively determining the role of nonacid reflux in cough due to gastroesophageal reflux disease, and 3) developing reliable and reproducible subjective and objective methods with which to assess the efficacy of cough therapy. Numerous important clinical questions are still unanswered: What role do empirical therapeutic trials play in diagnosing the cause of chronic cough? What is the most cost-effective approach to the diagnosis and treatment of chronic cough: empirical therapeutic trials or laboratory testing-directed therapeutic trials? How often is environmental air pollution, unrelated to allergies or smoking, responsible for chronic cough?

Evaluation of complex community-based childhood obesity prevention interventions.

PubMed

Karacabeyli, D; Allender, S; Pinkney, S; Amed, S

2018-05-16

Multi-setting, multi-component community-based interventions have shown promise in preventing childhood obesity; however, evaluation of these complex interventions remains a challenge. The objective of the study is to systematically review published methodological approaches to outcome evaluation for multi-setting community-based childhood obesity prevention interventions and synthesize a set of pragmatic recommendations. MEDLINE, CINAHL and PsycINFO were searched from inception to 6 July 2017. Papers were included if the intervention targeted children ≤18 years, engaged at least two community sectors and described their outcome evaluation methodology. A single reviewer conducted title and abstract scans, full article review and data abstraction. Directed content analysis was performed by three reviewers to identify prevailing themes. Thirty-three studies were included, and of these, 26 employed a quasi-experimental design; the remaining were randomized control trials. Body mass index was the most commonly measured outcome, followed by health behaviour change and psychosocial outcomes. Six themes emerged, highlighting advantages and disadvantages of active vs. passive consent, quasi-experimental vs. randomized control trials, longitudinal vs. repeat cross-sectional designs and the roles of process evaluation and methodological flexibility in evaluating complex interventions. Selection of study designs and outcome measures compatible with community infrastructure, accompanied by process evaluation, may facilitate successful outcome evaluation. © 2018 World Obesity Federation.

REDItools: high-throughput RNA editing detection made easy.

PubMed

Picardi, Ernesto; Pesole, Graziano

2013-07-15

The reliable detection of RNA editing sites from massive sequencing data remains challenging and, although several methodologies have been proposed, no computational tools have been released to date. Here, we introduce REDItools a suite of python scripts to perform high-throughput investigation of RNA editing using next-generation sequencing data. REDItools are in python programming language and freely available at http://code.google.com/p/reditools/. ernesto.picardi@uniba.it or graziano.pesole@uniba.it Supplementary data are available at Bioinformatics online.

Copper-facilitated Suzuki reactions: application to 2-heterocyclic boronates.

PubMed

Deng, James Z; Paone, Daniel V; Ginnetti, Anthony T; Kurihara, Hideki; Dreher, Spencer D; Weissman, Steven A; Stauffer, Shaun R; Burgey, Christopher S

2009-01-15

The palladium-catalyzed Suzuki-Miyaura reaction has been utilized as one of the most powerful methods for C-C bond formation. However, Suzuki reactions of electron-deficient 2-heterocyclic boronates generally give low conversions and remain challenging. The successful copper(I) facilitated Suzuki coupling of 2-heterocyclic boronates that is broad in scope is reported. Use of this methodology affords greatly enhanced yields of these notoriously difficult couplings. Furthermore, mechanistic investigations suggest a possible role of copper in the catalytic cycle.

Pediatric microdose and microtracer studies using 14C in Europe.

PubMed

Turner, M A; Mooij, M G; Vaes, W H J; Windhorst, A D; Hendrikse, N H; Knibbe, C A J; Kõrgvee, L T; Maruszak, W; Grynkiewicz, G; Garner, R C; Tibboel, D; Park, B K; de Wildt, S N

2015-09-01

Important information gaps remain on the efficacy and safety of drugs in children. Pediatric drug development encounters several ethical, practical, and scientific challenges. One barrier to the evaluation of medicines for children is a lack of innovative methodologies that have been adapted to the needs of children. This article presents our successful experience of pediatric microdose and microtracer studies using (14) C-labeled probes in Europe to illustrate the strengths and limitations of these approaches. © 2015 ASCPT.

Non-Destructive Sampling of Ancient Insect DNA

PubMed Central

Thomsen, Philip Francis; Elias, Scott; Gilbert, M. Thomas P.; Haile, James; Munch, Kasper; Kuzmina, Svetlana; Froese, Duane G.; Holdaway, Richard N.; Willerslev, Eske

2009-01-01

Background A major challenge for ancient DNA (aDNA) studies on insect remains is that sampling procedures involve at least partial destruction of the specimens. A recent extraction protocol reveals the possibility of obtaining DNA from past insect remains without causing visual morphological damage. We test the applicability of this protocol on historic museum beetle specimens dating back to AD 1820 and on ancient beetle chitin remains from permafrost (permanently frozen soil) dating back more than 47,000 years. Finally, we test the possibility of obtaining ancient insect DNA directly from non-frozen sediments deposited 3280-1800 years ago - an alternative approach that also does not involve destruction of valuable material. Methodology/Principal Findings The success of the methodological approaches are tested by PCR and sequencing of COI and 16S mitochondrial DNA (mtDNA) fragments of 77–204 base pairs (-bp) in size using species-specific and general insect primers. Conclusion/Significance The applied non-destructive DNA extraction method shows promising potential on insect museum specimens of historical age as far back as AD 1820, but less so on the ancient permafrost-preserved insect fossil remains tested, where DNA was obtained from samples up to ca. 26,000 years old. The non-frozen sediment DNA approach appears to have great potential for recording the former presence of insect taxa not normally preserved as macrofossils and opens new frontiers in research on ancient biodiversity. PMID:19337382

Regulating the economic evaluation of pharmaceuticals and medical devices: a European perspective.

PubMed

Cookson, Richard; Hutton, John

2003-02-01

Throughout the developed world, economic evaluation of costly new pharmaceuticals and medical devices became increasingly widespread and systematic during the 1990s. However, serious concerns remain about the validity and relevance of this economic evidence, and about the transparency and accountability of its use in public sector reimbursement decisions. In this article, we summarise current concerns in Europe, based on interviews with European health economists from industry, universities, research institutes and consulting firms. We identify five challenges for European policy-makers, and conclude that there is considerable scope for improving decision-making without damaging incentives to innovate. The challenges are: (1). full publication of the economic evidence used in reimbursement decisions; (2). the redesign of licensing laws to improve the relevance of economic data available at product launch; (3). harmonisation of economic evaluation methodologies; (4). development of methodologies for evaluation of health inequality impacts; and (5). negotiation of price-performance deals to facilitate the use of economic evidence in post-launch pricing review decisions, as information is gathered from studies of product performance in routine use.

Education Research: The challenge of incorporating formal research methodology training in a neurology residency.

PubMed

Leira, E C; Granner, M A; Torner, J C; Callison, R C; Adams, H P

2008-05-13

Physicians often do not have good understanding of research methodology. Unfortunately, the mechanism to achieve this important competency in a busy neurology residency program remains unclear. We tested the value and degree of acceptance by neurology residents of a multimodal educational intervention that consisted of biweekly teaching sessions in place of an existing journal club, as a way to provide formal training in research and statistical techniques. We used a pre- and post-test design with an educational intervention in between using neurology residents at the University of Iowa as subjects. Each test had 40 questions of research methodology. The educational intervention consisted of a biweekly, structured, topic-centered, research methodology-oriented elective seminar following a year-long predefined curriculum. An exit survey was offered to gather resident's perceptions about the course. While a majority of residents agreed that the intervention enhanced their knowledge of research methodology, only 23% attended more than 40% of the sessions. There was no difference between pretest and post-test scores (p = 0.40). Our experience suggests that, in order to accomplish the Accreditation Council for Graduate Medical Education goals regarding increasing competency of residents in knowledge about research methodology, a major restructuring in the neurology residency curriculum with more intense formal training would be necessary.

Speed Accuracy Tradeoffs in Human Speech Production

DTIC Science & Technology

2017-05-01

for considering Fitts’ law in the domain of speech production is elucidated. Methodological challenges in applying Fitts-style analysis are addressed...order to assess whether articulatory kinematics conform to Fitts’ law. A second, associated goal is to address the methodological challenges inherent in...performing Fitts-style analysis on rtMRI data of speech production. Methodological challenges include segmenting continuous speech into specific motor

Quantifying Drosophila food intake: comparative analysis of current methodology

PubMed Central

Deshpande, Sonali A.; Carvalho, Gil B.; Amador, Ariadna; Phillips, Angela M.; Hoxha, Sany; Lizotte, Keith J.; Ja, William W.

2014-01-01

Food intake is a fundamental parameter in animal studies. Despite the prevalent use of Drosophila in laboratory research, precise measurements of food intake remain challenging in this model organism. Here, we compare several common Drosophila feeding assays: the Capillary Feeder (CAFE), food-labeling with a radioactive tracer or a colorimetric dye, and observations of proboscis extension (PE). We show that the CAFE and radioisotope-labeling provide the most consistent results, have the highest sensitivity, and can resolve differences in feeding that dye-labeling and PE fail to distinguish. We conclude that performing the radiolabeling and CAFE assays in parallel is currently the best approach for quantifying Drosophila food intake. Understanding the strengths and limitations of food intake methodology will greatly advance Drosophila studies of nutrition, behavior, and disease. PMID:24681694

Packing of Fruit Fly Parasitoids for Augmentative Releases

PubMed Central

Montoya, Pablo; Cancino, Jorge; Ruiz, Lía

2012-01-01

The successful application of Augmentative Biological Control (ABC) to control pest fruit flies (Diptera: Tephritidae) confronts two fundamental requirements: (1) the establishment of efficient mass rearing procedures for the species to be released, and (2) the development of methodologies for the packing and release of parasitoids that permit a uniform distribution and their optimal field performance under an area-wide approach. Parasitoid distributions have been performed by ground and by air with moderate results; both options face challenges that remain to be addressed. Different devices and strategies have been used for these purposes, including paper bags and the chilled adult technique, both of which are commonly used when releasing sterile flies. However, insect parasitoids have morphological and behavioral characteristics that render the application of such methodologies suboptimal. In this paper, we discuss an alternate strategy for the augmentative release of parasitoids and describe packing conditions that favor the rearing and emergence of adult parasitoids for increased field performance. We conclude that the use of ABC, including the packaging of parasitoids, requires ongoing development to ensure that this technology remains a viable and effective control technique for pest fruit flies. PMID:26466634

Studying Sexual Aggression: A Review of the Evolution and Validity of Laboratory Paradigms

PubMed Central

Davis, Kelly Cue; George, William H.; Nagayama Hall, Gordon C.; Parrott, Dominic J.; Tharp, Andra Teten; Stappenbeck, Cynthia A.

2018-01-01

Objective Researchers have endeavored for decades to develop and implement experimental assessments of sexual aggression and its precursors to capitalize on the many scientific advantages offered by laboratory experiments, such as rigorous control of key variables and identification of causal relationships. The purpose of this review is to provide an overview of and commentary on the evolution of these laboratory-based methods. Conclusions To date, two primary types of sexual aggression laboratory studies have been developed: those that involve behavioral analogues of sexual aggression and those that assess postulated precursors to sexually aggressive behavior. Although the study of sexual aggression in the laboratory is fraught with methodological challenges, validity concerns, and ethical considerations, advances in the field have resulted in greater methodological rigor, more precise dependent measures, and improved experimental validity, reliability, and realism. Because highly effective sexual aggression prevention strategies remain elusive, continued laboratory-based investigation of sexual aggression coupled with translation of critical findings to the development and modification of sexual aggression prevention programs remains an important task for the field. PMID:29675289

Methodological challenges to human medical study.

PubMed

Zhong, Yixin; Liu, Baoyan; Qu, Hua; Xie, Qi

2014-09-01

With the transformation of modern medicinal pattern, medical studies are confronted with methodological challenges. By analyzing two methodologies existing in the study of physical matter system and information system, the article points out that traditional Chinese medicine (TCM), especially the treatment based on syndrome differentiation, embodies information conception of methodological positions, while western medicine represents matter conception of methodological positions. It proposes a new way of thinking about combination of TCM and western medicine by combinating two kinds of methodological methods.

Applications of physiological bases of ageing to forensic sciences. Estimation of age-at-death.

PubMed

C Zapico, Sara; Ubelaker, Douglas H

2013-03-01

Age-at-death estimation is one of the main challenges in forensic sciences since it contributes to the identification of individuals. There are many anthropological techniques to estimate the age at death in children and adults. However, in adults this methodology is less accurate and requires population specific references. For that reason, new methodologies have been developed. Biochemical methods are based on the natural process of ageing, which induces different biochemical changes that lead to alterations in cells and tissues. In this review, we describe different attempts to estimate the age in adults based on these changes. Chemical approaches imply modifications in molecules or accumulation of some products. Molecular biology approaches analyze the modifications in DNA and chromosomes. Although the most accurate technique appears to be aspartic acid racemization, it is important to take into account the other techniques because the forensic context and the human remains available will determine the possibility to apply one or another methodology. Copyright © 2013 Elsevier B.V. All rights reserved.

Methodological difficulties in the conduct of neuroepidemiological studies in low- and middle-income countries.

PubMed

Bharucha, Nadir; Odermatt, Peter; Preux, Pierre-Marie

2014-01-01

The majority of people with epilepsy (PWE) live in low- and middle-income countries (LMICs). However, they remain largely untreated and the bulk of resources are used to treat patients in the developed world. This disparity constitutes a challenge for neuroepidemiological studies on a global scale. In the past, several studies have focused on diverse populations in disparate countries at various periods of time and for particular purposes. The specificity of different contexts and circumstances makes it difficult to analyse PWE as a group either qualitatively or quantitatively. Such methodological limitations are further complicated by a lack of logistical support. There is a lack of interest in conducting studies, which results in inadequate funding and, in addition, there is the considerable challenge of publishing research reports from LMICs in peer-reviewed international journals. This paper focuses on methodological problems related to studies in LMICs and attempts to give the reasons for their limitations using epilepsy as an example. Regional conditions and environmental factors must be given careful consideration in the research design because of the importance of understanding the challenges of living in these environments. There are further limitations to the successful implementation of studies. Existing information on epilepsy is often not readily accessible; there is a lack of census data, and migratory patterns into cities make enumeration and sampling even more challenging. As there is usually no well-developed healthcare system a door-to-door screening process is often the only way to identify those with convulsive epilepsy. The questionnaire and study design should preferably be adapted from standardized protocols, and pre-tested and validated in local conditions. Systematic reviews and meta-analyses of studies in LMICs can provide data on the burden, risk factors, treatment and outcome of epilepsy only if the primary studies used are properly conducted using uniform and comparable methodology. The use of consistent replicable neuroepidemiological methods in primary studies and systematic reviews enable reduction of the treatment gap and better epilepsy care. © 2013 S. Karger AG, Basel.

Target enrichment and high-throughput sequencing of 80 ribosomal protein genes to identify mutations associated with Diamond-Blackfan anaemia.

PubMed

Gerrard, Gareth; Valgañón, Mikel; Foong, Hui En; Kasperaviciute, Dalia; Iskander, Deena; Game, Laurence; Müller, Michael; Aitman, Timothy J; Roberts, Irene; de la Fuente, Josu; Foroni, Letizia; Karadimitris, Anastasios

2013-08-01

Diamond-Blackfan anaemia (DBA) is caused by inactivating mutations in ribosomal protein (RP) genes, with mutations in 13 of the 80 RP genes accounting for 50-60% of cases. The remaining 40-50% cases may harbour mutations in one of the remaining RP genes, but the very low frequencies render conventional genetic screening as challenging. We, therefore, applied custom enrichment technology combined with high-throughput sequencing to screen all 80 RP genes. Using this approach, we identified and validated inactivating mutations in 15/17 (88%) DBA patients. Target enrichment combined with high-throughput sequencing is a robust and improved methodology for the genetic diagnosis of DBA. © 2013 John Wiley & Sons Ltd.

Collecting and validating experiential expertise is doable but poses methodological challenges.

PubMed

Burda, Marika H F; van den Akker, Marjan; van der Horst, Frans; Lemmens, Paul; Knottnerus, J André

2016-04-01

To give an overview of important methodological challenges in collecting, validating, and further processing experiential expertise and how to address these challenges. Based on our own experiences in studying the concept, operationalization, and contents of experiential expertise, we have formulated methodological issues regarding the inventory and application of experiential expertise. The methodological challenges can be categorized in six developmental research stages, comprising the conceptualization of experiential expertise, methods to harvest experiential expertise, the validation of experiential expertise, evaluation of the effectiveness, how to translate experiential expertise into acceptable guidelines, and how to implement these. The description of methodological challenges and ways to handle those are illustrated using diabetes mellitus as an example. Experiential expertise can be defined and operationalized in terms of successful illness-related behaviors and translated into recommendations regarding life domains. Pathways have been identified to bridge the gaps between the world of patients' daily lives and the medical world. Copyright © 2016 Elsevier Inc. All rights reserved.

Applying ethnography to the study of context in healthcare quality and safety.

PubMed

Leslie, Myles; Paradis, Elise; Gropper, Michael A; Reeves, Scott; Kitto, Simon

2014-02-01

Translating and scaling healthcare quality improvement (QI) and patient safety interventions remains a significant challenge. Context has been identified as a major factor in this. QI and patient safety research have begun to focus on context, with ethnography seen as a promising methodology for understanding the professional, organisational and cultural aspects of context. While ethnography is used to investigate the context of a variety of QI and safety interventions, the challenges inherent in effectively importing a qualitative methodology and its social science practitioners into this work have been largely unexamined. We explain ethnography as a research practice grounded in theory and dependent on observations gathered and interpreted in particular ways. We then review the approach of health services literature to evaluating this sort of qualitative research. Although the study of context is an interest shared by both social scientists and healthcare QI and safety researchers, we identify three key points at which those 'exporting' ethnography as a methodology and those 'importing' it to deal with QI and safety challenges may diverge. We describe perspectival divergences on the methodology's mission, form and scale. At the level of mission we demonstrate how ethnography has been adapted to a 'describe and feed back' role in the service of QI. At the level of form, we show how the long-term embedded observation at the heart of ethnography can be adapted only so far to accommodate QI interests if both data quality and ethical standards are to be upheld. Finally, at the level of scale, we demonstrate one ethnographic study design that balances breadth of exposure with depth of experience in its observations and so generates a particular type of scalable findings. The effective export of ethnography into QI and safety research requires discussion and negotiation between social scientific and health services research perspectives, as well as creative approaches to producing self-reflexive data that will allow clinicians to understand their own context and so improve their own processes.

78 FR 13874 - Watershed Modeling To Assess the Sensitivity of Streamflow, Nutrient, and Sediment Loads to...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-01

... an improved understanding of methodological challenges associated with integrating existing tools and... methodological challenges associated with integrating existing tools (e.g., climate models, downscaling... sensitivity to methodological choices such as different approaches for downscaling global climate change...

A Simple and Universal Gel Permeation Chromatography Technique for Precise Molecular Weight Characterization of Well-Defined Poly(ionic liquid)s

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

He, Hongkun; Zhong, Mingjiang; Adzima, Brian

2013-03-20

Poly(ionic liquid)s (PILs) are an important class of technologically relevant materials. However, characterization of well-defined polyionic materials remains a challenge. Herein, we have developed a simple and versatile gel permeation chromatography (GPC) methodology for molecular weight (MW) characterization of PILs with a variety of anions. PILs with narrow MW distributions were synthesized via atom transfer radical polymerization, and the MWs obtained from GPC were further confirmed via nuclear magnetic resonance end group analysis.

Erosive lichen planus: a therapeutic challenge.

PubMed

Romero, Williams; Giesen, Laura; Navajas-Galimany, Lucas; Gonzalez, Sergio

2016-01-01

Erosive lichen planus is an uncommon variant of lichen planus. Chronic erosions of the soles, accompanied by intense and disabling pain, are some of its most characteristic manifestations. We present the case of a woman who developed oral and plantar erosive lichen planus associated with lichen planus pigmentosus and ungueal lichen planus that were diagnosed after several years. The patient failed to respond to multiple therapies requiring longstanding medication but remained refractory. Knowledge of the treatment options for erosive lichen planus is insufficient. Further research is required to clarify their effectiveness, ideally adopting an evidence-based methodology.

Toward Detection of Exoplanetary Rings via Transit Photometry: Methodology and a Possible Candidate

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

Aizawa, Masataka; Masuda, Kento; Suto, Yasushi

The detection of a planetary ring of exoplanets remains one of the most attractive, but challenging, goals in the field of exoplanetary science. We present a methodology that implements a systematic search for exoplanetary rings via transit photometry of long-period planets. This methodology relies on a precise integration scheme that we develop to compute a transit light curve of a ringed planet. We apply the methodology to 89 long-period planet candidates from the Kepler data so as to estimate, and/or set upper limits on, the parameters of possible rings. While the majority of our samples do not have sufficient signal-to-noise ratios (S/Ns) to place meaningfulmore » constraints on ring parameters, we find that six systems with higher S/Ns are inconsistent with the presence of a ring larger than 1.5 times the planetary radius, assuming a grazing orbit and a tilted ring. Furthermore, we identify five preliminary candidate systems whose light curves exhibit ring-like features. After removing four false positives due to the contamination from nearby stars, we identify KIC 10403228 as a reasonable candidate for a ringed planet. A systematic parameter fit of its light curve with a ringed planet model indicates two possible solutions corresponding to a Saturn-like planet with a tilted ring. There also remain two other possible scenarios accounting for the data; a circumstellar disk and a hierarchical triple. Due to large uncertain factors, we cannot choose one specific model among the three.« less

Online interviewing with interpreters in humanitarian contexts

PubMed Central

Chiumento, Anna; Rahman, Atif; Frith, Lucy

2018-01-01

ABSTRACT Purpose: Recognising that one way to address the logistical and safety considerations of research conducted in humanitarian emergencies is to use internet communication technologies to facilitate interviews online, this article explores some practical and methodological considerations inherent to qualitative online interviewing. Method: Reflections from a case study of a multi-site research project conducted in post-conflict countries are presented.  Synchronous online cross-language qualitative interviews were conducted in one country.  Although only a small proportion of interviews were conducted online (six out of 35), it remains important to critically consider the impact upon data produced in this way. Results: A range of practical and methodological considerations are discussed, illustrated with examples.  Results suggest that whilst online interviewing has methodological and ethical potential and versatility, there are inherent practical challenges in settings with poor internet and electricity infrastructure.  Notable methodological limitations include barriers to building rapport due to partial visual and non-visual cues, and difficulties interpreting pauses or silences. Conclusions: Drawing upon experiences in this case study, strategies for managing the practical and methodological limitations of online interviewing are suggested, alongside recommendations for supporting future research practice.  These are intended to act as a springboard for further reflection, and operate alongside other conceptual frameworks for online interviewing. PMID:29532739

Online interviewing with interpreters in humanitarian contexts.

PubMed

Chiumento, Anna; Machin, Laura; Rahman, Atif; Frith, Lucy

2018-12-01

Recognising that one way to address the logistical and safety considerations of research conducted in humanitarian emergencies is to use internet communication technologies to facilitate interviews online, this article explores some practical and methodological considerations inherent to qualitative online interviewing. Reflections from a case study of a multi-site research project conducted in post-conflict countries are presented.  Synchronous online cross-language qualitative interviews were conducted in one country.  Although only a small proportion of interviews were conducted online (six out of 35), it remains important to critically consider the impact upon data produced in this way. A range of practical and methodological considerations are discussed, illustrated with examples.  Results suggest that whilst online interviewing has methodological and ethical potential and versatility, there are inherent practical challenges in settings with poor internet and electricity infrastructure.  Notable methodological limitations include barriers to building rapport due to partial visual and non-visual cues, and difficulties interpreting pauses or silences. Drawing upon experiences in this case study, strategies for managing the practical and methodological limitations of online interviewing are suggested, alongside recommendations for supporting future research practice.  These are intended to act as a springboard for further reflection, and operate alongside other conceptual frameworks for online interviewing.

Conducting Research with LGB People of Color: Methodological Challenges and Strategies

ERIC Educational Resources Information Center

DeBlaere, Cirleen; Brewster, Melanie E.; Sarkees, Anthony; Moradi, Bonnie

2010-01-01

Methodological barriers have been highlighted as a primary reason for the limited research with lesbian, gay, and bisexual (LGB) people of color. Thus, strategies for anticipating and addressing potential methodological barriers are needed. To address this need, this article discusses potential challenges associated with conducting research with…

Glycoprotein Enrichment Analytical Techniques: Advantages and Disadvantages.

PubMed

Zhu, R; Zacharias, L; Wooding, K M; Peng, W; Mechref, Y

2017-01-01

Protein glycosylation is one of the most important posttranslational modifications. Numerous biological functions are related to protein glycosylation. However, analytical challenges remain in the glycoprotein analysis. To overcome the challenges associated with glycoprotein analysis, many analytical techniques were developed in recent years. Enrichment methods were used to improve the sensitivity of detection, while HPLC and mass spectrometry methods were developed to facilitate the separation of glycopeptides/proteins and enhance detection, respectively. Fragmentation techniques applied in modern mass spectrometers allow the structural interpretation of glycopeptides/proteins, while automated software tools started replacing manual processing to improve the reliability and throughput of the analysis. In this chapter, the current methodologies of glycoprotein analysis were discussed. Multiple analytical techniques are compared, and advantages and disadvantages of each technique are highlighted. © 2017 Elsevier Inc. All rights reserved.

CHAPTER 7: Glycoprotein Enrichment Analytical Techniques: Advantages and Disadvantages

PubMed Central

Zhu, Rui; Zacharias, Lauren; Wooding, Kerry M.; Peng, Wenjing; Mechref, Yehia

2017-01-01

Protein glycosylation is one of the most important posttranslational modifications. Numerous biological functions are related to protein glycosylation. However, analytical challenges remain in the glycoprotein analysis. To overcome the challenges associated with glycoprotein analysis, many analytical techniques were developed in recent years. Enrichment methods were used to improve the sensitivity of detection while HPLC and mass spectrometry methods were developed to facilitate the separation of glycopeptides/proteins and enhance detection, respectively. Fragmentation techniques applied in modern mass spectrometers allow the structural interpretation of glycopeptides/proteins while automated software tools started replacing manual processing to improve the reliability and throughout of the analysis. In this chapter, the current methodologies of glycoprotein analysis were discussed. Multiple analytical techniques are compared, and advantages and disadvantages of each technique are highlighted. PMID:28109440

Identifying associations between pig pathologies using a multi-dimensional machine learning methodology.

PubMed

Sanchez-Vazquez, Manuel J; Nielen, Mirjam; Edwards, Sandra A; Gunn, George J; Lewis, Fraser I

2012-08-31

Abattoir detected pathologies are of crucial importance to both pig production and food safety. Usually, more than one pathology coexist in a pig herd although it often remains unknown how these different pathologies interrelate to each other. Identification of the associations between different pathologies may facilitate an improved understanding of their underlying biological linkage, and support the veterinarians in encouraging control strategies aimed at reducing the prevalence of not just one, but two or more conditions simultaneously. Multi-dimensional machine learning methodology was used to identify associations between ten typical pathologies in 6485 batches of slaughtered finishing pigs, assisting the comprehension of their biological association. Pathologies potentially associated with septicaemia (e.g. pericarditis, peritonitis) appear interrelated, suggesting on-going bacterial challenges by pathogens such as Haemophilus parasuis and Streptococcus suis. Furthermore, hepatic scarring appears interrelated with both milk spot livers (Ascaris suum) and bacteria-related pathologies, suggesting a potential multi-pathogen nature for this pathology. The application of novel multi-dimensional machine learning methodology provided new insights into how typical pig pathologies are potentially interrelated at batch level. The methodology presented is a powerful exploratory tool to generate hypotheses, applicable to a wide range of studies in veterinary research.

Documenting Sociolinguistic Variation in Lesser-Studied Indigenous Communities: Challenges and Practical Solutions

ERIC Educational Resources Information Center

Mansfield, John; Stanford, James

2017-01-01

Documenting sociolinguistic variation in lesser-studied languages presents methodological challenges, but also offers important research opportunities. In this paper we examine three key methodological challenges commonly faced by researchers who are outsiders to the community. We then present practical solutions for successful variationist…

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

PubMed

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

2016-01-08

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

Liquid crystals of carbon nanotubes and graphene.

PubMed

Zakri, Cécile; Blanc, Christophe; Grelet, Eric; Zamora-Ledezma, Camilo; Puech, Nicolas; Anglaret, Eric; Poulin, Philippe

2013-04-13

Liquid crystal ordering is an opportunity to develop novel materials and applications with spontaneously aligned nanotubes or graphene particles. Nevertheless, achieving high orientational order parameter and large monodomains remains a challenge. In addition, our restricted knowledge of the structure of the currently available materials is a limitation for fundamental studies and future applications. This paper presents recent methodologies that have been developed to achieve large monodomains of nematic liquid crystals. These allow quantification and increase of their order parameters. Nematic ordering provides an efficient way to prepare conductive films that exhibit anisotropic properties. In particular, it is shown how the electrical conductivity anisotropy increases with the order parameter of the nematic liquid crystal. The order parameter can be tuned by controlling the length and entanglement of the nanotubes. In the second part of the paper, recent results on graphene liquid crystals are reported. The possibility to obtain water-based liquid crystals stabilized by surfactant molecules is demonstrated. Structural and thermodynamic characterizations provide indirect but statistical information on the dimensions of the graphene flakes. From a general point of view, this work presents experimental approaches to optimize the use of nanocarbons as liquid crystals and provides new methodologies for the still challenging characterization of such materials.

78 FR 68449 - Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-14

... RFA-HS14-002, Addressing Methodological Challenges in Research for Patients With Multiple Chronic... applications for the ``AHRQ RFA-HS14-002, Addressing Methodological Challenges in Research for Patients With...

Jumping genes: Genomic ballast or powerhouse of biological diversification.

PubMed

Choudhury, Rimjhim Roy; Parisod, Christian

2017-09-01

Studying hybridization has the potential to elucidate challenging questions in evolutionary biology such as the nature of adaptive genetic variation and reproductive isolation. A growing body of work highlights that the merging of divergent genomes goes beyond the reshuffling of standing variation from related species and promotes mutations (Abbott et al., ). However, to what extent such genome instability generates evolutionary significant variation remains largely elusive. In this issue of Molecular Ecology, Dennenmoser et al. () report considerable dynamics of transposable elements (TEs) in a recent invasive fish species of hybrid origin (Cottus; Figure ). It adds to the recent examples from plants to support TE-specific genome variation following hybridization. Insights from early, as well as established, hybrids are largely coherent with increased TE activity, and this fish system thus represents an inspiring opportunity to further address the possible association between genome dynamics and "rapid evolution of hybrid species." This work based on genome (re)sequencing contrasts with prior transcriptomics or PCR-based studies of TEs and illustrates how unprecedented amount of information promises a better understanding of the multiple patterns of variation across eukaryotic genomes; provided that we get the better of methodological advances. As discussed here, unbiased assessment of TE variation from genome surveys indeed remains a challenge precluding firm conclusions to be reached about the evolutionary significance of TEs. Despite methodological and conceptual developments that appear necessary to unambiguously uncover the unexplored iceberg below the known tip, the role of coding genes vs. TEs in promoting adaptation and speciation might be clarified in a not so remote future. © 2017 John Wiley & Sons Ltd.

A House Full of Trap Doors. Identifying barriers to resilient drylands in the toolbox of pastoral development

NASA Astrophysics Data System (ADS)

Krätli, Saverio; Kaufmann, Brigitte; Roba, Hassan; Hiernaux, Pierre; Li, Wenjun; Easdale, Marcos H.; Huelsebusch, Christian

2016-04-01

The theoretical understanding of drylands and pastoral systems has long undergone a U-turn from the initial perspective rooted in classical ecology. The shift has hinged on the way to represent asymmetric variability, from a disturbance in an ecosystem that naturally tends towards uniformity and stability, to a constitutive part of a dynamic ecosystem. Operationalising the new reversed perspective, including the need to update the methodological infrastructure to plan around drylands and pastoral development, remains a challenge. Underlying assumptions about stability and uniformity, that are a legacy of equilibrium thinking, remain embedded in the toolbox of pastoral development, starting from the technical language to talk about the subject. This effectively gets in the way of operationalizing state of the art understanding of pastoral systems and the drylands. Unless these barriers are identified, unpacked and managed, even the present calls for increasing the rigour and intensity of data collection - for example as part of the ongoing global process to revise and improve agricultural data - cannot deliver a realistic representation of pastoral systems in statistics and policy making. This contribution presents the case for understanding variability as an asset, and provides a range of examples of methodological barriers, including classifications of livestock systems, scale of observation, key parameters in animal production, indicators in the measurement of ecological efficiency, concepts of ecological fragility, natural resources, and pastoral risk. The need to update this legacy is a pressing challenge for policy makers concerned with both modernisation and resilience in the drylands.

Critical reflections on methodological challenge in arts and dementia evaluation and research.

PubMed

Gray, Karen; Evans, Simon Chester; Griffiths, Amanda; Schneider, Justine

2017-01-01

Methodological rigour, or its absence, is often a focus of concern for the emerging field of evaluation and research around arts and dementia. However, this paper suggests that critical attention should also be paid to the way in which individual perceptions, hidden assumptions and underlying social and political structures influence methodological work in the field. Such attention will be particularly important for addressing methodological challenges relating to contextual variability, ethics, value judgement and signification identified through a literature review on this topic. Understanding how, where and when evaluators and researchers experience such challenges may help to identify fruitful approaches for future evaluation.

Practical Issues of Conducting a Q Methodology Study: Lessons Learned From a Cross-cultural Study.

PubMed

Stone, Teresa Elizabeth; Maguire, Jane; Kang, Sook Jung; Cha, Chiyoung

This article advances nursing research by presenting the methodological challenges experienced in conducting a multination Q-methodology study. This article critically analyzes the relevance of the methodology for cross-cultural and nursing research and the challenges that led to specific responses by the investigators. The use of focus groups with key stakeholders supplemented the Q-analysis results. The authors discuss practical issues and shared innovative approaches and provide best-practice suggestions on the use of this flexible methodology. Q methodology has the versatility to explore complexities of contemporary nursing practice and cross-cultural health research.

Methodological development of the interactive INTERLINKS Framework for Long-term Care

PubMed Central

Billings, Jenny; Leichsenring, Kai

2014-01-01

There is increasing international research into health and social care services for older people in need of long-term care (LTC), but problems remain with respect to acquiring robust comparative information to enable judgements to be made regarding the most beneficial and cost-effective approaches. The project ‘INTERLINKS’ (‘Health systems and LTC for older people in Europe’) funded by the EU 7th Framework programme was developed to address the challenges associated with the accumulation and comparison of evidence in LTC across Europe. It developed a concept and method to describe and analyse LTC and its links with the health and social care system through the accumulation of policy and practice examples on an interactive web-based framework for LTC. This paper provides a critical overview of the theoretical and methodological approaches used to develop and implement the INTERLINKS Framework for LTC, with the aim of providing some guidance to researchers in this area. INTERLINKS has made a significant contribution to knowledge but robust evidence and comparability across European countries remain problematic due to the current and growing complexity and diversity of integrated LTC implementation. PMID:25120413

Concerns related to Safety Management of Engineered Nanomaterials in research environment

NASA Astrophysics Data System (ADS)

Groso, A.; Meyer, Th

2013-04-01

Since the rise of occupational safety and health research on nanomaterials a lot of progress has been made in generating health effects and exposure data. However, when detailed quantitative risk analysis is in question, more research is needed, especially quantitative measures of workers exposure and standards to categorize toxicity/hazardousness data. In the absence of dose-response relationships and quantitative exposure measurements, control banding (CB) has been widely adopted by OHS community as a pragmatic tool in implementing a risk management strategy based on a precautionary approach. Being in charge of health and safety in a Swiss university, where nanomaterials are largely used and produced, we are also faced with the challenge related to nanomaterials' occupational safety. In this work, we discuss the field application of an in-house risk management methodology similar to CB as well as some other methodologies. The challenges and issues related to the process will be discussed. Since exact data on nanomaterials hazardousness are missing for most of the situations, we deduce that the outcome of the analysis for a particular process is essentially the same with a simple methodology that determines only exposure potential and the one taking into account the hazardousness of ENPs. It is evident that when reliable data on hazardousness factors (as surface chemistry, solubility, carcinogenicity, toxicity etc.) will be available, more differentiation will be possible in determining the risk for different materials. On the protective measures side, all CB methodologies are inclined to overprotection side, only that some of them suggest comprehensive protective/preventive measures and others remain with basic advices. The implementation and control of protective measures in research environment will also be discussed.

Economic Evaluation of Adolescent Addiction Programs: Methodological Challenges and Recommendations

PubMed Central

Homer, Jenny F.; Drummond, Michael F.; French, Michael T.

2008-01-01

This paper identifies and describes several methodological challenges encountered in economic evaluations of substance abuse interventions for adolescents. Topics include study design, the choice of perspective, the estimation of costs and outcomes, and the generalizability of results. Recommendations are offered for confronting these challenges using examples from adolescent addiction research. PMID:19027640

Troubling the Boundaries: Overcoming Methodological Challenges in a Multi-Sectoral and Multi-Jurisdictional HIV/HCV Policy Scoping Review

ERIC Educational Resources Information Center

Hare, Kathleen A.; Dubé, Anik; Marshall, Zack; Gahagan, Jacqueline; Harris, Gregory E.; Tucker, Maryanne; Dykeman, Margaret; MacDonald, Jo-Ann

2016-01-01

Policy scoping reviews are an effective method for generating evidence-informed policies. However, when applying guiding methodological frameworks to complex policy evidence, numerous, unexpected challenges can emerge. This paper details five challenges experienced and addressed by a policy trainee-led, multi-disciplinary research team, while…

Empirically evaluating the impact of adjudicative tribunals in the health sector: context, challenges and opportunities.

PubMed

Hoffman, Steven J; Sossin, Lorne

2012-04-01

Adjudicative tribunals are an integral part of health system governance, yet their real-world impact remains largely unknown. Most assessments focus on internal accountability and use anecdotal methodologies; few, studies if any, empirically evaluate their external impact and use these data to test effectiveness, track performance, inform service improvements and ultimately strengthen health systems. Given that such assessments would yield important benefits and have been conducted successfully in similar settings (e.g. specialist courts), their absence is likely attributable to complexity in the health system, methodological difficulties and the legal environment within which tribunals operate. We suggest practical steps for potential evaluators to conduct empirical impact evaluations along with an evaluation matrix template featuring possible target outcomes and corresponding surrogate endpoints, performance indicators and empirical methodologies. Several system-level strategies for supporting such assessments have also been suggested for academics, health system institutions, health planners and research funders. Action is necessary to ensure that policymakers do not continue operating without evidence but can rather pursue data-driven strategies that are more likely to achieve their health system goals in a cost-effective way.

Using a Lean Six Sigma Approach to Yield Sustained Pressure Ulcer Prevention for Complex Critical Care Patients.

PubMed

Donovan, Elizabeth A; Manta, Christine J; Goldsack, Jennifer C; Collins, Michelle L

2016-01-01

Under value-based purchasing, Medicare withholds reimbursements for hospital-acquired pressure ulcer occurrence and rewards hospitals that meet performance standards. With little evidence of a validated prevention process, nurse managers are challenged to find evidence-based interventions. The aim of this study was to reduce the unit-acquired pressure ulcer (UAPU) rate on targeted intensive care and step-down units by 15% using Lean Six Sigma (LSS) methodology. An interdisciplinary team designed a pilot program using LSS methodology to test 4 interventions: standardized documentation, equipment monitoring, patient out-of-bed-to-chair monitoring, and a rounding checklist. During the pilot, the UAPU rate decreased from 4.4% to 2.8%, exceeding the goal of a 15% reduction. The rate remained below the goal through the program control phase at 2.9%, demonstrating a statistically significant reduction after intervention implementation. The program significantly reduced UAPU rates in high-risk populations. LSS methodologies are a sustainable approach to reducing hospital-acquired conditions that should be broadly tested and implemented.

Observational studies of the association between glucose-lowering medications and cardiovascular outcomes: addressing methodological limitations.

PubMed

Patorno, Elisabetta; Patrick, Amanda R; Garry, Elizabeth M; Schneeweiss, Sebastian; Gillet, Victoria G; Bartels, Dorothee B; Masso-Gonzalez, Elvira; Seeger, John D

2014-11-01

Recent years have witnessed a growing body of observational literature on the association between glucose-lowering treatments and cardiovascular disease. However, many of the studies are based on designs or analyses that inadequately address the methodological challenges involved. We reviewed recent observational literature on the association between glucose-lowering medications and cardiovascular outcomes and assessed the design and analysis methods used, with a focus on their ability to address specific methodological challenges. We describe and illustrate these methodological issues and their impact on observed associations, providing examples from the reviewed literature. We suggest approaches that may be employed to manage these methodological challenges. From the evaluation of 81 publications of observational investigations assessing the association between glucose-lowering treatments and cardiovascular outcomes, we identified the following methodological challenges: 1) handling of temporality in administrative databases; 2) handling of risks that vary with time and treatment duration; 3) definitions of the exposure risk window; 4) handling of exposures that change over time; and 5) handling of confounding by indication. Most of these methodological challenges may be suitably addressed through application of appropriate methods. Observational research plays an increasingly important role in the evaluation of the clinical effects of diabetes treatment. Implementation of appropriate research methods holds the promise of reducing the potential for spurious findings and the risk that the spurious findings will mislead the medical community about risks and benefits of diabetes medications.

Service Modeling Language Applied to Critical Infrastructure

NASA Astrophysics Data System (ADS)

Baldini, Gianmarco; Fovino, Igor Nai

The modeling of dependencies in complex infrastructure systems is still a very difficult task. Many methodologies have been proposed, but a number of challenges still remain, including the definition of the right level of abstraction, the presence of different views on the same critical infrastructure and how to adequately represent the temporal evolution of systems. We propose a modeling methodology where dependencies are described in terms of the service offered by the critical infrastructure and its components. The model provides a clear separation between services and the underlying organizational and technical elements, which may change in time. The model uses the Service Modeling Language proposed by the W3 consortium for describing critical infrastructure in terms of interdependent services nodes including constraints, behavior, information flows, relations, rules and other features. Each service node is characterized by its technological, organizational and process components. The model is then applied to a real case of an ICT system for users authentication.

Change IS Possible: Reducing High-Risk Drinking Using a Collaborative Improvement Model.

PubMed

Lanter, Patricia L; Wolff, Kristina B; Johnson, Lisa C; Ercolano, Ellyn M; Kilmer, Jason R; Provost, Lloyd

2015-01-01

To describe the adoption of public health and improvement methodologies to address college students' high-risk drinking behaviors and to aid in prevention efforts. Members of 32 colleges and universities, content experts, and staff members of the National College Health Improvement Program (NCHIP). A 2-year learning collaborative developed by NCHIP trained individuals from 32 different college and universities in using the Plan-Do-Study-Act cycle as a method to create and implement initiatives aimed at reducing students' high-risk drinking behaviors and related harms. Participants experienced success ranging from noteworthy increases in type and amount of interventions directed at reducing high-risk drinking, to creating collaboratives across campus, the local community, and stakeholders. Challenges related to data collection and creating lasting cultural change remain. The use of quality improvement methodologies and creation of a national collaborative successfully effected meaningful change in high-risk drinking behaviors on college campuses.

Operational challenges in delivering CD4 diagnostics in sub-Saharan Africa.

PubMed

Thairu, L; Katzenstein, D; Israelski, D

2011-07-01

Access to reliable and low cost CD4 T-cell enumeration to stage illness and monitor anti-retroviral therapy remains elusive in resource-limited settings. We report challenges in delivering CD4 testing using the microcapillary Fluorescence-Activated Cell Sorter (FACS) methodology (Guava EasyCD4 instrument Guava Technologies, Hayward) in Burkina Faso and Zimbabwe. Resources, instruments, reagents, and training were provided to local laboratories within the existing infrastructure and data on CD4 were collected from routine laboratory testing. Challenges encountered included frequent instrument breakdown; poor manufacturer maintenance; difficulties in managing reagent stocks; high technician turnover; reliance on antiquated data management systems; redundant service provision; and lack of repeat testing in male HIV+ patients and in patients with higher CD4 counts after initial staging. While adopting newer, less expensive technologies such as fluorescent platforms and point of care tests can facilitate access to lower cost CD4 testing, our experience suggests that supply chain, corporate commitment to implementation, and community factors also require consideration.

Opportunities and challenges for real-world studies on chronic inflammatory joint diseases through data enrichment and collaboration between national registers: the Nordic example

PubMed Central

Chatzidionysiou, Katerina; Hetland, Merete Lund; Frisell, Thomas; Di Giuseppe, Daniela; Hellgren, Karin; Glintborg, Bente; Nordström, Dan; Aaltonen, Kalle; Törmänen, Minna RK; Klami Kristianslund, Eirik; Kvien, Tore K; Provan, Sella A; Guðbjörnsson, Bjorn; Dreyer, Lene; Kristensen, Lars Erik; Jørgensen, Tanja Schjødt; Jacobsson, Lennart; Askling, Johan

2018-01-01

There are increasing needs for detailed real-world data on rheumatic diseases and their treatments. Clinical register data are essential sources of information that can be enriched through linkage to additional data sources such as national health data registers. Detailed analyses call for international collaborative observational research to increase the number of patients and the statistical power. Such linkages and collaborations come with legal, logistic and methodological challenges. In collaboration between registers of inflammatory arthritides in Sweden, Denmark, Norway, Finland and Iceland, we plan to enrich, harmonise and standardise individual data repositories to investigate analytical approaches to multisource data, to assess the viability of different logistical approaches to data protection and sharing and to perform collaborative studies on treatment effectiveness, safety and health-economic outcomes. This narrative review summarises the needs and potentials and the challenges that remain to be overcome in order to enable large-scale international collaborative research based on clinical and other types of data. PMID:29682328

Single-Case Experimental Designs: A Systematic Review of Published Research and Current Standards

PubMed Central

Smith, Justin D.

2013-01-01

This article systematically reviews the research design and methodological characteristics of single-case experimental design (SCED) research published in peer-reviewed journals between 2000 and 2010. SCEDs provide researchers with a flexible and viable alternative to group designs with large sample sizes. However, methodological challenges have precluded widespread implementation and acceptance of the SCED as a viable complementary methodology to the predominant group design. This article includes a description of the research design, measurement, and analysis domains distinctive to the SCED; a discussion of the results within the framework of contemporary standards and guidelines in the field; and a presentation of updated benchmarks for key characteristics (e.g., baseline sampling, method of analysis), and overall, it provides researchers and reviewers with a resource for conducting and evaluating SCED research. The results of the systematic review of 409 studies suggest that recently published SCED research is largely in accordance with contemporary criteria for experimental quality. Analytic method emerged as an area of discord. Comparison of the findings of this review with historical estimates of the use of statistical analysis indicates an upward trend, but visual analysis remains the most common analytic method and also garners the most support amongst those entities providing SCED standards. Although consensus exists along key dimensions of single-case research design and researchers appear to be practicing within these parameters, there remains a need for further evaluation of assessment and sampling techniques and data analytic methods. PMID:22845874

Economic Burden of Clostridium difficile Infection in European Countries.

PubMed

Reigadas Ramírez, Elena; Bouza, Emilio Santiago

2018-01-01

Clostridium difficile infection (CDI) remains a considerable challenge to health care systems worldwide. Although CDI represents a significant burden on healthcare systems in Europe, few studies have attempted to estimate the consumption of resources associated with CDI in Europe. The reported extra costs attributable to CDI vary widely according to the definitions, design, and methodologies used, making comparisons difficult to perform. In this chapter, the economic burden of healthcare facility-associated CDI in Europe will be assessed, as will other less explored areas such as the economic burden of recurrent CDI, community-acquired CDI, pediatric CDI, and CDI in outbreaks.

Pd-Catalyzed regioselective intramolecular dehydrogenative C-5 cross coupling in an N-substituted pyrrole-azole system.

PubMed

Tripathi, Krishna N; Ray, Devalina; Singh, Ravi P

2017-12-06

Functionalized polycyclic pyrrole-azole structures possessing fused six membered and seven membered rings were directly synthesized via ligand-enabled, Pd-catalyzed, site selective, intramolecular cross couplings of N-substituted pyrrole-azoles. C5-H activation in the presence of a reactive C2-H remains a challenge that needs to be addressed and this was targeted to be resolved through the present approach by specifically generating the cyclized products with 83-100% selectivity. The featured methodology provides a novel disconnection for the synthesis of pyrrole containing alkaloids and medicinal compounds.

Using artificial intelligence to bring evidence-based medicine a step closer to making the individual difference.

PubMed

Sissons, B; Gray, W A; Bater, A; Morrey, D

2007-03-01

The vision of evidence-based medicine is that of experienced clinicians systematically using the best research evidence to meet the individual patient's needs. This vision remains distant from clinical reality, as no complete methodology exists to apply objective, population-based research evidence to the needs of an individual real-world patient. We describe an approach, based on techniques from machine learning, to bridge this gap between evidence and individual patients in oncology. We examine existing proposals for tackling this gap and the relative benefits and challenges of our proposed, k-nearest-neighbour-based, approach.

Investigation into the efficacy of generating synthetic pathological oscillations for domain adaptation

NASA Astrophysics Data System (ADS)

Lewis, Rory; Ellenberger, James; Williams, Colton; White, Andrew M.

2013-11-01

In the ongoing investigation of integrating Knowledge Discovery in Databases (KDD) into neuroscience, we present a paper that facilitates overcoming the two challenges preventing this integration. Pathological oscillations found in the human brain are difficult to evaluate because 1) there is often no time to learn and train off of the same distribution in the fatally sick, and 2) sinusoidal signals found in the human brain are complex and transient in nature requiring large data sets to work with which are costly and often very expensive or impossible to acquire. Overcoming these challenges in today's neuro-intensive-care unit (ICU) requires insurmountable resources. For these reasons, optimizing KDD for pathological oscillations so machine learning systems can predict neuropathological states would be of immense value. Domain adaptation, which allows a way of predicting on a separate set of data than the training data, can theoretically overcome the first challenge. However, the challenge of acquiring large data sets that show whether domain adaptation is a good candidate to test in a live neuro ICU remains a challenge. To solve this conundrum, we present a methodology for generating synthesized neuropathological oscillations for domain adaptation.

Technology 2.0: A Commentary on Progress, Challenges, and Next Steps.

PubMed

Jones, Deborah J

2017-11-01

This commentary highlights the importance and promise of the innovative strategies described in the Child Maltreatment special issue on "Technology 2.0: A Focus on the Newest Technological Advances in Child Maltreatment Research." The commentary first highlights the collective advancements reflected in the articles in the special issue, with a primary focus on how the authors' work addresses a general challenge in services research that is perhaps nowhere more problematic than in the field of maltreatment. Next, the commentary extends the discussion of these articles to raise remaining gaps in our knowledge, theory, and methodology, which must be the focus of ongoing research if the true potential of technology as a service delivery vehicle is to be realized. Finally, the commentary concludes with a call for subsequent research which will be inspired by the articles in this special issue.

Speed-Accuracy Tradeoffs in Speech Production

DTIC Science & Technology

2017-06-01

imaging data of speech production. A theoretical framework for considering Fitts’ law in the domain of speech production is elucidated. Methodological ...articulatory kinematics conform to Fitts’ law. A second, associated goal is to address the methodological challenges inherent in performing Fitts-style...analysis on rtMRI data of speech production. Methodological challenges include segmenting continuous speech into specific motor tasks, defining key

Q methodology in health economics.

PubMed

Baker, Rachel; Thompson, Carl; Mannion, Russell

2006-01-01

The recognition that health economists need to understand the meaning of data if they are to adequately understand research findings which challenge conventional economic theory has led to the growth of qualitative modes of enquiry in health economics. The use of qualitative methods of exploration and description alongside quantitative techniques gives rise to a number of epistemological, ontological and methodological challenges: difficulties in accounting for subjectivity in choices, the need for rigour and transparency in method, and problems of disciplinary acceptability to health economists. Q methodology is introduced as a means of overcoming some of these challenges. We argue that Q offers a means of exploring subjectivity, beliefs and values while retaining the transparency, rigour and mathematical underpinnings of quantitative techniques. The various stages of Q methodological enquiry are outlined alongside potential areas of application in health economics, before discussing the strengths and limitations of the approach. We conclude that Q methodology is a useful addition to economists' methodological armoury and one that merits further consideration and evaluation in the study of health services.

Optimization of pyDock for the new CAPRI challenges: Docking of homology-based models, domain-domain assembly and protein-RNA binding.

PubMed

Pons, Carles; Solernou, Albert; Perez-Cano, Laura; Grosdidier, Solène; Fernandez-Recio, Juan

2010-11-15

We describe here our results in the last CAPRI edition. We have participated in all targets, both as predictors and as scorers, using our pyDock docking methodology. The new challenges (homology-based modeling of the interacting subunits, domain-domain assembling, and protein-RNA interactions) have pushed our computer tools to the limits and have encouraged us to devise new docking approaches. Overall, the results have been quite successful, in line with previous editions, especially considering the high difficulty of some of the targets. Our docking approaches succeeded in five targets as predictors or as scorers (T29, T34, T35, T41, and T42). Moreover, with the inclusion of available information on the residues expected to be involved in the interaction, our protocol would have also succeeded in two additional cases (T32 and T40). In the remaining targets (except T37), results were equally poor for most of the groups. We submitted the best model (in ligand RMSD) among scorers for the unbound-bound target T29, the second best model among scorers for the protein-RNA target T34, and the only correct model among predictors for the domain assembly target T35. In summary, our excellent results for the new proposed challenges in this CAPRI edition showed the limitations and applicability of our approaches and encouraged us to continue developing methodologies for automated biomolecular docking. © 2010 Wiley-Liss, Inc.

Test-treatment RCTs are susceptible to bias: a review of the methodological quality of randomized trials that evaluate diagnostic tests.

PubMed

Ferrante di Ruffano, Lavinia; Dinnes, Jacqueline; Sitch, Alice J; Hyde, Chris; Deeks, Jonathan J

2017-02-24

There is a growing recognition for the need to expand our evidence base for the clinical effectiveness of diagnostic tests. Many international bodies are calling for diagnostic randomized controlled trials to provide the most rigorous evidence of impact to patient health. Although these so-called test-treatment RCTs are very challenging to undertake due to their methodological complexity, they have not been subjected to a systematic appraisal of their methodological quality. The extent to which these trials may be producing biased results therefore remains unknown. We set out to address this issue by conducting a methodological review of published test-treatment trials to determine how often they implement adequate methods to limit bias and safeguard the validity of results. We ascertained all test-treatment RCTs published 2004-2007, indexed in CENTRAL, including RCTs which randomized patients to diagnostic tests and measured patient outcomes after treatment. Tests used for screening, monitoring or prognosis were excluded. We assessed adequacy of sequence generation, allocation concealment and intention-to-treat, appropriateness of primary analyses, blinding and reporting of power calculations, and extracted study characteristics including the primary outcome. One hundred three trials compared 105 control with 119 experimental interventions, and reported 150 primary outcomes. Randomization and allocation concealment were adequate in 57 and 37% of trials. Blinding was uncommon (patients 5%, clinicians 4%, outcome assessors 21%), as was an adequate intention-to-treat analysis (29%). Overall 101 of 103 trials (98%) were at risk of bias, as judged using standard Cochrane criteria. Test-treatment trials are particularly susceptible to attrition and inadequate primary analyses, lack of blinding and under-powering. These weaknesses pose much greater methodological and practical challenges to conducting reliable RCT evaluations of test-treatment strategies than standard treatment interventions. We suggest a cautious approach that first examines whether a test-treatment intervention can accommodate the methodological safeguards necessary to minimize bias, and highlight that test-treatment RCTs require different methods to ensure reliability than standard treatment trials. Please see the companion paper to this article: http://bmcmedresmethodol.biomedcentral.com/articles/10.1186/s12874-016-0286-0 .

