Comparison of methodological quality of positive versus negative comparative studies published in Indian medical journals: a systematic review

PubMed Central

Charan, Jaykaran; Chaudhari, Mayur; Jackson, Ryan; Mhaskar, Rahul; Reljic, Tea; Kumar, Ambuj

2015-01-01

Objectives Published negative studies should have the same rigour of methodological quality as studies with positive findings. However, the methodological quality of negative versus positive studies is not known. The objective was to assess the reported methodological quality of positive versus negative studies published in Indian medical journals. Design A systematic review (SR) was performed of all comparative studies published in Indian medical journals with a clinical science focus and impact factor >1 between 2011 and 2013. The methodological quality of randomised controlled trials (RCTs) was assessed using the Cochrane risk of bias tool, and the Newcastle-Ottawa scale for observational studies. The results were considered positive if the primary outcome was statistically significant and negative otherwise. When the primary outcome was not specified, we used data on the first outcome reported in the history followed by the results section. Differences in various methodological quality domains between positive versus negative studies were assessed by Fisher's exact test. Results Seven journals with 259 comparative studies were included in this SR. 24% (63/259) were RCTs, 24% (63/259) cohort studies, and 49% (128/259) case–control studies. 53% (137/259) of studies explicitly reported the primary outcome. Five studies did not report sufficient data to enable us to determine if results were positive or negative. Statistical significance was determined by p value in 78.3% (199/254), CI in 2.8% (7/254), both p value and CI in 11.8% (30/254), and only descriptive in 6.3% (16/254) of studies. The overall methodological quality was poor and no statistically significant differences between reporting of methodological quality were detected between studies with positive versus negative findings. Conclusions There was no difference in the reported methodological quality of positive versus negative studies. However, the uneven reporting of positive versus negative studies (72% vs 28%) indicates a publication bias in Indian medical journals with an impact factor of >1. PMID:26109118

Turbofan engine control system design using the LQG/LTR methodology

NASA Technical Reports Server (NTRS)

Garg, Sanjay

1989-01-01

Application of the linear-quadratic-Gaussian with loop-transfer-recovery methodology to design of a control system for a simplified turbofan engine model is considered. The importance of properly scaling the plant to achieve the desired target feedback loop is emphasized. The steps involved in the application of the methodology are discussed via an example, and evaluation results are presented for a reduced-order compensator. The effect of scaling the plant on the stability robustness evaluation of the closed-loop system is studied in detail.

Turbofan engine control system design using the LQG/LTR methodology

NASA Technical Reports Server (NTRS)

Garg, Sanjay

1989-01-01

Application of the Linear-Quadratic-Gaussian with Loop-Transfer-Recovery methodology to design of a control system for a simplified turbofan engine model is considered. The importance of properly scaling the plant to achieve the desired Target-Feedback-Loop is emphasized. The steps involved in the application of the methodology are discussed via an example, and evaluation results are presented for a reduced-order compensator. The effect of scaling the plant on the stability robustness evaluation of the closed-loop system is studied in detail.

Published methodological quality of randomized controlled trials does not reflect the actual quality assessed in protocols.

PubMed

Mhaskar, Rahul; Djulbegovic, Benjamin; Magazin, Anja; Soares, Heloisa P; Kumar, Ambuj

2012-06-01

To assess whether the reported methodological quality of randomized controlled trials (RCTs) reflects the actual methodological quality and to evaluate the association of effect size (ES) and sample size with methodological quality. Systematic review. This is a retrospective analysis of all consecutive phase III RCTs published by eight National Cancer Institute Cooperative Groups up to 2006. Data were extracted from protocols (actual quality) and publications (reported quality) for each study. Four hundred twenty-nine RCTs met the inclusion criteria. Overall reporting of methodological quality was poor and did not reflect the actual high methodological quality of RCTs. The results showed no association between sample size and actual methodological quality of a trial. Poor reporting of allocation concealment and blinding exaggerated the ES by 6% (ratio of hazard ratio [RHR]: 0.94; 95% confidence interval [CI]: 0.88, 0.99) and 24% (RHR: 1.24; 95% CI: 1.05, 1.43), respectively. However, actual quality assessment showed no association between ES and methodological quality. The largest study to date shows that poor quality of reporting does not reflect the actual high methodological quality. Assessment of the impact of quality on the ES based on reported quality can produce misleading results. Copyright © 2012 Elsevier Inc. All rights reserved.

Critical Thinking: Comparing Instructional Methodologies in a Senior-Year Learning Community

ERIC Educational Resources Information Center

Zelizer, Deborah A.

2013-01-01

This quasi-experimental, nonequivalent control group study compared the impact of Ennis's (1989) mixed instructional methodology to the immersion methodology on the development of critical thinking in a multicultural, undergraduate senior-year learning community. A convenience sample of students (n =171) were selected from four sections of a…

Comparison of methodological quality of positive versus negative comparative studies published in Indian medical journals: a systematic review.

PubMed

Charan, Jaykaran; Chaudhari, Mayur; Jackson, Ryan; Mhaskar, Rahul; Reljic, Tea; Kumar, Ambuj

2015-06-24

Published negative studies should have the same rigour of methodological quality as studies with positive findings. However, the methodological quality of negative versus positive studies is not known. The objective was to assess the reported methodological quality of positive versus negative studies published in Indian medical journals. A systematic review (SR) was performed of all comparative studies published in Indian medical journals with a clinical science focus and impact factor >1 between 2011 and 2013. The methodological quality of randomised controlled trials (RCTs) was assessed using the Cochrane risk of bias tool, and the Newcastle-Ottawa scale for observational studies. The results were considered positive if the primary outcome was statistically significant and negative otherwise. When the primary outcome was not specified, we used data on the first outcome reported in the history followed by the results section. Differences in various methodological quality domains between positive versus negative studies were assessed by Fisher's exact test. Seven journals with 259 comparative studies were included in this SR. 24% (63/259) were RCTs, 24% (63/259) cohort studies, and 49% (128/259) case-control studies. 53% (137/259) of studies explicitly reported the primary outcome. Five studies did not report sufficient data to enable us to determine if results were positive or negative. Statistical significance was determined by p value in 78.3% (199/254), CI in 2.8% (7/254), both p value and CI in 11.8% (30/254), and only descriptive in 6.3% (16/254) of studies. The overall methodological quality was poor and no statistically significant differences between reporting of methodological quality were detected between studies with positive versus negative findings. There was no difference in the reported methodological quality of positive versus negative studies. However, the uneven reporting of positive versus negative studies (72% vs 28%) indicates a publication bias in Indian medical journals with an impact factor of >1. 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.

Application of an Integrated Methodology for Propulsion and Airframe Control Design to a STOVL Aircraft

NASA Technical Reports Server (NTRS)

Garg, Sanjay; Mattern, Duane

1994-01-01

An advanced methodology for integrated flight propulsion control (IFPC) design for future aircraft, which will use propulsion system generated forces and moments for enhanced maneuver capabilities, is briefly described. This methodology has the potential to address in a systematic manner the coupling between the airframe and the propulsion subsystems typical of such enhanced maneuverability aircraft. Application of the methodology to a short take-off vertical landing (STOVL) aircraft in the landing approach to hover transition flight phase is presented with brief description of the various steps in the IFPC design methodology. The details of the individual steps have been described in previous publications and the objective of this paper is to focus on how the components of the control system designed at each step integrate into the overall IFPC system. The full nonlinear IFPC system was evaluated extensively in nonreal-time simulations as well as piloted simulations. Results from the nonreal-time evaluations are presented in this paper. Lessons learned from this application study are summarized in terms of areas of potential improvements in the STOVL IFPC design as well as identification of technology development areas to enhance the applicability of the proposed design methodology.

Social cognition interventions for people with schizophrenia: a systematic review focussing on methodological quality and intervention modality.

PubMed

Grant, Nina; Lawrence, Megan; Preti, Antonio; Wykes, Til; Cella, Matteo

2017-08-01

People with a diagnosis of schizophrenia have significant social and functional difficulties. Social cognition was found to influences these outcomes and in recent years interventions targeting this domain were developed. This paper reviews the existing literature on social cognition interventions for people with a diagnosis of schizophrenia focussing on: i) comparing focussed (i.e. targeting only one social cognitive domain) and global interventions and ii) studies methodological quality. Systematic search was conducted on PubMed and PsycInfo. Studies were included if they were randomised control trials, participants had a diagnosis of schizophrenia or schizoaffective disorder, and the intervention targeted at least one out of four social cognition domains (i.e. theory of mind, affect recognition, social perception and attribution bias). All papers were assessed for methodological quality. Information on the intervention, control condition, study methodology and the main findings from each study were extracted and critically summarised. Data from 32 studies fulfilled the inclusion criteria, considering a total of 1440 participants. Taking part in social cognition interventions produced significant improvements in theory of mind and affect recognition compared to both passive and active control conditions. Results were less clear for social perception and attributional bias. Focussed and global interventions had similar results on outcomes. Overall study methodological quality was modest. There was very limited evidence showing that social cognitive intervention result in functional outcome improvement. The evidence considered suggests that social cognition interventions may be a valuable approach for people with a diagnosis of schizophrenia. However, evidence quality is limited by measure heterogeneity, modest study methodology and short follow-up periods. The findings point to a number of recommendations for future research, including measurement standardisation, appropriately powered studies and investigation of the impact of social cognition improvements on functioning problems. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Design Of Combined Stochastic Feedforward/Feedback Control

NASA Technical Reports Server (NTRS)

Halyo, Nesim

1989-01-01

Methodology accommodates variety of control structures and design techniques. In methodology for combined stochastic feedforward/feedback control, main objectives of feedforward and feedback control laws seen clearly. Inclusion of error-integral feedback, dynamic compensation, rate-command control structure, and like integral element of methodology. Another advantage of methodology flexibility to develop variety of techniques for design of feedback control with arbitrary structures to obtain feedback controller: includes stochastic output feedback, multiconfiguration control, decentralized control, or frequency and classical control methods. Control modes of system include capture and tracking of localizer and glideslope, crab, decrab, and flare. By use of recommended incremental implementation, control laws simulated on digital computer and connected with nonlinear digital simulation of aircraft and its systems.

Application of quality improvement analytic methodology in emergency medicine research: A comparative evaluation.

PubMed

Harries, Bruce; Filiatrault, Lyne; Abu-Laban, Riyad B

2018-05-30

Quality improvement (QI) analytic methodology is rarely encountered in the emergency medicine literature. We sought to comparatively apply QI design and analysis techniques to an existing data set, and discuss these techniques as an alternative to standard research methodology for evaluating a change in a process of care. We used data from a previously published randomized controlled trial on triage-nurse initiated radiography using the Ottawa ankle rules (OAR). QI analytic tools were applied to the data set from this study and evaluated comparatively against the original standard research methodology. The original study concluded that triage nurse-initiated radiographs led to a statistically significant decrease in mean emergency department length of stay. Using QI analytic methodology, we applied control charts and interpreted the results using established methods that preserved the time sequence of the data. This analysis found a compelling signal of a positive treatment effect that would have been identified after the enrolment of 58% of the original study sample, and in the 6th month of this 11-month study. Our comparative analysis demonstrates some of the potential benefits of QI analytic methodology. We found that had this approach been used in the original study, insights regarding the benefits of nurse-initiated radiography using the OAR would have been achieved earlier, and thus potentially at a lower cost. In situations where the overarching aim is to accelerate implementation of practice improvement to benefit future patients, we believe that increased consideration should be given to the use of QI analytic methodology.

Verification methodology for fault-tolerant, fail-safe computers applied to maglev control computer systems. Final report, July 1991-May 1993

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

Lala, J.H.; Nagle, G.A.; Harper, R.E.

1993-05-01

The Maglev control computer system should be designed to verifiably possess high reliability and safety as well as high availability to make Maglev a dependable and attractive transportation alternative to the public. A Maglev control computer system has been designed using a design-for-validation methodology developed earlier under NASA and SDIO sponsorship for real-time aerospace applications. The present study starts by defining the maglev mission scenario and ends with the definition of a maglev control computer architecture. Key intermediate steps included definitions of functional and dependability requirements, synthesis of two candidate architectures, development of qualitative and quantitative evaluation criteria, and analyticalmore » modeling of the dependability characteristics of the two architectures. Finally, the applicability of the design-for-validation methodology was also illustrated by applying it to the German Transrapid TR07 maglev control system.« less

The RAAF Logistics Study. Volume 4,

DTIC Science & Technology

1986-10-01

Use of Issue-Based Root Definitions Application of Soft Systems Methodology to 27 Information Systems Analysis Conclusion 30 LIST OF ABBREVIATIONS 58 k...Management Control Systems’, Journal of Applied Systems Analysis, Volume 6, 1979, pages 51 to 67. 5. The soft systems methodology was developed to tackle...the soft systems methodology has many advantages whi-h recmmenrl it to this type of study area, it does not mcklel the timo ev, lut i, n :-f a system

Methodological studies on the VVER-440 control assembly calculations

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

Hordosy, G.; Kereszturi, A.; Maraczy, C.

1995-12-31

The control assembly regions of VVER-440 reactors are represented by 2-group albedo matrices in the global calculations of the KARATE code system. Some methodological aspects of calculating albedo matrices with the COLA transport code are presented. Illustrations are given how these matrices depend on the relevant parameters describing the boron steel and steel regions of the control assemblies. The calculation of the response matrix for a node consisting of two parts filled with different materials is discussed.

Assessing validity of observational intervention studies - the Benchmarking Controlled Trials.

PubMed

Malmivaara, Antti

2016-09-01

Benchmarking Controlled Trial (BCT) is a concept which covers all observational studies aiming to assess impact of interventions or health care system features to patients and populations. To create and pilot test a checklist for appraising methodological validity of a BCT. The checklist was created by extracting the most essential elements from the comprehensive set of criteria in the previous paper on BCTs. Also checklists and scientific papers on observational studies and respective systematic reviews were utilized. Ten BCTs published in the Lancet and in the New England Journal of Medicine were used to assess feasibility of the created checklist. The appraised studies seem to have several methodological limitations, some of which could be avoided in planning, conducting and reporting phases of the studies. The checklist can be used for planning, conducting, reporting, reviewing, and critical reading of observational intervention studies. However, the piloted checklist should be validated in further studies. Key messages Benchmarking Controlled Trial (BCT) is a concept which covers all observational studies aiming to assess impact of interventions or health care system features to patients and populations. This paper presents a checklist for appraising methodological validity of BCTs and pilot-tests the checklist with ten BCTs published in leading medical journals. The appraised studies seem to have several methodological limitations, some of which could be avoided in planning, conducting and reporting phases of the studies. The checklist can be used for planning, conducting, reporting, reviewing, and critical reading of observational intervention studies.

Controlled Trials in Children: Quantity, Methodological Quality and Descriptive Characteristics of Pediatric Controlled Trials Published 1948-2006

PubMed Central

Thomson, Denise; Hartling, Lisa; Cohen, Eyal; Vandermeer, Ben; Tjosvold, Lisa; Klassen, Terry P.

2010-01-01

Background The objective of this study was to describe randomized controlled trials (RCTs) and controlled clinical trials (CCTs) in child health published between 1948 and 2006, in terms of quantity, methodological quality, and publication and trial characteristics. We used the Trials Register of the Cochrane Child Health Field for overall trends and a sample from this to explore trial characteristics in more detail. Methodology/Principal Findings We extracted descriptive data on a random sample of 578 trials. Ninety-six percent of the trials were published in English; the percentage of child-only trials was 90.5%. The most frequent diagnostic categories were infectious diseases (13.2%), behavioural and psychiatric disorders (11.6%), neonatal critical care (11.4%), respiratory disorders (8.9%), non-critical neonatology (7.9%), and anaesthesia (6.5%). There were significantly fewer child-only studies (i.e., more mixed child and adult studies) over time (P = 0.0460). The proportion of RCTs to CCTs increased significantly over time (P<0.0001), as did the proportion of multicentre trials (P = 0.002). Significant increases over time were found in methodological quality (Jadad score) (P<0.0001), the proportion of double-blind studies (P<0.0001), and studies with adequate allocation concealment (P<0.0001). Additionally, we found an improvement in reporting over time: adequate description of withdrawals and losses to follow-up (P<0.0001), sample size calculations (P<0.0001), and intention-to-treat analysis (P<0.0001). However, many trials still do not describe their level of blinding, and allocation concealment was inadequately reported in the majority of studies across the entire time period. The proportion of studies with industry funding decreased slightly over time (P = 0.003), and these studies were more likely to report positive conclusions (P = 0.028). Conclusions/Significance The quantity and quality of pediatric controlled trials has increased over time; however, much work remains to be done, particularly in improving methodological issues around conduct and reporting of trials. PMID:20927344

Design, methodological issues and participation in a multiple sclerosis case-control study.

PubMed

Williamson, D M; Marrie, R A; Ashley-Koch, A; Schiffer, R; Trottier, J; Wagner, L

2012-09-01

This study was conducted to determine whether the risk of developing multiple sclerosis (MS) was associated with certain environmental exposures or genetic factors previously reported to influence MS risk. This paper describes the methodological issues, study design and characteristics of the study population. Individuals with definite MS were identified from a prevalence study conducted in three geographic areas. The target number of cases was not reached, so an additional study area was added. Identifying clinic controls was inefficient, so controls were recruited using random digit dialing. All study participants completed a detailed questionnaire regarding environmental exposures using computer-assisted telephone interviewing, and blood was collected for genetic analysis. In total, 276 cases and 590 controls participated, but participation rates were low, ranging from 28.4% to 38.9%. Only one-third (33.6%) of individuals identified in the prevalence study agreed to participate in the case-control study. Cases were more likely to be non-Hispanic white and older than their source populations as identified in the preceding prevalence study (P < 0.05). Most participants provided a blood sample for genotyping (91%; n = 789). Epidemiological studies play a key role in identifying genetic and environmental factors that are associated with complex diseases like MS. Methodological issues arise in every study, and investigators need to be able to detect, respond to and correct problems in a timely and scientifically valid manner. © 2011 John Wiley & Sons A/S.

The efficacy of attentional distraction and sensory monitoring in chronic pain patients: A meta-analysis.

PubMed

Van Ryckeghem, Dimitri Ml; Van Damme, Stefaan; Eccleston, Christopher; Crombez, Geert

2018-02-01

Attentional strategies, such as distraction and sensory monitoring, are often offered to reduce pain and pain-related distress. However, evidence for their efficacy in chronic pain patients is equivocal. We report a meta-analysis on the efficacy of distraction and sensory monitoring in chronic pain patients, and explore possible methodological and theoretical moderators. The scientific literature was searched for relevant articles, which were coded for methodological quality and several theoretical and methodological moderator variables. Only 10 articles fulfilled the search criteria. Eight studies allowed us to compare distraction with a control condition, two studies to compare sensory monitoring with a control condition, and four studies to compare the effect of distraction with the effect of sensory monitoring. Overall, results indicate that distraction did not differ from control in altering pain experience (k=8; Hedges' g=0.10, ns) and distress (k=2; Hedges' g=0.549). Sensory monitoring did also not alter pain experience (k=2; Hedges' g=-0.21, ns) and distress (k=1; Hedges' g=-0.191, ns). We found no evidence to support the superiority of distraction or sensory monitoring in altering pain compared to control conditions. We offer guidance for future theory-driven research to investigate distraction and sensory monitoring in this largely unexplored field, albeit one replete with methodological difficulties. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multirate flutter suppression system design for the Benchmark Active Controls Technology Wing

NASA Technical Reports Server (NTRS)

Berg, Martin C.; Mason, Gregory S.

1994-01-01

To study the effectiveness of various control system design methodologies, the NASA Langley Research Center initiated the Benchmark Active Controls Project. In this project, the various methodologies will be applied to design a flutter suppression system for the Benchmark Active Controls Technology (BACT) Wing (also called the PAPA wing). Eventually, the designs will be implemented in hardware and tested on the BACT wing in a wind tunnel. This report describes a project at the University of Washington to design a multirate flutter suppression system for the BACT wing. The objective of the project was two fold. First, to develop a methodology for designing robust multirate compensators, and second, to demonstrate the methodology by applying it to the design of a multirate flutter suppression system for the BACT wing. The contributions of this project are (1) development of an algorithm for synthesizing robust low order multirate control laws (the algorithm is capable of synthesizing a single compensator which stabilizes both the nominal plant and multiple plant perturbations; (2) development of a multirate design methodology, and supporting software, for modeling, analyzing and synthesizing multirate compensators; and (3) design of a multirate flutter suppression system for NASA's BACT wing which satisfies the specified design criteria. This report describes each of these contributions in detail. Section 2.0 discusses our design methodology. Section 3.0 details the results of our multirate flutter suppression system design for the BACT wing. Finally, Section 4.0 presents our conclusions and suggestions for future research. The body of the report focuses primarily on the results. The associated theoretical background appears in the three technical papers that are included as Attachments 1-3. Attachment 4 is a user's manual for the software that is key to our design methodology.

Robust nonlinear variable selective control for networked systems

NASA Astrophysics Data System (ADS)

Rahmani, Behrooz

2016-10-01

This paper is concerned with the networked control of a class of uncertain nonlinear systems. In this way, Takagi-Sugeno (T-S) fuzzy modelling is used to extend the previously proposed variable selective control (VSC) methodology to nonlinear systems. This extension is based upon the decomposition of the nonlinear system to a set of fuzzy-blended locally linearised subsystems and further application of the VSC methodology to each subsystem. To increase the applicability of the T-S approach for uncertain nonlinear networked control systems, this study considers the asynchronous premise variables in the plant and the controller, and then introduces a robust stability analysis and control synthesis. The resulting optimal switching-fuzzy controller provides a minimum guaranteed cost on an H2 performance index. Simulation studies on three nonlinear benchmark problems demonstrate the effectiveness of the proposed method.

Control-Structure-Interaction (CSI) technologies and trends to future NASA missions

NASA Technical Reports Server (NTRS)

1990-01-01

Control-structure-interaction (CSI) issues which are relevant for future NASA missions are reviewed. This goal was achieved by: (1) reviewing large space structures (LSS) technologies to provide a background and survey of the current state of the art (SOA); (2) analytically studying a focus mission to identify opportunities where CSI technology may be applied to enhance or enable future NASA spacecraft; and (3) expanding a portion of the focus mission, the large antenna, to provide in-depth trade studies, scaling laws, and methodologies which may be applied to other NASA missions. Several sections are presented. Section 1 defines CSI issues and presents an overview of the relevant modeling and control issues for LLS. Section 2 presents the results of the three phases of the CSI study. Section 2.1 gives the results of a CSI study conducted with the Geostationary Platform (Geoplat) as the focus mission. Section 2.2 contains an overview of the CSI control design methodology available in the technical community. Included is a survey of the CSI ground-based experiments which were conducted to verify theoretical performance predictions. Section 2.3 presents and demonstrates a new CSI scaling law methodology for assessing potential CSI with large antenna systems.

Medication safety research by observational study design.

PubMed

Lao, Kim S J; Chui, Celine S L; Man, Kenneth K C; Lau, Wallis C Y; Chan, Esther W; Wong, Ian C K

2016-06-01

Observational studies have been recognised to be essential for investigating the safety profile of medications. Numerous observational studies have been conducted on the platform of large population databases, which provide adequate sample size and follow-up length to detect infrequent and/or delayed clinical outcomes. Cohort and case-control are well-accepted traditional methodologies for hypothesis testing, while within-individual study designs are developing and evolving, addressing previous known methodological limitations to reduce confounding and bias. Respective examples of observational studies of different study designs using medical databases are shown. Methodology characteristics, study assumptions, strengths and weaknesses of each method are discussed in this review.

A design methodology for nonlinear systems containing parameter uncertainty: Application to nonlinear controller design

NASA Technical Reports Server (NTRS)

Young, G.

1982-01-01

A design methodology capable of dealing with nonlinear systems, such as a controlled ecological life support system (CELSS), containing parameter uncertainty is discussed. The methodology was applied to the design of discrete time nonlinear controllers. The nonlinear controllers can be used to control either linear or nonlinear systems. Several controller strategies are presented to illustrate the design procedure.

Assessing validity of observational intervention studies – the Benchmarking Controlled Trials

PubMed Central

Malmivaara, Antti

2016-01-01

Abstract Background: Benchmarking Controlled Trial (BCT) is a concept which covers all observational studies aiming to assess impact of interventions or health care system features to patients and populations. Aims: To create and pilot test a checklist for appraising methodological validity of a BCT. Methods: The checklist was created by extracting the most essential elements from the comprehensive set of criteria in the previous paper on BCTs. Also checklists and scientific papers on observational studies and respective systematic reviews were utilized. Ten BCTs published in the Lancet and in the New England Journal of Medicine were used to assess feasibility of the created checklist. Results: The appraised studies seem to have several methodological limitations, some of which could be avoided in planning, conducting and reporting phases of the studies. Conclusions: The checklist can be used for planning, conducting, reporting, reviewing, and critical reading of observational intervention studies. However, the piloted checklist should be validated in further studies.Key messagesBenchmarking Controlled Trial (BCT) is a concept which covers all observational studies aiming to assess impact of interventions or health care system features to patients and populations.This paper presents a checklist for appraising methodological validity of BCTs and pilot-tests the checklist with ten BCTs published in leading medical journals. The appraised studies seem to have several methodological limitations, some of which could be avoided in planning, conducting and reporting phases of the studies.The checklist can be used for planning, conducting, reporting, reviewing, and critical reading of observational intervention studies. PMID:27238631

Quality in the Basic Grant Delivery System: Volume 3, Methodology.

ERIC Educational Resources Information Center

Advanced Technology, Inc., McLean, VA.

The research methodology of a study to assess 1980-1981 award accuracy of the Basic Educational Opportunity Grants (BEOG), or Pell grants, is described. The study is the first stage of a three-stage quality control project. During the spring of 1981 a nationally representative sample of 305 public, private, and proprietary institutions was…

A Ten Year Study of Salary Differential by Sex through a Regression Methodology.

ERIC Educational Resources Information Center

Williams, John Delane; And Others

A 10-year study of salary differential by sex was undertaken at the University of North Dakota using a multiple regression methodology, with rank, discipline, degree, years in department, years in current rank, and sex as predictors. The sex variable evidenced lower salaries for women when controlling for the other variables throughout the study…

An autonomous satellite architecture integrating deliberative reasoning and behavioural intelligence

NASA Technical Reports Server (NTRS)

Lindley, Craig A.

1993-01-01

This paper describes a method for the design of autonomous spacecraft, based upon behavioral approaches to intelligent robotics. First, a number of previous spacecraft automation projects are reviewed. A methodology for the design of autonomous spacecraft is then presented, drawing upon both the European Space Agency technological center (ESTEC) automation and robotics methodology and the subsumption architecture for autonomous robots. A layered competency model for autonomous orbital spacecraft is proposed. A simple example of low level competencies and their interaction is presented in order to illustrate the methodology. Finally, the general principles adopted for the control hardware design of the AUSTRALIS-1 spacecraft are described. This system will provide an orbital experimental platform for spacecraft autonomy studies, supporting the exploration of different logical control models, different computational metaphors within the behavioral control framework, and different mappings from the logical control model to its physical implementation.

Controlled trials in children: quantity, methodological quality and descriptive characteristics of pediatric controlled trials published 1948-2006.

PubMed

Thomson, Denise; Hartling, Lisa; Cohen, Eyal; Vandermeer, Ben; Tjosvold, Lisa; Klassen, Terry P

2010-09-30

The objective of this study was to describe randomized controlled trials (RCTs) and controlled clinical trials (CCTs) in child health published between 1948 and 2006, in terms of quantity, methodological quality, and publication and trial characteristics. We used the Trials Register of the Cochrane Child Health Field for overall trends and a sample from this to explore trial characteristics in more detail. We extracted descriptive data on a random sample of 578 trials. Ninety-six percent of the trials were published in English; the percentage of child-only trials was 90.5%. The most frequent diagnostic categories were infectious diseases (13.2%), behavioural and psychiatric disorders (11.6%), neonatal critical care (11.4%), respiratory disorders (8.9%), non-critical neonatology (7.9%), and anaesthesia (6.5%). There were significantly fewer child-only studies (i.e., more mixed child and adult studies) over time (P = 0.0460). The proportion of RCTs to CCTs increased significantly over time (P<0.0001), as did the proportion of multicentre trials (P = 0.002). Significant increases over time were found in methodological quality (Jadad score) (P<0.0001), the proportion of double-blind studies (P<0.0001), and studies with adequate allocation concealment (P<0.0001). Additionally, we found an improvement in reporting over time: adequate description of withdrawals and losses to follow-up (P<0.0001), sample size calculations (P<0.0001), and intention-to-treat analysis (P<0.0001). However, many trials still do not describe their level of blinding, and allocation concealment was inadequately reported in the majority of studies across the entire time period. The proportion of studies with industry funding decreased slightly over time (P = 0.003), and these studies were more likely to report positive conclusions (P = 0.028). The quantity and quality of pediatric controlled trials has increased over time; however, much work remains to be done, particularly in improving methodological issues around conduct and reporting of trials.

Graded activation of the intrinsic laryngeal muscles for vocal fold posturing

PubMed Central

Chhetri, Dinesh K.; Neubauer, Juergen; Berry, David A.

2010-01-01

Previous investigations using in vivo models to study the role of intrinsic laryngeal muscles in phonation have used neuromuscular stimulation to study voice parameters. However, these studies used coarse stimulation techniques using limited levels of neuromuscular stimulation. In the current investigation, a technique for fine control of laryngeal posturing was developed using graded stimulation of the laryngeal nerves. Vocal fold strain history to graded stimulation and a methodology for establishing symmetric laryngeal activation is presented. This methodology has immediate applications for the study of laryngeal paralysis and paresis, as well as general questions of neuromuscular control of the larynx. PMID:20369979

Systematic review of the application of quality improvement methodologies from the manufacturing industry to surgical healthcare.

PubMed

Nicolay, C R; Purkayastha, S; Greenhalgh, A; Benn, J; Chaturvedi, S; Phillips, N; Darzi, A

2012-03-01

The demand for the highest-quality patient care coupled with pressure on funding has led to the increasing use of quality improvement (QI) methodologies from the manufacturing industry. The aim of this systematic review was to identify and evaluate the application and effectiveness of these QI methodologies to the field of surgery. MEDLINE, the Cochrane Database, Allied and Complementary Medicine Database, British Nursing Index, Cumulative Index to Nursing and Allied Health Literature, Embase, Health Business(™) Elite, the Health Management Information Consortium and PsycINFO(®) were searched according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Empirical studies were included that implemented a described QI methodology to surgical care and analysed a named outcome statistically. Some 34 of 1595 articles identified met the inclusion criteria after consensus from two independent investigators. Nine studies described continuous quality improvement (CQI), five Six Sigma, five total quality management (TQM), five plan-do-study-act (PDSA) or plan-do-check-act (PDCA) cycles, five statistical process control (SPC) or statistical quality control (SQC), four Lean and one Lean Six Sigma; 20 of the studies were undertaken in the USA. The most common aims were to reduce complications or improve outcomes (11), to reduce infection (7), and to reduce theatre delays (7). There was one randomized controlled trial. QI methodologies from industry can have significant effects on improving surgical care, from reducing infection rates to increasing operating room efficiency. The evidence is generally of suboptimal quality, and rigorous randomized multicentre studies are needed to bring evidence-based management into the same league as evidence-based medicine. Copyright © 2011 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.

Control group design: enhancing rigor in research of mind-body therapies for depression.

PubMed

Kinser, Patricia Anne; Robins, Jo Lynne

2013-01-01

Although a growing body of research suggests that mind-body therapies may be appropriate to integrate into the treatment of depression, studies consistently lack methodological sophistication particularly in the area of control groups. In order to better understand the relationship between control group selection and methodological rigor, we provide a brief review of the literature on control group design in yoga and tai chi studies for depression, and we discuss challenges we have faced in the design of control groups for our recent clinical trials of these mind-body complementary therapies for women with depression. To address the multiple challenges of research about mind-body therapies, we suggest that researchers should consider 4 key questions: whether the study design matches the research question; whether the control group addresses performance, expectation, and detection bias; whether the control group is ethical, feasible, and attractive; and whether the control group is designed to adequately control for nonspecific intervention effects. Based on these questions, we provide specific recommendations about control group design with the goal of minimizing bias and maximizing validity in future research.

Control Group Design: Enhancing Rigor in Research of Mind-Body Therapies for Depression

PubMed Central

Kinser, Patricia Anne; Robins, Jo Lynne

2013-01-01

Although a growing body of research suggests that mind-body therapies may be appropriate to integrate into the treatment of depression, studies consistently lack methodological sophistication particularly in the area of control groups. In order to better understand the relationship between control group selection and methodological rigor, we provide a brief review of the literature on control group design in yoga and tai chi studies for depression, and we discuss challenges we have faced in the design of control groups for our recent clinical trials of these mind-body complementary therapies for women with depression. To address the multiple challenges of research about mind-body therapies, we suggest that researchers should consider 4 key questions: whether the study design matches the research question; whether the control group addresses performance, expectation, and detection bias; whether the control group is ethical, feasible, and attractive; and whether the control group is designed to adequately control for nonspecific intervention effects. Based on these questions, we provide specific recommendations about control group design with the goal of minimizing bias and maximizing validity in future research. PMID:23662111

C3I system modification and EMC (electromagnetic compatibility) methodology, volume 1

NASA Astrophysics Data System (ADS)

Wilson, J. L.; Jolly, M. B.

1984-01-01

A methodology (i.e., consistent set of procedures) for assessing the electromagnetic compatibility (EMC) of RF subsystem modifications on C3I aircraft was generated during this study (Volume 1). An IEMCAP (Intrasystem Electromagnetic Compatibility Analysis Program) database for the E-3A (AWACS) C3I aircraft RF subsystem was extracted to support the design of the EMC assessment methodology (Volume 2). Mock modifications were performed on the E-3A database to assess, using a preliminary form of the methodology, the resulting EMC impact. Application of the preliminary assessment methodology to modifications in the E-3A database served to fine tune the form of a final assessment methodology. The resulting final assessment methodology is documented in this report in conjunction with the overall study goals, procedures, and database. It is recommended that a similar EMC assessment methodology be developed for the power subsystem within C3I aircraft. It is further recommended that future EMC assessment methodologies be developed around expert systems (i.e., computer intelligent agents) to control both the excruciating detail and user requirement for transparency.

Evolution of the methodological quality of controlled clinical trials for myofascial trigger point treatments for the period 1978-2015: A systematic review.

PubMed

Stoop, Rahel; Clijsen, Ron; Leoni, Diego; Soldini, Emiliano; Castellini, Greta; Redaelli, Valentina; Barbero, Marco

2017-08-01

The methodological quality of controlled clinical trials (CCTs) of physiotherapeutic treatment modalities for myofascial trigger points (MTrP) has not been investigated yet. To detect the methodological quality of CCTs for physiotherapy treatments of MTrPs and demonstrating the possible increase over time. Systematic review. A systematic search was conducted in two databases, Physiotherapy Evidence Database (PEDro) and Medicine Medical Literature Analysis and Retrieval System online (MEDLINE), using the same keywords and selection procedure corresponding to pre-defined inclusion criteria. The methodological quality, assessed by the 11-item PEDro scale, served as outcome measure. The CCTs had to compare at least two interventions, where one intervention had to lay within the scope of physiotherapy. Participants had to be diagnosed with myofascial pain syndrome or trigger points (active or latent). A total of n = 230 studies was analysed. The cervico-thoracic region was the most frequently treated body part (n = 143). Electrophysical agent applications was the most frequent intervention. The average methodological quality reached 5.5 on the PEDro scale. A total of n = 6 studies scored the value of 9. The average PEDro score increased by 0.7 points per decade between 1978 and 2015. The average PEDro score of CCTs for MTrP treatments does not reach the cut-off of 6 proposed for moderate to high methodological quality. Nevertheless, a promising trend towards an increase of the average methodological quality of CCTs for MTrPs was recorded. More high-quality CCT studies with thorough research procedures are recommended to enhance methodological quality. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

An Assessment of IMPAC - Integrated Methodology for Propulsion and Airframe Controls

NASA Technical Reports Server (NTRS)

Walker, G. P.; Wagner, E. A.; Bodden, D. S.

1996-01-01

This report documents the work done under a NASA sponsored contract to transition to industry technologies developed under the NASA Lewis Research Center IMPAC (Integrated Methodology for Propulsion and Airframe Control) program. The critical steps in IMPAC are exercised on an example integrated flight/propulsion control design for linear airframe/engine models of a conceptual STOVL (Short Take-Off and Vertical Landing) aircraft, and MATRIXX (TM) executive files to implement each step are developed. The results from the example study are analyzed and lessons learned are listed along with recommendations that will improve the application of each design step. The end product of this research is a set of software requirements for developing a user-friendly control design tool which will automate the steps in the IMPAC methodology. Prototypes for a graphical user interface (GUI) are sketched to specify how the tool will interact with the user, and it is recommended to build the tool around existing computer aided control design software packages.

Delivering successful randomized controlled trials in surgery: Methods to optimize collaboration and study design.

PubMed

Blencowe, Natalie S; Cook, Jonathan A; Pinkney, Thomas; Rogers, Chris; Reeves, Barnaby C; Blazeby, Jane M

2017-04-01

Randomized controlled trials in surgery are notoriously difficult to design and conduct due to numerous methodological and cultural challenges. Over the last 5 years, several UK-based surgical trial-related initiatives have been funded to address these issues. These include the development of Surgical Trials Centers and Surgical Specialty Leads (individual surgeons responsible for championing randomized controlled trials in their specialist fields), both funded by the Royal College of Surgeons of England; networks of research-active surgeons in training; and investment in methodological research relating to surgical randomized controlled trials (to address issues such as recruitment, blinding, and the selection and standardization of interventions). This article discusses these initiatives more in detail and provides exemplar cases to illustrate how the methodological challenges have been tackled. The initiatives have surpassed expectations, resulting in a renaissance in surgical research throughout the United Kingdom, such that the number of patients entering surgical randomized controlled trials has doubled.

Methodological Quality of Randomized Clinical Trials of Respiratory Physiotherapy in Coronary Artery Bypass Grafting Patients in the Intensive Care Unit: a Systematic Review

PubMed Central

Lorscheitter, Jaqueline; Stein, Cinara; Plentz, Rodrigo Della Méa

2017-01-01

Objective To assess methodological quality of the randomized controlled trials of physiotherapy in patients undergoing coronary artery bypass grafting in the intensive care unit. Methods The studies published until May 2015, in MEDLINE, Cochrane and PEDro were included. The primary outcome extracted was proper filling of the Cochrane Collaboration's tool's items and the secondary was suitability to the requirements of the CONSORT Statement and its extension. Results From 807 studies identified, 39 were included. Most at CONSORT items showed a better adequacy after the statement's publication. Studies with positive outcomes presented better methodological quality. Conclusion The methodological quality of the studies has been improving over the years. However, many aspects can still be better designed. PMID:28977205

The relationship between return on investment and quality of study methodology in workplace health promotion programs.

PubMed

Baxter, Siyan; Sanderson, Kristy; Venn, Alison J; Blizzard, C Leigh; Palmer, Andrew J

2014-01-01

To determine the relationship between return on investment (ROI) and quality of study methodology in workplace health promotion programs. Data were obtained through a systematic literature search of National Health Service Economic Evaluation Database (NHS EED), Database of Abstracts of Reviews of Effects (DARE), Health Technology Database (HTA), Cost Effectiveness Analysis (CEA) Registry, EconLit, PubMed, Embase, Wiley, and Scopus. Included were articles written in English or German reporting cost(s) and benefit(s) and single or multicomponent health promotion programs on working adults. Return-to-work and workplace injury prevention studies were excluded. Methodological quality was graded using British Medical Journal Economic Evaluation Working Party checklist. Economic outcomes were presented as ROI. ROI was calculated as ROI = (benefits - costs of program)/costs of program. Results were weighted by study size and combined using meta-analysis techniques. Sensitivity analysis was performed using two additional methodological quality checklists. The influences of quality score and important study characteristics on ROI were explored. Fifty-one studies (61 intervention arms) published between 1984 and 2012 included 261,901 participants and 122,242 controls from nine industry types across 12 countries. Methodological quality scores were highly correlated between checklists (r = .84-.93). Methodological quality improved over time. Overall weighted ROI [mean ± standard deviation (confidence interval)] was 1.38 ± 1.97 (1.38-1.39), which indicated a 138% return on investment. When accounting for methodological quality, an inverse relationship to ROI was found. High-quality studies (n = 18) had a smaller mean ROI, 0.26 ± 1.74 (.23-.30), compared to moderate (n = 16) 0.90 ± 1.25 (.90-.91) and low-quality (n = 27) 2.32 ± 2.14 (2.30-2.33) studies. Randomized control trials (RCTs) (n = 12) exhibited negative ROI, -0.22 ± 2.41(-.27 to -.16). Financial returns become increasingly positive across quasi-experimental, nonexperimental, and modeled studies: 1.12 ± 2.16 (1.11-1.14), 1.61 ± 0.91 (1.56-1.65), and 2.05 ± 0.88 (2.04-2.06), respectively. Overall, mean weighted ROI in workplace health promotion demonstrated a positive ROI. Higher methodological quality studies provided evidence of smaller financial returns. Methodological quality and study design are important determinants.

Comparing U.S. Army suicide cases to a control sample: initial data and methodological lessons.

PubMed

Alexander, Cynthia L; Reger, Mark A; Smolenski, Derek J; Fullerton, Nicole R

2014-10-01

Identification of risk and protective factors for suicide is a priority for the United States military, especially in light of the recent steady increase in military suicide rates. The Department of Defense Suicide Event Report contains comprehensive data on suicides for active duty military personnel, but no analogous control data is available to permit identification of factors that differentially determine suicide risk. This proof-of-concept study was conducted to determine the feasibility of collecting such control data. The study employed a prospective case-control design in which control cases were randomly selected from a large Army installation at a rate of four control participants for every qualifying Army suicide. Although 111 Army suicides were confirmed during the study period, just 27 control soldiers completed the study. Despite the small control sample, preliminary analyses comparing suicide cases to controls identified several factors more frequently reported for suicide cases, including recent failed intimate relationships, outpatient mental health history, mood disorder diagnosis, substance abuse history, and prior self-injury. No deployment-related risk factors were found. These data are consistent with existing literature and form a foundation for larger control studies. Methodological lessons learned regarding study design and recruitment are discussed to inform future studies. Reprint & Copyright © 2014 Association of Military Surgeons of the U.S.