Methodological Challenges in Studies Examining the Effects of Breakfast on Cognitive Performance and Appetite in Children and Adolescents.

PubMed

Adolphus, Katie; Bellissimo, Nick; Lawton, Clare L; Ford, Nikki A; Rains, Tia M; Totosy de Zepetnek, Julia; Dye, Louise

2017-01-01

Breakfast is purported to confer a number of benefits on diet quality, health, appetite regulation, and cognitive performance. However, new evidence has challenged the long-held belief that breakfast is the most important meal of the day. This review aims to provide a comprehensive discussion of the key methodological challenges and considerations in studies assessing the effect of breakfast on cognitive performance and appetite control, along with recommendations for future research. This review focuses on the myriad challenges involved in studying children and adolescents specifically. Key methodological challenges and considerations include study design and location, sampling and sample section, choice of objective cognitive tests, choice of objective and subjective appetite measures, merits of providing a fixed breakfast compared with ad libitum, assessment and definition of habitual breakfast consumption, transparency of treatment condition, difficulty of isolating the direct effects of breakfast consumption, untangling acute and chronic effects, and influence of confounding variables. These methodological challenges have hampered a clear substantiation of the potential positive effects of breakfast on cognition and appetite control and contributed to the debate questioning the notion that breakfast is the most important meal of the day. © 2017 American Society for Nutrition.

Methodological Challenges in Studies Examining the Effects of Breakfast on Cognitive Performance and Appetite in Children and Adolescents123

PubMed Central

Bellissimo, Nick; Ford, Nikki A; Rains, Tia M

2017-01-01

Breakfast is purported to confer a number of benefits on diet quality, health, appetite regulation, and cognitive performance. However, new evidence has challenged the long-held belief that breakfast is the most important meal of the day. This review aims to provide a comprehensive discussion of the key methodological challenges and considerations in studies assessing the effect of breakfast on cognitive performance and appetite control, along with recommendations for future research. This review focuses on the myriad challenges involved in studying children and adolescents specifically. Key methodological challenges and considerations include study design and location, sampling and sample section, choice of objective cognitive tests, choice of objective and subjective appetite measures, merits of providing a fixed breakfast compared with ad libitum, assessment and definition of habitual breakfast consumption, transparency of treatment condition, difficulty of isolating the direct effects of breakfast consumption, untangling acute and chronic effects, and influence of confounding variables. These methodological challenges have hampered a clear substantiation of the potential positive effects of breakfast on cognition and appetite control and contributed to the debate questioning the notion that breakfast is the most important meal of the day. PMID:28096143

Health Economics at the Crossroads of Centuries – From the Past to the Future

PubMed Central

Jakovljevic, Mihajlo (Michael); Ogura, Seiritsu

2016-01-01

Health economics, as an interdisciplinary science, has experienced exceptionally bold evolution through the past eight decades. Generations of committed scholars have built up huge body of knowledge and developed a set of methodological tools to assist health-care authorities with resource allocation process. Following its conception at the US National Bureau of Economic Research and Ivy League US Universities, this science has spread across the Globe. It has adapted to a myriad of local conditions and needs of the national health systems with diverse historical legacies, medical services provision, and financing patterns. Challenge of financial sustainability facing modern day health systems remains primarily attributable to population aging, prosperity diseases, large scale migrations, rapid urbanization, and technological innovation in medicine. Despite promising developments in developing countries with emerging BRICS markets on the lead, rising out-of-pocket health spending continues to threaten affordability of medical care. Universal health coverage extension will likely remain serious challenge even for some of the most advanced OECD nations. These complex circumstances create strong drivers for inevitable further development of health economics. We believe that this interdisciplinary health science shall leave long-lasting blue print to be visible for decades to come. PMID:27376055

Health Economics at the Crossroads of Centuries - From the Past to the Future.

PubMed

Jakovljevic, Mihajlo Michael; Ogura, Seiritsu

2016-01-01

Health economics, as an interdisciplinary science, has experienced exceptionally bold evolution through the past eight decades. Generations of committed scholars have built up huge body of knowledge and developed a set of methodological tools to assist health-care authorities with resource allocation process. Following its conception at the US National Bureau of Economic Research and Ivy League US Universities, this science has spread across the Globe. It has adapted to a myriad of local conditions and needs of the national health systems with diverse historical legacies, medical services provision, and financing patterns. Challenge of financial sustainability facing modern day health systems remains primarily attributable to population aging, prosperity diseases, large scale migrations, rapid urbanization, and technological innovation in medicine. Despite promising developments in developing countries with emerging BRICS markets on the lead, rising out-of-pocket health spending continues to threaten affordability of medical care. Universal health coverage extension will likely remain serious challenge even for some of the most advanced OECD nations. These complex circumstances create strong drivers for inevitable further development of health economics. We believe that this interdisciplinary health science shall leave long-lasting blue print to be visible for decades to come.

The Challenge of Timely, Responsive and Rigorous Ethics Review of Disaster Research: Views of Research Ethics Committee Members.

PubMed

Hunt, Matthew; Tansey, Catherine M; Anderson, James; Boulanger, Renaud F; Eckenwiler, Lisa; Pringle, John; Schwartz, Lisa

2016-01-01

Research conducted following natural disasters such as earthquakes, floods or hurricanes is crucial for improving relief interventions. Such research, however, poses ethical, methodological and logistical challenges for researchers. Oversight of disaster research also poses challenges for research ethics committees (RECs), in part due to the rapid turnaround needed to initiate research after a disaster. Currently, there is limited knowledge available about how RECs respond to and appraise disaster research. To address this knowledge gap, we investigated the experiences of REC members who had reviewed disaster research conducted in low- or middle-income countries. We used interpretive description methodology and conducted in-depth interviews with 15 respondents. Respondents were chairs, members, advisors, or coordinators from 13 RECs, including RECs affiliated with universities, governments, international organizations, a for-profit REC, and an ad hoc committee established during a disaster. Interviews were analyzed inductively using constant comparative techniques. Through this process, three elements were identified as characterizing effective and high-quality review: timeliness, responsiveness and rigorousness. To ensure timeliness, many RECs rely on adaptations of review procedures for urgent protocols. Respondents emphasized that responsive review requires awareness of and sensitivity to the particularities of disaster settings and disaster research. Rigorous review was linked with providing careful assessment of ethical considerations related to the research, as well as ensuring independence of the review process. Both the frequency of disasters and the conduct of disaster research are on the rise. Ensuring effective and high quality review of disaster research is crucial, yet challenges, including time pressures for urgent protocols, exist for achieving this goal. Adapting standard REC procedures may be necessary. However, steps should be taken to ensure that ethics review of disaster research remains diligent and thorough.

The Challenge of Timely, Responsive and Rigorous Ethics Review of Disaster Research: Views of Research Ethics Committee Members

PubMed Central

Hunt, Matthew; Tansey, Catherine M.

2016-01-01

Background Research conducted following natural disasters such as earthquakes, floods or hurricanes is crucial for improving relief interventions. Such research, however, poses ethical, methodological and logistical challenges for researchers. Oversight of disaster research also poses challenges for research ethics committees (RECs), in part due to the rapid turnaround needed to initiate research after a disaster. Currently, there is limited knowledge available about how RECs respond to and appraise disaster research. To address this knowledge gap, we investigated the experiences of REC members who had reviewed disaster research conducted in low- or middle-income countries. Methods We used interpretive description methodology and conducted in-depth interviews with 15 respondents. Respondents were chairs, members, advisors, or coordinators from 13 RECs, including RECs affiliated with universities, governments, international organizations, a for-profit REC, and an ad hoc committee established during a disaster. Interviews were analyzed inductively using constant comparative techniques. Results Through this process, three elements were identified as characterizing effective and high-quality review: timeliness, responsiveness and rigorousness. To ensure timeliness, many RECs rely on adaptations of review procedures for urgent protocols. Respondents emphasized that responsive review requires awareness of and sensitivity to the particularities of disaster settings and disaster research. Rigorous review was linked with providing careful assessment of ethical considerations related to the research, as well as ensuring independence of the review process. Conclusion Both the frequency of disasters and the conduct of disaster research are on the rise. Ensuring effective and high quality review of disaster research is crucial, yet challenges, including time pressures for urgent protocols, exist for achieving this goal. Adapting standard REC procedures may be necessary. However, steps should be taken to ensure that ethics review of disaster research remains diligent and thorough. PMID:27327165

Timely publication and sharing of trial data: opportunities and challenges for comparative effectiveness research in cardiovascular disease.

PubMed

Naci, Huseyin; Cooper, Jacob; Mossialos, Elias

2015-11-01

There is growing enthusiasm for the timely publication and sharing of clinical trial data. The rationale for open access includes greater transparency, reproducibility, and efficiency of the research enterprise. In cardiovascular diseases, routinely sharing clinical trial data would create opportunities for undertaking comparative effectiveness research, providing much needed evidence on how different interventions compare to each other on key outcomes. Access to individual patient-level data would strengthen the validity of such research. Novel methodological approaches like network meta-analyses using individual patient-level data could reliably compare interventions that have not been compared with each other in head-to-head trials. However, there are significant practical, methodological, financial, and legal challenges to this utopian open access that need to be continually addressed. Sharing clinical trial data openly will only occur when the previously tolerated process of clinical research involving direct ownership and secrecy is abandoned for a new culture in which medical science is open to all of its stakeholders. With this new culture, data will be accessible, reanalysis will be considered commonplace, and comparative effectiveness research through novel synthesis approaches, such as network meta-analyses, can thrive-as long as measures are taken to adequately ensure the goal remains to promote public health.

Assessing Daily Physical Activity in Older Adults: Unraveling the Complexity of Monitors, Measures, and Methods

PubMed Central

Cooper, Rachel; Koster, Annemarie; Shiroma, Eric J.; Murabito, Joanne M.; Rejeski, W. Jack; Ferrucci, Luigi; Harris, Tamara B.

2016-01-01

At the 67th Gerontological Society of America Annual Meeting, a preconference workshop was convened to discuss the challenges of accurately assessing physical activity in older populations. The advent of wearable technology (eg, accelerometers) to monitor physical activity has created unprecedented opportunities to observe, quantify, and define physical activity in the real-world setting. These devices enable researchers to better understand the associations of physical activity with aging, and subsequent health outcomes. However, a consensus on proper methodological use of these devices in older populations has not been established. To date, much of the validation research regarding device type, placement, and data interpretation has been performed in younger, healthier populations, and translation of these methods to older populations remains problematic. A better understanding of these devices, their measurement properties, and the data generated is imperative to furthering our understanding of daily physical activity, its effects on the aging process, and vice versa. The purpose of this article is to provide an overview of the highlights of the preconference workshop, including properties of the different types of accelerometers, the methodological challenges of employing accelerometers in older study populations, a brief summary of ongoing aging-related research projects that utilize different types of accelerometers, and recommendations for future research directions. PMID:26957472

Implications of the licensure of a partially efficacious malaria vaccine on evaluating second-generation vaccines.

PubMed

Fowkes, Freya J I; Simpson, Julie A; Beeson, James G

2013-10-30

Malaria is a leading cause of morbidity and mortality, with approximately 225 million clinical episodes and >1.2 million deaths annually attributed to malaria. Development of a highly efficacious malaria vaccine will offer unparalleled possibilities for disease prevention and remains a key priority for long-term malaria control and elimination. The Malaria Vaccine Technology Roadmap's goal is to 'develop and license a first-generation malaria vaccine that has protective efficacy of more than 50%'. To date, malaria vaccine candidates have only been shown to be partially efficacious (approximately 30% to 60%). However, licensure of a partially effective vaccine will create a number of challenges for the development and progression of new, potentially more efficacious, malaria vaccines in the future. In this opinion piece we discuss the methodological, logistical and ethical issues that may impact on the feasibility and implementation of superiority, non-inferiority and equivalence trials to assess second generation malaria vaccines in the advent of the licensure of a partially efficacious malaria vaccine. Selecting which new malaria vaccines go forward, and defining appropriate methodology for assessment in logistically challenging clinical trials, is crucial. It is imperative that the scientific community considers all the issues and starts planning how second-generation malaria vaccines will advance in the advent of licensure of a partially effective vaccine.

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

Kapil, Sanjay; Oberst, R. D.; Bieker, Jill Marie

Chemical disinfection and inactivation of viruses is largely understudied, but is very important especially in the case of highly infectious viruses. The purpose of this LDRD was to determine the efficacy of the Sandia National Laboratories developed decontamination formulations against Bovine Coronavirus (BCV) as a surrogate for the coronavirus that causes Severe Acute Respiratory Syndrome (SARS) in humans. The outbreak of SARS in late 2002 resulted from a highly infectious virus that was able to survive and remain infectious for extended periods. For this study, preliminary testing with Escherichia coli MS-2 (MS-2) and Escherichia coli T4 (T4) bacteriophages was conductedmore » to develop virucidal methodology for verifying the inactivation after treatment with the test formulations following AOAC germicidal methodologies. After the determination of various experimental parameters (i.e. exposure, concentration) of the formulations, final testing was conducted on BCV. All experiments were conducted with various organic challenges (horse serum, bovine feces, compost) for results that more accurately represent field use condition. The MS-2 and T4 were slightly more resistant than BCV and required a 2 minute exposure while BCV was completely inactivated after a 1 minute exposure. These results were also consistent for the testing conducted in the presence of the various organic challenges indicating that the test formulations are highly effective for real world application.« less

Toward a Multi-scale Phase Transition Kinetics Methodology: From Non-Equilibrium Statistical Mechanics to Hydrodynamics

NASA Astrophysics Data System (ADS)

Belof, Jonathan; Orlikowski, Daniel; Wu, Christine; McLaughlin, Keith

2013-06-01

Shock and ramp compression experiments are allowing us to probe condensed matter under extreme conditions where phase transitions and other non-equilibrium aspects can now be directly observed, but first principles simulation of kinetics remains a challenge. A multi-scale approach is presented here, with non-equilibrium statistical mechanical quantities calculated by molecular dynamics (MD) and then leveraged to inform a classical nucleation and growth kinetics model at the hydrodynamic scale. Of central interest is the free energy barrier for the formation of a critical nucleus, with direct NEMD presenting the challenge of relatively long timescales necessary to resolve nucleation. Rather than attempt to resolve the time-dependent nucleation sequence directly, the methodology derived here is built upon the non-equilibrium work theorem in order to bias the formation of a critical nucleus and thus construct the nucleation and growth rates. Having determined these kinetic terms from MD, a hydrodynamics implementation of Kolmogorov-Johnson-Mehl-Avrami (KJMA) kinetics and metastabilty is applied to the dynamic compressive freezing of water and compared with recent ramp compression experiments [Dolan et al., Nature (2007)] Lawrence Livermore National Laboratory is operated by Lawrence Livermore National Security, LLC, for the U.S. Department of Energy, National Nuclear Security Administration under Contract DE-AC52-07NA27344.

A state-of-the-art review on segmentation algorithms in intravascular ultrasound (IVUS) images.

PubMed

Katouzian, Amin; Angelini, Elsa D; Carlier, Stéphane G; Suri, Jasjit S; Navab, Nassir; Laine, Andrew F

2012-09-01

Over the past two decades, intravascular ultrasound (IVUS) image segmentation has remained a challenge for researchers while the use of this imaging modality is rapidly growing in catheterization procedures and in research studies. IVUS provides cross-sectional grayscale images of the arterial wall and the extent of atherosclerotic plaques with high spatial resolution in real time. In this paper, we review recently developed image processing methods for the detection of media-adventitia and luminal borders in IVUS images acquired with different transducers operating at frequencies ranging from 20 to 45 MHz. We discuss methodological challenges, lack of diversity in reported datasets, and weaknesses of quantification metrics that make IVUS segmentation still an open problem despite all efforts. In conclusion, we call for a common reference database, validation metrics, and ground-truth definition with which new and existing algorithms could be benchmarked.

Text mining for adverse drug events: the promise, challenges, and state of the art.

PubMed

Harpaz, Rave; Callahan, Alison; Tamang, Suzanne; Low, Yen; Odgers, David; Finlayson, Sam; Jung, Kenneth; LePendu, Paea; Shah, Nigam H

2014-10-01

Text mining is the computational process of extracting meaningful information from large amounts of unstructured text. It is emerging as a tool to leverage underutilized data sources that can improve pharmacovigilance, including the objective of adverse drug event (ADE) detection and assessment. This article provides an overview of recent advances in pharmacovigilance driven by the application of text mining, and discusses several data sources-such as biomedical literature, clinical narratives, product labeling, social media, and Web search logs-that are amenable to text mining for pharmacovigilance. Given the state of the art, it appears text mining can be applied to extract useful ADE-related information from multiple textual sources. Nonetheless, further research is required to address remaining technical challenges associated with the text mining methodologies, and to conclusively determine the relative contribution of each textual source to improving pharmacovigilance.

A Review of Hypothesized Determinants Associated with Bighorn Sheep (Ovis canadensis) Die-Offs

PubMed Central

Miller, David S.; Hoberg, Eric; Weiser, Glen; Aune, Keith; Atkinson, Mark; Kimberling, Cleon

2012-01-01

Multiple determinants have been hypothesized to cause or favor disease outbreaks among free-ranging bighorn sheep (Ovis canadensis) populations. This paper considered direct and indirect causes of mortality, as well as potential interactions among proposed environmental, host, and agent determinants of disease. A clear, invariant relationship between a single agent and field outbreaks has not yet been documented, in part due to methodological limitations and practical challenges associated with developing rigorous study designs. Therefore, although there is a need to develop predictive models for outbreaks and validated mitigation strategies, uncertainty remains as to whether outbreaks are due to endemic or recently introduced agents. Consequently, absence of established and universal explanations for outbreaks contributes to conflict among wildlife and livestock stakeholders over land use and management practices. This example illustrates the challenge of developing comprehensive models for understanding and managing wildlife diseases in complex biological and sociological environments. PMID:22567546

Text Mining for Adverse Drug Events: the Promise, Challenges, and State of the Art

PubMed Central

Harpaz, Rave; Callahan, Alison; Tamang, Suzanne; Low, Yen; Odgers, David; Finlayson, Sam; Jung, Kenneth; LePendu, Paea; Shah, Nigam H.

2014-01-01

Text mining is the computational process of extracting meaningful information from large amounts of unstructured text. Text mining is emerging as a tool to leverage underutilized data sources that can improve pharmacovigilance, including the objective of adverse drug event detection and assessment. This article provides an overview of recent advances in pharmacovigilance driven by the application of text mining, and discusses several data sources—such as biomedical literature, clinical narratives, product labeling, social media, and Web search logs—that are amenable to text-mining for pharmacovigilance. Given the state of the art, it appears text mining can be applied to extract useful ADE-related information from multiple textual sources. Nonetheless, further research is required to address remaining technical challenges associated with the text mining methodologies, and to conclusively determine the relative contribution of each textual source to improving pharmacovigilance. PMID:25151493

Environmental change challenges decision-making during post-market environmental monitoring of transgenic crops.

PubMed

Sanvido, Olivier; Romeis, Jörg; Bigler, Franz

2011-12-01

The ability to decide what kind of environmental changes observed during post-market environmental monitoring of genetically modified (GM) crops represent environmental harm is an essential part of most legal frameworks regulating the commercial release of GM crops into the environment. Among others, such decisions are necessary to initiate remedial measures or to sustain claims of redress linked to environmental liability. Given that consensus on criteria to evaluate 'environmental harm' has not yet been found, there are a number of challenges for risk managers when interpreting GM crop monitoring data for environmental decision-making. In the present paper, we argue that the challenges in decision-making have four main causes. The first three causes relate to scientific data collection and analysis, which have methodological limits. The forth cause concerns scientific data evaluation, which is controversial among the different stakeholders involved in the debate on potential impacts of GM crops on the environment. This results in controversy how the effects of GM crops should be valued and what constitutes environmental harm. This controversy may influence decision-making about triggering corrective actions by regulators. We analyse all four challenges and propose potential strategies for addressing them. We conclude that environmental monitoring has its limits in reducing uncertainties remaining from the environmental risk assessment prior to market approval. We argue that remaining uncertainties related to adverse environmental effects of GM crops would probably be assessed in a more efficient and rigorous way during pre-market risk assessment. Risk managers should acknowledge the limits of environmental monitoring programmes as a tool for decision-making.

Psychosocial development in racially and ethnically diverse youth: conceptual and methodological challenges in the 21st century.

PubMed

Swanson, Dena Phillips; Spencer, Margaret Beale; Harpalani, Vinay; Dupree, Davido; Noll, Elizabeth; Ginzburg, Sofia; Seaton, Gregory

2003-01-01

As the US population becomes more diverse in the 21st century, researchers face many conceptual and methodological challenges in working with diverse populations. We discuss these issues for racially and ethnically diverse youth, using Spencer's phenomenological variant of ecological systems theory (PVEST) as a guiding framework. We present a brief historical background and discuss recurring conceptual flaws in research on diverse youth, presenting PVEST as a corrective to these flaws. We highlight the interaction of race, culture, socioeconomic status, and various contexts of development with identity formation and other salient developmental processes. Challenges in research design and interpretation of data are also covered with regard to both assessment of contexts and developmental processes. We draw upon examples from neighborhood assessments, ethnic identity development, and attachment research to illustrate conceptual and methodological challenges, and we discuss strategies to address these challenges. The policy implications of our analysis are also considered.

Methodological strategies in using home sleep apnea testing in research and practice.

PubMed

Miller, Jennifer N; Schulz, Paula; Pozehl, Bunny; Fiedler, Douglas; Fial, Alissa; Berger, Ann M

2017-11-14

Home sleep apnea testing (HSAT) has increased due to improvements in technology, accessibility, and changes in third party reimbursement requirements. Research studies using HSAT have not consistently reported procedures and methodological challenges. This paper had two objectives: (1) summarize the literature on use of HSAT in research of adults and (2) identify methodological strategies to use in research and practice to standardize HSAT procedures and information. Search strategy included studies of participants undergoing sleep testing for OSA using HSAT. MEDLINE via PubMed, CINAHL, and Embase with the following search terms: "polysomnography," "home," "level III," "obstructive sleep apnea," and "out of center testing." Research articles that met inclusion criteria (n = 34) inconsistently reported methods and methodological challenges in terms of: (a) participant sampling; (b) instrumentation issues; (c) clinical variables; (d) data processing; and (e) patient acceptability. Ten methodological strategies were identified for adoption when using HSAT in research and practice. Future studies need to address the methodological challenges summarized in this paper as well as identify and report consistent HSAT procedures and information.

Methodological and ethical challenges in studying patients' perceptions of coercion: a systematic mixed studies review.

PubMed

Soininen, Päivi; Putkonen, Hanna; Joffe, Grigori; Korkeila, Jyrki; Välimäki, Maritta

2014-06-04

Despite improvements in psychiatric inpatient care, patient restrictions in psychiatric hospitals are still in use. Studying perceptions among patients who have been secluded or physically restrained during their hospital stay is challenging. We sought to review the methodological and ethical challenges in qualitative and quantitative studies aiming to describe patients' perceptions of coercive measures, especially seclusion and physical restraints during their hospital stay. Systematic mixed studies review was the study method. Studies reporting patients' perceptions of coercive measures, especially seclusion and physical restraints during hospital stay were included. Methodological issues such as study design, data collection and recruitment process, participants, sampling, patient refusal or non-participation, and ethical issues such as informed consent process, and approval were synthesized systematically. Electronic searches of CINALH, MEDLINE, PsychINFO and The Cochrane Library (1976-2012) were carried out. Out of 846 initial citations, 32 studies were included, 14 qualitative and 18 quantitative studies. A variety of methodological approaches were used, although descriptive and explorative designs were used in most cases. Data were mainly collected in qualitative studies by interviews (n = 13) or in quantitative studies by self-report questionnaires (n = 12). The recruitment process was explained in 59% (n = 19) of the studies. In most cases convenience sampling was used, yet five studies used randomization. Patient's refusal or non-participation was reported in 37% (n = 11) of studies. Of all studies, 56% (n = 18) had reported undergone an ethical review process in an official board or committee. Respondents were informed and consent was requested in 69% studies (n = 22). The use of different study designs made comparison methodologically challenging. The timing of data collection (considering bias and confounding factors) and the reasons for non-participation of eligible participants are likewise methodological challenges, e.g. recommended flow charts could aid the information. Other challenges identified were the recruitment of large and representative samples. Ethical challenges included requesting participants' informed consent and respecting ethical procedures.

Patient Derived Xenograft Models: An Emerging Platform for Translational Cancer Research

PubMed Central

Hidalgo, Manuel; Amant, Frederic; Biankin, Andrew V.; Budinská, Eva; Byrne, Annette T.; Caldas, Carlos; Clarke, Robert B.; de Jong, Steven; Jonkers, Jos; Mælandsmo, Gunhild Mari; Roman-Roman, Sergio; Seoane, Joan; Trusolino, Livio; Villanueva, Alberto

2014-01-01

Recently, there has been increasing interest in the development and characterization of patient derived tumor xenograft (PDX) models for cancer research. PDX models mostly retain the principal histological and genetic characteristics of their donor tumor and remain stable across passages. These models have been shown to be predictive of clinical outcomes and are being used for preclinical drug evaluation, biomarker identification, biological studies, and personalized medicine strategies. This paper summarizes the current state of the art in this field including methodological issues, available collections, practical applications, challenges and shortcoming, and future directions, and introduces a European consortium of PDX models. PMID:25185190

The dentist's care-taking perspective of dental fear patients - a continuous and changing challenge.

PubMed

Gyllensvärd, K; Qvarnström, M; Wolf, E

2016-08-01

The aim was to analyse the care taking of dental fear patients from the perspective of the dentist, using a qualitative methodology. In total, 11 dentists from both the private and public dental service were selected through a purposive sampling according to their experience of treating dental fear patients, their gender, age, service affiliation and location of undergraduate education. Data were obtained using one semi-structured interview with each informant. The interviews were taped and verbatim transcribed. The text was analysed using qualitative content analysis. The theme, 'The transforming autodidactic process of care taking', covering the interpretative level of data content was identified. The first main category covering the descriptive level of data was 'The continuous and changing challenge', with the subcategories 'The emotional demand' and 'The financial stress'. The second main category identified was 'The repeated collection of experience', with the subcategories 'The development of resources' and 'The emotional change'. The dentists' experience of treating dental fear patients was considered a challenging self-taught process under continuous transformation. The competence and routine platform expanded over time, parallel to a change of connected emotions from frustration towards safety, although challenges remained. © 2016 John Wiley & Sons Ltd.

Enzymatic browning in avocado (Persea americana) revisited: History, advances, and future perspectives.

PubMed

Toledo, Lea; Aguirre, Carolina

2017-12-12

Considering nearly 80 years of research regarding one of the enzymes responsible for catalyzing the formation of pigments in higher animals, plants, fungi and bacteria, this review will focus on collecting and categorizing the existing information about polyphenol oxidase (PPO) in fruits, with particular emphasis on the information in relation to avocado, which is one of the hardiest species in terms of inactivation, has documented dual activity (EC 1.14.18.1/EC 1.10.3.1), and represents one of the oldest challenges for food science research and fruit processors. It is expected that this review will contribute to the further development of the field by highlighting the questions that have arisen during the characterization of PPO, the progress that has been made and the questions that remain today, in addition to new methodologies that are being applied to study this system. Holistic methodologies offer unexplored potential for advancing our understanding of the complex phenomena that govern PPO activity in fruits, because these methodologies will enable the characterization of this family of enzymes in all of its complexity. Subsequently, it will be possible to develop better techniques for controlling enzymatic browning in this valuable fruit.

Reverse Engineering Validation using a Benchmark Synthetic Gene Circuit in Human Cells

PubMed Central

Kang, Taek; White, Jacob T.; Xie, Zhen; Benenson, Yaakov; Sontag, Eduardo; Bleris, Leonidas

2013-01-01

Multi-component biological networks are often understood incompletely, in large part due to the lack of reliable and robust methodologies for network reverse engineering and characterization. As a consequence, developing automated and rigorously validated methodologies for unraveling the complexity of biomolecular networks in human cells remains a central challenge to life scientists and engineers. Today, when it comes to experimental and analytical requirements, there exists a great deal of diversity in reverse engineering methods, which renders the independent validation and comparison of their predictive capabilities difficult. In this work we introduce an experimental platform customized for the development and verification of reverse engineering and pathway characterization algorithms in mammalian cells. Specifically, we stably integrate a synthetic gene network in human kidney cells and use it as a benchmark for validating reverse engineering methodologies. The network, which is orthogonal to endogenous cellular signaling, contains a small set of regulatory interactions that can be used to quantify the reconstruction performance. By performing successive perturbations to each modular component of the network and comparing protein and RNA measurements, we study the conditions under which we can reliably reconstruct the causal relationships of the integrated synthetic network. PMID:23654266

Reverse engineering validation using a benchmark synthetic gene circuit in human cells.

PubMed

Kang, Taek; White, Jacob T; Xie, Zhen; Benenson, Yaakov; Sontag, Eduardo; Bleris, Leonidas

2013-05-17

Multicomponent biological networks are often understood incompletely, in large part due to the lack of reliable and robust methodologies for network reverse engineering and characterization. As a consequence, developing automated and rigorously validated methodologies for unraveling the complexity of biomolecular networks in human cells remains a central challenge to life scientists and engineers. Today, when it comes to experimental and analytical requirements, there exists a great deal of diversity in reverse engineering methods, which renders the independent validation and comparison of their predictive capabilities difficult. In this work we introduce an experimental platform customized for the development and verification of reverse engineering and pathway characterization algorithms in mammalian cells. Specifically, we stably integrate a synthetic gene network in human kidney cells and use it as a benchmark for validating reverse engineering methodologies. The network, which is orthogonal to endogenous cellular signaling, contains a small set of regulatory interactions that can be used to quantify the reconstruction performance. By performing successive perturbations to each modular component of the network and comparing protein and RNA measurements, we study the conditions under which we can reliably reconstruct the causal relationships of the integrated synthetic network.

Speciation of adsorbates on surface of solids by infrared spectroscopy and chemometrics.

PubMed

Vilmin, Franck; Bazin, Philippe; Thibault-Starzyk, Frédéric; Travert, Arnaud

2015-09-03

Speciation, i.e. identification and quantification, of surface species on heterogeneous surfaces by infrared spectroscopy is important in many fields but remains a challenging task when facing strongly overlapped spectra of multiple adspecies. Here, we propose a new methodology, combining state of the art instrumental developments for quantitative infrared spectroscopy of adspecies and chemometrics tools, mainly a novel data processing algorithm, called SORB-MCR (SOft modeling by Recursive Based-Multivariate Curve Resolution) and multivariate calibration. After formal transposition of the general linear mixture model to adsorption spectral data, the main issues, i.e. validity of Beer-Lambert law and rank deficiency problems, are theoretically discussed. Then, the methodology is exposed through application to two case studies, each of them characterized by a specific type of rank deficiency: (i) speciation of physisorbed water species over a hydrated silica surface, and (ii) speciation (chemisorption and physisorption) of a silane probe molecule over a dehydrated silica surface. In both cases, we demonstrate the relevance of this approach which leads to a thorough surface speciation based on comprehensive and fully interpretable multivariate quantitative models. Limitations and drawbacks of the methodology are also underlined. Copyright © 2015 Elsevier B.V. All rights reserved.

Two Methodological Challenges for Teacher-Researchers: Reflexivity and Trustworthiness

ERIC Educational Resources Information Center

Xerri, Daniel

2018-01-01

Teacher research is lauded as a beneficial enterprise both for practitioners and for learners. However, teachers are sometimes accused of not possessing the necessary knowledge and skills to conduct research effectively. This article focuses on the need for teacher-researchers to find means of addressing the methodological challenges of engaging…

Counseling Psychology Research on Sexual (Orientation) Minority Issues: Conceptual and Methodological Challenges and Opportunities

ERIC Educational Resources Information Center

Moradi, Bonnie; Mohr, Jonathan J.; Worthington, Roger L.; Fassinger, Ruth E.

2009-01-01

This lead article of the special issue discusses conceptual and methodological considerations in studying sexual minority issues, particularly in research conducted by counseling psychologists (including the work represented in this special issue). First, the overarching challenge of conceptualizing and defining sexual minority populations is…

Theoretical Borderlands: Using Multiple Theoretical Perspectives to Challenge Inequitable Power Structures in Student Development Theory

ERIC Educational Resources Information Center

Abes, Elisa S.

2009-01-01

This article is an exploration of possibilities and methodological considerations for using multiple theoretical perspectives in research that challenges inequitable power structures in student development theory. Specifically, I explore methodological considerations when partnering queer theory and constructivism in research on lesbian identity…

Autoimmune encephalitis in children: clinical phenomenology, therapeutics, and emerging challenges.

PubMed

Dale, Russell C; Gorman, Mark P; Lim, Ming

2017-06-01

Auto-antibodies that bind to conformational extracellular epitopes of neuronal receptors or synaptic proteins have provided clinicians with essential biomarkers in acute neurology. This review summarizes the current status and challenges in the field. In children, anti-N-methyl-D-aspartate receptor encephalitis remains the most identifiable autoimmune encephalitis, although many patients have a clinical syndrome of brain inflammation in which no antibodies are identified. Anti-myelin oligodendrocyte glycoprotein antibody associated demyelination is now recognized as a major cause of monophasic and relapsing demyelination, often presenting with encephalopathy. We discuss the importance of auto-antibody detection methodology and the possible influence of intrathecal antibody synthesis on the speed of recovery and response to immune therapy. The current, often pragmatic rather than evidence-based therapeutic pathway will be discussed, highlighting key challenges such as the timing of second-line therapy, monitoring of disease activity, and identifying the patient who is responding poorly to treatment. Although there have been significant developments, future priorities include the need for paediatric-specific consensus definitions for seronegative suspected autoimmune encephalitis, novel tools for monitoring patients with autoimmune encephalitis, consensus treatment recommendations, and neuroprotective strategies.

Unpacking team process dynamics and emergent phenomena: Challenges, conceptual advances, and innovative methods.

PubMed

Kozlowski, Steve W J; Chao, Georgia T

2018-01-01

Psychologists have studied small-group and team effectiveness for decades, and although there has been considerable progress, there remain significant challenges. Meta-analyses and systematic research have provided solid evidence for core team cognitive, motivational, affective, and behavioral processes that contribute to team effectiveness and empirical support for interventions that enhance team processes (e.g., team design, composition, training, and leadership); there has been substantial evidence for a science of team effectiveness. Nonetheless, there have also been concerns that team processes, which are inherently dynamic, have primarily been assessed as static constructs. Team-level processes and outcomes are multilevel phenomena that emerge, bottom-up from the interactions among team members over time, under the shifting demands of a work context. Thus, theoretical development that appropriately conceptualizes the multiple levels, process dynamics, and emergence of team phenomena over time are essential to advance understanding. Moreover, these conceptual advances necessitate innovative research methodologies to better capture team process dynamics. We explicate this foundation and then describe 2 promising streams of scientific inquiry-team interaction sensors and computational modeling-that are advancing new, unobtrusive measurement techniques and process-oriented research methods focused on understanding the dynamics of cohesion and cognition in teamwork. These are distinct lines of research, each endeavoring to advance the science, but doing so through the development of very different methodologies. We close by discussing the near-term research challenges and the potential long-term evolution of these innovative methods, with an eye toward the future for process-oriented theory and research on team effectiveness. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

['Walkability' and physical activity - results of empirical studies based on the 'Neighbourhood Environment Walkability Scale (NEWS)'].

PubMed

Rottmann, M; Mielck, A

2014-02-01

'Walkability' is mainly assessed by the NEWS questionnaire (Neighbourhood Environment Walkability Scale); in Germany this questionnaire is widely unknown. We now try to fill this gap by providing a systematic overview of empirical studies based on the NEWS. A systematic review was conducted concerning original papers including empirical analyses based on the NEWS. The results are summarised and presented in tables. Altogether 31 publications could be identified. Most of them focus on associations with the variable 'physical activity', and they often report significant associations with at least some of the scales included in the NEWS. Due to methodological differences between the studies it is difficult to compare the results. The concept of 'walkability' should also be established in the German public health discussion. A number of methodological challenges remain to be solved, such as the identification of those scales and items in the NEWS that show the strongest associations with individual health behaviours. © Georg Thieme Verlag KG Stuttgart · New York.

Bioinspired Methodology for Artificial Olfaction

PubMed Central

Raman, Baranidharan; Hertz, Joshua L.; Benkstein, Kurt D.; Semancik, Steve

2008-01-01

Artificial olfaction is a potential tool for noninvasive chemical monitoring. Application of “electronic noses” typically involves recognition of “pretrained” chemicals, while long-term operation and generalization of training to allow chemical classification of “unknown” analytes remain challenges. The latter analytical capability is critically important, as it is unfeasible to pre-expose the sensor to every analyte it might encounter. Here, we demonstrate a biologically inspired approach where the recognition and generalization problems are decoupled and resolved in a hierarchical fashion. Analyte composition is refined in a progression from general (e.g., target is a hydrocarbon) to precise (e.g., target is ethane), using highly optimized response features for each step. We validate this approach using a MEMS-based chemiresistive microsensor array. We show that this approach, a unique departure from existing methodologies in artificial olfaction, allows the recognition module to better mitigate sensor-aging effects and to better classify unknowns, enhancing the utility of chemical sensors for real-world applications. PMID:18855409

Multi-Dielectric Brownian Dynamics and Design-Space-Exploration Studies of Permeation in Ion Channels.

PubMed

Siksik, May; Krishnamurthy, Vikram

2017-09-01

This paper proposes a multi-dielectric Brownian dynamics simulation framework for design-space-exploration (DSE) studies of ion-channel permeation. The goal of such DSE studies is to estimate the channel modeling-parameters that minimize the mean-squared error between the simulated and expected "permeation characteristics." To address this computational challenge, we use a methodology based on statistical inference that utilizes the knowledge of channel structure to prune the design space. We demonstrate the proposed framework and DSE methodology using a case study based on the KcsA ion channel, in which the design space is successfully reduced from a 6-D space to a 2-D space. Our results show that the channel dielectric map computed using the framework matches with that computed directly using molecular dynamics with an error of 7%. Finally, the scalability and resolution of the model used are explored, and it is shown that the memory requirements needed for DSE remain constant as the number of parameters (degree of heterogeneity) increases.

AIM - Agile Instrumented Monitoring for Improving User Experience of Participation in HealthIT Development.

PubMed

Pitkänen, Janne; Nieminen, Marko

2017-01-01

Participation of healthcare professionals in information technology development has emerged as an important challenge. As end-users, the professionals are willing to participate in the development activities, but their experiences on the current methods of participation remain mostly negative. There is lack of applicable methods for meeting the needs of agile development approach and scaling up to the largest implementation projects, while maintaining the interest of the professional users to participate in development activities and keeping up their ability to continue working in a productive manner. In this paper, we describe the Agile Instrumented Monitoring as a methodology, based on the methods of instrumented usability evaluation, for improving user experience in HealthIT development. The contribution of the proposed methodology is analyzed in relation to activities of whole iteration cycle and chosen usability evaluation methods, while the user experience of participation is addressed regarding healthcare professionals. Prospective weak and strong market tests for AIM are discussed in the conclusions for future work.

Gait Partitioning Methods: A Systematic Review

PubMed Central

Taborri, Juri; Palermo, Eduardo; Rossi, Stefano; Cappa, Paolo

2016-01-01

In the last years, gait phase partitioning has come to be a challenging research topic due to its impact on several applications related to gait technologies. A variety of sensors can be used to feed algorithms for gait phase partitioning, mainly classifiable as wearable or non-wearable. Among wearable sensors, footswitches or foot pressure insoles are generally considered as the gold standard; however, to overcome some inherent limitations of the former, inertial measurement units have become popular in recent decades. Valuable results have been achieved also though electromyography, electroneurography, and ultrasonic sensors. Non-wearable sensors, such as opto-electronic systems along with force platforms, remain the most accurate system to perform gait analysis in an indoor environment. In the present paper we identify, select, and categorize the available methodologies for gait phase detection, analyzing advantages and disadvantages of each solution. Finally, we comparatively examine the obtainable gait phase granularities, the usable computational methodologies and the optimal sensor placements on the targeted body segments. PMID:26751449

Gait Partitioning Methods: A Systematic Review.

PubMed

Taborri, Juri; Palermo, Eduardo; Rossi, Stefano; Cappa, Paolo

2016-01-06

In the last years, gait phase partitioning has come to be a challenging research topic due to its impact on several applications related to gait technologies. A variety of sensors can be used to feed algorithms for gait phase partitioning, mainly classifiable as wearable or non-wearable. Among wearable sensors, footswitches or foot pressure insoles are generally considered as the gold standard; however, to overcome some inherent limitations of the former, inertial measurement units have become popular in recent decades. Valuable results have been achieved also though electromyography, electroneurography, and ultrasonic sensors. Non-wearable sensors, such as opto-electronic systems along with force platforms, remain the most accurate system to perform gait analysis in an indoor environment. In the present paper we identify, select, and categorize the available methodologies for gait phase detection, analyzing advantages and disadvantages of each solution. Finally, we comparatively examine the obtainable gait phase granularities, the usable computational methodologies and the optimal sensor placements on the targeted body segments.

Methodological approach and tools for systems thinking in health systems research: technical assistants' support of health administration reform in the Democratic Republic of Congo as an application.

PubMed

Ribesse, Nathalie; Bossyns, Paul; Marchal, Bruno; Karemere, Hermes; Burman, Christopher J; Macq, Jean

2017-03-01

In the field of development cooperation, interest in systems thinking and complex systems theories as a methodological approach is increasingly recognised. And so it is in health systems research, which informs health development aid interventions. However, practical applications remain scarce to date. The objective of this article is to contribute to the body of knowledge by presenting the tools inspired by systems thinking and complexity theories and methodological lessons learned from their application. These tools were used in a case study. Detailed results of this study are in process for publication in additional articles. Applying a complexity 'lens', the subject of the case study is the role of long-term international technical assistance in supporting health administration reform at the provincial level in the Democratic Republic of Congo. The Methods section presents the guiding principles of systems thinking and complex systems, their relevance and implication for the subject under study, and the existing tools associated with those theories which inspired us in the design of the data collection and analysis process. The tools and their application processes are presented in the results section, and followed in the discussion section by the critical analysis of their innovative potential and emergent challenges. The overall methodology provides a coherent whole, each tool bringing a different and complementary perspective on the system.

BTC method for evaluation of remaining strength and service life of bridge cables.

DOT National Transportation Integrated Search

2011-09-01

"This report presents the BTC method; a comprehensive state-of-the-art methodology for evaluation of remaining : strength and residual life of bridge cables. The BTC method is a probability-based, proprietary, patented, and peerreviewed : methodology...

Heterogeneous Effects in Education: The Promise and Challenge of Incorporating Intersectionality into Quantitative Methodological Approaches

ERIC Educational Resources Information Center

Schudde, Lauren

2018-01-01

To date, the theory of intersectionality has largely guided qualitative efforts in social science and education research. Translating the construct to new methodological approaches is inherently complex and challenging, but offers the possibility of breaking down silos that keep education researchers with similar interests--but different…

The Challenges to and the Need for International Research in Educational Leadership

ERIC Educational Resources Information Center

Brooks, Melanie Carol; Jean-Marie, Gaetane

2015-01-01

Purpose: The purpose of this paper is twofold: to discuss methodological challenges facing US scholars when conducting international research; and to present personal reflections as educational leadership faculty in the USA conducting and publishing on research undertaken in Haiti and Thailand. Design/Methodology/Approach: This study drew from…

The Challenge of Researching Violent Societies: Navigating Complexities in Ethnography

ERIC Educational Resources Information Center

Tshabangu, Icarbord

2009-01-01

Through use of a recent study researching democratic education and citizenship in Zimbabwe, this paper examines the methodological dilemmas and challenges faced by an ethnographer, particularly by a research student in a violent context. The article posits a bricolage strategy to navigate some of the dangers and methodological dilemmas inherent so…

Queering Methodologies: Challenging Scientific Constraint in the Appreciation of Queer and Trans Subjects

ERIC Educational Resources Information Center

Ferguson, Joshua M.

2013-01-01

Qualitative studies require a queer perspective to challenge stagnant forms of scientific discourse. This paper argues for a deconstruction of hegemonic qualitative practices in order to appreciate and listen to queer and trans subjects when employing qualitative research and methodologies. I focus on qualitative methods from an audiovisual…

Measuring Cognitive and Metacognitive Regulatory Processes during Hypermedia Learning: Issues and Challenges

ERIC Educational Resources Information Center

Azevedo, Roger; Moos, Daniel C.; Johnson, Amy M.; Chauncey, Amber D.

2010-01-01

Self-regulated learning (SRL) with hypermedia environments involves a complex cycle of temporally unfolding cognitive and metacognitive processes that impact students' learning. We present several methodological issues related to treating SRL as an event and strengths and challenges of using online trace methodologies to detect, trace, model, and…

The Psychological Study of Video Game Players: Methodological Challenges and Practical Advice

ERIC Educational Resources Information Center

King, Daniel; Delfabbro, Paul; Griffiths, Mark

2009-01-01

Video game playing has received increased academic interest over the last few decades, particularly with regard to the psychological understanding of addiction. Based on the many studies carried out by the authors, this paper summarises some of the methodological challenges which may arise when studying video game players, including obstacles…

Tough Teens: The Methodological Challenges of Interviewing Teenagers as Research Participants

ERIC Educational Resources Information Center

Bassett, Raewyn; Beagan, Brenda L.; Ristovski-Slijepcevic, Svetlana; Chapman, Gwen E.

2008-01-01

Encouraging a teenager to have a conversation in a semistructured research interview is fraught with difficulties. The authors discuss the methodological challenges encountered when interviewing adolescents of European Canadian, African Canadian, and Punjabi Canadian families who took part in the Family Food Decision-Making Study in two regions of…

Abundance and Distribution of Enteric Bacteria and Viruses in Coastal and Estuarine Sediments—a Review

PubMed Central

Hassard, Francis; Gwyther, Ceri L.; Farkas, Kata; Andrews, Anthony; Jones, Vera; Cox, Brian; Brett, Howard; Jones, Davey L.; McDonald, James E.; Malham, Shelagh K.

2016-01-01

The long term survival of fecal indicator organisms (FIOs) and human pathogenic microorganisms in sediments is important from a water quality, human health and ecological perspective. Typically, both bacteria and viruses strongly associate with particulate matter present in freshwater, estuarine and marine environments. This association tends to be stronger in finer textured sediments and is strongly influenced by the type and quantity of clay minerals and organic matter present. Binding to particle surfaces promotes the persistence of bacteria in the environment by offering physical and chemical protection from biotic and abiotic stresses. How bacterial and viral viability and pathogenicity is influenced by surface attachment requires further study. Typically, long-term association with surfaces including sediments induces bacteria to enter a viable-but-non-culturable (VBNC) state. Inherent methodological challenges of quantifying VBNC bacteria may lead to the frequent under-reporting of their abundance in sediments. The implications of this in a quantitative risk assessment context remain unclear. Similarly, sediments can harbor significant amounts of enteric viruses, however, the factors regulating their persistence remains poorly understood. Quantification of viruses in sediment remains problematic due to our poor ability to recover intact viral particles from sediment surfaces (typically <10%), our inability to distinguish between infective and damaged (non-infective) viral particles, aggregation of viral particles, and inhibition during qPCR. This suggests that the true viral titre in sediments may be being vastly underestimated. In turn, this is limiting our ability to understand the fate and transport of viruses in sediments. Model systems (e.g., human cell culture) are also lacking for some key viruses, preventing our ability to evaluate the infectivity of viruses recovered from sediments (e.g., norovirus). The release of particle-bound bacteria and viruses into the water column during sediment resuspension also represents a risk to water quality. In conclusion, our poor process level understanding of viral/bacterial-sediment interactions combined with methodological challenges is limiting the accurate source apportionment and quantitative microbial risk assessment for pathogenic organisms associated with sediments in aquatic environments. PMID:27847499

Why European and United States drug regulators are not speaking with one voice on anti-influenza drugs: regulatory review methodologies and the importance of 'deep' product reviews.

PubMed

Mulinari, Shai; Davis, Courtney

2017-11-09

Relenza represents the first neuraminidase inhibitor (NI), a class of drugs that also includes the drug Tamiflu. Although heralded as breakthrough treatments in influenza, NI efficacy has remained highly controversial. A key unsettled question is why the United States Food and Drug Administration (FDA) has approved more cautious efficacy statements in labelling than European regulators for both drugs. We conducted a qualitative analysis of United States and European Union regulatory appraisals for Relenza to investigate the reasons for divergent regulatory interpretations, pertaining to Relenza's capacity to alleviate symptoms and reduce frequency of complications of influenza. In Europe, Relenza was evaluated via the so-called national procedure with Sweden as the reference country. We show that FDA reviewers, unlike their European (i.e. Swedish) counterpart, (1) rejected the manufacturer's insistence on pooling efficacy data, (2) remained wary of subgroup analyses, and (3) insisted on stringent statistical analyses. These differences meant that the FDA was less likely to depart from prevailing regulatory and scientific standards in interpreting trial results. We argue that the differences are explained largely by divergent institutionalised review methodologies, i.e. the European regulator's reliance on manufacturer-compiled summaries compared to the FDA's examination of original data and documentation from trials. The FDA's more probing and meticulous evaluative methodology allowed its reviewers to develop 'deep' knowledge concerning the clinical and statistical facets of trials, and more informed opinions regarding suitable methods for analysing trial results. These findings challenge the current emphasis on evaluating regulatory performance mainly in terms of speed of review. We propose that persistent uncertainty and knowledge deficits regarding NIs could have been ameliorated had regulators engaged in the public debates over the drugs' efficacy and explained their contrasting methodologies and judgments. Regulators use major resources to evaluate drugs, but if regulators' assessments are not effectively disseminated and used, resources are used inefficiently.

Defining Exercise Performance Metrics for Flight Hardware Development

NASA Technical Reports Server (NTRS)

Beyene, Nahon M.

2004-01-01

The space industry has prevailed over numerous design challenges in the spirit of exploration. Manned space flight entails creating products for use by humans and the Johnson Space Center has pioneered this effort as NASA's center for manned space flight. NASA Astronauts use a suite of flight exercise hardware to maintain strength for extravehicular activities and to minimize losses in muscle mass and bone mineral density. With a cycle ergometer, treadmill, and the Resistive Exercise Device available on the International Space Station (ISS), the Space Medicine community aspires to reproduce physical loading schemes that match exercise performance in Earth s gravity. The resistive exercise device presents the greatest challenge with the duty of accommodating 20 different exercises and many variations on the core set of exercises. This paper presents a methodology for capturing engineering parameters that can quantify proper resistive exercise performance techniques. For each specified exercise, the method provides engineering parameters on hand spacing, foot spacing, and positions of the point of load application at the starting point, midpoint, and end point of the exercise. As humans vary in height and fitness levels, the methodology presents values as ranges. In addition, this method shows engineers the proper load application regions on the human body. The methodology applies to resistive exercise in general and is in use for the current development of a Resistive Exercise Device. Exercise hardware systems must remain available for use and conducive to proper exercise performance as a contributor to mission success. The astronauts depend on exercise hardware to support extended stays aboard the ISS. Future plans towards exploration of Mars and beyond acknowledge the necessity of exercise. Continuous improvement in technology and our understanding of human health maintenance in space will allow us to support the exploration of Mars and the future of space exploration.

From theory to 'measurement' in complex interventions: methodological lessons from the development of an e-health normalisation instrument.

PubMed

Finch, Tracy L; Mair, Frances S; O'Donnell, Catherine; Murray, Elizabeth; May, Carl R

2012-05-17

Although empirical and theoretical understanding of processes of implementation in health care is advancing, translation of theory into structured measures that capture the complex interplay between interventions, individuals and context remain limited. This paper aimed to (1) describe the process and outcome of a project to develop a theory-based instrument for measuring implementation processes relating to e-health interventions; and (2) identify key issues and methodological challenges for advancing work in this field. A 30-item instrument (Technology Adoption Readiness Scale (TARS)) for measuring normalisation processes in the context of e-health service interventions was developed on the basis on Normalization Process Theory (NPT). NPT focuses on how new practices become routinely embedded within social contexts. The instrument was pre-tested in two health care settings in which e-health (electronic facilitation of healthcare decision-making and practice) was used by health care professionals. The developed instrument was pre-tested in two professional samples (N=46; N=231). Ratings of items representing normalisation 'processes' were significantly related to staff members' perceptions of whether or not e-health had become 'routine'. Key methodological challenges are discussed in relation to: translating multi-component theoretical constructs into simple questions; developing and choosing appropriate outcome measures; conducting multiple-stakeholder assessments; instrument and question framing; and more general issues for instrument development in practice contexts. To develop theory-derived measures of implementation process for progressing research in this field, four key recommendations are made relating to (1) greater attention to underlying theoretical assumptions and extent of translation work required; (2) the need for appropriate but flexible approaches to outcomes measurement; (3) representation of multiple perspectives and collaborative nature of work; and (4) emphasis on generic measurement approaches that can be flexibly tailored to particular contexts of study.

Recent Advances in Resting-State Electroencephalography Biomarkers for Autism Spectrum Disorder-A Review of Methodological and Clinical Challenges.

PubMed

Heunis, Tosca-Marie; Aldrich, Chris; de Vries, Petrus J

2016-08-01

Electroencephalography (EEG) has been used for almost a century to identify seizure-related disorders in humans, typically through expert interpretation of multichannel recordings. Attempts have been made to quantify EEG through frequency analyses and graphic representations. These "traditional" quantitative EEG analysis methods were limited in their ability to analyze complex and multivariate data and have not been generally accepted in clinical settings. There has been growing interest in identification of novel EEG biomarkers to detect early risk of autism spectrum disorder, to identify clinically meaningful subgroups, and to monitor targeted intervention strategies. Most studies to date have, however, used quantitative EEG approaches, and little is known about the emerging multivariate analytical methods or the robustness of candidate biomarkers in the context of the variability of autism spectrum disorder. Here, we present a targeted review of methodological and clinical challenges in the search for novel resting-state EEG biomarkers for autism spectrum disorder. Three primary novel methodologies are discussed: (1) modified multiscale entropy, (2) coherence analysis, and (3) recurrence quantification analysis. Results suggest that these methods may be able to classify resting-state EEG as "autism spectrum disorder" or "typically developing", but many signal processing questions remain unanswered. We suggest that the move to novel EEG analysis methods is akin to the progress in neuroimaging from visual inspection, through region-of-interest analysis, to whole-brain computational analysis. Novel resting-state EEG biomarkers will have to evaluate a range of potential demographic, clinical, and technical confounders including age, gender, intellectual ability, comorbidity, and medication, before these approaches can be translated into the clinical setting. Copyright © 2016 Elsevier Inc. All rights reserved.