Design of clinical trials of antidepressants: should a placebo control arm be included?

PubMed

Fritze, J; Möller, H J

2001-01-01

There is no doubt that available antidepressants are efficacious and effective. Nevertheless, more effective drugs with improved tolerability are needed. With this need in mind, some protagonists claim that future antidepressants should be proved superior to, or at least as effective as, established antidepressants, making placebo control methodologically dispensable in clinical trials. Moreover, the use of placebo control is criticised as unethical because it might result in effective treatment being withheld. There are, however, a number of methodological reasons why placebo control is indispensable for the proof of efficacy of antidepressants. Comparing investigational antidepressants only with standard antidepressants and not placebo yields ambiguous results that are difficult to interpret, be it in superiority or equivalence testing, and this method of assessment requires larger sample sizes than those required with the use of placebo control. Experimental methodology not adhering to the optimal study design is ethically questionable. Restricting the testing of investigational antidepressants only to superiority over standard antidepressants is an obstacle to therapeutic progress in terms of tolerability and the detection of innovative mechanisms of action from which certain subgroups of future patients might benefit. The use of a methodology that requires larger samples for testing of superiority or equivalence is also ethically questionable. In view of the high placebo response rates in trials of antidepressants, placebo treatment does not mean withholding effective treatment. Accepting the necessity of the clinical evaluation of new, potentially ineffective antidepressants implicitly means accepting placebo control as ethically justified. Three- or multi-arm comparisons including placebo and an active reference represent the optimal study design.

The comparison of various approach to evaluation erosion risks and design control erosion measures

NASA Astrophysics Data System (ADS)

Kapicka, Jiri

2015-04-01

In the present is in the Czech Republic one methodology how to compute and compare erosion risks. This methodology contain also method to design erosion control measures. The base of this methodology is Universal Soil Loss Equation (USLE) and their result long-term average annual rate of erosion (G). This methodology is used for landscape planners. Data and statistics from database of erosion events in the Czech Republic shows that many troubles and damages are from local episodes of erosion events. An extent of these events and theirs impact are conditional to local precipitation events, current plant phase and soil conditions. These erosion events can do troubles and damages on agriculture land, municipally property and hydro components and even in a location is from point of view long-term average annual rate of erosion in good conditions. Other way how to compute and compare erosion risks is episodes approach. In this paper is presented the compare of various approach to compute erosion risks. The comparison was computed to locality from database of erosion events on agricultural land in the Czech Republic where have been records two erosion events. The study area is a simple agriculture land without any barriers that can have high influence to water flow and soil sediment transport. The computation of erosion risks (for all methodology) was based on laboratory analysis of soil samples which was sampled on study area. Results of the methodology USLE, MUSLE and results from mathematical model Erosion 3D have been compared. Variances of the results in space distribution of the places with highest soil erosion where compared and discussed. Other part presents variances of design control erosion measures where their design was done on based different methodology. The results shows variance of computed erosion risks which was done by different methodology. These variances can start discussion about different approach how compute and evaluate erosion risks in areas with different importance.

Reporting and Methodological Quality of Randomised Controlled Trials in Vascular and Endovascular Surgery.

PubMed

Hajibandeh, S; Hajibandeh, S; Antoniou, G A; Green, P A; Maden, M; Torella, F

2015-11-01

Randomised controlled trials (RCTs) are subject to bias if they lack methodological quality. Moreover, optimal and transparent reporting of RCT findings aids their critical appraisal and interpretation. The aim of this study was to ascertain whether the methodological and reporting quality of RCTs in vascular and endovascular surgery is improving. The most recent 75 and oldest 75 RCTs published in leading journals over a 10-year period (2003-2012) were identified. The reporting quality and methodological quality data of the old and new RCTs were extracted and compared. The former was analysed using the Consolidated Standards of Reporting Trials (CONSORT) statement, the latter with the Scottish Intercollegiate Guidelines Network (SIGN) checklist. Reporting quality measured by CONSORT was better in the new studies than in the old studies (0.68 [95% CI, 0.66-0.7] vs. 0.60 [95% CI, 0.58-0.62], p < .001); however, both new and old studies had similar methodological quality measured by SIGN (0.9 [IQR 0.1] vs. .09 [IQR: 0.2], p = .787). Unlike clinical items, the methodological items of the CONSORT statement were not well reported in old and new RCTs. More trials in the new group were endovascular related (33.33% vs. 17.33%, p = .038) and industry sponsored (28% vs. 6.67%, p = .001). Despite some progress, there remains room for improvement in the reporting quality of RCTs in vascular and endovascular surgery. The methodological quality of recent RCTs is similar to that of trials performed >10 years ago. Copyright © 2015 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

The methodological quality assessment tools for preclinical and clinical studies, systematic review and meta-analysis, and clinical practice guideline: a systematic review.

PubMed

Zeng, Xiantao; Zhang, Yonggang; Kwong, Joey S W; Zhang, Chao; Li, Sheng; Sun, Feng; Niu, Yuming; Du, Liang

2015-02-01

To systematically review the methodological assessment tools for pre-clinical and clinical studies, systematic review and meta-analysis, and clinical practice guideline. We searched PubMed, the Cochrane Handbook for Systematic Reviews of Interventions, Joanna Briggs Institute (JBI) Reviewers Manual, Centre for Reviews and Dissemination, Critical Appraisal Skills Programme (CASP), Scottish Intercollegiate Guidelines Network (SIGN), and the National Institute for Clinical Excellence (NICE) up to May 20th, 2014. Two authors selected studies and extracted data; quantitative analysis was performed to summarize the characteristics of included tools. We included a total of 21 assessment tools for analysis. A number of tools were developed by academic organizations, and some were developed by only a small group of researchers. The JBI developed the highest number of methodological assessment tools, with CASP coming second. Tools for assessing the methodological quality of randomized controlled studies were most abundant. The Cochrane Collaboration's tool for assessing risk of bias is the best available tool for assessing RCTs. For cohort and case-control studies, we recommend the use of the Newcastle-Ottawa Scale. The Methodological Index for Non-Randomized Studies (MINORS) is an excellent tool for assessing non-randomized interventional studies, and the Agency for Healthcare Research and Quality (ARHQ) methodology checklist is applicable for cross-sectional studies. For diagnostic accuracy test studies, the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool is recommended; the SYstematic Review Centre for Laboratory animal Experimentation (SYRCLE) risk of bias tool is available for assessing animal studies; Assessment of Multiple Systematic Reviews (AMSTAR) is a measurement tool for systematic reviews/meta-analyses; an 18-item tool has been developed for appraising case series studies, and the Appraisal of Guidelines, Research and Evaluation (AGREE)-II instrument is widely used to evaluate clinical practice guidelines. We have successfully identified a variety of methodological assessment tools for different types of study design. However, further efforts in the development of critical appraisal tools are warranted since there is currently a lack of such tools for other fields, e.g. genetic studies, and some existing tools (nested case-control studies and case reports, for example) are in need of updating to be in line with current research practice and rigor. In addition, it is very important that all critical appraisal tools remain subjective and performance bias is effectively avoided. © 2015 Chinese Cochrane Center, West China Hospital of Sichuan University and Wiley Publishing Asia Pty Ltd.

Methodology for a vaginal and urinary microbiome study in women with mixed urinary incontinence.

PubMed

Komesu, Yuko M; Richter, Holly E; Dinwiddie, Darrell L; Siddiqui, Nazema Y; Sung, Vivian W; Lukacz, Emily S; Ridgeway, Beri; Arya, Lily A; Zyczynski, Halina M; Rogers, Rebecca G; Gantz, Marie

2017-05-01

We describe the rationale and methods of a study designed to compare vaginal and urinary microbiomes in women with mixed urinary incontinence (MUI) and similarly aged, asymptomatic controls. This paper delineates the methodology of a supplementary microbiome study nested in an ongoing randomized controlled trial comparing a standardized perioperative behavioral/pelvic floor exercise intervention plus midurethral sling versus midurethral sling alone for MUI. Women in the parent study had at least "moderate bother" from urgency and stress urinary incontinence symptoms (SUI) on validated questionnaire and confirmed MUI on bladder diary. Controls had no incontinence symptoms. All participants underwent vaginal and urine collection for DNA analysis and conventional urine culture. Standardized protocols were designed, and a central lab received samples for subsequent polymerase chain reaction (PCR) amplification and sequencing of the bacterial16S ribosomal RNA (rRNA) gene. The composition of bacterial communities will be determined by dual amplicon sequencing of variable regions 1-3 and 4-6 from vaginal and urine specimens to compare the microbiome of patients with controls. Sample-size estimates determined that 126 MUI and 84 control participants were sufficient to detect a 20 % difference in predominant urinary genera, with 80 % power and 0.05 significance level. Specimen collection commenced January 2015 and finished April 2016. DNA was extracted and stored for subsequent evaluation. Methods papers sharing information regarding development of genitourinary microbiome studies, particularly with control populations, are few. We describe the rigorous methodology developed for a novel urogenital microbiome study in women with MUI.

Age-Related Deficits in Intentional Memory for Spatial Location in Small-Scale Space: A Meta-Analysis and Methodological Critique.

ERIC Educational Resources Information Center

Foisy, Pierre

1994-01-01

Meta analysis of 22 studies testing 1,598 subjects revealed that aging has a great effect on intentional memory for spatial location. However, methodological limits were found: fewer than half of the studies controlled for age differences in visual acuity or did not use a test phase of fixed duration. (SK)

Integrated design of the CSI evolutionary structure: A verification of the design methodology

NASA Technical Reports Server (NTRS)

Maghami, Peiman G.; Joshi, S. M.; Elliott, Kenny B.; Walz, J. E.

1993-01-01

One of the main objectives of the Controls-Structures Interaction (CSI) program is to develop and evaluate integrated controls-structures design methodology for flexible space structures. Thus far, integrated design methodologies for a class of flexible spacecraft, which require fine attitude pointing and vibration suppression with no payload articulation, have been extensively investigated. Various integrated design optimization approaches, such as single-objective optimization, and multi-objective optimization, have been implemented with an array of different objectives and constraints involving performance and cost measures such as total mass, actuator mass, steady-state pointing performance, transient performance, control power, and many more. These studies have been performed using an integrated design software tool (CSI-DESIGN CODE) which is under development by the CSI-ADM team at the NASA Langley Research Center. To date, all of these studies, irrespective of the type of integrated optimization posed or objectives and constraints used, have indicated that integrated controls-structures design results in an overall spacecraft design which is considerably superior to designs obtained through a conventional sequential approach. Consequently, it is believed that validation of some of these results through fabrication and testing of a structure which is designed through an integrated design approach is warranted. The objective of this paper is to present and discuss the efforts that have been taken thus far for the validation of the integrated design methodology.

PRECEPT: an evidence assessment framework for infectious disease epidemiology, prevention and control.

PubMed

Harder, Thomas; Takla, Anja; Eckmanns, Tim; Ellis, Simon; Forland, Frode; James, Roberta; Meerpohl, Joerg J; Morgan, Antony; Rehfuess, Eva; Schünemann, Holger; Zuiderent-Jerak, Teun; de Carvalho Gomes, Helena; Wichmann, Ole

2017-10-01

Decisions in public health should be based on the best available evidence, reviewed and appraised using a rigorous and transparent methodology. The Project on a Framework for Rating Evidence in Public Health (PRECEPT) defined a methodology for evaluating and grading evidence in infectious disease epidemiology, prevention and control that takes different domains and question types into consideration. The methodology rates evidence in four domains: disease burden, risk factors, diagnostics and intervention. The framework guiding it has four steps going from overarching questions to an evidence statement. In step 1, approaches for identifying relevant key areas and developing specific questions to guide systematic evidence searches are described. In step 2, methodological guidance for conducting systematic reviews is provided; 15 study quality appraisal tools are proposed and an algorithm is given for matching a given study design with a tool. In step 3, a standardised evidence-grading scheme using the Grading of Recommendations Assessment, Development and Evaluation Working Group (GRADE) methodology is provided, whereby findings are documented in evidence profiles. Step 4 consists of preparing a narrative evidence summary. Users of this framework should be able to evaluate and grade scientific evidence from the four domains in a transparent and reproducible way.

PRECEPT: an evidence assessment framework for infectious disease epidemiology, prevention and control

PubMed Central

Harder, Thomas; Takla, Anja; Eckmanns, Tim; Ellis, Simon; Forland, Frode; James, Roberta; Meerpohl, Joerg J; Morgan, Antony; Rehfuess, Eva; Schünemann, Holger; Zuiderent-Jerak, Teun; de Carvalho Gomes, Helena; Wichmann, Ole

2017-01-01

Decisions in public health should be based on the best available evidence, reviewed and appraised using a rigorous and transparent methodology. The Project on a Framework for Rating Evidence in Public Health (PRECEPT) defined a methodology for evaluating and grading evidence in infectious disease epidemiology, prevention and control that takes different domains and question types into consideration. The methodology rates evidence in four domains: disease burden, risk factors, diagnostics and intervention. The framework guiding it has four steps going from overarching questions to an evidence statement. In step 1, approaches for identifying relevant key areas and developing specific questions to guide systematic evidence searches are described. In step 2, methodological guidance for conducting systematic reviews is provided; 15 study quality appraisal tools are proposed and an algorithm is given for matching a given study design with a tool. In step 3, a standardised evidence-grading scheme using the Grading of Recommendations Assessment, Development and Evaluation Working Group (GRADE) methodology is provided, whereby findings are documented in evidence profiles. Step 4 consists of preparing a narrative evidence summary. Users of this framework should be able to evaluate and grade scientific evidence from the four domains in a transparent and reproducible way. PMID:29019317

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

Techniques for designing rotorcraft control systems

NASA Technical Reports Server (NTRS)

Yudilevitch, Gil; Levine, William S.

1994-01-01

Over the last two and a half years we have been demonstrating a new methodology for the design of rotorcraft flight control systems (FCS) to meet handling qualities requirements. This method is based on multicriterion optimization as implemented in the optimization package CONSOL-OPTCAD (C-O). This package has been developed at the Institute for Systems Research (ISR) at the University of Maryland at College Park. This design methodology has been applied to the design of a FCS for the UH-60A helicopter in hover having the ADOCS control structure. The controller parameters have been optimized to meet the ADS-33C specifications. Furthermore, using this approach, an optimal (minimum control energy) controller has been obtained and trade-off studies have been performed.

How effective is the comprehensive approach to rehabilitation (CARe) methodology? A cluster randomized controlled trial.

PubMed

Bitter, Neis; Roeg, Diana; van Assen, Marcel; van Nieuwenhuizen, Chijs; van Weeghel, Jaap

2017-12-11

The CARe methodology aims to improve the quality of life of people with severe mental illness by supporting them in realizing their goals, handling their vulnerability and improving the quality of their social environment. This study aims to investigate the effectiveness of the CARe methodology for people with severe mental illness on their quality of life, personal recovery, participation, hope, empowerment, self-efficacy beliefs and unmet needs. A cluster Randomized Controlled Trial (RCT) was conducted in 14 teams of three organizations for sheltered and supported housing in the Netherlands. Teams in the intervention group received training in the CARe methodology. Teams in the control group continued working according to care as usual. Questionnaires were filled out at baseline, after 10 months and after 20 months. A total of 263 clients participated in the study. Quality of life increased in both groups, however, no differences between the intervention and control group were found. Recovery and social functioning did not change over time. Regarding the secondary outcomes, the number of unmet needs decreased in both groups. All intervention teams received the complete training program. The model fidelity at T1 was 53.4% for the intervention group and 33.4% for the control group. At T2 this was 50.6% for the intervention group and 37.2% for the control group. All clients improved in quality of life. However we did not find significant differences between the clients of the both conditions on any outcome measure. Possible explanations of these results are: the difficulty to implement rehabilitation-supporting practice, the content of the methodology and the difficulty to improve the lives of a group of people with longstanding and severe impairments in a relatively short period. More research is needed on how to improve effects of rehabilitation trainings in practice and on outcome level. ISRCTN77355880 , retrospectively registered (05/07/2013).

Development of weight and cost estimates for lifting surfaces with active controls

NASA Technical Reports Server (NTRS)

Anderson, R. D.; Flora, C. C.; Nelson, R. M.; Raymond, E. T.; Vincent, J. H.

1976-01-01

Equations and methodology were developed for estimating the weight and cost incrementals due to active controls added to the wing and horizontal tail of a subsonic transport airplane. The methods are sufficiently generalized to be suitable for preliminary design. Supporting methodology and input specifications for the weight and cost equations are provided. The weight and cost equations are structured to be flexible in terms of the active control technology (ACT) flight control system specification. In order to present a self-contained package, methodology is also presented for generating ACT flight control system characteristics for the weight and cost equations. Use of the methodology is illustrated.

A dynamic feedback-control toll pricing methodology : a case study on Interstate 95 managed lanes.

DOT National Transportation Integrated Search

2013-06-01

Recently, congestion pricing emerged as a cost-effective and efficient strategy to mitigate the congestion problem on freeways. This study develops a feedback-control based dynamic toll approach to formulate and solve for optimal tolls. The study com...

Nuclear power plant digital system PRA pilot study with the dynamic flow-graph methodology

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

Yau, M.; Motamed, M.; Guarro, S.

2006-07-01

Current Probabilistic Risk Assessment (PRA) methodology is well established in analyzing hardware and some of the key human interactions. However processes for analyzing the software functions of digital systems within a plant PRA framework, and accounting for the digital system contribution to the overall risk are not generally available nor are they well understood and established. A recent study reviewed a number of methodologies that have potential applicability to modeling and analyzing digital systems within a PRA framework. This study identified the Dynamic Flow-graph Methodology (DFM) and the Markov Methodology as the most promising tools. As a result of thismore » study, a task was defined under the framework of a collaborative agreement between the U.S. Nuclear Regulatory Commission (NRC) and the Ohio State Univ. (OSU). The objective of this task is to set up benchmark systems representative of digital systems used in nuclear power plants and to evaluate DFM and the Markov methodology with these benchmark systems. The first benchmark system is a typical Pressurized Water Reactor (PWR) Steam Generator (SG) Feedwater System (FWS) level control system based on an earlier ASCA work with the U.S. NRC 2, upgraded with modern control laws. ASCA, Inc. is currently under contract to OSU to apply DFM to this benchmark system. The goal is to investigate the feasibility of using DFM to analyze and quantify digital system risk, and to integrate the DFM analytical results back into the plant event tree/fault tree PRA model. (authors)« less

Use of qualitative methods alongside randomised controlled trials of complex healthcare interventions: methodological study

PubMed Central

Glenton, Claire; Oxman, Andrew D

2009-01-01

Objective To examine the use of qualitative approaches alongside randomised trials of complex healthcare interventions. Design Review of randomised controlled trials of interventions to change professional practice or the organisation of care. Data sources Systematic sample of 100 trials published in English from the register of the Cochrane Effective Practice and Organisation of Care Review Group. Methods Published and unpublished qualitative studies linked to the randomised controlled trials were identified through database searches and contact with authors. Data were extracted from each study by two reviewers using a standard form. We extracted data describing the randomised controlled trials and qualitative studies, the quality of these studies, and how, if at all, the qualitative and quantitative findings were combined. A narrative synthesis of the findings was done. Results 30 of the 100 trials had associated qualitative work and 19 of these were published studies. 14 qualitative studies were done before the trial, nine during the trial, and four after the trial. 13 studies reported an explicit theoretical basis and 11 specified their methodological approach. Approaches to sampling and data analysis were poorly described. For most cases (n=20) we found no indication of integration of qualitative and quantitative findings at the level of either analysis or interpretation. The quality of the qualitative studies was highly variable. Conclusions Qualitative studies alongside randomised controlled trials remain uncommon, even where relatively complex interventions are being evaluated. Most of the qualitative studies were carried out before or during the trials with few studies used to explain trial results. The findings of the qualitative studies seemed to be poorly integrated with those of the trials and often had major methodological shortcomings. PMID:19744976

Methodological Issues in Design and Analysis of a Matched Case-Control Study of a Vaccine’s Effectiveness

PubMed Central

Niccolai, Linda M.; Ogden, Lorraine G.; Muehlenbein, Catherine E.; Dziura, James D.; Vázquez, Marietta; Shapiro, Eugene D.

2007-01-01

Objective Case-control studies of the effectiveness of a vaccine are useful to answer important questions, such as the effectiveness of a vaccine over time, that usually are not addressed by pre-licensure clinical trials of the vaccine’s efficacy. This report describes methodological issues related to design and analysis that were used to determine the effects of time since vaccination and age at the time of vaccination. Study Design and Setting A matched case-control study of the effectiveness of varicella vaccine. Results Sampling procedures and conditional logistic regression models including interaction terms are described. Conclusion Use of these methods will allow investigators to assess the effects of a wide range of variables, such as time since vaccination and age at the time of vaccination, on the effectiveness of a vaccine. PMID:17938054

Characterizing Postural Sway during Quiet Stance Based on the Intermittent Control Hypothesis

NASA Astrophysics Data System (ADS)

Nomura, Taishin; Nakamura, Toru; Fukada, Kei; Sakoda, Saburo

2007-07-01

This article illustrates a signal processing methodology for the time series of postural sway and accompanied electromyographs from the lower limb muscles during quiet stance. It was shown that the proposed methodology was capable of identifying the underlying postural control mechanisms. A preliminary application of the methodology provided evidence that supports the intermittent control hypothesis alternative to the conventional stiffness control hypothesis during human quiet upright stance.

Economic Effects of Increased Control Zone Sizes in Conflict Resolution

NASA Technical Reports Server (NTRS)

Datta, Koushik

1998-01-01

A methodology for estimating the economic effects of different control zone sizes used in conflict resolutions between aircraft is presented in this paper. The methodology is based on estimating the difference in flight times of aircraft with and without the control zone, and converting the difference into a direct operating cost. Using this methodology the effects of increased lateral and vertical control zone sizes are evaluated.

Efficacy and safety of Suanzaoren decoction for primary insomnia: a systematic review of randomized controlled trials

PubMed Central

2013-01-01

Background Insomnia is a widespread human health problem, but there currently are the limitations of conventional therapies available. Suanzaoren decoction (SZRD) is a well known classic Chinese herbal prescription for insomnia and has been treating people’s insomnia for more than thousand years. The objective of this study was to evaluate the efficacy and safety of SZRD for insomnia. Methods A systematic literature search was performed for 6 databases up to July of 2012 to identify randomized control trials (RCTs) involving SZRD for insomniac patients. The methodological quality of RCTs was assessed independently using the Cochrane Handbook for Systematic Reviews of Interventions. Results Twelve RCTs with total of 1376 adult participants were identified. The methodological quality of all included trials are no more than 3/8 score. Majority of the RCTs concluded that SZRD was more significantly effective than benzodiazepines for treating insomnia. Despite these positive outcomes, there were many methodological shortcomings in the studies reviewed, including insufficient information about randomization generation and absence of allocation concealment, lack of blinding and no placebo control, absence of intention-to-treat analysis and lack of follow-ups, selective publishing and reporting, and small number of sample sizes. A number of clinical heterogeneity such as diagnosis, intervention, control, and outcome measures were also reviewed. Only 3 trials reported adverse events, whereas the other 9 trials did not provide the safety information. Conclusions Despite the apparent reported positive findings, there is insufficient evidence to support efficacy of SZRD for insomnia due to the poor methodological quality and the small number of trials of the included studies. SZRD seems generally safe, but is insufficient evidence to make conclusions on the safety because fewer studies reported the adverse events. Further large sample-size and well-designed RCTs are needed. PMID:23336848

Effectiveness of voice therapy in functional dysphonia: where are we now?

PubMed

Bos-Clark, Marianne; Carding, Paul

2011-06-01

To review the recent literature since the 2009 Cochrane review regarding the effectiveness of voice therapy for patients with functional dysphonia. A range of articles report on the effects of voice therapy treatment for functional dysphonia, with a wide range of interventions described. Only one study is a randomized controlled trial. A number of excellent review articles have extended the knowledge base. In primary research, methodological issues persist: studies are small, and not adequately controlled. Studies show improved standards of outcome measurement and of description of the content of voice therapy. There is a continued need for larger, methodologically sound clinical effectiveness studies. Future studies need to be replicable and generalizable in order to inform and elucidate clinical practice.

Extended cooperative control synthesis

NASA Technical Reports Server (NTRS)

Davidson, John B.; Schmidt, David K.

1994-01-01

This paper reports on research for extending the Cooperative Control Synthesis methodology to include a more accurate modeling of the pilot's controller dynamics. Cooperative Control Synthesis (CCS) is a methodology that addresses the problem of how to design control laws for piloted, high-order, multivariate systems and/or non-conventional dynamic configurations in the absence of flying qualities specifications. This is accomplished by emphasizing the parallel structure inherent in any pilot-controlled, augmented vehicle. The original CCS methodology is extended to include the Modified Optimal Control Model (MOCM), which is based upon the optimal control model of the human operator developed by Kleinman, Baron, and Levison in 1970. This model provides a modeling of the pilot's compensation dynamics that is more accurate than the simplified pilot dynamic representation currently in the CCS methodology. Inclusion of the MOCM into the CCS also enables the modeling of pilot-observation perception thresholds and pilot-observation attention allocation affects. This Extended Cooperative Control Synthesis (ECCS) allows for the direct calculation of pilot and system open- and closed-loop transfer functions in pole/zero form and is readily implemented in current software capable of analysis and design for dynamic systems. Example results based upon synthesizing an augmentation control law for an acceleration command system in a compensatory tracking task using the ECCS are compared with a similar synthesis performed by using the original CCS methodology. The ECCS is shown to provide augmentation control laws that yield more favorable, predicted closed-loop flying qualities and tracking performance than those synthesized using the original CCS methodology.

Control design for future agile fighters

NASA Technical Reports Server (NTRS)

Murphy, Patrick C.; Davidson, John B.

1991-01-01

The CRAFT control design methodology is presented. CRAFT stands for the design objectives addressed, namely, Control power, Robustness, Agility, and Flying Qualities Tradeoffs. The approach combines eigenspace assignment, which allows for direct specification of eigenvalues and eigenvectors, and a graphical approach for representing control design metrics that captures numerous design goals in one composite illustration. The methodology makes use of control design metrics from four design objective areas, namely, control power, robustness, agility, and flying qualities. An example of the CRAFT methodology as well as associated design issues are presented.

The Methodology of Clinical Studies Used by the FDA for Approval of High-Risk Orthopaedic Devices.

PubMed

Barker, Jordan P; Simon, Stephen D; Dubin, Jonathan

2017-05-03

The purpose of this investigation was to examine the methodology of clinical trials used by the U.S. Food and Drug Administration (FDA) to determine the safety and effectiveness of high-risk orthopaedic devices approved between 2001 and 2015. Utilizing the FDA's online public database, this systematic review audited study design and methodological variables intended to minimize bias and confounding. An additional analysis of blinding as well as the Checklist to Evaluate a Report of a Nonpharmacological Trial (CLEAR NPT) was applied to the randomized controlled trials (RCTs). Of the 49 studies, 46 (94%) were prospective and 37 (76%) were randomized. Forty-seven (96%) of the studies were controlled in some form. Of 35 studies that reported it, blinding was utilized in 21 (60%), of which 8 (38%) were reported as single-blinded and 13 (62%) were reported as double-blinded. Of the 37 RCTs, outcome assessors were clearly blinded in 6 (16%), whereas 15 (41%) were deemed impossible to blind as implants could be readily discerned on imaging. When the CLEAR NPT was applied to the 37 RCTs, >70% of studies were deemed "unclear" in describing generation of allocation sequences, treatment allocation concealment, and adequate blinding of participants and outcome assessors. This study manifests the highly variable reporting and strength of clinical research methodology accepted by the FDA to approve high-risk orthopaedic devices.

Development and testing of methodology for evaluating the performance of multi-input/multi-output digital control systems

NASA Technical Reports Server (NTRS)

Polotzky, Anthony S.; Wieseman, Carol; Hoadley, Sherwood Tiffany; Mukhopadhyay, Vivek

1990-01-01

The development of a controller performance evaluation (CPE) methodology for multiinput/multioutput digital control systems is described. The equations used to obtain the open-loop plant, controller transfer matrices, and return-difference matrices are given. Results of applying the CPE methodology to evaluate MIMO digital flutter suppression systems being tested on an active flexible wing wind-tunnel model are presented to demonstrate the CPE capability.

Experimental Validation of an Integrated Controls-Structures Design Methodology

NASA Technical Reports Server (NTRS)

Maghami, Peiman G.; Gupta, Sandeep; Elliot, Kenny B.; Walz, Joseph E.

1996-01-01

The first experimental validation of an integrated controls-structures design methodology for a class of large order, flexible space structures is described. Integrated redesign of the controls-structures-interaction evolutionary model, a laboratory testbed at NASA Langley, was described earlier. The redesigned structure was fabricated, assembled in the laboratory, and experimentally tested against the original structure. Experimental results indicate that the structure redesigned using the integrated design methodology requires significantly less average control power than the nominal structure with control-optimized designs, while maintaining the required line-of-sight pointing performance. Thus, the superiority of the integrated design methodology over the conventional design approach is experimentally demonstrated. Furthermore, amenability of the integrated design structure to other control strategies is evaluated, both analytically and experimentally. Using Linear-Quadratic-Guassian optimal dissipative controllers, it is observed that the redesigned structure leads to significantly improved performance with alternate controllers as well.

Hormonal Control of Fetal Growth.

ERIC Educational Resources Information Center

Cooke, Paul S.; Nicoll, Charles S.

1983-01-01

Summarizes recent research on hormonal control of fetal growth, presenting data obtained using a new method for studying the area. Effects of endocrine ablations and congenital deficiencies, studies of hormone/receptor levels, in-vitro techniques, hormones implicated in promoting fetal growth, problems with existing methodologies, and growth of…

[Methodological quality of articles on therapeutic procedures published in Cirugía Española. Evaluation of the period 2005-2008].

PubMed

Manterola, Carlos; Grande, Luís

2010-04-01

To determine methodological quality of therapy articles published in Cirugía Española and to study its association with the publication year, the centre of origin and subjects. A literature study which included all therapy articles published between 2005 and 2008. All kinds of clinical designs were considered, excluding editorials, review articles, letters to editor and experimental studies. Variables analysed included: year of publication, centre of origin, design, and methodological quality of articles. A valid and reliable scale was applied to determine methodological quality. A total of 243 articles [206 series of cases (84.8%), 27 cohort studies (11.1%), 9 clinical trials (3.7%) and 1 case control study (0.4%)] were found. Studies came preferentially from Catalonia and Valencia (22.3% and 12.3% respectively). Thematic areas most frequently found were hepato-bilio-pancreatic and colorectal surgery (20.0% and 16.6%, respectively). Average and median of the methodological quality score calculated for the entire series were 9.5+/-4.3 points and 8 points, respectively. Association between methodological quality and geographical area (p=0.0101), subject area (p=0.0267), and university origin (p=0.0369) was found. A significant increase of methodological quality by publication year was observed (p=0.0004). Methodological quality of therapy articles published in Cirugía Española between 2005 and 2008 is low; but an increase tendency with statistical significance was observed.

Design for performance enhancement in feedback control systems with multiple saturating nonlinearities. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Kapasouris, Petros

1988-01-01

A systematic control design methodology is introduced for multi-input/multi-output systems with multiple saturations. The methodology can be applied to stable and unstable open loop plants with magnitude and/or rate control saturations and to systems in which state limitations are desired. This new methodology is a substantial improvement over previous heuristic single-input/single-output approaches. The idea is to introduce a supervisor loop so that when the references and/or disturbances are sufficiently small, the control system operates linearly as designed. For signals large enough to cause saturations, the control law is modified in such a way to ensure stability and to preserve, to the extent possible, the behavior of the linear control design. Key benefits of this methodology are: the modified compensator never produces saturating control signals, integrators and/or slow dynamics in the compensator never windup, the directional properties of the controls are maintained, and the closed loop system has certain guaranteed stability properties. The advantages of the new design methodology are illustrated by numerous simulations, including the multivariable longitudinal control of modified models of the F-8 (stable) and F-16 (unstable) aircraft.

Integrating automated support for a software management cycle into the TAME system

NASA Technical Reports Server (NTRS)

Sunazuka, Toshihiko; Basili, Victor R.

1989-01-01

Software managers are interested in the quantitative management of software quality, cost and progress. An integrated software management methodology, which can be applied throughout the software life cycle for any number purposes, is required. The TAME (Tailoring A Measurement Environment) methodology is based on the improvement paradigm and the goal/question/metric (GQM) paradigm. This methodology helps generate a software engineering process and measurement environment based on the project characteristics. The SQMAR (software quality measurement and assurance technology) is a software quality metric system and methodology applied to the development processes. It is based on the feed forward control principle. Quality target setting is carried out before the plan-do-check-action activities are performed. These methodologies are integrated to realize goal oriented measurement, process control and visual management. A metric setting procedure based on the GQM paradigm, a management system called the software management cycle (SMC), and its application to a case study based on NASA/SEL data are discussed. The expected effects of SMC are quality improvement, managerial cost reduction, accumulation and reuse of experience, and a highly visual management reporting system.

Methodologies for Root Locus and Loop Shaping Control Design with Comparisons

NASA Technical Reports Server (NTRS)

Kopasakis, George

2017-01-01

This paper describes some basics for the root locus controls design method as well as for loop shaping, and establishes approaches to expedite the application of these two design methodologies to easily obtain control designs that meet requirements with superior performance. The two design approaches are compared for their ability to meet control design specifications and for ease of application using control design examples. These approaches are also compared with traditional Proportional Integral Derivative (PID) control in order to demonstrate the limitations of PID control. Robustness of these designs is covered as it pertains to these control methodologies and for the example problems.

Integrated Controls-Structures Design Methodology: Redesign of an Evolutionary Test Structure

NASA Technical Reports Server (NTRS)

Maghami, Peiman G.; Gupta, Sandeep; Elliot, Kenny B.; Joshi, Suresh M.

1997-01-01

An optimization-based integrated controls-structures design methodology for a class of flexible space structures is described, and the phase-0 Controls-Structures-Integration evolutionary model, a laboratory testbed at NASA Langley, is redesigned using this integrated design methodology. The integrated controls-structures design is posed as a nonlinear programming problem to minimize the control effort required to maintain a specified line-of-sight pointing performance, under persistent white noise disturbance. Static and dynamic dissipative control strategies are employed for feedback control, and parameters of these controllers are considered as the control design variables. Sizes of strut elements in various sections of the CEM are used as the structural design variables. Design guides for the struts are developed and employed in the integrated design process, to ensure that the redesigned structure can be effectively fabricated. The superiority of the integrated design methodology over the conventional design approach is demonstrated analytically by observing a significant reduction in the average control power needed to maintain specified pointing performance with the integrated design approach.

The Perceptions of U.S.-Based IT Security Professionals about the Effectiveness of IT Security Frameworks: A Quantitative Study

ERIC Educational Resources Information Center

Warfield, Douglas L.

2011-01-01

The evolution of information technology has included new methodologies that use information technology to control and manage various industries and government activities. Information Technology has also evolved as its own industry with global networks of interconnectivity, such as the Internet, and frameworks, models, and methodologies to control…

One Controller at a Time (1-CAT): A mimo design methodology

NASA Technical Reports Server (NTRS)

Mitchell, J. R.; Lucas, J. C.

1987-01-01

The One Controller at a Time (1-CAT) methodology for designing digital controllers for Large Space Structures (LSS's) is introduced and illustrated. The flexible mode problem is first discussed. Next, desirable features of a LSS control system design methodology are delineated. The 1-CAT approach is presented, along with an analytical technique for carrying out the 1-CAT process. Next, 1-CAT is used to design digital controllers for the proposed Space Based Laser (SBL). Finally, the SBL design is evaluated for dynamical performance, noise rejection, and robustness.

Towards the Engineering of Dependable P2P-Based Network Control — The Case of Timely Routing Control Messages

NASA Astrophysics Data System (ADS)

Tutschku, Kurt; Nakao, Akihiro

This paper introduces a methodology for engineering best-effort P2P algorithms into dependable P2P-based network control mechanism. The proposed method is built upon an iterative approach consisting of improving the original P2P algorithm by appropriate mechanisms and of thorough performance assessment with respect to dependability measures. The potential of the methodology is outlined by the example of timely routing control for vertical handover in B3G wireless networks. In detail, the well-known Pastry and CAN algorithms are enhanced to include locality. By showing how to combine algorithmic enhancements with performance indicators, this case study paves the way for future engineering of dependable network control mechanisms through P2P algorithms.

A Proposal for Six Sigma Integration for Large-Scale Production of Penicillin G and Subsequent Conversion to 6-APA.

PubMed

Nandi, Anirban; Pan, Sharadwata; Potumarthi, Ravichandra; Danquah, Michael K; Sarethy, Indira P

2014-01-01

Six Sigma methodology has been successfully applied to daily operations by several leading global private firms including GE and Motorola, to leverage their net profits. Comparatively, limited studies have been conducted to find out whether this highly successful methodology can be applied to research and development (R&D). In the current study, we have reviewed and proposed a process for a probable integration of Six Sigma methodology to large-scale production of Penicillin G and its subsequent conversion to 6-aminopenicillanic acid (6-APA). It is anticipated that the important aspects of quality control and quality assurance will highly benefit from the integration of Six Sigma methodology in mass production of Penicillin G and/or its conversion to 6-APA.

A Proposal for Six Sigma Integration for Large-Scale Production of Penicillin G and Subsequent Conversion to 6-APA

PubMed Central

Nandi, Anirban; Danquah, Michael K.

2014-01-01

Six Sigma methodology has been successfully applied to daily operations by several leading global private firms including GE and Motorola, to leverage their net profits. Comparatively, limited studies have been conducted to find out whether this highly successful methodology can be applied to research and development (R&D). In the current study, we have reviewed and proposed a process for a probable integration of Six Sigma methodology to large-scale production of Penicillin G and its subsequent conversion to 6-aminopenicillanic acid (6-APA). It is anticipated that the important aspects of quality control and quality assurance will highly benefit from the integration of Six Sigma methodology in mass production of Penicillin G and/or its conversion to 6-APA. PMID:25057428

Neuroimaging of Human Balance Control: A Systematic Review

PubMed Central

Wittenberg, Ellen; Thompson, Jessica; Nam, Chang S.; Franz, Jason R.

2017-01-01

This review examined 83 articles using neuroimaging modalities to investigate the neural correlates underlying static and dynamic human balance control, with aims to support future mobile neuroimaging research in the balance control domain. Furthermore, this review analyzed the mobility of the neuroimaging hardware and research paradigms as well as the analytical methodology to identify and remove movement artifact in the acquired brain signal. We found that the majority of static balance control tasks utilized mechanical perturbations to invoke feet-in-place responses (27 out of 38 studies), while cognitive dual-task conditions were commonly used to challenge balance in dynamic balance control tasks (20 out of 32 studies). While frequency analysis and event related potential characteristics supported enhanced brain activation during static balance control, that in dynamic balance control studies was supported by spatial and frequency analysis. Twenty-three of the 50 studies utilizing EEG utilized independent component analysis to remove movement artifacts from the acquired brain signals. Lastly, only eight studies used truly mobile neuroimaging hardware systems. This review provides evidence to support an increase in brain activation in balance control tasks, regardless of mechanical, cognitive, or sensory challenges. Furthermore, the current body of literature demonstrates the use of advanced signal processing methodologies to analyze brain activity during movement. However, the static nature of neuroimaging hardware and conventional balance control paradigms prevent full mobility and limit our knowledge of neural mechanisms underlying balance control. PMID:28443007

Implementation and evaluation of a pharmacist-led hypertension management service in primary care: outcomes and methodological challenges.

PubMed

Bajorek, Beata; Lemay, Kate S; Magin, Parker; Roberts, Christopher; Krass, Ines; Armour, Carol L

2016-01-01

Suboptimal utilisation of pharmacotherapy, non-adherence to prescribed treatment, and a lack of monitoring all contribute to poor blood (BP) pressure control in patients with hypertension. The objective of this study was to evaluate the implementation of a pharmacist-led hypertension management service in terms of processes, outcomes, and methodological challenges. A prospective, controlled study was undertaken within the Australian primary care setting. Community pharmacists were recruited to one of three study groups: Group A (Control - usual care), Group B (Intervention), or Group C (Short Intervention). Pharmacists in Groups B and C delivered a service comprising screening and monitoring of BP, as well as addressing poor BP control through therapeutic adjustment and adherence strategies. Pharmacists in Group C delivered the shortened version of the service. Significant changes to key outcome measures were observed in Group C: reduction in systolic and diastolic BPs at the 3-month visit (P<0.01 and P<0.01, respectively), improvement in medication adherence scores (P=0.01), and a slight improvement in quality of life (EQ-5D-3L Index) scores (P=0.91). There were no significant changes in Group B (the full intervention), and no differences in comparison to Group A (usual care). Pharmacists fed-back that patient recruitment was a key barrier to service implementation, highlighting the methodological implications of screening. A collaborative, pharmacist-led hypertension management service can help monitor BP, improve medication adherence, and optimise therapy in a step-wise approach. However, blood pressure screening can effect behaviour change in patients, presenting methodological challenges in the evaluation of services in this context.