Global inverse modeling of CH4 sources and sinks: an overview of methods

NASA Astrophysics Data System (ADS)

Houweling, Sander; Bergamaschi, Peter; Chevallier, Frederic; Heimann, Martin; Kaminski, Thomas; Krol, Maarten; Michalak, Anna M.; Patra, Prabir

2017-01-01

The aim of this paper is to present an overview of inverse modeling methods that have been developed over the years for estimating the global sources and sinks of CH4. It provides insight into how techniques and estimates have evolved over time and what the remaining shortcomings are. As such, it serves a didactical purpose of introducing apprentices to the field, but it also takes stock of developments so far and reflects on promising new directions. The main focus is on methodological aspects that are particularly relevant for CH4, such as its atmospheric oxidation, the use of methane isotopologues, and specific challenges in atmospheric transport modeling of CH4. The use of satellite retrievals receives special attention as it is an active field of methodological development, with special requirements on the sampling of the model and the treatment of data uncertainty. Regional scale flux estimation and attribution is still a grand challenge, which calls for new methods capable of combining information from multiple data streams of different measured parameters. A process model representation of sources and sinks in atmospheric transport inversion schemes allows the integrated use of such data. These new developments are needed not only to improve our understanding of the main processes driving the observed global trend but also to support international efforts to reduce greenhouse gas emissions.

Challenges and Opportunities: What Can We Learn from Patients Living with Chronic Musculoskeletal Conditions, Health Professionals and Carers about the Concept of Health Literacy Using Qualitative Methods of Inquiry?

PubMed Central

Salter, Charlotte; Brainard, Julii; McDaid, Lisa; Loke, Yoon

2014-01-01

The field of health literacy continues to evolve and concern public health researchers and yet remains a largely overlooked concept elsewhere in the healthcare system. We conducted focus group discussions in England UK, about the concept of health literacy with older patients with chronic musculoskeletal conditions (mean age  = 73.4 years), carers and health professionals. Our research posed methodological, intellectual and practical challenges. Gaps in conceptualisation and expectations were revealed, reiterating deficiencies in predominant models for understanding health literacy and methodological shortcomings of using focus groups in qualitative research for this topic. Building on this unique insight into what the concept of health literacy meant to participants, we present analysis of our findings on factors perceived to foster and inhibit health literacy and on the issue of responsibility in health literacy. Patients saw health literacy as a result of an inconsistent interactive process and the implications as wide ranging; healthcare professionals had more heterogeneous views. All focus group discussants agreed that health literacy most benefited from good inter-personal communication and partnership. By proposing a needs-based approach to health literacy we offer an alternative way of conceptualising health literacy to help improve the health of older people with chronic conditions. PMID:25375767

Implications of the licensure of a partially efficacious malaria vaccine on evaluating second-generation vaccines

PubMed Central

2013-01-01

Background Malaria is a leading cause of morbidity and mortality, with approximately 225 million clinical episodes and >1.2 million deaths annually attributed to malaria. Development of a highly efficacious malaria vaccine will offer unparalleled possibilities for disease prevention and remains a key priority for long-term malaria control and elimination. Discussion The Malaria Vaccine Technology Roadmap’s goal is to 'develop and license a first-generation malaria vaccine that has protective efficacy of more than 50%’. To date, malaria vaccine candidates have only been shown to be partially efficacious (approximately 30% to 60%). However, licensure of a partially effective vaccine will create a number of challenges for the development and progression of new, potentially more efficacious, malaria vaccines in the future. In this opinion piece we discuss the methodological, logistical and ethical issues that may impact on the feasibility and implementation of superiority, non-inferiority and equivalence trials to assess second generation malaria vaccines in the advent of the licensure of a partially efficacious malaria vaccine. Conclusions Selecting which new malaria vaccines go forward, and defining appropriate methodology for assessment in logistically challenging clinical trials, is crucial. It is imperative that the scientific community considers all the issues and starts planning how second-generation malaria vaccines will advance in the advent of licensure of a partially effective vaccine. PMID:24228861

EEG-Informed fMRI: A Review of Data Analysis Methods

PubMed Central

Abreu, Rodolfo; Leal, Alberto; Figueiredo, Patrícia

2018-01-01

The simultaneous acquisition of electroencephalography (EEG) with functional magnetic resonance imaging (fMRI) is a very promising non-invasive technique for the study of human brain function. Despite continuous improvements, it remains a challenging technique, and a standard methodology for data analysis is yet to be established. Here we review the methodologies that are currently available to address the challenges at each step of the data analysis pipeline. We start by surveying methods for pre-processing both EEG and fMRI data. On the EEG side, we focus on the correction for several MR-induced artifacts, particularly the gradient and pulse artifacts, as well as other sources of EEG artifacts. On the fMRI side, we consider image artifacts induced by the presence of EEG hardware inside the MR scanner, and the contamination of the fMRI signal by physiological noise of non-neuronal origin, including a review of several approaches to model and remove it. We then provide an overview of the approaches specifically employed for the integration of EEG and fMRI when using EEG to predict the blood oxygenation level dependent (BOLD) fMRI signal, the so-called EEG-informed fMRI integration strategy, the most commonly used strategy in EEG-fMRI research. Finally, we systematically review methods used for the extraction of EEG features reflecting neuronal phenomena of interest. PMID:29467634

Neural mechanisms of rhythm perception: current findings and future perspectives.

PubMed

Grahn, Jessica A

2012-10-01

Perception of temporal patterns is fundamental to normal hearing, speech, motor control, and music. Certain types of pattern understanding are unique to humans, such as musical rhythm. Although human responses to musical rhythm are universal, there is much we do not understand about how rhythm is processed in the brain. Here, I consider findings from research into basic timing mechanisms and models through to the neuroscience of rhythm and meter. A network of neural areas, including motor regions, is regularly implicated in basic timing as well as processing of musical rhythm. However, fractionating the specific roles of individual areas in this network has remained a challenge. Distinctions in activity patterns appear between "automatic" and "cognitively controlled" timing processes, but the perception of musical rhythm requires features of both automatic and controlled processes. In addition, many experimental manipulations rely on participants directing their attention toward or away from certain stimulus features, and measuring corresponding differences in neural activity. Many temporal features, however, are implicitly processed whether attended to or not, making it difficult to create controlled baseline conditions for experimental comparisons. The variety of stimuli, paradigms, and definitions can further complicate comparisons across domains or methodologies. Despite these challenges, the high level of interest and multitude of methodological approaches from different cognitive domains (including music, language, and motor learning) have yielded new insights and hold promise for future progress. Copyright © 2012 Cognitive Science Society, Inc.

New challenges for Life Sciences flight project management

NASA Technical Reports Server (NTRS)

Huntoon, C. L.

1999-01-01

Scientists have conducted studies involving human spaceflight crews for over three decades. These studies have progressed from simple observations before and after each flight to sophisticated experiments during flights of several weeks up to several months. The findings from these experiments are available in the scientific literature. Management of these flight experiments has grown into a system fashioned from the Apollo Program style, focusing on budgeting, scheduling and allocation of human and material resources. While these areas remain important to the future, the International Space Station (ISS) requires that the Life Sciences spaceflight experiments expand the existing project management methodology. The use of telescience with state-the-art information technology and the multi-national crews and investigators challenges the former management processes. Actually conducting experiments on board the ISS will be an enormous undertaking and International Agreements and Working Groups will be essential in giving guidance to the flight project management Teams forged in this matrix environment must be competent to make decisions and qualified to work with the array of engineers, scientists, and the spaceflight crews. In order to undertake this complex task, data systems not previously used for these purposes must be adapted so that the investigators and the project management personnel can all share in important information as soon as it is available. The utilization of telescience and distributed experiment operations will allow the investigator to remain involved in their experiment as well as to understand the numerous issues faced by other elements of the program The complexity in formation and management of project teams will be a new kind of challenge for international science programs. Meeting that challenge is essential to assure success of the International Space Station as a laboratory in space.

New challenges for Life Sciences flight project management.

PubMed

Huntoon, C L

1999-01-01

Scientists have conducted studies involving human spaceflight crews for over three decades. These studies have progressed from simple observations before and after each flight to sophisticated experiments during flights of several weeks up to several months. The findings from these experiments are available in the scientific literature. Management of these flight experiments has grown into a system fashioned from the Apollo Program style, focusing on budgeting, scheduling and allocation of human and material resources. While these areas remain important to the future, the International Space Station (ISS) requires that the Life Sciences spaceflight experiments expand the existing project management methodology. The use of telescience with state-the-art information technology and the multi-national crews and investigators challenges the former management processes. Actually conducting experiments on board the ISS will be an enormous undertaking and International Agreements and Working Groups will be essential in giving guidance to the flight project management Teams forged in this matrix environment must be competent to make decisions and qualified to work with the array of engineers, scientists, and the spaceflight crews. In order to undertake this complex task, data systems not previously used for these purposes must be adapted so that the investigators and the project management personnel can all share in important information as soon as it is available. The utilization of telescience and distributed experiment operations will allow the investigator to remain involved in their experiment as well as to understand the numerous issues faced by other elements of the program The complexity in formation and management of project teams will be a new kind of challenge for international science programs. Meeting that challenge is essential to assure success of the International Space Station as a laboratory in space.

New challenges for life sciences flight project management

NASA Astrophysics Data System (ADS)

Huntoon, Carolyn L.

1999-09-01

Scientists have conducted studies involving human spaceflight crews for over three decades. These studies have progressed from simple observations before and after each flight to sophisticated experiments during flights of several weeks up to several months. The findings from these experiments are available in the scientific literature. Management of these flight experiments has grown into a system fashioned from the Apollo Program style, focusing on budgeting, scheduling and allocation of human and material resources. While these areas remain important to the future, the International Space Station (ISS) requires that the Life Sciences spaceflight experiments expand the existing project management methodology. The use of telescience with state-of-the-art information technology and the multi-national crews and investigators challenges the former management processes. Actually conducting experiments on board the ISS will be an enormous undertaking and International Agreements and Working Groups will be essential in giving guidance to the flight project management Teams forged in this matrix environment must be competent to make decisions and qualified to work with the array of engineers, scientists, and the spaceflight crews. In order to undertake this complex task, data systems not previously used for these purposes must be adapted so that the investigators and the project management personnel can all share in important information as soon as it is available. The utilization of telescience and distributed experiment operations will allow the investigator to remain involved in their experiment as well as to understand the numerous issues faced by other elements of the program. The complexity in formation and management of project teams will be a new kind of challenge for international science programs. Meeting that challenge is essential to assure success of the International Space Station as a laboratory in space.

Methodological and ethical challenges in studying patients’ perceptions of coercion: a systematic mixed studies review

PubMed Central

2014-01-01

Background Despite improvements in psychiatric inpatient care, patient restrictions in psychiatric hospitals are still in use. Studying perceptions among patients who have been secluded or physically restrained during their hospital stay is challenging. We sought to review the methodological and ethical challenges in qualitative and quantitative studies aiming to describe patients’ perceptions of coercive measures, especially seclusion and physical restraints during their hospital stay. Methods Systematic mixed studies review was the study method. Studies reporting patients’ perceptions of coercive measures, especially seclusion and physical restraints during hospital stay were included. Methodological issues such as study design, data collection and recruitment process, participants, sampling, patient refusal or non-participation, and ethical issues such as informed consent process, and approval were synthesized systematically. Electronic searches of CINALH, MEDLINE, PsychINFO and The Cochrane Library (1976-2012) were carried out. Results Out of 846 initial citations, 32 studies were included, 14 qualitative and 18 quantitative studies. A variety of methodological approaches were used, although descriptive and explorative designs were used in most cases. Data were mainly collected in qualitative studies by interviews (n = 13) or in quantitative studies by self-report questionnaires (n = 12). The recruitment process was explained in 59% (n = 19) of the studies. In most cases convenience sampling was used, yet five studies used randomization. Patient’s refusal or non-participation was reported in 37% (n = 11) of studies. Of all studies, 56% (n = 18) had reported undergone an ethical review process in an official board or committee. Respondents were informed and consent was requested in 69% studies (n = 22). Conclusions The use of different study designs made comparison methodologically challenging. The timing of data collection (considering bias and confounding factors) and the reasons for non-participation of eligible participants are likewise methodological challenges, e.g. recommended flow charts could aid the information. Other challenges identified were the recruitment of large and representative samples. Ethical challenges included requesting participants’ informed consent and respecting ethical procedures. PMID:24894162

The Evolution of an Interprofessional Shared Decision-Making Research Program: Reflective Case Study of an Emerging Paradigm

PubMed Central

Menear, Matthew; Stacey, Dawn; Brière, Nathalie; Légaré, France

2016-01-01

Introduction: Healthcare research increasingly focuses on interprofessional collaboration and on shared decision making, but knowledge gaps remain about effective strategies for implementing interprofessional collaboration and shared decision-making together in clinical practice. We used Kuhn’s theory of scientific revolutions to reflect on how an integrated interprofessional shared decision-making approach was developed and implemented over time. Methods: In 2007, an interdisciplinary team initiated a new research program to promote the implementation of an interprofessional shared decision-making approach in clinical settings. For this reflective case study, two new team members analyzed the team’s four projects, six research publications, one unpublished and two published protocols and organized them into recognizable phases according to Kuhn’s theory. Results: The merging of two young disciplines led to challenges characteristic of emerging paradigms. Implementation of interprofessional shared-decision making was hindered by a lack of conceptual clarity, a dearth of theories and models, little methodological guidance, and insufficient evaluation instruments. The team developed a new model, identified new tools, and engaged knowledge users in a theory-based approach to implementation. However, several unresolved challenges remain. Discussion: This reflective case study sheds light on the evolution of interdisciplinary team science. It offers new approaches to implementing emerging knowledge in the clinical context. PMID:28435417

The Evolution of an Interprofessional Shared Decision-Making Research Program: Reflective Case Study of an Emerging Paradigm.

PubMed

Dogba, Maman Joyce; Menear, Matthew; Stacey, Dawn; Brière, Nathalie; Légaré, France

2016-07-19

Healthcare research increasingly focuses on interprofessional collaboration and on shared decision making, but knowledge gaps remain about effective strategies for implementing interprofessional collaboration and shared decision-making together in clinical practice. We used Kuhn's theory of scientific revolutions to reflect on how an integrated interprofessional shared decision-making approach was developed and implemented over time. In 2007, an interdisciplinary team initiated a new research program to promote the implementation of an interprofessional shared decision-making approach in clinical settings. For this reflective case study, two new team members analyzed the team's four projects, six research publications, one unpublished and two published protocols and organized them into recognizable phases according to Kuhn's theory. The merging of two young disciplines led to challenges characteristic of emerging paradigms. Implementation of interprofessional shared-decision making was hindered by a lack of conceptual clarity, a dearth of theories and models, little methodological guidance, and insufficient evaluation instruments. The team developed a new model, identified new tools, and engaged knowledge users in a theory-based approach to implementation. However, several unresolved challenges remain. This reflective case study sheds light on the evolution of interdisciplinary team science. It offers new approaches to implementing emerging knowledge in the clinical context.

Research Methodology in Second Language Studies: Trends, Concerns, and New Directions

ERIC Educational Resources Information Center

King, Kendall A.; Mackey, Alison

2016-01-01

The field of second language studies is using increasingly sophisticated methodological approaches to address a growing number of urgent, real-world problems. These methodological developments bring both new challenges and opportunities. This article briefly reviews recent ontological and methodological debates in the field, then builds on these…

A Comparison of Randomised Controlled Trials in Health and Education

ERIC Educational Resources Information Center

Torgerson, Carole J.; Torgerson, David J.; Birks, Yvonne F.; Porthouse, Jill

2005-01-01

Health care and educational trials face similar methodological challenges. Methodological reviews of health care trials have shown that a significant proportion have methodological flaws. Whether or not educational trials have a similar proportion of poor-quality trials is unknown. The authors undertook a methodological comparison between health…

The Challenges of Managing Transnational Education Partnerships: The Views of "Home-Based" Managers vs "In-Country" Managers

ERIC Educational Resources Information Center

Healey, Nigel Martin

2018-01-01

Purpose: The purpose of this paper is to investigate the challenges of managing transnational education (TNE) partnerships from the perspective of the home university managers. Design/methodology/approach: The study adopts a qualitative, "insider researcher" methodology. It uses a sample set of eight mangers who operate from the home…

Psychology and Aging: The First 20 Years

PubMed Central

Zacks, Rose T.; Blanchard-Fields, Fredda; Haley, William E.

2006-01-01

This article provides a review of the first 20 years of Psychology and Aging, the American Psychological Association’s first and only scholarly journal devoted to the topic of aging. The authors briefly summarize its history, its contributions to the study of aging, and its broader status as a scholarly publication. One theme highlighted in our review is the diversity of content in the journal throughout its history. Another is the strong impact that articles published in the journal have had on both basic and applied topics in aging. Efforts to encompass the breadth of topics and methodologies in aging research while retaining excellent quality remain the exciting but essential challenge for Psychology and Aging. PMID:16594786

Radiation Testing Electronics with Heavy Ions-The Best Way to Hit a Target Moving Ever Exponentially Faster

NASA Technical Reports Server (NTRS)

Ladbury, Ray

2018-01-01

In 1972, when engineers at Hughes Aircraft Corporation discovered that errors in their satellite avionics were being caused by cosmic rays (so-called single-event effects, or SEE), Moore's Law was only 7 years old. Now, more than 45 years on, the scaling that drove Moore's Law for its first 35 years has reached its limits. However, electronics technology continues to evolve exponentially and SEE remain a formidable issue for use of electronics in space. SEE occur when a single ionizing particle passes through a sensitive volume in an active semiconductor device and generates sufficient charge to cause anomalous behavior or failure in the device. Because SEE can occur at any time during the mission, the emphasis of SEE risk management methodologies is ensuring that all SEE modes in a device under test are detected by the test. Because a particle's probability of causing an SEE generally increases as the particle becomes more ionizing, heavy-ion beams have been and remain the preferred tools for elucidating SEE vulnerabilities. In this talk we briefly discuss space radiation environments and SEE mechanisms, describe SEE test methodologies and discuss current and future challenges for use of heavy-ion beams for SEE testing in an era when the continued validity of Moore's law depends on innovation rather than CMOS scaling.

76 FR 9544 - Antidumping Methodologies in Proceedings Involving Non-Market Economies: Valuing the Factor of...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-18

... parties to comment on these methodological issues described above. Request for Comment on Interim Industry... comments. \\15\\ Indicator: GNI per capita, Atlas Method (current US$) is obtained from http://data.worldbank... methodology, the Department has encountered a number of methodological and practical challenges that must be...

Second Language Listening Strategy Research: Methodological Challenges and Perspectives

ERIC Educational Resources Information Center

Santos, Denise; Graham, Suzanne; Vanderplank, Robert

2008-01-01

This paper explores methodological issues related to research into second language listening strategies. We argue that a number of central questions regarding research methodology in this line of enquiry are underexamined, and we engage in the discussion of three key methodological questions: (1) To what extent is a verbal report a valid and…

A Model-based Prognostics Methodology for Electrolytic Capacitors Based on Electrical Overstress Accelerated Aging

NASA Technical Reports Server (NTRS)

Celaya, Jose; Kulkarni, Chetan; Biswas, Gautam; Saha, Sankalita; Goebel, Kai

2011-01-01

A remaining useful life prediction methodology for electrolytic capacitors is presented. This methodology is based on the Kalman filter framework and an empirical degradation model. Electrolytic capacitors are used in several applications ranging from power supplies on critical avionics equipment to power drivers for electro-mechanical actuators. These devices are known for their comparatively low reliability and given their criticality in electronics subsystems they are a good candidate for component level prognostics and health management. Prognostics provides a way to assess remaining useful life of a capacitor based on its current state of health and its anticipated future usage and operational conditions. We present here also, experimental results of an accelerated aging test under electrical stresses. The data obtained in this test form the basis for a remaining life prediction algorithm where a model of the degradation process is suggested. This preliminary remaining life prediction algorithm serves as a demonstration of how prognostics methodologies could be used for electrolytic capacitors. In addition, the use degradation progression data from accelerated aging, provides an avenue for validation of applications of the Kalman filter based prognostics methods typically used for remaining useful life predictions in other applications.

Towards A Model-Based Prognostics Methodology for Electrolytic Capacitors: A Case Study Based on Electrical Overstress Accelerated Aging

NASA Technical Reports Server (NTRS)

Celaya, Jose R.; Kulkarni, Chetan S.; Biswas, Gautam; Goebel, Kai

2012-01-01

A remaining useful life prediction methodology for electrolytic capacitors is presented. This methodology is based on the Kalman filter framework and an empirical degradation model. Electrolytic capacitors are used in several applications ranging from power supplies on critical avionics equipment to power drivers for electro-mechanical actuators. These devices are known for their comparatively low reliability and given their criticality in electronics subsystems they are a good candidate for component level prognostics and health management. Prognostics provides a way to assess remaining useful life of a capacitor based on its current state of health and its anticipated future usage and operational conditions. We present here also, experimental results of an accelerated aging test under electrical stresses. The data obtained in this test form the basis for a remaining life prediction algorithm where a model of the degradation process is suggested. This preliminary remaining life prediction algorithm serves as a demonstration of how prognostics methodologies could be used for electrolytic capacitors. In addition, the use degradation progression data from accelerated aging, provides an avenue for validation of applications of the Kalman filter based prognostics methods typically used for remaining useful life predictions in other applications.

Challenges to the Learning Organization in the Context of Generational Diversity and Social Networks

ERIC Educational Resources Information Center

Kaminska, Renata; Borzillo, Stefano

2018-01-01

Purpose: The purpose of this paper is to gain a better understanding of the challenges to the emergence of a learning organization (LO) posed by a context of generational diversity and an enterprise social networking system (ESNS). Design/methodology/approach: This study uses a qualitative methodology based on an analysis of 20 semi-structured…

Sexuality Research in Iran: A Focus on Methodological and Ethical Considerations.

PubMed

Rahmani, Azam; Merghati-Khoei, Effat; Moghaddam-Banaem, Lida; Zarei, Fatemeh; Montazeri, Ali; Hajizadeh, Ebrahim

2015-07-01

Research on sensitive topics, such as sexuality, could raise technical, methodological, ethical, political, and legal challenges. The aim of this paper was to draw the methodological challenges which the authors confronted during sexuality research with young population in the Iranian culture. This study was an exploratory mixed method one conducted in 2013-14. We interviewed 63 young women aged 18-34 yr in qualitative phase and 265 young women in quantitative phase in (university and non-university) dormitories and in an Adolescent Friendly Center. Data were collected using focus group discussions and individual interviews in the qualitative phase. We employed conventional content analysis to analyze the data. To enhance the rigor of the data, multiple data collection methods, maximum variation sampling, and peer checks were applied. Five main themes emerged from the data: interaction with opposite sex, sexual risk, sexual protective, sex education, and sexual vulnerability. Challenges while conducting sex research have been discussed. These challenges included assumption of promiscuity, language of silence and privacy concerns, and sex segregation policy. We described the strategies applied in our study and the rationales for each strategy. Strategies applied in the present study can be employed in contexts with the similar methodological and moral concerns.

Perspectives for elucidating the ethylenediurea (EDU) mode of action for protection against O3 phytotoxicity.

PubMed

Agathokleous, Evgenios

2017-08-01

Ethylenediurea (EDU) has been widely studied for its effectiveness to protect plants against injuries caused by surface ozone (O 3 ), however its mode of action remains unclear. So far, there is not a unified methodological approach and thus the methodology is quite arbitrary, thereby making it more difficult to generalize findings and understand the EDU mode of action. This review examines the question of whether potential N addition to plants by EDU is a fundamental underlying mechanism in protecting against O 3 phytotoxicity. Yet, this review proposes an evidence-based hypothesis that EDU may protect plants against O 3 deleterious effects upon generation of EDU-induced hormesis, i.e. by activating plant defense at low doses. This hypothesis challenges the future research directions. Revealing a hormesis-based EDU mode of action in protecting plants against O 3 toxicity would have further implications to ecotoxicology and environmental safety. Furthermore, this review discusses the need for further studies on plant metabolism under EDU treatment through relevant experimental approach, and attempts to set the bases for approaching a unified methodology that will contribute in revealing the EDU mode of action. In this framework, focus is given to the main EDU application methods. Copyright © 2017 Elsevier Inc. All rights reserved.

Building a genome analysis pipeline to predict disease risk and prevent disease.

PubMed

Bromberg, Y

2013-11-01

Reduced costs and increased speed and accuracy of sequencing can bring the genome-based evaluation of individual disease risk to the bedside. While past efforts have identified a number of actionable mutations, the bulk of genetic risk remains hidden in sequence data. The biggest challenge facing genomic medicine today is the development of new techniques to predict the specifics of a given human phenome (set of all expressed phenotypes) encoded by each individual variome (full set of genome variants) in the context of the given environment. Numerous tools exist for the computational identification of the functional effects of a single variant. However, the pipelines taking advantage of full genomic, exomic, transcriptomic (and other) sequences have only recently become a reality. This review looks at the building of methodologies for predicting "variome"-defined disease risk. It also discusses some of the challenges for incorporating such a pipeline into everyday medical practice. © 2013. Published by Elsevier Ltd. All rights reserved.

Diagnosing Breast Cancer with Microwave Technology: remaining challenges and potential solutions with machine learning.

PubMed

Oliveira, Bárbara L; Godinho, Daniela; O'Halloran, Martin; Glavin, Martin; Jones, Edward; Conceição, Raquel C

2018-05-19

Currently, breast cancer often requires invasive biopsies for diagnosis, motivating researchers to design and develop non-invasive and automated diagnosis systems. Recent microwave breast imaging studies have shown how backscattered signals carry relevant information about the shape of a tumour, and tumour shape is often used with current imaging modalities to assess malignancy. This paper presents a comprehensive analysis of microwave breast diagnosis systems which use machine learning to learn characteristics of benign and malignant tumours. The state-of-the-art, the main challenges still to overcome and potential solutions are outlined. Specifically, this work investigates the benefit of signal pre-processing on diagnostic performance, and proposes a new set of extracted features that capture the tumour shape information embedded in a signal. This work also investigates if a relationship exists between the antenna topology in a microwave system and diagnostic performance. Finally, a careful machine learning validation methodology is implemented to guarantee the robustness of the results and the accuracy of performance evaluation.

Expanding multi-disciplinary approaches to healthcare information technologies: what does information systems offer medical informatics?

PubMed

Chiasson, Mike; Reddy, Madhu; Kaplan, Bonnie; Davidson, Elizabeth

2007-06-01

The effective use of information technology (IT) is a crucial component for the delivery of effective services in health care. Current approaches to medical informatics (MI) research have significantly contributed to the success of IT use in health care but important challenges remain to be addressed. We believe that expanding the multi-disciplinary basis for MI research is important to meeting these research challenges. In this paper, we outline theories and methods used in information systems (IS) research that we believe can inform our understanding of health care IT applications and outcomes. To do so, we discuss some general differences in the focus and methods of MI and IS research to identify broad opportunities. We then review conceptual and methodological approaches in IS that have been applied in health care IT research. These include: technology-use mediation, collaborative work, genre theory, interpretive research, action research, and modeling. Examples of these theories and methods in healthcare IS research are illustrated.

Decontaminate feature for tracking: adaptive tracking via evolutionary feature subset

NASA Astrophysics Data System (ADS)

Liu, Qiaoyuan; Wang, Yuru; Yin, Minghao; Ren, Jinchang; Li, Ruizhi

2017-11-01

Although various visual tracking algorithms have been proposed in the last 2-3 decades, it remains a challenging problem for effective tracking with fast motion, deformation, occlusion, etc. Under complex tracking conditions, most tracking models are not discriminative and adaptive enough. When the combined feature vectors are inputted to the visual models, this may lead to redundancy causing low efficiency and ambiguity causing poor performance. An effective tracking algorithm is proposed to decontaminate features for each video sequence adaptively, where the visual modeling is treated as an optimization problem from the perspective of evolution. Every feature vector is compared to a biological individual and then decontaminated via classical evolutionary algorithms. With the optimized subsets of features, the "curse of dimensionality" has been avoided while the accuracy of the visual model has been improved. The proposed algorithm has been tested on several publicly available datasets with various tracking challenges and benchmarked with a number of state-of-the-art approaches. The comprehensive experiments have demonstrated the efficacy of the proposed methodology.

Skeletal Muscle Tissue Engineering: Methods to Form Skeletal Myotubes and Their Applications

PubMed Central

Ostrovidov, Serge; Hosseini, Vahid; Ahadian, Samad; Fujie, Toshinori; Parthiban, Selvakumar Prakash; Ramalingam, Murugan; Bae, Hojae; Kaji, Hirokazu

2014-01-01

Skeletal muscle tissue engineering (SMTE) aims to repair or regenerate defective skeletal muscle tissue lost by traumatic injury, tumor ablation, or muscular disease. However, two decades after the introduction of SMTE, the engineering of functional skeletal muscle in the laboratory still remains a great challenge, and numerous techniques for growing functional muscle tissues are constantly being developed. This article reviews the recent findings regarding the methodology and various technical aspects of SMTE, including cell alignment and differentiation. We describe the structure and organization of muscle and discuss the methods for myoblast alignment cultured in vitro. To better understand muscle formation and to enhance the engineering of skeletal muscle, we also address the molecular basics of myogenesis and discuss different methods to induce myoblast differentiation into myotubes. We then provide an overview of different coculture systems involving skeletal muscle cells, and highlight major applications of engineered skeletal muscle tissues. Finally, potential challenges and future research directions for SMTE are outlined. PMID:24320971

Cleaning and Disinfection of Bacillus cereus Biofilm.

PubMed

Deal, Amanda; Klein, Dan; Lopolito, Paul; Schwarz, John Spencer

2016-01-01

Methodology has been evolving for the testing of disinfectants against bacterial single-species biofilms, as the difficulty of biofilm remediation continues to gain much-needed attention. Bacterial single-species biofilm contamination presents a real risk to good manufacturing practice-regulated industries. However, mixed-species biofilms and biofilms containing bacterial spores remain an even greater challenge for cleaning and disinfection. Among spore-forming microorganisms frequently encountered in pharmaceutical manufacturing areas, the spores of Bacillus cereus are often determined to be the hardest to disinfect and eradicate. One of the reasons for the low degree of susceptibility to disinfection is the ability of these spores to be encapsulated within an exopolysachharide biofilm matrix. In this series of experiments, we evaluated the disinfectant susceptibility of B. cereus biofilms relative to disassociated B. cereus spores and biofilm from a non-spore-forming species. Further, we assessed the impact that pre-cleaning has on increasing that susceptibility. Methodology has been evolving for the testing of disinfectants against bacterial single-species biofilms, as the difficulty of biofilm remediation continues to gain much-needed attention. Bacterial single-species biofilm contamination presents a real risk to good manufacturing practice-regulated industries. However, mixed-species biofilms and biofilms containing bacterial spores remain an even greater challenge for cleaning and disinfection. Among spore-forming microorganisms frequently encountered in pharmaceutical manufacturing areas, the spores of Bacillus cereus are often determined to be the hardest to disinfect and eradicate. One of the reasons for the low degree of susceptibility to disinfection is the ability of these spores to be encapsulated within an exopolysachharide biofilm matrix. In this series of experiments, we evaluated the disinfectant susceptibility of B. cereus biofilms relative to disassociated B. cereus spores and biofilm from a non-spore-forming species. Further, we assessed the impact that pre-cleaning has on increasing that susceptibility. © PDA, Inc. 2016.

Integrated teaching program using case-based learning

PubMed Central

Bhardwaj, Pankaj; Bhardwaj, Nikha; Mahdi, Farzana; Srivastava, J P; Gupta, Uma

2015-01-01

Background: At present, in a medical school, students are taught in different departments, subject-wise, without integration to interrelate or unify subjects and these results in compartmentalization of medical education, with no stress on case-based learning. Therefore, an effort was made to develop and adopt integrated teaching in order to have a better contextual knowledge among students. Methodology and Implementation: After the faculty orientation training, four “topic committees” with faculty members from different departments were constituted which decided and agreed on the content material to be taught, different methodologies to be used, along with the logical sequencing of the same for the purpose of implementation. Different teaching methodologies used, during the program, were didactic lectures, case stimulated sessions, clinical visits, laboratory work, and small group student's seminar. Results: After the implementation of program, the comparison between two batches as well as between topics taught with integrated learning program versus traditional method showed that students performed better in the topics, taught with integrated approach. Students rated “clinical visits” as very good methodology, followed by “case stimulated interactive sessions.” Students believed that they felt more actively involved, and their queries are better addressed with such interactive sessions. Conclusion: There is a very good perception of students toward integrated teaching. Students performed better if they are taught using this technique. Although majority of faculty found integrated teaching, as useful method of teaching, nevertheless extra work burden and interdepartmental coordination remained a challenging task. PMID:26380204

Feminist-informed participatory action research: a methodology of choice for examining critical nursing issues.

PubMed

Corbett, Andrea M; Francis, Karen; Chapman, Ysanne

2007-04-01

Identifying a methodology to guide a study that aims to enhance service delivery can be challenging. Participatory action research offers a solution to this challenge as it both informs and is informed by critical social theory. In addition, using a feminist lens helps acquiesce this approach as a suitable methodology for changing practice. This methodology embraces empowerment self-determination and the facilitation of agreed change as central tenets that guide the research process. Encouraged by the work of Foucault, Friere, Habermas, and Maguire, this paper explicates the philosophical assumptions underpinning critical social theory and outlines how feminist influences are complimentary in exploring the processes and applications of nursing research that seeks to embrace change.

Applying species-tree analyses to deep phylogenetic histories: challenges and potential suggested from a survey of empirical phylogenetic studies.

PubMed

Lanier, Hayley C; Knowles, L Lacey

2015-02-01

Coalescent-based methods for species-tree estimation are becoming a dominant approach for reconstructing species histories from multi-locus data, with most of the studies examining these methodologies focused on recently diverged species. However, deeper phylogenies, such as the datasets that comprise many Tree of Life (ToL) studies, also exhibit gene-tree discordance. This discord may also arise from the stochastic sorting of gene lineages during the speciation process (i.e., reflecting the random coalescence of gene lineages in ancestral populations). It remains unknown whether guidelines regarding methodologies and numbers of loci established by simulation studies at shallow tree depths translate into accurate species relationships for deeper phylogenetic histories. We address this knowledge gap and specifically identify the challenges and limitations of species-tree methods that account for coalescent variance for deeper phylogenies. Using simulated data with characteristics informed by empirical studies, we evaluate both the accuracy of estimated species trees and the characteristics associated with recalcitrant nodes, with a specific focus on whether coalescent variance is generally responsible for the lack of resolution. By determining the proportion of coalescent genealogies that support a particular node, we demonstrate that (1) species-tree methods account for coalescent variance at deep nodes and (2) mutational variance - not gene-tree discord arising from the coalescent - posed the primary challenge for accurate reconstruction across the tree. For example, many nodes were accurately resolved despite predicted discord from the random coalescence of gene lineages and nodes with poor support were distributed across a range of depths (i.e., they were not restricted to a particular recent divergences). Given their broad taxonomic scope and large sampling of taxa, deep level phylogenies pose several potential methodological complications including difficulties with MCMC convergence and estimation of requisite population genetic parameters for coalescent-based approaches. Despite these difficulties, the findings generally support the utility of species-tree analyses for the estimation of species relationships throughout the ToL. We discuss strategies for successful application of species-tree approaches to deep phylogenies. Copyright © 2014 Elsevier Inc. All rights reserved.

Economic evaluation of health promotion interventions for older people: do applied economic studies meet the methodological challenges?

PubMed

Huter, Kai; Dubas-Jakóbczyk, Katarzyna; Kocot, Ewa; Kissimova-Skarbek, Katarzyna; Rothgang, Heinz

2018-01-01

In the light of demographic developments health promotion interventions for older people are gaining importance. In addition to methodological challenges arising from the economic evaluation of health promotion interventions in general, there are specific methodological problems for the particular target group of older people. There are especially four main methodological challenges that are discussed in the literature. They concern measurement and valuation of informal caregiving, accounting for productivity costs, effects of unrelated cost in added life years and the inclusion of 'beyond-health' benefits. This paper focuses on the question whether and to what extent specific methodological requirements are actually met in applied health economic evaluations. Following a systematic review of pertinent health economic evaluations, the included studies are analysed on the basis of four assessment criteria that are derived from methodological debates on the economic evaluation of health promotion interventions in general and economic evaluations targeting older people in particular. Of the 37 studies included in the systematic review, only very few include cost and outcome categories discussed as being of specific relevance to the assessment of health promotion interventions for older people. The few studies that consider these aspects use very heterogeneous methods, thus there is no common methodological standard. There is a strong need for the development of guidelines to achieve better comparability and to include cost categories and outcomes that are relevant for older people. Disregarding these methodological obstacles could implicitly lead to discrimination against the elderly in terms of health promotion and disease prevention and, hence, an age-based rationing of public health care.

Interviewing with or without the partner present?--an underexposed dilemma between ethics and methodology in nursing research.

PubMed

Norlyk, Annelise; Haahr, Anita; Hall, Elisabeth

2016-04-01

To discuss ethical and methodological challenges related to in-depth interviews with patients and partners when interviewed together or separately. Increased interest in exploring illness phenomena from both patients' and partners' perspectives has emerged. The decision about how to collect data is challenging. Patients and partners can be interviewed separately or together; in both scenarios researchers face complex questions of methodology and ethics. This paper contributes to the ongoing debate on individual or joint interviewing and the effect of absence/presence of the partner on data collection. Discussion paper that draws on data from three phenomenological studies. Referring to three cases from our phenomenological studies, we discuss the different types of ethical and methodological dilemmas faced when undertaking joint and separate interviews with couples. Furthermore, we discuss how the unexpected presence of the partner potentially influences the data gathered from the patient. The cases demonstrate the interrelatedness of ethics and methodology in studies based on in-depth interviews with couples. Nurse researchers may be caught up in a dilemma between ethical concerns and methodological considerations. We argue that the presence of the partner during an interview session might influence the data and favour expressions of shared rather than individual experiences of the phenomenon studied. Furthermore, we argue that ethical concerns must be given higher priority than methodology when interviewing couples. An increased awareness of the tension between ethical and methodological challenges in joint or individual interviewing with patients and partners is necessary, as this issue is underexposed. © 2015 John Wiley & Sons Ltd.

Product environmental footprint in policy and market decisions: Applicability and impact assessment.

PubMed

Lehmann, Annekatrin; Bach, Vanessa; Finkbeiner, Matthias

2015-07-01

In April 2013, the European Commission published the Product and Organisation Environmental Footprint (PEF/OEF) methodology--a life cycle-based multicriteria measure of the environmental performance of products, services, and organizations. With its approach of "comparability over flexibility," the PEF/OEF methodology aims at harmonizing existing methods, while decreasing the flexibility provided by the International Organization for Standardization (ISO) standards regarding methodological choices. Currently, a 3-y pilot phase is running, aiming at testing the methodology and developing product category and organization sector rules (PEFCR/OEFSR). Although a harmonized method is in theory a good idea, the PEF/OEF methodology presents challenges, including a risk of confusion and limitations in applicability to practice. The paper discusses the main differences between the PEF and ISO methodologies and highlights challenges regarding PEF applicability, with a focus on impact assessment. Some methodological aspects of the PEF and PEFCR Guides are found to contradict the ISO 14044 (2006) and ISO 14025 (2006). Others, such as prohibition of inventory cutoffs, are impractical. The evaluation of the impact assessment methods proposed in the PEF/OEF Guide showed that the predefined methods for water consumption, land use, and abiotic resources are not adequate because of modeling artefacts, missing inventory data, or incomplete characterization factors. However, the methods for global warming and ozone depletion perform very well. The results of this study are relevant for the PEF (and OEF) pilot phase, which aims at testing the PEF (OEF) methodology (and potentially adapting it) as well as addressing challenges and coping with them. © 2015 SETAC.

Clinical diabetes research using data mining: a Canadian perspective.

PubMed

Shah, Baiju R; Lipscombe, Lorraine L

2015-06-01

With the advent of the digitization of large amounts of information and the computer power capable of analyzing this volume of information, data mining is increasingly being applied to medical research. Datasets created for administration of the healthcare system provide a wealth of information from different healthcare sectors, and Canadian provinces' single-payer universal healthcare systems mean that data are more comprehensive and complete in this country than in many other jurisdictions. The increasing ability to also link clinical information, such as electronic medical records, laboratory test results and disease registries, has broadened the types of data available for analysis. Data-mining methods have been used in many different areas of diabetes clinical research, including classic epidemiology, effectiveness research, population health and health services research. Although methodologic challenges and privacy concerns remain important barriers to using these techniques, data mining remains a powerful tool for clinical research. Copyright © 2015 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.

Methodological considerations for research on ethnopolitical violence.

PubMed

Little, Todd D

2017-02-01

The methodological and epistemological challenges that research on ethnopolitical violence faces are examined. This research area is fundamentally important for political reasons and for understanding, as well as subsequent interventions to ameliorate, youths' responses to ethnopolitical violence. Advances in methods are reviewed that can overcome the obstacles placed by the various challenges. These issues are discussed in the context of the articles that comprise this Special Section.

Diagnosis of Ebola Virus Disease: Past, Present, and Future

PubMed Central

Brooks, Tim J. G.

2016-01-01

SUMMARY Laboratory diagnosis of Ebola virus disease plays a critical role in outbreak response efforts; however, establishing safe and expeditious testing strategies for this high-biosafety-level pathogen in resource-poor environments remains extremely challenging. Since the discovery of Ebola virus in 1976 via traditional viral culture techniques and electron microscopy, diagnostic methodologies have trended toward faster, more accurate molecular assays. Importantly, technological advances have been paired with increasing efforts to support decentralized diagnostic testing capacity that can be deployed at or near the point of patient care. The unprecedented scope of the 2014-2015 West Africa Ebola epidemic spurred tremendous innovation in this arena, and a variety of new diagnostic platforms that have the potential both to immediately improve ongoing surveillance efforts in West Africa and to transform future outbreak responses have reached the field. In this review, we describe the evolution of Ebola virus disease diagnostic testing and efforts to deploy field diagnostic laboratories in prior outbreaks. We then explore the diagnostic challenges pervading the 2014-2015 epidemic and provide a comprehensive examination of novel diagnostic tests that are likely to address some of these challenges moving forward. PMID:27413095

Methodological challenges and analytic opportunities for modeling and interpreting Big Healthcare Data.

PubMed

Dinov, Ivo D

2016-01-01

Managing, processing and understanding big healthcare data is challenging, costly and demanding. Without a robust fundamental theory for representation, analysis and inference, a roadmap for uniform handling and analyzing of such complex data remains elusive. In this article, we outline various big data challenges, opportunities, modeling methods and software techniques for blending complex healthcare data, advanced analytic tools, and distributed scientific computing. Using imaging, genetic and healthcare data we provide examples of processing heterogeneous datasets using distributed cloud services, automated and semi-automated classification techniques, and open-science protocols. Despite substantial advances, new innovative technologies need to be developed that enhance, scale and optimize the management and processing of large, complex and heterogeneous data. Stakeholder investments in data acquisition, research and development, computational infrastructure and education will be critical to realize the huge potential of big data, to reap the expected information benefits and to build lasting knowledge assets. Multi-faceted proprietary, open-source, and community developments will be essential to enable broad, reliable, sustainable and efficient data-driven discovery and analytics. Big data will affect every sector of the economy and their hallmark will be 'team science'.

Untargeted Metabolomics Strategies—Challenges and Emerging Directions

NASA Astrophysics Data System (ADS)

Schrimpe-Rutledge, Alexandra C.; Codreanu, Simona G.; Sherrod, Stacy D.; McLean, John A.

2016-12-01

Metabolites are building blocks of cellular function. These species are involved in enzyme-catalyzed chemical reactions and are essential for cellular function. Upstream biological disruptions result in a series of metabolomic changes and, as such, the metabolome holds a wealth of information that is thought to be most predictive of phenotype. Uncovering this knowledge is a work in progress. The field of metabolomics is still maturing; the community has leveraged proteomics experience when applicable and developed a range of sample preparation and instrument methodology along with myriad data processing and analysis approaches. Research focuses have now shifted toward a fundamental understanding of the biology responsible for metabolomic changes. There are several types of metabolomics experiments including both targeted and untargeted analyses. While untargeted, hypothesis generating workflows exhibit many valuable attributes, challenges inherent to the approach remain. This Critical Insight comments on these challenges, focusing on the identification process of LC-MS-based untargeted metabolomics studies—specifically in mammalian systems. Biological interpretation of metabolomics data hinges on the ability to accurately identify metabolites. The range of confidence associated with identifications that is often overlooked is reviewed, and opportunities for advancing the metabolomics field are described.

The Promise of Systems Biology Approaches for Revealing Host Pathogen Interactions in Malaria

PubMed Central

Zuck, Meghan; Austin, Laura S.; Danziger, Samuel A.; Aitchison, John D.; Kaushansky, Alexis

2017-01-01

Despite global eradication efforts over the past century, malaria remains a devastating public health burden, causing almost half a million deaths annually (WHO, 2016). A detailed understanding of the mechanisms that control malaria infection has been hindered by technical challenges of studying a complex parasite life cycle in multiple hosts. While many interventions targeting the parasite have been implemented, the complex biology of Plasmodium poses a major challenge, and must be addressed to enable eradication. New approaches for elucidating key host-parasite interactions, and predicting how the parasite will respond in a variety of biological settings, could dramatically enhance the efficacy and longevity of intervention strategies. The field of systems biology has developed methodologies and principles that are well poised to meet these challenges. In this review, we focus our attention on the Liver Stage of the Plasmodium lifecycle and issue a “call to arms” for using systems biology approaches to forge a new era in malaria research. These approaches will reveal insights into the complex interplay between host and pathogen, and could ultimately lead to novel intervention strategies that contribute to malaria eradication. PMID:29201016

The public health impact of food-related illness.

PubMed

O'Brien, Sarah J

2012-10-01

The purpose of this review is to provide an update on the public health impact of food-related illness in light of recent high-profile outbreaks and advances in the methodology to estimate illness burden. It includes mainly literature from high-income countries, as burden of illness estimations have been focussed in these countries. The public health burden of food-related illness is very high, no matter what method is used to measure it. Outbreaks provide only a partial insight because they represent a small proportion of all cases of food-related illness. Recent outbreaks have demonstrated a very wide variety of contaminated food vehicles and illustrated the challenges in investigations when the contaminated foodstuff is an ingredient of many other food items. Outbreaks will continue to challenge public health responses so that maintaining capacity to respond rapidly is crucial. Technological advances, such as whole genome sequencing, pave the way for identifying food-related illness much more rapidly than at present. There is a need to improve diagnostic yield in clinical laboratories and culturing organisms will remain important. Perhaps one of the greatest challenges, though, is to maintain the interest and support of the public when investigating food-related illness.

Guidelines for reporting methodological challenges and evaluating potential bias in dementia research

PubMed Central

Weuve, Jennifer; Proust-Lima, Cécile; Power, Melinda C.; Gross, Alden L.; Hofer, Scott M.; Thiébaut, Rodolphe; Chêne, Geneviève; Glymour, M. Maria; Dufouil, Carole

2015-01-01

Clinical and population research on dementia and related neurologic conditions, including Alzheimer’s disease, faces several unique methodological challenges. Progress to identify preventive and therapeutic strategies rests on valid and rigorous analytic approaches, but the research literature reflects little consensus on “best practices.” We present findings from a large scientific working group on research methods for clinical and population studies of dementia, which identified five categories of methodological challenges as follows: (1) attrition/sample selection, including selective survival; (2) measurement, including uncertainty in diagnostic criteria, measurement error in neuropsychological assessments, and practice or retest effects; (3) specification of longitudinal models when participants are followed for months, years, or even decades; (4) time-varying measurements; and (5) high-dimensional data. We explain why each challenge is important in dementia research and how it could compromise the translation of research findings into effective prevention or care strategies. We advance a checklist of potential sources of bias that should be routinely addressed when reporting dementia research. PMID:26397878

Methodological challenges of validating a clinical decision-making tool in the practice environment.

PubMed

Brennan, Caitlin W; Daly, Barbara J

2015-04-01

Validating a measurement tool intended for use in the practice environment poses challenges that may not be present when validating a tool intended solely for research purposes. The aim of this article is to describe the methodological challenges of validating a clinical decision-making tool, the Oncology Acuity Tool, which nurses use to make nurse assignment and staffing decisions prospectively each shift. Data were derived from a larger validation study, during which several methodological challenges arose. Revisions to the tool, including conducting iterative feedback cycles with end users, were necessary before the validation study was initiated. The "true" value of patient acuity is unknown, and thus, two approaches to inter-rater reliability assessment were used. Discordant perspectives existed between experts and end users. Balancing psychometric rigor with clinical relevance may be achieved through establishing research-practice partnerships, seeking active and continuous feedback with end users, and weighing traditional statistical rules of thumb with practical considerations. © The Author(s) 2014.

A systematic literature review of the key challenges for developing the structure of public health economic models.

PubMed

Squires, Hazel; Chilcott, James; Akehurst, Ronald; Burr, Jennifer; Kelly, Michael P

2016-04-01

To identify the key methodological challenges for public health economic modelling and set an agenda for future research. An iterative literature search identified papers describing methodological challenges for developing the structure of public health economic models. Additional multidisciplinary literature searches helped expand upon important ideas raised within the review. Fifteen articles were identified within the formal literature search, highlighting three key challenges: inclusion of non-healthcare costs and outcomes; inclusion of equity; and modelling complex systems and multi-component interventions. Based upon these and multidisciplinary searches about dynamic complexity, the social determinants of health, and models of human behaviour, six areas for future research were specified. Future research should focus on: the use of systems approaches within health economic modelling; approaches to assist the systematic consideration of the social determinants of health; methods for incorporating models of behaviour and social interactions; consideration of equity; and methodology to help modellers develop valid, credible and transparent public health economic model structures.

Empirical and pragmatic adequacy of grounded theory: Advancing nurse empowerment theory for nurses' practice.

PubMed

Udod, Sonia A; Racine, Louise

2017-12-01

To draw on the findings of a grounded theory study aimed at exploring how power is exercised in nurse-manager relationships in the hospital setting, this paper examines the empirical and pragmatic adequacy of grounded theory as a methodology to advance the concept of empowerment in the area of nursing leadership and management. The evidence on staff nurse empowerment has highlighted the magnitude of individual and organisational outcomes, but has not fully explicated the micro-level processes underlying how power is exercised, shared or created within the nurse-manager relationship. Although grounded theory is a widely adopted nursing research methodology, it remains less used in nursing leadership because of the dominance of quantitative approaches to research. Grounded theory methodology provides the empirical and pragmatic relevance to inform nursing practice and policy. Grounded theory is a relevant qualitative approach to use in leadership research as it provides a fine and detailed analysis of the process underlying complexity and bureaucracy. Discursive paper. A critical examination of the empirical and pragmatic relevance of grounded theory by (Corbin & Strauss, , ) as a method for analysing and solving problems in nurses' practice is provided. This paper provides evidence to support the empirical and pragmatic adequacy of grounded theory methodology. Although the application of the ontological, epistemological and methodological assumptions of grounded theory is challenging, this methodology is useful to address real-life problems in nursing practice by developing theoretical explanations of nurse empowerment, or lack thereof, in the workplace. Grounded theory represents a relevant methodology to inform nursing leadership research. Grounded theory is anchored in the reality of practice. The strength of grounded theory is to provide results that can be readily applied to clinical practice and policy as they arise from problems that affect practice and that are meaningful to nurses. © 2017 John Wiley & Sons Ltd.

Ethical and Legal Implications of the Methodological Crisis in Neuroimaging.

PubMed

Kellmeyer, Philipp

2017-10-01

Currently, many scientific fields such as psychology or biomedicine face a methodological crisis concerning the reproducibility, replicability, and validity of their research. In neuroimaging, similar methodological concerns have taken hold of the field, and researchers are working frantically toward finding solutions for the methodological problems specific to neuroimaging. This article examines some ethical and legal implications of this methodological crisis in neuroimaging. With respect to ethical challenges, the article discusses the impact of flawed methods in neuroimaging research in cognitive and clinical neuroscience, particularly with respect to faulty brain-based models of human cognition, behavior, and personality. Specifically examined is whether such faulty models, when they are applied to neurological or psychiatric diseases, could put patients at risk, and whether this places special obligations on researchers using neuroimaging. In the legal domain, the actual use of neuroimaging as evidence in United States courtrooms is surveyed, followed by an examination of ways that the methodological problems may create challenges for the criminal justice system. Finally, the article reviews and promotes some promising ideas and initiatives from within the neuroimaging community for addressing the methodological problems.

I. DEVELOPMENTAL METHODOLOGY AS A CENTRAL SUBDISCIPLINE OF DEVELOPMENTAL SCIENCE.

PubMed

Card, Noel A

2017-06-01

This first chapter introduces the main goals of the monograph and previews the remaining chapters. The goals of this monograph are to provide summaries of our current understanding of advanced developmental methodologies, provide information that can advance our understanding of human development, identify shortcomings in our understanding of developmental methodology, and serve as a flagpost for organizing developmental methodology as a subdiscipline within the broader field of developmental science. The remaining chapters in this monograph address issues in design (sampling and big data), longitudinal data analysis, and issues of replication and research accumulation. The final chapter describes the history of developmental methodology, considers how the previous chapters in this monograph fit within this subdiscipline, and offers recommendations for further advancement. © 2017 The Society for Research in Child Development, Inc.

Research priorities for multi-institutional collaborative research in surgical education.

PubMed

Stefanidis, Dimitrios; Cochran, Amalia; Sevdalis, Nick; Mellinger, John; Phitayakorn, Roy; Sullivan, Maura; Barney, Linda

2015-01-01

Research in surgical education has seen unprecedented growth but originates from single institutions and remains uncoordinated; this study aimed to generate a list of research priorities in surgical educational topics. The membership of the Association for Surgical Education was asked to submit up to 5 research questions concerned with multi-institutional collaborative surgical education research and to identify challenges faced by surgical education researchers. A modified Delphi methodology was used to create the research agenda based on these responses. Surgical educators responded to 3 survey rounds. Categories of submitted questions included teaching methods and curriculum development; assessment and competency; simulation; medical student preparation and selection; impact of work hour restrictions; and faculty development. Participants cited institutional culture and practice variability and lack of institutional review board coordination as common barriers to collaborative research, while identifying extensive planning, frequent communication, and availability of dedicated research coordinators as the most important facilitators. Using a Delphi methodology, a prioritized agenda for multi-institutional surgical education research was developed that may help advance surgeon education. Copyright © 2015 Elsevier Inc. All rights reserved.

Advanced Endoscopic Navigation: Surgical Big Data, Methodology, and Applications.

PubMed

Luo, Xiongbiao; Mori, Kensaku; Peters, Terry M

2018-06-04

Interventional endoscopy (e.g., bronchoscopy, colonoscopy, laparoscopy, cystoscopy) is a widely performed procedure that involves either diagnosis of suspicious lesions or guidance for minimally invasive surgery in a variety of organs within the body cavity. Endoscopy may also be used to guide the introduction of certain items (e.g., stents) into the body. Endoscopic navigation systems seek to integrate big data with multimodal information (e.g., computed tomography, magnetic resonance images, endoscopic video sequences, ultrasound images, external trackers) relative to the patient's anatomy, control the movement of medical endoscopes and surgical tools, and guide the surgeon's actions during endoscopic interventions. Nevertheless, it remains challenging to realize the next generation of context-aware navigated endoscopy. This review presents a broad survey of various aspects of endoscopic navigation, particularly with respect to the development of endoscopic navigation techniques. First, we investigate big data with multimodal information involved in endoscopic navigation. Next, we focus on numerous methodologies used for endoscopic navigation. We then review different endoscopic procedures in clinical applications. Finally, we discuss novel techniques and promising directions for the development of endoscopic navigation.

Crowd-Sourced Amputee Gait Data: A Feasibility Study Using YouTube Videos of Unilateral Trans-Femoral Gait.