Implementation and evaluation of a pharmacist-led hypertension management service in primary care: outcomes and methodological challenges

PubMed Central

2016-01-01

Background: Suboptimal utilisation of pharmacotherapy, non-adherence to prescribed treatment, and a lack of monitoring all contribute to poor blood (BP) pressure control in patients with hypertension. Objective: The objective of this study was to evaluate the implementation of a pharmacist-led hypertension management service in terms of processes, outcomes, and methodological challenges. Method: A prospective, controlled study was undertaken within the Australian primary care setting. Community pharmacists were recruited to one of three study groups: Group A (Control – usual care), Group B (Intervention), or Group C (Short Intervention). Pharmacists in Groups B and C delivered a service comprising screening and monitoring of BP, as well as addressing poor BP control through therapeutic adjustment and adherence strategies. Pharmacists in Group C delivered the shortened version of the service. Results: Significant changes to key outcome measures were observed in Group C: reduction in systolic and diastolic BPs at the 3-month visit (P<0.01 and P<0.01, respectively), improvement in medication adherence scores (P=0.01), and a slight improvement in quality of life (EQ-5D-3L Index) scores (P=0.91). There were no significant changes in Group B (the full intervention), and no differences in comparison to Group A (usual care). Pharmacists fed-back that patient recruitment was a key barrier to service implementation, highlighting the methodological implications of screening. Conclusion: A collaborative, pharmacist-led hypertension management service can help monitor BP, improve medication adherence, and optimise therapy in a step-wise approach. However, blood pressure screening can effect behaviour change in patients, presenting methodological challenges in the evaluation of services in this context. PMID:27382427

Sampling-Based Stochastic Sensitivity Analysis Using Score Functions for RBDO Problems with Correlated Random Variables

DTIC Science & Technology

2010-08-01

a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. a ...SECURITY CLASSIFICATION OF: This study presents a methodology for computing stochastic sensitivities with respect to the design variables, which are the...Random Variables Report Title ABSTRACT This study presents a methodology for computing stochastic sensitivities with respect to the design variables

Attack Methodology Analysis: Emerging Trends in Computer-Based Attack Methodologies and Their Applicability to Control System Networks

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

Bri Rolston

2005-06-01

Threat characterization is a key component in evaluating the threat faced by control systems. Without a thorough understanding of the threat faced by critical infrastructure networks, adequate resources cannot be allocated or directed effectively to the defense of these systems. Traditional methods of threat analysis focus on identifying the capabilities and motivations of a specific attacker, assessing the value the adversary would place on targeted systems, and deploying defenses according to the threat posed by the potential adversary. Too many effective exploits and tools exist and are easily accessible to anyone with access to an Internet connection, minimal technical skills,more » and a significantly reduced motivational threshold to be able to narrow the field of potential adversaries effectively. Understanding how hackers evaluate new IT security research and incorporate significant new ideas into their own tools provides a means of anticipating how IT systems are most likely to be attacked in the future. This research, Attack Methodology Analysis (AMA), could supply pertinent information on how to detect and stop new types of attacks. Since the exploit methodologies and attack vectors developed in the general Information Technology (IT) arena can be converted for use against control system environments, assessing areas in which cutting edge exploit development and remediation techniques are occurring can provide significance intelligence for control system network exploitation, defense, and a means of assessing threat without identifying specific capabilities of individual opponents. Attack Methodology Analysis begins with the study of what exploit technology and attack methodologies are being developed in the Information Technology (IT) security research community within the black and white hat community. Once a solid understanding of the cutting edge security research is established, emerging trends in attack methodology can be identified and the gap between those threats and the defensive capabilities of control systems can be analyzed. The results of the gap analysis drive changes in the cyber security of critical infrastructure networks to close the gap between current exploits and existing defenses. The analysis also provides defenders with an idea of how threat technology is evolving and how defenses will need to be modified to address these emerging trends.« less

[What is the methodological quality of articles on therapeutic procedures published in Cirugía Española?].

PubMed

Manterola, Carlos; Busquets, Juli; Pascual, Marta; Grande, Luis

2006-02-01

The aim of this study was to determine the methodological quality of articles on therapeutic procedures published in Cirugía Española and to study its association with the publication year, center, and subject-matter. A bibliometric study that included all articles on therapeutic procedures published in Cirugía Española between 2001 and 2004 was performed. All kinds of clinical designs were considered, excluding editorials, review articles, letters to editor, and experimental studies. The variables analyzed were: year of publication, center, design, and methodological quality. Methodological quality was determined by a valid and reliable scale. Descriptive statistics (calculation of means, standard deviation and medians) and analytical statistics (Pearson's chi2, nonparametric, ANOVA and Bonferroni tests) were used. A total of 244 articles were studied (197 case series [81%], 28 cohort studies [12%], 17 clinical trials [7%], 1 cross sectional study and 1 case-control study [0.8%]). The studies were performed mainly in Catalonia and Murcia (22% and 16%, respectively). The most frequent subject areas were soft tissue and hepatobiliopancreatic surgery (23% and 19%, respectively). The mean and median of the methodological quality score calculated for the entire series was 10.2 +/- 3.9 points and 9.5 points, respectively. Methodological quality significantly increased by publication year (p < 0.001). An association between methodological quality and subject area was observed but no association was detected with the center performing the study. The methodological quality of articles on therapeutic procedures published in Cirugía Española between 2001 and 2004 is low. However, a statistically significant trend toward improvement was observed.

Improving guideline adherence through intensive quality improvement and the use of a National Quality Register in Sweden for acute myocardial infarction.

PubMed

Peterson, Anette; Carlhed, Rickard; Lindahl, Bertil; Lindström, Gunilla; Aberg, Christina; Andersson-Gäre, Boel; Bojestig, Mats

2007-01-01

Data from the Swedish National Register in Cardiac Care have shown over the last 10 years an enduring gap between optimal treatment of acute myocardial infarction (AMI) according to current guidelines and the treatment actually given. We performed a controlled, prospective study in order to evaluate the effects of applying a multidisciplinary team-based improvement methodology to the use of evidence-based treatments in AMI, together with the use of a modified National Quality Register. The project engaged 25% of the Swedish hospitals. Multidisciplinary teams from 20 hospitals participating in the National Register in Cardiac Care, ranging from small to large hospitals, were trained in continuous quality improvement methodology. Twenty matched hospitals served as controls. Our efforts were focused on finding and applying tools and methods to increase adherence to the national guidelines for 5 different treatments for AMI. For measurement, specially designed quality control charts were made available in the National Register for Cardiac Care. To close the gap, an important issue for the teams was to get all 5 treatments in place. Ten of the hospitals in the study group reduced the gap in 5 of 5 treatments by 50%, while none of the control hospitals did so. This first, controlled prospective study of a registry supported by multidisciplinary team-based improvement methodology showed that this approach led to rapidly improved adherence to AMI guidelines in a broad spectrum of hospitals and that National Quality Registers can be helpful tools.

Advanced piloted aircraft flight control system design methodology. Volume 1: Knowledge base

NASA Technical Reports Server (NTRS)

Mcruer, Duane T.; Myers, Thomas T.

1988-01-01

The development of a comprehensive and electric methodology for conceptual and preliminary design of flight control systems is presented and illustrated. The methodology is focused on the design stages starting with the layout of system requirements and ending when some viable competing system architectures (feedback control structures) are defined. The approach is centered on the human pilot and the aircraft as both the sources of, and the keys to the solution of, many flight control problems. The methodology relies heavily on computational procedures which are highly interactive with the design engineer. To maximize effectiveness, these techniques, as selected and modified to be used together in the methodology, form a cadre of computational tools specifically tailored for integrated flight control system preliminary design purposes. While theory and associated computational means are an important aspect of the design methodology, the lore, knowledge and experience elements, which guide and govern applications are critical features. This material is presented as summary tables, outlines, recipes, empirical data, lists, etc., which encapsulate a great deal of expert knowledge. Much of this is presented in topical knowledge summaries which are attached as Supplements. The composite of the supplements and the main body elements constitutes a first cut at a a Mark 1 Knowledge Base for manned-aircraft flight control.

Evaluating psychiatric case-control studies using the STROBE (STrengthening the Reporting of OBservational Studies in Epidemiology) statement.

PubMed

Goi, Pedro Domingues; Goi, Julia Domingues; Cordini, Kariny Larissa; Ceresér, Keila Mendes; Rocha, Neusa Sica da

2014-01-01

Case-control studies are important in developing clinical and public health knowledge. The STROBE statement (STrengthening the Reporting of OBservational Studies in Epidemiology) was developed to establish a checklist of items that should be included in articles reporting observational studies. Our aim was to analyze whether the psychiatric case-control articles published in Brazilian journals with CAPES Qualis rating B1/B2 in 2009 conformed with the STROBE statement. Descriptive study on psychiatric papers published in Brazilian journals, within the Postgraduate Medical Program on Psychiatry, at Universidade Federal do Rio Grande do Sul. All psychiatric case-control studies from Brazilian Qualis B1/B2 journals of psychiatry, neurology and public health in 2009 were analyzed. The four most specific items of the STROBE statement were used to evaluate whether these studies fitted within the case-control parameters: 1) selection of cases and controls; 2) controlling for bias; 3) statistical analysis; and 4) presentation of results. Sixteen case-control studies were identified, of which eleven (68.75%) were in psychiatry-focused journals. From analysis using the STROBE statement, all of the articles conformed with item 1; two (12.5%) completely conformed with item 2; none completely conformed with item 3; and only three (18.8%) conformed with item 4. The case-control studies analyzed here did not completely conform with the four STROBE statement items for case-control design. In view of the inadequate methodology of the published studies, these findings justify focusing on research and methodology and expanding the investigations on adherence of studies to their designs.

Generalized Predictive and Neural Generalized Predictive Control of Aerospace Systems

NASA Technical Reports Server (NTRS)

Kelkar, Atul G.

2000-01-01

The research work presented in this thesis addresses the problem of robust control of uncertain linear and nonlinear systems using Neural network-based Generalized Predictive Control (NGPC) methodology. A brief overview of predictive control and its comparison with Linear Quadratic (LQ) control is given to emphasize advantages and drawbacks of predictive control methods. It is shown that the Generalized Predictive Control (GPC) methodology overcomes the drawbacks associated with traditional LQ control as well as conventional predictive control methods. It is shown that in spite of the model-based nature of GPC it has good robustness properties being special case of receding horizon control. The conditions for choosing tuning parameters for GPC to ensure closed-loop stability are derived. A neural network-based GPC architecture is proposed for the control of linear and nonlinear uncertain systems. A methodology to account for parametric uncertainty in the system is proposed using on-line training capability of multi-layer neural network. Several simulation examples and results from real-time experiments are given to demonstrate the effectiveness of the proposed methodology.

Sensory re-education after nerve injury of the upper limb: a systematic review.

PubMed

Oud, Tanja; Beelen, Anita; Eijffinger, Elianne; Nollet, Frans

2007-06-01

To systematically review the available evidence for the effectiveness of sensory re-education to improve the sensibility of the hand in patients with a peripheral nerve injury of the upper limb. Studies were identified by an electronic search in the databases MEDLINE, Cumulative Index to Nursing & Allied Health Literature (CINAHL), EMBASE, the Cochrane Library, the Physiotherapy Evidence Database (PEDro), and the database of the Dutch National Institute of Allied Health Professions (Doconline) and by screening the reference lists of relevant articles. Two reviewers selected studies that met the following inclusion criteria: all designs except case reports, adults with impaired sensibility of the hand due to a peripheral nerve injury of the upper limb, and sensibility and functional sensibility as outcome measures. The methodological quality of the included studies was independently assessed by two reviewers. A best-evidence synthesis was performed, based on design, methodological quality and significant findings on outcome measures. Seven studies, with sample sizes ranging from 11 to 49, were included in the systematic review and appraised for content. Five of these studies were of poor methodological quality. One uncontrolled study (N = 1 3 ) was considered to be of sufficient methodological quality, and one randomized controlled trial (N = 49) was of high methodological quality. Best-evidence synthesis showed that there is limited evidence for the effectiveness of sensory re-education, provided by a statistically significant improvement in sensibility found in one high-quality randomized controlled trial. There is a need for further well-defined clinical trials to assess the effectiveness of sensory re-education of patients with impaired sensibility of the hand due to a peripheral nerve injury.

Design of feedback control systems for stable plants with saturating actuators

NASA Technical Reports Server (NTRS)

Kapasouris, Petros; Athans, Michael; Stein, Gunter

1988-01-01

A systematic control design methodology is introduced for multi-input/multi-output stable open loop plants with multiple saturations. This new methodology is a substantial improvement over previous heuristic single-input/single-output approaches. The idea is to introduce a supervisor loop so that when the references and/or disturbances are sufficiently small, the control system operates linearly as designed. For signals large enough to cause saturations, the control law is modified in such a way as to ensure stability and to preserve, to the extent possible, the behavior of the linear control design. Key benefits of the methodology are: the modified compensator never produces saturating control signals, integrators and/or slow dynamics in the compensator never windup, the directional properties of the controls are maintained, and the closed loop system has certain guaranteed stability properties. The advantages of the new design methodology are illustrated in the simulation of an academic example and the simulation of the multivariable longitudinal control of a modified model of the F-8 aircraft.

Financial conflicts of interest and their association with outcome and quality of fibromyalgia drug therapy randomized controlled trials.

PubMed

Pang, Winnie K; Yeter, Karen C; Torralba, Karina D; Spencer, Horace J; Khan, Nasim A

2015-07-01

To evaluate the association of financial conflicts of interest (FCOI) with the characteristics, outcome and reported methodological quality of fibromyalgia drug therapy randomized controlled trials (FM-RCTs). A cross-sectional study of original, parallel-group, drug therapy FM-RCTs published between 1997 and 2011 from Medline and Cochrane Central Register of Controlled Trials was conducted. Two reviewers independently assessed each RCT for funding source, authors' FCOI(s), study characteristics, reporting of methodological measures important for internal validity and outcome (positive [statistically significant result favoring experimental drug for the primary outcome] or non-positive). Forty-seven RCTs were eligible with funding source as: 26 (55.3%) industry; eight (17%) non-profit source(s); five (10.6%) mixed; and eight (17%) unspecified. Industry-funded RCTs were more likely to be multicenter and enroll greater number of patients. Reporting of key methodological measures was suboptimal; however, industry and non-profit funded RCTs did not differ in their reporting. Thirty (63.8%) RCTs had ≥ one author who disclosed an FCOI (receipt of research grant [21, 44.7%], industry sponsor employee [20, 42.6%], receipt of consultancy fee/honorarium [16, 34%] and stock ownership [11, 23.4%]). Although industry funding and certain authors' FCOIs (employment and receipt of consultancy fee/honorarium) were univariately associated with positive outcome, such association was not observed after adjusting for study sample size. The majority of FM-RCTs were industry-sponsored, and had at least one author with an FCOI. Reporting of key methodological measures was suboptimal. After adjusting for study sample size, no association of industry funding or author's FCOI with study outcome was seen. © 2015 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

How to combine probabilistic and fuzzy uncertainties in fuzzy control

NASA Technical Reports Server (NTRS)

Nguyen, Hung T.; Kreinovich, Vladik YA.; Lea, Robert

1991-01-01

Fuzzy control is a methodology that translates natural-language rules, formulated by expert controllers, into the actual control strategy that can be implemented in an automated controller. In many cases, in addition to the experts' rules, additional statistical information about the system is known. It is explained how to use this additional information in fuzzy control methodology.

Association between long travel and venous thromboembolic disease: a systematic review and meta-analysis of case-control studies

PubMed Central

Jiménez-Puente, Alberto; Perea-Milla, Emilio

2007-01-01

The term “economy-class syndrome” defines an infrequent episode of venous thromboembolism (VTED) related to a long travel, namely by plane. However, this relation has not clearly been demonstrated by investigators. We carried out a systematic review and a meta-analysis of cases-control studies that had studied this topic. We realised a systematic review of the literature and selected all the case-control studies published. Two authors carried out a methodological evaluation according to the Scottish Intercollegiate Guidelines Network items (concordance was analysed by weighted kappa index), and a systematic analysis of the potential biases of each study was assessed. We carried out the meta-analysis with the data extracted from the studies. We recovered eight cases-control studies. The relation between the antecedent of a long travel and subsequent VTED varied from OR = 1.1 to OR = 4.0 and was found to be significant in four studies. The studies were highly heterogeneous in methodology and so the results obtained about the relation between the long travel and the VTED and the score at SIGN50. Two meta-analysis were carried out: only with travels by plane in which the relation was not significant (OR = 1.21; CI 95%, 0.95–1.55) and with all types of transport, with a slightly significant relation (OR = 1.46; CI95%, 1.24–1.72). We may deduce from this systematic review that there does exist a weak association between episodes of VTED and a long travel, but not by plane specifically. The heterogeneity and the methodological quality of the studies published preclude of more robust conclusions. PMID:17899081

A combined stochastic feedforward and feedback control design methodology with application to autoland design

NASA Technical Reports Server (NTRS)

Halyo, Nesim

1987-01-01

A combined stochastic feedforward and feedback control design methodology was developed. The objective of the feedforward control law is to track the commanded trajectory, whereas the feedback control law tries to maintain the plant state near the desired trajectory in the presence of disturbances and uncertainties about the plant. The feedforward control law design is formulated as a stochastic optimization problem and is embedded into the stochastic output feedback problem where the plant contains unstable and uncontrollable modes. An algorithm to compute the optimal feedforward is developed. In this approach, the use of error integral feedback, dynamic compensation, control rate command structures are an integral part of the methodology. An incremental implementation is recommended. Results on the eigenvalues of the implemented versus designed control laws are presented. The stochastic feedforward/feedback control methodology is used to design a digital automatic landing system for the ATOPS Research Vehicle, a Boeing 737-100 aircraft. The system control modes include localizer and glideslope capture and track, and flare to touchdown. Results of a detailed nonlinear simulation of the digital control laws, actuator systems, and aircraft aerodynamics are presented.

Children's construction task performance and spatial ability: controlling task complexity and predicting mathematics performance.

PubMed

Richardson, Miles; Hunt, Thomas E; Richardson, Cassandra

2014-12-01

This paper presents a methodology to control construction task complexity and examined the relationships between construction performance and spatial and mathematical abilities in children. The study included three groups of children (N = 96); ages 7-8, 10-11, and 13-14 years. Each group constructed seven pre-specified objects. The study replicated and extended previous findings that indicated that the extent of component symmetry and variety, and the number of components for each object and available for selection, significantly predicted construction task difficulty. Results showed that this methodology is a valid and reliable technique for assessing and predicting construction play task difficulty. Furthermore, construction play performance predicted mathematical attainment independently of spatial ability.

A system and methodology for measuring volatile organic compounds produced by hydroponic lettuce in a controlled environment

NASA Technical Reports Server (NTRS)

Charron, C. S.; Cantliffe, D. J.; Wheeler, R. M.; Manukian, A.; Heath, R. R.

1996-01-01

A system and methodology were developed for the nondestructive qualitative and quantitative analysis of volatile emissions from hydroponically grown 'Waldmann's Green' leaf lettuce (Lactuca sativa L.). Photosynthetic photon flux (PPF), photoperiod, and temperature were automatically controlled and monitored in a growth chamber modified for the collection of plant volatiles. The lipoxygenase pathway products (Z)-3-hexenal, (Z)-3-hexenol, and (Z)-3-hexenyl acetate were emitted by lettuce plants after the transition from the light period to the dark period. The volatile collection system developed in this study enabled measurements of volatiles emitted by intact plants, from planting to harvest, under controlled environmental conditions.

Gaming Space: A Game-Theoretic Methodology for Assessing the Deterrent Value of Space Control Options

DTIC Science & Technology

2018-06-07

Gaming Space A Game-Theoretic Methodology for Assessing the Deterrent Value of Space Control Options C O R...in space. Adversaries have already employed non -kinetic OSC capabilities, such as Global Positioning System jammers, in recent conflicts, and they...as part of the project “Assessing the Deterrent Value of Defensive Space Control Options.” The purpose of the project was to develop a methodology

Education in cardiopulmonary resuscitation in Russia: A systematic review of the available evidence

PubMed Central

Birkun, Alexei; Glotov, Maksim

2017-01-01

BACKGROUND: To summarise and appraise cumulative published scientific evidence relevant to cardiopulmonary resuscitation (CPR) education in Russia. DATA RESOURCES: We searched Medline, Scopus, Science Direct and Russian Science Citation Index databases from December 1991 to December 2016 to identify studies pertaining to the field of CPR education that were carried out by Russian researchers and/or investigated the topic of interest for Russia/Russian population. Reference lists of eligible publications, contents pages of relevant Russian journals and Google Scholar were also searched. There was no limitation based on publication language or study design. RESULTS: Of 7 964 unique citations identified, 22 studies were included. All studies were published from 2009 to 2016, mainly in Russian. Only three studies were reported to be randomized controlled. Non-medical individuals constituted 17% of studied populations. Most of the studies aimed to assess effects of CPR educational interventions, generally suggesting positive influence of the training conducted. The studies were highly heterogeneous as for methodological approaches, structure and duration of educational interventions, evaluation methods and criteria being used. Methodological quality was generally poor, with >40% publications not passing quality screening and only 2 studies meeting the criteria of moderate high quality. CONCLUSION: The results suggest paucity, low population coverage, high thematic and methodological heterogeneity and low quality of the studies addressing CPR education, which were carried out in the Russian Federation. There is a critical need in conducting methodologically consistent, large-scale, randomized, controlled studies evaluating and comparing efficiency of educational interventions for teaching CPR in different population categories of Russia. PMID:29123601

The design and methodology of premature ejaculation interventional studies

PubMed Central

2016-01-01

Large well-designed clinical efficacy and safety randomized clinical trials (RCTs) are required to achieve regulatory approval of new drug treatments. The objective of this article is to make recommendations for the criteria for defining and selecting the clinical trial study population, design and efficacy outcomes measures which comprise ideal premature ejaculation (PE) interventional trial methodology. Data on clinical trial design, epidemiology, definitions, dimensions and psychological impact of PE was reviewed, critiqued and incorporated into a series of recommendations for standardisation of PE clinical trial design, outcome measures and reporting using the principles of evidence based medicine. Data from PE interventional studies are only reliable, interpretable and capable of being generalised to patients with PE, when study populations are defined by the International Society for Sexual Medicine (ISSM) multivariate definition of PE. PE intervention trials should employ a double-blind RCT methodology and include placebo control, active standard drug control, and/or dose comparison trials. Ejaculatory latency time (ELT) and subject/partner outcome measures of control, personal/partner/relationship distress and other study-specific outcome measures should be used as outcome measures. There is currently no published literature which identifies a clinically significant threshold response to intervention. The ISSM definition of PE reflects the contemporary understanding of PE and represents the state-of-the-art multi-dimensional definition of PE and is recommended as the basis of diagnosis of PE for all PE clinical trials. PMID:27652224

Mixed methods research in tobacco control with youth and young adults: A methodological review of current strategies.

PubMed

Fryer, Craig S; Seaman, Elizabeth L; Clark, Rachael S; Plano Clark, Vicki L

2017-01-01

Tobacco use among young people is a complex and serious global dilemma that demands innovative and diverse research approaches. The purpose of this methodological review was to examine the current use of mixed methods research in tobacco control with youth and young adult populations and to develop practical recommendations for tobacco control researchers interested in this methodology. Using PubMed, we searched five peer-reviewed journals that publish tobacco control empirical literature for the use of mixed methods research to study young populations, age 12-25 years. Our team analyzed the features of each article in terms of tobacco control topic, population, youth engagement strategies, and several essential elements of mixed methods research. We identified 23 mixed methods studies published by authors from five different countries reported between 2004 and 2015. These 23 articles examined various topics that included tobacco use behavior, tobacco marketing and branding, and cessation among youth and young adults. The most common mixed methods approach was variations of the concurrent design in which the qualitative and quantitative strands were administered at the same time and given equal priority. This review documented several innovative applications of mixed methods research as well as challenges in the reporting of the complex research designs. The use of mixed methods research in tobacco control has great potential for advancing the understanding of complex behavioral and sociocultural issues for all groups, especially youth and young adults.

Mixed methods research in tobacco control with youth and young adults: A methodological review of current strategies

PubMed Central

Seaman, Elizabeth L.; Clark, Rachael S.; Plano Clark, Vicki L.

2017-01-01

Introduction Tobacco use among young people is a complex and serious global dilemma that demands innovative and diverse research approaches. The purpose of this methodological review was to examine the current use of mixed methods research in tobacco control with youth and young adult populations and to develop practical recommendations for tobacco control researchers interested in this methodology. Methods Using PubMed, we searched five peer-reviewed journals that publish tobacco control empirical literature for the use of mixed methods research to study young populations, age 12–25 years. Our team analyzed the features of each article in terms of tobacco control topic, population, youth engagement strategies, and several essential elements of mixed methods research. Results We identified 23 mixed methods studies published by authors from five different countries reported between 2004 and 2015. These 23 articles examined various topics that included tobacco use behavior, tobacco marketing and branding, and cessation among youth and young adults. The most common mixed methods approach was variations of the concurrent design in which the qualitative and quantitative strands were administered at the same time and given equal priority. This review documented several innovative applications of mixed methods research as well as challenges in the reporting of the complex research designs. Conclusions The use of mixed methods research in tobacco control has great potential for advancing the understanding of complex behavioral and sociocultural issues for all groups, especially youth and young adults. PMID:28841689

Multi-Time Step Service Restoration for Advanced Distribution Systems and Microgrids

DOE PAGES

Chen, Bo; Chen, Chen; Wang, Jianhui; ...

2017-07-07

Modern power systems are facing increased risk of disasters that can cause extended outages. The presence of remote control switches (RCSs), distributed generators (DGs), and energy storage systems (ESS) provides both challenges and opportunities for developing post-fault service restoration methodologies. Inter-temporal constraints of DGs, ESS, and loads under cold load pickup (CLPU) conditions impose extra complexity on problem formulation and solution. In this paper, a multi-time step service restoration methodology is proposed to optimally generate a sequence of control actions for controllable switches, ESSs, and dispatchable DGs to assist the system operator with decision making. The restoration sequence is determinedmore » to minimize the unserved customers by energizing the system step by step without violating operational constraints at each time step. The proposed methodology is formulated as a mixed-integer linear programming (MILP) model and can adapt to various operation conditions. Furthermore, the proposed method is validated through several case studies that are performed on modified IEEE 13-node and IEEE 123-node test feeders.« less

Multi-Time Step Service Restoration for Advanced Distribution Systems and Microgrids

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

Chen, Bo; Chen, Chen; Wang, Jianhui

Modern power systems are facing increased risk of disasters that can cause extended outages. The presence of remote control switches (RCSs), distributed generators (DGs), and energy storage systems (ESS) provides both challenges and opportunities for developing post-fault service restoration methodologies. Inter-temporal constraints of DGs, ESS, and loads under cold load pickup (CLPU) conditions impose extra complexity on problem formulation and solution. In this paper, a multi-time step service restoration methodology is proposed to optimally generate a sequence of control actions for controllable switches, ESSs, and dispatchable DGs to assist the system operator with decision making. The restoration sequence is determinedmore » to minimize the unserved customers by energizing the system step by step without violating operational constraints at each time step. The proposed methodology is formulated as a mixed-integer linear programming (MILP) model and can adapt to various operation conditions. Furthermore, the proposed method is validated through several case studies that are performed on modified IEEE 13-node and IEEE 123-node test feeders.« less

Application of hybrid methodology to rotors in steady and maneuvering flight

NASA Astrophysics Data System (ADS)

Rajmohan, Nischint

Helicopters are versatile flying machines that have capabilities that are unparalleled by fixed wing aircraft, such as operating in hover, performing vertical takeoff and landing on unprepared sites. This makes their use especially desirable in military and search-and-rescue operations. However, modern helicopters still suffer from high levels of noise and vibration caused by the physical phenomena occurring in the vicinity of the rotor blades. Therefore, improvement in rotorcraft design to reduce the noise and vibration levels requires understanding of the underlying physical phenomena, and accurate prediction capabilities of the resulting rotorcraft aeromechanics. The goal of this research is to study the aeromechanics of rotors in steady and maneuvering flight using hybrid Computational Fluid Dynamics (CFD) methodology. The hybrid CFD methodology uses the Navier-Stokes equations to solve the flow near the blade surface but the effect of the far wake is computed through the wake model. The hybrid CFD methodology is computationally efficient and its wake modeling approach is nondissipative making it an attractive tool to study rotorcraft aeromechanics. Several enhancements were made to the CFD methodology and it was coupled to a Computational Structural Dynamics (CSD) methodology to perform a trimmed aeroelastic analysis of a rotor in forward flight. The coupling analyses, both loose and tight were used to identify the key physical phenomena that affect rotors in different steady flight regimes. The modeling enhancements improved the airloads predictions for a variety of flight conditions. It was found that the tightly coupled method did not impact the loads significantly for steady flight conditions compared to the loosely coupled method. The coupling methodology was extended to maneuvering flight analysis by enhancing the computational and structural models to handle non-periodic flight conditions and vehicle motions in time accurate mode. The flight test control angles were employed to enable the maneuvering flight analysis. The fully coupled model provided the presence of three dynamic stall cycles on the rotor in maneuver. It is important to mention that analysis of maneuvering flight requires knowledge of the pilot input control pitch settings, and the vehicle states. As the result, these computational tools cannot be used for analysis of loads in a maneuver that has not been duplicated in a real flight. This is a significant limitation if these tools are to be selected during the design phase of a helicopter where its handling qualities are evaluated in different trajectories. Therefore, a methodology was developed to couple the CFD/CSD simulation with an inverse flight mechanics simulation to perform the maneuver analysis without using the flight test control input. The methodology showed reasonable convergence in steady flight regime and control angles predictions compared fairly well with test data. In the maneuvering flight regions, the convergence was slower due to relaxation techniques used for the numerical stability. The subsequent computed control angles for the maneuvering flight regions compared well with test data. Further, the enhancement of the rotor inflow computations in the inverse simulation through implementation of a Lagrangian wake model improved the convergence of the coupling methodology.

Performance-Driven Hybrid Full-Body Character Control for Navigation and Interaction in Virtual Environments

NASA Astrophysics Data System (ADS)

Mousas, Christos; Anagnostopoulos, Christos-Nikolaos

2017-06-01

This paper presents a hybrid character control interface that provides the ability to synthesize in real-time a variety of actions based on the user's performance capture. The proposed methodology enables three different performance interaction modules: the performance animation control that enables the direct mapping of the user's pose to the character, the motion controller that synthesizes the desired motion of the character based on an activity recognition methodology, and the hybrid control that lies within the performance animation and the motion controller. With the methodology presented, the user will have the freedom to interact within the virtual environment, as well as the ability to manipulate the character and to synthesize a variety of actions that cannot be performed directly by him/her, but which the system synthesizes. Therefore, the user is able to interact with the virtual environment in a more sophisticated fashion. This paper presents examples of different scenarios based on the three different full-body character control methodologies.

The Impact of Prenatal Parental Locus of Control on Children's Psychological Outcomes in Infancy and Early Childhood: A Prospective 5 Year Study

PubMed Central

Nowicki, Stephen; Iles-Caven, Yasmin; Gregory, Steven; Ellis, Genette; Golding, Jean

2017-01-01

Locus of control is one of the most widely studied concepts in the history of personality psychology. In spite of its popularity and its associations with numerous relevant outcomes, the ability of locus of control to predict future behaviors involving parenting effectiveness has been under researched. The few parent locus of control children's outcome studies are characterized by cross-sectional methodologies that focus on mothers. The present study uses a prospective methodology to compare data on mothers' and fathers' locus of control with their child's behavior outcomes from a large scale research project, the Avon Longitudinal Study of Parents and Children (ALSPAC). Based on Rotter's Social Learning Theory published in 1954 and past empirical research, it was predicted and found that parent internality was associated with more positive child outcomes than parent externality. More specifically, when both parents were internal, their children had more positive outcomes in sleeping, eating, and tantrum behavior as compared to any other parent locus of control combination. However external parents had a less restrictive attitude which appeared to have a more beneficial effect on picky eating. Results confirmed how important parent locus of control is in the lives of children. Based on the findings, researchers are urged to develop interventions to change advice to parents and promote more internal locus of control among parents. PMID:28446887

Methodological Issues in Research on Web-Based Behavioral Interventions

PubMed Central

Danaher, Brian G; Seeley, John R

2013-01-01

Background Web-based behavioral intervention research is rapidly growing. Purpose We review methodological issues shared across Web-based intervention research to help inform future research in this area. Methods We examine measures and their interpretation using exemplar studies and our research. Results We report on research designs used to evaluate Web-based interventions and recommend newer, blended designs. We review and critique methodological issues associated with recruitment, engagement, and social validity. Conclusions We suggest that there is value to viewing this burgeoning realm of research from the broader context of behavior change research. We conclude that many studies use blended research designs, that innovative mantling designs such as the Multiphase Optimization Strategy and Sequential Multiple Assignment Randomized Trial methods hold considerable promise and should be used more widely, and that Web-based controls should be used instead of usual care or no-treatment controls in public health research. We recommend topics for future research that address participant recruitment, engagement, and social validity. PMID:19806416

Risk assessment of oil and gas well drilling activities in Iran - a case study: human factors.

PubMed

Amir-Heidari, Payam; Farahani, Hadi; Ebrahemzadih, Mehrzad

2015-01-01

Oil and gas well drilling activities are associated with numerous hazards which have the potential to cause injury or harm for people, property and the environment. These hazards are also a threat for the reputation of drilling companies. To prevent accidents and undesired events in drilling operations it is essential to identify, evaluate, assess and control the attendant risks. In this work, a structured methodology is proposed for risk assessment of drilling activities. A case study is performed to identify, analyze and assess the risks arising from human factors in one of the on shore drilling sites in southern Iran. A total of 17 major hazards were identified and analyzed using the proposed methodology. The results showed that the residual risks of 100% of these hazards were in the acceptable or transitional zone, and their levels were expected to be lowered further by proper controls. This structured methodology may also be used in other drilling sites and companies for assessing the risks.

Identifying Items to Assess Methodological Quality in Physical Therapy Trials: A Factor Analysis

PubMed Central

Cummings, Greta G.; Fuentes, Jorge; Saltaji, Humam; Ha, Christine; Chisholm, Annabritt; Pasichnyk, Dion; Rogers, Todd

2014-01-01

Background Numerous tools and individual items have been proposed to assess the methodological quality of randomized controlled trials (RCTs). The frequency of use of these items varies according to health area, which suggests a lack of agreement regarding their relevance to trial quality or risk of bias. Objective The objectives of this study were: (1) to identify the underlying component structure of items and (2) to determine relevant items to evaluate the quality and risk of bias of trials in physical therapy by using an exploratory factor analysis (EFA). Design A methodological research design was used, and an EFA was performed. Methods Randomized controlled trials used for this study were randomly selected from searches of the Cochrane Database of Systematic Reviews. Two reviewers used 45 items gathered from 7 different quality tools to assess the methodological quality of the RCTs. An exploratory factor analysis was conducted using the principal axis factoring (PAF) method followed by varimax rotation. Results Principal axis factoring identified 34 items loaded on 9 common factors: (1) selection bias; (2) performance and detection bias; (3) eligibility, intervention details, and description of outcome measures; (4) psychometric properties of the main outcome; (5) contamination and adherence to treatment; (6) attrition bias; (7) data analysis; (8) sample size; and (9) control and placebo adequacy. Limitation Because of the exploratory nature of the results, a confirmatory factor analysis is needed to validate this model. Conclusions To the authors' knowledge, this is the first factor analysis to explore the underlying component items used to evaluate the methodological quality or risk of bias of RCTs in physical therapy. The items and factors represent a starting point for evaluating the methodological quality and risk of bias in physical therapy trials. Empirical evidence of the association among these items with treatment effects and a confirmatory factor analysis of these results are needed to validate these items. PMID:24786942

Identifying items to assess methodological quality in physical therapy trials: a factor analysis.

PubMed

Armijo-Olivo, Susan; Cummings, Greta G; Fuentes, Jorge; Saltaji, Humam; Ha, Christine; Chisholm, Annabritt; Pasichnyk, Dion; Rogers, Todd

2014-09-01

Numerous tools and individual items have been proposed to assess the methodological quality of randomized controlled trials (RCTs). The frequency of use of these items varies according to health area, which suggests a lack of agreement regarding their relevance to trial quality or risk of bias. The objectives of this study were: (1) to identify the underlying component structure of items and (2) to determine relevant items to evaluate the quality and risk of bias of trials in physical therapy by using an exploratory factor analysis (EFA). A methodological research design was used, and an EFA was performed. Randomized controlled trials used for this study were randomly selected from searches of the Cochrane Database of Systematic Reviews. Two reviewers used 45 items gathered from 7 different quality tools to assess the methodological quality of the RCTs. An exploratory factor analysis was conducted using the principal axis factoring (PAF) method followed by varimax rotation. Principal axis factoring identified 34 items loaded on 9 common factors: (1) selection bias; (2) performance and detection bias; (3) eligibility, intervention details, and description of outcome measures; (4) psychometric properties of the main outcome; (5) contamination and adherence to treatment; (6) attrition bias; (7) data analysis; (8) sample size; and (9) control and placebo adequacy. Because of the exploratory nature of the results, a confirmatory factor analysis is needed to validate this model. To the authors' knowledge, this is the first factor analysis to explore the underlying component items used to evaluate the methodological quality or risk of bias of RCTs in physical therapy. The items and factors represent a starting point for evaluating the methodological quality and risk of bias in physical therapy trials. Empirical evidence of the association among these items with treatment effects and a confirmatory factor analysis of these results are needed to validate these items. © 2014 American Physical Therapy Association.

Lateral stability analysis for X-29A drop model using system identification methodology

NASA Technical Reports Server (NTRS)

Raney, David L.; Batterson, James G.

1989-01-01

A 22-percent dynamically scaled replica of the X-29A forward-swept-wing airplane has been flown in radio-controlled drop tests at the NASA Langley Research Center. A system identification study of the recorded data was undertaken to examine the stability and control derivatives that influence the lateral behavior of this vehicle with particular emphasis on an observed wing rock phenomenon. All major lateral stability derivatives and the damping-in-roll derivative were identified for angles of attack from 5 to 80 degrees by using a data-partitioning methodology and a modified stepwise regression algorithm.

Proceedings of the Workshop on Identification and Control of Flexible Space Structures, volume 1

NASA Technical Reports Server (NTRS)

Rodriguez, G. (Editor)

1985-01-01

Identification and control of flexible space structures were studied. Exploration of the most advanced modeling estimation, identification and control methodologies to flexible space structures was discussed. The following general areas were discussed: space platforms, antennas, and flight experiments; control/structure interactions - modeling, integrated design and optimization, control and stabilization, and shape control; control technology; control of space stations; large antenna control, dynamics and control experiments, and control/structure interaction experiments.

Selecting a software development methodology. [of digital flight control systems

NASA Technical Reports Server (NTRS)

Jones, R. E.

1981-01-01

The state of the art analytical techniques for the development and verification of digital flight control software is studied and a practical designer oriented development and verification methodology is produced. The effectiveness of the analytic techniques chosen for the development and verification methodology are assessed both technically and financially. Technical assessments analyze the error preventing and detecting capabilities of the chosen technique in all of the pertinent software development phases. Financial assessments describe the cost impact of using the techniques, specifically, the cost of implementing and applying the techniques as well as the relizable cost savings. Both the technical and financial assessment are quantitative where possible. In the case of techniques which cannot be quantitatively assessed, qualitative judgements are expressed about the effectiveness and cost of the techniques. The reasons why quantitative assessments are not possible will be documented.

Assessing the risk of bias in randomized controlled trials in the field of dentistry indexed in the Lilacs (Literatura Latino-Americana e do Caribe em Ciências da Saúde) database.

PubMed

Ferreira, Christiane Alves; Loureiro, Carlos Alfredo Salles; Saconato, Humberto; Atallah, Alvaro Nagib

2011-03-01

Well-conducted randomized controlled trials (RCTs) represent the highest level of evidence when the research question relates to the effect of therapeutic or preventive interventions. However, the degree of control over bias between RCTs presents great variability between studies. For this reason, with the increasing interest in and production of systematic reviews and meta-analyses, it has been necessary to develop methodology supported by empirical evidence, so as to encourage and enhance the production of valid RCTs with low risk of bias. The aim here was to conduct a methodological analysis within the field of dentistry, regarding the risk of bias in open-access RCTs available in the Lilacs (Literatura Latino-Americana e do Caribe em Ciências da Saúde) database. This was a methodology study conducted at Universidade Federal de São Paulo (Unifesp) that assessed the risk of bias in RCTs, using the following dimensions: allocation sequence generation, allocation concealment, blinding, and data on incomplete outcomes. Out of the 4,503 articles classified, only 10 studies (0.22%) were considered to be true RCTs and, of these, only a single study was classified as presenting low risk of bias. The items that the authors of these RCTs most frequently controlled for were blinding and data on incomplete outcomes. The effective presence of bias seriously weakened the reliability of the results from the dental studies evaluated, such that they would be of little use for clinicians and administrators as support for decision-making processes.

Nonlinear Performance Seeking Control using Fuzzy Model Reference Learning Control and the Method of Steepest Descent

NASA Technical Reports Server (NTRS)

Kopasakis, George

1997-01-01

Performance Seeking Control (PSC) attempts to find and control the process at the operating condition that will generate maximum performance. In this paper a nonlinear multivariable PSC methodology will be developed, utilizing the Fuzzy Model Reference Learning Control (FMRLC) and the method of Steepest Descent or Gradient (SDG). This PSC control methodology employs the SDG method to find the operating condition that will generate maximum performance. This operating condition is in turn passed to the FMRLC controller as a set point for the control of the process. The conventional SDG algorithm is modified in this paper in order for convergence to occur monotonically. For the FMRLC control, the conventional fuzzy model reference learning control methodology is utilized, with guidelines generated here for effective tuning of the FMRLC controller.

Evaluating Multi-Input/Multi-Output Digital Control Systems

NASA Technical Reports Server (NTRS)

Pototzky, Anthony S.; Wieseman, Carol D.; Hoadley, Sherwood T.; Mukhopadhyay, Vivek

1994-01-01

Controller-performance-evaluation (CPE) methodology for multi-input/multi-output (MIMO) digital control systems developed. Procedures identify potentially destabilizing controllers and confirm satisfactory performance of stabilizing ones. Methodology generic and used in many types of multi-loop digital-controller applications, including digital flight-control systems, digitally controlled spacecraft structures, and actively controlled wind-tunnel models. Also applicable to other complex, highly dynamic digital controllers, such as those in high-performance robot systems.

An Analysis of the Relationship of Teaching Methodology and the Students' Level of Cognition with Student Achievement in Principles of Marketing.

ERIC Educational Resources Information Center

Hallgren, Kenneth Glenn

A study investigated the relationship of students' cognitive level of development and teaching methodology with student achievement. The sample was composed of 79 students in two sections of the introductory marketing course at the University of Northern Colorado. The control group was taught by a lecture strategy, and the experimental group by a…

The Utility of Conflict Resolution and Study Skills Interventions with Middle School Students at Risk for Antisocial Behavior: A Methodological Illustration

ERIC Educational Resources Information Center

Kalberg, Jemma Robertson; Lane, Kathleen; Lambert, Warren

2012-01-01

This article provides a methodological illustration of how to conduct randomized controls trials (RCT) for secondary levels of prevention within the context of three-tiered models of support. First, the authors demonstrate one method of using school-wide data to identify middle school students (N = 45) who were struggling in academic and…

Development and testing of controller performance evaluation methodology for multi-input/multi-output digital control systems

NASA Technical Reports Server (NTRS)

Pototzky, Anthony; Wieseman, Carol; Hoadley, Sherwood Tiffany; Mukhopadhyay, Vivek

1991-01-01

Described here is the development and implementation of on-line, near real time controller performance evaluation (CPE) methods capability. Briefly discussed are the structure of data flow, the signal processing methods used to process the data, and the software developed to generate the transfer functions. This methodology is generic in nature and can be used in any type of multi-input/multi-output (MIMO) digital controller application, including digital flight control systems, digitally controlled spacecraft structures, and actively controlled wind tunnel models. Results of applying the CPE methodology to evaluate (in near real time) MIMO digital flutter suppression systems being tested on the Rockwell Active Flexible Wing (AFW) wind tunnel model are presented to demonstrate the CPE capability.

How effective is drug testing as a workplace safety strategy? A systematic review of the evidence.

PubMed

Pidd, Ken; Roche, Ann M

2014-10-01

The growing prevalence of workplace drug testing and the narrow scope of previous reviews of the evidence base necessitate a comprehensive review of research concerning the efficacy of drug testing as a workplace strategy. A systematic qualitative review of relevant research published between January 1990 and January 2013 was undertaken. Inclusion criteria were studies that evaluated the effectiveness of drug testing in deterring employee drug use or reducing workplace accident or injury rates. Methodological adequacy was assessed using a published assessment tool specifically designed to assess the quality of intervention studies. A total of 23 studies were reviewed and assessed, six of which reported on the effectiveness of testing in reducing employee drug use and 17 which reported on occupational accident or injury rates. No studies involved randomised control trials. Only one study was assessed as demonstrating strong methodological rigour. That study found random alcohol testing reduced fatal accidents in the transport industry. The majority of studies reviewed contained methodological weaknesses including; inappropriate study design, limited sample representativeness, the use of ecological data to evaluate individual behaviour change and failure to adequately control for potentially confounding variables. This latter finding is consistent with previous reviews and indicates the evidence base for the effectiveness of testing in improving workplace safety is at best tenuous. Better dissemination of the current evidence in relation to workplace drug testing is required to support evidence-informed policy and practice. There is also a pressing need for more methodologically rigorous research to evaluate the efficacy and utility of drug testing. Copyright © 2014 Elsevier Ltd. All rights reserved.

Revisiting typhoid fever surveillance in low and middle income countries: lessons from systematic literature review of population-based longitudinal studies.

PubMed

Mogasale, Vittal; Mogasale, Vijayalaxmi V; Ramani, Enusa; Lee, Jung Seok; Park, Ju Yeon; Lee, Kang Sung; Wierzba, Thomas F

2016-01-29

The control of typhoid fever being an important public health concern in low and middle income countries, improving typhoid surveillance will help in planning and implementing typhoid control activities such as deployment of new generation Vi conjugate typhoid vaccines. We conducted a systematic literature review of longitudinal population-based blood culture-confirmed typhoid fever studies from low and middle income countries published from 1(st) January 1990 to 31(st) December 2013. We quantitatively summarized typhoid fever incidence rates and qualitatively reviewed study methodology that could have influenced rate estimates. We used meta-analysis approach based on random effects model in summarizing the hospitalization rates. Twenty-two papers presented longitudinal population-based and blood culture-confirmed typhoid fever incidence estimates from 20 distinct sites in low and middle income countries. The reported incidence and hospitalizations rates were heterogeneous as well as the study methodology across the sites. We elucidated how the incidence rates were underestimated in published studies. We summarized six categories of under-estimation biases observed in these studies and presented potential solutions. Published longitudinal typhoid fever studies in low and middle income countries are geographically clustered and the methodology employed has a potential for underestimation. Future studies should account for these limitations.

Self-Contained Automated Methodology for Optimal Flow Control

NASA Technical Reports Server (NTRS)

Joslin, Ronald D.; Gunzburger, Max D.; Nicolaides, Roy A.; Erlebacherl, Gordon; Hussaini, M. Yousuff

1997-01-01

This paper describes a self-contained, automated methodology for active flow control which couples the time-dependent Navier-Stokes system with an adjoint Navier-Stokes system and optimality conditions from which optimal states, i.e., unsteady flow fields and controls (e.g., actuators), may be determined. The problem of boundary layer instability suppression through wave cancellation is used as the initial validation case to test the methodology. Here, the objective of control is to match the stress vector along a portion of the boundary to a given vector; instability suppression is achieved by choosing the given vector to be that of a steady base flow. Control is effected through the injection or suction of fluid through a single orifice on the boundary. The results demonstrate that instability suppression can be achieved without any a priori knowledge of the disturbance, which is significant because other control techniques have required some knowledge of the flow unsteadiness such as frequencies, instability type, etc. The present methodology has been extended to three dimensions and may potentially be applied to separation control, re-laminarization, and turbulence control applications using one to many sensors and actuators.

Experimental validation of an integrated controls-structures design methodology for a class of flexible space structures

NASA Technical Reports Server (NTRS)

Maghami, Peiman G.; Gupta, Sandeep; Elliott, Kenny B.; Joshi, Suresh M.; Walz, Joseph E.

1994-01-01

This paper describes the first experimental validation of an optimization-based integrated controls-structures design methodology for a class of flexible space structures. The Controls-Structures-Interaction (CSI) Evolutionary Model, a laboratory test bed at Langley, is redesigned based on the integrated design methodology with two different dissipative control strategies. The redesigned structure is fabricated, assembled in the laboratory, and experimentally compared with the original test structure. Design guides are proposed and used in the integrated design process to ensure that the resulting structure can be fabricated. Experimental results indicate that the integrated design requires greater than 60 percent less average control power (by thruster actuators) than the conventional control-optimized design while maintaining the required line-of-sight performance, thereby confirming the analytical findings about the superiority of the integrated design methodology. Amenability of the integrated design structure to other control strategies is considered and evaluated analytically and experimentally. This work also demonstrates the capabilities of the Langley-developed design tool CSI DESIGN which provides a unified environment for structural and control design.

Understanding the metabolic and health effects of low-calorie sweeteners: methodological considerations and implications for future research

PubMed Central

Sylvetsky, Allison C.; Blau, Jenny E.; Rother, Kristina I.

2016-01-01

Consumption of foods, beverages, and packets containing low-calorie sweeteners (LCS) has increased markedly across gender, age, race/ethnicity, weight status, and socioeconomic subgroups. However, well-controlled intervention studies rigorously evaluating the health effects of LCS in humans are limited. One of the key questions is whether LCS are indeed a beneficial strategy for weight management and prevention of obesity. The current review discusses several methodological considerations in the design and interpretation of these studies. Specifically, we focus on the selection of study participants, inclusion of an appropriate control, importance of considering habitual LCS exposure, selection of specific LCS, dose and route of LCS administration, choice of study outcomes, and the context and generalizability of the study findings. These critical considerations will guide the design of future studies and thus assist in understanding the health effects of LCS. PMID:26936185

Understanding the metabolic and health effects of low-calorie sweeteners: methodological considerations and implications for future research.

PubMed

Sylvetsky, Allison C; Blau, Jenny E; Rother, Kristina I

2016-06-01

Consumption of foods, beverages, and packets containing low-calorie sweeteners (LCS) has increased markedly across gender, age, race/ethnicity, weight status, and socio-economic subgroups. However, well-controlled intervention studies rigorously evaluating the health effects of LCS in humans are limited. One of the key questions is whether LCS are indeed a beneficial strategy for weight management and prevention of obesity. The current review discusses several methodological considerations in the design and interpretation of these studies. Specifically, we focus on the selection of study participants, inclusion of an appropriate control, importance of considering habitual LCS exposure, selection of specific LCS, dose and route of LCS administration, choice of study outcomes, and the context and generalizability of the study findings. These critical considerations will guide the design of future studies and thus assist in understanding the health effects of LCS.

Hamstring autograft versus soft-tissue allograft in anterior cruciate ligament reconstruction: a systematic review and meta-analysis of randomized controlled trials.

PubMed

Cvetanovich, Gregory L; Mascarenhas, Randy; Saccomanno, Maristella F; Verma, Nikhil N; Cole, Brian J; Bush-Joseph, Charles A; Bach, Bernard R

2014-12-01

To compare outcomes of anterior cruciate ligament (ACL) reconstruction with hamstring autograft versus soft-tissue allograft by systematic review and meta-analysis. A systematic review of randomized controlled studies comparing hamstring autograft with soft-tissue allograft in ACL reconstruction was performed. Studies were identified by strict inclusion and exclusion criteria. Descriptive statistics were reported. Where possible, the data were pooled and a meta-analysis was performed using RevMan software (The Nordic Cochrane Centre, The Cochrane Collaboration, Copenhagen, Denmark). Dichotomous data were reported as risk ratios, whereas continuous data were reported as standardized mean differences and 95% confidence intervals. Heterogeneity was assessed by use of I(2) for each meta-analysis. Study methodologic quality was analyzed with the Modified Coleman Methodology Score and Jadad scale. Five studies with 504 combined patients (251 autograft and 253 allograft; 374 male and 130 female patients) with a mean age of 29.9 ± 2.2 years were included. The allografts used were fresh-frozen hamstring, irradiated hamstring, mixture of fresh-frozen and cryopreserved hamstring, fresh-frozen tibialis anterior, and fresh-frozen Achilles tendon grafts without bone blocks. The mean follow-up period was 47.4 ± 26.9 months, with a mean follow-up rate of 83.3% ± 8.6%. Two studies found a longer operative time with autograft than with allograft (77.1 ± 2.0 minutes v 59.9 ± 0.9 minutes, P = .008). Meta-analysis showed no statistically significant differences between autografts and allografts for any outcome measures (P > .05 for all tests). One study found significantly greater laxity for irradiated allograft than for autograft. The methodologic quality of the 5 studies was poor, with a mean Modified Coleman Methodology Score of 54.4 ± 6.9 and mean Jadad score of 1.6 ± 1.5. On the basis of this systematic review and meta-analysis of 5 randomized controlled trials, there is no statistically significant difference in outcome between patients undergoing ACL reconstruction with hamstring autograft and those undergoing ACL reconstruction with soft-tissue allograft. These results may not extrapolate to younger patient populations. The methodology of the available randomized controlled trials comparing hamstring autograft and soft-tissue allograft is poor. Level II, systematic review of Level I and II studies. Copyright © 2014 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Effect of periodontal treatment on preterm birth rate: a systematic review of meta-analyses.

PubMed

López, Néstor J; Uribe, Sergio; Martinez, Benjamín

2015-02-01

Preterm birth is a major cause of neonatal morbidity and mortality in both developed and developing countries. Preterm birth is a highly complex syndrome that includes distinct clinical subtypes in which many different causes may be involved. The results of epidemiological, molecular, microbiological and animal-model studies support a positive association between maternal periodontal disease and preterm birth. However, the results of intervention studies carried out to determine the effect of periodontal treatment on reducing the risk of preterm birth are controversial. This systematic review critically analyzes the methodological issues of meta-analyses of the studies to determine the effect of periodontal treatment to reduce preterm birth. The quality of the individual randomized clinical trials selected is of highest relevance for a systematic review. This article describes the methodological features that should be identified a priori and assessed individually to determine the quality of a randomized controlled trial performed to evaluate the effect of periodontal treatment on pregnancy outcomes. The AMSTAR and the PRISMA checklist tools were used to assess the quality of the six meta-analyses selected, and the bias domain of the Cochrane Collaboration's Tool was applied to evaluate each of the trials included in the meta-analyses. In addition, the methodological characteristics of each clinical trial were assessed. The majority of the trials included in the meta-analyses have significant methodological flaws that threaten their internal validity. The lack of effect of periodontal treatment on preterm birth rate concluded by four meta-analyses, and the positive effect of treatment for reducing preterm birth risk concluded by the remaining two meta-analyses are not based on consistent scientific evidence. Well-conducted randomized controlled trials using rigorous methodology, including appropriate definition of the exposure, adequate control of confounders for preterm birth and application of effective periodontal interventions to eliminate periodontal infection, are needed to confirm the positive association between periodontal disease and preterm birth. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Range of control of cardiovascular variables by the hypothalamus

NASA Technical Reports Server (NTRS)

Smith, O. A.; Stephenson, R. B.; Randall, D. C.

1974-01-01

New methodologies were utilized to study the influence of the hypothalamus on the cardiovascular system. The regulation of myocardial activity was investigated in monkeys with hypothalamic lesions that eliminate cardiovascular responses. Observations showed that a specific part of the hypothalamus regulates changes in myocardial contractility that accompanies emotion. Studies of the hypothalamus control of renal blood flow showed the powerful potential control of this organ over renal circulation.

OPUS: Optimal Projection for Uncertain Systems. Volume 1

DTIC Science & Technology

1991-09-01

unifiedI control- design methodology that directly addresses these technology issues. 1 In particular, optimal projection theory addresses the need for...effects, and limited identification accuracy in a 1-g environment. The principal contribution of OPUS is a unified design methodology that...characterizing solutions to constrained control- design problems. Transforming OPUS into a practi- cal design methodology requires the development of

Optimal Micro-Jet Flow Control for Compact Air Vehicle Inlets

NASA Technical Reports Server (NTRS)

Anderson, Bernhard H.; Miller, Daniel N.; Addington, Gregory A.; Agrell, Johan

2004-01-01

The purpose of this study on micro-jet secondary flow control is to demonstrate the viability and economy of Response Surface Methodology (RSM) to optimally design micro-jet secondary flow control arrays, and to establish that the aeromechanical effects of engine face distortion can also be included in the design and optimization process. These statistical design concepts were used to investigate the design characteristics of "low mass" micro-jet array designs. The term "low mass" micro-jet may refers to fluidic jets with total (integrated) mass flow ratios between 0.10 and 1.0 percent of the engine face mass flow. Therefore, this report examines optimal micro-jet array designs for compact inlets through a Response Surface Methodology.

An Application of Six Sigma to Reduce Supplier Quality Cost

NASA Astrophysics Data System (ADS)

Gaikwad, Lokpriya Mohanrao; Teli, Shivagond Nagappa; Majali, Vijay Shashikant; Bhushi, Umesh Mahadevappa

2016-01-01

This article presents an application of Six Sigma to reduce supplier quality cost in manufacturing industry. Although there is a wider acceptance of Six Sigma in many organizations today, there is still a lack of in-depth case study of Six Sigma. For the present research the case study methodology was used. The company decided to reduce quality cost and improve selected processes using Six Sigma methodologies. Regarding the fact that there is a lack of case studies dealing with Six Sigma especially in individual manufacturing organization this article could be of great importance also for the practitioners. This paper discusses the quality and productivity improvement in a supplier enterprise through a case study. The paper deals with an application of Six Sigma define-measure-analyze-improve-control methodology in an industry which provides a framework to identify, quantify and eliminate sources of variation in an operational process in question, to optimize the operation variables, improve and sustain performance viz. process yield with well-executed control plans. Six Sigma improves the process performance (process yield) of the critical operational process, leading to better utilization of resources, decreases variations and maintains consistent quality of the process output.

Anti-tobacco mass media and socially disadvantaged groups: a systematic and methodological review.

PubMed

Guillaumier, Ashleigh; Bonevski, Billie; Paul, Chris

2012-07-01

Only a limited amount of research has been conducted to explore whether there are socioeconomic status differences in responses to mass media. However, the methodological quality of this evidence has not been assessed, limiting confidence in conclusions that can be drawn regarding study outcomes. A systematic review of the effectiveness of anti-tobacco mass media campaigns with socially disadvantaged groups was conducted, and the methodological quality of included studies was assessed. Medline, The Cochrane Library, PsycInfo, Embase and Web of Science were searched using MeSH and keywords for quantitative studies conducted in Western countries prior to March 2012. A methodological quality assessment and narrative analysis of included studies was undertaken. Seventeen relevant studies (reported in 18 papers) were identified; however, weak study designs and selection bias were common characteristics, limiting strong conclusions about effectiveness. Using predominantly non-cessation related outcome measures reviewed papers indicated mixed results for mass media tobacco control campaign effectiveness among various social groups. Most studies assessed mass media impact on low socioeconomic status groups rather than highly socially disadvantaged groups. Methodological rigour of evaluations in this field must be improved to aid understanding regarding the effectiveness of mass media campaigns in driving cessation among disadvantaged groups. The results of this review indicate a gap in methodologically rigorous research into the effectiveness of mass media campaigns among socially disadvantaged groups, particularly the highly disadvantaged. © 2012 Australasian Professional Society on Alcohol and other Drugs.

Current Evidence on Heart Rate Variability Biofeedback as a Complementary Anticraving Intervention.

PubMed

Alayan, Nour; Eller, Lucille; Bates, Marsha E; Carmody, Dennis P

2018-05-21

The limited success of conventional anticraving interventions encourages research into new treatment strategies. Heart rate variability biofeedback (HRVB), which is based on slowed breathing, was shown to improve symptom severity in various disorders. HRVB, and certain rates of controlled breathing (CB), may offer therapeutic potential as a complementary drug-free treatment option to help control substance craving. This review evaluated current evidence on the effectiveness of HRVB and CB training as a complementary anticraving intervention, based on guidelines from the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols. Studies that assessed a cardiorespiratory feedback or CB intervention with substance craving as an outcome were selected. Effect sizes were calculated for each study. The Scale for Assessing Scientific Quality of Investigations in Complementary and Alternative Medicine was used to evaluate the quality of each study reviewed. A total of eight articles remained for final review, including controlled studies with or without randomization, as well as noncontrolled trials. Most studies showed positive results with a variety of methodological quality levels and effect size. Current HRVB studies rated moderately on methodological rigor and showed inconsistent magnitudes of calculated effect size (0.074-0.727) across populations. The largest effect size was found in a nonclinical college population of high food cravers utilizing the most intensive HRVB training time of 240 min. Despite the limitations of this review, there is beginning evidence that HRVB and CB training can be of significant therapeutic potential. Larger clinical trials are needed with methodological improvements such as longer treatment duration, adequate control conditions, measures of adherence and compliance, longitudinal examination of craving changes, and more comprehensive methods of craving measurement.

Online intelligent controllers for an enzyme recovery plant: design methodology and performance.

PubMed

Leite, M S; Fujiki, T L; Silva, F V; Fileti, A M F

2010-12-27

This paper focuses on the development of intelligent controllers for use in a process of enzyme recovery from pineapple rind. The proteolytic enzyme bromelain (EC 3.4.22.4) is precipitated with alcohol at low temperature in a fed-batch jacketed tank. Temperature control is crucial to avoid irreversible protein denaturation. Fuzzy or neural controllers offer a way of implementing solutions that cover dynamic and nonlinear processes. The design methodology and a comparative study on the performance of fuzzy-PI, neurofuzzy, and neural network intelligent controllers are presented. To tune the fuzzy PI Mamdani controller, various universes of discourse, rule bases, and membership function support sets were tested. A neurofuzzy inference system (ANFIS), based on Takagi-Sugeno rules, and a model predictive controller, based on neural modeling, were developed and tested as well. Using a Fieldbus network architecture, a coolant variable speed pump was driven by the controllers. The experimental results show the effectiveness of fuzzy controllers in comparison to the neural predictive control. The fuzzy PI controller exhibited a reduced error parameter (ITAE), lower power consumption, and better recovery of enzyme activity.

Online Intelligent Controllers for an Enzyme Recovery Plant: Design Methodology and Performance

PubMed Central

Leite, M. S.; Fujiki, T. L.; Silva, F. V.; Fileti, A. M. F.

2010-01-01

This paper focuses on the development of intelligent controllers for use in a process of enzyme recovery from pineapple rind. The proteolytic enzyme bromelain (EC 3.4.22.4) is precipitated with alcohol at low temperature in a fed-batch jacketed tank. Temperature control is crucial to avoid irreversible protein denaturation. Fuzzy or neural controllers offer a way of implementing solutions that cover dynamic and nonlinear processes. The design methodology and a comparative study on the performance of fuzzy-PI, neurofuzzy, and neural network intelligent controllers are presented. To tune the fuzzy PI Mamdani controller, various universes of discourse, rule bases, and membership function support sets were tested. A neurofuzzy inference system (ANFIS), based on Takagi-Sugeno rules, and a model predictive controller, based on neural modeling, were developed and tested as well. Using a Fieldbus network architecture, a coolant variable speed pump was driven by the controllers. The experimental results show the effectiveness of fuzzy controllers in comparison to the neural predictive control. The fuzzy PI controller exhibited a reduced error parameter (ITAE), lower power consumption, and better recovery of enzyme activity. PMID:21234106

Culture of science: strange history of the methodological thinking in psychology.

PubMed

Toomela, Aaro

2007-03-01

In pre-World-War-II psychology, two directions in methodological thought-the German-Austrian and North American ways-could be differentiated. After the war, the German-Austrian methodological orientation has been largely abandoned. Compared to the pre-WWII German-Austrian psychology, modern mainstream psychology is more concerned with accumulation of facts than with general theory. Furthermore, the focus on qualitative data-in addition to quantitative data-is rarely visible. Only external-physical or statistical-rather than psychological controls are taken into account in empirical studies. Fragments--rather than wholes-and relationships are studied, and single cases that contradict group data are not analyzed. Instead of complex psychological types simple trait differences are studied, and prediction is not followed by thorough analysis of the whole situation. Last (but not least), data are not systematically related to complex theory. These limits have hindered the growth of knowledge in the behavioral sciences. A new return to an updated version of the German-Austrian methodological trajectory is suggested.

E-therapy for mental health problems: a systematic review.

PubMed

Postel, Marloes G; de Haan, Hein A; De Jong, Cor A J

2008-09-01

The widespread availability of the Internet offers opportunities for improving access to therapy for people with mental health problems. There is a seemingly infinite supply of Internet-based interventions available on the World Wide Web. The aim of the present study is to systematically assess the methodological quality of randomized controlled trials (RCTs) concerning e-therapy for mental health problems. Two reviewers independently assessed the methodological quality of the RCTs, based on a list of criteria for the methodological quality assessment as recommended by the Cochrane Back Review Group. The search yielded 14 papers that reported RCTs concerning e-therapy for mental-health problems. The methodological quality of studies included in this review was generally low. It is concluded that e-therapy may turn out to be an appropriate therapeutic entity, but the evidence needs to be more convincing. Recommendations are made concerning the method of reporting RCTs and the need to add some content items to an e-therapy study.

Adult day health care evaluation study: methodology and implementation. Adult Day Health Care Evaluation Development Group.

PubMed Central

Hedrick, S C; Rothman, M L; Chapko, M; Inui, T S; Kelly, J R; Ehreth, J

1991-01-01

The Adult Day Health Care Evaluation Study was developed in response to a congressional mandate to study the medical efficacy and cost effectiveness of the Adult Day Health Care (ADHC) effort in the Department of Veterans Affairs (VA). Four sites providing ADHC in VA facilities are participating in an ongoing randomized controlled trial. Three years of developmental work prior to the study addressed methodological issues that were problematic in previous studies. This developmental work resulted in the methodological approaches described here: (1) a patient recruitment process that actively recruits and screens all potential candidates using empirically developed admission criteria based on predictors of nursing home placement in VA; (2) the selection and development of measures of medical efficacy that assess a wide range of patient and caregiver outcomes with sufficient sensitivity to detect small but clinically important changes; and (3) methods for detailed, accurate, and efficient measurement of utilization and costs of health care within and outside VA. These approaches may be helpful to other researchers and may advance the methodological sophistication of long-term care program evaluation. PMID:1991678

Neuropsychological investigations in obsessive-compulsive disorder: A systematic review of methodological challenges.

PubMed

Abramovitch, Amitai; Mittelman, Andrew; Tankersley, Amelia P; Abramowitz, Jonathan S; Schweiger, Avraham

2015-07-30

The inconsistent nature of the neuropsychology literature pertaining to obsessive-compulsive disorder (OCD) has long been recognized. However, individual studies, systematic reviews, and recent meta-analytic reviews were unsuccessful in establishing a consensus regarding a disorder-specific neuropsychological profile. In an attempt to identify methodological factors that may contribute to the inconsistency that is characteristic of this body of research, a systematic review of methodological factors in studies comparing OCD patients and non-psychiatric controls on neuropsychological tests was conducted. This review covered 115 studies that included nearly 3500 patients. Results revealed a range of methodological weaknesses. Some of these weaknesses have been previously noted in the broader neuropsychological literature, while some are more specific to psychiatric disorders, and to OCD. These methodological shortcomings have the potential to hinder the identification of a specific neuropsychological profile associated with OCD as well as to obscure the association between neurocognitive dysfunctions and contemporary neurobiological models. Rectifying these weaknesses may facilitate replicability, and promote our ability to extract cogent, meaningful, and more unified inferences regarding the neuropsychology of OCD. To that end, we present a set of methodological recommendations to facilitate future neuropsychology research in psychiatric disorders in general, and in OCD in particular. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Installation Restoration Program Records Search for Kingsley Field, Oregon.

DTIC Science & Technology

1982-06-01

Hazardous Assesment Rating Methodology (HARM), is now used for all Air Force IRP studies. To maintain consistency, AFESC had their on-call contractors review...Installation History D. Industrial Facilities E. POL Storage Tanks F. Abandoned Tanks G. Oil/Water Separators :" H. Site Hazard Rating Methodology I. Site...and implementing regulations. The pur- pose of DOD policy is to control the migration of hazardous material contaminants from DOD installations. 3

Nonlinear stability and control study of highly maneuverable high performance aircraft, phase 2

NASA Technical Reports Server (NTRS)

Mohler, R. R.

1992-01-01

Research leading to the development of new nonlinear methodologies for the adaptive control and stability analysis of high angle of attack aircraft such as the F-18 is discussed. The emphasis has been on nonlinear adaptive control, but associated model development, system identification, stability analysis, and simulation were studied in some detail as well. Studies indicated that nonlinear adaptive control can outperform linear adaptive control for rapid maneuvers with large changes in angle of attack. Included here are studies on nonlinear model algorithmic controller design and an analysis of nonlinear system stability using robust stability analysis for linear systems.

Methodological idiosyncracies, frameworks and challenges of non-pharmaceutical and non-technical treatment interventions.

PubMed

Schünemann, Holger J

2013-01-01

In this brief article which summarises a presentation given at the "6. Diskussionsforum zur Nutzenbewertung im Gesundheitswesen" of the German Ministry of Education and Research "Gesundheitsforschungsrat (GFR)" and the Institute for Quality and Efficiency in Healthcare (IQWiG) I will analyse some methodological idiosyncrasies of studies evaluating non-pharmacological non-technical interventions (NPNTI). I will focus on how the methodological framework of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) working group may support design and appraisal of NPNTI. Specific design features that may be of particular value in NPNTI research, such as expertise-based randomised controlled trials, will be briefly described. Finally, based on an example, I will argue that - despite the methodological idiosyncrasies - there is neither a sufficient reason to accept different standards for the assessment of the confidence in the evidence from NPNTI nor for using study designs that are less rigorous compared to "simpler" interventions but that special measures have to be taken to reduce the risk of bias. The example that will be used in this article will primarily come from the field of respiratory rehabilitation, a typical multi-component or complex intervention and by definition a complex NPNTI, which has been evaluated in many randomised controlled trials. (As supplied by publisher). Copyright © 2013. Published by Elsevier GmbH.

76 FR 51056 - Notice of Random Assignment Study To Evaluate the YouthBuild Program; Request for Comment

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-17

... assigned to the control group can re-apply to the YouthBuild program. The Department is soliciting comments... ``utilize appropriate methodology and research designs, including the use of control groups chosen by.... Accordingly, ETA is conducting a multisite control group evaluation to provide rigorous estimates [[Page 51058...

The Role of Well Control Training in Developing Safe Onshore and Offshore Oil Drilling Operations

ERIC Educational Resources Information Center

Abulhassn, Aber

2016-01-01

This research investigates the role of the International Well Control Forum (IWCF) Rotary Drilling Well Control Training Program in developing safe oil drilling operations from the perspective of onshore and offshore drilling crews. The research methodology is a qualitative case study. A total of 40 IWCF candidates were interviewed, with 10 from…

Motor Disorder and Anxious and Depressive Symptomatology: A Monozygotic Co-Twin Control Approach

ERIC Educational Resources Information Center

Pearsall-Jones, Jillian G.; Piek, Jan P.; Rigoli, Daniela; Martin, Neilson C.; Levy, Florence

2011-01-01

The aim of this study was to investigate the relationship between poor motor ability and anxious and depressive symptomatology in child and adolescent monozygotic twins. The co-twin control design was used to explore these mental health issues in MZ twins concordant and discordant for a motor disorder, and controls. This methodology offers the…

Observational Studies: Cohort and Case-Control Studies

PubMed Central

Song, Jae W.; Chung, Kevin C.

2010-01-01

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

A Robust Design Methodology for Optimal Microscale Secondary Flow Control in Compact Inlet Diffusers

NASA Technical Reports Server (NTRS)

Anderson, Bernhard H.; Keller, Dennis J.

2001-01-01

It is the purpose of this study to develop an economical Robust design methodology for microscale secondary flow control in compact inlet diffusers. To illustrate the potential of economical Robust Design methodology, two different mission strategies were considered for the subject inlet, namely Maximum Performance and Maximum HCF Life Expectancy. The Maximum Performance mission maximized total pressure recovery while the Maximum HCF Life Expectancy mission minimized the mean of the first five Fourier harmonic amplitudes, i.e., 'collectively' reduced all the harmonic 1/2 amplitudes of engine face distortion. Each of the mission strategies was subject to a low engine face distortion constraint, i.e., DC60<0.10, which is a level acceptable for commercial engines. For each of these missions strategies, an 'Optimal Robust' (open loop control) and an 'Optimal Adaptive' (closed loop control) installation was designed over a twenty degree angle-of-incidence range. The Optimal Robust installation used economical Robust Design methodology to arrive at a single design which operated over the entire angle-of-incident range (open loop control). The Optimal Adaptive installation optimized all the design parameters at each angle-of-incidence. Thus, the Optimal Adaptive installation would require a closed loop control system to sense a proper signal for each effector and modify that effector device, whether mechanical or fluidic, for optimal inlet performance. In general, the performance differences between the Optimal Adaptive and Optimal Robust installation designs were found to be marginal. This suggests, however, that Optimal Robust open loop installation designs can be very competitive with Optimal Adaptive close loop designs. Secondary flow control in inlets is inherently robust, provided it is optimally designed. Therefore, the new methodology presented in this paper, combined array 'Lower Order' approach to Robust DOE, offers the aerodynamicist a very viable and economical way of exploring the concept of Robust inlet design, where the mission variables are brought directly into the inlet design process and insensitivity or robustness to the mission variables becomes a design objective.

Eutrophication assessment and management methodology of multiple pollution sources of a landscape lake in North China.

PubMed

Chen, Yanxi; Niu, Zhiguang; Zhang, Hongwei

2013-06-01

Landscape lakes in the city suffer high eutrophication risk because of their special characters and functions in the water circulation system. Using a landscape lake HMLA located in Tianjin City, North China, with a mixture of point source (PS) pollution and non-point source (NPS) pollution, we explored the methodology of Fluent and AQUATOX to simulate and predict the state of HMLA, and trophic index was used to assess the eutrophication state. Then, we use water compensation optimization and three scenarios to determine the optimal management methodology. Three scenarios include ecological restoration scenario, best management practices (BMPs) scenario, and a scenario combining both. Our results suggest that the maintenance of a healthy ecosystem with ecoremediation is necessary and the BMPs have a far-reaching effect on water reusing and NPS pollution control. This study has implications for eutrophication control and management under development for urbanization in China.

Definitions and methods of measuring and reporting on injurious falls in randomised controlled fall prevention trials: a systematic review

PubMed Central

2012-01-01

Background The standardisation of the assessment methodology and case definition represents a major precondition for the comparison of study results and the conduction of meta-analyses. International guidelines provide recommendations for the standardisation of falls methodology; however, injurious falls have not been targeted. The aim of the present article was to review systematically the range of case definitions and methods used to measure and report on injurious falls in randomised controlled trials (RCTs) on fall prevention. Methods An electronic literature search of selected comprehensive databases was performed to identify injurious falls definitions in published trials. Inclusion criteria were: RCTs on falls prevention published in English, study population ≥ 65 years, definition of injurious falls as a study endpoint by using the terms "injuries" and "falls". Results The search yielded 2089 articles, 2048 were excluded according to defined inclusion criteria. Forty-one articles were included. The systematic analysis of the methodology applied in RCTs disclosed substantial variations in the definition and methods used to measure and document injurious falls. The limited standardisation hampered comparability of study results. Our results also highlight that studies which used a similar, standardised definition of injurious falls showed comparable outcomes. Conclusions No standard for defining, measuring, and documenting injurious falls could be identified among published RCTs. A standardised injurious falls definition enhances the comparability of study results as demonstrated by a subgroup of RCTs used a similar definition. Recommendations for standardising the methodology are given in the present review. PMID:22510239

Hypnosis for procedure-related pain and distress in pediatric cancer patients: a systematic review of effectiveness and methodology related to hypnosis interventions.

PubMed

Richardson, Janet; Smith, Joanna E; McCall, Gillian; Pilkington, Karen

2006-01-01

The aim of this study was to systematically review and critically appraise the evidence on the effectiveness of hypnosis for procedure-related pain and distress in pediatric cancer patients. A comprehensive search of major biomedical and specialist complementary and alternative medicine databases was conducted. Citations were included from the databases' inception to March 2005. Efforts were made to identify unpublished and ongoing research. Controlled trials were appraised using predefined criteria. Clinical commentaries were obtained for each study. Seven randomized controlled clinical trials and one controlled clinical trial were found. Studies report positive results, including statistically significant reductions in pain and anxiety/distress, but a number of methodological limitations were identified. Systematic searching and appraisal has demonstrated that hypnosis has potential as a clinically valuable intervention for procedure-related pain and distress in pediatric cancer patients. Further research into the effectiveness and acceptability of hypnosis for pediatric cancer patients is recommended.

Children's concepts of physical illness: a review and critique of the cognitive-developmental literature.

PubMed

Burbach, D J; Peterson, L

1986-01-01

Cognitive-developmental studies relevant to children's concepts of physical illness are reviewed and critiqued. Although numerous methodological weaknesses make firm conclusions difficult, most data appear to suggest that children's concepts of illness do evolve in a systematic and predictable sequence consistent with Piaget's theory of cognitive development. Methodological weaknesses identified include poor description of samples, assessment instruments, and procedures; lack of control over potential observer bias, expectancy effects, and other confounding variables; and minimal attention to reliability and validity issues. Increased methodological rigor and a further explication of the specific and unique ways in which children's concepts of illness develop over the course of cognitive development could substantially increase the value of these studies for professionals in pediatric health care settings.

A Methodological Analysis of Randomized Clinical Trials of Computer-Assisted Therapies for Psychiatric Disorders: Toward Improved Standards for an Emerging Field

PubMed Central

Kiluk, Brian D.; Sugarman, Dawn E.; Nich, Charla; Gibbons, Carly J.; Martino, Steve; Rounsaville, Bruce J.; Carroll, Kathleen M.

2013-01-01

Objective Computer-assisted therapies offer a novel, cost-effective strategy for providing evidence-based therapies to a broad range of individuals with psychiatric disorders. However, the extent to which the growing body of randomized trials evaluating computer-assisted therapies meets current standards of methodological rigor for evidence-based interventions is not clear. Method A methodological analysis of randomized clinical trials of computer-assisted therapies for adult psychiatric disorders, published between January 1990 and January 2010, was conducted. Seventy-five studies that examined computer-assisted therapies for a range of axis I disorders were evaluated using a 14-item methodological quality index. Results Results indicated marked heterogeneity in study quality. No study met all 14 basic quality standards, and three met 13 criteria. Consistent weaknesses were noted in evaluation of treatment exposure and adherence, rates of follow-up assessment, and conformity to intention-to-treat principles. Studies utilizing weaker comparison conditions (e.g., wait-list controls) had poorer methodological quality scores and were more likely to report effects favoring the computer-assisted condition. Conclusions While several well-conducted studies have indicated promising results for computer-assisted therapies, this emerging field has not yet achieved a level of methodological quality equivalent to those required for other evidence-based behavioral therapies or pharmacotherapies. Adoption of more consistent standards for methodological quality in this field, with greater attention to potential adverse events, is needed before computer-assisted therapies are widely disseminated or marketed as evidence based. PMID:21536689

Adaptation of EVIAVE methodology for monitoring and follow-up when evaluating the environmental impact of landfills

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

Arrieta, Gabriela, E-mail: tonina1903@hotmail.com; Requena, Ignacio, E-mail: requena@decsai.ugr.es; Toro, Javier, E-mail: jjtoroca@unal.edu.co

Treatment and final disposal of Municipal Solid Waste can have a significant role in the generation of negative environmental impacts. As a prevention strategy, such activities are subjected to the process of Environmental Impact Assessment (EIA). Still, the follow-up of Environmental Management Plans or mitigation measures is limited, for one due to a lack of methodological approaches. In searching for possibilities, the University of Granada (Spain) developed a diagnostic methodology named EVIAVE, which allows one to quantify, by means of indexes, the environmental impact of landfills in view of their location and the conditions of exploitation. EVIAVE is applicable withinmore » the legal framework of the European Union and can be adapted to the environmental and legal conditions of other countries. This study entails its adaptation in Colombia, for the follow-up and control of the EIA process for landfills. Modifications involved inclusion of the environmental elements flora and fauna, and the evaluation of the environmental descriptors in agreement with the concept of vulnerability. The application of the modified EVIAVE in Colombian landfills allowed us to identify the elements affected by the operating conditions and maintenance. It may be concluded that this methodology is viable and effective for the follow-up and environmental control of EIA processes for landfills, and to analyze the associated risks, as it takes into account related environmental threats and vulnerabilities. - Highlights: • A modified methodology is used to monitor and follow-up environmental impacts in landfills. • The improved methodology includes the Vulnerability of Flora and Fauna to evaluate environmental impact of landfills. • The methodology serves to identify and evaluate the sources of risk generated in the construction and siting of landfills. • Environmental vulnerability indicators improve effectiveness of the control and follow-up phases of landfill management. • The follow-up of environmental management plans may help diminish the implementation gap in Environmental Impact Assessment.« less

Integrated Psychosocial and Opioid-Antagonist Treatment for Alcohol Dependence: A Systematic Review of Controlled Evaluations

ERIC Educational Resources Information Center

Vaughn, Michael G.; Howard, Matthew O.

2004-01-01

Methodological characteristics and outcomes of 14 controlled clinical investigations of integrated psychosocial and opioid-antagonist alcohol dependence treatment were evaluated. The 14 studies were identified through computerized bibliographic and manual literature searches. Clients receiving integrated psychosocial and opioid-antagonist…

Is there an "abortion trauma syndrome"? Critiquing the evidence.

PubMed

Robinson, Gail Erlick; Stotland, Nada L; Russo, Nancy Felipe; Lang, Joan A; Occhiogrosso, Mallay

2009-01-01

The objective of this review is to identify and illustrate methodological issues in studies used to support claims that induced abortion results in an "abortion trauma syndrome" or a psychiatric disorder. After identifying key methodological issues to consider when evaluating such research, we illustrate these issues by critically examining recent empirical studies that are widely cited in legislative and judicial testimony in support of the existence of adverse psychiatric sequelae of induced abortion. Recent studies that have been used to assert a causal connection between abortion and subsequent mental disorders are marked by methodological problems that include, but not limited to: poor sample and comparison group selection; inadequate conceptualization and control of relevant variables; poor quality and lack of clinical significance of outcome measures; inappropriateness of statistical analyses; and errors of interpretation, including misattribution of causal effects. By way of contrast, we review some recent major studies that avoid these methodological errors. The most consistent predictor of mental disorders after abortion remains preexisting disorders, which, in turn, are strongly associated with exposure to sexual abuse and intimate violence. Educating researchers, clinicians, and policymakers how to appropriately assess the methodological quality of research about abortion outcomes is crucial. Further, methodologically sound research is needed to evaluate not only psychological outcomes of abortion, but also the impact of existing legislation and the effects of social attitudes and behaviors on women who have abortions.

A Life-Cycle Cost Estimating Methodology for NASA-Developed Air Traffic Control Decision Support Tools

NASA Technical Reports Server (NTRS)

Wang, Jianzhong Jay; Datta, Koushik; Landis, Michael R. (Technical Monitor)

2002-01-01

This paper describes the development of a life-cycle cost (LCC) estimating methodology for air traffic control Decision Support Tools (DSTs) under development by the National Aeronautics and Space Administration (NASA), using a combination of parametric, analogy, and expert opinion methods. There is no one standard methodology and technique that is used by NASA or by the Federal Aviation Administration (FAA) for LCC estimation of prospective Decision Support Tools. Some of the frequently used methodologies include bottom-up, analogy, top-down, parametric, expert judgement, and Parkinson's Law. The developed LCC estimating methodology can be visualized as a three-dimensional matrix where the three axes represent coverage, estimation, and timing. This paper focuses on the three characteristics of this methodology that correspond to the three axes.

Changes in clinical trials methodology over time: a systematic review of six decades of research in psychopharmacology.

PubMed

Brunoni, André R; Tadini, Laura; Fregni, Felipe

2010-03-03

There have been many changes in clinical trials methodology since the introduction of lithium and the beginning of the modern era of psychopharmacology in 1949. The nature and importance of these changes have not been fully addressed to date. As methodological flaws in trials can lead to false-negative or false-positive results, the objective of our study was to evaluate the impact of methodological changes in psychopharmacology clinical research over the past 60 years. We performed a systematic review from 1949 to 2009 on MEDLINE and Web of Science electronic databases, and a hand search of high impact journals on studies of seven major drugs (chlorpromazine, clozapine, risperidone, lithium, fluoxetine and lamotrigine). All controlled studies published 100 months after the first trial were included. Ninety-one studies met our inclusion criteria. We analyzed the major changes in abstract reporting, study design, participants' assessment and enrollment, methodology and statistical analysis. Our results showed that the methodology of psychiatric clinical trials changed substantially, with quality gains in abstract reporting, results reporting, and statistical methodology. Recent trials use more informed consent, periods of washout, intention-to-treat approach and parametric tests. Placebo use remains high and unchanged over time. Clinical trial quality of psychopharmacological studies has changed significantly in most of the aspects we analyzed. There was significant improvement in quality reporting and internal validity. These changes have increased study efficiency; however, there is room for improvement in some aspects such as rating scales, diagnostic criteria and better trial reporting. Therefore, despite the advancements observed, there are still several areas that can be improved in psychopharmacology clinical trials.