PubMed

Gardiner, James; Gunarathne, Nuwan; Howard, David; Kenney, Laurence

2016-01-01

Collecting large datasets of amputee gait data is notoriously difficult. Additionally, collecting data on less prevalent amputations or on gait activities other than level walking and running on hard surfaces is rarely attempted. However, with the wealth of user-generated content on the Internet, the scope for collecting amputee gait data from alternative sources other than traditional gait labs is intriguing. Here we investigate the potential of YouTube videos to provide gait data on amputee walking. We use an example dataset of trans-femoral amputees level walking at self-selected speeds to collect temporal gait parameters and calculate gait asymmetry. We compare our YouTube data with typical literature values, and show that our methodology produces results that are highly comparable to data collected in a traditional manner. The similarity between the results of our novel methodology and literature values lends confidence to our technique. Nevertheless, clear challenges with the collection and interpretation of crowd-sourced gait data remain, including long term access to datasets, and a lack of validity and reliability studies in this area.

Crowd-Sourced Amputee Gait Data: A Feasibility Study Using YouTube Videos of Unilateral Trans-Femoral Gait

PubMed Central

Gardiner, James; Gunarathne, Nuwan; Howard, David; Kenney, Laurence

2016-01-01

Collecting large datasets of amputee gait data is notoriously difficult. Additionally, collecting data on less prevalent amputations or on gait activities other than level walking and running on hard surfaces is rarely attempted. However, with the wealth of user-generated content on the Internet, the scope for collecting amputee gait data from alternative sources other than traditional gait labs is intriguing. Here we investigate the potential of YouTube videos to provide gait data on amputee walking. We use an example dataset of trans-femoral amputees level walking at self-selected speeds to collect temporal gait parameters and calculate gait asymmetry. We compare our YouTube data with typical literature values, and show that our methodology produces results that are highly comparable to data collected in a traditional manner. The similarity between the results of our novel methodology and literature values lends confidence to our technique. Nevertheless, clear challenges with the collection and interpretation of crowd-sourced gait data remain, including long term access to datasets, and a lack of validity and reliability studies in this area. PMID:27764226

Strategies for the extraction and analysis of non-extractable polyphenols from plants.

PubMed

Domínguez-Rodríguez, Gloria; Marina, María Luisa; Plaza, Merichel

2017-09-08

The majority of studies based on phenolic compounds from plants are focused on the extractable fraction derived from an aqueous or aqueous-organic extraction. However, an important fraction of polyphenols is ignored due to the fact that they remain retained in the residue of extraction. They are the so-called non-extractable polyphenols (NEPs) which are high molecular weight polymeric polyphenols or individual low molecular weight phenolics associated to macromolecules. The scarce information available about NEPs shows that these compounds possess interesting biological activities. That is why the interest about the study of these compounds has been increasing in the last years. Furthermore, the extraction and characterization of NEPs are considered a challenge because the developed analytical methodologies present some limitations. Thus, the present literature review summarizes current knowledge of NEPs and the different methodologies for the extraction of these compounds, with a particular focus on hydrolysis treatments. Besides, this review provides information on the most recent developments in the purification, separation, identification and quantification of NEPs from plants. Copyright © 2017 Elsevier B.V. All rights reserved.

Intelligence for education: as described by Piaget and measured by psychometrics.

PubMed

Shayer, Michael

2008-03-01

Two separate paths to the concept of intelligence are discussed: the psychometric path being concerned with the measurement of intelligence, involving the methodology of norm-referenced testing; the path followed by Piaget, and others, addresses from the start the related question of how intelligence can be described, and employs a criterion-referenced methodology. The achievements of psychometrics are briefly described, with an argument that they now remain important tools of what Kuhn called 'normal science'. The criterion-referenced approach of Piaget and others is described, with evidence from intervention studies that the Genevan descriptions of children-in-action have allowed the choice of contexts within which children can profitably be challenged to go further in their thinking. Hence, Genevan psychology is also now a part of the normal science with important uses, shown both in neo-Piagetian studies and further research stemming from Geneva. Discussion of the 'Flynn effect' sheds light on both paths, with problems still unresolved. The argument is then developed that the relevance of neuroscience needs to be discussed to try to decide in what ways it may provide useful insights into intelligence.

Three-dimensional imaging of flat natural and cultural heritage objects by a Compton scattering modality

NASA Astrophysics Data System (ADS)

Guerrero Prado, Patricio; Nguyen, Mai K.; Dumas, Laurent; Cohen, Serge X.

2017-01-01

Characterization and interpretation of flat ancient material objects, such as those found in archaeology, paleoenvironments, paleontology, and cultural heritage, have remained a challenging task to perform by means of conventional x-ray tomography methods due to their anisotropic morphology and flattened geometry. To overcome the limitations of the mentioned methodologies for such samples, an imaging modality based on Compton scattering is proposed in this work. Classical x-ray tomography treats Compton scattering data as noise in the image formation process, while in Compton scattering tomography the conditions are set such that Compton data become the principal image contrasting agent. Under these conditions, we are able, first, to avoid relative rotations between the sample and the imaging setup, and second, to obtain three-dimensional data even when the object is supported by a dense material by exploiting backscattered photons. Mathematically this problem is addressed by means of a conical Radon transform and its inversion. The image formation process and object reconstruction model are presented. The feasibility of this methodology is supported by numerical simulations.

[SmartCare: automatizing clinical guidelines].

PubMed

Mersmann, Stefan

2009-10-01

In critical care environments, important medical and economic challenges are presented by the enhancement of therapeutic quality and the reduction of therapeutic costs. For this purpose, several clinical studies have demonstrated a positive impact of the adoption of so-called clinical guidelines. Clinical guidelines represent well documented best practices in healthcare and are fundamental aspects of evidence-based medicine. However, at the bedside, such clinical guidelines remain difficult to use by clinical staff. The knowledge-based technology SmartCare allows incorporation of arbitrary computerized clinical guidelines into various medical target systems. SmartCare constitutes a clinical guideline engine because it executes one or more clinical guidelines on a specific medical device. SmartCare was initially applied for the automated control of a mechanical ventilator to assist the process of weaning from a medical device. The methodology allows further applications to be implemented effectively with other medical devices and/or with other appropriate guidelines. In this paper, we report on the methodology and the resulting versatility of such a system, as well as the clinical evaluation of SmartCare/PS and its perspectives.

Methods for handling uncertainty within pharmaceutical funding decisions

NASA Astrophysics Data System (ADS)

Stevenson, Matt; Tappenden, Paul; Squires, Hazel

2014-01-01

This article provides a position statement regarding decision making under uncertainty within the economic evaluation of pharmaceuticals, with a particular focus upon the National Institute for Health and Clinical Excellence context within England and Wales. This area is of importance as funding agencies have a finite budget from which to purchase a selection of competing health care interventions. The objective function generally used is that of maximising societal health with an explicit acknowledgement that there will be opportunity costs associated with purchasing a particular intervention. Three components of uncertainty are discussed within a pharmaceutical funding perspective: methodological uncertainty, parameter uncertainty and structural uncertainty, alongside a discussion of challenges that are particularly pertinent to health economic evaluation. The discipline has focused primarily on handling methodological and parameter uncertainty and a clear reference case has been developed for consistency across evaluations. However, uncertainties still remain. Less attention has been given to methods for handling structural uncertainty. The lack of adequate methods to explicitly incorporate this aspect of model development may result in the true uncertainty surrounding health care investment decisions being underestimated. Research in this area is ongoing as we review.

Autogrid-based clustering of kinases: selection of representative conformations for docking purposes.

PubMed

Marzaro, Giovanni; Ferrarese, Alessandro; Chilin, Adriana

2014-08-01

The selection of the most appropriate protein conformation is a crucial aspect in molecular docking experiments. In order to reduce the errors arising from the use of a single protein conformation, several authors suggest the use of several tridimensional structures for the target. However, the selection of the most appropriate protein conformations still remains a challenging goal. The protein 3D-structures selection is mainly performed based on pairwise root-mean-square-deviation (RMSD) values computation, followed by hierarchical clustering. Herein we report an alternative strategy, based on the computation of only two atom affinity map for each protein conformation, followed by multivariate analysis and hierarchical clustering. This methodology was applied on seven different kinases of pharmaceutical interest. The comparison with the classical RMSD-based strategy was based on cross-docking of co-crystallized ligands. In the case of epidermal growth factor receptor kinase, also the docking performance on 220 known ligands were evaluated, followed by 3D-QSAR studies. In all the cases, the herein proposed methodology outperformed the RMSD-based one.

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

PubMed

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

2018-01-01

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

Online professionalism: A synthetic review.

PubMed

Chretien, Katherine C; Tuck, Matthew G

2015-04-01

The rise of social media has increased connectivity and blurred personal and professional boundaries, bringing new challenges for medical professionalism. Whether traditional professionalism principles apply to the online social media space remains unknown. The purpose of this synthetic literature review was to characterize the original peer-reviewed research studies published between 1 January 2000-1 November 2014 on online professionalism, to assess methodologies and approaches used, and to provide insights to guide future studies in this area. The investigators searched three databases and performed manual searches of bibliographies to identify the 32 studies included. Most studies originated in the USA. Cross-sectional surveys and analyses of publicly available online content were the most common methodologies employed. Studies covered the general areas of use and privacy, assessment of unprofessional online behaviours, consensus-gathering of what constitutes unprofessional or inappropriate online behaviours, and education and policies. Studies were of variable quality; only around half of survey studies had response rates of 50% or greater. Medical trainees were the most common population studied. Future directions for research include public perspectives of online professionalism, impact on patient trust, and how to use social media productively as medical professionals.

Conducting Indigenous Research in Western Knowledge Spaces: Aligning Theory and Methodology

ERIC Educational Resources Information Center

Singh, Myra; Major, Jae

2017-01-01

Walking simultaneously in two worlds as an Indigenous researcher, navigating Indigenous and Western epistemologies/methodologies can have its challenges. Indigenous methodologies have become an important element of qualitative research and have been increasingly taken up by both Indigenous and non-Indigenous researchers. Indigenous methodologies…

Emergent Pedagogy and Affect in Collaborative Research: A Metho-Pedagogical Paradigm

ERIC Educational Resources Information Center

Gallagher, Kathleen; Wessels, Anne

2011-01-01

The widespread turn towards "collaboration" in qualitative research methodologies warrants careful and continuous critique. This paper addresses the possibilities and the challenges of collaborative methodology, and in particular what happens when the line between pedagogy and methodology is blurred in classroom-based ethnographic…

Size analysis of polyglutamine protein aggregates using fluorescence detection in an analytical ultracentrifuge.

PubMed

Polling, Saskia; Hatters, Danny M; Mok, Yee-Foong

2013-01-01

Defining the aggregation process of proteins formed by poly-amino acid repeats in cells remains a challenging task due to a lack of robust techniques for their isolation and quantitation. Sedimentation velocity methodology using fluorescence detected analytical ultracentrifugation is one approach that can offer significant insight into aggregation formation and kinetics. While this technique has traditionally been used with purified proteins, it is now possible for substantial information to be collected with studies using cell lysates expressing a GFP-tagged protein of interest. In this chapter, we describe protocols for sample preparation and setting up the fluorescence detection system in an analytical ultracentrifuge to perform sedimentation velocity experiments on cell lysates containing aggregates formed by poly-amino acid repeat proteins.

Deformation in Metallic Glass: Connecting Atoms to Continua

NASA Astrophysics Data System (ADS)

Hinkle, Adam R.; Falk, Michael L.; Rycroft, Chris H.; Shields, Michael D.

Metallic glasses like other amorphous solids experience strain localization as the primary mode of failure. However, the development of continuum constitutive laws which provide a quantitative description of disorder and mechanical deformation remains an open challenge. Recent progress has shown the necessity of accurately capturing fluctuations in material structure, in particular the statistical changes in potential energy of the atomic constituents during the non-equilibrium process of applied shear. Here we directly cross-compare molecular dynamics shear simulations of a ZrCu glass with continuum shear transformation zone (STZ) theory representations. We present preliminary results for a methodology to coarse-grain detailed molecular dynamics data with the goal of initializing a continuum representation in the STZ theory. NSF Grants Awards 1107838, 1408685, and 0801471.

Efficient Fabrication of Nanoporous Si and Si/Ge Enabled by a Heat Scavenger in Magnesiothermic Reactions

PubMed Central

Luo, Wei; Wang, Xingfeng; Meyers, Colin; Wannenmacher, Nick; Sirisaksoontorn, Weekit; Lerner, Michael M.; Ji, Xiulei

2013-01-01

Magnesiothermic reduction can directly convert SiO2 into Si nanostructures. Despite intense efforts, efficient fabrication of highly nanoporous silicon by Mg still remains a significant challenge due to the exothermic reaction nature. By employing table salt (NaCl) as a heat scavenger for the magnesiothermic reduction, we demonstrate an effective route to convert diatom (SiO2) and SiO2/GeO2 into nanoporous Si and Si/Ge composite, respectively. Fusion of NaCl during the reaction consumes a large amount of heat that otherwise collapses the nano-porosity of products and agglomerates silicon domains into large crystals. Our methodology is potentially competitive for a practical production of nanoporous Si-based materials. PMID:23860418

Efficient fabrication of nanoporous si and Si/Ge enabled by a heat scavenger in magnesiothermic reactions.

PubMed

Luo, Wei; Wang, Xingfeng; Meyers, Colin; Wannenmacher, Nick; Sirisaksoontorn, Weekit; Lerner, Michael M; Ji, Xiulei

2013-01-01

Magnesiothermic reduction can directly convert SiO2 into Si nanostructures. Despite intense efforts, efficient fabrication of highly nanoporous silicon by Mg still remains a significant challenge due to the exothermic reaction nature. By employing table salt (NaCl) as a heat scavenger for the magnesiothermic reduction, we demonstrate an effective route to convert diatom (SiO2) and SiO2/GeO2 into nanoporous Si and Si/Ge composite, respectively. Fusion of NaCl during the reaction consumes a large amount of heat that otherwise collapses the nano-porosity of products and agglomerates silicon domains into large crystals. Our methodology is potentially competitive for a practical production of nanoporous Si-based materials.

Neonatal Neurobehavioral and Neuroanatomic Correlates of Prenatal Cocaine Exposure

PubMed Central

FRANK, DEBORAH A.; AUGUSTYN, MARILYN; ZUCKERMAN, BARRY S.

2008-01-01

Complex methodologic challenges face researchers studying the effects of prenatal cocaine exposure on infant outcome. These include unavoidable imprecision in ascertaining the gestational timing and dose of cocaine to which the fetus was exposed and difficulties in identifying and quantifying the confounding, mediating, and moderating variables. Review of research on neonatal behavioral and cranial ultrasound findings following in utero cocaine exposure is used to illustrate these issues. We conclude that there are measurable but not dramatic dose-related effects of prenatal cocaine exposure on infant central nervous system structure and function. The effects of dose of prenatal cocaine exposure on later child development remain to be determined. Such research would be facilitated by a scientific consensus delineating relative doses of prenatal cocaine exposure. PMID:9668396

CAGE IIIA Distributed Simulation Design Methodology

DTIC Science & Technology

2014-05-01

2 VHF Very High Frequency VLC Video LAN Codec – an Open-source cross-platform multimedia player and framework VM Virtual Machine VOIP Voice Over...Implementing Defence Experimentation (GUIDEx). The key challenges for this methodology are with understanding how to: • design it o define the...operation and to be available in the other nation’s simulations. The challenge for the CAGE campaign of experiments is to continue to build upon this

Opportunities and Challenges in Establishing a Cohort Study: An Example From Cleft Lip/Palate Research in the United Kingdom.

PubMed

Stock, Nicola Marie; Humphries, Kerry; Pourcain, Beate St; Bailey, Maggie; Persson, Martin; Ho, Karen M; Ring, Susan; Marsh, Cathy; Albery, Liz; Rumsey, Nichola; Sandy, Jonathan

2016-05-01

Cleft lip and/or palate (CL/P) is one of the most common birth conditions in the world, but little is known about its causes. Professional opinion remains divided as to which treatments may be the most beneficial for patients with CL/P, and the factors that contribute to psychological adjustment are poorly understood. The use of different methodological approaches and tools plays a key role in hampering efforts to address discrepancies within the evidence base. A new UK-wide program of research, The Cleft Collective, was established to combat many of these methodological challenges and to address some of the key research questions important to all CL/P stakeholders. To describe the establishment of CL/P cohort studies in the United Kingdom and to consider the many opportunities this resource will generate. To date, protocols have been developed and implemented within most UK cleft teams. Biological samples, environmental information, and data pertaining to parental psychological well-being and child development are being collected successfully. Recruitment is currently on track to meet the ambitious target of approximately 9800 individuals from just more than 3000 families. The Cleft Collective cohort studies represent a significant step forward for research in the field of CL/P. The data collected will form a comprehensive resource of information about individuals with CL/P and their families. This resource will provide the basis for many future projects and collaborations, both in the United Kingdom and around the world.

Sources of Safety Data and Statistical Strategies for Design and Analysis: Transforming Data Into Evidence.

PubMed

Ma, Haijun; Russek-Cohen, Estelle; Izem, Rima; Marchenko, Olga V; Jiang, Qi

2018-03-01

Safety evaluation is a key aspect of medical product development. It is a continual and iterative process requiring thorough thinking, and dedicated time and resources. In this article, we discuss how safety data are transformed into evidence to establish and refine the safety profile of a medical product, and how the focus of safety evaluation, data sources, and statistical methods change throughout a medical product's life cycle. Some challenges and statistical strategies for medical product safety evaluation are discussed. Examples of safety issues identified in different periods, that is, premarketing and postmarketing, are discussed to illustrate how different sources are used in the safety signal identification and the iterative process of safety assessment. The examples highlighted range from commonly used pediatric vaccine given to healthy children to medical products primarily used to treat a medical condition in adults. These case studies illustrate that different products may require different approaches, and once a signal is discovered, it could impact future safety assessments. Many challenges still remain in this area despite advances in methodologies, infrastructure, public awareness, international harmonization, and regulatory enforcement. Innovations in safety assessment methodologies are pressing in order to make the medical product development process more efficient and effective, and the assessment of medical product marketing approval more streamlined and structured. Health care payers, providers, and patients may have different perspectives when weighing in on clinical, financial and personal needs when therapies are being evaluated.

Microparticle Analysis in Disorders of Hemostasis and Thrombosis

PubMed Central

Mooberry, Micah J.; Key, Nigel S.

2015-01-01

Microparticles (MPs) are submicron vesicles released from the plasma membrane of eukaryotic cells in response to activation or apoptosis. MPs are known to be involved in numerous biologic processes, including inflammation, the immune response, cancer metastasis, and angiogenesis. Their earliest recognized and most widely accepted role, however, is the ability to promote and support the process of blood coagulation. Consequently, there is ongoing interest in studying MPs in disorders of hemostasis and thrombosis. Both phosphatidylserine (PS) exposure and the presence of tissue factor (TF) in the MP membrane may account for their procoagulant properties, and elevated numbers of MPs in plasma have been reported in numerous prothrombotic conditions. To date, however, there are few data on true causality linking MPs to the genesis of thrombosis. A variety of methodologies have been employed to characterize and quantify MPs, although detection is challenging due to their submicron size. Flow cytometry (FCM) remains the most frequently utilized strategy for MP detection; however, it is associated with significant technological limitations. Additionally, pre-analytical and analytical variables can influence the detection of MPs by FCM, rendering data interpretation difficult. Lack of methodologic standardization in MP analysis by FCM confounds the issue further, although efforts are currently underway to address this limitation. Moving forward, it will be important to address these technical challenges as a scientific community if we are to better understand the role that MPs play in disorders of hemostasis and thrombosis. PMID:25704723

Evaluating web-based cognitive-affective remediation in recent trauma survivors: study rationale and protocol.

PubMed

Fine, Naomi B; Achituv, Michal; Etkin, Amit; Merin, Ofer; Shalev, Arieh Y

2018-01-01

Background : The immediate aftermath of traumatic events is a period of enhanced neural plasticity, following which some survivors remain with post-traumatic stress disorder (PTSD) whereas others recover. Evidence points to impairments in emotional reactivity, emotion regulation, and broader executive functions as critically contributing to PTSD. Emerging evidence further suggests that the neural mechanisms underlying these functions remain plastic in adulthood and that targeted retraining of these systems may enhance their efficiency and could reduce the likelihood of developing PTSD. Administering targeted neurocognitive training shortly after trauma exposure is a daunting challenge. This work describes a study design addressing that challenge. The study evaluated the direct effects of cognitive remediation training on neurocognitive mechanisms that hypothetically underlay PTSD, and the indirect effect of this intervention on emerging PTSD symptoms. Method : We describe a study rationale, design, and methodological choices involving: (a) participants' enrolment; (b) implementation and management of a daily self-administered, web-based intervention; (c) reliable, timely screening and assessment of treatment of eligible survivors; and (d) defining control conditions and outcome measures. We outline the rationale of choices made regarding study sample, timing of intervention, measurements, monitoring participants' adherence, and ways to harmonize and retain interviewers' fidelity and mitigate eventual burnout by repeated contacts with recently traumatized survivors. Conclusion : Early web-based interventions targeting causative mechanisms of PTSD can be informed by the model presented in this paper.

Postgraduate Conception of Research Methodology: Implications for Learning and Teaching

ERIC Educational Resources Information Center

Daniel, Ben; Kumar, Vijay; Omar, Noritah

2018-01-01

This qualitative inquiry investigates postgraduate students' conceptions of research methodology and how it contributes to their learning. It explores factors likely to motivate student choice of research methodology and challenges in understanding research methods. The research was carried out at research-intensive universities in New Zealand and…

Establishing Equivalence: Methodological Progress in Group-Matching Design and Analysis

ERIC Educational Resources Information Center

Kover, Sara T.; Atwood, Amy K.

2013-01-01

This methodological review draws attention to the challenges faced by intellectual and developmental disabilities researchers in the appropriate design and analysis of group comparison studies. We provide a brief overview of matching methodologies in the field, emphasizing group-matching designs used in behavioral research on cognition and…

The Advantages and Challenges of Unannounced Standardized Patients Methodology to Assess Healthcare Communication

PubMed Central

Siminoff, Laura A.; Rogers, Heather L.; Waller, Allison C.; Harris-Haywood, Sonja; Esptein, Ronald M.; Borrell Carrio, Francesc; Gliva-McConvey, Gayle; Longo, Daniel R.

2011-01-01

Objective This paper provides an overview of the implementation of using Unannounced Standardized Patients (USPs) to conduct health communication research in clinical settings. Methods Certain types of health communication situations are difficult to capture because of their rarity or unpredictable nature. In primary care the real reasons for a visit are frequently unknown until the consultation is well under way. Therefore, it is logistically difficult for communication studies to capture many real-time communications between patients and their physicians. Although the USP methodology is ideal for capturing these communication behaviors, challenges to using this method include developing collaborative relationships with clinical practices, logistical issues such as safeguarding the identity of the USP, training USPs and creating their identities, maintaining fidelity to the role, and analyzing the resultant data. Results This paper discusses the challenges and solutions to USP implementation. We provide an example of how to implement a USP study using an on-going study being conducted in primary care practices. Conclusion This paper explores the advantages and challenges as well as strategies to overcome obstacles to implementing a USP study. Practice Implications Despite the challenges, USP methodology can contribute much to our understanding of health communication and practice. PMID:21316182

A proposed reductionist solution to address the methodological challenges of inconsistent reflexology maps and poor experimental controls in reflexology research: a discussion paper.

PubMed

Jones, Jenny; Thomson, Patricia; Lauder, William; Leslie, Stephen J

2013-03-01

Reflexology is a complex massage intervention, based on the concept that specific areas of the feet (reflex points) correspond to individual internal organs within the body. Reflexologists trained in the popular Ingham reflexology method claim that massage to these points, using massage techniques unique to reflexology, stimulates an increase in blood supply to the corresponding organ. Reflexology researchers face two key methodological challenges that need to be addressed if a specific treatment-related hemodynamic effect is to be scientifically demonstrated. The first is the problem of inconsistent reflexology foot maps; the second is the issue of poor experimental controls. This article proposes a potential experimental solution that we believe can address both methodological challenges and in doing so, allow any specific hemodynamic treatment effect unique to reflexology to experimentally reveal itself.

Post-traumatic Stress Symptoms in Post-ICU Family Members: Review and Methodological Challenges

PubMed Central

Petrinec, Amy B.; Daly, Barbara J.

2018-01-01

Family members of intensive care unit (ICU) patients are at risk for symptoms of post-traumatic stress disorder (PTSD) following ICU discharge. The aim of this systematic review is to examine the current literature regarding post-ICU family PTSD symptoms with an emphasis on methodological issues in conducting research on this challenging phenomenon. An extensive review of the literature was performed confining the search to English language studies reporting PTSD symptoms in adult family members of adult ICU patients. Ten studies were identified for review published from 2004–2012. Findings demonstrate a significant prevalence of family PTSD symptoms in the months following ICU hospitalization. However, there are several methodological challenges to the interpretation of existing studies and to the conduct of future research including differences in sampling, identification of risk factors and covariates of PTSD, and lack of consensus regarding the most appropriate PTSD symptom measurement tools and timing. PMID:25061017

A method comparison of photovoice and content analysis: research examining challenges and supports of family caregivers.

PubMed

Faucher, Mary Ann; Garner, Shelby L

2015-11-01

The purpose of this manuscript is to compare methods and thematic representations of the challenges and supports of family caregivers identified with photovoice methodology contrasted with content analysis, a more traditional qualitative approach. Results from a photovoice study utilizing a participatory action research framework was compared to an analysis of the audio-transcripts from that study utilizing content analysis methodology. Major similarities between the results are identified with some notable differences. Content analysis provides a more in-depth and abstract elucidation of the nature of the challenges and supports of the family caregiver. The comparison provides evidence to support the trustworthiness of photovoice methodology with limitations identified. The enhanced elaboration of theme and categories with content analysis may have some advantages relevant to the utilization of this knowledge by health care professionals. Copyright © 2015 Elsevier Inc. All rights reserved.

Identification and Forecasting in Mortality Models

PubMed Central

Nielsen, Jens P.

2014-01-01

Mortality models often have inbuilt identification issues challenging the statistician. The statistician can choose to work with well-defined freely varying parameters, derived as maximal invariants in this paper, or with ad hoc identified parameters which at first glance seem more intuitive, but which can introduce a number of unnecessary challenges. In this paper we describe the methodological advantages from using the maximal invariant parameterisation and we go through the extra methodological challenges a statistician has to deal with when insisting on working with ad hoc identifications. These challenges are broadly similar in frequentist and in Bayesian setups. We also go through a number of examples from the literature where ad hoc identifications have been preferred in the statistical analyses. PMID:24987729

Barriers and facilitators to recruitment of physicians and practices for primary care health services research at one centre.

PubMed

Johnston, Sharon; Liddy, Clare; Hogg, William; Donskov, Melissa; Russell, Grant; Gyorfi-Dyke, Elizabeth

2010-12-13

While some research has been conducted examining recruitment methods to engage physicians and practices in primary care research, further research is needed on recruitment methodology as it remains a recurrent challenge and plays a crucial role in primary care research. This paper reviews recruitment strategies, common challenges, and innovative practices from five recent primary care health services research studies in Ontario, Canada. We used mixed qualitative and quantitative methods to gather data from investigators and/or project staff from five research teams. Team members were interviewed and asked to fill out a brief survey on recruitment methods, results, and challenges encountered during a recent or ongoing project involving primary care practices or physicians. Data analysis included qualitative analysis of interview notes and descriptive statistics generated for each study. Recruitment rates varied markedly across the projects despite similar initial strategies. Common challenges and creative solutions were reported by many of the research teams, including building a sampling frame, developing front-office rapport, adapting recruitment strategies, promoting buy-in and interest in the research question, and training a staff recruiter. Investigators must continue to find effective ways of reaching and involving diverse and representative samples of primary care providers and practices by building personal connections with, and buy-in from, potential participants. Flexible recruitment strategies and an understanding of the needs and interests of potential participants may also facilitate recruitment.

An evaluation of the effectiveness of a case-specific approach to challenging behaviour associated with dementia.

PubMed

Bird, Michael; Llewellyn-Jones, Robert H; Korten, Ailsa

2009-01-01

Treatment of challenging behaviour in dementia using standardized psychopharmacological or psychosocial approaches remains problematical. A case-specific approach was trialled in this study, based on extensive evidence that each case is different in aetiology, the effects of the behaviour on others and what interventions are possible given the available resources. Forty-four consecutive referrals for challenging behaviour (two-thirds in residential care) were assessed across multiple causal domains. Both assessment and development of interventions were undertaken in collaboration with family carers and care staff. Measures of behaviour and associated carer distress, as well as medication and service use, were taken pre-intervention and at 2- and 5-month follow-ups. Psychotropic medication was used with a minority of participants but, overall, antipsychotic use was reduced. Psychosocial methods predominated, with 77% of cases judged as mainly or entirely psychosocial by an expert panel. There were significant mean improvements in behaviour and carer distress. Using conservative criteria there was a 65.9% clinical success rate. Results confirm those of other studies which have used multifaceted interventions tailored to the unique needs of each case. They compare favourably with results from trials of standardized psycho-pharmacological or psychosocial approaches. More trials are needed, necessarily involving further development of robust methodologies which reflect the case-specific nature of challenging behaviour associated with dementia.

Guidelines for reporting methodological challenges and evaluating potential bias in dementia research.

PubMed

Weuve, Jennifer; Proust-Lima, Cécile; Power, Melinda C; Gross, Alden L; Hofer, Scott M; Thiébaut, Rodolphe; Chêne, Geneviève; Glymour, M Maria; Dufouil, Carole

2015-09-01

Clinical and population research on dementia and related neurologic conditions, including Alzheimer's disease, faces several unique methodological challenges. Progress to identify preventive and therapeutic strategies rests on valid and rigorous analytic approaches, but the research literature reflects little consensus on "best practices." We present findings from a large scientific working group on research methods for clinical and population studies of dementia, which identified five categories of methodological challenges as follows: (1) attrition/sample selection, including selective survival; (2) measurement, including uncertainty in diagnostic criteria, measurement error in neuropsychological assessments, and practice or retest effects; (3) specification of longitudinal models when participants are followed for months, years, or even decades; (4) time-varying measurements; and (5) high-dimensional data. We explain why each challenge is important in dementia research and how it could compromise the translation of research findings into effective prevention or care strategies. We advance a checklist of potential sources of bias that should be routinely addressed when reporting dementia research. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Complexity Thinking and Methodology: The Potential of "Complex Case Study" for Educational Research

ERIC Educational Resources Information Center

Hetherington, Lindsay

2013-01-01

Complexity theories have in common perspectives that challenge linear methodologies and views of causality. In educational research, relatively little has been written explicitly exploring their implications for educational research methodology in general and case study in particular. In this paper, I offer a rationale for case study as a research…

Taking a Distributed Perspective: Epistemological and Methodological Tradeoffs in Operationalizing the Leader-Plus Aspect

ERIC Educational Resources Information Center

Spillane, James P.; Camburn, Eric M.; Pustejovsky, James; Pareja, Amber Stitziel; Lewis, Geoff

2008-01-01

Purpose: This paper is concerned with the epistemological and methodological challenges involved in studying the distribution of leadership across people within the school--the leader-plus aspect of a distributed perspective, which it aims to investigate. Design/methodology/approach: The paper examines the entailments of the distributed…

Can cultural differences lead to accidents? Team cultural differences and sociotechnical system operations.

PubMed

Strauch, Barry

2010-04-01

I discuss cultural factors and how they may influence sociotechnical system operations. Investigations of several major transportation accidents suggest that cultural factors may have played a role in the causes of the accidents. However, research has not fully addressed how cultural factors can influence sociotechnical systems. I review literature on cultural differences in general and cultural factors in sociotechnical systems and discuss how these differences can affect team performance in sociotechnical systems. Cultural differences have been observed in social and interpersonal dimensions and in cognitive and perceptual styles; these differences can affect multioperator team performance. Cultural factors may account for team errors in sociotechnical systems, most likely during high-workload, high-stress operational phases. However, much of the research on cultural factors has methodological and interpretive shortcomings that limit their applicability to sociotechnical systems. Although some research has been conducted on the role of cultural differences on team performance in sociotechnical system operations, considerable work remains to be done before the effects of these differences can be fully understood. I propose a model that illustrates how culture can interact with sociotechnical system operations and suggest avenues of future research. Given methodological challenges in measuring cultural differences and team performance in sociotechnical system operations, research in these systems should use a variety of methodologies to better understand how culture can affect multioperator team performance in these systems.

Screening for Triterpenoid Saponins in Plants Using Hyphenated Analytical Platforms.

PubMed

Khakimov, Bekzod; Tseng, Li Hong; Godejohann, Markus; Bak, Søren; Engelsen, Søren Balling

2016-11-24

Recently the number of studies investigating triterpenoid saponins has drastically increased due to their diverse and potentially attractive biological activities. Currently the literature contains chemical structures of few hundreds of triterpenoid saponins of plant and animal origin. Triterpenoid saponins consist of a triterpene aglycone with one or more sugar moieties attached to it. However, due to similar physico-chemical properties, isolation and identification of a large diversity of triterpenoid saponins remain challenging. This study demonstrates a methodology to screen saponins using hyphenated analytical platforms, GC-MS, LC-MS/MS, and LC-SPE-NMR/MS, in the example of two different phenotypes of the model plant Barbarea vulgaris (winter cress), glabrous (G) and pubescent (P) type that are known to differ by their insect resistance. The proposed methodology allows for detailed comparison of saponin profiles from intact plant extracts as well as saponin aglycone profiles from hydrolysed samples. Continuously measured 1D proton NMR data during LC separation along with mass spectrometry data revealed significant differences, including contents of saponins, types of aglycones and numbers of sugar moieties attached to the aglycone. A total of 49 peaks were tentatively identified as saponins from both plants; they are derived from eight types of aglycones and with 2-5 sugar moieties. Identification of two previously known insect-deterrent saponins, hederagenin cellobioside and oleanolic acid cellobioside, demonstrated the applicability of the methodology for relatively rapid screening of bioactive compounds.

Randomized controlled trials of simulation-based interventions in Emergency Medicine: a methodological review.

PubMed

Chauvin, Anthony; Truchot, Jennifer; Bafeta, Aida; Pateron, Dominique; Plaisance, Patrick; Yordanov, Youri

2018-04-01

The number of trials assessing Simulation-Based Medical Education (SBME) interventions has rapidly expanded. Many studies show that potential flaws in design, conduct and reporting of randomized controlled trials (RCTs) can bias their results. We conducted a methodological review of RCTs assessing a SBME in Emergency Medicine (EM) and examined their methodological characteristics. We searched MEDLINE via PubMed for RCT that assessed a simulation intervention in EM, published in 6 general and internal medicine and in the top 10 EM journals. The Cochrane Collaboration risk of Bias tool was used to assess risk of bias, intervention reporting was evaluated based on the "template for intervention description and replication" checklist, and methodological quality was evaluated by the Medical Education Research Study Quality Instrument. Reports selection and data extraction was done by 2 independents researchers. From 1394 RCTs screened, 68 trials assessed a SBME intervention. They represent one quarter of our sample. Cardiopulmonary resuscitation (CPR) is the most frequent topic (81%). Random sequence generation and allocation concealment were performed correctly in 66 and 49% of trials. Blinding of participants and assessors was performed correctly in 19 and 68%. Risk of attrition bias was low in three-quarters of the studies (n = 51). Risk of selective reporting bias was unclear in nearly all studies. The mean MERQSI score was of 13.4/18.4% of the reports provided a description allowing the intervention replication. Trials assessing simulation represent one quarter of RCTs in EM. Their quality remains unclear, and reproducing the interventions appears challenging due to reporting issues.

Methodological issues associated with preclinical drug development and increased placebo effects in schizophrenia clinical trials.

PubMed

Brown, Matt A; Bishnoi, Ram J; Dholakia, Sara; Velligan, Dawn I

2016-01-20

Recent failures to detect efficacy in clinical trials investigating pharmacological treatments for schizophrenia raise concerns regarding the potential contribution of methodological shortcomings to this research. This review provides an examination of two key methodological issues currently suspected of playing a role in hampering schizophrenia drug development; 1) limitations on the translational utility of preclinical development models, and 2) methodological challenges posed by increased placebo effects. Recommendations for strategies to address these methodological issues are addressed.

Understanding Participatory Action Research: A Qualitative Research Methodology Option

ERIC Educational Resources Information Center

MacDonald, Cathy

2012-01-01

Participatory Action Research (PAR) is a qualitative research methodology option that requires further understanding and consideration. PAR is considered democratic, equitable, liberating, and life-enhancing qualitative inquiry that remains distinct from other qualitative methodologies (Kach & Kralik, 2006). Using PAR, qualitative features of an…

The Challenges of Human Resource Management towards Organizational Effectiveness: A Comparative Study in Southern EU

ERIC Educational Resources Information Center

Stavrou-Costea, Eleni

2005-01-01

Purpose: The study aims to examine the human resource management challenges in Southern EU and their effect on organizational performance. Design/methodology/approach: First, key challenges were identified in the existing literature. Then, these challenges were matched with those reported most often in the CRANET questionnaire. These challenges…

HIV Risks, Testing, and Treatment in the Former Soviet Union: Challenges and Future Directions in Research and Methodology.

PubMed

Saadat, Victoria M

2015-01-01

The dissolution of the USSR resulted in independence for constituent republics but left them battling an unstable economic environment and healthcare. Increases in injection drug use, prostitution, and migration were all widespread responses to this transition and have contributed to the emergence of an HIV epidemic in the countries of former Soviet Union. Researchers have begun to identify the risks of HIV infection as well as the barriers to HIV testing and treatment in the former Soviet Union. Significant methodological challenges have arisen and need to be addressed. The objective of this review is to determine common threads in HIV research in the former Soviet Union and provide useful recommendations for future research studies. In this systematic review of the literature, Pubmed was searched for English-language studies using the key search terms "HIV", "AIDS", "human immunodeficiency virus", "acquired immune deficiency syndrome", "Central Asia", "Kazakhstan", "Kyrgyzstan", "Uzbekistan", "Tajikistan", "Turkmenistan", "Russia", "Ukraine", "Armenia", "Azerbaijan", and "Georgia". Studies were evaluated against eligibility criteria for inclusion. Thirty-nine studies were identified across the two main topic areas of HIV risk and barriers to testing and treatment, themes subsequently referred to as "risk" and "barriers". Study design was predominantly cross-sectional. The most frequently used sampling methods were peer-to-peer and non-probabilistic sampling. The most frequently reported risks were condom misuse, risky intercourse, and unsafe practices among injection drug users. Common barriers to testing included that testing was inconvenient, and that results would not remain confidential. Frequent barriers to treatment were based on a distrust in the treatment system. The findings of this review reveal methodological limitations that span the existing studies. Small sample size, cross-sectional design, and non-probabilistic sampling methods were frequently reported limitations. Future work is needed to examine barriers to testing and treatment as well as longitudinal studies on HIV risk over time in most-at-risk populations.

Development and Validation of a New Air Carrier Block Time Prediction Model and Methodology

NASA Astrophysics Data System (ADS)

Litvay, Robyn Olson

Commercial airline operations rely on predicted block times as the foundation for critical, successive decisions that include fuel purchasing, crew scheduling, and airport facility usage planning. Small inaccuracies in the predicted block times have the potential to result in huge financial losses, and, with profit margins for airline operations currently almost nonexistent, potentially negate any possible profit. Although optimization techniques have resulted in many models targeting airline operations, the challenge of accurately predicting and quantifying variables months in advance remains elusive. The objective of this work is the development of an airline block time prediction model and methodology that is practical, easily implemented, and easily updated. Research was accomplished, and actual U.S., domestic, flight data from a major airline was utilized, to develop a model to predict airline block times with increased accuracy and smaller variance in the actual times from the predicted times. This reduction in variance represents tens of millions of dollars (U.S.) per year in operational cost savings for an individual airline. A new methodology for block time prediction is constructed using a regression model as the base, as it has both deterministic and probabilistic components, and historic block time distributions. The estimation of the block times for commercial, domestic, airline operations requires a probabilistic, general model that can be easily customized for a specific airline’s network. As individual block times vary by season, by day, and by time of day, the challenge is to make general, long-term estimations representing the average, actual block times while minimizing the variation. Predictions of block times for the third quarter months of July and August of 2011 were calculated using this new model. The resulting, actual block times were obtained from the Research and Innovative Technology Administration, Bureau of Transportation Statistics (Airline On-time Performance Data, 2008-2011) for comparison and analysis. Future block times are shown to be predicted with greater accuracy, without exception and network-wide, for a major, U.S., domestic airline.

Clinical Laboratory Evaluation of Electronic Cigarettes/Electronic Nicotine Delivery Systems: Methodological Challenges

PubMed Central

Blank, Melissa D.; Breland, Alison B.; Cobb, Caroline O.; Spindle, Tory; Ramôa, Carolina; Eissenberg, Thomas

2017-01-01

Objective Evaluating electronic cigarettes (ECIGs) in the clinical laboratory is critical to understanding their effects. However, laboratory evaluation of ECIGs can be challenging, as they are a novel, varied, and evolving class of products. The objective of this paper is to describe some methodological challenges to the clinical laboratory evaluation of ECIGs. Methods The authors gathered information about challenges involved in the laboratory evaluation of ECIGs. Challenges were categorized and solutions provided when possible. Results Methods used to study combustible cigarettes may need to be adapted to account for ECIG novelty and differences within the class. Challenges to ECIG evaluation can include issues related to 1) identification of ECIG devices and liquids, 2) determination of short -term ECIG abstinence, 3) measurement of use behavior, and 4) assessment of dependence. These challenges are discussed, and some suggestions to inform ECIG evaluation using clinical laboratory methods are provided. Conclusions Awareness of challenges and developing, validating, and reporting methods used to address them aids interpretation of results and replication efforts, thus enhancing the rigor of science used to protect public health through appropriate, empirically-based, ECIG regulation. PMID:28819633

Clinical Laboratory Evaluation of Electronic Cigarettes/Electronic Nicotine Delivery Systems: Methodological Challenges.

PubMed

Blank, Melissa D; Breland, Alison B; Cobb, Caroline O; Spindle, Tory; Ramôa, Carolina; Eissenberg, Thomas

2016-10-01

Evaluating electronic cigarettes (ECIGs) in the clinical laboratory is critical to understanding their effects. However, laboratory evaluation of ECIGs can be challenging, as they are a novel, varied, and evolving class of products. The objective of this paper is to describe some methodological challenges to the clinical laboratory evaluation of ECIGs. The authors gathered information about challenges involved in the laboratory evaluation of ECIGs. Challenges were categorized and solutions provided when possible. Methods used to study combustible cigarettes may need to be adapted to account for ECIG novelty and differences within the class. Challenges to ECIG evaluation can include issues related to 1) identification of ECIG devices and liquids, 2) determination of short -term ECIG abstinence, 3) measurement of use behavior, and 4) assessment of dependence. These challenges are discussed, and some suggestions to inform ECIG evaluation using clinical laboratory methods are provided. Awareness of challenges and developing, validating, and reporting methods used to address them aids interpretation of results and replication efforts, thus enhancing the rigor of science used to protect public health through appropriate, empirically-based, ECIG regulation.

Mobile Eye Tracking Methodology in Informal E-Learning in Social Groups in Technology-Enhanced Science Centres

ERIC Educational Resources Information Center

Magnussen, Rikke; Zachariassen, Maria; Kharlamov, Nikita; Larsen, Birger

2017-01-01

This paper presents a methodological discussion of the potential and challenges of involving mobile eye tracking technology in studies of knowledge generation and learning in a science centre context. The methodological exploration is based on eye-tracking studies of audience interaction and knowledge generation in the technology-enhanced health…

Routes of Knowledge: Toward a Methodological Framework for Tracing the Historical Impact of International Organizations

ERIC Educational Resources Information Center

Christensen, Ivan Lind; Ydesen, Christian

2015-01-01

Recent trends in the historiography of international organizations are occupied with tracing their historical impact on national contexts. There is, however, no consensus on how to conduct this type of analysis methodologically. This article examines the methodological challenges arising from this type of research. While a great deal of…

Challenges and unanswered questions for the next decade of circulating tumour cell research in lung cancer

PubMed Central

Mohan, Sumitra; Chemi, Francesca

2017-01-01

Since blood borne circulating tumour cells (CTCs) initially shed from the primary tumour can seed and initiate metastasis at distant sites a better understanding of the biology of CTCs and their dissemination could provide valuable information that could guide therapeutic intervention and real time monitoring of disease progression. Although CTC enumeration has provided a reliable prognostic readout for a number of cancers, including lung cancer, the precise clinical utility of CTCs remains to be established. The rarity of CTCs together with the vanishingly small amounts of nucleic acids present in a single cell as well as cell to cell heterogeneity has stimulated the development of a wide range of powerful cellular and molecular methodologies applied to CTCs. These technical developments are now enabling researchers to focus on understanding the biology of CTCs and their clinical utility as a predictive and pharmacodynamics markers. This review summarises recent advances in the field of CTC research with focus on technical and biological challenges as well the progress made towards clinical utility of characterisation of CTCs with emphasis on studies in lung cancer. PMID:28904889

Polarisation vision: overcoming challenges of working with a property of light we barely see

NASA Astrophysics Data System (ADS)

Foster, James J.; Temple, Shelby E.; How, Martin J.; Daly, Ilse M.; Sharkey, Camilla R.; Wilby, David; Roberts, Nicholas W.

2018-04-01

In recent years, the study of polarisation vision in animals has seen numerous breakthroughs, not just in terms of what is known about the function of this sensory ability, but also in the experimental methods by which polarisation can be controlled, presented and measured. Once thought to be limited to only a few animal species, polarisation sensitivity is now known to be widespread across many taxonomic groups, and advances in experimental techniques are, in part, responsible for these discoveries. Nevertheless, its study remains challenging, perhaps because of our own poor sensitivity to the polarisation of light, but equally as a result of the slow spread of new practices and methodological innovations within the field. In this review, we introduce the most important steps in designing and calibrating polarised stimuli, within the broader context of areas of current research and the applications of new techniques to key questions. Our aim is to provide a constructive guide to help researchers, particularly those with no background in the physics of polarisation, to design robust experiments that are free from confounding factors.

Uncovering the mysteries of inclusion: Empirical and methodological possibilities in participatory evaluation in an international context.

PubMed

Chouinard, Jill Anne; Milley, Peter

2018-04-01

The inclusion of stakeholders in participatory evaluation in highly diverse, culturally complex settings remains a challenge, given issues of inequity, power, voice, capacity and skill. These challenges are well documented, but there is a relative absence of papers devoted to addressing them based on examples and evidence. In this paper, we report our review of 51 empirical studies of participatory evaluations conducted in the international domain, focusing on the methods of inclusion used in the evaluations. Our findings address "the who" (which stakeholders are included and which excluded), "the why" (rationales for participation) and "the how" (by what means and in what manner) of inclusion. We were struck by the scale of some development programs, geographically and in terms of the number of diverse program sponsors and stakeholders, and how this necessitated highly creative, innovative participatory techniques to ensure that anyone (and in some cases everyone) could have a voice in the process, regardless of location, language ability, privilege, power, gender, age or culture. Copyright © 2017 Elsevier Ltd. All rights reserved.

Meta-analysis, complexity, and heterogeneity: a qualitative interview study of researchers' methodological values and practices.

PubMed

Lorenc, Theo; Felix, Lambert; Petticrew, Mark; Melendez-Torres, G J; Thomas, James; Thomas, Sian; O'Mara-Eves, Alison; Richardson, Michelle

2016-11-16

Complex or heterogeneous data pose challenges for systematic review and meta-analysis. In recent years, a number of new methods have been developed to meet these challenges. This qualitative interview study aimed to understand researchers' understanding of complexity and heterogeneity and the factors which may influence the choices researchers make in synthesising complex data. We conducted interviews with a purposive sample of researchers (N = 19) working in systematic review or meta-analysis across a range of disciplines. We analysed data thematically using a framework approach. Participants reported using a broader range of methods and data types in complex reviews than in traditional reviews. A range of techniques are used to explore heterogeneity, but there is some debate about their validity, particularly when applied post hoc. Technical considerations of how to synthesise complex evidence cannot be isolated from questions of the goals and contexts of research. However, decisions about how to analyse data appear to be made in a largely informal way, drawing on tacit expertise, and their relation to these broader questions remains unclear.

Defining operational taxonomic units using DNA barcode data.

PubMed

Blaxter, Mark; Mann, Jenna; Chapman, Tom; Thomas, Fran; Whitton, Claire; Floyd, Robin; Abebe, Eyualem

2005-10-29

The scale of diversity of life on this planet is a significant challenge for any scientific programme hoping to produce a complete catalogue, whatever means is used. For DNA barcoding studies, this difficulty is compounded by the realization that any chosen barcode sequence is not the gene 'for' speciation and that taxa have evolutionary histories. How are we to disentangle the confounding effects of reticulate population genetic processes? Using the DNA barcode data from meiofaunal surveys, here we discuss the benefits of treating the taxa defined by barcodes without reference to their correspondence to 'species', and suggest that using this non-idealist approach facilitates access to taxon groups that are not accessible to other methods of enumeration and classification. Major issues remain, in particular the methodologies for taxon discrimination in DNA barcode data.

Community-level climate change vulnerability research: trends, progress, and future directions

NASA Astrophysics Data System (ADS)

McDowell, Graham; Ford, James; Jones, Julie

2016-03-01

This study systematically identifies, characterizes, and critically evaluates community-level climate change vulnerability assessments published over the last 25 years (n = 274). We find that while the field has advanced considerably in terms of conceptual framing and methodological approaches, key shortcomings remain in how vulnerability is being studied at the community-level. We argue that vulnerability research needs to more critically engage with the following: methods for evaluating future vulnerability, the relevance of vulnerability research for decision-making, interdependencies between social and ecological systems, attention to researcher / subject power dynamics, critical interpretation of key terms, and consideration of the potentially positive opportunities presented by a changing climate. Addressing these research needs is necessary for generating knowledge that supports climate-affected communities in navigating the challenges and opportunities ahead.

Observational methods to assess the effectiveness of screening colonoscopy in reducing right colon cancer mortality risk: SCOLAR.

PubMed

Goodman, Michael; Fletcher, Robert H; Doria-Rose, V Paul; Jensen, Christopher D; Zebrowski, Alexis M; Becerra, Tracy A; Quinn, Virginia P; Zauber, Ann G; Corley, Douglas A; Doubeni, Chyke A

2015-11-01

Screening colonoscopy's effectiveness in reducing risk of death from right colon cancers remains unclear. Methodological challenges of existing observational studies addressing this issue motivated the design of 'Effectiveness of Screening for Colorectal Cancer in Average-Risk Adults (SCOLAR)'. SCOLAR is a nested case-control study based on two large integrated health systems. This affords access to a large, well-defined historical cohort linked to integrated data on cancer outcomes, patient eligibility, test indications and important confounders. We found electronic data adequate for excluding ineligible patients (except family history), but not the detailed information needed for test indication assignment. The lessons of SCOLAR's design and implementation may be useful for future studies seeking to evaluate the effectiveness of screening tests in community settings.

On the experimental approaches for the assessment of the release of engineered nanomaterials from nanocomposites by physical degradation processes

NASA Astrophysics Data System (ADS)

Blázquez, M.; Egizabal, A.; Unzueta, I.

2014-08-01

The LIFE+ Project SIRENA, Simulation of the release of nanomaterials from consumer products for environmental exposure assessment, (LIFE11 ENV/ES/596) has set up a Technological Surveillance System (TSS) to trace technical references at worldwide level related to nanocomposites and the release from nanocomposites. So far a total of seventy three items of different nature (from peer reviewed articles to presentations and contributions to congresses) have been selected and classified as "nanomaterials release simulation technologies". In present document, different approaches for the simulation of different life cycle stages through the physical degradation of polymer nanocomposites at laboratory scale are assessed. In absence of a reference methodology, the comparison of the different protocols used still remains a challenge.

Can Programming Frameworks Bring Smartphones into the Mainstream of Psychological Science?

PubMed

Piwek, Lukasz; Ellis, David A

2016-01-01

Smartphones continue to provide huge potential for psychological science and the advent of novel research frameworks brings new opportunities for researchers who have previously struggled to develop smartphone applications. However, despite this renewed promise, smartphones have failed to become a standard item within psychological research. Here we consider the key issues that continue to limit smartphone adoption within psychological science and how these barriers might be diminishing in light of ResearchKit and other recent methodological developments. We conclude that while these programming frameworks are certainly a step in the right direction it remains challenging to create usable research-orientated applications with current frameworks. Smartphones may only become an asset for psychology and social science as a whole when development software that is both easy to use and secure becomes freely available.

Active Electrodes for Wearable EEG Acquisition: Review and Electronics Design Methodology.

PubMed

Xu, Jiawei; Mitra, Srinjoy; Van Hoof, Chris; Yazicioglu, Refet Firat; Makinwa, Kofi A A

2017-01-01

Active electrodes (AEs), i.e., electrodes with built-in readout circuitry, are increasingly being implemented in wearable healthcare and lifestyle applications due to AEs' robustness to environmental interference. An AE locally amplifies and buffers μV-level EEG signals before driving any cabling. The low output impedance of an AE mitigates cable motion artifacts, thus enabling the use of high-impedance dry electrodes for greater user comfort. However, developing a wearable EEG system, with medical grade signal quality on noise, electrode offset tolerance, common-mode rejection ratio, input impedance, and power dissipation, remains a challenging task. This paper reviews state-of-the-art bio-amplifier architectures and low-power analog circuits design techniques intended for wearable EEG acquisition, with a special focus on an AE system interfaced with dry electrodes.

Methodological Considerations for Research With Black Male Victims of Violent Injury in an Urban Trauma Unit.

PubMed

St Vil, Christopher; Richardson, Joseph; Cooper, Carnell

2018-04-01

There is a body of research over the last three decades that has focused on the etiology of violence among victims of violent injury. This body of literature indicates that Black men are disproportionately represented among victims of violent injury seen in emergency departments and trauma centers across the country. Despite the disproportionate number of low-income young Black men treated for violent injury in urban trauma units and the growing body of literature accompanying it, little is known about the unique methodological challenges violent injury researchers face when conducting research on this vulnerable population in a clinical setting. This article describes the unique and often nuanced methodological difficulties a research team encountered while conducting a longitudinal qualitative study on risk factors for repeat violent injury among low-income young Black male victims of violent injury treated at a Level II trauma center in the Eastern United States. Four methodological challenges are identified: (a) the identification and screening of participants, (b) recruitment and interviewing, (c) understanding hospital culture, policies, and procedures, and (d) retention and attrition of sample. Recommendations to overcome these challenges are offered.

Diagnostic approach in cases with suspected work-related asthma

PubMed Central

2013-01-01

Background Work-related asthma (WRA) is a major cause of respiratory disease in modern societies. The diagnosis and consequently an opportunity for prevention are often missed in practice. Methods Based on recent studies and systematic reviews of the literature methods for detection of WRA and identification of specific causes of allergic WRA are discussed. Results and Conclusions All workers should be asked whether symptoms improve on days away from work or on holidays. Positive answers should lead to further investigation. Spirometry and non-specific bronchial responsiveness should be measured, but carefully performed and validly analysed serial peak expiratory flow or forced expiratory volume in one second (FEV1) measurements are more specific and confirm occupational asthma in about 82% of those still exposed to the causative agent. Skin prick testing or specific immunoglobulin E assays are useful to document allergy to high molecular weight allergens. Specific inhalational challenge tests come closest to a gold standard test, but lack standardisation, availability and sensitivity. Supervised workplace challenges can be used when specific challenges are unavailable or the results non-diagnostic, but methodology lacks standardisation. Finally, if the diagnosis remains unclear a follow-up with serial measurements of FEV1 and non-specific bronchial hyperresponsiveness should detect those likely to develop permanent impairment from their occupational exposures. PMID:23768266

UV Decontamination of MDA Reagents for Single Cell Genomics

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

Lee, Janey; Tighe, Damon; Sczyrba, Alexander

2011-03-18

Single cell genomics, the amplification and sequencing of genomes from single cells, can provide a glimpse into the genetic make-up and thus life style of the vast majority of uncultured microbial cells, making it an immensely powerful and increasingly popular tool. This is accomplished by use of multiple displacement amplification (MDA), which can generate billions of copies of a single bacterial genome producing microgram-range DNA required for shotgun sequencing. Here, we address a key challenge inherent to this approach and propose a solution for the improved recovery of single cell genomes. While DNA-free reagents for the amplification of a singlemore » cell genome are a prerequisite for successful single cell sequencing and analysis, DNA contamination has been detected in various reagents, which poses a considerable challenge. Our study demonstrates the effect of UV irradiation in efficient elimination of exogenous contaminant DNA found in MDA reagents, while maintaining Phi29 activity. Consequently, we also find that increased UV exposure to Phi29 does not adversely affect genome coverage of MDA amplified single cells. While additional challenges in single cell genomics remain to be resolved, the proposed methodology is relatively quick and simple and we believe that its application will be of high value for future single cell sequencing projects.« less

Inclusion and exclusion in nutrigenetics clinical research: ethical and scientific challenges.

PubMed

Hurlimann, T; Stenne, R; Menuz, V; Godard, B

2011-01-01

There are compelling reasons to ensure the participation of ethnic minorities and populations of all ages worldwide in nutrigenetics clinical research. If findings in such research are valid for some individuals, groups, or communities, and not for others, then ethical questions of justice--and not only issues of methodology and external validity--arise. This paper aims to examine inclusion in nutrigenetics clinical research and its scientific and ethical challenges. In total, 173 publications were identified through a systematic review of clinical studies in nutrigenetics published between 1998 and 2007. Data such as participants' demographics as well as eligibility criteria were extracted. There is no consistency in the way participants' origins (ancestry, ethnicity, or race) and ages are described in publications. A vast majority of the studies identified was conducted in North America and Europe and focused on 'white' participants. Our results show that pregnant women (and fetuses), minors, and the elderly (≥ 75 years old) remain underrepresented. Representativeness in nutrigenetics research is a challenging ethical and scientific issue. Yet, if nutrigenetics is to benefit whole populations and be used in public and global health agendas, fair representation as well as clear descriptions of participants in publications are crucial. Copyright © 2012 S. Karger AG, Basel.

The challenge of recreation planning: methodology and factors to consider

Treesearch

Ronald B. Uleck

1971-01-01

The proposed methodology of planning is a description, explanation, and justification of the methods or techniques that a planner should use in preparing outdoor recreation development plans. The sequence of steps required is described

Methodological challenges when doing research that includes ethnic minorities: a scoping review.

PubMed

Morville, Anne-Le; Erlandsson, Lena-Karin

2016-11-01

There are challenging methodological issues in obtaining valid and reliable results on which to base occupational therapy interventions for ethnic minorities. The aim of this scoping review is to describe the methodological problems within occupational therapy research, when ethnic minorities are included. A thorough literature search yielded 21 articles obtained from the scientific databases PubMed, Cinahl, Web of Science and PsychInfo. Analysis followed Arksey and O'Malley's framework for scoping reviews, applying content analysis. The results showed methodological issues concerning the entire research process from defining and recruiting samples, the conceptual understanding, lack of appropriate instruments, data collection using interpreters to analyzing data. In order to avoid excluding the ethnic minorities from adequate occupational therapy research and interventions, development of methods for the entire research process is needed. It is a costly and time-consuming process, but the results will be valid and reliable, and therefore more applicable in clinical practice.

Ethical challenges facing veterinary professionals in Ireland: results from Policy Delphi with vignette methodology

PubMed Central

Magalhães-Sant'Ana, M.; More, S. J.; Morton, D. B.; Hanlon, A.

2016-01-01

Ethics is key to the integrity of the veterinary profession. Despite its importance, there is a lack of applied research on the range of ethical challenges faced by veterinarians. A three round Policy Delphi with vignette methodology was used to record the diversity of views on ethical challenges faced by veterinary professionals in Ireland. Forty experts, comprising veterinary practitioners, inspectors and nurses, accepted to participate. In round 1, twenty vignettes describing a variety of ethically challenging veterinary scenarios were ranked in terms of ethical acceptability, reputational risk and perceived standards of practice. Round 2 aimed at characterising challenges where future policy development or professional guidance was deemed to be needed. In round 3, possible solutions to key challenges were explored. Results suggest that current rules and regulations are insufficient to ensure best veterinary practices and that a collective approach is needed to harness workable solutions for the identified ethical challenges. Challenges pertaining mostly to the food chain seem to require enforcement measures whereas softer measures that promote professional discretion were preferred to address challenges dealing with veterinary clinical services. These findings can support veterinary representative bodies, advisory committees and regulatory authorities in their decision making, policy and regulation. PMID:27613779

Ethical challenges facing veterinary professionals in Ireland: results from Policy Delphi with vignette methodology.

PubMed

Magalhães-Sant'Ana, M; More, S J; Morton, D B; Hanlon, A

2016-10-29

Ethics is key to the integrity of the veterinary profession. Despite its importance, there is a lack of applied research on the range of ethical challenges faced by veterinarians. A three round Policy Delphi with vignette methodology was used to record the diversity of views on ethical challenges faced by veterinary professionals in Ireland. Forty experts, comprising veterinary practitioners, inspectors and nurses, accepted to participate. In round 1, twenty vignettes describing a variety of ethically challenging veterinary scenarios were ranked in terms of ethical acceptability, reputational risk and perceived standards of practice. Round 2 aimed at characterising challenges where future policy development or professional guidance was deemed to be needed. In round 3, possible solutions to key challenges were explored. Results suggest that current rules and regulations are insufficient to ensure best veterinary practices and that a collective approach is needed to harness workable solutions for the identified ethical challenges. Challenges pertaining mostly to the food chain seem to require enforcement measures whereas softer measures that promote professional discretion were preferred to address challenges dealing with veterinary clinical services. These findings can support veterinary representative bodies, advisory committees and regulatory authorities in their decision making, policy and regulation. British Veterinary Association.

“Spatial Energetics”: Integrating Data From GPS, Accelerometry, and GIS to Address Obesity and Inactivity

PubMed Central

James, Peter; Jankowska, Marta; Marx, Christine; Hart, Jaime E.; Berrigan, David; Kerr, Jacqueline; Hurvitz, Philip M.; Hipp, J. Aaron; Laden, Francine

2016-01-01

To address the current obesity and inactivity epidemics, public health researchers have attempted to identify spatial factors that influence physical inactivity and obesity. Technologic and methodologic developments have led to a revolutionary ability to examine dynamic, high-resolution measures of temporally matched location and behavior data through GPS, accelerometry, and GIS. These advances allow the investigation of spatial energetics, high–spatiotemporal resolution data on location and time-matched energetics, to examine how environmental characteristics, space, and time are linked to activity-related health behaviors with far more robust and detailed data than in previous work. Although the transdisciplinary field of spatial energetics demonstrates promise to provide novel insights on how individuals and populations interact with their environment, there remain significant conceptual, technical, analytical, and ethical challenges stemming from the complex data streams that spatial energetics research generates. First, it is essential to better understand what spatial energetics data represent, the relevant spatial context of analysis for these data, and if spatial energetics can establish causality for development of spatially relevant interventions. Second, there are significant technical problems for analysis of voluminous and complex data that may require development of spatially aware scalable computational infrastructures. Third, the field must come to agreement on appropriate statistical methodologies to account for multiple observations per person. Finally, these challenges must be considered within the context of maintaining participant privacy and security. This article describes gaps in current practice and understanding, and suggests solutions to move this promising area of research forward. PMID:27528538

From Biography to Osteobiography: An Example of Anthropological Historical Identification of the Remains of St. Paul.

PubMed

Mihanović, Frane; Jerković, Ivan; Kružić, Ivana; Anđelinović, Šimun; Janković, Stipan; Bašić, Željana

2017-09-01

In the identification process of historical figures, and especially in cases of Saint's bodies or mummified remains, any method that includes physical encroachment or sampling is often not allowed. In these cases, one of the few remaining possibilities is the application of nondestructive radiographical and anthropological methods. However, although there have been a few attempts of such analyses, no systematic standard methodology has been developed until now. In this study, we developed a methodological approach that was used to test the authenticity of the alleged body of Saint Paul the Confessor. Upon imaging the remains on MSCT and post-processing, the images were analyzed by an interdisciplinary team to explore the contents beneath the binding media (e.g., the remains) and to obtain osetobiographical data for comparison with historical biological data. Obtained results: ancestry, sex, age, occupation, and social status were consistent with historical data. Although the methodological approach proved to be appropriate in this case, due to the discrepancy in the amount of data, identity could not be fully confirmed. Nonetheless, the hypothesis that the remains do not belong to St. Paul was rejected, whilst positive identification receives support. Anat Rec, 300:1535-1546, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Assessing species saturation: conceptual and methodological challenges.

PubMed

Olivares, Ingrid; Karger, Dirk N; Kessler, Michael

2018-05-07

Is there a maximum number of species that can coexist? Intuitively, we assume an upper limit to the number of species in a given assemblage, or that a lineage can produce, but defining and testing this limit has proven problematic. Herein, we first outline seven general challenges of studies on species saturation, most of which are independent of the actual method used to assess saturation. Among these are the challenge of defining saturation conceptually and operationally, the importance of setting an appropriate referential system, and the need to discriminate among patterns, processes and mechanisms. Second, we list and discuss the methodological approaches that have been used to study species saturation. These approaches vary in time and spatial scales, and in the variables and assumptions needed to assess saturation. We argue that assessing species saturation is possible, but that many studies conducted to date have conceptual and methodological flaws that prevent us from currently attaining a good idea of the occurrence of species saturation. © 2018 Cambridge Philosophical Society.

The Challenges of Participant Photography: A Critical Reflection on Methodology and Ethics in Two Cultural Contexts.

PubMed

Murray, Linda; Nash, Meredith

2017-05-01

Photovoice and photo-elicitation are two common methods of participant photography used in health research. Although participatory photography has many benefits, this critical reflection provides fellow researchers with insights into the methodological and ethical challenges faced when using such methods. In this article, we critically reflect on two studies that used participatory photography in different cultural contexts. The first study used photo-elicitation to investigate mothers' experiences of infant settling in central Vietnam. The second study used photovoice to explore pregnant embodiment in Australia. Following a discussion of the literature and a detailed overview of the two studies, we examine the methodological challenges in using participant photography before, during and after each study. This is followed by a discussion of ethical concerns that arose in relation to the burden of participation, confidentiality, consent, and the photographing of families and children. To conclude, we highlight implications for using participatory photography in other settings.

Recent advances in computational methodology for simulation of mechanical circulatory assist devices

PubMed Central

Marsden, Alison L.; Bazilevs, Yuri; Long, Christopher C.; Behr, Marek

2014-01-01

Ventricular assist devices (VADs) provide mechanical circulatory support to offload the work of one or both ventricles during heart failure. They are used in the clinical setting as destination therapy, as bridge to transplant, or more recently as bridge to recovery to allow for myocardial remodeling. Recent developments in computational simulation allow for detailed assessment of VAD hemodynamics for device design and optimization for both children and adults. Here, we provide a focused review of the recent literature on finite element methods and optimization for VAD simulations. As VAD designs typically fall into two categories, pulsatile and continuous flow devices, we separately address computational challenges of both types of designs, and the interaction with the circulatory system with three representative case studies. In particular, we focus on recent advancements in finite element methodology that has increased the fidelity of VAD simulations. We outline key challenges, which extend to the incorporation of biological response such as thrombosis and hemolysis, as well as shape optimization methods and challenges in computational methodology. PMID:24449607

Post-Traumatic Stress Symptoms in Post-ICU Family Members: Review and Methodological Challenges.

PubMed

Petrinec, Amy B; Daly, Barbara J

2016-01-01

Family members of intensive care unit (ICU) patients are at risk for symptoms of post-traumatic stress disorder (PTSD) following ICU discharge. The aim of this systematic review is to examine the current literature regarding post-ICU family PTSD symptoms with an emphasis on methodological issues in conducting research on this challenging phenomenon. An extensive review of the literature was performed confining the search to English language studies reporting PTSD symptoms in adult family members of adult ICU patients. Ten studies were identified for review published from 2004 to 2012. Findings demonstrate a significant prevalence of family PTSD symptoms in the months following ICU hospitalization. However, there are several methodological challenges to the interpretation of existing studies and to the conduct of future research including differences in sampling, identification of risk factors and covariates of PTSD, and lack of consensus regarding the most appropriate PTSD symptom measurement tools and timing. © The Author(s) 2014.

Conducting interactive experiments online.

PubMed

Arechar, Antonio A; Gächter, Simon; Molleman, Lucas

2018-01-01

Online labor markets provide new opportunities for behavioral research, but conducting economic experiments online raises important methodological challenges. This particularly holds for interactive designs. In this paper, we provide a methodological discussion of the similarities and differences between interactive experiments conducted in the laboratory and online. To this end, we conduct a repeated public goods experiment with and without punishment using samples from the laboratory and the online platform Amazon Mechanical Turk. We chose to replicate this experiment because it is long and logistically complex. It therefore provides a good case study for discussing the methodological and practical challenges of online interactive experimentation. We find that basic behavioral patterns of cooperation and punishment in the laboratory are replicable online. The most important challenge of online interactive experiments is participant dropout. We discuss measures for reducing dropout and show that, for our case study, dropouts are exogenous to the experiment. We conclude that data quality for interactive experiments via the Internet is adequate and reliable, making online interactive experimentation a potentially valuable complement to laboratory studies.

Methodological Challenges in Researching Threshold Concepts: A Comparative Analysis of Three Projects

ERIC Educational Resources Information Center

Quinlan, K. M.; Male, S.; Baillie, C.; Stamboulis, A.; Fill, J.; Jaffer, Z.

2013-01-01

Threshold concepts were introduced nearly 10 years ago by Ray Land and Jan Meyer. This work has spawned four international conferences and hundreds of papers. Although the idea has clearly gained traction in higher education, this sub-field does not yet have a fully fledged research methodology or a strong critical discourse about methodology.…

Research on Natural Settings: Observing Adolescent Mothers and Infants throughout the First Postpartum Year.

PubMed

Diniz, Eva; Koller, Silvia H

2018-03-01

This manuscript aims to present and discuss challenges regarding naturalistic observation of adolescent mothers and their infants throughout the first postpartum year. Case illustrations were the object to discuss methodological options and issues faced during an observational and longitudinal research. The participants live in vulnerability in a metropolitan area in Southern Brazil. Data collection challenges led to reflections about naturalistic observation and methodological procedures, which were affected by setting characteristics and by the need of adapting to them. Most methodological difficulties were linked to naturalistic observations of mothers and their infants. Personal and contextual aspects of these settings must be taken into account in order to enhance result reliability and the knowledge about cultural idiosyncrasies.

A pilot study to test psychophonetics methodology for self-care and empathy in compassion fatigue, burnout and secondary traumatic stress

PubMed Central

Butler, Nadine

2013-01-01

Abstract Background Home-based care is recognised as being a stressful occupation. Practitioners working with patients experiencing high levels of trauma may be susceptible to compassion fatigue, with the sustained need to remain empathic being a contributing factor. Objectives The aim of this research was to evaluate psychophonetics methodology for self-care and empathy skills as an intervention for compassion fatigue. Objectives were to measure levels of compassion fatigue pre-intervention, then to apply the intervention and retest levels one month and six months post-intervention. Method The research applied a pilot test of a developed intervention as a quasi-experiment. The study sample comprised home-based carers working with HIV-positive patients at a hospice in Grabouw, a settlement in the Western Cape facing socioeconomic challenge. Results The result of the pilot study showed a statistically-significant improvement in secondary traumatic stress, a component of compassion fatigue, measured with the ProQOL v5 instrument post-intervention. Conclusion The results gave adequate indication for the implementation of a larger study in order to apply and test the intervention. The study highlights a dire need for further research in this field.

Potential adjustment methodology for missing data and reporting delay in the HIV Surveillance System, European Union/European Economic Area, 2015.

PubMed

Rosinska, Magdalena; Pantazis, Nikos; Janiec, Janusz; Pharris, Anastasia; Amato-Gauci, Andrew J; Quinten, Chantal; Ecdc Hiv/Aids Surveillance Network

2018-06-01

Accurate case-based surveillance data remain the key data source for estimating HIV burden and monitoring prevention efforts in Europe. We carried out a literature review and exploratory analysis of surveillance data regarding two crucial issues affecting European surveillance for HIV: missing data and reporting delay. Initial screening showed substantial variability of these data issues, both in time and across countries. In terms of missing data, the CD4+ cell count is the most problematic variable because of the high proportion of missing values. In 20 of 31 countries of the European Union/European Economic Area (EU/EEA), CD4+ counts are systematically missing for all or some years. One of the key challenges related to reporting delays is that countries undertake specific one-off actions in effort to capture previously unreported cases, and that these cases are subsequently reported with excessive delays. Slightly different underlying assumptions and effectively different models may be required for individual countries to adjust for missing data and reporting delays. However, using a similar methodology is recommended to foster harmonisation and to improve the accuracy and usability of HIV surveillance data at national and EU/EEA levels.

On uncertainty quantification in hydrogeology and hydrogeophysics

NASA Astrophysics Data System (ADS)

Linde, Niklas; Ginsbourger, David; Irving, James; Nobile, Fabio; Doucet, Arnaud

2017-12-01

Recent advances in sensor technologies, field methodologies, numerical modeling, and inversion approaches have contributed to unprecedented imaging of hydrogeological properties and detailed predictions at multiple temporal and spatial scales. Nevertheless, imaging results and predictions will always remain imprecise, which calls for appropriate uncertainty quantification (UQ). In this paper, we outline selected methodological developments together with pioneering UQ applications in hydrogeology and hydrogeophysics. The applied mathematics and statistics literature is not easy to penetrate and this review aims at helping hydrogeologists and hydrogeophysicists to identify suitable approaches for UQ that can be applied and further developed to their specific needs. To bypass the tremendous computational costs associated with forward UQ based on full-physics simulations, we discuss proxy-modeling strategies and multi-resolution (Multi-level Monte Carlo) methods. We consider Bayesian inversion for non-linear and non-Gaussian state-space problems and discuss how Sequential Monte Carlo may become a practical alternative. We also describe strategies to account for forward modeling errors in Bayesian inversion. Finally, we consider hydrogeophysical inversion, where petrophysical uncertainty is often ignored leading to overconfident parameter estimation. The high parameter and data dimensions encountered in hydrogeological and geophysical problems make UQ a complicated and important challenge that has only been partially addressed to date.

Recent advances in the management of neuropsychiatric symptoms in dementia.

PubMed

Forlenza, Orestes V; Loureiro, Júlia Cunha; Pais, Marcos Vasconcelos; Stella, Florindo

2017-03-01

The present article addresses intriguing questions related to the clinical intervention in distinct neuropsychiatric syndromes of patients with dementia. We reviewed 154 articles published between 2015 and 2016 targeting psychopharmacological and nonpharmacological interventions, and safety-tolerability concerns. We selected 115 articles addressing the purpose of this study. Of these, 33 were chosen because they were dedicated to subtopics: agitation (42), depression (33), apathy (18), sleep disorders/anxiety (8), and psychosis (4). Clinical studies using both pharmacological (70) and nonpharmacological (37) interventions were considered; others were included for theoretical support. Regarding the methodological design, we found double-blind RCTs (17), single-blinded RCTs (4), open-label studies (18), case reports (5), cross-sectional or cohort studies (25), epidemiological papers (2), and expert reviews (44). This observation raises concerns about the overall methodological adequacy of a substantial proportion of studies in this field, which limits the potential of generalization of the findings. Finally, 18 studies were designed to determine safety-tolerability issues of psychotropic medications (6 were discussed). Effective and well tolerated treatment of neuropsychiatric syndromes in dementia remains a critically unsolved challenge. We understand that this is an extremely important area of research, and critically required to guide clinical decisions in geriatric neuropsychiatry.

Engaging men with penile cancer in qualitative research: reflections from an interview-based study.

PubMed

Witty, Karl; Branney, Peter; Bullen, Kate; White, Alan; Evans, Julie; Eardley, Ian

2014-01-01

To explore the challenges of engaging men with penile cancer in qualitative interview research. Qualitative interviewing offers an ideal tool for exploring men's experiences of illness, complementing and providing context to gendered health inequalities identified in epidemiological research on men. But conducting interviews with men can be challenging and embarking on a qualitative interview study with males can feel like a daunting task, given the limited amount of practical, gender-sensitive guidance for researchers. Reflecting on a researcher's experience of conducting qualitative research on men with penile cancer, this paper explores the potential challenges of interviewing this group, but also documents how engagement and data collection were achieved. This is a reflective paper, informed by the experiences of a male researcher (KW) with no nurse training, who conducted 28 interviews with men who had been treated for penile cancer. The researcher's experiences are reported in chronological order, from the methodological challenges of recruitment to those of conducting the interview. The paper offers a resource for the novice researcher, highlighting some advantages and disadvantages of conducting qualitative interview research as a nurse researcher, as well as recommendations on how to overcome challenges. Engaging men with penile cancer in qualitative interview raises practical, methodological, ethical and emotional challenges for the researcher. However, when these challenges are met, men will talk about their health. Methodological procedures must enable an open and ongoing dialogue with clinical gatekeepers and potential participants to promote engagement. Support from colleagues is essential for any interviewer, no matter how experienced the researcher is.

Recommendations for developing and applying genetic tools to assess and manage biological invasions in marine ecosystems

PubMed Central

Darling, John A.; Galil, Bella S.; Carvalho, Gary R.; Rius, Marc; Viard, Frédérique; Piraino, Stefano

2018-01-01

The European Union’s Marine Strategy Framework Directive (MSFD) aims to adopt integrated ecosystem management approaches to achieve or maintain “Good Environmental Status” for marine waters, habitats and resources, including mitigation of the negative effects of non-indigenous species (NIS). The Directive further seeks to promote broadly standardized monitoring efforts and assessment of temporal trends in marine ecosystem condition, incorporating metrics describing the distribution and impacts of NIS. Accomplishing these goals will require application of advanced tools for NIS surveillance and risk assessment, particularly given known challenges associated with surveying and monitoring with traditional methods. In the past decade, a host of methods based on nucleic acids (DNA and RNA) analysis have been developed or advanced that promise to dramatically enhance capacity in assessing and managing NIS. However, ensuring that these rapidly evolving approaches remain accessible and responsive to the needs of resource managers remains a challenge. This paper provides recommendations for future development of these genetic tools for assessment and management of NIS in marine systems, within the context of the explicit requirements of the MSFD. Issues considered include technological innovation, methodological standardization, data sharing and collaboration, and the critical importance of shared foundational resources, particularly integrated taxonomic expertise. Though the recommendations offered here are not exhaustive, they provide a basis for future intentional (and international) collaborative development of a genetic toolkit for NIS research, capable of fulfilling the immediate and long term goals of marine ecosystem and resource conservation. PMID:29681680

Identifying and overcoming implementation challenges: Experience of 59 noninstitutional long-term services and support pilot programs in the Veterans Health Administration

PubMed Central

Sullivan, Jennifer L.; Adjognon, Omonyêlé L.; Engle, Ryann L.; Shin, Marlena H.; Afable, Melissa K.; Rudin, Whitney; White, Bert; Shay, Kenneth; Lukas, Carol VanDeusen

2018-01-01

Background: From 2010 to 2013, the Department of Veterans Affairs (VA) funded a large pilot initiative to implement noninstitutional long-term services and supports (LTSS) programs to support aging Veterans. Our team evaluated implementation of 59 VA noninstitutional LTSS programs. Purpose: The specific objectives of this study are to (a) examine the challenges influencing program implementation comparing active sites that remained open and inactive sites that closed during the funding period and (b) identify ways that active sites overcame the challenges they experienced. Methodology: Key informant semistructured interviews occurred between 2011 and 2013. We conducted 217 telephone interviews over four time points. Content analysis was used to identify emergent themes. The study team met regularly to define each challenge, review all codes, and discuss discrepancies. For each follow-up interview with the sites, the list of established challenges was used as a priori themes. Emergent data were also coded. Results: The challenges affecting implementation included human resources and staffing issues, infrastructure, resources allocation and geography, referrals and marketing, leadership support, and team dynamics and processes. Programs were able to overcome challenges by communicating with team members and other areas in the organization, utilizing information technology solutions, creative use of staff and flexible schedules, and obtaining additional resources. Discussion: This study highlights several common challenges programs can address during the program implementation. The most often mentioned strategy was effective communication. Strategies also targeted several components of the organization including organizational functions and processes (e.g., importance of coordination within a team and across disciplines to provide good care), infrastructure (e.g., information technology and human resources), and program fit with priorities in the organization (e.g., leadership support). Implications: Anticipating potential pitfalls of program implementation for future noninstitutional LTSS programs can improve implementation efficiency and program sustainability. Staff at multiple levels in the organization must fully support noninstitutional LTSS programs to address these challenges. PMID:28125459

Challenges with cost-utility analyses of behavioural interventions among older adults at risk for dementia.

PubMed

Davis, Jennifer C; Bryan, Stirling; Marra, Carlo A; Hsiung, Ging-Yuek R; Liu-Ambrose, Teresa

2015-10-01

Cognitive decline is one of the most prominent healthcare issues of the 21st century. Within the context of combating cognitive decline through behavioural interventions, physical activity is a promising approach. There is a dearth of health economic data in the area of behavioural interventions for dementia prevention. Yet, economic evaluations are essential for providing information to policy makers for resource allocation. It is essential we first address population and intervention-specific methodological challenges prior to building a larger evidence base. We use a cost-utility analysis conducted alongside the exercise for cognition and everyday living (EXCEL) study to illustrate methodological challenges specific to assessing the cost-effectiveness of behavioural interventions aimed at older adults at risk of cognitive decline. A cost-utility analysis conducted concurrently with a 6-month, three-arm randomised controlled trial (ie, the EXCEL study) was used as an example to identify and discuss methodological challenges. Both the aerobic training and resistance training interventions were less costly than twice weekly balance and tone classes. In critically evaluating the economic evaluation of the EXCEL study we identified four category-specific challenges: (1) analysing costs; (2) assessing quality-adjusted life-years; (3) Incomplete data; and (4) 'Intervention' activities of the control group. Resistance training and aerobic training resulted in healthcare cost saving and were equally effective to balance and tone classes after only 6 months of intervention. To ensure this population is treated fairly in terms of claims on resources, we first need to identify areas for methodological improvement. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Selected analytical challenges in the determination of pharmaceuticals in drinking/marine waters and soil/sediment samples.

PubMed

Białk-Bielińska, Anna; Kumirska, Jolanta; Borecka, Marta; Caban, Magda; Paszkiewicz, Monika; Pazdro, Ksenia; Stepnowski, Piotr

2016-03-20

Recent developments and improvements in advanced instruments and analytical methodologies have made the detection of pharmaceuticals at low concentration levels in different environmental matrices possible. As a result of these advances, over the last 15 years residues of these compounds and their metabolites have been detected in different environmental compartments and pharmaceuticals have now become recognized as so-called 'emerging' contaminants. To date, a lot of papers have been published presenting the development of analytical methodologies for the determination of pharmaceuticals in aqueous and solid environmental samples. Many papers have also been published on the application of the new methodologies, mainly to the assessment of the environmental fate of pharmaceuticals. Although impressive improvements have undoubtedly been made, in order to fully understand the behavior of these chemicals in the environment, there are still numerous methodological challenges to be overcome. The aim of this paper therefore, is to present a review of selected recent improvements and challenges in the determination of pharmaceuticals in environmental samples. Special attention has been paid to the strategies used and the current challenges (also in terms of Green Analytical Chemistry) that exist in the analysis of these chemicals in soils, marine environments and drinking waters. There is a particular focus on the applicability of modern sorbents such as carbon nanotubes (CNTs) in sample preparation techniques, to overcome some of the problems that exist in the analysis of pharmaceuticals in different environmental samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Assessing chronic fish health: An application to a case of an acute exposure to chemically treated crude oil.

PubMed

Mauduit, F; Domenici, P; Farrell, A P; Lacroix, C; Le Floch, S; Lemaire, P; Nicolas-Kopec, A; Whittington, M; Zambonino-Infante, J L; Claireaux, G

2016-09-01

Human alteration of marine ecosystems is substantial and growing. Yet, no adequate methodology exists that provides reliable predictions of how environmental degradation will affect these ecosystems at a relevant level of biological organization. The primary objective of this study was to develop a methodology to evaluate a fish's capacity to face a well-established environmental challenge, an exposure to chemically dispersed oil, and characterize the long-term consequences. Therefore, we applied high-throughput, non-lethal challenge tests to assess hypoxia tolerance, temperature susceptibility and maximal swimming speed as proxies for a fish's functional integrity. These whole animal challenge tests were implemented before (1 month) and after (1 month) juvenile European sea bass (Dicentrarchus labrax) had been acutely exposed (48h) to a mixture containing 0.08gL(-1) of weathered Arabian light crude oil plus 4% dispersant (Corexit© EC9500A), a realistic exposure concentration during an oil spill. In addition, experimental populations were then transferred into semi-natural tidal mesocosm ponds and correlates of Darwinian fitness (growth and survival) were monitored over a period of 4 months. Our results revealed that fish acutely exposed to chemically dispersed oil remained impaired in terms of their hypoxia tolerance and swimming performance, but not in temperature susceptibility for 1 month post-exposure. Nevertheless, these functional impairments had no subsequent ecological consequences under mildly selective environmental conditions since growth and survival were not impacted during the mesocosm pond study. Furthermore, the earlier effects on fish performance were presumably temporary because re-testing the fish 10 months post-exposure revealed no significant residual effects on hypoxia tolerance, temperature susceptibility and maximal swimming speed. We propose that the functional proxies and correlates of Darwinian fitness used here provide a useful assessment tool for fish health in the marine environment. Copyright © 2016 Elsevier B.V. All rights reserved.

Voluntary medical male circumcision: a qualitative study exploring the challenges of costing demand creation in eastern and southern Africa.

PubMed

Bertrand, Jane T; Njeuhmeli, Emmanuel; Forsythe, Steven; Mattison, Sarah K; Mahler, Hally; Hankins, Catherine A

2011-01-01

This paper proposes an approach to estimating the costs of demand creation for voluntary medical male circumcision (VMMC) scale-up in 13 countries of eastern and southern Africa. It addresses two key questions: (1) what are the elements of a standardized package for demand creation? And (2) what challenges exist and must be taken into account in estimating the costs of demand creation? We conducted a key informant study on VMMC demand creation using purposive sampling to recruit seven people who provide technical assistance to government programs and manage budgets for VMMC demand creation. Key informants provided their views on the important elements of VMMC demand creation and the most effective funding allocations across different types of communication approaches (e.g., mass media, small media, outreach/mobilization). The key finding was the wide range of views, suggesting that a standard package of core demand creation elements would not be universally applicable. This underscored the importance of tailoring demand creation strategies and estimates to specific country contexts before estimating costs. The key informant interviews, supplemented by the researchers' field experience, identified these issues to be addressed in future costing exercises: variations in the cost of VMMC demand creation activities by country and program, decisions about the quality and comprehensiveness of programming, and lack of data on critical elements needed to "trigger the decision" among eligible men. Based on this study's findings, we propose a seven-step methodological approach to estimate the cost of VMMC scale-up in a priority country, based on our key assumptions. However, further work is needed to better understand core components of a demand creation package and how to cost them. Notwithstanding the methodological challenges, estimating the cost of demand creation remains an essential element in deriving estimates of the total costs for VMMC scale-up in eastern and southern Africa.

Voluntary Medical Male Circumcision: A Qualitative Study Exploring the Challenges of Costing Demand Creation in Eastern and Southern Africa

PubMed Central

Bertrand, Jane T.; Njeuhmeli, Emmanuel; Forsythe, Steven; Mattison, Sarah K.; Mahler, Hally; Hankins, Catherine A.

2011-01-01

Background This paper proposes an approach to estimating the costs of demand creation for voluntary medical male circumcision (VMMC) scale-up in 13 countries of eastern and southern Africa. It addresses two key questions: (1) what are the elements of a standardized package for demand creation? And (2) what challenges exist and must be taken into account in estimating the costs of demand creation? Methods and Findings We conducted a key informant study on VMMC demand creation using purposive sampling to recruit seven people who provide technical assistance to government programs and manage budgets for VMMC demand creation. Key informants provided their views on the important elements of VMMC demand creation and the most effective funding allocations across different types of communication approaches (e.g., mass media, small media, outreach/mobilization). The key finding was the wide range of views, suggesting that a standard package of core demand creation elements would not be universally applicable. This underscored the importance of tailoring demand creation strategies and estimates to specific country contexts before estimating costs. The key informant interviews, supplemented by the researchers' field experience, identified these issues to be addressed in future costing exercises: variations in the cost of VMMC demand creation activities by country and program, decisions about the quality and comprehensiveness of programming, and lack of data on critical elements needed to “trigger the decision” among eligible men. Conclusions Based on this study's findings, we propose a seven-step methodological approach to estimate the cost of VMMC scale-up in a priority country, based on our key assumptions. However, further work is needed to better understand core components of a demand creation package and how to cost them. Notwithstanding the methodological challenges, estimating the cost of demand creation remains an essential element in deriving estimates of the total costs for VMMC scale-up in eastern and southern Africa. PMID:22140450

Developing a Robust Strategy for Implementing a Water Resources Master Plan in Lima, Peru

NASA Astrophysics Data System (ADS)

Kalra, N.; Groves, D.; Bonzanigo, L.; Molina-Perez, E.

2015-12-01

Lima, the capital of Peru, faces significant water stress. It is the fifth largest metropolitan area in Latin America, and the second largest desert city in the world. The city has developed a Master Plan of major investment projects to improve water reliability until 2040. Yet key questions remain. Is the Master Plan sufficient for ensuring reliability in the face of deeply uncertain future climate change and demand? How do uncertain budget and project feasibility conditions shape Lima's options? How should the investments in the plan be prioritized, and can some be delayed? Lima is not alone in facing these planning challenges. Governments invest billions of dollars annually in long-term projects. Yet deep uncertainties pose formidable challenges to making near-term decisions that make long-term sense. The World Bank has spearheaded a community of practice on methods for Decision Making Under Deep Uncertainty (DMU). This pilot project in Peru is the first in-depth application of DMU techniques to water supply planning in a developing country. It builds on prior analysis done in New York, California, and for the Colorado River, yet shows how these methods can be applied in regions which do not have as advanced data or tools available. The project combines three methods in particular -- Robust Decision Making, Decision Scaling, and Adaptive Pathways -- to help Lima implement its Master Plan in a way that is robust, no-regret, and adaptive. It was done in close partnership with SEDAPAL, the water utility company in Lima, and in coordination with other national WRM and meteorological agencies. This talk will: Present the planning challenges Lima and other cities face, including climate change Describe DMU methodologies and how they were applied in collaboration with SEDAPAL Summarize recommendations for achieving long-term water reliability in Lima Suggest how these methodologies can benefit other investment projects in developing countries.

Voice quality outcomes of idiopathic Parkinson's disease medical treatment: A systematic review.

PubMed

Lechien, J R; Blecic, S; Huet, K; Delvaux, V; Piccaluga, M; Roland, V; Harmegnies, B; Saussez, S

2018-06-01

To investigate voice quality (VQ) impairments in idiopathic Parkinson's disease (IPD) and to explore the impact of medical treatments and L-Dopa challenge testing on voice. Relevant studies published between January 1980 and June 2017 describing VQ evaluations in IPD were retrieved using PubMed, Scopus, Biological Abstracts, BioMed Central and Cochrane databases. Issues of clinical relevance, including IPD treatment efficiency and voice quality outcomes, were evaluated for each study. The grade of recommendation for each publication was determined according to the Oxford Centre for Evidence-Based Medicine evidence levels. The database research yielded 106 relevant publications, of which 33 studies met the inclusion criteria, for a total of 964 patients with IPD. Data were extracted by 3 independent physicians who identified 21, 11 and 1 trials with IIIb, IIb and IIa evidence levels, respectively. The main VQ assessment tools used were acoustic testing (N = 27), aerodynamic testing (N = 10), subjective measurements (N = 8) and videolaryngostroboscopy (N = 3). The majority of trials (N = 32/33) identified subjective or objective VQ improvements after medical treatment (N = 10) or better VQ evaluations in healthy subjects compared to patients with IPD (N = 22). Especially, our analysis supports that VQ overall improves during the L-Dopa challenge testing, making the VQ evaluation an additional tool for the IPD diagnosis. The methodology used to assess subjective and objective VQ substantially varied from 1 study to another. All of the included studies took into consideration the patient's clinical profile in the VQ analysis. The majority of studies supported that VQ assessments remain useful as outcome measures of the effectiveness of medical treatment and could be helpful for the IPD diagnosis based on L-Dopa challenge testing. Further controlled studies using standardised and transparent methodology for measuring acoustic parameters are necessary to confirm the place of each tool in both IPD diagnosis and treatment evaluation. © 2018 John Wiley & Sons Ltd.

Integrated Testing Strategy (ITS) - Opportunities to better use existing data and guide future testing in toxicology.

PubMed

Jaworska, Joanna; Hoffmann, Sebastian

2010-01-01

The topic of Integrated Testing Strategies (ITS) has attracted considerable attention, and not only because it is supposed to be a central element of REACH, the ambitious European chemical regulation effort. Although what ITSs are supposed to do seems unambiguous, i.e. speeding up hazard and risk assessment while reducing testing costs, not much has been said, except basic conceptual proposals, about the methodologies that would allow execution of these concepts. Although a pressing concern, the topic of ITS has drawn mostly general reviews, broad concepts, and the expression of a clear need for more research on ITS. Published research in the field remains scarce. Solutions for ITS design emerge slowly, most likely due to the methodological challenges of the task, and perhaps also to it its complexity and the need for multidisciplinary collaboration. Along with the challenge, ITS offer a unique opportunity to contribute to the Toxicology of the 21st century by providing frameworks and tools to actually implement 21st century toxicology data in the chemical management and decision making processes. Further, ITS have the potential to significantly contribute to a modernization of the science of risk assessment. Therefore, to advance ITS research we propose a methodical approach to their design and will discuss currently available approaches as well as challenges to overcome. To this end, we define a framework for ITS that will inform toxicological decisions in a systematic, transparent, and consistent way. We review conceptual requirements for ITS developed earlier and present a roadmap to an operational framework that should be probabilistic, hypothesis-driven, and adaptive. Furthermore, we define properties an ITS should have in order to meet the identified requirements and differentiate them from evidence synthesis. Making use of an ITS for skin sensitization, we demonstrate how the proposed ITS concepts can be implemented.

Learning through Work: Emerging Perspectives and New Challenges

ERIC Educational Resources Information Center

Billett, Stephen; Choy, Sarojni

2013-01-01

Purpose: This paper aims to consider and appraise current developments and emerging perspectives on learning in the circumstances of work, to propose how some of the challenges for securing effective workplace learning may be redressed. Design/methodology/approach: First, new challenges and perspectives on learning in the circumstances of work are…

Applications of landscape genetics in conservation biology: concepts and challenges

Treesearch

Gernot Segelbacher; Samuel A. Cushman; Bryan K. Epperson; Marie-Josee Fortin; Olivier Francois; Olivier J. Hardy; Rolf Holderegger; Stephanie Manel

2010-01-01

Landscape genetics plays an increasingly important role in the management and conservation of species. Here, we highlight some of the opportunities and challenges in using landscape genetic approaches in conservation biology. We first discuss challenges related to sampling design and introduce several recent methodological developments in landscape genetics (analyses...

Analysis of Challenges for Management Education in India Using Total Interpretive Structural Modelling

ERIC Educational Resources Information Center

Mahajan, Ritika; Agrawal, Rajat; Sharma, Vinay; Nangia, Vinay

2016-01-01

Purpose: The purpose of this paper is to identify challenges for management education in India and explain their nature, significance and interrelations using total interpretive structural modelling (TISM), an innovative version of Warfield's interpretive structural modelling (ISM). Design/methodology/approach: The challenges have been drawn from…

Challenge-Based Instruction: The VaNTH Biomechanics Learning Modules

ERIC Educational Resources Information Center

Barr, Ronald E.; Pandy, Marcus G.; Petrosino, Anthony J.; Roselli, Robert J.; Brophy, Sean; Freeman, Robert A.

2007-01-01

This paper presents the methodology and results of teaching an entire engineering course using challenge-based instruction. The challenges consisted of eight biomechanics multimedia learning modules developed by the authors as part of a broader NSF educational coalition. The biomechanics modules were presented in an undergraduate mechanical…

Farms and Learning Partnerships in Farming Systems Projects: A Response to the Challenges of Complexity in Agricultural Innovation

ERIC Educational Resources Information Center

Crawford, Anne; Nettle, Ruth; Paine, Mark; Kabore, Carolyn

2007-01-01

Managing the competing interests of productivity growth, environmental concerns, landscape change and societal expectations presents challenges for agricultural industries. Innovation projects supporting knowledge development to address these challenges often involve partnerships with commercial farms, a methodology which promises much but has…

Nucleic acids-based tools for ballast water surveillance, monitoring, and research

NASA Astrophysics Data System (ADS)

Darling, John A.; Frederick, Raymond M.

2018-03-01

Understanding the risks of biological invasion posed by ballast water-whether in the context of compliance testing, routine monitoring, or basic research-is fundamentally an exercise in biodiversity assessment, and as such should take advantage of the best tools available for tackling that problem. The past several decades have seen growing application of genetic methods for the study of biodiversity, driven in large part by dramatic technological advances in nucleic acids analysis. Monitoring approaches based on such methods have the potential to increase dramatically sampling throughput for biodiversity assessments, and to improve on the sensitivity, specificity, and taxonomic accuracy of traditional approaches. The application of targeted detection tools (largely focused on PCR but increasingly incorporating novel probe-based methodologies) has led to a paradigm shift in rare species monitoring, and such tools have already been applied for early detection in the context of ballast water surveillance. Rapid improvements in community profiling approaches based on high throughput sequencing (HTS) could similarly impact broader efforts to catalogue biodiversity present in ballast tanks, and could provide novel opportunities to better understand the risks of biotic exchange posed by ballast water transport-and the effectiveness of attempts to mitigate those risks. These various approaches still face considerable challenges to effective implementation, depending on particular management or research needs. Compliance testing, for instance, remains dependent on accurate quantification of viable target organisms; while tools based on RNA detection show promise in this context, the demands of such testing require considerable additional investment in methods development. In general surveillance and research contexts, both targeted and community-based approaches are still limited by various factors: quantification remains a challenge (especially for taxa in larger size classes), gaps in nucleic acids reference databases are still considerable, uncertainties in taxonomic assignment methods persist, and many applications have not yet matured sufficiently to offer standardized methods capable of meeting rigorous quality assurance standards. Nevertheless, the potential value of these tools, their growing utilization in biodiversity monitoring, and the rapid methodological advances over the past decade all suggest that they should be seriously considered for inclusion in the ballast water surveillance toolkit.

Two-thirds of methodological research remained unpublished after presentation at Cochrane Colloquia: an empirical analysis.

PubMed

Chapman, Sarah; Eisinga, Anne; Hopewell, Sally; Clarke, Mike

2012-05-01

To determine the extent to which abstracts of methodology research, initially presented at annual meetings of The Cochrane Collaboration, have been published as full reports and over what period of time. A secondary aim was to explore whether full publication varied in different methodological subject areas. The Cochrane Methodology Register (CMR) was searched for all abstracts reporting methodology research, presented at the 11 Cochrane Colloquia from 1997 to 2007. EMBASE, PubMed, and CMR were searched for full publications of the same research. We identified 908 eligible conference abstracts and found full publications for 312 (34.4%) of these, almost half of which (47.1%) had appeared by the end of the first year after the relevant Colloquium. The proportion of abstracts that had not been published by 3 years was 69.7%, falling to 66.2% at 5 years. Publication varied considerably between different methodological areas. Approximately two-thirds of methodological research studies presented at Cochrane Colloquia remain unpublished as full papers at least 5 years later. This highlights the importance of searching conference abstracts if one wishes to find as comprehensive and complete a sample of methodological research as possible. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.

Cochrane Rehabilitation Methodology Committee: an international survey of priorities for future work.

PubMed

Levack, William M; Meyer, Thorsten; Negrini, Stefano; Malmivaara, Antti

2017-10-01

Cochrane Rehabilitation aims to improve the application of evidence-based practice in rehabilitation. It also aims to support Cochrane in the production of reliable, clinically meaningful syntheses of evidence related to the practice of rehabilitation, while accommodating the many methodological challenges facing the field. To this end, Cochrane Rehabilitation established a Methodology Committee to examine, explore and find solutions for the methodological challenges related to evidence synthesis and knowledge translation in rehabilitation. We conducted an international online survey via Cochrane Rehabilitation networks to canvass opinions regarding the future work priorities for this committee and to seek information on people's current capabilities to assist with this work. The survey findings indicated strongest interest in work on how reviewers have interpreted and applied Cochrane methods in reviews on rehabilitation topics in the past, and on gathering a collection of existing publications on review methods for undertaking systematic reviews relevant to rehabilitation. Many people are already interested in contributing to the work of the Methodology Committee and there is a large amount of expertise for this work in the extended Cochrane Rehabilitation network already.

Satellite Tasking via a Tablet Computer

DTIC Science & Technology

2015-09-01

connectivity have helped to overcome the challenges of information delivery , but there remains the challenge of real-time information. This thesis...have helped to overcome the challenges of information delivery , but there remains the challenge of real-time information. This thesis examines the...76  3.  Integration with Existing Programs for Access and Dissemination of Imagery

Feminist methodologies and engineering education research

NASA Astrophysics Data System (ADS)

Beddoes, Kacey

2013-03-01

This paper introduces feminist methodologies in the context of engineering education research. It builds upon other recent methodology articles in engineering education journals and presents feminist research methodologies as a concrete engineering education setting in which to explore the connections between epistemology, methodology and theory. The paper begins with a literature review that covers a broad range of topics featured in the literature on feminist methodologies. Next, data from interviews with engineering educators and researchers who have engaged with feminist methodologies are presented. The ways in which feminist methodologies shape their research topics, questions, frameworks of analysis, methods, practices and reporting are each discussed. The challenges and barriers they have faced are then discussed. Finally, the benefits of further and broader engagement with feminist methodologies within the engineering education community are identified.

Uncertainty Quantification in Remaining Useful Life of Aerospace Components using State Space Models and Inverse FORM

NASA Technical Reports Server (NTRS)

Sankararaman, Shankar; Goebel, Kai

2013-01-01

This paper investigates the use of the inverse first-order reliability method (inverse- FORM) to quantify the uncertainty in the remaining useful life (RUL) of aerospace components. The prediction of remaining useful life is an integral part of system health prognosis, and directly helps in online health monitoring and decision-making. However, the prediction of remaining useful life is affected by several sources of uncertainty, and therefore it is necessary to quantify the uncertainty in the remaining useful life prediction. While system parameter uncertainty and physical variability can be easily included in inverse-FORM, this paper extends the methodology to include: (1) future loading uncertainty, (2) process noise; and (3) uncertainty in the state estimate. The inverse-FORM method has been used in this paper to (1) quickly obtain probability bounds on the remaining useful life prediction; and (2) calculate the entire probability distribution of remaining useful life prediction, and the results are verified against Monte Carlo sampling. The proposed methodology is illustrated using a numerical example.

Advancing scoping study methodology: a web-based survey and consultation of perceptions on terminology, definition and methodological steps.

PubMed

O'Brien, Kelly K; Colquhoun, Heather; Levac, Danielle; Baxter, Larry; Tricco, Andrea C; Straus, Sharon; Wickerson, Lisa; Nayar, Ayesha; Moher, David; O'Malley, Lisa

2016-07-26

Scoping studies (or reviews) are a method used to comprehensively map evidence across a range of study designs in an area, with the aim of informing future research practice, programs and policy. However, no universal agreement exists on terminology, definition or methodological steps. Our aim was to understand the experiences of, and considerations for conducting scoping studies from the perspective of academic and community partners. Primary objectives were to 1) describe experiences conducting scoping studies including strengths and challenges; and 2) describe perspectives on terminology, definition, and methodological steps. We conducted a cross-sectional web-based survey with clinicians, educators, researchers, knowledge users, representatives from community-based organizations, graduate students, and policy stakeholders with experience and/or interest in conducting scoping studies to gain an understanding of experiences and perspectives on the conduct and reporting of scoping studies. We administered an electronic self-reported questionnaire comprised of 22 items related to experiences with scoping studies, strengths and challenges, opinions on terminology, and methodological steps. We analyzed questionnaire data using descriptive statistics and content analytical techniques. Survey results were discussed during a multi-stakeholder consultation to identify key considerations in the conduct and reporting of scoping studies. Of the 83 invitations, 54 individuals (65 %) completed the scoping questionnaire, and 48 (58 %) attended the scoping study meeting from Canada, the United Kingdom and United States. Many scoping study strengths were dually identified as challenges including breadth of scope, and iterative process. No consensus on terminology emerged, however key defining features that comprised a working definition of scoping studies included the exploratory mapping of literature in a field; iterative process, inclusion of grey literature; no quality assessment of included studies, and an optional consultation phase. We offer considerations for the conduct and reporting of scoping studies for researchers, clinicians and knowledge users engaging in this methodology. Lack of consensus on scoping terminology, definition and methodological steps persists. Reasons for this may be attributed to diversity of disciplines adopting this methodology for differing purposes. Further work is needed to establish guidelines on the reporting and methodological quality assessment of scoping studies.

Evaluation of AMSTAR to assess the methodological quality of systematic reviews in overviews of reviews of healthcare interventions.

PubMed

Pollock, Michelle; Fernandes, Ricardo M; Hartling, Lisa

2017-03-23

Overviews of reviews (overviews) compile information from multiple systematic reviews (SRs) to provide a single synthesis of relevant evidence for decision-making. It is recommended that authors assess and report the methodological quality of SRs in overviews-for example, using A MeaSurement Tool to Assess systematic Reviews (AMSTAR). Currently, there is variation in whether and how overview authors assess and report SR quality, and limited guidance is available. Our objectives were to: examine methodological considerations involved in using AMSTAR to assess the quality of Cochrane and non-Cochrane SRs in overviews of healthcare interventions; identify challenges (and develop potential decision rules) when using AMSTAR in overviews; and examine the potential impact of considering methodological quality when making inclusion decisions in overviews. We selected seven overviews of healthcare interventions and included all SRs meeting each overview's inclusion criteria. For each SR, two reviewers independently conducted AMSTAR assessments with consensus and discussed challenges encountered. We also examined the correlation between AMSTAR assessments and SR results/conclusions. Ninety-five SRs were included (30 Cochrane, 65 non-Cochrane). Mean AMSTAR assessments (9.6/11 vs. 5.5/11; p < 0.001) and inter-rater reliability (AC1 statistic: 0.84 vs. 0.69; "almost perfect" vs. "substantial" using the Landis & Koch criteria) were higher for Cochrane compared to non-Cochrane SRs. Four challenges were identified when applying AMSTAR in overviews: the scope of the SRs and overviews often differed; SRs examining similar topics sometimes made different methodological decisions; reporting of non-Cochrane SRs was sometimes poor; and some non-Cochrane SRs included other SRs as well as primary studies. Decision rules were developed to address each challenge. We found no evidence that AMSTAR assessments were correlated with SR results/conclusions. Results indicate that the AMSTAR tool can be used successfully in overviews that include Cochrane and non-Cochrane SRs, though decision rules may be useful to circumvent common challenges. Findings support existing recommendations that quality assessments of SRs in overviews be conducted independently, in duplicate, with a process for consensus. Results also suggest that using methodological quality to guide inclusion decisions (e.g., to exclude poorly conducted and reported SRs) may not introduce bias into the overview process.

On the Reconstruction of Palaeo-Ice Sheets: Recent Advances and Future Challenges

NASA Technical Reports Server (NTRS)

Stokes, Chris R.; Tarasov, Lev; Blomdin, Robin; Cronin, Thomas M.; Fisher, Timothy G.; Gyllencreutz, Richard; Hattestrand, Clas; Heyman, Jacob; Hindmarsh, Richard C. A.; Hughes, Anna L. C.;

On the reconstruction of palaeo-ice sheets: Recent advances and future challenges

USGS Publications Warehouse

Stokes, Chris R.; Tarasov, Lev; Blomdin, Robin; Cronin, Thomas M.; Fisher, Timothy G.; Gyllencreutz, Richard; Hattestrand, Clas; Heyman, Jakob; Hindmarsh, Richard C. A.; Hughes, Anna L. C.; Jakobsson, Martin; Kirchner, Nina; Livingstone, Stephen J.; Margold, Martin; Murton, Julian B.; Noormets, Riko; Peltier, W. Richard; Peteet, Dorothy M.; Piper, David J. W.; Preusser, Frank; Renssen, Hans; Roberts, David H.; Roche, Didier M.; Saint-Ange, Francky; Stroeven, Arjen P.; Teller, James T.

2015-01-01

Reconstructing the growth and decay of palaeo-ice sheets is critical to understanding mechanisms of global climate change and associated sea-level fluctuations in the past, present and future. The significance of palaeo-ice sheets is further underlined by the broad range of disciplines concerned with reconstructing their behaviour, many of which have undergone a rapid expansion since the 1980s. In particular, there has been a major increase in the size and qualitative diversity of empirical data used to reconstruct and date ice sheets, and major improvements in our ability to simulate their dynamics in numerical ice sheet models. These developments have made it increasingly necessary to forge interdisciplinary links between sub-disciplines and to link numerical modelling with observations and dating of proxy records. The aim of this paper is to evaluate recent developments in the methods used to reconstruct ice sheets and outline some key challenges that remain, with an emphasis on how future work might integrate terrestrial and marine evidence together with numerical modelling. Our focus is on pan-ice sheet reconstructions of the last deglaciation, but regional case studies are used to illustrate methodological achievements, challenges and opportunities. Whilst various disciplines have made important progress in our understanding of ice-sheet dynamics, it is clear that data-model integration remains under-used, and that uncertainties remain poorly quantified in both empirically-based and numerical ice-sheet reconstructions. The representation of past climate will continue to be the largest source of uncertainty for numerical modelling. As such, palaeo-observations are critical to constrain and validate modelling. State-of-the-art numerical models will continue to improve both in model resolution and in the breadth of inclusion of relevant processes, thereby enabling more accurate and more direct comparison with the increasing range of palaeo-observations. Thus, the capability is developing to use all relevant palaeo-records to more strongly constrain deglacial (and to a lesser extent pre-LGM) ice sheet evolution. In working towards that goal, the accurate representation of uncertainties is required for both constraint data and model outputs. Close cooperation between modelling and data-gathering communities is essential to ensure this capability is realised and continues to progress.

On the intersection of phonetic detail and the organization of interaction: clinical connections.

PubMed

Walker, Gareth; Local, John

2013-01-01

The analysis of language use in real-world contexts poses particular methodological challenges. We codify responses to these challenges as a series of methodological imperatives. To demonstrate the relevance of these imperatives to clinical investigation, we present analyses of single episodes of interaction where one participant has a speech and/or language impairment: atypical prosody, echolalia and dysarthria. We demonstrate there is considerable heuristic and analytic value in taking this approach to analysing the organization of interaction involving individuals with a speech and/or language impairment.