Advanced piloted aircraft flight control system design methodology. Volume 2: The FCX flight control design expert system

NASA Technical Reports Server (NTRS)

Myers, Thomas T.; Mcruer, Duane T.

1988-01-01

The development of a comprehensive and electric methodology for conceptual and preliminary design of flight control systems is presented and illustrated. The methodology is focused on the design states starting with the layout of system requirements and ending when some viable competing system architectures (feedback control structures) are defined. The approach is centered on the human pilot and the aircraft as both the sources of, and the keys to the solution of, many flight control problems. The methodology relies heavily on computational procedures which are highly interactive with the design engineer. To maximize effectiveness, these techniques, as selected and modified to be used together in the methodology, form a cadre of computational tools specifically tailored for integrated flight control system preliminary design purposes. The FCX expert system as presently developed is only a limited prototype capable of supporting basic lateral-directional FCS design activities related to the design example used. FCX presently supports design of only one FCS architecture (yaw damper plus roll damper) and the rules are largely focused on Class IV (highly maneuverable) aircraft. Despite this limited scope, the major elements which appear necessary for application of knowledge-based software concepts to flight control design were assembled and thus FCX represents a prototype which can be tested, critiqued and evolved in an ongoing process of development.

Proactive telephone counseling for smoking cessation: meta-analyses by recruitment channel and methodological quality.

PubMed

Tzelepis, Flora; Paul, Christine L; Walsh, Raoul A; McElduff, Patrick; Knight, Jenny

2011-06-22

Systematic reviews demonstrated that proactive telephone counseling increases smoking cessation rates. However, these reviews did not differentiate studies by recruitment channel, did not adequately assess methodological quality, and combined different measures of abstinence. Twenty-four randomized controlled trials published before December 31, 2008, included seven of active recruitment, 16 of passive recruitment, and one of mixed recruitment. We rated methodological quality on selection bias, study design, confounders, blinding, data collection methods, withdrawals, and dropouts, according to the Quality Assessment Tool for Quantitative Studies. We conducted random effects meta-analysis to pool the results according to abstinence type and follow-up time for studies overall and segregated by recruitment channel, and methodological quality. The level of statistical heterogeneity was quantified by I(2). All statistical tests were two-sided. Methodological quality ratings indicated two strong, 10 moderate, and 12 weak studies. Overall, compared with self-help materials or no intervention control groups, proactive telephone counseling had a statistically significantly greater effect on point prevalence abstinence (nonsmoking at follow-up or abstinent for at least 24 hours, 7 days before follow-up) at 6-9 months (relative risk [RR] = 1.26, 95% confidence interval [CI] = 1.11 to 1.43, P < .001, I(2) = 21.4%) but not at 12-15 months after recruitment. This pattern also emerged when studies were segregated by recruitment channel (active, passive) or methodological quality (strong/moderate, weak). Overall, the positive effect on prolonged/continuous abstinence (abstinent for 3 months or longer before follow-up) was also statistically significantly greater at 6-9 months (RR = 1.58, CI = 1.26 to 1.98, P < .001, I(2) = 49.1%) and 12-18 months after recruitment (RR = 1.40, CI = 1.23 to 1.60, P < .001, I(2) = 18.5%). With the exception of point prevalence abstinence in the long term, these data support previous results showing that proactive telephone counseling has a positive impact on smoking cessation. Proactive telephone counseling increased prolonged/continuous abstinence long term for both actively and passively recruited smokers.

On the hunt for the gene of perspective taking: pitfalls in methodology.

PubMed

Miklósi, Adám; Topál, József

2011-12-01

In this commentary, we evaluate the methodology of Udell, Dorey, and Wynne's (Learning & Behavior, in press) experiment in controlling for environmental factors and argue that their conclusion is not supported. In particular, we emphasise that comparative studies on dogs and wolves need to ensure that both species enjoyed the same rearing history, are comparable in age, and have the same experience with the testing conditions. We also argue that the utilisation of shelter dogs does not control for genetic effects on social behaviour. Finally, we propose a synergetic model to account for both genetic and environmental effects on interspecific social behaviour in dogs and wolves.

Investigating on the Methodology Effect When Evaluating Lucid Dream

PubMed Central

Ribeiro, Nicolas; Gounden, Yannick; Quaglino, Véronique

2016-01-01

Lucid dreaming (LD) is a state of consciousness in which the dreamer is aware that he or she is dreaming and can possibly control the content of his or her dream. To investigate the LD prevalence among different samples, researchers have used different types of methodologies. With regard to retrospective self-report questionnaire, two ways of proceeding seem to emerge. In one case, a definition of LD is given to participants (“During LD, one is–while dreaming–aware of the fact that one is dreaming. It is possible to deliberately wake up, to control the dream action, or to observe passively the course of the dream with this awareness”), while in the other instances, participants are presented separate questions targeting specific LD indicators (dream awareness and dream control). In the present study, we measured LD frequency in a sample of French student in order to investigate for possible disparities in LD frequency depending on the type of questionnaire as outlined above. Moreover, we also study links between the prevalence of LD as assessed, respectively, by each questionnaire with various factors such as Vividness of Mental Imagery and Parasomnia. Results revealed no significant difference between LD frequencies across questionnaires. For the questionnaire with definition (DefQuest), 81.05% of participants reported experience of LD once or more. Concerning the questionnaire based on LD indicators (AwarContQuest), 73.38% of participants reported having experienced LD once or more. However, with regard to the correlations analysis, links between LD prevalence and factors such as Vividness of Mental Imagery and Parasomnia, varied across questionnaires. This result is an argument suggesting that researchers should be careful when investigating links between LD and other factors. The type of methodology may influence findings on LD research. Further studies are needed to investigate on the methodology effect in LD research namely on the respective weight of awareness and control. PMID:27625622

Methodological reporting of randomized controlled trials in major hepato-gastroenterology journals in 2008 and 1998: a comparative study

PubMed Central

2011-01-01

Background It was still unclear whether the methodological reporting quality of randomized controlled trials (RCTs) in major hepato-gastroenterology journals improved after the Consolidated Standards of Reporting Trials (CONSORT) Statement was revised in 2001. Methods RCTs in five major hepato-gastroenterology journals published in 1998 or 2008 were retrieved from MEDLINE using a high sensitivity search method and their reporting quality of methodological details were evaluated based on the CONSORT Statement and Cochrane Handbook for Systematic Reviews of interventions. Changes of the methodological reporting quality between 2008 and 1998 were calculated by risk ratios with 95% confidence intervals. Results A total of 107 RCTs published in 2008 and 99 RCTs published in 1998 were found. Compared to those in 1998, the proportion of RCTs that reported sequence generation (RR, 5.70; 95%CI 3.11-10.42), allocation concealment (RR, 4.08; 95%CI 2.25-7.39), sample size calculation (RR, 3.83; 95%CI 2.10-6.98), incomplete outecome data addressed (RR, 1.81; 95%CI, 1.03-3.17), intention-to-treat analyses (RR, 3.04; 95%CI 1.72-5.39) increased in 2008. Blinding and intent-to-treat analysis were reported better in multi-center trials than in single-center trials. The reporting of allocation concealment and blinding were better in industry-sponsored trials than in public-funded trials. Compared with historical studies, the methodological reporting quality improved with time. Conclusion Although the reporting of several important methodological aspects improved in 2008 compared with those published in 1998, which may indicate the researchers had increased awareness of and compliance with the revised CONSORT statement, some items were still reported badly. There is much room for future improvement. PMID:21801429

Research and development activities in unified control-structure modeling and design

NASA Technical Reports Server (NTRS)

Nayak, A. P.

1985-01-01

Results of work to develop a unified control/structures modeling and design capability for large space structures modeling are presented. Recent analytical results are presented to demonstrate the significant interdependence between structural and control properties. A new design methodology is suggested in which the structure, material properties, dynamic model and control design are all optimized simultaneously. Parallel research done by other researchers is reviewed. The development of a methodology for global design optimization is recommended as a long-term goal. It is suggested that this methodology should be incorporated into computer aided engineering programs, which eventually will be supplemented by an expert system to aid design optimization.

Systematic Review of Knowledge Translation Strategies to Promote Research Uptake in Child Health Settings.

PubMed

Albrecht, Lauren; Archibald, Mandy; Snelgrove-Clarke, Erna; Scott, Shannon D

2016-01-01

Strategies to assist evidence-based decision-making for healthcare professionals are crucial to ensure high quality patient care and outcomes. The goal of this systematic review was to identify and synthesize the evidence on knowledge translation interventions aimed at putting explicit research evidence into child health practice. A comprehensive search of thirteen electronic databases was conducted, restricted by date (1985-2011) and language (English). Articles were included if: 1) studies were randomized controlled trials (RCT), controlled clinical trials (CCT), or controlled before-and-after (CBA) studies; 2) target population was child health professionals; 3) interventions implemented research in child health practice; and 4) outcomes were measured at the professional/process, patient, or economic level. Two reviewers independently extracted data and assessed methodological quality. Study data were aggregated and analyzed using evidence tables. Twenty-one studies (13 RCT, 2 CCT, 6 CBA) were included. The studies employed single (n=9) and multiple interventions (n=12). The methodological quality of the included studies was largely moderate (n=8) or weak (n=11). Of the studies with moderate to strong methodological quality ratings, three demonstrated consistent, positive effect(s) on the primary outcome(s); effective knowledge translation interventions were two single, non-educational interventions and one multiple, educational intervention. This multidisciplinary systematic review in child health setting identified effective knowledge translation strategies assessed by the most rigorous research designs. Given the overall poor quality of the research literature, specific recommendations were made to improve knowledge translation efforts in child health. Copyright © 2016 Elsevier Inc. All rights reserved.

A methodology for designing robust multivariable nonlinear control systems. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Grunberg, D. B.

1986-01-01

A new methodology is described for the design of nonlinear dynamic controllers for nonlinear multivariable systems providing guarantees of closed-loop stability, performance, and robustness. The methodology is an extension of the Linear-Quadratic-Gaussian with Loop-Transfer-Recovery (LQG/LTR) methodology for linear systems, thus hinging upon the idea of constructing an approximate inverse operator for the plant. A major feature of the methodology is a unification of both the state-space and input-output formulations. In addition, new results on stability theory, nonlinear state estimation, and optimal nonlinear regulator theory are presented, including the guaranteed global properties of the extended Kalman filter and optimal nonlinear regulators.

Teaching Medical Ethics in Graduate and Undergraduate Medical Education: A Systematic Review of Effectiveness.

PubMed

de la Garza, Santiago; Phuoc, Vania; Throneberry, Steven; Blumenthal-Barby, Jennifer; McCullough, Laurence; Coverdale, John

2017-08-01

One objective was to identify and review studies on teaching medical ethics to psychiatry residents. In order to gain insights from other disciplines that have published research in this area, a second objective was to identify and review studies on teaching medical ethics to residents across all other specialties of training and on teaching medical students. PubMed, EMBASE, and PsycINFO were searched for controlled trials on teaching medical ethics with quantitative outcomes. Search terms included ethics, bioethics, medical ethics, medical students, residents/registrars, teaching, education, outcomes, and controlled trials. Nine studies were found that met inclusion criteria, including five randomized controlled trails and four controlled non-randomized trials. Subjects included medical students (5 studies), surgical residents (2 studies), internal medicine house officers (1 study), and family medicine preceptors and their medical students (1 study). Teaching methods, course content, and outcome measures varied considerably across studies. Common methodological issues included a lack of concealment of allocation, a lack of blinding, and generally low numbers of subjects as learners. One randomized controlled trial which taught surgical residents using a standardized patient was judged to be especially methodologically rigorous. None of the trials incorporated psychiatry residents. Ethics educators should undertake additional rigorously controlled trials in order to secure a strong evidence base for the design of medical ethics curricula. Psychiatry ethics educators can also benefit from the findings of trials in other disciplines and in undergraduate medical education.

Non-contact versus contact-based sensing methodologies for in-home upper arm robotic rehabilitation.

PubMed

Howard, Ayanna; Brooks, Douglas; Brown, Edward; Gebregiorgis, Adey; Chen, Yu-Ping

2013-06-01

In recent years, robot-assisted rehabilitation has gained momentum as a viable means for improving outcomes for therapeutic interventions. Such therapy experiences allow controlled and repeatable trials and quantitative evaluation of mobility metrics. Typically though these robotic devices have been focused on rehabilitation within a clinical setting. In these traditional robot-assisted rehabilitation studies, participants are required to perform goal-directed movements with the robot during a therapy session. This requires physical contact between the participant and the robot to enable precise control of the task, as well as a means to collect relevant performance data. On the other hand, non-contact means of robot interaction can provide a safe methodology for extracting the control data needed for in-home rehabilitation. As such, in this paper we discuss a contact and non-contact based method for upper-arm rehabilitation exercises that enables quantification of upper-arm movements. We evaluate our methodology on upper-arm abduction/adduction movements and discuss the advantages and limitations of each approach as applied to an in-home rehabilitation scenario.

ERPs and Psychopathology. I. Behavioral process issues.

PubMed

Roth, W T; Tecce, J J; Pfefferbaum, A; Rosenbloom, M; Callaway, E

1984-01-01

The clinical study of ERPs has an inherent defect--a self-selection of clinical populations that hampers equating of clinically defined groups on factors extraneous to the independent variables. Such ex post facto studies increase the likelihood of confounding variables in the interpretation of findings. Hence, the development of lawful relationships between clinical variables and ERPs is impeded and the fulfillment of description, explanation, prediction, and control in brain science is thwarted. Proper methodologies and theory development can increase the likelihood of establishing these lawful relationships. One methodology of potential value in the clinical application of ERPs, particularly in studies of aging, is that of divided attention. Two promising theoretical developments in the understanding of brain functioning and aging are the distraction-arousal hypothesis and the controlled-automatic attention model. The evaluation of ERPs in the study of brain-behavior relations in clinical populations might be facilitated by the differentiation of concurrent, predictive, content, and construct validities.

Advanced and Hybrid Powertrains

Science.gov Websites

and analysis, and to create methodologies for evaluating the true potential of proposed advanced architectures, and optimal control strategies. Finally, experimental studies are being conducted to support

Enhanced High Performance Power Compensation Methodology by IPFC Using PIGBT-IDVR

PubMed Central

Arumugom, Subramanian; Rajaram, Marimuthu

2015-01-01

Currently, power systems are involuntarily controlled without high speed control and are frequently initiated, therefore resulting in a slow process when compared with static electronic devices. Among various power interruptions in power supply systems, voltage dips play a central role in causing disruption. The dynamic voltage restorer (DVR) is a process based on voltage control that compensates for line transients in the distributed system. To overcome these issues and to achieve a higher speed, a new methodology called the Parallel IGBT-Based Interline Dynamic Voltage Restorer (PIGBT-IDVR) method has been proposed, which mainly spotlights the dynamic processing of energy reloads in common dc-linked energy storage with less adaptive transition. The interline power flow controller (IPFC) scheme has been employed to manage the power transmission between the lines and the restorer method for controlling the reactive power in the individual lines. By employing the proposed methodology, the failure of a distributed system has been avoided and provides better performance than the existing methodologies. PMID:26613101

Life-Cycle Cost/Benefit Assessment of Expedite Departure Path (EDP)

NASA Technical Reports Server (NTRS)

Wang, Jianzhong Jay; Chang, Paul; Datta, Koushik

2005-01-01

This report presents a life-cycle cost/benefit assessment (LCCBA) of Expedite Departure Path (EDP), an air traffic control Decision Support Tool (DST) currently under development at NASA. This assessment is an update of a previous study performed by bd Systems, Inc. (bd) during FY01, with the following revisions: The life-cycle cost assessment methodology developed by bd for the previous study was refined and calibrated using Free Flight Phase 1 (FFP1) cost information for Traffic Management Advisor (TMA, or TMA-SC in the FAA's terminology). Adjustments were also made to the site selection and deployment scheduling methodology to include airspace complexity as a factor. This technique was also applied to the benefit extrapolation methodology to better estimate potential benefits for other years, and at other sites. This study employed a new benefit estimating methodology because bd s previous single year potential benefit assessment of EDP used unrealistic assumptions that resulted in optimistic estimates. This methodology uses an air traffic simulation approach to reasonably predict the impacts from the implementation of EDP. The results of the costs and benefits analyses were then integrated into a life-cycle cost/benefit assessment.

Care delivery and self-management strategies for children with epilepsy.

PubMed

Fleeman, Nigel; Bradley, Peter M

2018-03-01

In response to criticism that epilepsy care for children has little impact, healthcare professionals and administrators have developed various service models and strategies to address perceived inadequacies. To assess the effects of any specialised or dedicated intervention for epilepsy versus usual care in children with epilepsy and in their families. We searched the Cochrane Epilepsy Group Specialized Register (27 September 2016), the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 9) in the Cochrane Library, MEDLINE (1946 to 27 September 2016), Embase (1974 to 27 September 2016), PsycINFO (1887 to 27 September 2016) and CINAHL Plus (1937 to 27 September 2016). In addition, we also searched clinical trials registries for ongoing or recently completed trials, contacted experts in the field to seek information on unpublished and ongoing studies, checked the websites of epilepsy organisations and checked the reference lists of included studies. We included randomised controlled trials (RCTs), cohort studies or other prospective studies with a (matched or unmatched) control group (controlled before-and-after studies), or time series studies. We used standard methodological procedures expected by Cochrane. Our review included six interventions reported through seven studies (of which five studies were designed as RCTs). They reported on different education and counselling programmes for children and parents; teenagers and parents; or children, adolescents and their parents. Each programme showed some benefits for the well-being of children with epilepsy, but all had methodological flaws (e.g. in one of the studies designed as an RCT, randomisation failed), no single programme was independently evaluated with different study samples and no interventions were sufficiently homogeneous enough to be included in a meta-analysis,. While each of the programmes in this review showed some benefit to children with epilepsy, their impacts were extremely variable. No programme showed benefits across the full range of outcomes, and all studies had major methodological problems. At present there is insufficient evidence in favour of any single programme.

Title: Studies on drug switchability showed heterogeneity in methodological approaches: a scoping review.

PubMed

Belleudi, Valeria; Trotta, Francesco; Vecchi, Simona; Amato, Laura; Addis, Antonio; Davoli, Marina

2018-05-16

Several drugs share the same therapeutic indication, including those undergoing patent expiration. Concerns on the interchangeability are frequent in clinical practice, challenging the evaluation of switchability through observational research. To conduct a scoping review of observational studies on drug switchability to identify methodological strategies adopted to deal with bias and confounding. We searched PubMed, EMBASE, and Web of Science (updated 1/31/2017) to identify studies evaluating switchability in terms of effectiveness/safety outcomes or compliance. Three reviewers independently screened studies extracting all characteristics. Strategies to address confounding, particularly, previous drug use and switching reasons were considered. All findings were summarized in descriptive analyses. Thirty-two studies, published in the last 10 years, met the inclusion criteria. Epilepsy, cardiovascular and rheumatology were the most frequently represented clinical areas. 75% of the studies reported data on effectiveness/safety outcomes. The most frequent study design was cohort (65.6%) followed by case-control (21.9%) and self-controlled (12.5%). Case-control and case-crossover studies showed homogeneous methodological strategies to deal with bias and confounding. Among cohort studies, the confounding associated with previous drug use was addressed introducing variables in multivariate model (47.3%) or selecting only adherent patients (14.3%). Around 30% of cohort studies did not report reasons for switching. In the remaining 70%, clinical parameters or previous occurrence of outcomes were measured to identify switching connected with lack of effectiveness or adverse events. This study represents a starting point for researchers and administrators who are approaching the investigation and assessment of issues related to interchangeability of drugs. Copyright © 2018. Published by Elsevier Inc.

A Systematic Review of Experimental and Clinical Acupuncture in Chemotherapy-Induced Peripheral Neuropathy

PubMed Central

Franconi, Giovanna; Schröder, Sven; Marchetti, Paolo; Robinson, Nicola

2013-01-01

Chemotherapy-induced peripheral neuropathy (CIPN) is a common side effect that can be very disabling and can limit or delay the dose of chemotherapy that can be administered. Acupuncture may be effective for treating peripheral neuropathy. The aim of this study was to review the available literature on the use of acupuncture for CIPN. The systematic literature search was performed using MEDLINE, Google Scholar, Cochrane Database, CINHAL, and ISI Proceedings. Hand searching was conducted, and consensus was reached on all extracted data. Only papers in the English language were included, irrespective of study design. From 3989 retrieved papers, 8 relevant papers were identified. One was an experimental study which showed that electroacupuncture suppressed CIPN pain in rats. In addition, there were 7 very heterogeneous clinical studies, 1 controlled randomised study using auricular acupuncture, 2 randomized controlled studies using somatic acupuncture, and 3 case series/case reports which suggested a positive effect of acupuncture in CIPN. Conclusions. Only one controlled randomised study demonstrated that acupuncture may be beneficial for CIPN. All the clinical studies reviewed had important methodological limitations. Further studies with robust methodology are needed to demonstrate the role of acupuncture for treating CIPN resulting from cancer treatment. PMID:23983788

Methodological Issues in Controlled Studies on Effects of Prenatal Exposure to Drug Abuse. Research Monograph 114.

ERIC Educational Resources Information Center

Kilbey, M. Marlyne, Ed.; Asghar, Khursheed, Ed.

This monograph presents the proceedings of the first National Institute on Drug Abuse technical review related to the conduct of controlled studies on prenatal exposure to drugs of abuse. Papers in the monograph are categorized by session. The first session (two papers) focused on the detection and quantification of prenatal drug exposure in…

H-infinity based integrated flight-propulsion control design for a STOVL aircraft in transition flight

NASA Technical Reports Server (NTRS)

Garg, Sanjay; Mattern, Duane L.; Bright, Michelle M.; Ouzts, Peter J.

1990-01-01

Results are presented from an application of H-infinity control design methodology to a centralized integrated flight/propulsion control (IFPC) system design for a supersonic Short Take-Off and Vertical Landing (STOVL) fighter aircraft in transition flight. The overall design methodology consists of a centralized IFPC controller design with controller partitioning. Only the feedback controller design portion of the methodology is addressed. Design and evaluation vehicle models are summarized, and insight is provided into formulating the H-infinity control problem such that it reflects the IFPC design objectives. The H-infinity controller is shown to provide decoupled command tracking for the design model. The controller order could be significantly reduced by modal residualization of the fast controller modes without any deterioration in performance. A discussion is presented of the areas in which the controller performance needs to be improved, and ways in which these improvements can be achieved within the framework of an H-infinity based linear control design.

Administrative Leadership as Projection, Social Control, and Action.

ERIC Educational Resources Information Center

Reed, Donald B.

Over the past 50 years, theoretical and methodological problems have plagued the study of leadership. This paper, proposing an alternative theory, argues that leadership has three fundamental components: projection and social control, which are linked by action. Projection is the visualization of a project to be completed. Educational…

Monitoring safety in a phase III real‐world effectiveness trial: use of novel methodology in the Salford Lung Study

PubMed Central

Harvey, Catherine; Brewster, Jill; Bakerly, Nawar Diar; Elkhenini, Hanaa F.; Stanciu, Roxana; Williams, Claire; Brereton, Jacqui; New, John P.; McCrae, John; McCorkindale, Sheila; Leather, David

2016-01-01

Abstract Background The Salford Lung Study (SLS) programme, encompassing two phase III pragmatic randomised controlled trials, was designed to generate evidence on the effectiveness of a once‐daily treatment for asthma and chronic obstructive pulmonary disease in routine primary care using electronic health records. Objective The objective of this study was to describe and discuss the safety monitoring methodology and the challenges associated with ensuring patient safety in the SLS. Refinements to safety monitoring processes and infrastructure are also discussed. The study results are outside the remit of this paper. The results of the COPD study were published recently and a more in‐depth exploration of the safety results will be the subject of future publications. Achievements The SLS used a linked database system to capture relevant data from primary care practices in Salford and South Manchester, two university hospitals and other national databases. Patient data were collated and analysed to create daily summaries that were used to alert a specialist safety team to potential safety events. Clinical research teams at participating general practitioner sites and pharmacies also captured safety events during routine consultations. Confidence in the safety monitoring processes over time allowed the methodology to be refined and streamlined without compromising patient safety or the timely collection of data. The information technology infrastructure also allowed additional details of safety information to be collected. Conclusion Integration of multiple data sources in the SLS may provide more comprehensive safety information than usually collected in standard randomised controlled trials. Application of the principles of safety monitoring methodology from the SLS could facilitate safety monitoring processes for future pragmatic randomised controlled trials and yield important complementary safety and effectiveness data. © 2016 The Authors Pharmacoepidemiology and Drug Safety Published by John Wiley & Sons Ltd. PMID:27804174

Monitoring safety in a phase III real-world effectiveness trial: use of novel methodology in the Salford Lung Study.

PubMed

Collier, Sue; Harvey, Catherine; Brewster, Jill; Bakerly, Nawar Diar; Elkhenini, Hanaa F; Stanciu, Roxana; Williams, Claire; Brereton, Jacqui; New, John P; McCrae, John; McCorkindale, Sheila; Leather, David

2017-03-01

The Salford Lung Study (SLS) programme, encompassing two phase III pragmatic randomised controlled trials, was designed to generate evidence on the effectiveness of a once-daily treatment for asthma and chronic obstructive pulmonary disease in routine primary care using electronic health records. The objective of this study was to describe and discuss the safety monitoring methodology and the challenges associated with ensuring patient safety in the SLS. Refinements to safety monitoring processes and infrastructure are also discussed. The study results are outside the remit of this paper. The results of the COPD study were published recently and a more in-depth exploration of the safety results will be the subject of future publications. The SLS used a linked database system to capture relevant data from primary care practices in Salford and South Manchester, two university hospitals and other national databases. Patient data were collated and analysed to create daily summaries that were used to alert a specialist safety team to potential safety events. Clinical research teams at participating general practitioner sites and pharmacies also captured safety events during routine consultations. Confidence in the safety monitoring processes over time allowed the methodology to be refined and streamlined without compromising patient safety or the timely collection of data. The information technology infrastructure also allowed additional details of safety information to be collected. Integration of multiple data sources in the SLS may provide more comprehensive safety information than usually collected in standard randomised controlled trials. Application of the principles of safety monitoring methodology from the SLS could facilitate safety monitoring processes for future pragmatic randomised controlled trials and yield important complementary safety and effectiveness data. © 2016 The Authors Pharmacoepidemiology and Drug Safety Published by John Wiley & Sons Ltd. © 2016 The Authors Pharmacoepidemiology and Drug Safety Published by John Wiley & Sons Ltd.

76 FR 33419 - Nationally Recognized Statistical Rating Organizations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-08

... documentation of the internal control structure) or should the factors focus on the design (i.e., establishment... related to implementing them. a. Controls reasonably designed to ensure that a newly developed methodology... U.S.C. 78o-7(r)(1)(A). b. Controls reasonably designed to ensure that a newly developed methodology...

Facts and fiction of learning systems. [decision making intelligent control

NASA Technical Reports Server (NTRS)

Saridis, G. N.

1975-01-01

The methodology that will provide the updated precision for the hardware control and the advanced decision making and planning in the software control is called learning systems and intelligent control. It was developed theoretically as an alternative for the nonsystematic heuristic approaches of artificial intelligence experiments and the inflexible formulation of modern optimal control methods. Its basic concepts are discussed and some feasibility studies of some practical applications are presented.

Clinical results from a noninvasive blood glucose monitor

NASA Astrophysics Data System (ADS)

Blank, Thomas B.; Ruchti, Timothy L.; Lorenz, Alex D.; Monfre, Stephen L.; Makarewicz, M. R.; Mattu, Mutua; Hazen, Kevin

2002-05-01

Non-invasive blood glucose monitoring has long been proposed as a means for advancing the management of diabetes through increased measurement and control. The use of a near-infrared, NIR, spectroscopy based methodology for noninvasive monitoring has been pursued by a number of groups. The accuracy of the NIR measurement technology is limited by challenges related to the instrumentation, the heterogeneity and time-variant nature of skin tissue, and the complexity of the calibration methodology. In this work, we discuss results from a clinical study that targeted the evaluation of individual calibrations for each subject based on a series of controlled calibration visits. While the customization of the calibrations to individuals was intended to reduce model complexity, the extensive requirements for each individual set of calibration data were difficult to achieve and required several days of measurement. Through the careful selection of a small subset of data from all samples collected on the 138 study participants in a previous study, we have developed a methodology for applying a single standard calibration to multiple persons. The standard calibrations have been applied to a plurality of individuals and shown to be persistent over periods greater than 24 weeks.

Display/control requirements for automated VTOL aircraft

NASA Technical Reports Server (NTRS)

Hoffman, W. C.; Kleinman, D. L.; Young, L. R.

1976-01-01

A systematic design methodology for pilot displays in advanced commercial VTOL aircraft was developed and refined. The analyst is provided with a step-by-step procedure for conducting conceptual display/control configurations evaluations for simultaneous monitoring and control pilot tasks. The approach consists of three phases: formulation of information requirements, configuration evaluation, and system selection. Both the monitoring and control performance models are based upon the optimal control model of the human operator. Extensions to the conventional optimal control model required in the display design methodology include explicit optimization of control/monitoring attention; simultaneous monitoring and control performance predictions; and indifference threshold effects. The methodology was applied to NASA's experimental CH-47 helicopter in support of the VALT program. The CH-47 application examined the system performance of six flight conditions. Four candidate configurations are suggested for evaluation in pilot-in-the-loop simulations and eventual flight tests.

Computer-Based Cognitive Training for Executive Functions after Stroke: A Systematic Review

PubMed Central

van de Ven, Renate M.; Murre, Jaap M. J.; Veltman, Dick J.; Schmand, Ben A.

2016-01-01

Background: Stroke commonly results in cognitive impairments in working memory, attention, and executive function, which may be restored with appropriate training programs. Our aim was to systematically review the evidence for computer-based cognitive training of executive dysfunctions. Methods: Studies were included if they concerned adults who had suffered stroke or other types of acquired brain injury, if the intervention was computer training of executive functions, and if the outcome was related to executive functioning. We searched in MEDLINE, PsycINFO, Web of Science, and The Cochrane Library. Study quality was evaluated based on the CONSORT Statement. Treatment effect was evaluated based on differences compared to pre-treatment and/or to a control group. Results: Twenty studies were included. Two were randomized controlled trials that used an active control group. The other studies included multiple baselines, a passive control group, or were uncontrolled. Improvements were observed in tasks similar to the training (near transfer) and in tasks dissimilar to the training (far transfer). However, these effects were not larger in trained than in active control groups. Two studies evaluated neural effects and found changes in both functional and structural connectivity. Most studies suffered from methodological limitations (e.g., lack of an active control group and no adjustment for multiple testing) hampering differentiation of training effects from spontaneous recovery, retest effects, and placebo effects. Conclusions: The positive findings of most studies, including neural changes, warrant continuation of research in this field, but only if its methodological limitations are addressed. PMID:27148007

A computer-aided approach to nonlinear control systhesis

NASA Technical Reports Server (NTRS)

Wie, Bong; Anthony, Tobin

1988-01-01

The major objective of this project is to develop a computer-aided approach to nonlinear stability analysis and nonlinear control system design. This goal is to be obtained by refining the describing function method as a synthesis tool for nonlinear control design. The interim report outlines the approach by this study to meet these goals including an introduction to the INteractive Controls Analysis (INCA) program which was instrumental in meeting these study objectives. A single-input describing function (SIDF) design methodology was developed in this study; coupled with the software constructed in this study, the results of this project provide a comprehensive tool for design and integration of nonlinear control systems.

Methodological Characteristics and Future Directions for Plyometric Jump Training Research: A Scoping Review.

PubMed

Ramirez-Campillo, Rodrigo; Álvarez, Cristian; García-Hermoso, Antonio; Ramírez-Vélez, Robinson; Gentil, Paulo; Asadi, Abbas; Chaabene, Helmi; Moran, Jason; Meylan, Cesar; García-de-Alcaraz, Antonio; Sanchez-Sanchez, Javier; Nakamura, Fabio Y; Granacher, Urs; Kraemer, William; Izquierdo, Mikel

2018-05-01

Recently, there has been a proliferation of published articles on the effect of plyometric jump training, including several review articles and meta-analyses. However, these types of research articles are generally of narrow scope. Furthermore, methodological limitations among studies (e.g., a lack of active/passive control groups) prevent the generalization of results, and these factors need to be addressed by researchers. On that basis, the aims of this scoping review were to (1) characterize the main elements of plyometric jump training studies (e.g., training protocols) and (2) provide future directions for research. From 648 potentially relevant articles, 242 were eligible for inclusion in this review. The main issues identified related to an insufficient number of studies conducted in females, youths, and individual sports (~ 24.0, ~ 37.0, and ~ 12.0% of overall studies, respectively); insufficient reporting of effect size values and training prescription (~ 34.0 and ~ 55.0% of overall studies, respectively); and studies missing an active/passive control group and randomization (~ 40.0 and ~ 20.0% of overall studies, respectively). Furthermore, plyometric jump training was often combined with other training methods and added to participants' daily training routines (~ 47.0 and ~ 39.0% of overall studies, respectively), thus distorting conclusions on its independent effects. Additionally, most studies lasted no longer than 7 weeks. In future, researchers are advised to conduct plyometric training studies of high methodological quality (e.g., randomized controlled trials). More research is needed in females, youth, and individual sports. Finally, the identification of specific dose-response relationships following plyometric training is needed to specifically tailor intervention programs, particularly in the long term.

The Utility of Case-Control Methods for Health Policy and Planning Analysis: An Illustration from Kinshasa, Zaire.

ERIC Educational Resources Information Center

Mock, Nancy B.; And Others

1993-01-01

The use of case-control methodology as an applied policy/planning research tool in assessing the potential effectiveness of behavioral interventions is studied in connection with diarrhea control in Zaire. Results with 107 matched pairs of children demonstrate the importance of hygiene-related knowledge and the utility of the research approach.…

Methodological quality of quantitative lesbian, gay, bisexual, and transgender nursing research from 2000 to 2010.

PubMed

Johnson, Michael; Smyer, Tish; Yucha, Carolyn

2012-01-01

The purpose of this study was to evaluate the methodological quality of quantitative lesbian, gay, bisexual, and transgender nursing research from 2000 to 2010. Using a key word search in Cumulative Index to Nursing and Allied Health Literature, 188 studies were identified and 40 met the criteria, which included descriptive, experimental, quasi-experimental, or observational (case control, cohort, and cross-sectional) design. The methodological quality of these studies was similar to that reported for medical and nursing educational research. The foci of these lesbian, gay, bisexual, and transgender studies were biased toward human immunodeficiency virus, acquired immunodeficiency syndrome, and sexually transmitted diseases, and 58.5% of the funded research was related to human immunodeficiency virus or acquired immunodeficiency syndrome. To provide evidence-based health care to these populations, an understanding of the current state of research is crucial.

The role of structural characteristics in video-game play motivation: a Q-methodology study.

PubMed

Westwood, Dave; Griffiths, Mark D

2010-10-01

Until recently, there has been very little naturalistic study of what gaming experiences are like, and how gaming fits into people's lives. Using a recently developed structural characteristic taxonomy of video games, this study examined the psycho-structural elements of computer games that motivate gamers to play them. Using Q-Sort methodology, 40 gamers participated in an online Q-sort task. Results identified six distinct types of gamers based on the factors generated: (a) story-driven solo gamers; (b) social gamers; (c) solo limited gamers; (d) hardcore online gamers; (e) solo control/identity gamers; and (f ) casual gamers. These gaming types are discussed, and a brief evaluation of similar and unique elements of the different types of gamer is also offered. The current study shows Q-methodology to be a relevant and applicable method in the psychological research of gaming.

A methodology for post-EIS (environmental impact statement) monitoring

USGS Publications Warehouse

Marcus, Linda Graves

1979-01-01

A methodology for monitoring the impacts predicted in environmental impact statements (EIS's) was developed using the EIS on phosphate development in southeastern Idaho as a case study. A monitoring system based on this methodology: (1) coordinates a comprehensive, intergovernmental monitoring effort; (2) documents the major impacts that result, thereby improving the accuracy of impact predictions in future EIS's; (3) helps agencies control impacts by warning them when critical impact levels are reached and by providing feedback on the success of mitigating measures; and (4) limits monitoring data to the essential information that agencies need to carry out their regulatory and environmental protection responsibilities. The methodology is presented as flow charts accompanied by tables that describe the objectives, tasks, and products for each work element in the flow chart.

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…

Modified Dynamic Inversion to Control Large Flexible Aircraft: What's Going On?

NASA Technical Reports Server (NTRS)

Gregory, Irene M.

1999-01-01

High performance aircraft of the future will be designed lighter, more maneuverable, and operate over an ever expanding flight envelope. One of the largest differences from the flight control perspective between current and future advanced aircraft is elasticity. Over the last decade, dynamic inversion methodology has gained considerable popularity in application to highly maneuverable fighter aircraft, which were treated as rigid vehicles. This paper explores dynamic inversion application to an advanced highly flexible aircraft. An initial application has been made to a large flexible supersonic aircraft. In the course of controller design for this advanced vehicle, modifications were made to the standard dynamic inversion methodology. The results of this application were deemed rather promising. An analytical study has been undertaken to better understand the nature of the made modifications and to determine its general applicability. This paper presents the results of this initial analytical look at the modifications to dynamic inversion to control large flexible aircraft.

The Complex Nature of Bilinguals' Language Usage Modulates Task-Switching Outcomes

PubMed Central

Yang, Hwajin; Hartanto, Andree; Yang, Sujin

2016-01-01

In view of inconsistent findings regarding bilingual advantages in executive functions (EF), we reviewed the literature to determine whether bilinguals' different language usage causes measureable changes in the shifting aspects of EF. By drawing on the theoretical framework of the adaptive control hypothesis—which postulates a critical link between bilinguals' varying demands on language control and adaptive cognitive control (Green and Abutalebi, 2013), we examined three factors that characterize bilinguals' language-switching experience: (a) the interactional context of conversational exchanges, (b) frequency of language switching, and (c) typology of code-switching. We also examined whether methodological variations in previous task-switching studies modulate task-specific demands on control processing and lead to inconsistencies in the literature. Our review demonstrates that not only methodological rigor but also a more finely grained, theory-based approach will be required to understand the cognitive consequences of bilinguals' varied linguistic practices in shifting EF. PMID:27199800

Optimal Micro-Vane Flow Control for Compact Air Vehicle Inlets

NASA Technical Reports Server (NTRS)

Anderson, Bernhard H.; Miller, Daniel N.; Addington, Gregory A.; Agrell, Johan

2004-01-01

The purpose of this study on micro-vane secondary flow control is to demonstrate the viability and economy of Response Surface Methodology (RSM) to optimally design micro-vane secondary flow control arrays, and to establish that the aeromechanical effects of engine face distortion can also be included in the design and optimization process. These statistical design concepts were used to investigate the design characteristics of "low unit strength" micro-effector arrays. "Low unit strength" micro-effectors are micro-vanes set at very low angles-of-incidence with very long chord lengths. They were designed to influence the near wall inlet flow over an extended streamwise distance, and their advantage lies in low total pressure loss and high effectiveness in managing engine face distortion. Therefore, this report examines optimal micro-vane secondary flow control array designs for compact inlets through a Response Surface Methodology.

Living Animals in the Classroom: A Meta-Analysis on Learning Outcome and a Treatment-Control Study Focusing on Knowledge and Motivation

ERIC Educational Resources Information Center

Hummel, Eberhard; Randler, Christoph

2012-01-01

Prior research states that the use of living animals in the classroom leads to a higher knowledge but those previous studies have methodological and statistical problems. We applied a meta-analysis and developed a treatment-control study in a middle school classroom. The treatments (film vs. living animal) differed only by the presence of the…

Designing Measurement Studies under Budget Constraints: Controlling Error of Measurement and Power.

ERIC Educational Resources Information Center

Marcoulides, George A.

1995-01-01

A methodology is presented for minimizing the mean error variance-covariance component in studies with resource constraints. The method is illustrated using a one-facet multivariate design. Extensions to other designs are discussed. (SLD)

Is reflexology an effective intervention? A systematic review of randomised controlled trials.

PubMed

Ernst, Edzard

2009-09-07

To evaluate the evidence for and against the effectiveness of reflexology for treating any medical condition. Six electronic databases were searched from their inception to February 2009 to identify all relevant randomised controlled trials (RCTs). No language restrictions were applied. RCTs of reflexology delivered by trained reflexologists to patients with specific medical conditions. Condition studied, study design and controls, primary outcome measures, follow-up, and main results were extracted. 18 RCTs met all the inclusion criteria. The studies examined a range of conditions: anovulation, asthma, back pain, dementia, diabetes, cancer, foot oedema in pregnancy, headache, irritable bowel syndrome, menopause, multiple sclerosis, the postoperative state and premenstrual syndrome. There were > 1 studies for asthma, the postoperative state, cancer palliation and multiple sclerosis. Five RCTs yielded positive results. Methodological quality was evaluated using the Jadad scale. The methodological quality was often poor, and sample sizes were generally low. Most higher-quality trials did not generate positive findings. The best evidence available to date does not demonstrate convincingly that reflexology is an effective treatment for any medical condition.

Clinical trials in palliative care: a systematic review of their methodological characteristics and of the quality of their reporting.

PubMed

Bouça-Machado, Raquel; Rosário, Madalena; Alarcão, Joana; Correia-Guedes, Leonor; Abreu, Daisy; Ferreira, Joaquim J

2017-01-25

Over the past decades there has been a significant increase in the number of published clinical trials in palliative care. However, empirical evidence suggests that there are methodological problems in the design and conduct of studies, which raises questions about the validity and generalisability of the results and of the strength of the available evidence. We sought to evaluate the methodological characteristics and assess the quality of reporting of clinical trials in palliative care. We performed a systematic review of published clinical trials assessing therapeutic interventions in palliative care. Trials were identified using MEDLINE (from its inception to February 2015). We assessed methodological characteristics and describe the quality of reporting using the Cochrane Risk of Bias tool. We retrieved 107 studies. The most common medical field studied was oncology, and 43.9% of trials evaluated pharmacological interventions. Symptom control and physical dimensions (e.g. intervention on pain, breathlessness, nausea) were the palliative care-specific issues most studied. We found under-reporting of key information in particular on random sequence generation, allocation concealment, and blinding. While the number of clinical trials in palliative care has increased over time, methodological quality remains suboptimal. This compromises the quality of studies. Therefore, a greater effort is needed to enable the appropriate performance of future studies and increase the robustness of evidence-based medicine in this important field.