Survey of systematic review authors in dentistry: challenges in methodology and reporting.

PubMed

Major, Michael P; Warren, Sharon; Flores-Mir, Carlos

2009-04-01

The study reported in this article had three objectives: 1) identify the challenges faced by authors of dental systematic reviews (SR) during the process of literature search and selection; 2) determine whether dental SR authors' responses to survey questions about their study methodology were consistent with the reported published methodology; and 3) assess whether dental SR authors' evidence-based publication experience was associated with reported methodology. Seventy-eight authors (53 percent) of dental SRs out of 147 potential authors published from 2000 to 2006 responded to an online survey. According to the respondents, the most challenging aspects of literature search and selection were the initial design and performing extended literature searches. Agreement between the protocol identified by SR authors on the survey and the actual protocol described in their publications was fair to moderate. There were virtually no correlations between authors' publication experience, systematic review literature search, and selection thoroughness except for the number of past SRs published, and no differences in thoroughness between SRs written by clinicians (dental practitioners in the community) and dental school faculty members. Dental SR authors do not appear to fully appreciate the importance of extensive literature searches as central to the validity of their systematic review methods and potential findings.

The inverse problem in electroencephalography using the bidomain model of electrical activity.

PubMed

Lopez Rincon, Alejandro; Shimoda, Shingo

2016-12-01

Acquiring information about the distribution of electrical sources in the brain from electroencephalography (EEG) data remains a significant challenge. An accurate solution would provide an understanding of the inner mechanisms of the electrical activity in the brain and information about damaged tissue. In this paper, we present a methodology for reconstructing brain electrical activity from EEG data by using the bidomain formulation. The bidomain model considers continuous active neural tissue coupled with a nonlinear cell model. Using this technique, we aim to find the brain sources that give rise to the scalp potential recorded by EEG measurements taking into account a non-static reconstruction. We simulate electrical sources in the brain volume and compare the reconstruction to the minimum norm estimates (MNEs) and low resolution electrical tomography (LORETA) results. Then, with the EEG dataset from the EEG Motor Movement/Imagery Database of the Physiobank, we identify the reaction to visual stimuli by calculating the time between stimulus presentation and the spike in electrical activity. Finally, we compare the activation in the brain with the registered activation using the LinkRbrain platform. Our methodology shows an improved reconstruction of the electrical activity and source localization in comparison with MNE and LORETA. For the Motor Movement/Imagery Database, the reconstruction is consistent with the expected position and time delay generated by the stimuli. Thus, this methodology is a suitable option for continuously reconstructing brain potentials. Copyright © 2016 The Author(s). Published by Elsevier B.V. All rights reserved.

Changing panorama for surveillance of device-associated healthcare infections: Challenges faced in implementation of current guidelines.

PubMed

Gupta, Renu; Sharma, Sangeeta; Saxena, Sonal

2018-01-01

Healthcare-associated infections (HAI) are preventable in up to 30% of patients with evidence-based infection prevention and control (IPC) activities. IPC activities require effective surveillance to generate data for the HAI rates, defining priority areas, identifying processes amenable for improvement and institute interventions to improve patient's safety. However, uniform, accurate and standardised surveillance methodology using objective definitions can only generate meaningful data for effective execution of IPC activities. The highly exhaustive, complex and ever-evolving infection surveillance methodology pose a challenge for effective data capture, analysis and interpretation by ground level personnel. The present review addresses the gaps in knowledge and day-to-day challenges in surveillance faced by infection control team for effective implementation of IPC activities.

Challenges in Rotorcraft Acoustic Flight Prediction and Validation

NASA Technical Reports Server (NTRS)

Boyd, D. Douglas, Jr.

2003-01-01

Challenges associated with rotorcraft acoustic flight prediction and validation are examined. First, an outline of a state-of-the-art rotorcraft aeroacoustic prediction methodology is presented. Components including rotorcraft aeromechanics, high resolution reconstruction, and rotorcraft acoustic prediction arc discussed. Next, to illustrate challenges and issues involved, a case study is presented in which an analysis of flight data from a specific XV-15 tiltrotor acoustic flight test is discussed in detail. Issues related to validation of methodologies using flight test data are discussed. Primary flight parameters such as velocity, altitude, and attitude are discussed and compared for repeated flight conditions. Other measured steady state flight conditions are examined for consistency and steadiness. A representative example prediction is presented and suggestions are made for future research.

Improving the Teaching of Evidence-Based Practice: Challenges and Priorities

ERIC Educational Resources Information Center

Soydan, Haluk

2007-01-01

This article explores some of the main challenges of improving the teaching of evidence-based practice in schools of social work. The priority challenges are the needs for a general professional cultural shift, for adequate curricula, to overcome the controversy of scientific methodology, to better understand the state of the art of the…

Challenges of Postmodern Thought in Christian Higher Education Institutions: Implications for Ethical Leadership

ERIC Educational Resources Information Center

Darroux, Dean A.

2013-01-01

The study investigated the question: What is the process that Christian higher education administrators and faculty members used when understanding the challenges of postmodern thought at the institutions, and what are the challenges for ethical leadership? Utilizing a grounded theory methodology, the researcher sought to develop a theory that…

Ethiopian New Public Universities: Achievements, Challenges and Illustrative Case Studies

ERIC Educational Resources Information Center

van Deuren, Rita; Kahsu, Tsegazeab; Mohammed, Seid; Woldie, Wondimu

2016-01-01

Purpose: This paper aims to analyze and illustrate achievements and challenges of Ethiopian higher education, both at the system level and at the level of new public universities. Design/methodology/approach: Achievements and challenges at the system level are based on literature review and secondary data. Illustrative case studies are based on…

Methodological challenges of optical tweezers-based X-ray fluorescence imaging of biological model organisms at synchrotron facilities.

PubMed

Vergucht, Eva; Brans, Toon; Beunis, Filip; Garrevoet, Jan; Bauters, Stephen; De Rijcke, Maarten; Deruytter, David; Janssen, Colin; Riekel, Christian; Burghammer, Manfred; Vincze, Laszlo

2015-07-01

Recently, a radically new synchrotron radiation-based elemental imaging approach for the analysis of biological model organisms and single cells in their natural in vivo state was introduced. The methodology combines optical tweezers (OT) technology for non-contact laser-based sample manipulation with synchrotron radiation confocal X-ray fluorescence (XRF) microimaging for the first time at ESRF-ID13. The optical manipulation possibilities and limitations of biological model organisms, the OT setup developments for XRF imaging and the confocal XRF-related challenges are reported. In general, the applicability of the OT-based setup is extended with the aim of introducing the OT XRF methodology in all research fields where highly sensitive in vivo multi-elemental analysis is of relevance at the (sub)micrometre spatial resolution level.

Defining operational taxonomic units using DNA barcode data

PubMed Central

Blaxter, Mark; Mann, Jenna; Chapman, Tom; Thomas, Fran; Whitton, Claire; Floyd, Robin; Abebe, Eyualem

2005-01-01

Abstract The scale of diversity of life on this planet is a significant challenge for any scientific programme hoping to produce a complete catalogue, whatever means is used. For DNA barcoding studies, this difficulty is compounded by the realization that any chosen barcode sequence is not the gene ‘for’ speciation and that taxa have evolutionary histories. How are we to disentangle the confounding effects of reticulate population genetic processes? Using the DNA barcode data from meiofaunal surveys, here we discuss the benefits of treating the taxa defined by barcodes without reference to their correspondence to ‘species’, and suggest that using this non-idealist approach facilitates access to taxon groups that are not accessible to other methods of enumeration and classification. Major issues remain, in particular the methodologies for taxon discrimination in DNA barcode data. PMID:16214751

Outcome of the first Medicines Utilization Research in Africa group meeting to promote sustainable and rational medicine use in Africa.

PubMed

Massele, Amos; Burger, Johanita; Katende-Kyenda, Norah L; Kalemeera, Francis; Kenaope, Thatoyaone; Kibuule, Dan; Mbachu, Ogochukwu; Mubita, Mwangana; Oluka, Margaret; Olusanya, Adedunni; Paramadhas, Bene D Anand; van Zyl, Paulina; Godman, Brian

2015-01-01

The first Medicines Utilization Research in Africa group workshop and symposium brought researchers together from across Africa to improve their knowledge on drug utilization methodologies as well as exchange ideas. As a result, progress was made on drug utilization research and formulating future strategies to enhance the rational use of medicines in Africa. Anti-infectives were the principal theme for the 1-day symposium following the workshops. This included presentations on the inappropriate use of antibiotics as well as ways to address this. Concerns with adverse drug reactions and adherence to anti-retroviral medicines were also discussed, with poor adherence remaining a challenge. There were also concerns with the underutilization of generics. These discussions resulted in a number of agreed activities before the next conference in 2016.

Carotid interventions and blood pressure.

PubMed

Hirschl, Mirko; Kundi, Michael

2014-12-01

Arterial baroreceptors are pressure sensors found in the carotid sinus near the bifurcation of the carotid artery and in the aortic arch. Carotid interventions, whether endovascular or surgical, affect this complicated control system and the post-interventional blood pressure behavior. Comparisons between the intervention techniques, however, are challenging due to the varying measurement methods, duration of observation, and patient populations. The question as to which interventional method is preferable, if undisturbed regulation of blood pressure is concerned, still remains unanswered. The fact that blood pressure events (i.e., hemodynamic instability, hypertension, unstable blood pressure) frequently occur both immediately after intervention and in the long term, mandates a particularly careful cardiopulmonary and blood pressure monitoring. Direct and indirect measurements of baroreceptor sensitivity can be helpful in identifying high-risk patients, although the association to hard clinical endpoints is rarely documented for methodological reasons.

Life cycle assessment of lignocellulosic ethanol: a review of key factors and methods affecting calculated GHG emissions and energy use.

PubMed

Gerbrandt, Kelsey; Chu, Pei Lin; Simmonds, Allison; Mullins, Kimberley A; MacLean, Heather L; Griffin, W Michael; Saville, Bradley A

2016-04-01

Lignocellulosic ethanol has potential for lower life cycle greenhouse gas emissions compared to gasoline and conventional grain-based ethanol. Ethanol production 'pathways' need to meet economic and environmental goals. Numerous life cycle assessments of lignocellulosic ethanol have been published over the last 15 years, but gaps remain in understanding life cycle performance due to insufficient data, and model and methodological issues. We highlight key aspects of these issues, drawing on literature and a case study of corn stover ethanol. Challenges include the complexity of feedstock/ecosystems and market-mediated aspects and the short history of commercial lignocellulosic ethanol facilities, which collectively have led to uncertainty in GHG emissions estimates, and to debates on LCA methods and the role of uncertainty in decision making. Copyright © 2016 Elsevier Ltd. All rights reserved.

DFTB3: Extension of the self-consistent-charge density-functional tight-binding method (SCC-DFTB).

PubMed

Gaus, Michael; Cui, Qiang; Elstner, Marcus

2012-04-10

The self-consistent-charge density-functional tight-binding method (SCC-DFTB) is an approximate quantum chemical method derived from density functional theory (DFT) based on a second-order expansion of the DFT total energy around a reference density. In the present study we combine earlier extensions and improve them consistently with, first, an improved Coulomb interaction between atomic partial charges, and second, the complete third-order expansion of the DFT total energy. These modifications lead us to the next generation of the DFTB methodology called DFTB3, which substantially improves the description of charged systems containing elements C, H, N, O, and P, especially regarding hydrogen binding energies and proton affinities. As a result, DFTB3 is particularly applicable to biomolecular systems. Remaining challenges and possible solutions are also briefly discussed.

Cell-targetable DNA nanocapsules for spatiotemporal release of caged bioactive small molecules

NASA Astrophysics Data System (ADS)

Veetil, Aneesh T.; Chakraborty, Kasturi; Xiao, Kangni; Minter, Myles R.; Sisodia, Sangram S.; Krishnan, Yamuna

2017-12-01

Achieving triggered release of small molecules with spatial and temporal precision at designated cells within an organism remains a challenge. By combining a cell-targetable, icosahedral DNA-nanocapsule loaded with photoresponsive polymers, we show cytosolic delivery of small molecules with the spatial resolution of single endosomes in specific cells in Caenorhabditis elegans. Our technology can report on the extent of small molecules released after photoactivation as well as pinpoint the location at which uncaging of the molecules occurred. We apply this technology to release dehydroepiandrosterone (DHEA), a neurosteroid that promotes neurogenesis and neuron survival, and determined the timescale of neuronal activation by DHEA, using light-induced release of DHEA from targeted DNA nanocapsules. Importantly, sequestration inside the DNA capsule prevents photocaged DHEA from activating neurons prematurely. Our methodology can in principle be generalized to diverse neurostimulatory molecules.

Can Programming Frameworks Bring Smartphones into the Mainstream of Psychological Science?

PubMed Central

Piwek, Lukasz; Ellis, David A.

2016-01-01

Smartphones continue to provide huge potential for psychological science and the advent of novel research frameworks brings new opportunities for researchers who have previously struggled to develop smartphone applications. However, despite this renewed promise, smartphones have failed to become a standard item within psychological research. Here we consider the key issues that continue to limit smartphone adoption within psychological science and how these barriers might be diminishing in light of ResearchKit and other recent methodological developments. We conclude that while these programming frameworks are certainly a step in the right direction it remains challenging to create usable research-orientated applications with current frameworks. Smartphones may only become an asset for psychology and social science as a whole when development software that is both easy to use and secure becomes freely available. PMID:27602010

Biased and unbiased strategies to identify biologically active small molecules.

PubMed

Abet, Valentina; Mariani, Angelica; Truscott, Fiona R; Britton, Sébastien; Rodriguez, Raphaël

2014-08-15

Small molecules are central players in chemical biology studies. They promote the perturbation of cellular processes underlying diseases and enable the identification of biological targets that can be validated for therapeutic intervention. Small molecules have been shown to accurately tune a single function of pluripotent proteins in a reversible manner with exceptional temporal resolution. The identification of molecular probes and drugs remains a worthy challenge that can be addressed by the use of biased and unbiased strategies. Hypothesis-driven methodologies employs a known biological target to synthesize complementary hits while discovery-driven strategies offer the additional means of identifying previously unanticipated biological targets. This review article provides a general overview of recent synthetic frameworks that gave rise to an impressive arsenal of biologically active small molecules with unprecedented cellular mechanisms. Copyright © 2014. Published by Elsevier Ltd.

Enhancement in photoluminescence performance of carbon-decorated T-ZnO

NASA Astrophysics Data System (ADS)

Jian, Xian; Chen, Guozhang; Wang, Chao; Yin, Liangjun; Li, Gang; Yang, Ping; Chen, Lei; Xu, Bao; Gao, Yang; Feng, Yanyu; Tang, Hui; Luan, Chunhong; Liang, Yinglin; Jiang, Jing; Cao, Yu; Wang, Siyuan; Gao, Xin

2015-03-01

The facile preparation of ZnO possessing high visible luminescence intensity remains challenging due to an unclear luminescence mechanism. Here, two basic approaches are proposed to enhance the luminescent intensity based on the theoretical analysis over surface defects. Based on the deduction, we introduce a methodology for obtaining hybrid tetrapod-like zinc oxide (T-ZnO), decorated by carbon nanomarterials on T-ZnO surfaces through the catalytic chemical vapor deposition approach. The intensity of the T-ZnO green emission can be modulated by topography and the proportion of carbon. Under proper experiment conditions, the carbon decorating leads to dramatically enhanced luminescence intensity of T-ZnO from 400 to 700 nm compared with no carbon decorated, which elevates this approach to a simple and effective method for the betterment of fluorescent materials in practical applications.

Economical analysis of saturation mutagenesis experiments

PubMed Central

Acevedo-Rocha, Carlos G.; Reetz, Manfred T.; Nov, Yuval

2015-01-01

Saturation mutagenesis is a powerful technique for engineering proteins, metabolic pathways and genomes. In spite of its numerous applications, creating high-quality saturation mutagenesis libraries remains a challenge, as various experimental parameters influence in a complex manner the resulting diversity. We explore from the economical perspective various aspects of saturation mutagenesis library preparation: We introduce a cheaper and faster control for assessing library quality based on liquid media; analyze the role of primer purity and supplier in libraries with and without redundancy; compare library quality, yield, randomization efficiency, and annealing bias using traditional and emergent randomization schemes based on mixtures of mutagenic primers; and establish a methodology for choosing the most cost-effective randomization scheme given the screening costs and other experimental parameters. We show that by carefully considering these parameters, laboratory expenses can be significantly reduced. PMID:26190439

Scalable privacy-preserving data sharing methodology for genome-wide association studies: an application to iDASH healthcare privacy protection challenge.

PubMed

Yu, Fei; Ji, Zhanglong

2014-01-01

In response to the growing interest in genome-wide association study (GWAS) data privacy, the Integrating Data for Analysis, Anonymization and SHaring (iDASH) center organized the iDASH Healthcare Privacy Protection Challenge, with the aim of investigating the effectiveness of applying privacy-preserving methodologies to human genetic data. This paper is based on a submission to the iDASH Healthcare Privacy Protection Challenge. We apply privacy-preserving methods that are adapted from Uhler et al. 2013 and Yu et al. 2014 to the challenge's data and analyze the data utility after the data are perturbed by the privacy-preserving methods. Major contributions of this paper include new interpretation of the χ2 statistic in a GWAS setting and new results about the Hamming distance score, a key component for one of the privacy-preserving methods.

Scalable privacy-preserving data sharing methodology for genome-wide association studies: an application to iDASH healthcare privacy protection challenge

PubMed Central

2014-01-01

In response to the growing interest in genome-wide association study (GWAS) data privacy, the Integrating Data for Analysis, Anonymization and SHaring (iDASH) center organized the iDASH Healthcare Privacy Protection Challenge, with the aim of investigating the effectiveness of applying privacy-preserving methodologies to human genetic data. This paper is based on a submission to the iDASH Healthcare Privacy Protection Challenge. We apply privacy-preserving methods that are adapted from Uhler et al. 2013 and Yu et al. 2014 to the challenge's data and analyze the data utility after the data are perturbed by the privacy-preserving methods. Major contributions of this paper include new interpretation of the χ2 statistic in a GWAS setting and new results about the Hamming distance score, a key component for one of the privacy-preserving methods. PMID:25521367

Challenges in evaluating cancer as a clinical outcome in postapproval studies of drug safety

PubMed Central

Pinheiro, Simone P.; Rivera, Donna R.; Graham, David J.; Freedman, Andrew N.; Major, Jacqueline M.; Penberthy, Lynne; Levenson, Mark; Bradley, Marie C.; Wong, Hui-Lee; Ouellet-Hellstrom, Rita

2017-01-01

Pharmaceuticals approved in the United States are largely not known human carcinogens. However, cancer signals associated with pharmaceuticals may be hypothesized or arise after product approval. There are many study designs that can be used to evaluate cancer as an outcome in the postapproval setting. Because prospective systematic collection of cancer outcomes from a large number of individuals may be lengthy, expensive, and challenging, leveraging data from large existing databases are an integral approach. Such studies have the capability to evaluate the clinical experience of a large number of individuals, yet there are unique methodological challenges involved in their use to evaluate cancer outcomes. To discuss methodological challenges and potential solutions, the Food and Drug Administration and the National Cancer Institute convened a two-day public meeting in 2014. This commentary summarizes the most salient issues discussed at the meeting. PMID:27663208

Challenges in evaluating cancer as a clinical outcome in postapproval studies of drug safety.

PubMed

Pinheiro, Simone P; Rivera, Donna R; Graham, David J; Freedman, Andrew N; Major, Jacqueline M; Penberthy, Lynne; Levenson, Mark; Bradley, Marie C; Wong, Hui-Lee; Ouellet-Hellstrom, Rita

2016-11-01

Pharmaceuticals approved in the United States are largely not known human carcinogens. However, cancer signals associated with pharmaceuticals may be hypothesized or arise after product approval. There are many study designs that can be used to evaluate cancer as an outcome in the postapproval setting. Because prospective systematic collection of cancer outcomes from a large number of individuals may be lengthy, expensive, and challenging, leveraging data from large existing databases are an integral approach. Such studies have the capability to evaluate the clinical experience of a large number of individuals, yet there are unique methodological challenges involved in their use to evaluate cancer outcomes. To discuss methodological challenges and potential solutions, the Food and Drug Administration and the National Cancer Institute convened a two-day public meeting in 2014. This commentary summarizes the most salient issues discussed at the meeting. Published by Elsevier Inc.

Culturally appropriate methodology in obtaining a representative sample of South Australian Aboriginal adults for a cross-sectional population health study: challenges and resolutions.

PubMed

Marin, Tania; Taylor, Anne Winifred; Grande, Eleonora Dal; Avery, Jodie; Tucker, Graeme; Morey, Kim

2015-05-19

The considerably lower average life expectancy of Aboriginal and Torres Strait Islander Australians, compared with non-Aboriginal and non-Torres Strait Islander Australians, has been widely reported. Prevalence data for chronic disease and health risk factors are needed to provide evidence based estimates for Australian Aboriginal and Torres Strait Islanders population health planning. Representative surveys for these populations are difficult due to complex methodology. The focus of this paper is to describe in detail the methodological challenges and resolutions of a representative South Australian Aboriginal population-based health survey. Using a stratified multi-stage sampling methodology based on the Australian Bureau of Statistics 2006 Census with culturally appropriate and epidemiological rigorous methods, 11,428 randomly selected dwellings were approached from a total of 209 census collection districts. All persons eligible for the survey identified as Aboriginal and/or Torres Strait Islander and were selected from dwellings identified as having one or more Aboriginal person(s) living there at the time of the survey. Overall, the 399 interviews from an eligible sample of 691 SA Aboriginal adults yielded a response rate of 57.7%. These face-to-face interviews were conducted by ten interviewers retained from a total of 27 trained Aboriginal interviewers. Challenges were found in three main areas: identification and recruitment of participants; interviewer recruitment and retainment; and using appropriate engagement with communities. These challenges were resolved, or at least mainly overcome, by following local protocols with communities and their representatives, and reaching agreement on the process of research for Aboriginal people. Obtaining a representative sample of Aboriginal participants in a culturally appropriate way was methodologically challenging and required high levels of commitment and resources. Adhering to these principles has resulted in a rich and unique data set that provides an overview of the self-reported health status for Aboriginal people living in South Australia. This process provides some important principles to be followed when engaging with Aboriginal people and their communities for the purpose of health research.

Challenges to Military Operations in Support of U.S. Interests. Volume 2: Main Report

DTIC Science & Technology

2008-12-01

Challenges to Military Operations in Support of U.S. Interests U.S. conventional military capability remains unmatched by any state. As a result, nations...greater importance. PR EF AC E I xiii Preface U.S. conventional military capability remains unmatched by any state. U.S...scope of the study remained robust, presenting the challenge of how to approach the investigation into U.S. capabilities, capability gaps, and

Quality and methodological challenges in Internet-based mental health trials.

PubMed

Ye, Xibiao; Bapuji, Sunita Bayyavarapu; Winters, Shannon; Metge, Colleen; Raynard, Mellissa

2014-08-01

To review the quality of Internet-based mental health intervention studies and their methodological challenges. We searched multiple literature databases to identify relevant studies according to the Population, Interventions, Comparators, Outcomes, and Study Design framework. Two reviewers independently assessed selection bias, allocation bias, confounding bias, blinding, data collection methods, and withdrawals/dropouts, using the Quality Assessment Tool for Quantitative Studies. We rated each component as strong, moderate, or weak and assigned a global rating (strong, moderate, or weak) to each study. We discussed methodological issues related to the study quality. Of 122 studies included, 31 (25%), 44 (36%), and 47 (39%) were rated strong, moderate, and weak, respectively. Only five studies were rated strong for all of the six quality components (three of them were published by the same group). Lack of blinding, selection bias, and low adherence were the top three challenges in Internet-based mental health intervention studies. The overall quality of Internet-based mental health intervention needs to improve. In particular, studies need to improve sample selection, intervention allocation, and blinding.

Toward a Framework for Comparative HRD Research

ERIC Educational Resources Information Center

Wang, Greg G.; Sun, Judy Y.

2012-01-01

Purpose: This paper seeks to address the recent challenges in the international human resource development (HRD) research and the related methodological strategy. Design/methodology/approach: This inquiry is based on a survey of literatures and integrates various comparative research strategies adopted in other major social science disciplines.…

METHODOLOGICAL ISSUES IN HUMAN EXPOSURE STUDIES OF LOW LEVEL SOLVENT MIXTURES

EPA Science Inventory

The design of appropriate studies to assess the sensory irritant and neurobehavioral-effects of exposure to complex VOC mixtures poses a variety of methodological challenges, particularly at the low levels found in new buildings. or instance, Otto et al (1989) exposed subjects to...

Educational Policymaking and the Methodology of Positive Economics: A Theoretical Critique

ERIC Educational Resources Information Center

Gilead, Tal

2014-01-01

By critically interrogating the methodological foundations of orthodox economic theory, Tal Gilead challenges the growing conviction in educational policymaking quarters that, being more scientific than other forms of educational investigation, inquiries grounded in orthodox economics should provide the basis for educational policymaking. He…

Structural Equation Modeling of School Violence Data: Methodological Considerations

ERIC Educational Resources Information Center

Mayer, Matthew J.

2004-01-01

Methodological challenges associated with structural equation modeling (SEM) and structured means modeling (SMM) in research on school violence and related topics in the social and behavioral sciences are examined. Problems associated with multiyear implementations of large-scale surveys are discussed. Complex sample designs, part of any…

Performance evaluation in full-mission simulation - Methodological advances and research challenges. [in air transport operations

NASA Technical Reports Server (NTRS)

Chidester, Thomas R.; Kanki, Barbara G.; Helmreich, Robert L.

1989-01-01

The crew-factors research program at NASA Ames has developed a methodology for studying the impact of a variety of variables on the effectiveness of crews flying realistic but high workload simulated trips. The validity of investigations using the methodology is enhanced by careful design of full-mission scenarios, performance assessment using converging sources of data, and recruitment of representative subjects. Recently, portions of this methodology have been adapted for use in assessing the effectiveness of crew coordination among participants in line-oriented flight training.

Getting People Involved: The Benefit of Intellectual Capital Management for Addressing HR Challenges

ERIC Educational Resources Information Center

Pook, Katja

2011-01-01

Purpose: This paper aims to explore the benefits of intellectual capital assessment for facing current challenges of human resources work and organizational development. Design/methodology/approach: The paper takes findings of studies on challenges in HR work and maps them with features of intellectual capital assessment methods. It is thus a…

Exhaustively sampling peptide adsorption with metadynamics.

PubMed

Deighan, Michael; Pfaendtner, Jim

2013-06-25

Simulating the adsorption of a peptide or protein and obtaining quantitative estimates of thermodynamic observables remains challenging for many reasons. One reason is the dearth of molecular scale experimental data available for validating such computational models. We also lack simulation methodologies that effectively address the dual challenges of simulating protein adsorption: overcoming strong surface binding and sampling conformational changes. Unbiased classical simulations do not address either of these challenges. Previous attempts that apply enhanced sampling generally focus on only one of the two issues, leaving the other to chance or brute force computing. To improve our ability to accurately resolve adsorbed protein orientation and conformational states, we have applied the Parallel Tempering Metadynamics in the Well-Tempered Ensemble (PTMetaD-WTE) method to several explicitly solvated protein/surface systems. We simulated the adsorption behavior of two peptides, LKα14 and LKβ15, onto two self-assembled monolayer (SAM) surfaces with carboxyl and methyl terminal functionalities. PTMetaD-WTE proved effective at achieving rapid convergence of the simulations, whose results elucidated different aspects of peptide adsorption including: binding free energies, side chain orientations, and preferred conformations. We investigated how specific molecular features of the surface/protein interface change the shape of the multidimensional peptide binding free energy landscape. Additionally, we compared our enhanced sampling technique with umbrella sampling and also evaluated three commonly used molecular dynamics force fields.

Health disparities, social injustice, and the culture of nursing.

PubMed

Giddings, Lynne S

2005-01-01

Nurses are well positioned to challenge institutionalized social injustices that lead to health disparities. The aim of this cross-cultural study was to collect stories of difference and fairness within nursing. The study used a life history methodology informed by feminist theory and critical social theory. Life story interviews were conducted with 26 women nurses of varying racial, cultural, sexual identity, and specialty backgrounds in the United States (n = 13) and Aotearoa New Zealand (n = 13). Participants reported having some understanding of social justice issues. They were asked to reflect on their experience of difference and fairness in their lives and specifically within nursing. Their stories were analyzed using a life history immersion method. Nursing remains attached to the ideological construction of the "White good nurse." Taken-for-granted ideals privilege those who fit in and marginalize those who do not. The nurses experienced discrimination and unfairness, survived by living in two worlds, learned to live in contradiction, and worked surreptitiously for social justice. For nurses to contribute to changing the systems and structures that maintain health disparities, the privilege of not seeing difference and the processes of mainstream violence that support the construction of the "White good nurse" must be challenged. Nurses need skills to deconstruct the marginalizing social processes that sustain inequalities in nursing and healthcare. These hidden realities--racism, sexism, heterosexism, and other forms of discrimination--will then be made visible and open to challenge.

Challenges in the estimation of Net SURvival: The CENSUR working survival group.

PubMed

Giorgi, R

2016-10-01

Net survival, the survival probability that would be observed, in a hypothetical world, where the cancer of interest would be the only possible cause of death, is a key indicator in population-based cancer studies. Accounting for mortality due to other causes, it allows cross-country comparisons or trends analysis and provides a useful indicator for public health decision-making. The objective of this study was to show how the creation and formalization of a network comprising established research teams, which already had substantial and complementary experience in both cancer survival analysis and methodological development, make it possible to meet challenges and thus provide more adequate tools, to improve the quality and the comparability of cancer survival data, and to promote methodological transfers in areas of emerging interest. The Challenges in the Estimation of Net SURvival (CENSUR) working survival group is composed of international researchers highly skilled in biostatistics, methodology, and epidemiology, from different research organizations in France, the United Kingdom, Italy, Slovenia, and Canada, and involved in French (FRANCIM) and European (EUROCARE) cancer registry networks. The expected advantages are an interdisciplinary, international, synergistic network capable of addressing problems in public health, for decision-makers at different levels; tools for those in charge of net survival analyses; a common methodology that makes unbiased cross-national comparisons of cancer survival feasible; transfer of methods for net survival estimations to other specific applications (clinical research, occupational epidemiology); and dissemination of results during an international training course. The formalization of the international CENSUR working survival group was motivated by a need felt by scientists conducting population-based cancer research to discuss, develop, and monitor implementation of a common methodology to analyze net survival in order to provide useful information for cancer control and cancer policy. A "team science" approach is necessary to address new challenges concerning the estimation of net survival. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Methodological, political and legal issues in the assessment of the effects of nanotechnology on human health.

PubMed

Guseva Canu, Irina; Schulte, Paul A; Riediker, Michael; Fatkhutdinova, Liliya; Bergamaschi, Enrico

2018-02-01

Engineered nanomaterials (ENMs) raise questions among the scientific community and public health authorities about their potential risks to human health. Studying a prospective cohort of workers exposed to ENMs would be considered the gold standard for identifying potential health effects of nanotechnology and confirming the 'no effect' levels derived from cellular and animal models. However, because only small, cross-sectional studies have been conducted in the past 5 years, questions remain about the health risks of ENMs. This essay addresses the scientific, methodological, political and regulatory issues that make epidemiological research in nanotechnology-exposed communities particularly complex. Scientific challenges include the array of physicochemical parameters and ENM production conditions, the lack of universally accepted definitions of ENMs and nanotechnology workers, and the lack of information about modes of action, target organs and likely dose-response functions of ENMs. Standardisation of data collection and harmonisation of research protocols are needed to eliminate misclassification of exposures and health effects. Forming ENM worker cohorts from a combination of smaller cohorts and overcoming selection bias are also challenges. National or international registries for monitoring the exposures and health of ENM workers would be helpful for epidemiological studies, but the creation of such a registry and ENM worker cohorts will require political support and dedicated funding at the national and international levels. Public authorities and health agencies should consider carrying out an ENM awareness campaign to educate and engage all stakeholders and concerned communities in discussion of such a project. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

A new scheme for urban impervious surface classification from SAR images

NASA Astrophysics Data System (ADS)

Zhang, Hongsheng; Lin, Hui; Wang, Yunpeng

2018-05-01

Urban impervious surfaces have been recognized as a significant indicator for various environmental and socio-economic studies. There is an increasingly urgent demand for timely and accurate monitoring of the impervious surfaces with satellite technology from local to global scales. In the past decades, optical remote sensing has been widely employed for this task with various techniques. However, there are still a range of challenges, e.g. handling cloud contamination on optical data. Therefore, the Synthetic Aperture Radar (SAR) was introduced for the challenging task because it is uniquely all-time- and all-weather-capable. Nevertheless, with an increasing number of SAR data applied, the methodology used for impervious surfaces classification remains unchanged from the methods used for optical datasets. This shortcoming has prevented the community from fully exploring the potential of using SAR data for impervious surfaces classification. We proposed a new scheme that is comparable to the well-known and fundamental Vegetation-Impervious surface-Soil (V-I-S) model for mapping urban impervious surfaces. Three scenes of fully polarimetric Radsarsat-2 data for the cities of Shenzhen, Hong Kong and Macau were employed to test and validate the proposed methodology. Experimental results indicated that the overall accuracy and Kappa coefficient were 96.00% and 0.8808 in Shenzhen, 93.87% and 0.8307 in Hong Kong and 97.48% and 0.9354 in Macau, indicating the applicability and great potential of the new scheme for impervious surfaces classification using polarimetric SAR data. Comparison with the traditional scheme indicated that this new scheme was able to improve the overall accuracy by up to 4.6% and Kappa coefficient by up to 0.18.

Verification of Agricultural Methane Emission Inventories

NASA Astrophysics Data System (ADS)

Desjardins, R. L.; Pattey, E.; Worth, D. E.; VanderZaag, A.; Mauder, M.; Srinivasan, R.; Worthy, D.; Sweeney, C.; Metzger, S.

2017-12-01

It is estimated that agriculture contributes more than 40% of anthropogenic methane (CH4) emissions in North America. However, these estimates, which are either based on the Intergovernmental Panel on Climate Change (IPCC) methodology or inverse modeling techniques, are poorly validated due to the challenges of separating interspersed CH4 sources within agroecosystems. A flux aircraft, instrumented with a fast-response Picarro CH4 analyzer for the eddy covariance (EC) technique and a sampling system for the relaxed eddy accumulation technique (REA), was flown at an altitude of about 150 m along several 20-km transects over an agricultural region in Eastern Canada. For all flight days, the top-down CH4 flux density measurements were compared to the footprint adjusted bottom-up estimates based on an IPCC Tier II methodology. Information on the animal population, land use type and atmospheric and surface variables were available for each transect. Top-down and bottom-up estimates of CH4 emissions were found to be poorly correlated, and wetlands were the most frequent confounding source of CH4; however, there were other sources such as waste treatment plants and biodigesters. Spatially resolved wavelet covariance estimates of CH4 emissions helped identify the contribution of wetlands to the overall CH4 flux, and the dependence of these emissions on temperature. When wetland contribution in the flux footprint was minimized, top-down and bottom-up estimates agreed to within measurement error. This research demonstrates that although existing aircraft-based technology can be used to verify regional ( 100 km2) agricultural CH4 emissions, it remains challenging due to diverse sources of CH4 present in many regions. The use of wavelet covariance to generate spatially-resolved flux estimates was found to be the best way to separate interspersed sources of CH4.

Methodological Challenges in Cross-Language Qualitative Research: A Research Review

PubMed Central

Squires, Allison

2009-01-01

Objectives Cross-language qualitative research occurs when a language barrier is present between researchers and participants. The language barrier is frequently mediated through the use of a translator or interpreter. The purpose of this critical review of cross-language qualitative research was three fold: 1) review the methods literature addressing cross language research; 2) synthesize the methodological recommendations from the literature into a list of criteria that could evaluate how researchers methodologically managed translators and interpreters in their qualitative studies; and 3) test these criteria on published cross-language qualitative studies. Data sources A group of 40 purposively selected cross-language qualitative studies found in nursing and health sciences journals. Review methods The synthesis of the cross-language methods literature produced 14 criteria to evaluate how qualitative researchers managed the language barrier between themselves and their study participants. To test the criteria, the researcher conducted a summative content analysis framed by discourse analysis techniques of the 40 cross-language studies. Results The evaluation showed that only 6 out of 40 studies met all the criteria recommended by the cross-language methods literature for the production of trustworthy results in cross-language qualitative studies. Multiple inconsistencies, reflecting disadvantageous methodological choices by cross-language researchers, appeared in the remaining 33 studies. To name a few, these included rendering the translator or interpreter as an invisible part of the research process, failure to pilot test interview questions in the participant’s language, no description of translator or interpreter credentials, failure to acknowledge translation as a limitation of the study, and inappropriate methodological frameworks for cross-language research. Conclusions The finding about researchers making the role of the translator or interpreter invisible during the research process supports studies completed by other authors examining this issue. The analysis demonstrated that the criteria produced by this study may provide useful guidelines for evaluating cross-language research and for novice cross-language researchers designing their first studies. Finally, the study also indicates that researchers attempting cross-language studies need to address the methodological issues surrounding language barriers between researchers and participants more systematically. PMID:18789799

Independent predictors of reliability between full time employee-dependent acquisition of functional outcomes compared to non-full time employee-dependent methodologies: a prospective single institutional study.

PubMed

Adogwa, Owoicho; Elsamadicy, Aladine A; Cheng, Joseph; Bagley, Carlos

2016-03-01

The prospective acquisition of reliable patient-reported outcomes (PROs) measures demonstrating the effectiveness of spine surgery, or lack thereof, remains a challenge. The aims of this study are to compare the reliability of functional outcomes metrics obtained using full time employee (FTE) vs. non-FTE-dependent methodologies and to determine the independent predictors of response reliability using non FTE-dependent methodologies. One hundred and nineteen adult patients (male: 65, female: 54) undergoing one- and two-level lumbar fusions at Duke University Medical Center were enrolled in this prospective study. Enrollment criteria included available demographic, clinical and baseline functional outcomes data. All patients were administered two similar sets of baseline questionnaires-(I) phone interviews (FTE-dependent) and (II) hardcopy in clinic (patient self-survey, non-FTE-dependent). All patients had at least a two-week washout period between phone interviews and in-clinic self-surveys to minimize effect of recall. Questionnaires included Oswestry disability index (ODI) and Visual Analog Back and Leg Pain Scale (VAS-BP/LP). Reliability was assessed by the degree to which patient responses to baseline questionnaires differed between both time points. About 26.89% had a history an anxiety disorder and 28.57% reported a history of depression. At least 97.47% of patients had a High School Diploma or GED, with 49.57% attaining a 4-year college degree or post-graduate degree. 29.94% reported full-time employment and 14.28% were on disability. There was a very high correlation between baseline PRO's data captured between FTE-dependent compared to non-FTE-dependent methodologies (r=0.89). In a multivariate logistic regression model, the absence of anxiety and depression, higher levels of education (college or greater) and full-time employment, were independently associated with high response reliability using non-FTE-dependent methodologies. Our study suggests that capturing health-related quality of life data using non-FTE-dependent methodologies is highly reliable and maybe a more cost-effective alternative. Well-educated patients who are employed full-time appear to be the most reliable.

Methodological challenges in cross-language qualitative research: a research review.

PubMed

Squires, Allison

2009-02-01

Cross-language qualitative research occurs when a language barrier is present between researchers and participants. The language barrier is frequently mediated through the use of a translator or interpreter. The purpose of this analysis of cross-language qualitative research was threefold: (1) review the methods literature addressing cross-language research; (2) synthesize the methodological recommendations from the literature into a list of criteria that could evaluate how researchers methodologically managed translators and interpreters in their qualitative studies; (3) test these criteria on published cross-language qualitative studies. A group of 40 purposively selected cross-language qualitative studies found in nursing and health sciences journals. The synthesis of the cross-language methods literature produced 14 criteria to evaluate how qualitative researchers managed the language barrier between themselves and their study participants. To test the criteria, the researcher conducted a summative content analysis framed by discourse analysis techniques of the 40 cross-language studies. The evaluation showed that only 6 out of 40 studies met all the criteria recommended by the cross-language methods literature for the production of trustworthy results in cross-language qualitative studies. Multiple inconsistencies, reflecting disadvantageous methodological choices by cross-language researchers, appeared in the remaining 33 studies. To name a few, these included rendering the translator or interpreter as an invisible part of the research process, failure to pilot test interview questions in the participant's language, no description of translator or interpreter credentials, failure to acknowledge translation as a limitation of the study, and inappropriate methodological frameworks for cross-language research. The finding about researchers making the role of the translator or interpreter invisible during the research process supports studies completed by other authors examining this issue. The analysis demonstrated that the criteria produced by this study may provide useful guidelines for evaluating cross-language research and for novice cross-language researchers designing their first studies. Finally, the study also indicates that researchers attempting cross-language studies need to address the methodological issues surrounding language barriers between researchers and participants more systematically.

Language barriers and qualitative nursing research: methodological considerations.

PubMed

Squires, A

2008-09-01

This review of the literature synthesizes methodological recommendations for the use of translators and interpreters in cross-language qualitative research. Cross-language qualitative research involves the use of interpreters and translators to mediate a language barrier between researchers and participants. Qualitative nurse researchers successfully address language barriers between themselves and their participants when they systematically plan for how they will use interpreters and translators throughout the research process. Experienced qualitative researchers recognize that translators can generate qualitative data through translation processes and by participating in data analysis. Failure to address language barriers and the methodological challenges they present threatens the credibility, transferability, dependability and confirmability of cross-language qualitative nursing research. Through a synthesis of the cross-language qualitative methods literature, this article reviews the basics of language competence, translator and interpreter qualifications, and roles for each kind of qualitative research approach. Methodological and ethical considerations are also provided. By systematically addressing the methodological challenges cross-language research presents, nurse researchers can produce better evidence for nursing practice and policy making when working across different language groups. Findings from qualitative studies will also accurately represent the experiences of the participants without concern that the meaning was lost in translation.

Language barriers and qualitative nursing research: methodological considerations

PubMed Central

Squires, A.

2009-01-01

Aim This review of the literature synthesizes methodological recommendations for the use of translators and interpreters in cross-language qualitative research. Background Cross-language qualitative research involves the use of interpreters and translators to mediate a language barrier between researchers and participants. Qualitative nurse researchers successfully address language barriers between themselves and their participants when they systematically plan for how they will use interpreters and translators throughout the research process. Experienced qualitative researchers recognize that translators can generate qualitative data through translation processes and by participating in data analysis. Failure to address language barriers and the methodological challenges they present threatens the credibility, transferability, dependability and confirmability of cross-language qualitative nursing research. Through a synthesis of the cross-language qualitative methods literature, this article reviews the basics of language competence, translator and interpreter qualifications, and roles for each kind of qualitative research approach. Methodological and ethical considerations are also provided. Conclusion By systematically addressing the methodological challenges cross-language research presents, nurse researchers can produce better evidence for nursing practice and policy making when working across different language groups. Findings from qualitative studies will also accurately represent the experiences of the participants without concern that the meaning was lost in translation. PMID:19522941

Issues surrounding the health economic evaluation of genomic technologies

PubMed Central

Buchanan, James; Wordsworth, Sarah; Schuh, Anna

2014-01-01

Aim Genomic interventions could enable improved disease stratification and individually tailored therapies. However, they have had a limited impact on clinical practice to date due to a lack of evidence, particularly economic evidence. This is partly because health economists are yet to reach consensus on whether existing methods are sufficient to evaluate genomic technologies. As different approaches may produce conflicting adoption decisions, clarification is urgently required. This article summarizes the methodological issues associated with conducting economic evaluations of genomic interventions. Materials & methods A structured literature review was conducted to identify references that considered the methodological challenges faced when conducting economic evaluations of genomic interventions. Results Methodological challenges related to the analytical approach included the choice of comparator, perspective and timeframe. Challenges in costing centered around the need to collect a broad range of costs, frequently, in a data-limited environment. Measuring outcomes is problematic as standard measures have limited applicability, however, alternative metrics (e.g., personal utility) are underdeveloped and alternative approaches (e.g., cost–benefit analysis) underused. Effectiveness data quality is weak and challenging to incorporate into standard economic analyses, while little is known about patient and clinician behavior in this context. Comprehensive value of information analyses are likely to be helpful. Conclusion Economic evaluations of genomic technologies present a particular challenge for health economists. New methods may be required to resolve these issues, but the evidence to justify alternative approaches is yet to be produced. This should be the focus of future work in this field. PMID:24236483

Methodological challenges in qualitative content analysis: A discussion paper.

PubMed

Graneheim, Ulla H; Lindgren, Britt-Marie; Lundman, Berit

2017-09-01

This discussion paper is aimed to map content analysis in the qualitative paradigm and explore common methodological challenges. We discuss phenomenological descriptions of manifest content and hermeneutical interpretations of latent content. We demonstrate inductive, deductive, and abductive approaches to qualitative content analysis, and elaborate on the level of abstraction and degree of interpretation used in constructing categories, descriptive themes, and themes of meaning. With increased abstraction and interpretation comes an increased challenge to demonstrate the credibility and authenticity of the analysis. A key issue is to show the logic in how categories and themes are abstracted, interpreted, and connected to the aim and to each other. Qualitative content analysis is an autonomous method and can be used at varying levels of abstraction and interpretation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Commentary: An Asian Americanist Perspective on Child Development.

PubMed

Lee, Richard M; Y J Kim, Adam; Zhou, Xiang

2016-07-01

In this commentary, we put forth an Asian Americanist perspective on child development that frames, expands upon, and at times challenges the contextual, conceptual, and methodological ideas put forward by Kiang et al., Mistry et al., and Yoshikawa et al. (this volume). This Asian Americanist perspective draws upon scholarship in Asian American Studies and critical race theory to bridge the historical, conceptual, and methodological contributions of the three articles. We also aim to challenge current and future generations of scholars studying Asian American child development to look at Asian American youth and families as autonomous, self-determining agents who are capable of challenging, resisting, and affecting change in a racialized society. © 2016 The Authors. Child Development © 2016 Society for Research in Child Development, Inc.

Studying depression using imaging and machine learning methods.

PubMed

Patel, Meenal J; Khalaf, Alexander; Aizenstein, Howard J

2016-01-01

Depression is a complex clinical entity that can pose challenges for clinicians regarding both accurate diagnosis and effective timely treatment. These challenges have prompted the development of multiple machine learning methods to help improve the management of this disease. These methods utilize anatomical and physiological data acquired from neuroimaging to create models that can identify depressed patients vs. non-depressed patients and predict treatment outcomes. This article (1) presents a background on depression, imaging, and machine learning methodologies; (2) reviews methodologies of past studies that have used imaging and machine learning to study depression; and (3) suggests directions for future depression-related studies.

Methodologies for Verification and Validation of Space Launch System (SLS) Structural Dynamic Models: Appendices

NASA Technical Reports Server (NTRS)

Coppolino, Robert N.

2018-01-01

Verification and validation (V&V) is a highly challenging undertaking for SLS structural dynamics models due to the magnitude and complexity of SLS subassemblies and subassemblies. Responses to challenges associated with V&V of Space Launch System (SLS) structural dynamics models are presented in Volume I of this paper. Four methodologies addressing specific requirements for V&V are discussed. (1) Residual Mode Augmentation (RMA). (2) Modified Guyan Reduction (MGR) and Harmonic Reduction (HR, introduced in 1976). (3) Mode Consolidation (MC). Finally, (4) Experimental Mode Verification (EMV). This document contains the appendices to Volume I.

How bootstrap can help in forecasting time series with more than one seasonal pattern

NASA Astrophysics Data System (ADS)

Cordeiro, Clara; Neves, M. Manuela

2012-09-01

The search for the future is an appealing challenge in time series analysis. The diversity of forecasting methodologies is inevitable and is still in expansion. Exponential smoothing methods are the launch platform for modelling and forecasting in time series analysis. Recently this methodology has been combined with bootstrapping revealing a good performance. The algorithm (Boot. EXPOS) using exponential smoothing and bootstrap methodologies, has showed promising results for forecasting time series with one seasonal pattern. In case of more than one seasonal pattern, the double seasonal Holt-Winters methods and the exponential smoothing methods were developed. A new challenge was now to combine these seasonal methods with bootstrap and carry over a similar resampling scheme used in Boot. EXPOS procedure. The performance of such partnership will be illustrated for some well-know data sets existing in software.

Methodological Challenges in Physical Activity Research with Older Adults

PubMed Central

Chase, Jo-Ana D.

2015-01-01

The aging adult population is growing, as well as the incidence of chronic illness among older adults. Physical activity has been demonstrated in the literature to be a beneficial component of self-management for chronic illnesses commonly found in the older adult population. Health sciences research seeks to develop new knowledge, practices, and policies that may benefit older adults’ management of chronic illness and quality of life. However, research with the older adult population, though beneficial, includes potential methodological challenges specific to this age group. This article discusses common methodological issues in research among older adults, with a focus on physical activity intervention studies. Awareness and understanding of these issues may facilitate future development of research studies devoted to the aging adult population, through appropriate modification and tailoring of sampling techniques, intervention development, and data measures and collection. PMID:21821726

Toward a Hermeneutical Theory of International Human Rights Education

ERIC Educational Resources Information Center

Al-Daraweesh, Fuad; Snauwaert, Dale T.

2013-01-01

The purpose of this essay is to articulate and defend the epistemological foundations of international human rights education from the perspective of a hermeneutical interpretive methodology. Fuad Al-Daraweesh and Dale Snauwaert argue here that this methodology potentially alleviates the challenges that face the cross-cultural implementation of…

Using Counter-Stories to Challenge Stock Stories about Traveller Families

ERIC Educational Resources Information Center

D'Arcy, Kate

2017-01-01

Critical Race Theory (CRT) is formed from a series of different methodological tools to expose and address racism and discrimination. Counter-stories are one of these tools. This article considers the potential of counter-stories as a methodological, theoretical and practical tool to analyse existing educational inequalities for Traveller…

Single-Case Experimental Designs: A Systematic Review of Published Research and Current Standards

ERIC Educational Resources Information Center

Smith, Justin D.

2012-01-01

This article systematically reviews the research design and methodological characteristics of single-case experimental design (SCED) research published in peer-reviewed journals between 2000 and 2010. SCEDs provide researchers with a flexible and viable alternative to group designs with large sample sizes. However, methodological challenges have…

Reengineering the Acquisition/Procurement Process: A Methodology for Requirements Collection

NASA Technical Reports Server (NTRS)

Taylor, Randall; Vanek, Thomas

2011-01-01

This paper captures the systematic approach taken by JPL's Acquisition Reengineering Project team, the methodology used, challenges faced, and lessons learned. It provides pragmatic "how-to" techniques and tools for collecting requirements and for identifying areas of improvement in an acquisition/procurement process or other core process of interest.

Culturally Competent Social Work Research: Methodological Considerations for Research with Language Minorities

ERIC Educational Resources Information Center

Casado, Banghwa Lee; Negi, Nalini Junko; Hong, Michin

2012-01-01

Despite the growing number of language minorities, foreign-born individuals with limited English proficiency, this population has been largely left out of social work research, often due to methodological challenges involved in conducting research with this population. Whereas the professional standard calls for cultural competence, a discussion…

Problem-Based Learning: Lessons for Administrators, Educators and Learners

ERIC Educational Resources Information Center

Yeo, Roland

2005-01-01

Purpose: The paper aims to explore the challenges of problem-based learning (PBL) as an unconventional teaching methodology experienced by a higher learning institute in Singapore. Design/methodology/approach: The exploratory study was conducted using focus group discussions and semi-structured interviews. Four groups of people were invited to…

75 FR 81533 - Antidumping Proceedings: Calculation of the Weighted Average Dumping Margin and Assessment Rate...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-28

... non-dumped comparisons. Several World Trade Organization (``WTO'') dispute settlement reports have... methodologies have been challenged as being inconsistent with the World Trade Organization (``WTO'') General... comparisons in reviews in a manner that parallels the WTO-consistent methodology the Department currently...

Beyond Compliance Checking: A Situated Approach to Visual Research Ethics.

PubMed

Lenette, Caroline; Botfield, Jessica R; Boydell, Katherine; Haire, Bridget; Newman, Christy E; Zwi, Anthony B

2018-03-19

Visual research methods like photography and digital storytelling are increasingly used in health and social sciences research as participatory approaches that benefit participants, researchers, and audiences. Visual methods involve a number of additional ethical considerations such as using identifiable content and ownership of creative outputs. As such, ethics committees should use different assessment frameworks to consider research protocols with visual methods. Here, we outline the limitations of ethics committees in assessing projects with a visual focus and highlight the sparse knowledge on how researchers respond when they encounter ethical challenges in the practice of visual research. We propose a situated approach in relation to visual methodologies that encompasses a negotiated, flexible approach, given that ethical issues usually emerge in relation to the specific contexts of individual research projects. Drawing on available literature and two case studies, we identify and reflect on nuanced ethical implications in visual research, like tensions between aesthetics and research validity. The case studies highlight strategies developed in-situ to address the challenges two researchers encountered when using visual research methods, illustrating that some practice implications are not necessarily addressed using established ethical clearance procedures. A situated approach can ensure that visual research remains ethical, engaging, and rigorous.

Computer-aided biochemical programming of synthetic microreactors as diagnostic devices.

PubMed

Courbet, Alexis; Amar, Patrick; Fages, François; Renard, Eric; Molina, Franck

2018-04-26

Biological systems have evolved efficient sensing and decision-making mechanisms to maximize fitness in changing molecular environments. Synthetic biologists have exploited these capabilities to engineer control on information and energy processing in living cells. While engineered organisms pose important technological and ethical challenges, de novo assembly of non-living biomolecular devices could offer promising avenues toward various real-world applications. However, assembling biochemical parts into functional information processing systems has remained challenging due to extensive multidimensional parameter spaces that must be sampled comprehensively in order to identify robust, specification compliant molecular implementations. We introduce a systematic methodology based on automated computational design and microfluidics enabling the programming of synthetic cell-like microreactors embedding biochemical logic circuits, or protosensors , to perform accurate biosensing and biocomputing operations in vitro according to temporal logic specifications. We show that proof-of-concept protosensors integrating diagnostic algorithms detect specific patterns of biomarkers in human clinical samples. Protosensors may enable novel approaches to medicine and represent a step toward autonomous micromachines capable of precise interfacing of human physiology or other complex biological environments, ecosystems, or industrial bioprocesses. © 2018 The Authors. Published under the terms of the CC BY 4.0 license.

Genetic Inventory Task Final Report. Volume 2

NASA Technical Reports Server (NTRS)

Venkateswaran, Kasthuri; LaDuc, Myron T.; Vaishampayan, Parag

2012-01-01

Contaminant terrestrial microbiota could profoundly impact the scientific integrity of extraterrestrial life-detection experiments. It is therefore important to know what organisms persist on spacecraft surfaces so that their presence can be eliminated or discriminated from authentic extraterrestrial biosignatures. Although there is a growing understanding of the biodiversity associated with spacecraft and cleanroom surfaces, it remains challenging to assess the risk of these microbes confounding life-detection or sample-return experiments. A key challenge is to provide a comprehensive inventory of microbes present on spacecraft surfaces. To assess the phylogenetic breadth of microorganisms on spacecraft and associated surfaces, the Genetic Inventory team used three technologies: conventional cloning techniques, PhyloChip DNA microarrays, and 454 tag-encoded pyrosequencing, together with a methodology to systematically collect, process, and archive nucleic acids. These three analysis methods yielded considerably different results: Traditional approaches provided the least comprehensive assessment of microbial diversity, while PhyloChip and pyrosequencing illuminated more diverse microbial populations. The overall results stress the importance of selecting sample collection and processing approaches based on the desired target and required level of detection. The DNA archive generated in this study can be made available to future researchers as genetic-inventory-oriented technologies further mature.

Are three generations of quantitative molecular methods sufficient in medical virology? Brief review.

PubMed

Clementi, Massimo; Bagnarelli, Patrizia

2015-10-01

In the last two decades, development of quantitative molecular methods has characterized the evolution of clinical virology more than any other methodological advancement. Using these methods, a great deal of studies has addressed efficiently in vivo the role of viral load, viral replication activity, and viral transcriptional profiles as correlates of disease outcome and progression, and has highlighted the physio-pathology of important virus diseases of humans. Furthermore, these studies have contributed to a better understanding of virus-host interactions and have sharply revolutionized the research strategies in basic and medical virology. In addition and importantly from a medical point of view, quantitative methods have provided a rationale for the therapeutic intervention and therapy monitoring in medically important viral diseases. Despite the advances in technology and the development of three generations of molecular methods within the last two decades (competitive PCR, real-time PCR, and digital PCR), great challenges still remain for viral testing related not only to standardization, accuracy, and precision, but also to selection of the best molecular targets for clinical use and to the identification of thresholds for risk stratification and therapeutic decisions. Future research directions, novel methods and technical improvements could be important to address these challenges.

"Bulk" Nanocrystalline Metals: Review of the Current State of the Art and Future Opportunities for Copper and Copper Alloys

NASA Astrophysics Data System (ADS)

Tschopp, M. A.; Murdoch, H. A.; Kecskes, L. J.; Darling, K. A.

2014-06-01

It is a new beginning for innovative fundamental and applied science in nanocrystalline materials. Many of the processing and consolidation challenges that have haunted nanocrystalline materials are now more fully understood, opening the doors for bulk nanocrystalline materials and parts to be produced. While challenges remain, recent advances in experimental, computational, and theoretical capability have allowed for bulk specimens that have heretofore been pursued only on a limited basis. This article discusses the methodology for synthesis and consolidation of bulk nanocrystalline materials using mechanical alloying, the alloy development and synthesis process for stabilizing these materials at elevated temperatures, and the physical and mechanical properties of nanocrystalline materials with a focus throughout on nanocrystalline copper and a nanocrystalline Cu-Ta system, consolidated via equal channel angular extrusion, with properties rivaling that of nanocrystalline pure Ta. Moreover, modeling and simulation approaches as well as experimental results for grain growth, grain boundary processes, and deformation mechanisms in nanocrystalline copper are briefly reviewed and discussed. Integrating experiments and computational materials science for synthesizing bulk nanocrystalline materials can bring about the next generation of ultrahigh strength materials for defense and energy applications.

Current Challenges in the First Principle Quantitative Modelling of the Lower Hybrid Current Drive in Tokamaks

NASA Astrophysics Data System (ADS)

Peysson, Y.; Bonoli, P. T.; Chen, J.; Garofalo, A.; Hillairet, J.; Li, M.; Qian, J.; Shiraiwa, S.; Decker, J.; Ding, B. J.; Ekedahl, A.; Goniche, M.; Zhai, X.

2017-10-01

The Lower Hybrid (LH) wave is widely used in existing tokamaks for tailoring current density profile or extending pulse duration to steady-state regimes. Its high efficiency makes it particularly attractive for a fusion reactor, leading to consider it for this purpose in ITER tokamak. Nevertheless, if basics of the LH wave in tokamak plasma are well known, quantitative modeling of experimental observations based on first principles remains a highly challenging exercise, despite considerable numerical efforts achieved so far. In this context, a rigorous methodology must be carried out in the simulations to identify the minimum number of physical mechanisms that must be considered to reproduce experimental shot to shot observations and also scalings (density, power spectrum). Based on recent simulations carried out for EAST, Alcator C-Mod and Tore Supra tokamaks, the state of the art in LH modeling is reviewed. The capability of fast electron bremsstrahlung, internal inductance li and LH driven current at zero loop voltage to constrain all together LH simulations is discussed, as well as the needs of further improvements (diagnostics, codes, LH model), for robust interpretative and predictive simulations.

Implications of pleiotropy: challenges and opportunities for mining Big Data in biomedicine.

PubMed

Yang, Can; Li, Cong; Wang, Qian; Chung, Dongjun; Zhao, Hongyu

2015-01-01

Pleiotropy arises when a locus influences multiple traits. Rich GWAS findings of various traits in the past decade reveal many examples of this phenomenon, suggesting the wide existence of pleiotropic effects. What underlies this phenomenon is the biological connection among seemingly unrelated traits/diseases. Characterizing the molecular mechanisms of pleiotropy not only helps to explain the relationship between diseases, but may also contribute to novel insights concerning the pathological mechanism of each specific disease, leading to better disease prevention, diagnosis and treatment. However, most pleiotropic effects remain elusive because their functional roles have not been systematically examined. A systematic investigation requires availability of qualified measurements at multilayered biological processes (e.g., transcription and translation). The rise of Big Data in biomedicine, such as high-quality multi-omics data, biomedical imaging data and electronic medical records of patients, offers us an unprecedented opportunity to investigate pleiotropy. There will be a great need of computationally efficient and statistically rigorous methods for integrative analysis of these Big Data in biomedicine. In this review, we outline many opportunities and challenges in methodology developments for systematic analysis of pleiotropy, and highlight its implications on disease prevention, diagnosis and treatment.

Stakeholder engagement in policy development: challenges and opportunities for human genomics

PubMed Central

Lemke, Amy A.; Harris-Wai, Julie N.

2015-01-01

Along with rapid advances in human genomics, policies governing genomic data and clinical technologies have proliferated. Stakeholder engagement is widely lauded as an important methodology for improving clinical, scientific, and public health policy decision making. The purpose of this paper is to examine how stakeholder engagement is used to develop policies in genomics research and public health areas, as well as to identify future priorities for conducting evidence-based stakeholder engagements. We focus on exemplars in biobanking and newborn screening to illustrate a variety of current stakeholder engagement in policy-making efforts. Each setting provides an important context for examining the methods of obtaining and integrating informed stakeholder voices into the policy-making process. While many organizations have an interest in engaging stakeholders with regard to genomic policy issues, there is broad divergence with respect to the stakeholders involved, the purpose of engagements, when stakeholders are engaged during policy development, methods of engagement, and the outcomes reported. Stakeholder engagement in genomics policy development is still at a nascent stage. Several challenges of using stakeholder engagement as a tool for genomics policy development remain, and little evidence regarding how to best incorporate stakeholder feedback into policy-making processes is currently available. PMID:25764215

Stakeholder engagement in policy development: challenges and opportunities for human genomics.

PubMed

Lemke, Amy A; Harris-Wai, Julie N

2015-12-01

Along with rapid advances in human genomics, policies governing genomic data and clinical technologies have proliferated. Stakeholder engagement is widely lauded as an important methodology for improving clinical, scientific, and public health policy decision making. The purpose of this paper is to examine how stakeholder engagement is used to develop policies in genomics research and public health areas, as well as to identify future priorities for conducting evidence-based stakeholder engagements. We focus on exemplars in biobanking and newborn screening to illustrate a variety of current stakeholder engagement in policy-making efforts. Each setting provides an important context for examining the methods of obtaining and integrating informed stakeholder voices into the policy-making process. While many organizations have an interest in engaging stakeholders with regard to genomic policy issues, there is broad divergence with respect to the stakeholders involved, the purpose of engagements, when stakeholders are engaged during policy development, methods of engagement, and the outcomes reported. Stakeholder engagement in genomics policy development is still at a nascent stage. Several challenges of using stakeholder engagement as a tool for genomics policy development remain, and little evidence regarding how to best incorporate stakeholder feedback into policy-making processes is currently available.

The Johns Hopkins Hospital: identifying and addressing risks and safety issues.

PubMed

Paine, Lori A; Baker, David R; Rosenstein, Beryl; Pronovost, Peter J

2004-10-01

At The Johns Hopkins Hospital (JHH), a culture of safety refers to the presence of characteristics such as the belief that harm is untenable and the use of a systems approach to analyzing safety issues. The leadership of JHH provides strategic planning guidance for safety and improvement initiatives, involves the patient safety committee in capital investment allocation decisions and in designing and planning new hospital facilities, and ensures that safety and quality head the agenda of board-of-trustees meetings. Although JHH takes a systems approach, structures such as monitoring staff behavior trends are used to hold people accountable for job performance. JHH encountered three major hurdles in implementing and sustaining a culture of safety. First, JHH's decentralized organizational structure contributes to a silo effect that limits the spread of ideas, practices, and culture. JHH intends to create an internal collaborative of departmental safety initiatives to foster opportunities for units to share ideas and results. Second, in response to the challenge of encouraging teams to think and act in an interdisciplinary fashion, communication and teamwork training are being used to enhance the effectiveness of interdisciplinary teams. Further development of valid and meaningful safety-related measurement and data collection methodologies is JHH's largest remaining challenge.

Culture’s building blocks: investigating cultural evolution in a LEGO construction task

PubMed Central

McGraw, John J.; Wallot, Sebastian; Mitkidis, Panagiotis; Roepstorff, Andreas

2014-01-01

One of the most essential but theoretically vexing issues regarding the notion of culture is that of cultural evolution and transmission: how a group’s accumulated solutions to invariant challenges develop and persevere over time. But at the moment, the notion of applying evolutionary theory to culture remains little more than a suggestive trope. Whereas the modern synthesis of evolutionary theory has provided an encompassing scientific framework for the selection and transmission of biological adaptations, a convincing theory of cultural evolution has yet to emerge. One of the greatest challenges for theorists is identifying the appropriate time scales and units of analysis in order to reduce the intractably large and complex phenomenon of “culture” into its component “building blocks.” In this paper, we present a model for scientifically investigating cultural processes by analyzing the ways people develop conventions in a series of LEGO construction tasks. The data revealed a surprising pattern in the selection of building bricks as well as features of car design across consecutive building sessions. Our findings support a novel methodology for studying the development and transmission of culture through the microcosm of interactive LEGO design and assembly. PMID:25309482

Culture's building blocks: investigating cultural evolution in a LEGO construction task.

PubMed

McGraw, John J; Wallot, Sebastian; Mitkidis, Panagiotis; Roepstorff, Andreas

2014-01-01

ONE OF THE MOST ESSENTIAL BUT THEORETICALLY VEXING ISSUES REGARDING THE NOTION OF CULTURE IS THAT OF CULTURAL EVOLUTION AND TRANSMISSION: how a group's accumulated solutions to invariant challenges develop and persevere over time. But at the moment, the notion of applying evolutionary theory to culture remains little more than a suggestive trope. Whereas the modern synthesis of evolutionary theory has provided an encompassing scientific framework for the selection and transmission of biological adaptations, a convincing theory of cultural evolution has yet to emerge. One of the greatest challenges for theorists is identifying the appropriate time scales and units of analysis in order to reduce the intractably large and complex phenomenon of "culture" into its component "building blocks." In this paper, we present a model for scientifically investigating cultural processes by analyzing the ways people develop conventions in a series of LEGO construction tasks. The data revealed a surprising pattern in the selection of building bricks as well as features of car design across consecutive building sessions. Our findings support a novel methodology for studying the development and transmission of culture through the microcosm of interactive LEGO design and assembly.

State of the art discovery with tumor profiling in pediatric oncology.

PubMed

Carroll, William L; Raetz, Elizabeth; Meyer, Julia

2015-01-01

It is an exciting era in pediatric oncology with the advent of new technologies to comprehensively characterize cancer genomes in childhood tumors. Defining the genetic landscape of pediatric tumors has not only provided critical insight into tumor evolution, but it has also offered promise for more effective treatment in some cases, such as Philadelphia chromosome-positive acute lymphoblastic leukemia (ALL) and anaplastic lymphoma kinase (ALK)-mutated tumors. However, several challenges remain as the field of genomic tumor profiling emerges. This new technology is costly, and the overall impact on survival has yet to be determined. Tumor heterogeneity and clonal evolution have also presented challenges in the development of targeted therapy. In this article, we review breakthroughs in gene sequencing methodology and discuss examples where genomic discoveries have resulted in the recognition of tumor susceptibility as well as incorporation of targeted therapy. We also discuss how broad scale comprehensive tumor analyses have demonstrated the convergence of individual genetic alterations on common relevant pathways. Although the impact of tumor profiling is best studied within the context of rigorously designed clinical trials, there is promise that there will be growing opportunities for the adaption of precision medicine in pediatric oncology in the future.

Estimates of Dietary Sodium Consumption in Patients With Chronic Heart Failure.

PubMed

Colin-Ramirez, Eloisa; Arcand, JoAnne; Ezekowitz, Justin A

2015-12-01

Estimating dietary sodium intake is a key component of dietary assessment in the clinical setting of HF to effectively implement appropriate dietary interventions for sodium reduction and monitor adherence to the dietary treatment. In a research setting, assessment of sodium intake is crucial to an essential methodology to evaluate outcomes after a dietary or behavioral intervention. Current available sodium intake assessment methods include 24-hour urine collection, spot urine collections, multiple day food records, food recalls, and food frequency questionnaires. However, these methods have inherent limitations that make assessment of sodium intake challenging, and the utility of traditional methods may be questionable for estimating sodium intake in patients with HF. Thus, there are remaining questions about how to best assess dietary sodium intake in this patient population, and there is a need to identify a reliable method to assess and monitor sodium intake in the research and clinical setting of HF. This paper provides a comprehensive review of the current methods for sodium intake assessment, addresses the challenges for its accurate evaluation, and highlights the relevance of applying the highest-quality measurement methods in the research setting to minimize the risk of biased data. Copyright © 2015 Elsevier Inc. All rights reserved.

Microbial Efflux Systems and Inhibitors: Approaches to Drug Discovery and the Challenge of Clinical Implementation

PubMed Central

Kourtesi, Christina; Ball, Anthony R; Huang, Ying-Ying; Jachak, Sanjay M; Vera, D Mariano A; Khondkar, Proma; Gibbons, Simon; Hamblin, Michael R; Tegos, George P

2013-01-01

Conventional antimicrobials are increasingly ineffective due to the emergence of multidrug-resistance among pathogenic microorganisms. The need to overcome these deficiencies has triggered exploration for novel and unconventional approaches to controlling microbial infections. Multidrug efflux systems (MES) have been a profound obstacle in the successful deployment of antimicrobials. The discovery of small molecule efflux system blockers has been an active and rapidly expanding research discipline. A major theme in this platform involves efflux pump inhibitors (EPIs) from natural sources. The discovery methodologies and the available number of natural EPI-chemotypes are increasing. Advances in our understanding of microbial physiology have shed light on a series of pathways and phenotypes where the role of efflux systems is pivotal. Complementing existing antimicrobial discovery platforms such as photodynamic therapy (PDT) with efflux inhibition is a subject under investigation. This core information is a stepping stone in the challenge of highlighting an effective drug development path for EPIs since the puzzle of clinical implementation remains unsolved. This review summarizes advances in the path of EPI discovery, discusses potential avenues of EPI implementation and development, and underlines the need for highly informative and comprehensive translational approaches. PMID:23569468

Psychophysiological Assessment in Pilots Performing Challenging Simulated and Real Flight Maneuvers.

PubMed

Johannes, Bernd; Rothe, Stefanie; Gens, André; Westphal, Soeren; Birkenfeld, Katja; Mulder, Edwin; Rittweger, Jörn; Ledderhos, Carla

2017-09-01

The objective assessment of psychophysiological arousal during challenging flight maneuvers is of great interest to aerospace medicine, but remains a challenging task. In the study presented here, a vector-methodological approach was used which integrates different psychophysiological variables, yielding an integral arousal index called the Psychophysiological Arousal Value (PAV). The arousal levels of 15 male pilots were assessed during predetermined, well-defined flight maneuvers performed under simulated and real flight conditions. The physiological data, as expected, revealed inter- and intra-individual differences for the various measurement conditions. As indicated by the PAV, air-to-air refueling (AAR) turned out to be the most challenging task. In general, arousal levels were comparable between simulator and real flight conditions. However, a distinct difference was observed when the pilots were divided by instructors into two groups based on their proficiency in AAR with AWACS (AAR-Novices vs. AAR-Professionals). AAR-Novices had on average more than 2000 flight hours on other aircrafts. They showed higher arousal reactions to AAR in real flight (contact: PAV score 8.4 ± 0.37) than under simulator conditions (7.1 ± 0.30), whereas AAR-Professionals did not (8.5 ± 0.46 vs. 8.8 ± 0.80). The psychophysiological arousal value assessment was tested in field measurements, yielding quantifiable arousal differences between proficiency groups of pilots during simulated and real flight conditions. The method used in this study allows an evaluation of the psychophysiological cost during a certain flying performance and thus is possibly a valuable tool for objectively evaluating the actual skill status of pilots.Johannes B, Rothe S, Gens A, Westphal S, Birkenfeld K, Mulder E, Rittweger J, Ledderhos C. Psychophysiological assessment in pilots performing challenging simulated and real flight maneuvers. Aerosp Med Hum Perform. 2017; 88(9):834-840.

Enrolling African-American and Latino patients with asthma in comparative effectiveness research: Lessons learned from 8 patient-centered studies.

PubMed

Kramer, C Bradley; LeRoy, Lisa; Donahue, Sara; Apter, Andrea J; Bryant-Stephens, Tyra; Elder, John P; Hamilton, Winifred J; Krishnan, Jerry A; Shelef, Deborah Q; Stout, James W; Sumino, Kaharu; Teach, Stephen J; Federman, Alex D

2016-12-01

African-American and Latino patients are often difficult to recruit for asthma studies. This challenge is a barrier to improving asthma care and outcomes for these populations. We sought to examine the recruitment experiences of 8 asthma comparative effectiveness studies that specifically targeted African-American and Latino patients, and identify the solutions they developed to improve recruitment. Case report methodology was used to gather and evaluate information on study design, recruitment procedures and outcomes from study protocols and annual reports, and in-depth interviews with each research team. Data were analyzed for themes, commonalities, and differences. There were 4 domains of recruitment challenges: individual participant, institutional, research team, and study intervention. Participants had competing demands for time and some did not believe they had asthma. Institutional challenges included organizational policies governing monetary incentives and staff hiring. Research team challenges included ongoing training needs of recruitment staff, and intervention designs often were unappealing to participants because of inconveniences. Teams identified a host of strategies to address these challenges, most importantly engagement of patients and other stakeholders in study design and troubleshooting, and flexibility in data collection and intervention application to meet the varied needs of patients. Asthma researchers may have greater success with recruitment by addressing uncertainty among patients about asthma diagnosis, engaging stakeholders in all aspects of study design and implementation, and maximizing flexibility of study and intervention protocols. However, even with such efforts, engagement of African-American and Latino patients in asthma research may remain low. Greater investment in research on engaging these populations in asthma research may ultimately be needed to improve their asthma care and outcomes. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Measuring alterations in oscillatory brain networks in schizophrenia with resting-state MEG: State-of-the-art and methodological challenges.

PubMed

Alamian, Golnoush; Hincapié, Ana-Sofía; Pascarella, Annalisa; Thiery, Thomas; Combrisson, Etienne; Saive, Anne-Lise; Martel, Véronique; Althukov, Dmitrii; Haesebaert, Frédéric; Jerbi, Karim

2017-09-01

Neuroimaging studies provide evidence of disturbed resting-state brain networks in Schizophrenia (SZ). However, untangling the neuronal mechanisms that subserve these baseline alterations requires measurement of their electrophysiological underpinnings. This systematic review specifically investigates the contributions of resting-state Magnetoencephalography (MEG) in elucidating abnormal neural organization in SZ patients. A systematic literature review of resting-state MEG studies in SZ was conducted. This literature is discussed in relation to findings from resting-state fMRI and EEG, as well as to task-based MEG research in SZ population. Importantly, methodological limitations are considered and recommendations to overcome current limitations are proposed. Resting-state MEG literature in SZ points towards altered local and long-range oscillatory network dynamics in various frequency bands. Critical methodological challenges with respect to experiment design, and data collection and analysis need to be taken into consideration. Spontaneous MEG data show that local and global neural organization is altered in SZ patients. MEG is a highly promising tool to fill in knowledge gaps about the neurophysiology of SZ. However, to reach its fullest potential, basic methodological challenges need to be overcome. MEG-based resting-state power and connectivity findings could be great assets to clinical and translational research in psychiatry, and SZ in particular. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

Assessing Brain–Muscle Connectivity in Human Locomotion through Mobile Brain/Body Imaging: Opportunities, Pitfalls, and Future Directions

PubMed Central

Gennaro, Federico; de Bruin, Eling D.

2018-01-01

Assessment of the cortical role during bipedalism has been a methodological challenge. While surface electroencephalography (EEG) is capable of non-invasively measuring cortical activity during human locomotion, it is associated with movement artifacts obscuring cerebral sources of activity. Recently, statistical methods based on blind source separation revealed potential for resolving this issue, by segregating non-cerebral/artifactual from cerebral sources of activity. This step marked a new opportunity for the investigation of the brains’ role while moving and was tagged mobile brain/body imaging (MoBI). This methodology involves simultaneous mobile recording of brain activity with several other body behavioral variables (e.g., muscle activity and kinematics), through wireless recording wearable devices/sensors. Notably, several MoBI studies using EEG–EMG approaches recently showed that the brain is functionally connected to the muscles and active throughout the whole gait cycle and, thus, rejecting the long-lasting idea of a solely spinal-driven bipedalism. However, MoBI and brain/muscle connectivity assessments during human locomotion are still in their fledgling state of investigation. Mobile brain/body imaging approaches hint toward promising opportunities; however, there are some remaining pitfalls that need to be resolved before considering their routine clinical use. This article discusses several of these pitfalls and proposes research to address them. Examples relate to the validity, reliability, and reproducibility of this method in ecologically valid scenarios and in different populations. Furthermore, whether brain/muscle connectivity within the MoBI framework represents a potential biomarker in neuromuscular syndromes where gait disturbances are evident (e.g., age-related sarcopenia) remains to be determined. PMID:29535995

Qualitative Approaches to Research in Counselling and Psychotherapy: Issues and Challenges.

ERIC Educational Resources Information Center

McLeod, John

1996-01-01

Discusses key issues which address the distinctive dilemmas and challenges associated with qualitative approaches to evaluating counseling. Investigates such concerns as relationships with research participants, ethics, reflexivity, methodological choice, communicability, perspective, and obviousness. Makes some suggestions regarding the link…

Probing heterotrimeric G protein activation: applications to biased ligands

PubMed Central

Denis, Colette; Saulière, Aude; Galandrin, Ségolène; Sénard, Jean-Michel; Galés, Céline

2012-01-01

Cell surface G protein-coupled receptors (GPCRs) drive numerous signaling pathways involved in the regulation of a broad range of physiologic processes. Today, they represent the largest target for modern drugs development with potential application in all clinical fields. Recently, the concept of “ligand-directed trafficking” has led to a conceptual revolution in pharmacological theory, thus opening new avenues for drug discovery. Accordingly, GPCRs do not function as simple on-off switch but rather as filters capable of selecting activation of specific signals and thus generating textured responses to ligands, a phenomenon often referred to as ligand-biased signaling. Also, one challenging task today remains optimization of pharmacological assays with increased sensitivity so to better appreciate the inherent texture of ligand responses. However, considering that a single receptor has pleiotropic signalling properties and that each signal can crosstalk at different levels, biased activity remains thus difficult to evaluate. One strategy to overcome these limitations would be examining the initial steps following receptor activation. Even if some G protein-independent functions have been recently described, heterotrimeric G protein activation remains a general hallmark for all GPCRs families and the first cellular event subsequent to agonist binding to the receptor. Herein, we review the different methodologies classically used or recently developed to monitor G protein activation and discuss them in the context of G protein biased -ligands. PMID:22229559

Increasing sustainable stormwater management adaption through transdisciplinary research

NASA Astrophysics Data System (ADS)

Wingfield, Thea; Potter, Karen; Jones, Gareth; Spees, Jack; Macdonald, Neil

2016-04-01

The Ribble Rivers Trust leads a partnership of land and water management organisations that use a holistic approach to water management in the Ribble catchment. They are interested in incorporating sustainable stormwater systems, into their program of delivery with a view to ensuring that their activities to improve the environments and habitats of the catchment also contribute to reducing flood risk. A methodology, to locate interventions that would slow water within the catchment are identified; however partner buy in, institutional caution and economic barriers are felt to be hindering delivery. In response a transdisciplinary research project in which both the academics of the University of Liverpool and the practitioners of The Ribble Rivers Trust are active investigators has been established. The project aims to increase the uptake of sustainable stormwater management techniques through the analysis of the institutional, experiential and governance processes and their interactions with the physical hydrological processes governing stormwater systems. Research that is transdisciplinary must integrate academic knowledge with practitioner, local understanding and practice. Furthermore methodologies belonging to different academic fields must be blended together to collect, analyse and interpret data in order to examine complex problems through different disciplinary lenses in an integrated way. This approach has been developed in response to the complex relationships of cause and effect of contemporary inter-related economic, environmental and societal challenges. There have been a number of challenges to overcome as transdisciplinary researchers, the first and most important was to understand the different research philosophies and theoretical assumptions behind various natural science and social science research methods. Without this understanding research methodologies could be flawed and would not be effectively integrated and the data would not be interpreted correctly. In practice it has also been found that the roles of the research team cannot remain fixed. Researchers must be able to move between participant, observer, facilitator, campaigner, partner and decision maker depending on what is being studied and which methods are being used. The most effective way in which to accomplish these chameleon like transitions is to have a strong and secure framework of research questions that are always referred back to.

Challenges Faced by Pre-Service Chemistry Teachers Teaching in a Laboratory and Their Solution Proposals

ERIC Educational Resources Information Center

Yalcin-Celik, Ayse; Kadayifci, Hakki; Uner, Sinem; Turan-Oluk, Nurcan

2017-01-01

This study examines the challenges faced by pre-service chemistry teachers teaching in a laboratory and their proposed solutions to these challenges. The study was conducted in a 13-week-long methodology course. Written statements from participants and observations from researchers were used as data sources. From these data, it was found that the…

Methodological Challenges in Studies Comparing Prehospital Advanced Life Support with Basic Life Support.

PubMed

Li, Timmy; Jones, Courtney M C; Shah, Manish N; Cushman, Jeremy T; Jusko, Todd A

2017-08-01

Determining the most appropriate level of care for patients in the prehospital setting during medical emergencies is essential. A large body of literature suggests that, compared with Basic Life Support (BLS) care, Advanced Life Support (ALS) care is not associated with increased patient survival or decreased mortality. The purpose of this special report is to synthesize the literature to identify common study design and analytic challenges in research studies that examine the effect of ALS, compared to BLS, on patient outcomes. The challenges discussed in this report include: (1) choice of outcome measure; (2) logistic regression modeling of common outcomes; (3) baseline differences between study groups (confounding); (4) inappropriate statistical adjustment; and (5) inclusion of patients who are no longer at risk for the outcome. These challenges may affect the results of studies, and thus, conclusions of studies regarding the effect of level of prehospital care on patient outcomes should require cautious interpretation. Specific alternatives for avoiding these challenges are presented. Li T , Jones CMC , Shah MN , Cushman JT , Jusko TA . Methodological challenges in studies comparing prehospital Advanced Life Support with Basic Life Support. Prehosp Disaster Med. 2017;32(4):444-450.

Paleogenetic Analyses Reveal Unsuspected Phylogenetic Affinities between Mice and the Extinct Malpaisomys insularis, an Endemic Rodent of the Canaries

PubMed Central

Gros-Balthazard, Muriel; Hughes, Sandrine; Alcover, Josep Antoni; Hutterer, Rainer; Rando, Juan Carlos; Michaux, Jacques; Hänni, Catherine

2012-01-01

Background The lava mouse, Malpaisomys insularis, was endemic to the Eastern Canary islands and became extinct at the beginning of the 14th century when the Europeans reached the archipelago. Studies to determine Malpaisomys' phylogenetic affinities, based on morphological characters, remained inconclusive because morphological changes experienced by this insular rodent make phylogenetic investigations a real challenge. Over 20 years since its first description, Malpaisomys' phylogenetic position remains enigmatic. Methodology/Principal Findings In this study, we resolved this issue using molecular characters. Mitochondrial and nuclear markers were successfully amplified from subfossils of three lava mouse samples. Molecular phylogenetic reconstructions revealed, without any ambiguity, unsuspected relationships between Malpaisomys and extant mice (genus Mus, Murinae). Moreover, through molecular dating we estimated the origin of the Malpaisomys/mouse clade at 6.9 Ma, corresponding to the maximal age at which the archipelago was colonised by the Malpaisomys ancestor via natural rafting. Conclusion/Significance This study reconsiders the derived morphological characters of Malpaisomys in light of this unexpected molecular finding. To reconcile molecular and morphological data, we propose to consider Malpaisomys insularis as an insular lineage of mouse. PMID:22363563

Discrimination and health inequities.

PubMed

Krieger, Nancy

2014-01-01

In 1999, only 20 studies in the public health literature employed instruments to measure self-reported experiences of discrimination. Fifteen years later, the number of empirical investigations on discrimination and health easily exceeds 500, with these studies increasingly global in scope and focused on major types of discrimination variously involving race/ethnicity, indigenous status, immigrant status, gender, sexuality, disability, and age, separately and in combination. And yet, as I also document, even as the number of investigations has dramatically expanded, the scope remains narrow: studies remain focused primarily on interpersonal discrimination, and scant research investigates the health impacts of structural discrimination, a gap consonant with the limited epidemiologic research on political systems and population health. Accordingly, to help advance the state of the field, this updated review article: (a) briefly reviews definitions of discrimination, illustrated with examples from the United States; (b) discusses theoretical insights useful for conceptualizing how discrimination can become embodied and produce health inequities, including via distortion of scientific knowledge; (c) concisely summarizes extant evidence--both robust and inconsistent--linking discrimination and health; and (d) addresses several key methodological controversies and challenges, including the need for careful attention to domains, pathways, level, and spatiotemporal scale, in historical context.

Investigating the underlying mechanisms of aberrant behaviors in bipolar disorder from patients to models

PubMed Central

van Enkhuizen, Jordy; Geyer, Mark A.; Minassian, Arpi; Perry, William; Henry, Brook L.; Young, Jared W.

2015-01-01

Psychiatric patients with bipolar disorder suffer from states of depression and mania, during which a variety of symptoms are present. Current treatments are limited and neurocognitive deficits in particular often remain untreated. Targeted therapies based on the biological mechanisms of bipolar disorder could fill this gap and benefit patients and their families. Developing targeted therapies would benefit from appropriate animal models which are challenging to establish, but remain a vital tool. In this review, we summarize approaches to create a valid model relevant to bipolar disorder. We focus on studies that use translational tests of multivariate exploratory behavior, sensorimotor gating, decision-making under risk, and attentional functioning to discover profiles that are consistent between patients and rodent models. Using this battery of translational tests, similar behavior profiles in bipolar mania patients and mice with reduced dopamine transporter activity have been identified. Future investigations should combine other animal models that are biologically relevant to the neuropsychiatric disorder with translational behavioral assessment as outlined here. This methodology can be utilized to develop novel targeted therapies that relieve symptoms for more patients without common side effects caused by current treatments. PMID:26297513

Shotgun protein sequencing: assembly of peptide tandem mass spectra from mixtures of modified proteins.

PubMed

Bandeira, Nuno; Clauser, Karl R; Pevzner, Pavel A

2007-07-01

Despite significant advances in the identification of known proteins, the analysis of unknown proteins by MS/MS still remains a challenging open problem. Although Klaus Biemann recognized the potential of MS/MS for sequencing of unknown proteins in the 1980s, low throughput Edman degradation followed by cloning still remains the main method to sequence unknown proteins. The automated interpretation of MS/MS spectra has been limited by a focus on individual spectra and has not capitalized on the information contained in spectra of overlapping peptides. Indeed the powerful shotgun DNA sequencing strategies have not been extended to automated protein sequencing. We demonstrate, for the first time, the feasibility of automated shotgun protein sequencing of protein mixtures by utilizing MS/MS spectra of overlapping and possibly modified peptides generated via multiple proteases of different specificities. We validate this approach by generating highly accurate de novo reconstructions of multiple regions of various proteins in western diamondback rattlesnake venom. We further argue that shotgun protein sequencing has the potential to overcome the limitations of current protein sequencing approaches and thus catalyze the otherwise impractical applications of proteomics methodologies in studies of unknown proteins.

Methodological issues in oral health research: intervention studies.

PubMed

O'Mullane, Denis; James, Patrice; Whelton, Helen; Parnell, Carmel

2012-02-01

To provide a broad overview of methodological issues in the design and evaluation of intervention studies in dental public health, with particular emphasis on explanatory trials, pragmatic trials and complex interventions. We present a narrative summary of selected publications from the literature outlining both historical and recent challenges in the design and evaluation of intervention studies and describe some recent tools that may help researchers to address these challenges. It is now recognised that few intervention studies in dental public health are purely explanatory or pragmatic. We describe the PRECIS tool which can be used by trialists to assess and display the position of their trial on a continuum between the extremes of explanatory and pragmatic trials. The tool aims to help trialists make design decisions that are in line with their stated aims. The increasingly complex nature of dental public health interventions presents particular design and evaluation challenges. The revised Medical Research Council (MRC) guidance for the development and evaluation of complex interventions which emphasises the importance of planning and process evaluation is a welcome development. We briefly describe the MRC guidance and outline some examples of complex interventions in the field of oral health. The role of observational studies in monitoring public health interventions when the conduct of RCTs is not appropriate or feasible is acknowledged. We describe the STROBE statement and outline the implications of the STROBE guidelines for dental public health. The methodological challenges in the design, conduct and reporting of intervention studies in oral health are considerable. The need to provide reliable evidence to support innovative new strategies in oral health policy is a major impetus in these fields. No doubt the 'Methodological Issues in Oral Health Research' group will have further opportunities to highlight this work. © 2012 John Wiley & Sons A/S.

Applications of Rapid Evaluation of Metapopulation Persistence (REMP) in Conservation Planning for Vulnerable Fauna Species.

PubMed

Taylor, Subhashni; Drielsma, Michael; Taylor, Robert; Kumar, Lalit

2016-06-01

In many regions species are declining due to fragmentation and loss of habitat. If species persistence is to be achieved, ecologically informed, effective conservation action is required. Yet it remains a challenge to identify optimal places in a landscape to direct habitat reconstruction and management. Rather than relying on individual landscape metrics, process-based regional scale assessment methodology is needed that focuses primarily on species persistence. This means integrating, according to species' ecology, habitat extent, suitability, quality and spatial configuration. The rapid evaluation of metapopulation persistence (REMP) methodology has been developed for this purpose. However, till now no practical conservation planning application of REMP has been described. By integration of expert ecological knowledge, we extended REMP's capabilities to prioritize conservation action for a highly modified agricultural region of central NSW, Australia based on the metapopulation ecology of 34 fauna species. The region's current capacity to support the species was evaluated in relation to the pre-European state for which there was known viability. Six of the species were found to currently have insufficient habitat to support viable populations. Seeking locations to maximize overall improvement in viability for these species, we prioritized conservation action to locations near the threshold of metapopulation persistence.

Spatio-Temporal Dimensions of Child Poverty in America, 1990-2010.

PubMed

Call, Maia A; Voss, Paul R

2016-01-01

The persistence of childhood poverty in the United States, a wealthy and developed country, continues to pose both an analytical dilemma and public policy challenge, despite many decades of research and remedial policy implementation. In this paper, our goals are twofold, though our primary focus is methodological. We attempt both to examine the relationship between space, time, and previously established factors correlated with childhood poverty at the county level in the continental United States as well as to provide an empirical case study to demonstrate an underutilized methodological approach. We analyze a spatially consistent dataset built from the 1990 and 2000 U.S. Censuses, and the 2006-2010 American Community Survey. Our analytic approach includes cross-sectional spatial models to estimate the reproduction of poverty for each of the reference years as well as a fixed effects panel data model, to analyze change in child poverty over time. In addition, we estimate a full space-time interaction model, which adjusts for spatial and temporal variation in these data. These models reinforce our understanding of the strong regional persistence of childhood poverty in the U.S. over time and suggest that the factors impacting childhood poverty remain much the same today as they have in past decades.

Greenhouse gases accounting and reporting for waste management--a South African perspective.

PubMed

Friedrich, Elena; Trois, Cristina

2010-11-01

This paper investigates how greenhouse gases are accounted and reported in the waste sector in South Africa. Developing countries (including South Africa) do not have binding emission reduction targets, but many of them publish different greenhouse gas emissions data which have been accounted and reported in different ways. Results show that for South Africa, inventories at national and municipal level are the most important tools in the process of accounting and reporting greenhouse gases from waste. For the development of these inventories international initiatives were important catalysts at national and municipal levels, and assisted in developing local expertise, resulting in increased output quality. However, discrepancies in the methodology used to account greenhouse gases from waste between inventories still remain a concern. This is a challenging issue for developing countries, especially African ones, since higher accuracy methods are more data intensive. Analysis of the South African inventories shows that results from the recent inventories can not be compared with older ones due to the use of different accounting methodologies. More recently the use of Clean Development Mechanism (CDM) procedures in Africa, geared towards direct measurements of greenhouse gases from landfill sites, has increased and resulted in an improvement of the quality of greenhouse gas inventories at municipal level. Copyright © 2010 Elsevier Ltd. All rights reserved.

Strategies to design clinical studies to identify predictive biomarkers in cancer research.

PubMed

Perez-Gracia, Jose Luis; Sanmamed, Miguel F; Bosch, Ana; Patiño-Garcia, Ana; Schalper, Kurt A; Segura, Victor; Bellmunt, Joaquim; Tabernero, Josep; Sweeney, Christopher J; Choueiri, Toni K; Martín, Miguel; Fusco, Juan Pablo; Rodriguez-Ruiz, Maria Esperanza; Calvo, Alfonso; Prior, Celia; Paz-Ares, Luis; Pio, Ruben; Gonzalez-Billalabeitia, Enrique; Gonzalez Hernandez, Alvaro; Páez, David; Piulats, Jose María; Gurpide, Alfonso; Andueza, Mapi; de Velasco, Guillermo; Pazo, Roberto; Grande, Enrique; Nicolas, Pilar; Abad-Santos, Francisco; Garcia-Donas, Jesus; Castellano, Daniel; Pajares, María J; Suarez, Cristina; Colomer, Ramon; Montuenga, Luis M; Melero, Ignacio

2017-02-01

The discovery of reliable biomarkers to predict efficacy and toxicity of anticancer drugs remains one of the key challenges in cancer research. Despite its relevance, no efficient study designs to identify promising candidate biomarkers have been established. This has led to the proliferation of a myriad of exploratory studies using dissimilar strategies, most of which fail to identify any promising targets and are seldom validated. The lack of a proper methodology also determines that many anti-cancer drugs are developed below their potential, due to failure to identify predictive biomarkers. While some drugs will be systematically administered to many patients who will not benefit from them, leading to unnecessary toxicities and costs, others will never reach registration due to our inability to identify the specific patient population in which they are active. Despite these drawbacks, a limited number of outstanding predictive biomarkers have been successfully identified and validated, and have changed the standard practice of oncology. In this manuscript, a multidisciplinary panel reviews how those key biomarkers were identified and, based on those experiences, proposes a methodological framework-the DESIGN guidelines-to standardize the clinical design of biomarker identification studies and to develop future research in this pivotal field. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Workflows and performances in the ranking prediction of 2016 D3R Grand Challenge 2: lessons learned from a collaborative effort.

PubMed

Gao, Ying-Duo; Hu, Yuan; Crespo, Alejandro; Wang, Deping; Armacost, Kira A; Fells, James I; Fradera, Xavier; Wang, Hongwu; Wang, Huijun; Sherborne, Brad; Verras, Andreas; Peng, Zhengwei

2018-01-01

The 2016 D3R Grand Challenge 2 includes both pose and affinity or ranking predictions. This article is focused exclusively on affinity predictions submitted to the D3R challenge from a collaborative effort of the modeling and informatics group. Our submissions include ranking of 102 ligands covering 4 different chemotypes against the FXR ligand binding domain structure, and the relative binding affinity predictions of the two designated free energy subsets of 15 and 18 compounds. Using all the complex structures prepared in the same way allowed us to cover many types of workflows and compare their performances effectively. We evaluated typical workflows used in our daily structure-based design modeling support, which include docking scores, force field-based scores, QM/MM, MMGBSA, MD-MMGBSA, and MacroModel interaction energy estimations. The best performing methods for the two free energy subsets are discussed. Our results suggest that affinity ranking still remains very challenging; that the knowledge of more structural information does not necessarily yield more accurate predictions; and that visual inspection and human intervention are considerably important for ranking. Knowledge of the mode of action and protein flexibility along with visualization tools that depict polar and hydrophobic maps are very useful for visual inspection. QM/MM-based workflows were found to be powerful in affinity ranking and are encouraged to be applied more often. The standardized input and output enable systematic analysis and support methodology development and improvement for high level blinded predictions.

Workflows and performances in the ranking prediction of 2016 D3R Grand Challenge 2: lessons learned from a collaborative effort

NASA Astrophysics Data System (ADS)

Gao, Ying-Duo; Hu, Yuan; Crespo, Alejandro; Wang, Deping; Armacost, Kira A.; Fells, James I.; Fradera, Xavier; Wang, Hongwu; Wang, Huijun; Sherborne, Brad; Verras, Andreas; Peng, Zhengwei

2018-01-01

The 2016 D3R Grand Challenge 2 includes both pose and affinity or ranking predictions. This article is focused exclusively on affinity predictions submitted to the D3R challenge from a collaborative effort of the modeling and informatics group. Our submissions include ranking of 102 ligands covering 4 different chemotypes against the FXR ligand binding domain structure, and the relative binding affinity predictions of the two designated free energy subsets of 15 and 18 compounds. Using all the complex structures prepared in the same way allowed us to cover many types of workflows and compare their performances effectively. We evaluated typical workflows used in our daily structure-based design modeling support, which include docking scores, force field-based scores, QM/MM, MMGBSA, MD-MMGBSA, and MacroModel interaction energy estimations. The best performing methods for the two free energy subsets are discussed. Our results suggest that affinity ranking still remains very challenging; that the knowledge of more structural information does not necessarily yield more accurate predictions; and that visual inspection and human intervention are considerably important for ranking. Knowledge of the mode of action and protein flexibility along with visualization tools that depict polar and hydrophobic maps are very useful for visual inspection. QM/MM-based workflows were found to be powerful in affinity ranking and are encouraged to be applied more often. The standardized input and output enable systematic analysis and support methodology development and improvement for high level blinded predictions.

Central thalamic deep brain stimulation to promote recovery from chronic posttraumatic minimally conscious state: challenges and opportunities.

PubMed

Giacino, Joseph; Fins, Joseph J; Machado, Andre; Schiff, Nicholas D

2012-07-01

Central thalamic deep brain stimulation (CT-DBS) may have therapeutic potential to improve behavioral functioning in patients with severe traumatic brain injury (TBI), but its use remains experimental. Current research suggests that the central thalamus plays a critical role in modulating arousal during tasks requiring sustained attention, working memory, and motor function. The aim of the current article is to review the methodology used in the CT-DBS protocol developed by our group, outline the challenges we encountered and offer suggestions for future DBS trials in this population. RATIONAL FOR CT-DBS IN TBI:  CT-DBS may therefore be able to stimulate these functions by eliciting action potentials that excite thalamocortical and thalamostriatal pathways. Because patients in chronic minimally conscious state (MCS) have a very low probability of regaining functional independence, yet often have significant sparing of cortical connectivity, they may represent a particularly appropriate target group for CT-DBS. PIlOT STUDY RESULTS:  We have conducted a series of single-subject studies of CT-DBS in patients with chronic posttraumatic MCS, with 24-month follow-up. Outcomes were measured using the Coma Recovery Scale-Revised as well as a battery of secondary outcome measures to capture more granular changes. Findings from our index case suggest that CT-DBS can significantly increase functional communication, motor performance, feeding, and object naming in the DBS on state, with performance in some domains remaining above baseline even after DBS was turned off. The use of CT-DBS in patients in MCS, however, presents challenges at almost every step, including during surgical planning, outcome measurement, and postoperative care. Additionally, given the difficulties of obtaining informed consent from patients in MCS and the experimental nature of the treatment, a robust, scientifically rooted ethical framework is resented for pursuing this line of work. © 2012 International Neuromodulation Society.

Critical Pedagogy and APA: A Resonant (and Timely) Interdisciplinary Blend.

PubMed

Connolly, Maureen; Harvey, William J

2018-04-12

Critical pedagogy owes much of its emergence, development, and ongoing relevance to the work of Paulo Freire whose legacy remains relevant for a next generation of scholars who seek to explore issues of inclusion, oppression, social justice, and authentic expression. An interdisciplinary dialogue between critical pedagogy and adapted physical activity is timely, appropriate, and should focus on complex profiles of neurodiversity, mental illness, and mental health, with emphasis on pedagogic practices of practitioners in service delivery and teacher educators who prepare them for professional practice. A case-based scenario approach is used to present practitioner and teacher educator practices. Concrete examples are provided for analyzing and understanding deeper issues and challenges related to neurodiversity in a variety of embodied dimensions in educational and activity contexts. We work with Szostak's approach to interdisciplinary research and model an analysis strategy that integrates and applies the methodological features of interdisciplinarity, adapted physical activity, and critical pedagogy.

Decarboxylative alkylation for site-selective bioconjugation of native proteins via oxidation potentials.

PubMed

Bloom, Steven; Liu, Chun; Kölmel, Dominik K; Qiao, Jennifer X; Zhang, Yong; Poss, Michael A; Ewing, William R; MacMillan, David W C

2018-02-01

The advent of antibody-drug conjugates as pharmaceuticals has fuelled a need for reliable methods of site-selective protein modification that furnish homogeneous adducts. Although bioorthogonal methods that use engineered amino acids often provide an elegant solution to the question of selective functionalization, achieving homogeneity using native amino acids remains a challenge. Here, we explore visible-light-mediated single-electron transfer as a mechanism towards enabling site- and chemoselective bioconjugation. Specifically, we demonstrate the use of photoredox catalysis as a platform to selectivity wherein the discrepancy in oxidation potentials between internal versus C-terminal carboxylates can be exploited towards obtaining C-terminal functionalization exclusively. This oxidation potential-gated technology is amenable to endogenous peptides and has been successfully demonstrated on the protein insulin. As a fundamentally new approach to bioconjugation this methodology provides a blueprint toward the development of photoredox catalysis as a generic platform to target other redox-active side chains for native conjugation.

Solution Exchange Lithography: A Versatile Tool for Sequential Surface Engineering

NASA Astrophysics Data System (ADS)

Pester, Christian; Mattson, Kaila; Bothman, David; Klinger, Daniel; Lee, Kenneth; Discekici, Emre; Narupai, Benjaporn; Hawker, Craig

The covalent attachment of polymers has emerged as a viable strategy for the preparation of multi-functional surfaces. Patterned, surface-grafted polymer brushes provide spatial control over wetting, mechanical, biological or electronic properties, and allow fabrication of `intelligent' substrates which selectively adapt to their environment. However, the route towards patterned polymer brush surfaces often remains challenging, creating a demand for more efficient and less complicated fabrication strategies. We describe the design and application of a novel experimental setup to combine light-mediated and flow chemistry for the fabrication of hierarchical surface-grafted polymer brushes. Using light-mediated, surface initiated controlled radical polymerization and post-functionalization via well-established, and highly efficient chemistries, polymer brush films of previously unimaginable complexity are now shown to be accessible. This methodology allows full flexibility to exchange both lithographic photomasks and chemical environments in-situ, readily affording multidimensional thin film architectures, all from uniformly functionalized substrates.

Nurse manager perceptions of role satisfaction and retention at an academic medical center.

PubMed

Zwink, Jennifer E; Dzialo, Maureen; Fink, Regina M; Oman, Kathleen S; Shiskowsky, Kaycee; Waite, Kathi; DeVine, Deborah; Sanders, Carolyn L; Le-Lazar, Jamie T T

2013-03-01

The aim of this study was to explore the perceptions of inpatient acute care nurse managers (NM) employed at an academic Magnet® hospital about factors that influence NM retention, including current work environment, satisfaction, work-life balance, sucssful NM traits, and personal development and educational needs. Nurse managers are challenged with increased workloads impacting their ability to implement all role components. A qualitative descriptive study design used focus group methodology to explore perceptions of the NM role. Nurse managers identified staff recognition, support, peer relationships, collaboration, and ability to make positive change as factors influencing their decision to remain in the role. Burnout factors included workload issues, work-life imbalance, and difficulty sustaining positive relationships. Traits supporting success were communication, resiliency, integrity, and a visionary outlook. Suggestions for NM development and education were identified. Findings can be used to improve NM satisfaction, work-life balance, recruitment, retention, and succession planning.

Advances in the Fabrication of Antimicrobial Hydrogels for Biomedical Applications.

PubMed

González-Henríquez, Carmen M; Sarabia-Vallejos, Mauricio A; Rodriguez-Hernandez, Juan

2017-02-26

This review describes, in an organized manner, the recent developments in the elaboration of hydrogels that possess antimicrobial activity. The fabrication of antibacterial hydrogels for biomedical applications that permits cell adhesion and proliferation still remains as an interesting challenge, in particular for tissue engineering applications. In this context, a large number of studies has been carried out in the design of hydrogels that serve as support for antimicrobial agents (nanoparticles, antibiotics, etc.). Another interesting approach is to use polymers with inherent antimicrobial activity provided by functional groups contained in their structures, such as quaternary ammonium salt or hydrogels fabricated from antimicrobial peptides (AMPs) or natural polymers, such as chitosan. A summary of the different alternatives employed for this purpose is described in this review, considering their advantages and disadvantages. Finally, more recent methodologies that lead to more sophisticated hydrogels that are able to react to external stimuli are equally depicted in this review.

Advances in the Fabrication of Antimicrobial Hydrogels for Biomedical Applications

PubMed Central

González-Henríquez, Carmen M.; Sarabia-Vallejos, Mauricio A.; Rodriguez-Hernandez, Juan

2017-01-01

This review describes, in an organized manner, the recent developments in the elaboration of hydrogels that possess antimicrobial activity. The fabrication of antibacterial hydrogels for biomedical applications that permits cell adhesion and proliferation still remains as an interesting challenge, in particular for tissue engineering applications. In this context, a large number of studies has been carried out in the design of hydrogels that serve as support for antimicrobial agents (nanoparticles, antibiotics, etc.). Another interesting approach is to use polymers with inherent antimicrobial activity provided by functional groups contained in their structures, such as quaternary ammonium salt or hydrogels fabricated from antimicrobial peptides (AMPs) or natural polymers, such as chitosan. A summary of the different alternatives employed for this purpose is described in this review, considering their advantages and disadvantages. Finally, more recent methodologies that lead to more sophisticated hydrogels that are able to react to external stimuli are equally depicted in this review. PMID:28772591

Selection of Single-Walled Carbon Nanotube with Narrow Diameter Distribution by Using a PPE PPV Copolymer

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

Perry, Kelly A; Chen, Yusheng; Malkovskiy, Andrey

2012-01-01

Electronic and mechanic properties of single-walled carbon nanotubes (SWNTs) are uniquely dependent on the tube's chiralities and diameters. Isolation of different type SWNTs remains one of the fundamental and challenging issues in nanotube science. Herein, we demonstrate that SWNTs can be effectively enriched to a narrow diameter range by sequential treatment of the HiPco sample with nitric acid and a {pi}-conjugated copolymer poly(phenyleneethynylene) (PPE)-co-poly(phenylenevinylene) (PPV). On the basis of Raman, fluorescence, and microscopic evidence, the nitric acid is found to selectively remove the SWNTs of small diameter. The polymer not only effectively dispersed carbon nanotubes but also exhibited a goodmore » selectivity toward a few SWNTs. The reported approach thus offers a new methodology to isolate SWNTs, which has the potential to operate in a relatively large scale.« less

Electron microscopy approach for the visualization of the epithelial and endothelial glycocalyx.

PubMed

Chevalier, L; Selim, J; Genty, D; Baste, J M; Piton, N; Boukhalfa, I; Hamzaoui, M; Pareige, P; Richard, V

2017-06-01

This study presents a methodological approach for the visualization of the glycocalyx by electron microscopy. The glycocalyx is a three dimensional network mainly composed of glycolipids, glycoproteins and proteoglycans associated with the plasma membrane. Since less than a decade, the epithelial and endothelial glycocalyx proved to play an important role in physiology and pathology, increasing its research interest especially in vascular functions. Therefore, visualization of the glycocalyx requires reliable techniques and its preservation remains challenging due to its fragile and dynamic organization, which is highly sensitive to the different process steps for electron microscopy sampling. In this study, chemical fixation was performed by perfusion as a good alternative to conventional fixation. Additional lanthanum nitrate in the fixative enhances staining of the glycocalyx in transmission electron microscopy bright field and improves its visualization by detecting the elastic scattered electrons, thus providing a chemical contrast. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Composite SAR imaging using sequential joint sparsity

NASA Astrophysics Data System (ADS)

Sanders, Toby; Gelb, Anne; Platte, Rodrigo B.

2017-06-01

This paper investigates accurate and efficient ℓ1 regularization methods for generating synthetic aperture radar (SAR) images. Although ℓ1 regularization algorithms are already employed in SAR imaging, practical and efficient implementation in terms of real time imaging remain a challenge. Here we demonstrate that fast numerical operators can be used to robustly implement ℓ1 regularization methods that are as or more efficient than traditional approaches such as back projection, while providing superior image quality. In particular, we develop a sequential joint sparsity model for composite SAR imaging which naturally combines the joint sparsity methodology with composite SAR. Our technique, which can be implemented using standard, fractional, or higher order total variation regularization, is able to reduce the effects of speckle and other noisy artifacts with little additional computational cost. Finally we show that generalizing total variation regularization to non-integer and higher orders provides improved flexibility and robustness for SAR imaging.

Study of Blood-transfusion Services in Maharashtra and Gujarat States, India

PubMed Central

Ramani, K.V.; Govil, Dipti

2009-01-01

Blood-transfusion services are vital to maternal health because haemorrhage and anaemia are major causes of maternal death in South Asia. Unfortunately, due to continued governmental negligence, blood-transfusion services in India are a highly-fragmented mix of competing independent and hospital-based blood-banks, serving the needs of urban populations. This paper aims to understand the existing systems of blood-transfusion services in India focusing on Maharashtra and Gujarat states. A mix of methodologies, including literature review (including government documents), analysis of management information system data, and interviews with key officials was used. Results of analysis showed that there are many managerial challenges in blood-transfusion services, which calls for strengthening the planning and monitoring of these services. Maharashtra provides a good model for improvement. Unless this is done, access to blood in rural areas may remain poor. PMID:19489420

Unraveling dynamics of human physical activity patterns in chronic pain conditions

NASA Astrophysics Data System (ADS)

Paraschiv-Ionescu, Anisoara; Buchser, Eric; Aminian, Kamiar

2013-06-01

Chronic pain is a complex disabling experience that negatively affects the cognitive, affective and physical functions as well as behavior. Although the interaction between chronic pain and physical functioning is a well-accepted paradigm in clinical research, the understanding of how pain affects individuals' daily life behavior remains a challenging task. Here we develop a methodological framework allowing to objectively document disruptive pain related interferences on real-life physical activity. The results reveal that meaningful information is contained in the temporal dynamics of activity patterns and an analytical model based on the theory of bivariate point processes can be used to describe physical activity behavior. The model parameters capture the dynamic interdependence between periods and events and determine a `signature' of activity pattern. The study is likely to contribute to the clinical understanding of complex pain/disease-related behaviors and establish a unified mathematical framework to quantify the complex dynamics of various human activities.