Control Law Design in a Computational Aeroelasticity Environment

NASA Technical Reports Server (NTRS)

Newsom, Jerry R.; Robertshaw, Harry H.; Kapania, Rakesh K.

2003-01-01

A methodology for designing active control laws in a computational aeroelasticity environment is given. The methodology involves employing a systems identification technique to develop an explicit state-space model for control law design from the output of a computational aeroelasticity code. The particular computational aeroelasticity code employed in this paper solves the transonic small disturbance aerodynamic equation using a time-accurate, finite-difference scheme. Linear structural dynamics equations are integrated simultaneously with the computational fluid dynamics equations to determine the time responses of the structure. These structural responses are employed as the input to a modern systems identification technique that determines the Markov parameters of an "equivalent linear system". The Eigensystem Realization Algorithm is then employed to develop an explicit state-space model of the equivalent linear system. The Linear Quadratic Guassian control law design technique is employed to design a control law. The computational aeroelasticity code is modified to accept control laws and perform closed-loop simulations. Flutter control of a rectangular wing model is chosen to demonstrate the methodology. Various cases are used to illustrate the usefulness of the methodology as the nonlinearity of the aeroelastic system is increased through increased angle-of-attack changes.

Methodological Issues in the Study of Air Force Organizational Structures,

DTIC Science & Technology

MOTIVATION, MORALE, PERFORMANCE(HUMAN), LEADERSHIP , SKILLS, MANAGEMENT PLANNING AND CONTROL, MODEL THEORY , SYMPOSIA...RESOURCE MANAGEMENT , *HUMAN RESOURCES, *MANPOWER UTILIZATION, *JOB ANALYSIS, *ORGANIZATIONS, STRUCTURES, PERSONNEL MANAGEMENT , DECISION MAKING

A protocol for a systematic review of non-randomised evaluations of strategies to improve participant recruitment to randomised controlled trials.

PubMed

Gardner, Heidi R; Fraser, Cynthia; MacLennan, Graeme; Treweek, Shaun

2016-08-02

Randomised controlled trials guard against selection bias and therefore offer the fairest way of evaluating healthcare interventions such as medicinal products, devices and services. Recruitment to trials can be extremely difficult, and poor recruitment can lead to extensions to both time and budget and may result in an underpowered study which does not satisfactorily answer the original research question. In the worst cases, a trial may be abandoned, causing huge waste. The evidence to support the choice of recruitment interventions is currently weak. Non-randomised evaluations of recruitment interventions are currently rejected on grounds of poor methodological quality, but systematic evaluation and assessment of this substantial body of work (using Grading of Recommendations Assessment, Development and Evaluation (GRADE) where possible) may provide useful information to support and inform the recruitment decisions of trialists and the research priorities of methodology researchers. The following databases will be searched for relevant studies: Cochrane Methodology Register, MEDLINE, EMBASE, CINAHL and PsycINFO. Any non-randomised study that includes a comparison of two or more interventions to improve recruitment to randomised controlled trials will be included. We will not apply any restrictions on publication date, language or journal. The primary outcome will be the number of individuals or centres recruited into a randomised controlled trial. The secondary outcome will be cost per recruit. Two reviewers will independently screen abstracts for eligible studies, and then, full texts of potentially relevant records will be reviewed. Disagreements will be resolved through discussion. The methodological quality of studies will be assessed using the Cochrane risk of bias tool for non-randomised studies, and the GRADE system will be used if studies are pooled. This review aims to summarise the evidence on methods used to improve recruitment to randomised controlled trials. Carrying out a systematic review including only data from non-randomised studies is a novel approach, and one which some may argue is futile. However, we believe that the systematic evaluation of what is likely to be a substantial amount of research activity is necessary, worthwhile, and will yield valuable results for the clinical trials community regardless of whether the outcomes find in favour of one or more interventions. Should the results of this review suggest that non-randomised evaluations do have something to offer trialists planning their recruitment strategies, the review may be combined in the future with the Cochrane review of randomised evaluations to produce a full review of recruitment strategies encompassing both randomised and non-randomised evaluation methods. PROSPERO CRD42016037718.

Public Health Interventions for Aedes Control in the Time of Zikavirus– A Meta-Review on Effectiveness of Vector Control Strategies

PubMed Central

Bouzid, Maha; Brainard, Julii; Hooper, Lee; Hunter, Paul R.

2016-01-01

Background There is renewed interest in effective measures to control Zika and dengue vectors. A synthesis of published literature with a focus on the quality of evidence is warranted to determine the effectiveness of vector control strategies. Methodology We conducted a meta-review assessing the effectiveness of any Aedes control measure. We searched Scopus and Medline for relevant reviews through to May 2016. Titles, abstracts and full texts were assessed independently for inclusion by two authors. Data extraction was performed in duplicate and validity of the evidence was assessed using GRADE criteria. Findings 13 systematic reviews that investigated the effect of control measures on entomological parameters or disease incidence were included. Biological controls seem to achieve better reduction of entomological indices than chemical controls, while educational campaigns can reduce breeding habitats. Integrated vector control strategies may not always increase effectiveness. The efficacy of any control programme is dependent on local settings, intervention type, resources and study duration, which may partly explain the varying degree of success between studies. Nevertheless, the quality of evidence was mostly low to very low due to poor reporting of study design, observational methodologies, heterogeneity, and indirect outcomes, thus hindering an evidence-based recommendation. Conclusions The evidence for the effectiveness of Aedes control measures is mixed. Chemical control, which is commonly used, does not appear to be associated with sustainable reductions of mosquito populations over time. Indeed, by contributing to a false sense of security, chemical control may reduce the effectiveness of educational interventions aimed at encouraging local people to remove mosquito breeding sites. Better quality studies of the impact of vector control interventions on the incidence of human infections with Dengue or Zika are still needed. PMID:27926934

Measurement properties of the upright motor control test for adults with stroke: a systematic review.

PubMed

Gorgon, Edward James R; Lazaro, Rolando T

2016-01-01

The Upright Motor Control Test (UMCT) has been used in clinical practice and research to assess functional strength of the hemiparetic lower limb in adults with stroke. It is unclear if evidence is sufficient to warrant its use. The purpose of this systematic review was to synthesize available evidence on the measurement properties of the UMCT for stroke rehabilitation. Electronic databases that indexed biomedical literature were systematically searched from inception until October 2015 (week 4): Embase, PubMed, Web of Science, CINAHL, PEDro, Cochrane Library, Scopus, ScienceDirect, SPORTDiscus, LILACS, DOAJ, and Google Scholar. All studies that had used the UMCT in the time period covered underwent hand searching for any additional study. Observational studies involving adults with stroke that explored any measurement property of the UMCT were included. The COnsensus-based Standards for the selection of health Measurement INstruments was used to assess the methodological quality of included studies. The CanChild Outcome Measures Rating Form was used for extracting data on measurement properties and clinical utility. The search yielded three methodologic studies that addressed criterion-related validity and contruct validity. Two studies of fair methodological quality demonstrated moderate-level evidence that Knee Extension and Knee Flexion subtest scores were predictive of community-level and household-level ambulation. One study of fair methodological quality provided limited-level evidence for the correlation of Knee Extension subtest scores with a laboratory measure of ground reaction forces. No published studies formally assessed reliability, responsiveness, or clinical utility. Limited information on responsiveness and clinical utility dimensions could be inferred from the included studies. The UMCT is a practical assessment tool for voluntary control or functional strength of the hemiparetic lower limb in standing in adults with stroke. Although different levels of evidence suggest that the Knee Extension and Knee Flexion subtests may possess criterion and construct validity, the lack of published literature examining content validity, reliability, and responsiveness raises questions regarding the use of the UMCT in routine clinical practice. These key findings highlight the need to further investigate the UMCT's measurement properties toward enhancing its standardization.

Nonlinear maneuver autopilot for the F-15 aircraft

NASA Technical Reports Server (NTRS)

Menon, P. K. A.; Badgett, M. E.; Walker, R. A.

1989-01-01

A methodology is described for the development of flight test trajectory control laws based on singular perturbation methodology and nonlinear dynamic modeling. The control design methodology is applied to a detailed nonlinear six degree-of-freedom simulation of the F-15 and results for a level accelerations, pushover/pullup maneuver, zoom and pushover maneuver, excess thrust windup turn, constant thrust windup turn, and a constant dynamic pressure/constant load factor trajectory are presented.

Improved methodology to assess modification and completion of landfill gas management in the aftercare period

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

Morris, Jeremy W.F., E-mail: jmorris@geosyntec.com; Crest, Marion, E-mail: marion.crest@suez-env.com; Barlaz, Morton A., E-mail: barlaz@ncsu.edu

Highlights: Black-Right-Pointing-Pointer Performance-based evaluation of landfill gas control system. Black-Right-Pointing-Pointer Analytical framework to evaluate transition from active to passive gas control. Black-Right-Pointing-Pointer Focus on cover oxidation as an alternative means of passive gas control. Black-Right-Pointing-Pointer Integrates research on long-term landfill behavior with practical guidance. - Abstract: Municipal solid waste landfills represent the dominant option for waste disposal in many parts of the world. While some countries have greatly reduced their reliance on landfills, there remain thousands of landfills that require aftercare. The development of cost-effective strategies for landfill aftercare is in society's interest to protect human health and the environmentmore » and to prevent the emergence of landfills with exhausted aftercare funding. The Evaluation of Post-Closure Care (EPCC) methodology is a performance-based approach in which landfill performance is assessed in four modules including leachate, gas, groundwater, and final cover. In the methodology, the objective is to evaluate landfill performance to determine when aftercare monitoring and maintenance can be reduced or possibly eliminated. This study presents an improved gas module for the methodology. While the original version of the module focused narrowly on regulatory requirements for control of methane migration, the improved gas module also considers best available control technology for landfill gas in terms of greenhouse gas emissions, air quality, and emissions of odoriferous compounds. The improved module emphasizes the reduction or elimination of fugitive methane by considering the methane oxidation capacity of the cover system. The module also allows for the installation of biologically active covers or other features designed to enhance methane oxidation. A methane emissions model, CALMIM, was used to assist with an assessment of the methane oxidation capacity of landfill covers.« less

A Practical Risk Assessment Methodology for Safety-Critical Train Control Systems

DOT National Transportation Integrated Search

2009-07-01

This project proposes a Practical Risk Assessment Methodology (PRAM) for analyzing railroad accident data and assessing the risk and benefit of safety-critical train control systems. This report documents in simple steps the algorithms and data input...

[Methodological problems in the use of information technologies in physical education].

PubMed

Martirosov, E G; Zaĭtseva, G A

2000-01-01

The paper considers methodological problems in the use of computer technologies in physical education by applying diagnostic and consulting systems, educational and educational-and-training process automation systems, and control and self-control programmes for athletes and others.

SCI Hazard Report Methodology

NASA Technical Reports Server (NTRS)

Mitchell, Michael S.

2010-01-01

This slide presentation reviews the methodology in creating a Source Control Item (SCI) Hazard Report (HR). The SCI HR provides a system safety risk assessment for the following Ares I Upper Stage Production Contract (USPC) components (1) Pyro Separation Systems (2) Main Propulsion System (3) Reaction and Roll Control Systems (4) Thrust Vector Control System and (5) Ullage Settling Motor System components.

Journal impact factor and methodological quality of surgical randomized controlled trials: an empirical study.

PubMed

Ahmed Ali, Usama; Reiber, Beata M M; Ten Hove, Joren R; van der Sluis, Pieter C; Gooszen, Hein G; Boermeester, Marja A; Besselink, Marc G

2017-11-01

The journal impact factor (IF) is often used as a surrogate marker for methodological quality. The objective of this study is to evaluate the relation between the journal IF and methodological quality of surgical randomized controlled trials (RCTs). Surgical RCTs published in PubMed in 1999 and 2009 were identified. According to IF, RCTs were divided into groups of low (<2), median (2-3) and high IF (>3), as well as into top-10 vs all other journals. Methodological quality characteristics and factors concerning funding, ethical approval and statistical significance of outcomes were extracted and compared between the IF groups. Additionally, a multivariate regression was performed. The median IF was 2.2 (IQR 2.37). The percentage of 'low-risk of bias' RCTs was 13% for top-10 journals vs 4% for other journals in 1999 (P < 0.02), and 30 vs 12% in 2009 (P < 0.02). Similar results were observed for high vs low IF groups. The presence of sample-size calculation, adequate generation of allocation and intention-to-treat analysis were independently associated with publication in higher IF journals; as were multicentre trials and multiple authors. Publication of RCTs in high IF journals is associated with moderate improvement in methodological quality compared to RCTs published in lower IF journals. RCTs with adequate sample-size calculation, generation of allocation or intention-to-treat analysis were associated with publication in a high IF journal. On the other hand, reporting a statistically significant outcome and being industry funded were not independently associated with publication in a higher IF journal.

Challenges to inferring causality from viral information dispersion in dynamic social networks

NASA Astrophysics Data System (ADS)

Ternovski, John

2014-06-01

Understanding the mechanism behind large-scale information dispersion through complex networks has important implications for a variety of industries ranging from cyber-security to public health. With the unprecedented availability of public data from online social networks (OSNs) and the low cost nature of most OSN outreach, randomized controlled experiments, the "gold standard" of causal inference methodologies, have been used with increasing regularity to study viral information dispersion. And while these studies have dramatically furthered our understanding of how information disseminates through social networks by isolating causal mechanisms, there are still major methodological concerns that need to be addressed in future research. This paper delineates why modern OSNs are markedly different from traditional sociological social networks and why these differences present unique challenges to experimentalists and data scientists. The dynamic nature of OSNs is particularly troublesome for researchers implementing experimental designs, so this paper identifies major sources of bias arising from network mutability and suggests strategies to circumvent and adjust for these biases. This paper also discusses the practical considerations of data quality and collection, which may adversely impact the efficiency of the estimator. The major experimental methodologies used in the current literature on virality are assessed at length, and their strengths and limits identified. Other, as-yetunsolved threats to the efficiency and unbiasedness of causal estimators--such as missing data--are also discussed. This paper integrates methodologies and learnings from a variety of fields under an experimental and data science framework in order to systematically consolidate and identify current methodological limitations of randomized controlled experiments conducted in OSNs.

Methodological quality of randomised controlled trials in burns care. A systematic review.

PubMed

Danilla, Stefan; Wasiak, Jason; Searle, Susana; Arriagada, Cristian; Pedreros, Cesar; Cleland, Heather; Spinks, Anneliese

2009-11-01

To evaluate the methodological quality of published randomised controlled trials (RCTs) in burn care treatment and management. Using a predetermined search strategy we searched Ovid MEDLINE (1950 to January 2008) database to identify all English RCTs related to burn care. Full text studies identified were reviewed for key demographic and methodological characteristics. Methodological trial quality was assessed using the Jadad scale. A total of 257 studies involving 14,535 patients met the inclusion criteria. The median Jadad score was 2 (out of a best possible score of 5). Information was given in the introduction and discussion sections of most RCTs, although insufficient detail was provided on randomisation, allocation concealment, and blinding. The number of RCTs increased between 1950 and 2008 (Spearman's rho=0.6129, P<0.001), although the reporting quality did not improve over the same time period (P=0.1896) and was better in RCTs with larger sample sizes (median Jadad score, 4 vs. 2 points, P<0.0001). Methodological quality did not correlate with journal impact factor (P=0.2371). The reporting standards of RCTs are highly variable and less than optimal in most cases. The advent of evidence-based medicine heralds a new approach to burns care and systematic steps are needed to improve the quality of RCTs in this field. Identifying and reviewing the existing number of RCTs not only highlights the need for burn clinicians to conduct more trials, but may also encourage burn health clinicians to consider the importance of conducting trials that follow appropriate, evidence-based standards.

Lean management in health care: definition, concepts, methodology and effects reported (systematic review protocol).

PubMed

Lawal, Adegboyega K; Rotter, Thomas; Kinsman, Leigh; Sari, Nazmi; Harrison, Liz; Jeffery, Cathy; Kutz, Mareike; Khan, Mohammad F; Flynn, Rachel

2014-09-19

Lean is a set of operating philosophies and methods that help create a maximum value for patients by reducing waste and waits. It emphasizes the consideration of the customer's needs, employee involvement and continuous improvement. Research on the application and implementation of lean principles in health care has been limited. This is a protocol for a systematic review, following the Cochrane Effective Practice and Organisation of Care (EPOC) methodology. The review aims to document, catalogue and synthesize the existing literature on the effects of lean implementation in health care settings especially the potential effects on professional practice and health care outcomes. We have developed a Medline keyword search strategy, and this focused strategy will be translated into other databases. All search strategies will be provided in the review. The method proposed by the Cochrane EPOC group regarding randomized study designs, non-randomised controlled trials controlled before and after studies and interrupted time series will be followed. In addition, we will also include cohort, case-control studies, and relevant non-comparative publications such as case reports. We will categorize and analyse the review findings according to the study design employed, the study quality (low- versus high-quality studies) and the reported types of implementation in the primary studies. We will present the results of studies in a tabular form. Overall, the systematic review aims to identify, assess and synthesize the evidence to underpin the implementation of lean activities in health care settings as defined in this protocol. As a result, the review will provide an evidence base for the effectiveness of lean and implementation methodologies reported in health care. PROSPERO CRD42014008853.

Lean management in health care: definition, concepts, methodology and effects reported (systematic review protocol)

PubMed Central

2014-01-01

Background Lean is a set of operating philosophies and methods that help create a maximum value for patients by reducing waste and waits. It emphasizes the consideration of the customer’s needs, employee involvement and continuous improvement. Research on the application and implementation of lean principles in health care has been limited. Methods This is a protocol for a systematic review, following the Cochrane Effective Practice and Organisation of Care (EPOC) methodology. The review aims to document, catalogue and synthesize the existing literature on the effects of lean implementation in health care settings especially the potential effects on professional practice and health care outcomes. We have developed a Medline keyword search strategy, and this focused strategy will be translated into other databases. All search strategies will be provided in the review. The method proposed by the Cochrane EPOC group regarding randomized study designs, non-randomised controlled trials controlled before and after studies and interrupted time series will be followed. In addition, we will also include cohort, case–control studies, and relevant non-comparative publications such as case reports. We will categorize and analyse the review findings according to the study design employed, the study quality (low- versus high-quality studies) and the reported types of implementation in the primary studies. We will present the results of studies in a tabular form. Discussion Overall, the systematic review aims to identify, assess and synthesize the evidence to underpin the implementation of lean activities in health care settings as defined in this protocol. As a result, the review will provide an evidence base for the effectiveness of lean and implementation methodologies reported in health care. Systematic review registration PROSPERO CRD42014008853 PMID:25238974

Benzene Case Study Final Report - Second Prospective Report Study Science Advisory Board Review, July 2009

EPA Pesticide Factsheets

EPA developed a methodology for estimating the health benefits of benzene reductions and has applied it in a metropolitan-scale case study of the benefits of CAA controls on benzene emissions to accompany the main 812 analysis.

Draft Benzene Case Study Review - Second Prospective Report Study Science Advisory Board Review, March 2008

EPA Pesticide Factsheets

EPA developed a methodology for estimating the health benefits of benzene reductions and has applied it in a metropolitan-scale case study of the benefits of CAA controls on benzene emissions to accompany the main 812 analysis.

A methodology based on insecticide impregnated filter paper for monitoring resistance to deltamethrin in Triatoma infestans field populations.

PubMed

Remón, C; Lobbia, P; Zerba, E; Mougabure-Cueto, G

2017-12-01

The domiciliary presence of Triatoma infestans (Klug) (Hemiptera: Reduviidae) after control interventions was reported in recent years. Toxicological studies showed high levels of resistance to pyrethroids suggesting resistance as one of the main causes of deficient control. The aim of the present study was to develop a protocol to test resistance to deltamethrin in T. infestans collected from the field by discriminate concentration. To evaluate field insects, the effect of age (early vs. later) and nutritional state (starved vs. fed) on the deltamethrin susceptibility of each developmental stage was studied. Topical and insecticide impregnated paper bioassays were used. Using the impregnated paper, the susceptibility to deltamethrin was not affected by the age of the stadium and the nutritional states, and varied with the post-exposure time and with the different developmental stages. A discriminant concentration of deltamethrin (0.36% w/v) impregnated in filter paper was established for all developmental stages. Finally, the methodology and the discriminant concentration were evaluated in the laboratory showing high sensitivity in the discrimination of resistance. The present study developed a methodology of exposure to insecticide impregnated papers and proposes a protocol to test T. infestans in field populations with the aim to detect early evolution of resistance to deltamethrin. © 2017 The Royal Entomological Society.

Critical issues in ALS case-control studies: the case of the Euro-MOTOR study.

PubMed

D'Ovidio, Fabrizio; Rooney, James P K; Visser, Anne E; Vermeulen, Roel C H; Veldink, Jan H; Van Den Berg, Leonard H; Hardiman, Orla; Logroscino, Giancarlo; Chiò, Adriano; Beghi, Ettore

2017-08-01

Backround: Political and sociocultural differences between countries can affect the outcome of clinical and epidemiological studies in ALS. Cross-national studies represent the ideal process by which risk factors can be assessed using the same methodology in different geographical areas. A survey of three European countries (The Netherlands, Ireland and Italy) has been conducted in which incident ALS patients and matched controls were recruited in a population-based study based on age, gender and area of residency, under the Euro-MOTOR systems biology programme of research. We have identified strengths and limitations during the trajectory of the Euro-MOTOR study, from the research design to data analysis. We have analysed the implications of factors including cross-national differences in healthcare systems, sample size, types of matching, the definition of exposures and statistical analysis. Addressing critical methodological aspects of the design of the Euro-MOTOR project minimises bias and will facilitate scientific assessment of the independent role of well-defined exposures.

Postoperative cognitive dysfunction and its relationship to cognitive reserve in elderly total joint replacement patients.

PubMed

Scott, J E; Mathias, J L; Kneebone, A C; Krishnan, J

2017-06-01

Whether total joint replacement (TJR) patients are susceptible to postoperative cognitive dysfunction (POCD) remains unclear due to inconsistencies in research methodologies. Moreover, cognitive reserve may moderate the development of POCD after TJR, but has not been investigated in this context. The current study investigated POCD after TJR, and its relationship with cognitive reserve, using a more rigorous methodology than has previously been utilized. Fifty-three older adults (aged 50+) scheduled for TJR were assessed pre and post surgery (6 months). Forty-five healthy controls matched for age, gender, and premorbid IQ were re-assessed after an equivalent interval. Cognition, cognitive reserve, and physical and mental health were all measured. Standardized regression-based methods were used to assess cognitive changes, while controlling for the confounding effect of repeated cognitive testing. TJR patients only demonstrated a significant decline in Trail Making Test Part B (TMT B) performance, compared to controls. Cognitive reserve only predicted change in TMT B scores among a subset of TJR patients. Specifically, patients who showed the most improvement pre to post surgery had significantly higher reserve than those who showed the greatest decline. The current study provides limited evidence of POCD after TJR when examined using a rigorous methodology, which controlled for practice effects. Cognitive reserve only predicted performance within a subset of the TJR sample. However, the role of reserve in more cognitively compromised patients remains to be determined.

Health-Related Quality of Life in Non–Small-Cell Lung Cancer: An Update of a Systematic Review on Methodologic Issues in Randomized Controlled Trials

PubMed Central

Claassens, Lily; van Meerbeeck, Jan; Coens, Corneel; Quinten, Chantal; Ghislain, Irina; Sloan, Elizabeth K.; Wang, Xin Shelly; Velikova, Galina; Bottomley, Andrew

2011-01-01

Purpose This study is an update of a systematic review of health-related quality-of-life (HRQOL) methodology reporting in non–small-cell lung cancer (NSCLC) randomized controlled trials (RCTs). The objective was to evaluate HRQOL methodology reporting over the last decade and its benefit for clinical decision making. Methods A MEDLINE systematic literature review was performed. Eligible RCTs implemented patient-reported HRQOL assessments and regular oncology treatments for newly diagnosed adult patients with NSCLC. Included studies were published in English from August 2002 to July 2010. Two independent reviewers evaluated all included RCTs. Results Fifty-three RCTs were assessed. Of the 53 RCTs, 81% reported that there was no significant difference in overall survival (OS). However, 50% of RCTs that were unable to find OS differences reported a significant difference in HRQOL scores. The quality of HRQOL reporting has improved; both reporting of clinically significant differences and statistical testing of HRQOL have improved. A European Organisation for Research and Treatment of Cancer HRQOL questionnaire was used in 57% of the studies. However, reporting of HRQOL hypotheses and rationales for choosing HRQOL instruments were significantly less than before 2002 (P < .05). Conclusion The number of NSCLC RCTs incorporating HRQOL assessments has considerably increased. HRQOL continues to demonstrate its importance in RCTs, especially in those studies in which no OS difference is found. Despite the improved quality of HRQOL methodology reporting, certain aspects remain underrepresented. Our findings suggest need for an international standardization of HRQOL reporting similar to the CONSORT guidelines for clinical findings. PMID:21464420

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.

Integrated structure/control design - Present methodology and future opportunities

NASA Technical Reports Server (NTRS)

Weisshaar, T. A.; Newsom, J. R.; Zeiler, T. A.; Gilbert, M. G.

1986-01-01

Attention is given to current methodology applied to the integration of the optimal design process for structures and controls. Multilevel linear decomposition techniques proved to be most effective in organizing the computational efforts necessary for ISCD (integrated structures and control design) tasks. With the development of large orbiting space structures and actively controlled, high performance aircraft, there will be more situations in which this concept can be applied.

A PDE-based methodology for modeling, parameter estimation and feedback control in structural and structural acoustic systems

NASA Technical Reports Server (NTRS)

Banks, H. T.; Brown, D. E.; Metcalf, Vern L.; Silcox, R. J.; Smith, Ralph C.; Wang, Yun

1994-01-01

A problem of continued interest concerns the control of vibrations in a flexible structure and the related problem of reducing structure-borne noise in structural acoustic systems. In both cases, piezoceramic patches bonded to the structures have been successfully used as control actuators. Through the application of a controlling voltage, the patches can be used to reduce structural vibrations which in turn lead to methods for reducing structure-borne noise. A PDE-based methodology for modeling, estimating physical parameters, and implementing a feedback control scheme for problems of this type is discussed. While the illustrating example is a circular plate, the methodology is sufficiently general so as to be applicable in a variety of structural and structural acoustic systems.

Operational Impacts of Wind Energy Resources in the Bonneville Power Administration Control Area - Phase I Report

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

Makarov, Yuri V.; Lu, Shuai

2008-07-15

This report presents a methodology developed to study the future impact of wind on BPA power system load following and regulation requirements. The methodology uses historical data and stochastic processes to simulate the load balancing processes in the BPA power system, by mimicking the actual power system operations. Therefore, the results are close to reality, yet the study based on this methodology is convenient to conduct. Compared with the proposed methodology, existing methodologies for doing similar analysis include dispatch model simulation and standard deviation evaluation on load and wind data. Dispatch model simulation is constrained by the design of themore » dispatch program, and standard deviation evaluation is artificial in separating the load following and regulation requirements, both of which usually do not reflect actual operational practice. The methodology used in this study provides not only capacity requirement information, it also analyzes the ramp rate requirements for system load following and regulation processes. The ramp rate data can be used to evaluate generator response/maneuverability requirements, which is another necessary capability of the generation fleet for the smooth integration of wind energy. The study results are presented in an innovative way such that the increased generation capacity or ramp requirements are compared for two different years, across 24 hours a day. Therefore, the impact of different levels of wind energy on generation requirements at different times can be easily visualized.« less

What is covered by "cancer rehabilitation" in PubMed? A review of randomized controlled trials 1990-2011.

PubMed

Gudbergsson, Sævar Berg; Dahl, Alv A; Loge, Jon Håvard; Thorsen, Lene; Oldervoll, Line M; Grov, Ellen K

2015-02-01

This focused review examines randomized controlled studies included by the term "cancer rehabilitation" in PubMed. The research questions concern the type of interventions performed and their methodological quality. Using the Medical Subject Headings (MeSH) terms: neoplasm AND rehabilitation, all articles with randomized controlled studies that included adult cancer patients, written in English, were extracted from PubMed. Papers covering physical exercise, psychiatric/psychological treatment or social support only were excluded as they had been reviewed recently. Abstracts and papers were assessed by 3 pairs of reviewers, and descriptive information was extracted systematically. Methodological quality was rated on a 10-item index scale, and the cut-off for acceptable quality was set at ≥ 8. A total of 132 (19%) of the 683 identified papers met the eligibility criteria and were assessed in detail. The papers were grouped into 5 thematic categories: 44 physical; 15 art and expressive; 47 psycho-educative; 21 emotionally supportive; and 5 others. Good quality of design was observed in 32 studies, 18 of them uni-dimensional and 14 multi-dimensional. Published randomized controlled studies on cancer rehabilitation are heterogeneous in terms of content and samples, and are mostly characterized by suboptimal design quality. Future studies should be more specific and well-designed with sufficient statistical strength.

An overview of the impact of rare disease characteristics on research methodology.

PubMed

Whicher, Danielle; Philbin, Sarah; Aronson, Naomi

2018-01-19

About 30 million individuals in the United States are living with a rare disease, which by definition have a prevalence of 200,000 or fewer cases in the United States ([National Organization for Rare Disorders], [About NORD], [2016]). Disease heterogeneity and geographic dispersion add to the difficulty of completing robust studies in small populations. Improving the ability to conduct research on rare diseases would have a significant impact on population health. The purpose of this paper is to raise awareness of methodological approaches that can address the challenges to conducting robust research on rare diseases. We conducted a landscape review of available methodological and analytic approaches to address the challenges of rare disease research. Our objectives were to: 1. identify algorithms for matching study design to rare disease attributes and the methodological approaches applicable to these algorithms; 2. draw inferences on how research communities and infrastructure can contribute to the efficiency of research on rare diseases; and 3. to describe methodological approaches in the rare disease portfolio of the Patient-Centered Outcomes Research Institute (PCORI), a funder promoting both rare disease research and research infrastructure. We identified three algorithms for matching study design to rare disease or intervention characteristics (Gagne, et.al, BMJ 349:g6802, 2014); (Gupta, et.al, J Clin Epidemiol 64:1085-1094, 2011); (Cornu, et. al, Orphet J Rare Dis 8:48,2012) and summarized the applicable methodological and analytic approaches. From this literature we were also able to draw inferences on how an effective research infrastructure can set an agenda, prioritize studies, accelerate accrual, catalyze patient engagement and terminate poorly performing studies. Of the 24 rare disease projects in the PCORI portfolio, 11 are randomized controlled trials (RCTs) using standard designs. Thirteen are observational studies using case-control, prospective cohort, or natural history designs. PCORI has supported the development of 9 Patient-Powered Research Networks (PPRNs) focused on rare diseases. Matching research design to attributes of rare diseases and interventions can facilitate the completion of RCTs that are adequately powered. An effective research infrastructure can improve efficiency and avoid waste in rare disease research. Our review of the PCORI research portfolio demonstrates that it is feasible to conduct RCTs in rare disease. However, most of these studies are using standard RCT designs. This suggests that use of a broader array of methodological approaches to RCTs --such as adaptive trials, cross-over trials, and early escape designs can improve the productivity of robust research in rare diseases.

Mechatronics by Analogy and Application to Legged Locomotion

NASA Astrophysics Data System (ADS)

Ragusila, Victor

A new design methodology for mechatronic systems, dubbed as Mechatronics by Analogy (MbA), is introduced and applied to designing a leg mechanism. The new methodology argues that by establishing a similarity relation between a complex system and a number of simpler models it is possible to design the former using the analysis and synthesis means developed for the latter. The methodology provides a framework for concurrent engineering of complex systems while maintaining the transparency of the system behaviour through making formal analogies between the system and those with more tractable dynamics. The application of the MbA methodology to the design of a monopod robot leg, called the Linkage Leg, is also studied. A series of simulations show that the dynamic behaviour of the Linkage Leg is similar to that of a combination of a double pendulum and a spring-loaded inverted pendulum, based on which the system kinematic, dynamic, and control parameters can be designed concurrently. The first stage of Mechatronics by Analogy is a method of extracting significant features of system dynamics through simpler models. The goal is to determine a set of simpler mechanisms with similar dynamic behaviour to that of the original system in various phases of its motion. A modular bond-graph representation of the system is determined, and subsequently simplified using two simplification algorithms. The first algorithm determines the relevant dynamic elements of the system for each phase of motion, and the second algorithm finds the simple mechanism described by the remaining dynamic elements. In addition to greatly simplifying the controller for the system, using simpler mechanisms with similar behaviour provides a greater insight into the dynamics of the system. This is seen in the second stage of the new methodology, which concurrently optimizes the simpler mechanisms together with a control system based on their dynamics. Once the optimal configuration of the simpler system is determined, the original mechanism is optimized such that its dynamic behaviour is analogous. It is shown that, if this analogy is achieved, the control system designed based on the simpler mechanisms can be directly implemented to the more complex system, and their dynamic behaviours are close enough for the system performance to be effectively the same. Finally it is shown that, for the employed objective of fast legged locomotion, the proposed methodology achieves a better design than Reduction-by-Feedback, a competing methodology that uses control layers to simplify the dynamics of the system.

Temporal Code-Driven Stimulation: Definition and Application to Electric Fish Signaling

PubMed Central

Lareo, Angel; Forlim, Caroline G.; Pinto, Reynaldo D.; Varona, Pablo; Rodriguez, Francisco de Borja

2016-01-01

Closed-loop activity-dependent stimulation is a powerful methodology to assess information processing in biological systems. In this context, the development of novel protocols, their implementation in bioinformatics toolboxes and their application to different description levels open up a wide range of possibilities in the study of biological systems. We developed a methodology for studying biological signals representing them as temporal sequences of binary events. A specific sequence of these events (code) is chosen to deliver a predefined stimulation in a closed-loop manner. The response to this code-driven stimulation can be used to characterize the system. This methodology was implemented in a real time toolbox and tested in the context of electric fish signaling. We show that while there are codes that evoke a response that cannot be distinguished from a control recording without stimulation, other codes evoke a characteristic distinct response. We also compare the code-driven response to open-loop stimulation. The discussed experiments validate the proposed methodology and the software toolbox. PMID:27766078

Temporal Code-Driven Stimulation: Definition and Application to Electric Fish Signaling.

PubMed

Lareo, Angel; Forlim, Caroline G; Pinto, Reynaldo D; Varona, Pablo; Rodriguez, Francisco de Borja

2016-01-01

Closed-loop activity-dependent stimulation is a powerful methodology to assess information processing in biological systems. In this context, the development of novel protocols, their implementation in bioinformatics toolboxes and their application to different description levels open up a wide range of possibilities in the study of biological systems. We developed a methodology for studying biological signals representing them as temporal sequences of binary events. A specific sequence of these events (code) is chosen to deliver a predefined stimulation in a closed-loop manner. The response to this code-driven stimulation can be used to characterize the system. This methodology was implemented in a real time toolbox and tested in the context of electric fish signaling. We show that while there are codes that evoke a response that cannot be distinguished from a control recording without stimulation, other codes evoke a characteristic distinct response. We also compare the code-driven response to open-loop stimulation. The discussed experiments validate the proposed methodology and the software toolbox.

Implementing the PAIN RelieveIt Randomized Controlled Trial in Hospice Care: Mechanisms for Success and Meeting PCORI Methodology Standards.

PubMed

Ezenwa, Miriam O; Suarez, Marie L; Carrasco, Jesus D; Hipp, Theresa; Gill, Anayza; Miller, Jacob; Shea, Robert; Shuey, David; Zhao, Zhongsheng; Angulo, Veronica; McCurry, Timothy; Martin, Joanna; Yao, Yingwei; Molokie, Robert E; Wang, Zaijie Jim; Wilkie, Diana J

2017-07-01

This purpose of this article is to describe how we adhere to the Patient-Centered Outcomes Research Institute's (PCORI) methodology standards relevant to the design and implementation of our PCORI-funded study, the PAIN RelieveIt Trial. We present details of the PAIN RelieveIt Trial organized by the PCORI methodology standards and components that are relevant to our study. The PAIN RelieveIt Trial adheres to four PCORI standards and 21 subsumed components. The four standards include standards for formulating research questions, standards associated with patient centeredness, standards for data integrity and rigorous analyses, and standards for preventing and handling missing data. In the past 24 months, we screened 2,837 cancer patients and their caregivers; 874 dyads were eligible; 223.5 dyads consented and provided baseline data. Only 55 patients were lost to follow-up-a 25% attrition rate. The design and implementation of the PAIN RelieveIt Trial adhered to PCORI's methodology standards for research rigor.

Computational Study of Laminar Flow Control on a Subsonic Swept Wing Using Discrete Roughness Elements

NASA Technical Reports Server (NTRS)

Li, Fei; Choudhari, Meelan M.; Chang, Chau-Lyan; Streett, Craig L.; Carpenter, Mark H.

2011-01-01

A combination of parabolized stability equations and secondary instability theory has been applied to a low-speed swept airfoil model with a chord Reynolds number of 7.15 million, with the goals of (i) evaluating this methodology in the context of transition prediction for a known configuration for which roughness based crossflow transition control has been demonstrated under flight conditions and (ii) of analyzing the mechanism of transition delay via the introduction of discrete roughness elements (DRE). Roughness based transition control involves controlled seeding of suitable, subdominant crossflow modes, so as to weaken the growth of naturally occurring, linearly more unstable crossflow modes. Therefore, a synthesis of receptivity, linear and nonlinear growth of stationary crossflow disturbances, and the ensuing development of high frequency secondary instabilities is desirable to understand the experimentally observed transition behavior. With further validation, such higher fidelity prediction methodology could be utilized to assess the potential for crossflow transition control at even higher Reynolds numbers, where experimental data is currently unavailable.

A Response Surface Methodology for Mitigating Hot Gasses in Enclosed Car Park

NASA Astrophysics Data System (ADS)

Faiz Tharima, Ahmad; Zamri Yusoff, Mohd; Mujibur Rahman, Md

2017-12-01

A hot gas rise towards ceiling due to fire buoyancy will cause severe damage to the building structure. The temperature rises need to be controlled as among the elements of compliance in performance-based design. The channel flow between beams has used in this study to mitigate hot gases out of the enclosure by mean of response surface methodology. Fire Dynamic Simulator was employed as a simulation tool while the result was statistically examined using analysis of variance via Minitab application. It was found that the result was linear with predicted R2 (93.25%) and within the permissible R2 (98.13%). The ceiling height has been identified not affect in controlling hot gases while four control parameters which are beam spacing, transversal beam, extraction rate and longitudinal beam with p-values of 0.00, 0.000, 0.023 and 0.000 respectively, have been found to have the significant effect on the smoke temperature control. This study contributes a good input to the fire safety community in providing the initial design of enclosed car park with better condition.

An alternative approach based on artificial neural networks to study controlled drug release.

PubMed

Reis, Marcus A A; Sinisterra, Rubén D; Belchior, Jadson C

2004-02-01

An alternative methodology based on artificial neural networks is proposed to be a complementary tool to other conventional methods to study controlled drug release. Two systems are used to test the approach; namely, hydrocortisone in a biodegradable matrix and rhodium (II) butyrate complexes in a bioceramic matrix. Two well-established mathematical models are used to simulate different release profiles as a function of fundamental properties; namely, diffusion coefficient (D), saturation solubility (C(s)), drug loading (A), and the height of the device (h). The models were tested, and the results show that these fundamental properties can be predicted after learning the experimental or model data for controlled drug release systems. The neural network results obtained after the learning stage can be considered to quantitatively predict ideal experimental conditions. Overall, the proposed methodology was shown to be efficient for ideal experiments, with a relative average error of <1% in both tests. This approach can be useful for the experimental analysis to simulate and design efficient controlled drug-release systems. Copyright 2004 Wiley-Liss, Inc. and the American Pharmacists Association

Network support for turn-taking in multimedia collaboration

NASA Astrophysics Data System (ADS)

Dommel, Hans-Peter; Garcia-Luna-Aceves, Jose J.

1997-01-01

The effectiveness of collaborative multimedia systems depends on the regulation of access to their shared resources, such as continuous media or instruments used concurrently by multiple parties. Existing applications use only simple protocols to mediate such resource contention. Their cooperative rules follow a strict agenda and are largely application-specific. The inherent problem of floor control lacks a systematic methodology. This paper presents a general model on floor control for correct, scalable, fine-grained and fair resource sharing that integrates user interaction with network conditions, and adaptation to various media types. The motion of turn-taking known from psycholinguistics in studies on discourse structure is adapted for this framework. Viewed as a computational analogy to speech communication, online collaboration revolves around dynamically allocated access permissions called floors. The control semantics of floors derives from concurrently control methodology. An explicit specification and verification of a novel distributed Floor Control Protocol are presented. Hosts assume sharing roles that allow for efficient dissemination of control information, agreeing on a floor holder which is granted mutually exclusive access to a resource. Performance analytic aspects of floor control protocols are also briefly discussed.

A systematic review of etiological and risk factors associated with bruxism.

PubMed

Feu, Daniela; Catharino, Fernanda; Quintão, Catia Cardoso Abdo; Almeida, Marco Antonio de Oliveira

2013-06-01

The aim of the present work was to systematically review the literature and identify all peer-reviewed papers dealing with etiological and risk factors associated with bruxism. Data extraction was carried out according to the standard Cochrane systematic review methodology. The following databases were searched for randomized clinical trials (RCT), controlled clinical trials (CCT) or cohort studies: Cochrane Library, Medline, and Embase from 1980 to 2011. Unpublished literature was searched electronically using ClinicalTrials.gov. The primary outcome was bruxism etiology. Studies should have a standardized method to assess bruxism. Screening of eligible studies, assessment of the methodological quality and data extraction were conducted independently and in duplicate. Two reviewers inspected the references using the same search strategy and then applied the same inclusion criteria to the selected studies. They used criteria for methodological quality that was previously described in the Cochrane Handbook. Among the 1247 related articles that were critically assessed, one randomized clinical trial, one controlled clinical trial and seven longitudinal studies were included in the critical appraisal. Of these studies, five were selected, but reported different outcomes. There is convincing evidence that (sleep-related) bruxism can be induced by esophageal acidification and also that it has an important relationship with smoking in a dose-dependent manner. Disturbances in the central dopaminergic system are also implicated in the etiology of bruxism.

Quasi-experimental study designs series-paper 9: collecting data from quasi-experimental studies.