Decarboxylative alkylation for site-selective bioconjugation of native proteins via oxidation potentials

NASA Astrophysics Data System (ADS)

Bloom, Steven; Liu, Chun; Kölmel, Dominik K.; Qiao, Jennifer X.; Zhang, Yong; Poss, Michael A.; Ewing, William R.; MacMillan, David W. C.

2018-02-01

The advent of antibody-drug conjugates as pharmaceuticals has fuelled a need for reliable methods of site-selective protein modification that furnish homogeneous adducts. Although bioorthogonal methods that use engineered amino acids often provide an elegant solution to the question of selective functionalization, achieving homogeneity using native amino acids remains a challenge. Here, we explore visible-light-mediated single-electron transfer as a mechanism towards enabling site- and chemoselective bioconjugation. Specifically, we demonstrate the use of photoredox catalysis as a platform to selectivity wherein the discrepancy in oxidation potentials between internal versus C-terminal carboxylates can be exploited towards obtaining C-terminal functionalization exclusively. This oxidation potential-gated technology is amenable to endogenous peptides and has been successfully demonstrated on the protein insulin. As a fundamentally new approach to bioconjugation this methodology provides a blueprint toward the development of photoredox catalysis as a generic platform to target other redox-active side chains for native conjugation.

Centimetre-scale micropore alignment in oriented polycrystalline metal-organic framework films via heteroepitaxial growth.

PubMed

Falcaro, Paolo; Okada, Kenji; Hara, Takaaki; Ikigaki, Ken; Tokudome, Yasuaki; Thornton, Aaron W; Hill, Anita J; Williams, Timothy; Doonan, Christian; Takahashi, Masahide

2017-03-01

The fabrication of oriented, crystalline films of metal-organic frameworks (MOFs) is a critical step toward their application to advanced technologies such as optics, microelectronics, microfluidics and sensing. However, the direct synthesis of MOF films with controlled crystalline orientation remains a significant challenge. Here we report a one-step approach, carried out under mild conditions, that exploits heteroepitaxial growth for the rapid fabrication of oriented polycrystalline MOF films on the centimetre scale. Our methodology employs crystalline copper hydroxide as a substrate and yields MOF films with oriented pore channels on scales that primarily depend on the dimensions of the substrate. To demonstrate that an anisotropic crystalline morphology can translate to a functional property, we assembled a centimetre-scale MOF film in the presence of a dye and showed that the optical response could be switched 'ON' or 'OFF' by simply rotating the film.

A facile molten-salt route to graphene synthesis.

PubMed

Liu, Xiaofeng; Giordano, Cristina; Antonietti, Markus

2014-01-15

Efficient synthetic routes are continuously pursued for graphene in order to implement its applications in different areas. However, direct conversion of simple monomers to graphene through polymerization in a scalable manner remains a major challenge for chemists. Herein, a molten-salt (MS) route for the synthesis of carbon nanostructures and graphene by controlled carbonization of glucose in molten metal chloride is reported. In this process, carbohydrate undergoes polymerization in the presence of strongly interacting ionic species, which leads to nanoporous carbon with amorphous nature and adjustable pore size. At a low precursor concentration, the process converts the sugar molecules (glucose) to rather pure few-layer graphenes. The MS-derived graphenes are strongly hydrophobic and exhibit remarkable selectivity and capacity for absorption of organics. The methodology described may open up a new avenue towards the synthesis and manipulation of carbon materials in liquid media. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Power Approaches for Implantable Medical Devices.

PubMed

Ben Amar, Achraf; Kouki, Ammar B; Cao, Hung

2015-11-13

Implantable medical devices have been implemented to provide treatment and to assess in vivo physiological information in humans as well as animal models for medical diagnosis and prognosis, therapeutic applications and biological science studies. The advances of micro/nanotechnology dovetailed with novel biomaterials have further enhanced biocompatibility, sensitivity, longevity and reliability in newly-emerged low-cost and compact devices. Close-loop systems with both sensing and treatment functions have also been developed to provide point-of-care and personalized medicine. Nevertheless, one of the remaining challenges is whether power can be supplied sufficiently and continuously for the operation of the entire system. This issue is becoming more and more critical to the increasing need of power for wireless communication in implanted devices towards the future healthcare infrastructure, namely mobile health (m-Health). In this review paper, methodologies to transfer and harvest energy in implantable medical devices are introduced and discussed to highlight the uses and significances of various potential power sources.

Ocean Data Assimilation in Support of Climate Applications: Status and Perspectives.

PubMed

Stammer, D; Balmaseda, M; Heimbach, P; Köhl, A; Weaver, A

2016-01-01

Ocean data assimilation brings together observations with known dynamics encapsulated in a circulation model to describe the time-varying ocean circulation. Its applications are manifold, ranging from marine and ecosystem forecasting to climate prediction and studies of the carbon cycle. Here, we address only climate applications, which range from improving our understanding of ocean circulation to estimating initial or boundary conditions and model parameters for ocean and climate forecasts. Because of differences in underlying methodologies, data assimilation products must be used judiciously and selected according to the specific purpose, as not all related inferences would be equally reliable. Further advances are expected from improved models and methods for estimating and representing error information in data assimilation systems. Ultimately, data assimilation into coupled climate system components is needed to support ocean and climate services. However, maintaining the infrastructure and expertise for sustained data assimilation remains challenging.

Inner Speech: Development, Cognitive Functions, Phenomenology, and Neurobiology

PubMed Central

2015-01-01

Inner speech—also known as covert speech or verbal thinking—has been implicated in theories of cognitive development, speech monitoring, executive function, and psychopathology. Despite a growing body of knowledge on its phenomenology, development, and function, approaches to the scientific study of inner speech have remained diffuse and largely unintegrated. This review examines prominent theoretical approaches to inner speech and methodological challenges in its study, before reviewing current evidence on inner speech in children and adults from both typical and atypical populations. We conclude by considering prospects for an integrated cognitive science of inner speech, and present a multicomponent model of the phenomenon informed by developmental, cognitive, and psycholinguistic considerations. Despite its variability among individuals and across the life span, inner speech appears to perform significant functions in human cognition, which in some cases reflect its developmental origins and its sharing of resources with other cognitive processes. PMID:26011789

MetaSort untangles metagenome assembly by reducing microbial community complexity

PubMed Central

Ji, Peifeng; Zhang, Yanming; Wang, Jinfeng; Zhao, Fangqing

2017-01-01

Most current approaches to analyse metagenomic data rely on reference genomes. Novel microbial communities extend far beyond the coverage of reference databases and de novo metagenome assembly from complex microbial communities remains a great challenge. Here we present a novel experimental and bioinformatic framework, metaSort, for effective construction of bacterial genomes from metagenomic samples. MetaSort provides a sorted mini-metagenome approach based on flow cytometry and single-cell sequencing methodologies, and employs new computational algorithms to efficiently recover high-quality genomes from the sorted mini-metagenome by the complementary of the original metagenome. Through extensive evaluations, we demonstrated that metaSort has an excellent and unbiased performance on genome recovery and assembly. Furthermore, we applied metaSort to an unexplored microflora colonized on the surface of marine kelp and successfully recovered 75 high-quality genomes at one time. This approach will greatly improve access to microbial genomes from complex or novel communities. PMID:28112173

Wavefront modulation and subwavelength diffractive acoustics with an acoustic metasurface.

PubMed

Xie, Yangbo; Wang, Wenqi; Chen, Huanyang; Konneker, Adam; Popa, Bogdan-Ioan; Cummer, Steven A

2014-11-24

Metasurfaces are a family of novel wavefront-shaping devices with planar profile and subwavelength thickness. Acoustic metasurfaces with ultralow profile yet extraordinary wave manipulating properties would be highly desirable for improving the performance of many acoustic wave-based applications. However, designing acoustic metasurfaces with similar functionality to their electromagnetic counterparts remains challenging with traditional metamaterial design approaches. Here we present a design and realization of an acoustic metasurface based on tapered labyrinthine metamaterials. The demonstrated metasurface can not only steer an acoustic beam as expected from the generalized Snell's law, but also exhibits various unique properties such as conversion from propagating wave to surface mode, extraordinary beam-steering and apparent negative refraction through higher-order diffraction. Such designer acoustic metasurfaces provide a new design methodology for acoustic signal modulation devices and may be useful for applications such as acoustic imaging, beam steering, ultrasound lens design and acoustic surface wave-based applications.

Tumor infiltrating lymphocytes in ovarian cancer

PubMed Central

Santoiemma, Phillip P; Powell, Daniel J

2015-01-01

The accumulation of tumor infiltrating lymphocytes (TILs) in ovarian cancer is prognostic for increased survival while increases in immunosuppressive regulatory T-cells (Tregs) are associated with poor outcomes. Approaches that bolster tumor-reactive TILs may limit tumor progression. However, identifying tumor-reactive TILs in ovarian cancer has been challenging, though adoptive TIL therapy in patients has been encouraging. Other forms of TIL immunomodulation remain under investigation including Treg depletion, antibody-based checkpoint modification, activation and amplification using dendritic cells, antigen presenting cells or IL-2 cytokine culture, adjuvant cytokine injections, and gene-engineered T-cells. Many approaches to TIL manipulation inhibit ovarian cancer progression in preclinical or clinical studies as monotherapy. Here, we review the impact of TILs in ovarian cancer and attempts to mobilize TILs to halt tumor progression. We conclude that effective TIL therapy for ovarian cancer is at the brink of translation and optimal TIL activity may require combined methodologies to deliver clinically-relevant treatment. PMID:25894333

Human Microbiome and HIV/AIDS

PubMed Central

Li, Yihong; Yang, Liying; Pei, Zhiheng; Poles, Michael; Abrams, William R.; Malamud, Daniel

2013-01-01

Understanding of the human microbiome continues to grow rapidly; however, reports on changes in the microbiome after HIV infection are still limited. This review surveys the progress made in methodology associated with microbiome studies and highlights the remaining challenges to this field. Studies have shown that commensal oral, gut, vaginal, and penile bacteria are vital to the health of the human immune system. Our studies on crosstalk among oral and gastrointestinal soluble innate factors, HIV, and microbes indicated that the oral and gut microbiome was altered in the HIV-positive samples compared to the negative controls. The importance of understanding the bacterial component of HIV/AIDS, and likelihood of “crosstalk” between viral and bacterial pathogens, will help in understanding the role of the microbiome in HIV-infected individuals and facilitate identification of novel antiretroviral factors for use as novel diagnostics, microbicides, or therapeutics against HIV infection. PMID:22193889

Future WGCEP Models and the Need for Earthquake Simulators

NASA Astrophysics Data System (ADS)

Field, E. H.

2008-12-01

The 2008 Working Group on California Earthquake Probabilities (WGCEP) recently released the Uniform California Earthquake Rupture Forecast version 2 (UCERF 2), developed jointly by the USGS, CGS, and SCEC with significant support from the California Earthquake Authority. Although this model embodies several significant improvements over previous WGCEPs, the following are some of the significant shortcomings that we hope to resolve in a future UCERF3: 1) assumptions of fault segmentation and the lack of fault-to-fault ruptures; 2) the lack of an internally consistent methodology for computing time-dependent, elastic-rebound-motivated renewal probabilities; 3) the lack of earthquake clustering/triggering effects; and 4) unwarranted model complexity. It is believed by some that physics-based earthquake simulators will be key to resolving these issues, either as exploratory tools to help guide the present statistical approaches, or as a means to forecast earthquakes directly (although significant challenges remain with respect to the latter).

Ductile failure X-prize.

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

Cox, James V.; Wellman, Gerald William; Emery, John M.

2011-09-01

Fracture or tearing of ductile metals is a pervasive engineering concern, yet accurate prediction of the critical conditions of fracture remains elusive. Sandia National Laboratories has been developing and implementing several new modeling methodologies to address problems in fracture, including both new physical models and new numerical schemes. The present study provides a double-blind quantitative assessment of several computational capabilities including tearing parameters embedded in a conventional finite element code, localization elements, extended finite elements (XFEM), and peridynamics. For this assessment, each of four teams reported blind predictions for three challenge problems spanning crack initiation and crack propagation. After predictionsmore » had been reported, the predictions were compared to experimentally observed behavior. The metal alloys for these three problems were aluminum alloy 2024-T3 and precipitation hardened stainless steel PH13-8Mo H950. The predictive accuracies of the various methods are demonstrated, and the potential sources of error are discussed.« less

Pore surface engineering in covalent organic frameworks.

PubMed

Nagai, Atsushi; Guo, Zhaoqi; Feng, Xiao; Jin, Shangbin; Chen, Xiong; Ding, Xuesong; Jiang, Donglin

2011-11-15

Covalent organic frameworks (COFs) are a class of important porous materials that allow atomically precise integration of building blocks to achieve pre-designable pore size and geometry; however, pore surface engineering in COFs remains challenging. Here we introduce pore surface engineering to COF chemistry, which allows the controlled functionalization of COF pore walls with organic groups. This functionalization is made possible by the use of azide-appended building blocks for the synthesis of COFs with walls to which a designable content of azide units is anchored. The azide units can then undergo a quantitative click reaction with alkynes to produce pore surfaces with desired groups and preferred densities. The diversity of click reactions performed shows that the protocol is compatible with the development of various specific surfaces in COFs. Therefore, this methodology constitutes a step in the pore surface engineering of COFs to realize pre-designed compositions, components and functions.

Beyond Utterances: Distributed Cognition as a Framework for Studying Discourse in Adults with Acquired Brain Injury

PubMed Central

Duff, Melissa C.; Mutlu, Bilge; Byom, Lindsey; Turkstra, Lyn S.

2014-01-01

Considerable effort has been directed at understanding the nature of the communicative deficits observed in individuals with acquired brain injuries. Yet several theoretical, methodological, and clinical challenges remain. In this article, we examine distributed cognition as a framework for understanding interaction among communication partners, interaction of communication and cognition, and interaction with the environments and contexts of everyday language use. We review the basic principles of distributed cognition and the implications for applying this approach to the study of discourse in individuals with cognitive-communication disorders. We also review a range of protocols and findings from our research that highlight how the distributed cognition approach might offer a deeper understanding of communicative mechanisms and deficits in individuals with cognitive communication impairments. The advantages and implications of distributed cognition as a framework for studying discourse in adults with acquired brain injury are discussed. PMID:22362323

Biophysical impacts of climate-smart agriculture in the Midwest United States

USDA-ARS?s Scientific Manuscript database

The potential impacts of climate change in the Midwest United States present unprecedented challenges to regional agriculture. In response to these challenges, a variety of climate-smart agricultural methodologies have been proposed to retain or improve crop yields, reduce agricultural greenhouse ga...

Sustainable Facility Development: Perceived Benefits and Challenges

ERIC Educational Resources Information Center

Stinnett, Brad; Gibson, Fred

2016-01-01

Purpose: The purpose of this paper is to assess the perceived benefits and challenges of implementing sustainable initiatives in collegiate recreational sports facilities. Additionally, this paper intends to contribute to the evolving field of facility sustainability in higher education. Design/methodology/approach The design included qualitative…

Researching the Interdisciplinary Curriculum: The Need for "Translation Devices"

ERIC Educational Resources Information Center

Pountney, Richard; McPhail, Graham

2017-01-01

This paper discusses the conceptual and methodological challenges facing two researchers investigating the development of interdisciplinary curricula in two new secondary schools, one in the UK and one in New Zealand. It is a discussion of research in progress that will be of interest to readers because of both the methodological challenges…

From Model to Methodology: Developing an Interdisciplinary Methodology for Exploring the Learning-Teaching Nexus

ERIC Educational Resources Information Center

Knewstubb, Bernadette; Nicholas, Howard

2017-01-01

Numerous higher education researchers have studied the ways in which students' or academics' beliefs and conceptions affect their educational experiences and outcomes. However, studying the learning-teaching relationship has proved challenging, requiring researchers to simultaneously address both the invisible internal world(s) of the student and…

ALLOCATING ENVIRONMENTAL BURDENS ACROSS CO-PRODUCTS TO CREATE A LIFE CYCLE INVENTORY: IS THERE A BEST WAY?

EPA Science Inventory

Allocation methodology for creating life cycle inventories is frequently addressed, discussed and debated, yet the methodology continues to be in a state of flux. ISO 14041 puts perspective on the issues but its one-size fits all framework is being challenged. It is clear that ...

Design Research with a Focus on Learning Processes: An Overview on Achievements and Challenges

ERIC Educational Resources Information Center

Prediger, Susanne; Gravemeijer, Koeno; Confrey, Jere

2015-01-01

Design research continues to gain prominence as a significant methodology in the mathematics education research community. This overview summarizes the origins and the current state of design research practices focusing on methodological requirements and processes of theorizing. While recognizing the rich variations in the foci and scale of design…

Reflective Pedagogy: The Integration of Methodology and Subject-Matter Content in a Graduate-Level Course

ERIC Educational Resources Information Center

Jakeman, Rick C.; Henderson, Markesha M.; Howard, Lionel C.

2017-01-01

This article presents a critical reflection on how we, instructors of a graduate-level course in higher education administration, sought to integrate theoretical and subject-matter content and research methodology. Our reflection, guided by autoethnography and teacher reflection, challenged both our assumptions about curriculum design and our…

Key Methodological Aspects of Translators' Training in Ukraine and in the USA

ERIC Educational Resources Information Center

Skyba, Kateryna

2015-01-01

The diversity of international relations in the globalized world has influenced the role of a translator that is becoming more and more important. Translators' training institutions today are to work out and to implement the best teaching methodology taking into consideration the new challenges of modern multinational and multicultural society.…

Harnessing the Power of Education Research Databases with the Pearl-Harvesting Methodological Framework for Information Retrieval

ERIC Educational Resources Information Center

Sandieson, Robert W.; Kirkpatrick, Lori C.; Sandieson, Rachel M.; Zimmerman, Walter

2010-01-01

Digital technologies enable the storage of vast amounts of information, accessible with remarkable ease. However, along with this facility comes the challenge to find pertinent information from the volumes of nonrelevant information. The present article describes the pearl-harvesting methodological framework for information retrieval. Pearl…

Training Emotional and Social Competences in Higher Education: The Seminar Methodology

ERIC Educational Resources Information Center

Oberst, Ursula; Gallifa, Josep; Farriols, Nuria; Vilaregut, Anna

2009-01-01

This article discusses the importance of emotional and social competences in higher education and presents a training model. In 1991, Ramon Llull University of Barcelona (Spain) created the Seminar methodology to tackle these challenges. A general model derived from the Emotional Intelligence concept and the general principles of this methodology…

Journeys into Inner/Outer Space: Reflections on the Methodological Challenges of Negotiating Insider/Outsider Status in International Educational Research

ERIC Educational Resources Information Center

Savvides, Nicola; Al-Youssef, Joanna; Colin, Mindy; Garrido, Cecilia

2014-01-01

This article highlights key theoretical and methodological issues and implications of being an insider/outsider when undertaking qualitative research in international educational settings. It first addresses discourses of "self" and "other," noting that identity and belonging emerge from fluid engagement between researchers and…

Methodological Issues and Practical Strategies in Research on Child Maltreatment Victims' Abilities and Experiences as Witnesses

ERIC Educational Resources Information Center

Chae, Yoojin; Goodman, Gail S.; Bederian-Gardner, Daniel; Lindsay, Adam

2011-01-01

Scientific studies of child maltreatment victims' memory abilities and court experiences have important legal, psychological, and clinical implications. However, state-of-the-art research on child witnesses is often hindered by methodological challenges. In this paper, we address specific problems investigators may encounter when attempting such…

"Charlie: Please Respond!" Using a Participatory Methodology with Individuals on the Autism Spectrum

ERIC Educational Resources Information Center

MacLeod, Andrea Georgia; Lewis, Ann; Robertson, Christopher

2014-01-01

This paper explores a participatory research approach used with 10 higher education students on the autism spectrum (mainly diagnosed with Asperger syndrome). The methodology sought to overcome barriers to participation. Participants' views were sought on the benefits and challenges related to their participation. Most participants opted for…

Methodologies for Effective Writing Instruction in EFL and ESL Classrooms

ERIC Educational Resources Information Center

Al-Mahrooqi, Rahma, Ed.; Thakur, Vijay Singh; Roscoe, Adrian

2015-01-01

Educators continue to strive for advanced teaching methods to bridge the gap between native and non-native English speaking students. Lessons on written forms of communication continue to be a challenge recognized by educators who wish to improve student comprehension and overall ability to write clearly and expressively. "Methodologies for…

Appraising the Ethos of Experiential Narratives: Key Aspects of a Methodological Challenge

ERIC Educational Resources Information Center

Conle, Carola; deBeyer, Michael

2009-01-01

In this essay, Carola Conle and Michael deBeyer describe their efforts to find a conceptual approach and methodology for the appraisal of the ethos of experiential narratives presented in a particular curriculum context. The language of "implied authorship," "the patterning of desire," and "friendships offered and received," first introduced by…

An E-Assessment Approach for Evaluation in Engineering Overcrowded Groups

ERIC Educational Resources Information Center

Mora, M. C.; Sancho-Bru, J. L.; Iserte, J. L.; Sanchez, F. T.

2012-01-01

The construction of the European Higher Education Area has been an adaptation challenge for Spanish universities. New methodologies require a more active role on the students' part and come into conflict with the previous educational model characterised by a high student/professor ratio, a lecture-based teaching methodology and a summative…

From the Analysis of Work-Processes to Designing Competence-Based Occupational Standards and Vocational Curricula

ERIC Educational Resources Information Center

Tutlys, Vidmantas; Spöttl, Georg

2017-01-01

Purpose: This paper aims to explore methodological and institutional challenges on application of the work-process analysis approach in the design and development of competence-based occupational standards for Lithuania. Design/methodology/approach: The theoretical analysis is based on the review of scientific literature and the analysis of…

Speaking Back to the Deficit Discourses: A Theoretical and Methodological Approach

ERIC Educational Resources Information Center

Hogarth, Melitta

2017-01-01

The educational attainment of Aboriginal and Torres Strait Islander students is often presented within a deficit view. The need for Aboriginal and Torres Strait Islander researchers to challenge the societal norms is necessary to contribute to the struggle for self-determination. This paper presents a theoretical and methodological approach that…

Practicing the Four Seasons of Ethnography Methodology while Searching for Identity in Mexico

ERIC Educational Resources Information Center

Pitts, Margaret Jane

2012-01-01

This narrative is an account of my field experiences and challenges practicing Gonzalez's (2000) Four Seasons of Ethnography methodology in Mexico City. I describe the complexities and tensions inherent in managing two scientific paradigms: Western scientific logic vs. a more organic ontology. The experiential knowledge produced in this text is…

Exploring Emotion in the Higher Education Workplace: Capturing Contrasting Perspectives Using Q Methodology

ERIC Educational Resources Information Center

Woods, Charlotte

2012-01-01

This article presents an original application of Q methodology in investigating the challenging arena of emotion in the Higher Education (HE) workplace. Q's strength lies in capturing holistic, subjective accounts of complex and contested phenomena but is unusual in employing a statistical procedure within an interpretivist framework. Here Q is…

Opportunities and methodological challenges in EEG and MEG resting state functional brain network research.

PubMed

van Diessen, E; Numan, T; van Dellen, E; van der Kooi, A W; Boersma, M; Hofman, D; van Lutterveld, R; van Dijk, B W; van Straaten, E C W; Hillebrand, A; Stam, C J

2015-08-01

Electroencephalogram (EEG) and magnetoencephalogram (MEG) recordings during resting state are increasingly used to study functional connectivity and network topology. Moreover, the number of different analysis approaches is expanding along with the rising interest in this research area. The comparison between studies can therefore be challenging and discussion is needed to underscore methodological opportunities and pitfalls in functional connectivity and network studies. In this overview we discuss methodological considerations throughout the analysis pipeline of recording and analyzing resting state EEG and MEG data, with a focus on functional connectivity and network analysis. We summarize current common practices with their advantages and disadvantages; provide practical tips, and suggestions for future research. Finally, we discuss how methodological choices in resting state research can affect the construction of functional networks. When taking advantage of current best practices and avoid the most obvious pitfalls, functional connectivity and network studies can be improved and enable a more accurate interpretation and comparison between studies. Copyright © 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Critical Perspectives on Methodology in Pedagogic Research

ERIC Educational Resources Information Center

Kahn, Peter

2015-01-01

The emancipatory dimension to higher education represents one of the sector's most compelling characteristics, but it remains important to develop understanding of the sources of determination that shape practice. Drawing on critical realist perspectives, we explore generative mechanisms by which methodology in pedagogic research affects the…

Validation of metabolomics analysis of human perilymph fluid using liquid chromatography-mass spectroscopy.

PubMed

Mavel, Sylvie; Lefèvre, Antoine; Bakhos, David; Dufour-Rainfray, Diane; Blasco, Hélène; Emond, Patrick

2018-05-22

Although there is some data from animal studies, the metabolome of inner ear fluid in humans remains unknown. Characterization of the metabolome of the perilymph would allow for better understanding of its role in auditory function and for identification of biomarkers that might allow prediction of response to therapeutics. There is a major technical challenge due to the small sample of perilymph fluid available for analysis (sub-microliter). The objectives of this study were to develop and validate a methodology for analysis of perilymph metabolome using liquid chromatography-high resolution mass spectrometry (LC-HRMS). Due to the low availability of perilymph fluid; a methodological study was first performed using low volumes (0.8 μL) of cerebrospinal fluid (CSF) and optimized the LC-HRMS parameters using targeted and non-targeted metabolomics approaches. We obtained excellent parameters of reproducibility for about 100 metabolites. This methodology was then used to analyze perilymph fluid using two complementary chromatographic supports: reverse phase (RP-C18) and hydrophilic interaction liquid chromatography (HILIC). Both methods were highly robust and showed their complementarity, thus reinforcing the interest to combine these chromatographic supports. A fingerprinting was obtained from 98 robust metabolites (analytical variability <30%), where amino acids (e.g., asparagine, valine, glutamine, alanine, etc.), carboxylic acids and derivatives (e.g., lactate, carnitine, trigonelline, creatinine, etc.) were observed as first-order signals. This work lays the foundations of a robust analytical workflow for the exploration of the perilymph metabolome dedicated to the research of biomarkers for the diagnosis/prognosis of auditory pathologies. Copyright © 2018 Elsevier B.V. All rights reserved.

Learning-based stochastic object models for characterizing anatomical variations

NASA Astrophysics Data System (ADS)

Dolly, Steven R.; Lou, Yang; Anastasio, Mark A.; Li, Hua

2018-03-01

It is widely known that the optimization of imaging systems based on objective, task-based measures of image quality via computer-simulation requires the use of a stochastic object model (SOM). However, the development of computationally tractable SOMs that can accurately model the statistical variations in human anatomy within a specified ensemble of patients remains a challenging task. Previously reported numerical anatomic models lack the ability to accurately model inter-patient and inter-organ variations in human anatomy among a broad patient population, mainly because they are established on image data corresponding to a few of patients and individual anatomic organs. This may introduce phantom-specific bias into computer-simulation studies, where the study result is heavily dependent on which phantom is used. In certain applications, however, databases of high-quality volumetric images and organ contours are available that can facilitate this SOM development. In this work, a novel and tractable methodology for learning a SOM and generating numerical phantoms from a set of volumetric training images is developed. The proposed methodology learns geometric attribute distributions (GAD) of human anatomic organs from a broad patient population, which characterize both centroid relationships between neighboring organs and anatomic shape similarity of individual organs among patients. By randomly sampling the learned centroid and shape GADs with the constraints of the respective principal attribute variations learned from the training data, an ensemble of stochastic objects can be created. The randomness in organ shape and position reflects the learned variability of human anatomy. To demonstrate the methodology, a SOM of an adult male pelvis is computed and examples of corresponding numerical phantoms are created.

Ancient DNA studies: new perspectives on old samples

PubMed Central

2012-01-01

In spite of past controversies, the field of ancient DNA is now a reliable research area due to recent methodological improvements. A series of recent large-scale studies have revealed the true potential of ancient DNA samples to study the processes of evolution and to test models and assumptions commonly used to reconstruct patterns of evolution and to analyze population genetics and palaeoecological changes. Recent advances in DNA technologies, such as next-generation sequencing make it possible to recover DNA information from archaeological and paleontological remains allowing us to go back in time and study the genetic relationships between extinct organisms and their contemporary relatives. With the next-generation sequencing methodologies, DNA sequences can be retrieved even from samples (for example human remains) for which the technical pitfalls of classical methodologies required stringent criteria to guaranty the reliability of the results. In this paper, we review the methodologies applied to ancient DNA analysis and the perspectives that next-generation sequencing applications provide in this field. PMID:22697611

Design strategies from sexual exploitation and sex work studies among women and girls: Methodological considerations in a hidden and vulnerable population.

PubMed

Gerassi, Lara; Edmond, Tonya; Nichols, Andrea

2017-06-01

The study of sex trafficking, prostitution, sex work, and sexual exploitation is associated with many methodological issues and challenges. Researchers' study designs must consider the many safety issues related to this vulnerable and hidden population. Community advisory boards and key stakeholder involvement are essential to study design to increase safety of participants, usefulness of study aims, and meaningfulness of conclusions. Nonrandomized sampling strategies are most often utilized when studying exploited women and girls, which have the capacity to provide rich data and require complex sampling and recruitment methods. This article reviews the current methodological issues when studying this marginalized population as well as strategies to address challenges while working with the community in order to bring about social change. The authors also discuss their own experiences in collaborating with community organizations to conduct research in this field.

Design strategies from sexual exploitation and sex work studies among women and girls: Methodological considerations in a hidden and vulnerable population

PubMed Central

Gerassi, Lara; Edmond, Tonya; Nichols, Andrea

2016-01-01

The study of sex trafficking, prostitution, sex work, and sexual exploitation is associated with many methodological issues and challenges. Researchers’ study designs must consider the many safety issues related to this vulnerable and hidden population. Community advisory boards and key stakeholder involvement are essential to study design to increase safety of participants, usefulness of study aims, and meaningfulness of conclusions. Nonrandomized sampling strategies are most often utilized when studying exploited women and girls, which have the capacity to provide rich data and require complex sampling and recruitment methods. This article reviews the current methodological issues when studying this marginalized population as well as strategies to address challenges while working with the community in order to bring about social change. The authors also discuss their own experiences in collaborating with community organizations to conduct research in this field. PMID:28824337

The development of capability measures in health economics: opportunities, challenges and progress.

PubMed

Coast, Joanna; Kinghorn, Philip; Mitchell, Paul

2015-04-01

Recent years have seen increased engagement amongst health economists with the capability approach developed by Amartya Sen and others. This paper focuses on the capability approach in relation to the evaluative space used for analysis within health economics. It considers the opportunities that the capability approach offers in extending this space, but also the methodological challenges associated with moving from the theoretical concepts to practical empirical applications. The paper then examines three 'families' of measures, Oxford Capability instruments (OxCap), Adult Social Care Outcome Toolkit (ASCOT) and ICEpop CAPability (ICECAP), in terms of the methodological choices made in each case. The paper concludes by discussing some of the broader issues involved in making use of the capability approach in health economics. It also suggests that continued exploration of the impact of different methodological choices will be important in moving forward.

Possible Improvements of the ACE Diversity Interchange Methodology

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

Etingov, Pavel V.; Zhou, Ning; Makarov, Yuri V.

2010-07-26

North American Electric Reliability Corporation (NERC) grid is operated by about 131 balancing authorities (BA). Within each BA, operators are responsible for managing the unbalance (caused by both load and wind). As wind penetration levels increase, the challenges of managing power variation increases. Working independently, balancing area with limited regulating/load following generation and high wind power penetration faces significant challenges. The benefits of BA cooperation and consolidation increase when there is a significant wind energy penetration. To explore the benefits of BA cooperation, this paper investigates ACE sharing approach. A technology called ACE diversity interchange (ADI) is already in usemore » in the western interconnection. A new methodology extending ADI is proposed in the paper. The proposed advanced ADI overcoming some limitations existing in conventional ADI. Simulations using real statistical data of CAISO and BPA have shown high performance of the proposed advanced ADI methodology.« less

Methodological challenges collecting parent phone-call healthcare utilization data.

PubMed

Moreau, Paula; Crawford, Sybil; Sullivan-Bolyai, Susan

2016-02-01

Recommendations by the National Institute of Nursing Research and other groups have strongly encouraged nurses to pay greater attention to cost-effectiveness analysis when conducting research. Given the increasing prominence of translational science and comparative effective research, cost-effective analysis has become a basic tool in determining intervention value in research. Tracking phone-call communication (number of calls and context) with cross-checks between parents and healthcare providers is an example of this type of healthcare utilization data collection. This article identifies some methodological challenges that have emerged in the process of collecting this type of data in a randomized controlled trial: Parent education Through Simulation-Diabetes (PETS-D). We also describe ways in which those challenges have been addressed with comparison data results, and make recommendations for future research. Copyright © 2015 Elsevier Inc. All rights reserved.

Experiences of Structured Elicitation for Model-Based Cost-Effectiveness Analyses.

PubMed

Soares, Marta O; Sharples, Linda; Morton, Alec; Claxton, Karl; Bojke, Laura

2018-06-01

Empirical evidence supporting the cost-effectiveness estimates of particular health care technologies may be limited, or it may even be missing entirely. In these situations, additional information, often in the form of expert judgments, is needed to reach a decision. There are formal methods to quantify experts' beliefs, termed as structured expert elicitation (SEE), but only limited research is available in support of methodological choices. Perhaps as a consequence, the use of SEE in the context of cost-effectiveness modelling is limited. This article reviews applications of SEE in cost-effectiveness modelling with the aim of summarizing the basis for methodological choices made in each application and recording the difficulties and challenges reported by the authors in the design, conduct, and analyses. The methods used in each application were extracted along with the criteria used to support methodological and practical choices and any issues or challenges discussed in the text. Issues and challenges were extracted using an open field, and then categorised and grouped for reporting. The review demonstrates considerable heterogeneity in methods used, and authors acknowledge great methodological uncertainty in justifying their choices. Specificities of the context area emerging as potentially important in determining further methodological research in elicitation are between- expert variation and its interpretation, the fact that substantive experts in the area may not be trained in quantitative subjects, that judgments are often needed on various parameter types, the need for some form of assessment of validity, and the need for more integration with behavioural research to devise relevant debiasing strategies. This review of experiences of SEE highlights a number of specificities/constraints that can shape the development of guidance and target future research efforts in this area. Copyright © 2018 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Inernational research in health care management: its need in the 21st century, methodological challenges, ethical issues, pitfalls, and practicalities.

PubMed

Buttigieg, Sandra C; Rathert, Cheryl; D'Aunno, Thomas A; Savage, Grant T

2015-01-01

This commentary argues in favor of international research in the 21st century. Advances in technology, science, communication, transport, and infrastructure have transformed the world into a global village. Industries have increasingly adopted globalization strategies. Likewise, the health sector is more internationalized whereby comparisons between diverse health systems, international best practices, international benchmarking, cross-border health care, and cross-cultural issues have become important subjects in the health care literature. The focus has now turned to international, collaborative, cross-national, and cross-cultural research, which is by far more demanding than domestic studies. In this commentary, we explore the methodological challenges, ethical issues, pitfalls, and practicalities within international research and offer possible solutions to address them. The commentary synthesizes contributions from four scholars in the field of health care management, who came together during the annual meeting of the Academy of Management to discuss with members of the Health Care Management Division the challenges of international research. International research is worth pursuing; however, it calls for scholarly attention to key methodological and ethical issues for its success. This commentary addresses salient issues pertaining to international research in one comprehensive account.

Common methodologies in the evaluation of food allergy: pitfalls and prospects of food allergy prevalence studies.

PubMed

Shu, Shang-an; Chang, Christopher; Leung, Patrick S C

2014-06-01

Global and regional studies on the prevalence of food allergies are plagued by inconsistent methodologies, variations in interpretation of results, and non-standardized study design. Hence, it becomes difficult to compare the prevalence of food allergies in different communities. This information would be useful in providing critical data that will enhance research to elucidate the nature of food allergies, and the role of gene-environment interactions in the sensitization of children and adults to foods. Testing methodologies range from questionnaires to objective in vitro and in vivo testing, to the gold standard, double-blind placebo-controlled food challenge (DBPCFC). Although considered the most accurate and reliable method in detecting the prevalence of food allergy, DBPCFC is not always practical in epidemiological studies of food allergy. On the other hand, multiple logistic regression studies have been done to determine predictability of the outcome of food challenges, and it appears that skin prick testing and in vitro-specific serum IgE are the best predictors. Future studies directed towards confirming the validity of these methods as well as developing algorithms to predict the food challenge outcomes are required, as they may someday become accessory tools to complement DBPCFC.

Socio-Hydrology: Conceptual and Methodological Challenges in the Bidirectional Coupling of Human and Water Systems

NASA Astrophysics Data System (ADS)

Scott, C. A.

2014-12-01

This presentation reviews conceptual advances in the emerging field of socio-hydrology that focuses on coupled human and water systems. An important current challenge is how to better couple the bidirectional influences between human and water systems, which lead to emergent dynamics. The interactions among (1) the structure and dynamics of systems with (2) human values and norms lead to (3) outcomes, which in turn influence subsequent interactions. Human influences on hydrological systems are relatively well understood, chiefly resulting from developments in the field of water resources. The ecosystem-service concept of cultural value has expanded understanding of decision-making beyond economic rationality criteria. Hydrological impacts on social processes are less well developed conceptually, but this is changing with growing attention to vulnerability, adaptation, and resilience, particularly in the face of climate change. Methodological limitations, especially in characterizing the range of human responses to hydrological events and drivers, still pose challenges to modeling bidirectional human-water influences. Evidence from multiple case studies, synthesized in more broadly generic syndromes, helps surmount these methodological limitations and offers the potential to improve characterization and quantification of socio-hydrological systems.

Teaching OOA: Issues and Challenges.

ERIC Educational Resources Information Center

Sim, Edward

This paper presents the argument that object oriented analysis (OOA) is rapidly becoming an important systems analysis methodology and that current systems analysis and design courses should present OOA. However, because of the embryonic nature and rapidly changing content of OOA, instructors are faced with special challenges when designing OOA…

The utility of arginine-citrulline stable isotope tracer infusion technique in the assessment of nitric oxide production in MELAS syndrome

USDA-ARS?s Scientific Manuscript database

The correspondence titled “Analytical challenges in the assessment of NO synthesis from L-arginine in the MELAS syndrome” suggested challenges that can limit the utility of stable isotope infusion methodology in assessing NO production....

Challenging the Stereotypes of Mexican American Fathers

ERIC Educational Resources Information Center

Saracho, Olivia N.; Spodek, Bernard

2007-01-01

This critical review presents studies of Mexican American fathers in the United Sates to provide researchers with an understanding of contemporary fatherhood. It describes the myths that cause methodological and conceptual problems in interpreting the results of studies on Mexican American fathers. Several common challenges and limitations in…

Sex Work Research: Methodological and Ethical Challenges

ERIC Educational Resources Information Center

Shaver, Frances M.

2005-01-01

The challenges involved in the design of ethical, nonexploitative research projects with sex workers or any other marginalized population are significant. First, the size and boundaries of the population are unknown, making it extremely difficult to get a representative sample. Second, because membership in hidden populations often involves…

Development of 3D pseudo pin-by-pin calculation methodology in ANC

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

Zhang, B.; Mayhue, L.; Huria, H.

2012-07-01

Advanced cores and fuel assembly designs have been developed to improve operational flexibility, economic performance and further enhance safety features of nuclear power plants. The simulation of these new designs, along with strong heterogeneous fuel loading, have brought new challenges to the reactor physics methodologies currently employed in the industrial codes for core analyses. Control rod insertion during normal operation is one operational feature in the AP1000{sup R} plant of Westinghouse next generation Pressurized Water Reactor (PWR) design. This design improves its operational flexibility and efficiency but significantly challenges the conventional reactor physics methods, especially in pin power calculations. Themore » mixture loading of fuel assemblies with significant neutron spectrums causes a strong interaction between different fuel assembly types that is not fully captured with the current core design codes. To overcome the weaknesses of the conventional methods, Westinghouse has developed a state-of-the-art 3D Pin-by-Pin Calculation Methodology (P3C) and successfully implemented in the Westinghouse core design code ANC. The new methodology has been qualified and licensed for pin power prediction. The 3D P3C methodology along with its application and validation will be discussed in the paper. (authors)« less

Applying a contemporary grounded theory methodology.

PubMed

Licqurish, Sharon; Seibold, Carmel

2011-01-01

The aim of this paper is to discuss the application of a contemporary grounded theory methodology to a research project exploring the experiences of students studying for a degree in midwifery. Grounded theory is a qualitative research approach developed by Glaser and Strauss in the 1950s but the methodology for this study was modelled on Clarke's (2005) approach and was underpinned by a symbolic interactionist theoretical perspective, post-structuralist theories of Michel Foucault and a constructionist epistemology. The study participants were 19 midwifery students completing their final placement. Data were collected through individual in-depth interviews and participant observation, and analysed using the grounded theory analysis techniques of coding, constant comparative analysis and theoretical sampling, as well as situational maps. The analysis focused on social action and interaction and the operation of power in the students' environment. The social process in which the students were involved, as well as the actors and discourses that affected the students' competency development, were highlighted. The methodology allowed a thorough exploration of the students' experiences of achieving competency. However, some difficulties were encountered. One of the major issues related to the understanding and application of complex sociological theories that challenged positivist notions of truth and power. Furthermore, the mapping processes were complex. Despite these minor challenges, the authors recommend applying this methodology to other similar research projects.

A review of modern approaches to the hydrodynamic characterisation of polydisperse macromolecular systems in biotechnology.

PubMed

Gillis, Richard B; Rowe, Arthur J; Adams, Gary G; Harding, Stephen E

2014-10-01

This short review considers the range of modern techniques for the hydrodynamic characterisation of macromolecules - particularly large glycosylated systems used in the food, biopharma and healthcare industries. The range or polydispersity of molecular weights and conformations presents special challenges compared to proteins. The review is aimed, without going into any great theoretical or methodological depth, to help the Industrial Biotechnologist choose the appropriate methodology or combination of methodologies for providing the detail he/she needs for particular applications.

Using scenarios and personas to enhance the effectiveness of heuristic usability evaluations for older adults and their care team.

PubMed

Kneale, Laura; Mikles, Sean; Choi, Yong K; Thompson, Hilaire; Demiris, George

2017-09-01

Using heuristics to evaluate user experience is a common methodology for human-computer interaction studies. One challenge of this method is the inability to tailor results towards specific end-user needs. This manuscript reports on a method that uses validated scenarios and personas of older adults and care team members to enhance heuristics evaluations of the usability of commercially available personal health records for homebound older adults. Our work extends the Chisnell and Redish heuristic evaluation methodology by using a protocol that relies on multiple expert reviews of each system. It further standardizes the heuristic evaluation process through the incorporation of task-based scenarios. We were able to use the modified version of the Chisnell and Redish heuristic evaluation methodology to identify potential usability challenges of two commercially available personal health record systems. This allowed us to: (1) identify potential usability challenges for specific types of users, (2) describe improvements that would be valuable to all end-users of the system, and (3) better understand how the interactions of different users may vary within a single personal health record. The methodology described in this paper may help designers of consumer health information technology tools, such as personal health records, understand the needs of diverse end-user populations. Such methods may be particularly helpful when designing systems for populations that are difficult to recruit for end-user evaluations through traditional methods. Copyright © 2017 Elsevier Inc. All rights reserved.

Trend analyses in the health behaviour in school-aged children study: methodological considerations and recommendations.

PubMed

Schnohr, Christina W; Molcho, Michal; Rasmussen, Mette; Samdal, Oddrun; de Looze, Margreet; Levin, Kate; Roberts, Chris J; Ehlinger, Virginie; Krølner, Rikke; Dalmasso, Paola; Torsheim, Torbjørn

2015-04-01

This article presents the scope and development of the Health Behaviour in School-aged Children (HBSC) study, reviews trend papers published on international HBSC data up to 2012 and discusses the efforts made to produce reliable trend analyses. The major goal of this article is to present the statistical procedures and analytical strategies for upholding high data quality, as well as reflections from the authors of this article on how to produce reliable trends based on an international study of the magnitude of the HBSC study. HBSC is an international cross-sectional study collecting data from adolescents aged 11-15 years, on a broad variety of health determinants and health behaviours. A number of methodological challenges have stemmed from the growth of the HBSC-study, in particular given that the study has a focus on monitoring trends. Some of those challenges are considered. When analysing trends, researchers must be able to assess whether a change in prevalence is an expression of an actual change in the observed outcome, whether it is a result of methodological artefacts, or whether it is due to changes in the conceptualization of the outcome by the respondents. The article present recommendations to take a number of the considerations into account. The considerations imply methodological challenges, which are core issues in undertaking trend analyses. © The Author 2015. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

Uncertainty Reduction using Bayesian Inference and Sensitivity Analysis: A Sequential Approach to the NASA Langley Uncertainty Quantification Challenge

NASA Technical Reports Server (NTRS)

Sankararaman, Shankar

2016-01-01

This paper presents a computational framework for uncertainty characterization and propagation, and sensitivity analysis under the presence of aleatory and epistemic un- certainty, and develops a rigorous methodology for efficient refinement of epistemic un- certainty by identifying important epistemic variables that significantly affect the overall performance of an engineering system. The proposed methodology is illustrated using the NASA Langley Uncertainty Quantification Challenge (NASA-LUQC) problem that deals with uncertainty analysis of a generic transport model (GTM). First, Bayesian inference is used to infer subsystem-level epistemic quantities using the subsystem-level model and corresponding data. Second, tools of variance-based global sensitivity analysis are used to identify four important epistemic variables (this limitation specified in the NASA-LUQC is reflective of practical engineering situations where not all epistemic variables can be refined due to time/budget constraints) that significantly affect system-level performance. The most significant contribution of this paper is the development of the sequential refine- ment methodology, where epistemic variables for refinement are not identified all-at-once. Instead, only one variable is first identified, and then, Bayesian inference and global sensi- tivity calculations are repeated to identify the next important variable. This procedure is continued until all 4 variables are identified and the refinement in the system-level perfor- mance is computed. The advantages of the proposed sequential refinement methodology over the all-at-once uncertainty refinement approach are explained, and then applied to the NASA Langley Uncertainty Quantification Challenge problem.

A Visual Programming Methodology for Tactical Aircrew Scheduling and Other Applications

DTIC Science & Technology

1991-12-01

prgramming methodology and environment of a user-specific application remains with and is delivered as part of the application, then there is another factor...animation is useful, not only for scheduling applications, but as a general prgramming methodology. Of course, there are a number of improvements...possible using Excel because there is nothing to prevent access to cells. However, it is easy to imagine a spreadsheet which can support the

The Issues and Methodologies in Sustainability Assessment Tools for Higher Education Institutions: A Review of Recent Trends and Future Challenges

ERIC Educational Resources Information Center

Yarime, Masaru; Tanaka, Yuko

2012-01-01

Assessment tools influence incentives to higher education institutions by encouraging them to move towards sustainability. A review of 16 sustainability assessment tools was conducted to examine the recent trends in the issues and methodologies addressed in assessment tools quantitatively and qualitatively. The characteristics of the current…

On Teaching the History of California Spanish to HLL Using Siri: Methodology and Procedures

ERIC Educational Resources Information Center

Lamar Prieto, Covadonga

2016-01-01

This article reports results from a study in which two groups of college level students were exposed to interactions with Apple's Siri in order to foster dialogue about their dialectal features. In this paper, the methodology and procedural challenges behind one of the activities that the participants completed are studied. These activities had…

Investigating Historic Parcel Changes to Understand Land Use Trends: A Methodology and Application for the San Pedro River Watershed

EPA Science Inventory

Long-term land use and land cover change, and the associated impacts, pose critical challenges to sustaining healthy communities and ecosystems. In this study, a methodology was developed to use parcel data to evaluate land use trends in southeast Arizona’s San Pedro River Water...

e-Agriculture Prototype for Knowledge Facilitation among Tribal Farmers of North-East India: Innovations, Impact and Lessons

ERIC Educational Resources Information Center

Raj, Saravanan

2013-01-01

Purpose: This case study deals with the implementation methodology, innovations and lessons of the ICT initiative in providing agricultural extension services to the rural tribal farming community of North-East India. Methodology: This study documents the ICT project implementation challenges, impact among farmers and briefly indicates lessons of…

From Study to Work: Methodological Challenges of a Graduate Destination Survey in the Western Cape, South Africa

ERIC Educational Resources Information Center

du Toit, Jacques; Kraak, Andre; Favish, Judy; Fletcher, Lizelle

2014-01-01

Current literature proposes several strategies for improving response rates to student evaluation surveys. Graduate destination surveys pose the difficulty of tracing graduates years later when their contact details may have changed. This article discusses the methodology of one such a survey to maximise response rates. Compiling a sample frame…

How to Measure and Explain Achievement Change in Large-Scale Assessments: A Rejoinder

ERIC Educational Resources Information Center

Hickendorff, Marian; Heiser, Willem J.; van Putten, Cornelis M.; Verhelst, Norman D.

2009-01-01

In this rejoinder, we discuss substantive and methodological validity issues of large-scale assessments of trends in student achievement, commenting on the discussion paper by Van den Heuvel-Panhuizen, Robitzsch, Treffers, and Koller (2009). We focus on methodological challenges in deciding what to measure, how to measure it, and how to foster…

Developing a Customized Program Assessment Methodology for Assurance of Learning: A Case Study

ERIC Educational Resources Information Center

Baker, Hope; Brawley, Dorothy; Campbell, Jane; Capozzoli, Ernest; Malgeri, Linda; Roberts, Gary

2007-01-01

For most academic institutions, selecting and/or designing a Program Assessment methodology for Assurance of Learning is a challenging task. This paper describes the steps taken to establish goals, values and criteria driving this process for a College of Business. In this case analysis, we document the options we explored in finding the right…

Integration of PBL Methodologies into Online Learning Courses and Programs

ERIC Educational Resources Information Center

van Oostveen, Roland; Childs, Elizabeth; Flynn, Kathleen; Clarkson, Jessica

2014-01-01

Problem-based learning (PBL) challenges traditional views of teaching and learning as the learner determines, to a large extent with support from a skilled facilitator, what topics will be explored, to what depth and which processes will be used. This paper presents the implementation of problem-based learning methodologies in an online Bachelor's…

Forms of Voice: Exploring the Empowerment of Youth at the Intersection of Art and Action

ERIC Educational Resources Information Center

Greene, Stuart; Burke, Kevin; McKenna, Maria

2013-01-01

The authors utilize Photovoice methodology to engage in an examination of the possibilities of counternarrative through the photographs, oral accounts and drawings of three inner-city youths. In the process, this article seeks to expand upon and challenge prior uses of Photovoice methodologies and Critical Youth Engagement. The authors posit the…

Using the Photovoice Methodology to Increase Engagement and Sharpen Students' Analytical Skills Regarding Cultures, Lifestyles, and Markets Internationally

ERIC Educational Resources Information Center

Kelly, Kathleen; Lee, Seung Hwan; Bowen Ray, Heather; Kandaurova, Maria

2018-01-01

Barriers to cross-cultural instruction challenge even experienced educators and their students. To increase cross-cultural competence and bridge learning gaps, professors in two countries adapted the Photovoice methodology to develop shared visual vocabularies with students and unearth hidden assumptions. Results from an anonymous evaluation…

Action Research as a Congruent Methodology for Understanding Wikis: The Case of Wikiversity

ERIC Educational Resources Information Center

Lawler, Cormac

2008-01-01

It is proposed that action research is an appropriate methodology for studying wikis, and is akin to research "the wiki way". This proposal is contextualised within the case of Wikiversity, a project of the Wikimedia Foundation. A framework for a participative research project is outlined, and challenges and implications of such a…

Research Challenges Inherent in Determining Improvement in University Teaching

ERIC Educational Resources Information Center

Devlin, Marcia

2008-01-01

Using a recent study that examined the effectiveness of a particular approach to improving individual university teaching as a case study, this paper examines some of the challenges inherent in educational research, particularly research examining the effects of interventions to improve teaching. Aspects of the research design and methodology and…

Philippine Classroom Teachers as Researchers: Teachers' Perceptions, Motivations, and Challenges

ERIC Educational Resources Information Center

Ulla, Mark B.; Barrera, Kenneth Ian B.; Acompanado, Meller M.

2017-01-01

This study explores teachers' perceptions and motivations, challenges, and needs of 50 teachers in Agusan del Norte, Philippines with regards to doing research. Methodologies used were survey questionnaire, and group and individual interviews. Findings revealed that teacher-respondents had a positive perceptions towards doing research and its…

Integrated modeling systems to assess exposure and toxicity of chemicals in support of aquatic ecological risk assessment of methodologically challenging chemicals

EPA Science Inventory

From an exposure assessment perspective, persistent, bioaccumulative and toxic chemicals (PBTs) are some of the most challenging chemicals facing environmental decision makers today. Due to their general physico-chemical properties [e.g., high octanol-water partition coefficien...

"That's Not Quite the Way We See It": The Epistemological Challenge of Visual Data

ERIC Educational Resources Information Center

Wall, Kate; Higgins, Steve; Hall, Elaine; Woolner, Pam

2013-01-01

In research textbooks, and much of the research practice, they describe, qualitative processes and interpretivist epistemologies tend to dominate visual methodology. This article challenges the assumptions behind this dominance. Using exemplification from three existing visual data sets produced through one large education research project, this…

Intergenerational Learning and Knowledge Transfer--Challenges and Opportunities

ERIC Educational Resources Information Center

Rupcic, Nataša

2018-01-01

Purpose: The purpose of this paper is to highlight challenges and opportunities that surround the process of intergenerational learning and knowledge transfer. Several options in this regard have been discussed from the managerial and employee perspective. Design/methodology/approach: The systems approach has been implemented to identify options…

Sustainability: Necessity for a Prosperous Society

ERIC Educational Resources Information Center

Fokkema, Jacob; Jansen, Leo; Mulder, Karel

2005-01-01

Purpose--To present the challenge of sustainable development, the way in which technology can address that challenge and the task of engineering education to train engineers for it. Design/methodology/approach--The paper describes briefly the history of the environmental and sustainability discourse in The Netherlands, as a densely populated…

A Zone for Deliberation? Methodological Challenges in Fields of Political Unrest

ERIC Educational Resources Information Center

Westrheim, Kariane; Lillejord, Solvi

2007-01-01

This article outlines certain problems and challenges facing the qualitative researcher who enters fields that are either extremely difficult to access or potentially hostile towards outsiders. Problems and dilemmas in such contexts are highlighted by reference to fieldwork research among PKK (Kurdistan Worker's Party) guerrillas in North…

Raising Concerns about Sharing and Reusing Large-Scale Mathematics Classroom Observation Video Data

ERIC Educational Resources Information Center

Ing, Marsha; Samkian, Artineh

2018-01-01

There are great opportunities and challenges to sharing large-scale mathematics classroom observation data. This Research Commentary describes the methodological opportunities and challenges and provides a specific example from a mathematics education research project to illustrate how the research questions and framework drove observational…

Characteristic Interviews, Different Strategies: Methodological Challenges in Qualitative Interviewing among Respondents with Mild Intellectual Disabilities

ERIC Educational Resources Information Center

Sigstad, Hanne Marie Høybråten

2014-01-01

Conducting qualitative research interviews among individuals with intellectual disabilities, including cognitive limitations and difficulties in communication, presents particular research challenges. One question is whether the difficulties that informants encounter affect interviews to such an extent that the validity of the results is weakened.…