PubMed

Aloe, Ariel M; Becker, Betsy Jane; Duvendack, Maren; Valentine, Jeffrey C; Shemilt, Ian; Waddington, Hugh

2017-09-01

To identify variables that must be coded when synthesizing primary studies that use quasi-experimental designs. All quasi-experimental (QE) designs. When designing a systematic review of QE studies, potential sources of heterogeneity-both theory-based and methodological-must be identified. We outline key components of inclusion criteria for syntheses of quasi-experimental studies. We provide recommendations for coding content-relevant and methodological variables and outlined the distinction between bivariate effect sizes and partial (i.e., adjusted) effect sizes. Designs used and controls used are viewed as of greatest importance. Potential sources of bias and confounding are also addressed. Careful consideration must be given to inclusion criteria and the coding of theoretical and methodological variables during the design phase of a synthesis of quasi-experimental studies. The success of the meta-regression analysis relies on the data available to the meta-analyst. Omission of critical moderator variables (i.e., effect modifiers) will undermine the conclusions of a meta-analysis. Copyright © 2017 Elsevier Inc. All rights reserved.

An example of requirements for Advanced Subsonic Civil Transport (ASCT) flight control system using structured techniques

NASA Technical Reports Server (NTRS)

Mclees, Robert E.; Cohen, Gerald C.

1991-01-01

The requirements are presented for an Advanced Subsonic Civil Transport (ASCT) flight control system generated using structured techniques. The requirements definition starts from initially performing a mission analysis to identify the high level control system requirements and functions necessary to satisfy the mission flight. The result of the study is an example set of control system requirements partially represented using a derivative of Yourdon's structured techniques. Also provided is a research focus for studying structured design methodologies and in particular design-for-validation philosophies.

Fuzzy Current-Mode Control and Stability Analysis

NASA Technical Reports Server (NTRS)

Kopasakis, George

2000-01-01

In this paper a current-mode control (CMC) methodology is developed for a buck converter by using a fuzzy logic controller. Conventional CMC methodologies are based on lead-lag compensation with voltage and inductor current feedback. In this paper the converter lead-lag compensation will be substituted with a fuzzy controller. A small-signal model of the fuzzy controller will also be developed in order to examine the stability properties of this buck converter control system. The paper develops an analytical approach, introducing fuzzy control into the area of CMC.

Coping with Pain in the Motivational Context of Values: Comparison between an Acceptance-Based and a Cognitive Control-Based Protocol

ERIC Educational Resources Information Center

Paez-Blarrina, Marisa; Luciano, Carmen; Gutierrez-Martinez, Olga; Valdivia, Sonsoles; Rodriguez-Valverde, Miguel; Ortega, Jose

2008-01-01

This study compares the effect of an acceptance-based protocol (ACT) and a cognitive control-based (CONT) protocol on three measures of pain coping: tolerance, self-report, and believability. Specific methodological controls were employed to further isolate the role of the value of participating in a pain task, compared to previous investigations…

Landslide hazard analysis for pipelines: The case of the Simonette river crossing

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

Grivas, D.A.; Schultz, B.C.; O`Neil, G.

1995-12-31

The overall objective of this study is to develop a probabilistic methodology to analyze landslide hazards and their effects on the safety of buried pipelines. The methodology incorporates a range of models that can accommodate differences in the ground movement modes and the amount and type of information available at various site locations. Two movement modes are considered, namely (a) instantaneous (catastrophic) slides, and (b) gradual ground movement which may result in cumulative displacements over the pipeline design life (30--40 years) that are in excess of allowable values. Probabilistic analysis is applied in each case to address the uncertainties associatedmore » with important factors that control slope stability. Availability of information ranges from relatively well studied, instrumented installations to cases where data is limited to what can be derived from topographic and geologic maps. The methodology distinguishes between procedures applied where there is little information and those that can be used when relatively extensive data is available. important aspects of the methodology are illustrated in a case study involving a pipeline located in Northern Alberta, Canada, in the Simonette river valley.« less

Progress Report for the Robotic Intelligence Evaluation. Program Year 1: Developing Test Methodology for Anti-Rollover Systems

DTIC Science & Technology

2006-06-01

Scientific Research. 5PAM-Crash is a trademark of the ESI Group . 6MATLAB and SIMULINK are registered trademarks of the MathWorks. 14 maneuvers...Laboratory (ARL) to develop methodologies to evaluate robotic behavior algorithms that control the actions of individual robots or groups of robots...methodologies to evaluate robotic behavior algorithms that control the actions of individual robots or groups of robots acting as a team to perform a

The effects of mental practice in neurological rehabilitation; a systematic review and meta-analysis

PubMed Central

Braun, Susy; Kleynen, Melanie; van Heel, Tessa; Kruithof, Nena; Wade, Derick; Beurskens, Anna

2013-01-01

Objective: To investigate the beneficial and adverse effects of a mental practice intervention on activities, cognition, and emotion in patients after stroke, patients with Parkinson's disease or multiple sclerosis. Methods: Electronic databases PubMed/Medline, PEDro, Science Direct, Cochrane Library, PsycINFO, Rehadat, Embase, and Picarta were searched until June 2012. Fourteen randomized controlled trials in stroke and two randomized controlled trials in Parkinson's disease were included, representing 491 patients (421 with stroke). No randomized controlled trials in multiple sclerosis were identified. The methodologic quality of the included trials was assessed with the Amsterdam-Maastricht-Consensus-List (AMCL). Information on study characteristics and outcomes was summarized and evidence for effects described. Data from individual studies in stroke with same outcome measures were pooled. Results: The included 16 randomized controlled trials were heterogeneous and methodologic quality varied. Ten trials reported significant effects in favor of mental practice in patients with stroke (n = 9) and Parkinson's disease (n = 1). In six studies mental practice had similar effects as therapy as usual (n = 5 in stroke and n = 1 in Parkinson's disease). Of six performed meta-analyses with identical measures in stroke studies only two showed significant effects of mental practice: short-term improvement of arm-hand-ability (ARAT: SMD 0.62; 95% CI: 0.05 to 1.19) and improvement of performance of activities (NRS: SMD 0.9; 95% CI: 0.04 to 1.77). Five studies found effects on cognition (e.g., effects on attention, plan actions in unfamiliar surroundings) and four reported observed side-effects, both positive (e.g., might increase motivation and arousal and reduce depression) and negative (e.g., diminished concentration, irritation). Conclusions: Mental practice might have positive effects on performance of activities in patients with neurological diseases, but this review reports less positive results than earlier published ones. Strengths and limitations of past studies are pointed out. Methodologic recommendations for future studies are given. PMID:23935572

Modeling Negotiation by a Paticipatory Approach

NASA Astrophysics Data System (ADS)

Torii, Daisuke; Ishida, Toru; Bousquet, François

In a participatory approach by social scientists, role playing games (RPG) are effectively used to understand real thinking and behavior of stakeholders, but RPG is not sufficient to handle a dynamic process like negotiation. In this study, a participatory simulation where user-controlled avatars and autonomous agents coexist is introduced to the participatory approach for modeling negotiation. To establish a modeling methodology of negotiation, we have tackled the following two issues. First, for enabling domain experts to concentrate interaction design for participatory simulation, we have adopted the architecture in which an interaction layer controls agents and have defined three types of interaction descriptions (interaction protocol, interaction scenario and avatar control scenario) to be described. Second, for enabling domain experts and stakeholders to capitalize on participatory simulation, we have established a four-step process for acquiring negotiation model: 1) surveys and interviews to stakeholders, 2) RPG, 3) interaction design, and 4) participatory simulation. Finally, we discussed our methodology through a case study of agricultural economics in the northeast Thailand.

A toolbox to explore the mechanics of living embryonic tissues

PubMed Central

Campàs, Otger

2016-01-01

The sculpting of embryonic tissues and organs into their functional morphologies involves the spatial and temporal regulation of mechanics at cell and tissue scales. Decades of in vitro work, complemented by some in vivo studies, have shown the relevance of mechanical cues in the control of cell behaviors that are central to developmental processes, but the lack of methodologies enabling precise, quantitative measurements of mechanical cues in vivo have hindered our understanding of the role of mechanics in embryonic development. Several methodologies are starting to enable quantitative studies of mechanics in vivo and in situ, opening new avenues to explore how mechanics contributes to shaping embryonic tissues and how it affects cell behavior within developing embryos. Here we review the present methodologies to study the role of mechanics in living embryonic tissues, considering their strengths and drawbacks as well as the conditions in which they are most suitable. PMID:27061360

A toolbox to explore the mechanics of living embryonic tissues.

PubMed

Campàs, Otger

2016-07-01

The sculpting of embryonic tissues and organs into their functional morphologies involves the spatial and temporal regulation of mechanics at cell and tissue scales. Decades of in vitro work, complemented by some in vivo studies, have shown the relevance of mechanical cues in the control of cell behaviors that are central to developmental processes, but the lack of methodologies enabling precise, quantitative measurements of mechanical cues in vivo have hindered our understanding of the role of mechanics in embryonic development. Several methodologies are starting to enable quantitative studies of mechanics in vivo and in situ, opening new avenues to explore how mechanics contributes to shaping embryonic tissues and how it affects cell behavior within developing embryos. Here we review the present methodologies to study the role of mechanics in living embryonic tissues, considering their strengths and drawbacks as well as the conditions in which they are most suitable. Copyright © 2016 Elsevier Ltd. All rights reserved.

A methodology for calculating transport emissions in cities with limited traffic data: Case study of diesel particulates and black carbon emissions in Murmansk.

PubMed

Kholod, N; Evans, M; Gusev, E; Yu, S; Malyshev, V; Tretyakova, S; Barinov, A

2016-03-15

This paper presents a methodology for calculating exhaust emissions from on-road transport in cities with low-quality traffic data and outdated vehicle registries. The methodology consists of data collection approaches and emission calculation methods. For data collection, the paper suggests using video survey and parking lot survey methods developed for the International Vehicular Emissions model. Additional sources of information include data from the largest transportation companies, vehicle inspection stations, and official vehicle registries. The paper suggests using the European Computer Programme to Calculate Emissions from Road Transport (COPERT) 4 model to calculate emissions, especially in countries that implemented European emissions standards. If available, the local emission factors should be used instead of the default COPERT emission factors. The paper also suggests additional steps in the methodology to calculate emissions only from diesel vehicles. We applied this methodology to calculate black carbon emissions from diesel on-road vehicles in Murmansk, Russia. The results from Murmansk show that diesel vehicles emitted 11.7 tons of black carbon in 2014. The main factors determining the level of emissions are the structure of the vehicle fleet and the level of vehicle emission controls. Vehicles without controls emit about 55% of black carbon emissions. Copyright © 2015 Elsevier B.V. All rights reserved.

Embedded control system for computerized franking machine

NASA Astrophysics Data System (ADS)

Shi, W. M.; Zhang, L. B.; Xu, F.; Zhan, H. W.

2007-12-01

This paper presents a novel control system for franking machine. A methodology for operating a franking machine using the functional controls consisting of connection, configuration and franking electromechanical drive is studied. A set of enabling technologies to synthesize postage management software architectures driven microprocessor-based embedded systems is proposed. The cryptographic algorithm that calculates mail items is analyzed to enhance the postal indicia accountability and security. The study indicated that the franking machine is reliability, performance and flexibility in printing mail items.

Model identification and vision-based H∞ position control of 6-DoF cable-driven parallel robots

NASA Astrophysics Data System (ADS)

Chellal, R.; Cuvillon, L.; Laroche, E.

2017-04-01

This paper presents methodologies for the identification and control of 6-degrees of freedom (6-DoF) cable-driven parallel robots (CDPRs). First a two-step identification methodology is proposed to accurately estimate the kinematic parameters independently and prior to the dynamic parameters of a physics-based model of CDPRs. Second, an original control scheme is developed, including a vision-based position controller tuned with the H∞ methodology and a cable tension distribution algorithm. The position is controlled in the operational space, making use of the end-effector pose measured by a motion-tracking system. A four-block H∞ design scheme with adjusted weighting filters ensures good trajectory tracking and disturbance rejection properties for the CDPR system, which is a nonlinear-coupled MIMO system with constrained states. The tension management algorithm generates control signals that maintain the cables under feasible tensions. The paper makes an extensive review of the available methods and presents an extension of one of them. The presented methodologies are evaluated by simulations and experimentally on a redundant 6-DoF INCA 6D CDPR with eight cables, equipped with a motion-tracking system.

Behavior Analysis: Methodological Foundations.

ERIC Educational Resources Information Center

Owen, James L.

Behavior analysis provides a unique way of coming to understand intrapersonal and interpersonal communication behaviors, and focuses on control techniques available to a speaker and counter-control techniques available to a listener. "Time-series methodology" is a convenient term because it subsumes under one label a variety of baseline…

Brake testing methodology study : driver effects testing

DOT National Transportation Integrated Search

1999-03-01

The National Highway Traffic Safety Administration (NHTSA) is exploring the feasibility of developing brake tests to measure brake system performance of light vehicles. Developing test procedures requires controlling test variability so that measured...

[Methodological quality of an article on the treatment of gastric cancer adopted as protocol by some Chilean hospitals].

PubMed

Manterola, Carlos; Torres, Rodrigo; Burgos, Luis; Vial, Manuel; Pineda, Viviana

2006-07-01

Surgery is a curative treatment for gastric cancer (GC). As relapse is frequent, adjuvant therapies such as postoperative chemo radiotherapy have been tried. In Chile, some hospitals adopted Macdonald's study as a protocol for the treatment of GC. To determine methodological quality and internal and external validity of the Macdonald study. Three instruments were applied that assess methodological quality. A critical appraisal was done and the internal and external validity of the methodological quality was analyzed with two scales: MINCIR (Methodology and Research in Surgery), valid for therapy studies and CONSORT (Consolidated Standards of Reporting Trials), valid for randomized controlled trials (RCT). Guides and scales were applied by 5 researchers with training in clinical epidemiology. The reader's guide verified that the Macdonald study was not directed to answer a clearly defined question. There was random assignment, but the method used is not described and the patients were not considered until the end of the study (36% of the group with surgery plus chemo radiotherapy did not complete treatment). MINCIR scale confirmed a multicentric RCT, not blinded, with an unclear randomized sequence, erroneous sample size estimation, vague objectives and no exclusion criteria. CONSORT system proved the lack of working hypothesis and specific objectives as well as an absence of exclusion criteria and identification of the primary variable, an imprecise estimation of sample size, ambiguities in the randomization process, no blinding, an absence of statistical adjustment and the omission of a subgroup analysis. The instruments applied demonstrated methodological shortcomings that compromise the internal and external validity of the.

Can teaching research methodology influence students' attitude toward science? Cohort study and nonrandomized trial in a single medical school.

PubMed

Vujaklija, Ana; Hren, Darko; Sambunjak, Dario; Vodopivec, Ivana; Ivanis, Ana; Marusić, Ana; Marusić, Matko

2010-02-01

Medical teaching aims to develop attitudes and behaviors underlying professional competence of future physicians. We investigated whether a mandatory course on scientific methodology in the second study year could affect students' attitudes toward science in medicine. In a longitudinal study, students (n = 241) enrolling in 2001-2002 academic year at a single medical school were followed up until graduation in 2006-2007. Each year, they filled out a Likert-type questionnaire of 18 statements evaluating attitude toward science. Direct influence of the course on students' attitudes was tested in a nonrandomized controlled trial with the 2006-2007 second year student cohort. Positive students' attitudes toward science increased during study years (mean [SD] score of the maximum score of 90): from 57.6 (6.0) in the first to 69.8 (10.4) in the sixth year. There was a significant trend of increase in attitudes with the years of study (cubic trend by polynomial contrasts analysis, P = 0.011). Attendance of a course on research methodology significantly increased positive attitudes (score, 67.0 [7.0] before and 70.8 [7.5] after course, P = 0.032 vs control group), regardless of grade point average. The intervention had an effect even when the influence of the initial attitude was accounted for (F1,140 = 9.25, P = 0.003; analysis of covariance). The attitude changes after the course was greatest in students with low initial attitude scores (Spearman rinitial score, score difference, -0.44). Medical students have positive attitudes toward science and scientific method in medicine. Attendance of a course on research methodology had positive short-term effect on students' attitudes toward science. This positive effect should be maintained by vertical integration of the course in the medical curriculum.

Development of a Tailored Methodology and Forensic Toolkit for Industrial Control Systems Incident Response

DTIC Science & Technology

2014-06-01

for industrial control systems ,” in Proceedings of the VDE Kongress, 2004. [15] K. Stouffer et al., “Special publication 800-82: Guide to industrial...TAILORED METHODOLOGY AND FORENSIC TOOLKIT FOR INDUSTRIAL CONTROL SYSTEMS INCIDENT RESPONSE by Nicholas B. Carr June 2014 Thesis Co...CONTROL SYSTEMS INCIDENT RESPONSE 5. FUNDING NUMBERS 6. AUTHOR(S) Nicholas B. Carr 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Naval

Measurement control workshop instructional materials

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

Gibbs, Philip; Harvel, Charles; Clark, John

2012-09-01

An essential element in an effective nuclear materials control and accountability (MC&A) program is the measurement of the nuclear material as it is received, moved, processed and shipped. Quality measurement systems and methodologies determine the accuracy of the accountability values. Implementation of a measurement control program is essential to ensure that the measurement systems and methodologies perform as expected. A measurement control program also allows for a determination of the level of confidence in the accounting values.

The Researching on Evaluation of Automatic Voltage Control Based on Improved Zoning Methodology

NASA Astrophysics Data System (ADS)

Xiao-jun, ZHU; Ang, FU; Guang-de, DONG; Rui-miao, WANG; De-fen, ZHU

2018-03-01

According to the present serious phenomenon of increasing size and structure of power system, hierarchically structured automatic voltage control(AVC) has been the researching spot. In the paper, the reduced control model is built and the adaptive reduced control model is researched to improve the voltage control effect. The theories of HCSD, HCVS, SKC and FCM are introduced and the effect on coordinated voltage regulation caused by different zoning methodologies is also researched. The generic framework for evaluating performance of coordinated voltage regulation is built. Finally, the IEEE-96 stsyem is used to divide the network. The 2383-bus Polish system is built to verify that the selection of a zoning methodology affects not only the coordinated voltage regulation operation, but also its robustness to erroneous data and proposes a comprehensive generic framework for evaluating its performance. The New England 39-bus network is used to verify the adaptive reduced control models’ performance.

Fuzzy logic controllers for electrotechnical devices - On-site tuning approach

NASA Astrophysics Data System (ADS)

Hissel, D.; Maussion, P.; Faucher, J.

2001-12-01

Fuzzy logic offers nowadays an interesting alternative to the designers of non linear control laws for electrical or electromechanical systems. However, due to the huge number of tuning parameters, this kind of control is only used in a few industrial applications. This paper proposes a new, very simple, on-site tuning strategy for a PID-like fuzzy logic controller. Thanks to the experimental designs methodology, we will propose sets of optimized pre-established settings for this kind of fuzzy controllers. The proposed parameters are only depending on one on-site open-loop identification test. In this way, this on-site tuning methodology has to be compared to the Ziegler-Nichols one's for conventional controllers. Experimental results (on a permanent magnets synchronous motor and on a DC/DC converter) will underline all the efficiency of this tuning methodology. Finally, the field of validity of the proposed pre-established settings will be given.

Space Station man-machine automation trade-off analysis

NASA Technical Reports Server (NTRS)

Zimmerman, W. F.; Bard, J.; Feinberg, A.

1985-01-01

The man machine automation tradeoff methodology presented is of four research tasks comprising the autonomous spacecraft system technology (ASST) project. ASST was established to identify and study system level design problems for autonomous spacecraft. Using the Space Station as an example spacecraft system requiring a certain level of autonomous control, a system level, man machine automation tradeoff methodology is presented that: (1) optimizes man machine mixes for different ground and on orbit crew functions subject to cost, safety, weight, power, and reliability constraints, and (2) plots the best incorporation plan for new, emerging technologies by weighing cost, relative availability, reliability, safety, importance to out year missions, and ease of retrofit. A fairly straightforward approach is taken by the methodology to valuing human productivity, it is still sensitive to the important subtleties associated with designing a well integrated, man machine system. These subtleties include considerations such as crew preference to retain certain spacecraft control functions; or valuing human integration/decision capabilities over equivalent hardware/software where appropriate.

Systematic Review of Integrative Health Care Research: Randomized Control Trials, Clinical Controlled Trials, and Meta-Analysis

PubMed Central

Khorsan, Raheleh; Coulter, Ian D.; Crawford, Cindy; Hsiao, An-Fu

2011-01-01

A systematic review was conducted to assess the level of evidence for integrative health care research. We searched PubMed, Allied and Complementary Medicine (AMED), BIOSIS Previews, EMBASE, the entire Cochrane Library, MANTIS, Social SciSearch, SciSearch Cited Ref Sci, PsychInfo, CINAHL, and NCCAM grantee publications listings, from database inception to May 2009, as well as searches of the “gray literature.” Available studies published in English language were included. Three independent reviewers rated each article and assessed the methodological quality of studies using the Scottish Intercollegiate Guidelines Network (SIGN 50). Our search yielded 11,891 total citations but 6 clinical studies, including 4 randomized, met our inclusion criteria. There are no available systematic reviews/meta-analyses published that met our inclusion criteria. The methodological quality of the included studies was assessed independently using quality checklists of the SIGN 50. Only a small number of RCTs and CCTs with a limited number of patients and lack of adequate control groups assessing integrative health care research are available. These studies provide limited evidence of effective integrative health care on some modalities. However, integrative health care regimen appears to be generally safe. PMID:20953383

Guidelines for the Design and Conduct of Clinical Studies in Knee Articular Cartilage Repair

PubMed Central

Mithoefer, Kai; Saris, Daniel B.F.; Farr, Jack; Kon, Elizaveta; Zaslav, Kenneth; Cole, Brian J.; Ranstam, Jonas; Yao, Jian; Shive, Matthew; Levine, David; Dalemans, Wilfried; Brittberg, Mats

2011-01-01

Objective: To summarize current clinical research practice and develop methodological standards for objective scientific evaluation of knee cartilage repair procedures and products. Design: A comprehensive literature review was performed of high-level original studies providing information relevant for the design of clinical studies on articular cartilage repair in the knee. Analysis of cartilage repair publications and synopses of ongoing trials were used to identify important criteria for the design, reporting, and interpretation of studies in this field. Results: Current literature reflects the methodological limitations of the scientific evidence available for articular cartilage repair. However, clinical trial databases of ongoing trials document a trend suggesting improved study designs and clinical evaluation methodology. Based on the current scientific information and standards of clinical care, detailed methodological recommendations were developed for the statistical study design, patient recruitment, control group considerations, study endpoint definition, documentation of results, use of validated patient-reported outcome instruments, and inclusion and exclusion criteria for the design and conduct of scientifically sound cartilage repair study protocols. A consensus statement among the International Cartilage Repair Society (ICRS) and contributing authors experienced in clinical trial design and implementation was achieved. Conclusions: High-quality clinical research methodology is critical for the optimal evaluation of current and new cartilage repair technologies. In addition to generally applicable principles for orthopedic study design, specific criteria and considerations apply to cartilage repair studies. Systematic application of these criteria and considerations can facilitate study designs that are scientifically rigorous, ethical, practical, and appropriate for the question(s) being addressed in any given cartilage repair research project. PMID:26069574

Risk of bias and methodological issues in randomised controlled trials of acupuncture for knee osteoarthritis: a cross-sectional study

PubMed Central

Lee, Andy H; Zhou, Xu; Kang, Deying; Luo, Yanan; Liu, Jiali; Sun, Xin

2018-01-01

Objective To assess risk of bias and to investigate methodological issues concerning the design, conduct and analysis of randomised controlled trials (RCTs) testing acupuncture for knee osteoarthritis (KOA). Methods PubMed, EMBASE, Cochrane Central Register of Controlled Trials and four major Chinese databases were searched for RCTs that investigated the effect of acupuncture for KOA. The Cochrane tool was used to examine the risk of bias of eligible RCTs. Their methodological details were examined using a standardised and pilot-tested questionnaire of 48 items, together with the association between four predefined factors and important methodological quality indicators. Results A total of 248 RCTs were eligible, of which 39 (15.7%) used computer-generated randomisation sequence. Of the 31 (12.5%) trials that stated the allocation concealment, only one used central randomisation. Twenty-five (10.1%) trials mentioned that their acupuncture procedures were standardised, but only 18 (7.3%) specified how the standardisation was achieved. The great majority of trials (n=233, 94%) stated that blinding was in place, but 204 (87.6%) did not clarify who was blinded. Only 27 (10.9%) trials specified the primary outcome, for which 7 used intention-to-treat analysis. Only 17 (6.9%) trials included details on sample size calculation; none preplanned an interim analysis and associated stopping rule. In total, 46 (18.5%) trials explicitly stated that loss to follow-up occurred, but only 6 (2.4%) provided some information to deal with the issue. No trials prespecified, conducted or reported any subgroup or adjusted analysis for the primary outcome. Conclusion The overall risk of bias was high among published RCTs testing acupuncture for KOA. Methodological limitations were present in many important aspects of design, conduct and analyses. These findings inform the development of evidence-based methodological guidance for future trials assessing the effect of acupuncture for KOA. PMID:29511016

Analytical and simulator study of advanced transport

NASA Technical Reports Server (NTRS)

Levison, W. H.; Rickard, W. W.

1982-01-01

An analytic methodology, based on the optimal-control pilot model, was demonstrated for assessing longitidunal-axis handling qualities of transport aircraft in final approach. Calibration of the methodology is largely in terms of closed-loop performance requirements, rather than specific vehicle response characteristics, and is based on a combination of published criteria, pilot preferences, physical limitations, and engineering judgment. Six longitudinal-axis approach configurations were studied covering a range of handling qualities problems, including the presence of flexible aircraft modes. The analytical procedure was used to obtain predictions of Cooper-Harper ratings, a solar quadratic performance index, and rms excursions of important system variables.

CRITICAL REVIEW OF OUTCOME RESEARCH ON INTERPERSONAL PSYCHOTHERAPY FOR ANXIETY DISORDERS

PubMed Central

Markowitz, John C.; Lipsitz, Joshua; Milrod, Barbara L.

2014-01-01

Background Interpersonal psychotherapy (IPT) has demonstrated efficacy in treating mood and eating disorders. This article critically reviews outcome research testing IPT for anxiety disorders, a diagnostic area where cognitive behavioral therapy (CBT) has dominated research and treatment. Methods A literature search identified six open and five controlled trials of IPT for social anxiety disorder (SAD), panic disorder, and posttraumatic stress disorder. Results Studies were generally small, underpowered, and sometimes methodologically compromised. Nonetheless, minimally adapted from its standard depression strategies, IPT for anxiety disorders yielded positive results in open trials for the three diagnoses. In controlled trials, IPT fared better than waiting list (N = 2), was equipotent to supportive psychodynamic psychotherapy (N = 1), but less efficacious than CBT for SAD (N = 1), and CBT for panic disorder (N = 1) in a methodologically complicated study. IPT equaled CBT in a group residential format (N = 1). Conclusions IPT shows some promise for anxiety disorders but has thus far shown no advantages in controlled trials relative to other therapies. Methodological and ecological issues have complicated testing of IPT for anxiety disorders, clouding some findings. The authors discuss difficulties of conducting non-CBT research in a CBT-dominated area, investigator bias, and the probable need to further modify IPT for anxiety disorders. Untested therapies deserve the fairest possible testing. Depression and Anxiety 00:1–10, 2014. PMID:24493661

Application of Six Sigma/CAP methodology: controlling blood-product utilization and costs.

PubMed

Neri, Robert A; Mason, Cindy E; Demko, Lisa A

2008-01-01

Blood-product components are a limited commodity whose cost is rising. Many patients benefit from their use, but patients who receive transfusions face an unnecessary increased risk for developing infections; fatal, febrile, or allergic reactions; and circulatory overload. To improve patient care, safety, and resource stewardship, transfusion practices must be evaluated for appropriateness (Wilson et al. 2002). A multihospital health system undertook a rigorous study of blood-product utilization patterns and management processes to address cost-control problems in the organization. The system leveraged two process improvement tools widely implemented outside of the healthcare industry: (1) Six Sigma methodology to identify blood-utilization drivers and to standardize transfusion practice, and (2) change acceleration process model to drive effective change. The initiative resulted in a decreased rate of inappropriate transfusions of packed red blood cell from 16 percent to less than 5 percent, improved clinician use of a blood-component order form, establishment of internal benchmarks, enhanced laboratory-to-clinician communication, and better blood-product expense control. The project further demonstrated how out-of-industry tools and methodologies can be adopted, adapted, and systematically applied to generate positive change (Black and Revere 2006).

Harmonizing Automatic Test System Assets, Drivers, and Control Methodologies

DTIC Science & Technology

1999-07-18

ORGANIZATION PRINCIPAL AREAS OF INTEREST TO ATS NAME 1394 TA Firewire Trade Association Defining high speed bus protocol Active Group Accelerating ActiveX ...System Assets, Drivers, and Control Methodologies 17 JUL, 1999 component is a diagonal matrix containing scaling values such that when the three

A Control Law Design Method Facilitating Control Power, Robustness, Agility, and Flying Qualities Tradeoffs: CRAFT

NASA Technical Reports Server (NTRS)

Murphy, Patrick C.; Davidson, John B.

1998-01-01

A multi-input, multi-output control law design methodology, named "CRAFT", is presented. CRAFT stands for the design objectives addressed, namely, Control power, Robustness, Agility, and Flying Qualities Tradeoffs. The methodology makes use of control law design metrics from each of the four design objective areas. It combines eigenspace assignment, which allows for direct specification of eigenvalues and eigenvectors, with a graphical approach for representing the metrics that captures numerous design goals in one composite illustration. Sensitivity of the metrics to eigenspace choice is clearly displayed, enabling the designer to assess the cost of design tradeoffs. This approach enhances the designer's ability to make informed design tradeoffs and to reach effective final designs. An example of the CRAFT methodology applied to an advanced experimental fighter and discussion of associated design issues are provided.

Methods for a study of Anticipatory and Preventive multidisciplinary Team Care in a family practice.

PubMed

Dahrouge, Simone; Hogg, William; Lemelin, Jacques; Liddy, Clare; Legault, Frances

2010-02-01

BACKGROUND T o examine the methodology used to evaluate whether focusing the work of nurse practitioners and a pharmacist on frail and at-risk patients would improve the quality of care for such patients. Evaluation of methodology of a randomized controlled trial including analysis of quantitative and qualitative data over time and analysis of cost-effectiveness. A single practice in a rural area near Ottawa, Ont. A total of 241 frail patients, aged 50 years and older, at risk of experiencing adverse health outcomes. At-risk patients were randomly assigned to receive Anticipatory and Preventive Team Care (from their family physicians, 1 of 3 nurse practitioners, and a pharmacist) or usual care. The principal outcome for the study was the quality of care for chronic disease management. Secondary outcomes included other quality of care measures and evaluation of the program process and its cost-effectiveness. This article examines the effectiveness of the methodology used. Quantitative data from surveys, administrative databases, and medical records were supplemented with qualitative information from interviews, focus groups, work logs, and study notes. Three factors limit our ability to fully demonstrate the potential effects of this team structure. For reasons outside our control, the intervention duration was shorter than intended; the practice's physical layout did not facilitate interactions between the care providers; and contamination of the intervention effect into the control arm cannot be excluded. The study used a randomized design, relied on a multifaceted approach to evaluating its effects, and used several sources of data. TRIAL REGISTRATION NUMBER NCT00238836 (CONSORT).

A Study of the Critical Factors Controlling the Synthesis of Ceramic Matrix Composites from Preceramic Polymers.

DTIC Science & Technology

1988-04-15

physical properties of a polycarbosilane preceramic polymer as a function of temperature to derive synthesis methodology for SiC matrix composites , (2...investigate the role of interface modification in creating tough carbon fiber reinforced SiC matrix composites . RESEARCH PROGRESS Preceramic Polymer ...Classfication) A STUDY OF THE CRITICAL FACTORS CONTROLLING THE SYNTHESIS OF CERAMIC MATRIX COMPOSITES FROM PRECERAMIC POLYMERS 12. PERSONAL AUTHOR(S

An Overview of Meta-Analyses of Danhong Injection for Unstable Angina.

PubMed

Zhang, Xiaoxia; Wang, Hui; Chang, Yanxu; Wang, Yuefei; Lei, Xiang; Fu, Shufei; Zhang, Junhua

2015-01-01

Objective. To systematically collect evidence and evaluate the effects of Danhong injection (DHI) for unstable angina (UA). Methods. A comprehensive search was conducted in seven electronic databases up to January 2015. The methodological and reporting quality of included studies was assessed by using AMSTAR and PRISMA. Result. Five articles were included. The conclusions suggest that DHI plus conventional medicine treatment was effective for UA pectoris treatment, could alleviate symptoms of angina and ameliorate electrocardiograms. Flaws of the original studies and systematic reviews weaken the strength of evidence. Limitations of the methodology quality include performing an incomprehensive literature search, lacking detailed characteristics, ignoring clinical heterogeneity, and not assessing publication bias and other forms of bias. The flaws of reporting systematic reviews included the following: not providing a structured summary, no standardized search strategy. For the pooled findings, researchers took statistical heterogeneity into consideration, but clinical and methodology heterogeneity were ignored. Conclusion. DHI plus conventional medicine treatment generally appears to be effective for UA treatment. However, the evidence is not hard enough due to methodological flaws in original clinical trials and systematic reviews. Furthermore, rigorous designed randomized controlled trials are also needed. The methodology and reporting quality of systematic reviews should be improved.

An Overview of Meta-Analyses of Danhong Injection for Unstable Angina

PubMed Central

Zhang, Xiaoxia; Chang, Yanxu; Wang, Yuefei; Lei, Xiang; Fu, Shufei; Zhang, Junhua

2015-01-01

Objective. To systematically collect evidence and evaluate the effects of Danhong injection (DHI) for unstable angina (UA). Methods. A comprehensive search was conducted in seven electronic databases up to January 2015. The methodological and reporting quality of included studies was assessed by using AMSTAR and PRISMA. Result. Five articles were included. The conclusions suggest that DHI plus conventional medicine treatment was effective for UA pectoris treatment, could alleviate symptoms of angina and ameliorate electrocardiograms. Flaws of the original studies and systematic reviews weaken the strength of evidence. Limitations of the methodology quality include performing an incomprehensive literature search, lacking detailed characteristics, ignoring clinical heterogeneity, and not assessing publication bias and other forms of bias. The flaws of reporting systematic reviews included the following: not providing a structured summary, no standardized search strategy. For the pooled findings, researchers took statistical heterogeneity into consideration, but clinical and methodology heterogeneity were ignored. Conclusion. DHI plus conventional medicine treatment generally appears to be effective for UA treatment. However, the evidence is not hard enough due to methodological flaws in original clinical trials and systematic reviews. Furthermore, rigorous designed randomized controlled trials are also needed. The methodology and reporting quality of systematic reviews should be improved. PMID:26539221

The use of experimental design to find the operating maximum power point of PEM fuel cells

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

Crăciunescu, Aurelian; Pătularu, Laurenţiu; Ciumbulea, Gloria

2015-03-10

Proton Exchange Membrane (PEM) Fuel Cells are difficult to model due to their complex nonlinear nature. In this paper, the development of a PEM Fuel Cells mathematical model based on the Design of Experiment methodology is described. The Design of Experiment provides a very efficient methodology to obtain a mathematical model for the studied multivariable system with only a few experiments. The obtained results can be used for optimization and control of the PEM Fuel Cells systems.

Population-Level Cost-Effectiveness of Implementing Evidence-Based Practices into Routine Care

PubMed Central

Fortney, John C; Pyne, Jeffrey M; Burgess, James F

2014-01-01

Objective The objective of this research was to apply a new methodology (population-level cost-effectiveness analysis) to determine the value of implementing an evidence-based practice in routine care. Data Sources/Study Setting Data are from sequentially conducted studies: a randomized controlled trial and an implementation trial of collaborative care for depression. Both trials were conducted in the same practice setting and population (primary care patients prescribed antidepressants). Study Design The study combined results from a randomized controlled trial and a pre-post-quasi-experimental implementation trial. Data Collection/Extraction Methods The randomized controlled trial collected quality-adjusted life years (QALYs) from survey and medication possession ratios (MPRs) from administrative data. The implementation trial collected MPRs and intervention costs from administrative data and implementation costs from survey. Principal Findings In the randomized controlled trial, MPRs were significantly correlated with QALYs (p = .03). In the implementation trial, patients at implementation sites had significantly higher MPRs (p = .01) than patients at control sites, and by extrapolation higher QALYs (0.00188). Total costs (implementation, intervention) were nonsignificantly higher ($63.76) at implementation sites. The incremental population-level cost-effectiveness ratio was $33,905.92/QALY (bootstrap interquartile range −$45,343.10/QALY to $99,260.90/QALY). Conclusions The methodology was feasible to operationalize and gave reasonable estimates of implementation value. PMID:25328029

Brain Training in Children and Adolescents: Is It Scientifically Valid?

PubMed

Rossignoli-Palomeque, Teresa; Perez-Hernandez, Elena; González-Marqués, Javier

2018-01-01

Background: Brain training products are becoming increasingly popular for children and adolescents. Despite the marketing aimed at their use in the general population, these products may provide more benefits for specific neurologically impaired populations. A review of Brain Training (BT) products analyzing their efficacy while considering the methodological limitations of supporting research is required for practical applications. Method: searches were made of the PubMed database (until March 2017) for studies including: (1) empirical data on the use of brain training for children or adolescents and any effects on near transfer (NT) and/or far transfer (FT) and/or neuroplasticity, (2) use of brain training for cognitive training purposes, (3) commercially available training applications, (4) computer-based programs for children developed since the 1990s, and (5) relevant printed and peer-reviewed material. Results: Database searches yielded a total of 16,402 references, of which 70 met the inclusion criteria for the review. We classified programs in terms of neuroplasticity, near and far transfer, and long-term effects and their applied methodology. Regarding efficacy, only 10 studies (14.2%) have been found that support neuroplasticity, and the majority of brain training platforms claimed to be based on such concepts without providing any supporting scientific data. Thirty-six studies (51.4%) have shown far transfer (7 of them are non-independent) and only 11 (15.7%) maintained far transfer at follow-up. Considering the methodology, 40 studies (68.2%) were not randomized and controlled; for those randomized, only 9 studies (12.9%) were double-blind, and only 13 studies (18.6%) included active controls in their trials. Conclusion: Overall, few independent studies have found far transfer and long-term effects. The majority of independent results found only near transfer. There is a lack of double-blind randomized trials which include an active control group as well as a passive control to properly control for contaminant variables. Based on our results, Brain Training Programs as commercially available products are not as effective as first expected or as they promise in their advertisements.

Brain Training in Children and Adolescents: Is It Scientifically Valid?

PubMed Central

Rossignoli-Palomeque, Teresa; Perez-Hernandez, Elena; González-Marqués, Javier

2018-01-01

Background: Brain training products are becoming increasingly popular for children and adolescents. Despite the marketing aimed at their use in the general population, these products may provide more benefits for specific neurologically impaired populations. A review of Brain Training (BT) products analyzing their efficacy while considering the methodological limitations of supporting research is required for practical applications. Method: searches were made of the PubMed database (until March 2017) for studies including: (1) empirical data on the use of brain training for children or adolescents and any effects on near transfer (NT) and/or far transfer (FT) and/or neuroplasticity, (2) use of brain training for cognitive training purposes, (3) commercially available training applications, (4) computer-based programs for children developed since the 1990s, and (5) relevant printed and peer-reviewed material. Results: Database searches yielded a total of 16,402 references, of which 70 met the inclusion criteria for the review. We classified programs in terms of neuroplasticity, near and far transfer, and long-term effects and their applied methodology. Regarding efficacy, only 10 studies (14.2%) have been found that support neuroplasticity, and the majority of brain training platforms claimed to be based on such concepts without providing any supporting scientific data. Thirty-six studies (51.4%) have shown far transfer (7 of them are non-independent) and only 11 (15.7%) maintained far transfer at follow-up. Considering the methodology, 40 studies (68.2%) were not randomized and controlled; for those randomized, only 9 studies (12.9%) were double-blind, and only 13 studies (18.6%) included active controls in their trials. Conclusion: Overall, few independent studies have found far transfer and long-term effects. The majority of independent results found only near transfer. There is a lack of double-blind randomized trials which include an active control group as well as a passive control to properly control for contaminant variables. Based on our results, Brain Training Programs as commercially available products are not as effective as first expected or as they promise in their advertisements. PMID:29780336

Drug research methodology. Volume 5, Experimentation in drugs and highway safety : the study of drug effects on skills related to driving

DOT National Transportation Integrated Search

1980-06-01

This report presents the findings of a workshop on experimental research in the area of drugs and highway safety. Complementing studies of drug use in different driving populations, experimentation here refers to studies performed under controlled co...

Inducing Speech Errors in Dysarthria Using Tongue Twisters

ERIC Educational Resources Information Center

Kember, Heather; Connaghan, Kathryn; Patel, Rupal

2017-01-01

Although tongue twisters have been widely use to study speech production in healthy speakers, few studies have employed this methodology for individuals with speech impairment. The present study compared tongue twister errors produced by adults with dysarthria and age-matched healthy controls. Eight speakers (four female, four male; mean age =…

A Validated Methodology for Genetic Identification of Tuna Species (Genus Thunnus)

PubMed Central

Viñas, Jordi; Tudela, Sergi

2009-01-01

Background Tuna species of the genus Thunnus, such as the bluefin tunas, are some of the most important and yet most endangered trade fish in the world. Identification of these species in traded forms, however, may be difficult depending on the presentation of the products, which may hamper conservation efforts on trade control. In this paper, we validated a genetic methodology that can fully distinguish between the eight Thunnus species from any kind of processed tissue. Methodology After testing several genetic markers, a complete discrimination of the eight tuna species was achieved using Forensically Informative Nucleotide Sequencing based primarily on the sequence variability of the hypervariable genetic marker mitochondrial DNA control region (mtDNA CR), followed, in some specific cases, by a second validation by a nuclear marker rDNA first internal transcribed spacer (ITS1). This methodology was able to distinguish all tuna species, including those belonging to the subgenus Neothunnus that are very closely related, and in consequence can not be differentiated with other genetic markers of lower variability. This methodology also took into consideration the presence of introgression that has been reported in past studies between T. thynnus, T. orientalis and T. alalunga. Finally, we applied the methodology to cross-check the species identity of 26 processed tuna samples. Conclusions Using the combination of two genetic markers, one mitochondrial and another nuclear, allows a full discrimination between all eight tuna species. Unexpectedly, the genetic marker traditionally used for DNA barcoding, cytochrome oxidase 1, could not differentiate all species, thus its use as a genetic marker for tuna species identification is questioned. PMID:19898615

Update on the Methodological Quality of Research Published in The American Journal of Sports Medicine: Comparing 2011-2013 to 10 and 20 Years Prior.

PubMed

Brophy, Robert H; Kluck, Dylan; Marx, Robert G

2016-05-01

In recent years, the number of articles in The American Journal of Sports Medicine (AJSM) has risen dramatically, with an increasing emphasis on evidence-based medicine in orthopaedics and sports medicine. Despite the increase in the number of articles published in AJSM over the past decade, the methodological quality of articles in 2011-2013 has improved relative to those in 2001-2003 and 1991-1993. Meta-analysis. All articles published in AJSM during 2011-2013 were reviewed and classified by study design. For each article, the use of pertinent methodologies, such as prospective data collection, randomization, control groups, and blinding, was recorded. The frequency of each article type and the use of evidence-based techniques were compared relative to 1991-1993 and 2001-2003 by use of Pearson χ(2) testing. The number of research articles published in AJSM more than doubled from 402 in 1991-1993 and 423 in 2001-2003 to 953 in 2011-2013. Case reports decreased from 15.2% to 10.6% to 2.1% of articles published over the study period (P < .001). Cadaveric/human studies and meta-analysis/literature review studies increased from 5.7% to 7.1% to 12.4% (P < .001) and from 0.2% to 0.9% to 2.3% (P = .01), respectively. Randomized, prospective clinical trials increased from 2.7% to 5.9% to 7.4% (P = .007). Fewer studies used retrospective compared with prospective data collection (P < .001). More studies tested an explicit hypothesis (P < .001) and used controls (P < .001), randomization (P < .001), and blinding of those assessing outcomes (P < .001). Multi-investigator trials increased (P < .001), as did the proportion of articles citing a funding source (P < .001). Despite a dramatic increase in the number of published articles, the research published in AJSM shifted toward more prospective, randomized, controlled, and blinded designs during 2011-2013 compared with 2001-2003 and 1991-1993, demonstrating a continued improvement in methodological quality. © 2015 The Author(s).

Electric and hybrid vehicles environmental control subsystem study

NASA Technical Reports Server (NTRS)

1981-01-01

An environmental control subsystem (ECS) in the passenger compartment of electric and hybrid vehicles is studied. Various methods of obtaining the desired temperature control for the battery pack is also studied. The functional requirements of ECS equipment is defined. Following categorization by methodology, technology availability and risk, all viable ECS concepts are evaluated. Each is assessed independently for benefits versus risk, as well as for its feasibility to short, intermediate and long term product development. Selection of the preferred concept is made against these requirements, as well as the study's major goal of providing safe, highly efficient and thermally confortable ECS equipment.

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.

School-Based Service-Learning for Promoting Citizenship in Young People: A Systematic Review

DTIC Science & Technology

2005-09-06

nonequivalent pre- and post-test design with control group was utilized but participants were not randomized to groups . The sample...other methodology. She notes the limitations of the research chosen for the review (i.e., most studies lack a control group , do not track effects over...experimental and control groups Pre- and post- test design Surveys “Service-learning”12 Intervention groups : Service-learning

75 FR 13076 - Privacy Act of 1974; Altered System of Records

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-18

....C., Sections 141 and 193 and the U.S. Census Bureau; and to undertake methodological evaluations and enhancements leading to improved data collection and quality control studies. Also, information collected by...

Evaluation of two spike-and-recovery controls for assessment of extraction efficiency in microbial source tracking studies

USGS Publications Warehouse

Stoeckel, D.M.; Stelzer, E.A.; Dick, L.K.

2009-01-01

Quantitative PCR (qPCR), applied to complex environmental samples such as water, wastewater, and feces, is susceptible to methodological and sample related biases. In this study, we evaluated two exogenous DNA spike-and-recovery controls as proxies for recovery efficiency of Bacteroidales 16S rDNA gene sequences (AllBac and qHF183) that are used for microbial source tracking (MST) in river water. Two controls-(1) the plant pathogen Pantoea stewartii, carrying the chromosomal target gene cpsD, and (2) Escherichia coli, carrying the plasmid-borne target gene DsRed2-were added to raw water samples immediately prior to concentration and DNA extraction for qPCR. When applied to samples processed in replicate, recovery of each control was positively correlated with the observed concentration of each MST marker. Adjustment of MST marker concentrations according to recovery efficiency reduced variability in replicate analyses when consistent processing and extraction methodologies were applied. Although the effects of this procedure on accuracy could not be tested due to uncertainties in control DNA concentrations, the observed reduction in variability should improve the strength of statistical comparisons. These findings suggest that either of the tested spike-and-recovery controls can be useful to measure efficiency of extraction and recovery in routine laboratory processing. ?? 2009 Elsevier Ltd.

Nonlinear analysis of EEG in major depression with fractal dimensions.

PubMed

Akar, Saime A; Kara, Sadik; Agambayev, Sumeyra; Bilgic, Vedat

2015-01-01

Major depressive disorder (MDD) is a psychiatric mood disorder characterized by cognitive and functional impairments in attention, concentration, learning and memory. In order to investigate and understand its underlying neural activities and pathophysiology, EEG methodologies can be used. In this study, we estimated the nonlinearity features of EEG in MDD patients to assess the dynamical properties underlying the frontal and parietal brain activity. EEG data were obtained from 16 patients and 15 matched healthy controls. A wavelet-chaos methodology was used for data analysis. First, EEGs of subjects were decomposed into 5 EEG sub-bands by discrete wavelet transform. Then, both the Katz's and Higuchi's fractal dimensions (KFD and HFD) were calculated as complexity measures for full-band and sub-bands EEGs. Last, two-way analyses of variances were used to test EEG complexity differences on each fractality measures. As a result, a significantly increased complexity was found in both parietal and frontal regions of MDD patients. This significantly increased complexity was observed not only in full-band activity but also in beta and gamma sub-bands of EEG. The findings of the present study indicate the possibility of using the wavelet-chaos methodology to discriminate the EEGs of MDD patients from healthy controls.

RETROFIT COSTS FOR SO2 AND NOX CONTROL OPTIONS AT 200 COAL-FIRED PLANTS, VOLUME I - INTRODUCTION AND METHODOLOGY

EPA Science Inventory

The report gives results of a study, the objective of which was to significantly improve engineering cost estimates currently being used to evaluate the economic effects of applying SO2 and NOx controls at 200 large SO2-emitting coal-fired utility plants. To accomplish the object...

Controlled mass pollination in loblolly pine to increase genetic gains

Treesearch

F.E. Bridgwater; D.L. Bramlett; T.D. Byram; W.J. Lowe

1998-01-01

Controlled mass pollination (CMP) is one way to increase genetic gains from traditional wind-pollinated seed orchards. Methodology is under development by several forestry companies in the southern USA. Costs of CMP depend on the efficient installation, pollination, and removal of inexpensive paper bags. Even in pilot-scale studies these costs seem reasonable. Net...

Locus of Control Orientations in Students with Intellectual Disability, Learning Disabilities, and No Disabilities: A Latent Growth Curve Analysis

ERIC Educational Resources Information Center

Shogren, Karrie A.; Bovaird, James A.; Palmer, Susan B.; Wehmeyer, Michael L.

2010-01-01

Previous research has suggested differences in the locus of control (LOC) orientations of students with intellectual disability, learning disabilities, and no disabilities, although this research has been characterized by methodological limitations. The purpose of this study was to examine the development of LOC orientations in students with…

Methodology for Determination of Grade Crossing Resource-Allocation Guidelines

DOT National Transportation Integrated Search

1975-04-01

The primary objective of this study was to determine the most effective method of reducing emissions of oxides of nitrogen from a two-cylinder version of an EMD series 567C locomotive engine. The NOx control techniques selected for use in this study ...

76 FR 68385 - Approval and Promulgation of Implementation Plans; New Mexico; Albuquerque/Bernalillo County...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-04

... NMAC) addition of in subsections methodology for (A) and (B). fugitive dust control permits, revised... fee Fee Calculations and requirements for Procedures. fugitive dust control permits. 9/7/2004 Section... schedule based on acreage, add and update calculation methodology used to calculate non- programmatic dust...

Job Rotation Designed to Prevent Musculoskeletal Disorders and Control Risk in Manufacturing Industries: A Systematic Review

PubMed Central

Padula, Rosimeire Simprini; Comper, Maria Luiza Caires; Sparer, Emily H.; Dennerlein, Jack T

2017-01-01

To better understand job rotation in the manufacturing industry, we completed a systematic review asking the following questions: 1) How do job-rotation programs impact work-related musculoskeletal disorders (MSDs) and related risk control for these MSDs, as well as psychosocial factors? and 2) How best should the job rotation programs be designed? We searched MEDLINE, EMBASE, Business Source Premier, ISI Web of Knowledge, CINAHL, PsyINFO, Scopus, and SciELO databases for articles published in peer-reviewed journals. Eligible studies were examined by two independent reviewers for relevance (population of manufacturing workers, outcomes of musculoskeletal disease, physical factors, psychosocial factors, and strategies used in job-rotation implantation) and methodological quality rating. From 10,809 potential articles, 71 were read for full text analysis. Of the 14 studies included for data extraction, two were non-randomized control trial studies, one was a case-control study, and 11 were cross-sectional comparisons. Only one, with a case-control design, was scored with good methodological quality. Currently, weak evidence exists supporting job rotation as a strategy for the prevention and control of musculoskeletal disorders. Job rotation did not appear to reduce the exposure of physical risk factors; yet, there are positive correlations between job rotation and higher job satisfaction. Worker training has been described as a crucial component of a successful job-rotation program. The studies reported a range of parameters used to implement and measure job-rotation programs. More rigorous studies are needed to better understand the full impact of job rotation on production and health. PMID:27633235

On the methodology of Engineering Geodesy

NASA Astrophysics Data System (ADS)

Brunner, Fritz K.

2007-09-01

Textbooks on geodetic surveying usually describe a very small number of principles which should provide the foundation of geodetic surveying. Here, the author argues that an applied field, such as engineering geodesy, has a methodology as foundation rather than a few principles. Ten methodological elements (ME) are identified: (1) Point discretisation of natural surfaces and objects, (2) distinction between coordinate and observation domain, (3) definition of reference systems, (4) specification of unknown parameters and desired precisions, (5) geodetic network and observation design, (6) quality control of equipment, (7) quality control of measurements, (8) establishment of measurement models, (9) establishment of parameter estimation models, (10) quality control of results. Each ME consists of a suite of theoretical developments, geodetic techniques and calculation procedures, which will be discussed. This paper is to be considered a first attempt at identifying the specific elements of the methodology of engineering geodesy. A better understanding of this methodology could lead to an increased objectivity, to a transformation of subjective practical experiences into objective working methods, and consequently to a new structure for teaching this rather diverse subject.

A generic methodology for the optimisation of sewer systems using stochastic programming and self-optimizing control.

PubMed

Mauricio-Iglesias, Miguel; Montero-Castro, Ignacio; Mollerup, Ane L; Sin, Gürkan

2015-05-15

The design of sewer system control is a complex task given the large size of the sewer networks, the transient dynamics of the water flow and the stochastic nature of rainfall. This contribution presents a generic methodology for the design of a self-optimising controller in sewer systems. Such controller is aimed at keeping the system close to the optimal performance, thanks to an optimal selection of controlled variables. The definition of an optimal performance was carried out by a two-stage optimisation (stochastic and deterministic) to take into account both the overflow during the current rain event as well as the expected overflow given the probability of a future rain event. The methodology is successfully applied to design an optimising control strategy for a subcatchment area in Copenhagen. The results are promising and expected to contribute to the advance of the operation and control problem of sewer systems. Copyright © 2015 Elsevier Ltd. All rights reserved.

Net-zero Building Cluster Simulations and On-line Energy Forecasting for Adaptive and Real-Time Control and Decisions

NASA Astrophysics Data System (ADS)

Li, Xiwang

Buildings consume about 41.1% of primary energy and 74% of the electricity in the U.S. Moreover, it is estimated by the National Energy Technology Laboratory that more than 1/4 of the 713 GW of U.S. electricity demand in 2010 could be dispatchable if only buildings could respond to that dispatch through advanced building energy control and operation strategies and smart grid infrastructure. In this study, it is envisioned that neighboring buildings will have the tendency to form a cluster, an open cyber-physical system to exploit the economic opportunities provided by a smart grid, distributed power generation, and storage devices. Through optimized demand management, these building clusters will then reduce overall primary energy consumption and peak time electricity consumption, and be more resilient to power disruptions. Therefore, this project seeks to develop a Net-zero building cluster simulation testbed and high fidelity energy forecasting models for adaptive and real-time control and decision making strategy development that can be used in a Net-zero building cluster. The following research activities are summarized in this thesis: 1) Development of a building cluster emulator for building cluster control and operation strategy assessment. 2) Development of a novel building energy forecasting methodology using active system identification and data fusion techniques. In this methodology, a systematic approach for building energy system characteristic evaluation, system excitation and model adaptation is included. The developed methodology is compared with other literature-reported building energy forecasting methods; 3) Development of the high fidelity on-line building cluster energy forecasting models, which includes energy forecasting models for buildings, PV panels, batteries and ice tank thermal storage systems 4) Small scale real building validation study to verify the performance of the developed building energy forecasting methodology. The outcomes of this thesis can be used for building cluster energy forecasting model development and model based control and operation optimization. The thesis concludes with a summary of the key outcomes of this research, as well as a list of recommendations for future work.

Intra-Articular Cellular Therapy for Osteoarthritis and Focal Cartilage Defects of the Knee: A Systematic Review of the Literature and Study Quality Analysis.

PubMed

Chahla, Jorge; Piuzzi, Nicolas S; Mitchell, Justin J; Dean, Chase S; Pascual-Garrido, Cecilia; LaPrade, Robert F; Muschler, George F

2016-09-21

Intra-articular cellular therapy injections constitute an appealing strategy that may modify the intra-articular milieu or regenerate cartilage in the settings of osteoarthritis and focal cartilage defects. However, little consensus exists regarding the indications for cellular therapies, optimal cell sources, methods of preparation and delivery, or means by which outcomes should be reported. We present a systematic review of the current literature regarding the safety and efficacy of cellular therapy delivered by intra-articular injection in the knee that provided a Level of Evidence of III or higher. A total of 420 papers were screened. Methodological quality was assessed using a modified Coleman methodology score. Only 6 studies (4 Level II and 2 Level III) met the criteria to be included in this review; 3 studies were on treatment of osteoarthritis and 3 were on treatment of focal cartilage defects. These included 4 randomized controlled studies without blinding, 1 prospective cohort study, and 1 retrospective therapeutic case-control study. The studies varied widely with respect to cell sources, cell characterization, adjuvant therapies, and assessment of outcomes. Outcome was reported in a total of 300 knees (124 in the osteoarthritis studies and 176 in the cartilage defect studies). Mean follow-up was 21.0 months (range, 12 to 36 months). All studies reported improved outcomes with intra-articular cellular therapy and no major adverse events. The mean modified Coleman methodology score was 59.1 ± 16 (range, 32 to 82). The studies of intra-articular cellular therapy injections for osteoarthritis and focal cartilage defects in the human knee suggested positive results with respect to clinical improvement and safety. However, the improvement was modest and a placebo effect cannot be disregarded. The overall quality of the literature was poor, and the methodological quality was fair, even among Level-II and III studies. Effective clinical assessment and optimization of injection therapies will demand greater attention to study methodology, including blinding; standardized quantitative methods for cell harvesting, processing, characterization, and delivery; and standardized reporting of clinical and structural outcomes. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence. Copyright © 2016 by The Journal of Bone and Joint Surgery, Incorporated.

Development of a Design Methodology for Reconfigurable Flight Control Systems

NASA Technical Reports Server (NTRS)

Hess, Ronald A.; McLean, C.

2000-01-01

A methodology is presented for the design of flight control systems that exhibit stability and performance-robustness in the presence of actuator failures. The design is based upon two elements. The first element consists of a control law that will ensure at least stability in the presence of a class of actuator failures. This law is created by inner-loop, reduced-order, linear dynamic inversion, and outer-loop compensation based upon Quantitative Feedback Theory. The second element consists of adaptive compensators obtained from simple and approximate time-domain identification of the dynamics of the 'effective vehicle' with failed actuator(s). An example involving the lateral-directional control of a fighter aircraft is employed both to introduce the proposed methodology and to demonstrate its effectiveness and limitations.

On the importance of methods in hydrological modelling. Perspectives from a case study

NASA Astrophysics Data System (ADS)

Fenicia, Fabrizio; Kavetski, Dmitri

2017-04-01

The hydrological community generally appreciates that developing any non-trivial hydrological model requires a multitude of modelling choices. These choices may range from a (seemingly) straightforward application of mass conservation, to the (often) guesswork-like selection of constitutive functions, parameter values, etc. The application of a model itself requires a myriad of methodological choices - the selection of numerical solvers, objective functions for model calibration, validation approaches, performance metrics, etc. Not unreasonably, hydrologists embarking on ever ambitious projects prioritize hydrological insight over the morass of methodological choices. Perhaps to emphasize "ideas" over "methods", some journals have even reduced the fontsize of the methodology sections of its articles. However, the very nature of modelling is that seemingly routine methodological choices can significantly affect the conclusions of case studies and investigations - making it dangerous to skimp over methodological details in an enthusiastic rush towards the next great hydrological idea. This talk shares modelling insights from a hydrological study of a 300 km2 catchment in Luxembourg, where the diversity of hydrograph dynamics observed at 10 locations begs the question of whether external forcings or internal catchment properties act as dominant controls on streamflow generation. The hydrological insights are fascinating (at least to us), but in this talk we emphasize the impact of modelling methodology on case study conclusions and recommendations. How did we construct our prior set of hydrological model hypotheses? What numerical solver was implemented and why was an objective function based on Bayesian theory deployed? And what would have happened had we omitted model cross-validation, or not used a systematic hypothesis testing approach?

Sexual health education interventions for young people: a methodological review.

PubMed Central

Oakley, A.; Fullerton, D.; Holland, J.; Arnold, S.; France-Dawson, M.; Kelley, P.; McGrellis, S.

1995-01-01

OBJECTIVES--To locate reports of sexual health education interventions for young people, assess the methodological quality of evaluations, identify the subgroup with a methodologically sound design, and assess the evidence with respect to the effectiveness of different approaches to promoting young people's sexual health. DESIGN--Survey of reports in English by means of electronic databases and hand searches for relevant studies conducted in the developed world since 1982. Papers were reviewed for eight methodological qualities. The evidence on effectiveness generated by studies meeting four core criteria was assessed. Judgments on effectiveness by reviewers and authors were compared. PAPERS--270 papers reporting sexual health interventions. MAIN OUTCOME MEASURE--The methodological quality of evaluations. RESULTS--73 reports of evaluations of sexual health interventions examining the effectiveness of these interventions in changing knowledge, attitudes, or behavioural outcomes were identified, of which 65 were separate outcome evaluations. Of these studies, 45 (69%) lacked random control groups, 44 (68%) failed to present preintervention and 38 (59%) postintervention data, and 26 (40%) omitted to discuss the relevance of loss of data caused by drop outs. Only 12 (18%) of the 65 outcome evaluations were judged to be methodologically sound. Academic reviewers were more likely than authors to judge studies as unclear because of design faults. Only two of the sound evaluations recorded interventions which were effective in showing an impact on young people's sexual behaviour. CONCLUSIONS--The design of evaluations in sexual health intervention needs to be improved so that reliable evidence of the effectiveness of different approaches to promoting young people's sexual health may be generated. PMID:7833754

Ginger as an antiemetic modality for chemotherapy-induced nausea and vomiting: a systematic review and meta-analysis.

PubMed

Lee, Jiyeon; Oh, Heeyoung

2013-03-01

To evaluate the effect of ginger as an antiemetic modality for the control of chemotherapy-induced nausea and vomiting (CINV). Databases searched included MEDLINE® (PubMed), Embase, CINAHL®, Cochrane Central Register of Controlled Trials, Korean Studies Information Service System, Research Information Sharing Service by the Korean Education and Research Information Service, and Dissertation Central. A systematic review was conducted of five randomized, controlled trials involving 872 patients with cancer. Ginger was compared with placebo or metoclopramide. The participant characteristics, chemotherapy regimen and antiemetic control, ginger preparation and protocol, measurements, results of the studies, adherence to the treatment protocol, and side effects were reviewed systematically. The incidence and severity of acute and delayed CINV were subject to meta-analysis. The incidence of acute nausea (p = 0.67), incidence of acute vomiting (p = 0.37), and severity of acute nausea (p = 0.12) did not differ significantly between the ginger and control groups. Current evidence does not support the use of ginger for the control of CINV. Ginger did not contribute to control of the incidence of acute nausea and vomiting or of the severity of acute nausea. Ginger has long been regarded as a traditional antiemetic modality, but its effectiveness remains to be established. The findings of this study could be incorporated into clinical guidelines, such as the Oncology Nursing Society's Putting Evidence Into Practice resources. Current evidence supports the need for more methodologically rigorous studies in this area. Although ginger is known as a traditional antiemetic, current evidence does not support the effect of ginger in CINV control. The findings of this study inform healthcare providers that its effectiveness remains to be established from methodologically rigorous future trials.

A new methodology based on functional principal component analysis to study postural stability post-stroke.

PubMed

Sánchez-Sánchez, M Luz; Belda-Lois, Juan-Manuel; Mena-Del Horno, Silvia; Viosca-Herrero, Enrique; Igual-Camacho, Celedonia; Gisbert-Morant, Beatriz

2018-05-05

A major goal in stroke rehabilitation is the establishment of more effective physical therapy techniques to recover postural stability. Functional Principal Component Analysis provides greater insight into recovery trends. However, when missing values exist, obtaining functional data presents some difficulties. The purpose of this study was to reveal an alternative technique for obtaining the Functional Principal Components without requiring the conversion to functional data beforehand and to investigate this methodology to determine the effect of specific physical therapy techniques in balance recovery trends in elderly subjects with hemiplegia post-stroke. A randomized controlled pilot trial was developed. Thirty inpatients post-stroke were included. Control and target groups were treated with the same conventional physical therapy protocol based on functional criteria, but specific techniques were added to the target group depending on the subjects' functional level. Postural stability during standing was quantified by posturography. The assessments were performed once a month from the moment the participants were able to stand up to six months post-stroke. The target group showed a significant improvement in postural control recovery trend six months after stroke that was not present in the control group. Some of the assessed parameters revealed significant differences between treatment groups (P < 0.05). The proposed methodology allows Functional Principal Component Analysis to be performed when data is scarce. Moreover, it allowed the dynamics of recovery of two different treatment groups to be determined, showing that the techniques added in the target group increased postural stability compared to the base protocol. Copyright © 2018 Elsevier Ltd. All rights reserved.

A shared position/force control methodology for teleoperation

NASA Technical Reports Server (NTRS)

Lee, Jin S.

1987-01-01

A flexible and computationally efficient shared position/force control concept and its implementation in the Robot Control C Library (RCCL) are presented form the point of teleoperation. This methodology enables certain degrees of freedom to be position-controlled through real time manual inputs and the remaining degrees of freedom to be force-controlled by computer. Functionally, it is a hybrid control scheme in that certain degrees of freedom are designated to be under position control, and the remaining degrees of freedom to be under force control. However, the methodology is also a shared control scheme because some degrees of freedom can be put under manual control and the other degrees of freedom put under computer control. Unlike other hybrid control schemes, which process position and force commands independently, this scheme provides a force control loop built on top of a position control inner loop. This feature minimizes the computational burden and increases disturbance rejection. A simple implementation is achieved partly because the joint control servos that are part of most robots can be used to provide the position control inner loop. Along with this control scheme, several menus were implemented for the convenience of the user. The implemented control scheme was successfully demonstrated for the tasks of hinged-panel opening and peg-in-hole insertion.

SCAP: a new methodology for safety management based on feedback from credible accident-probabilistic fault tree analysis system.

PubMed

Khan, F I; Iqbal, A; Ramesh, N; Abbasi, S A

2001-10-12

As it is conventionally done, strategies for incorporating accident--prevention measures in any hazardous chemical process industry are developed on the basis of input from risk assessment. However, the two steps-- risk assessment and hazard reduction (or safety) measures--are not linked interactively in the existing methodologies. This prevents a quantitative assessment of the impacts of safety measures on risk control. We have made an attempt to develop a methodology in which risk assessment steps are interactively linked with implementation of safety measures. The resultant system tells us the extent of reduction of risk by each successive safety measure. It also tells based on sophisticated maximum credible accident analysis (MCAA) and probabilistic fault tree analysis (PFTA) whether a given unit can ever be made 'safe'. The application of the methodology has been illustrated with a case study.

On synchronisation of a class of complex chaotic systems with complex unknown parameters via integral sliding mode control

NASA Astrophysics Data System (ADS)

Tirandaz, Hamed; Karami-Mollaee, Ali

2018-06-01

Chaotic systems demonstrate complex behaviour in their state variables and their parameters, which generate some challenges and consequences. This paper presents a new synchronisation scheme based on integral sliding mode control (ISMC) method on a class of complex chaotic systems with complex unknown parameters. Synchronisation between corresponding states of a class of complex chaotic systems and also convergence of the errors of the system parameters to zero point are studied. The designed feedback control vector and complex unknown parameter vector are analytically achieved based on the Lyapunov stability theory. Moreover, the effectiveness of the proposed methodology is verified by synchronisation of the Chen complex system and the Lorenz complex systems as the leader and the follower chaotic systems, respectively. In conclusion, some numerical simulations related to the synchronisation methodology is given to illustrate the effectiveness of the theoretical discussions.

Feasibility and benefits of laminar flow control on supersonic cruise airplanes

NASA Technical Reports Server (NTRS)

Powell, A. G.; Agrawal, S.; Lacey, T. R.

1989-01-01

An evaluation was made of the applicability and benefits of laminar flow control (LFC) technology to supersonic cruise airplanes. Ancillary objectives were to identify the technical issues critical to supersonic LFC application, and to determine how those issues can be addressed through flight and wind-tunnel testing. Vehicle types studied include a Mach 2.2 supersonic transport configuration, a Mach 4.0 transport, and two Mach 2-class fighter concepts. Laminar flow control methodologies developed for subsonic and transonic wing laminarization were extended and applied. No intractible aerodynamic problems were found in applying LFC to airplanes of the Mach 2 class, even ones of large size. Improvements of 12 to 17 percent in lift-drag ratios were found. Several key technical issues, such as contamination avoidance and excresence criteria were identified. Recommendations are made for their resolution. A need for an inverse supersonic wing design methodology is indicated.

Application of Control Volume Analysis to Cerebrospinal Fluid Dynamics

NASA Astrophysics Data System (ADS)

Wei, Timothy; Cohen, Benjamin; Anor, Tomer; Madsen, Joseph

2011-11-01

Hydrocephalus is among the most common birth defects and may not be prevented nor cured. Afflicted individuals face serious issues, which at present are too complicated and not well enough understood to treat via systematic therapies. This talk outlines the framework and application of a control volume methodology to clinical Phase Contrast MRI data. Specifically, integral control volume analysis utilizes a fundamental, fluid dynamics methodology to quantify intracranial dynamics within a precise, direct, and physically meaningful framework. A chronically shunted, hydrocephalic patient in need of a revision procedure was used as an in vivo case study. Magnetic resonance velocity measurements within the patient's aqueduct were obtained in four biomedical state and were analyzed using the methods presented in this dissertation. Pressure force estimates were obtained, showing distinct differences in amplitude, phase, and waveform shape for different intracranial states within the same individual. Thoughts on the physiological and diagnostic research and development implications/opportunities will be presented.

Cost comparisons and methodological heterogeneity in cost-of-illness studies: the example of colorectal cancer.

PubMed

Ó Céilleachair, Alan J; Hanly, Paul; Skally, Máiréad; O'Neill, Ciaran; Fitzpatrick, Patricia; Kapur, Kanika; Staines, Anthony; Sharp, Linda

2013-04-01

Colorectal cancer (CRC) is the third most common cancer worldwide with over 1 million new cases diagnosed each year. Advances in treatment and survival are likely to have increased lifetime costs of managing the disease. Cost-of-illness (COI) studies are key building blocks in economic evaluations of interventions and comparative effectiveness research. We systematically reviewed and critiqued the COI literature on CRC. We searched several databases for CRC COI studies published in English, between January 2000 and February 2011. Information was abstracted on: setting, patient population, top-down/bottom-up costing, incident/prevalent approach, payer perspective, time horizon, costs included, cost source, and per-person costs. We developed a framework to compare study methodologies and assess homogeneity/heterogeneity. A total of 26 papers met the inclusion criteria. There was extensive methodological heterogeneity. Studies included case-control studies based on claims/reimbursement data (10), examinations of patient charts (5), and analysis of claims data (4). Epidemiological approaches varied (prevalent, 6; incident, 8; mixed, 10; unclear, 4). Time horizons ranged from 1 year postdiagnosis to lifetime. Seventeen studies used top-down costing. Twenty-five studies included healthcare-payer direct medical costs; 2 included indirect costs; 1 considered patient costs. There was broad agreement in how studies accounted for time, but few studies described costs in sufficient detail to allow replication. In general, costs were not comparable between studies. Methodological heterogeneity and lack of transparency made it almost impossible to compare CRC costs between studies or over time. For COI studies to be more useful and robust there is need for clear and rigorous guidelines around methodological and reporting "best practice."

Research and development activities in unified control-structure modeling and design

NASA Technical Reports Server (NTRS)

Nayak, A. P.

1985-01-01

Results of work sponsored by JPL and other organizations to develop a unified control/structures modeling and design capability for large space structures is presented. Recent analytical results are presented to demonstrate the significant interdependence between structural and control properties. A new design methodology is suggested in which the structure, material properties, dynamic model and control design are all optimized simultaneously. The development of a methodology for global design optimization is recommended as a long term goal. It is suggested that this methodology should be incorporated into computer aided engineering programs, which eventually will be supplemented by an expert system to aid design optimization. Recommendations are also presented for near term research activities at JPL. The key recommendation is to continue the development of integrated dynamic modeling/control design techniques, with special attention given to the development of structural models specially tailored to support design.

Coordinative Voltage Control Strategy with Multiple Resources for Distribution Systems of High PV Penetration: Preprint

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

Zhu, Xiangqi; Zhang, Yingchen

This paper presents an optimal voltage control methodology with coordination among different voltage-regulating resources, including controllable loads, distributed energy resources such as energy storage and photovoltaics (PV), and utility voltage-regulating devices such as voltage regulators and capacitors. The proposed methodology could effectively tackle the overvoltage and voltage regulation device distortion problems brought by high penetrations of PV to improve grid operation reliability. A voltage-load sensitivity matrix and voltage-regulator sensitivity matrix are used to deploy the resources along the feeder to achieve the control objectives. Mixed-integer nonlinear programming is used to solve the formulated optimization control problem. The methodology has beenmore » tested on the IEEE 123-feeder test system, and the results demonstrate that the proposed approach could actively tackle the voltage problem brought about by high penetrations of PV and improve the reliability of distribution system operation.« less

Focus control enhancement and on-product focus response analysis methodology

NASA Astrophysics Data System (ADS)

Kim, Young Ki; Chen, Yen-Jen; Hao, Xueli; Samudrala, Pavan; Gomez, Juan-Manuel; Mahoney, Mark O.; Kamalizadeh, Ferhad; Hanson, Justin K.; Lee, Shawn; Tian, Ye

2016-03-01

With decreasing CDOF (Critical Depth Of Focus) for 20/14nm technology and beyond, focus errors are becoming increasingly critical for on-product performance. Current on product focus control techniques in high volume manufacturing are limited; It is difficult to define measurable focus error and optimize focus response on product with existing methods due to lack of credible focus measurement methodologies. Next to developments in imaging and focus control capability of scanners and general tool stability maintenance, on-product focus control improvements are also required to meet on-product imaging specifications. In this paper, we discuss focus monitoring, wafer (edge) fingerprint correction and on-product focus budget analysis through diffraction based focus (DBF) measurement methodology. Several examples will be presented showing better focus response and control on product wafers. Also, a method will be discussed for a focus interlock automation system on product for a high volume manufacturing (HVM) environment.

Optimal scheduling and its Lyapunov stability for advanced load-following energy plants with CO 2 capture

DOE PAGES

Bankole, Temitayo; Jones, Dustin; Bhattacharyya, Debangsu; ...

2017-11-03

In this study, a two-level control methodology consisting of an upper-level scheduler and a lower-level supervisory controller is proposed for an advanced load-following energy plant with CO 2 capture. With the use of an economic objective function that considers fluctuation in electricity demand and price at the upper level, optimal scheduling of energy plant electricity production and carbon capture with respect to several carbon tax scenarios is implemented. The optimal operational profiles are then passed down to corresponding lower-level supervisory controllers designed using a methodological approach that balances control complexity with performance. Finally, it is shown how optimal carbon capturemore » and electricity production rate profiles for an energy plant such as the integrated gasification combined cycle (IGCC) plant are affected by electricity demand and price fluctuations under different carbon tax scenarios. As a result, the paper also presents a Lyapunov stability analysis of the proposed scheme.« less

Optimal scheduling and its Lyapunov stability for advanced load-following energy plants with CO 2 capture

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

Bankole, Temitayo; Jones, Dustin; Bhattacharyya, Debangsu

In this study, a two-level control methodology consisting of an upper-level scheduler and a lower-level supervisory controller is proposed for an advanced load-following energy plant with CO 2 capture. With the use of an economic objective function that considers fluctuation in electricity demand and price at the upper level, optimal scheduling of energy plant electricity production and carbon capture with respect to several carbon tax scenarios is implemented. The optimal operational profiles are then passed down to corresponding lower-level supervisory controllers designed using a methodological approach that balances control complexity with performance. Finally, it is shown how optimal carbon capturemore » and electricity production rate profiles for an energy plant such as the integrated gasification combined cycle (IGCC) plant are affected by electricity demand and price fluctuations under different carbon tax scenarios. As a result, the paper also presents a Lyapunov stability analysis of the proposed scheme.« less

Platelet-Rich Plasma (PRP) for Acute Muscle Injury: A Systematic Review

PubMed Central

A. Hamid, Mohamad Shariff; Yusof, Ashril; Mohamed Ali, Mohamed Razif

2014-01-01

Introduction Acute muscle injury is one of the commonest injuries that often result in loss of training and competition time. The best management for muscle injury has not been identified. Sports medicine practitioners used several approaches in attempt to accelerate time to recovery from muscle injury. More recently growing interest focussed on autologous blood product injection. Methods A literature search was conducted systematically using OvidMEDLINE, PubMed, EMBASE, SPORTDiscus and CINAHL databases to retrieve articles published until December 2012. Controlled trials and controlled laboratory studies comparing different strategies to promote early recovery of muscle injury were included. The methodological quality of studies was assessed. Results There are limited studies on the effects of PRP therapy for muscle injury. Three in vivo laboratory studies and one pilot human study were reviewed. The laboratory studies reported histological evidence on significant acceleration of muscle healing in animals treated with autologous conditioned serum (ACS), platelet-rich plasma (PRP) and platelet rich fibrin matrix (PRFM). A pilot human study found athletes treated with repeated ACS injection recovers significantly faster than retrospective controls. Conclusion Several in vivo laboratory studies suggest beneficial effects of ACS, PRP and PRFM in accelerating muscle recovery. Evidence to suggest similar effects on humans is however limited, as valuable information from robust human controlled trials is still not available at this moment. Hence, more studies of satisfactory methodological quality with platelet-rich plasma interventions on muscle injury are justified. PMID:24587389

Irritable Bowel Syndrome and Complementary Health Practices: What the Science Says

MedlinePlus

... controlled trials on various herbal preparations; however, the methodological quality of most of these studies is poor. ... if improperly manufactured. A 2012 systematic review of case reports and case series concluded that using certain ...

Thermal Control System for a Small, Extended Duration Lunar Surface Science Platform

NASA Technical Reports Server (NTRS)

Bugby, D.; Farmer, J.; OConnor, B.; Wirzburger, M.; Abel, E.; Stouffer, C.

2010-01-01

The presentation slides include: Introduction: lunar mission definition, Problem: requirements/methodology, Concept: thermal switching options, Analysis: system evaluation, Plans: dual-radiator LHP (loop heat pipe) test bed, and Conclusions: from this study.

MERCURY MEASUREMENTS USING DIRECT-ANALYZER METHODOLOGY

EPA Science Inventory

Under EPA's Water Quality Research Program, exposure studies are needed to determine how well control strategies and guidance are working. Consequently, reliable and convenient techniques that minimize waste production are of special interest. While traditional methods for determ...

Payload/orbiter contamination control requirement study: Spacelab configuration contamination study

NASA Technical Reports Server (NTRS)

Bareiss, L. E.; Hetrick, M. A.; Ress, E. B.; Strange, D. A.

1976-01-01

The assessment of the Spacelab carrier induced contaminant environment was continued, and the ability of Spacelab to meet established contamination control criteria for the space transportation system program was determined. The primary areas considered included: (1) updating, refining, and improving the Spacelab contamination computer model and contamination analysis methodology, (2) establishing the resulting adjusted induced environment predictions for comparison with the applicable criteria, (3) determining the Spacelab design and operational requirements necessary to meet the criteria, (4) conducting mission feasibility analyses of the combined Spacelab/Orbiter contaminant environment for specific proposed mission and payload mixes, and (5) establishing a preliminary Spacelab mission support plan as well as model interface requirements; A summary of those activities conducted to date with respect to the modelling, analysis, and predictions of the induced environment, including any modifications in approach or methodology utilized in the contamination assessment of the Spacelab carrier, was presented.

Mindfulness Meditation for Substance Use Disorders: A Systematic Review

PubMed Central

Zgierska, Aleksandra; Rabago, David; Chawla, Neharika; Kushner, Kenneth; Koehler, Robert; Marlatt, Allan

2009-01-01

Relapse is common in substance use disorders (SUDs), even among treated individuals. The goal of this article was to systematically review the existing evidence on mindfulness meditation-based interventions (MM) for SUDs. The comprehensive search for and review of literature found over 2,000 abstracts and resulted in 25 eligible manuscripts (22 published, 3 unpublished: 8 RCTs, 7 controlled non-randomized, 6 non-controlled prospective, 2 qualitative studies, 1 case report). When appropriate, methodological quality, absolute risk reduction, number needed to treat, and effect size (ES) were assessed. Overall, although preliminary evidence suggests MM efficacy and safety, conclusive data for MM as a treatment of SUDs are lacking. Significant methodological limitations exist in most studies. Further, it is unclear which persons with SUDs might benefit most from MM. Future trials must be of sufficient sample size to answer a specific clinical question and should target both assessment of effect size and mechanisms of action. PMID:19904664

Psychologically mediated effects of the physical healthcare environment on work-related outcomes of healthcare personnel.

PubMed

Tanja-Dijkstra, Karin; Pieterse, Marcel E

2010-12-08

The physical healthcare environment is capable of affecting patients. This concept of 'healing environments' refers to the psychological impact of environmental stimuli through sensory perceptions. It excludes more physiological effects such as those produced by ergonomic (i.e. fall prevention) or facilitative (i.e. hygiene-related) variables. The importance of an atmosphere in the healthcare environment that promotes the health and well-being of patients is evident, but this environment should not negatively affect healthcare personnel. The physical healthcare environment is part of the personnel's 'workscape'. This can make the environment an important determinant of subjective work-related outcomes like job satisfaction and well-being, as well as of objective outcomes like absenteeism or quality of care. In order to effectively build or renovate healthcare facilities, it is necessary to pay attention to the needs of both patients and healthcare personnel. To assess the psychological effects of the physical healthcare environment on healthcare personnel. We searched the Cochrane EPOC Group Specialised Register; Cochrane Central Register of Controlled Trials; Database of Abstracts and Reviews of Effects; MEDLINE; EMBASE; CINAHL; Civil Engineering Database and Compendex. We also searched the reference lists of included studies. We included randomised controlled trials (RCT), controlled clinical trials (CCT), controlled before and after studies (CBA), and interrupted time series (ITS) of psychological effects of the physical healthcare environment interventions for healthcare staff. The outcomes included measures of job satisfaction, satisfaction with the physical healthcare environment, quality of life, and quality of care. Two reviewers independently assessed studies for eligibility, extracted data, and assessed methodological quality. We identified one study, which adopted a CBA study design to investigate the simultaneous effects of multiple environmental stimuli. Staff mood improved in this study, while no effects were found on ward atmosphere or unscheduled absences. One study was included in this review. This review therefore indicates that, at present, there is insufficient evidence to support or refute the impact of the physical healthcare environment on work-related outcomes of healthcare staff. Methodological shortcomings, particularly confounding with other variables and the lack of adequate control conditions, partially account for this lack of evidence. Given these methodological issues, the field is in need of well-conducted controlled trials.

The psychological effects of the physical healthcare environment on healthcare personnel.

PubMed

Tanja-Dijkstra, Karin; Pieterse, Marcel E

2011-01-19

The physical healthcare environment is capable of affecting patients. This concept of 'healing environments' refers to the psychological impact of environmental stimuli through sensory perceptions. It excludes more physiological effects such as those produced by ergonomic (i.e. fall prevention) or facilitative (i.e. hygiene-related) variables. The importance of an atmosphere in the healthcare environment that promotes the health and well-being of patients is evident, but this environment should not negatively affect healthcare personnel. The physical healthcare environment is part of the personnel's 'workscape'. This can make the environment an important determinant of subjective work-related outcomes like job satisfaction and well-being, as well as of objective outcomes like absenteeism or quality of care. In order to effectively build or renovate healthcare facilities, it is necessary to pay attention to the needs of both patients and healthcare personnel. To assess the psychological effects of the physical healthcare environment on healthcare personnel. We searched the Cochrane EPOC Group Specialised Register; Cochrane Central Register of Controlled Trials; Database of Abstracts and Reviews of Effects; MEDLINE; EMBASE; CINAHL; Civil Engineering Database and Compendex. We also searched the reference lists of included studies. We included randomised controlled trials (RCT), controlled clinical trials (CCT), controlled before and after studies (CBA), and interrupted time series (ITS) of psychological effects of the physical healthcare environment interventions for healthcare staff. The outcomes included measures of job satisfaction, satisfaction with the physical healthcare environment, quality of life, and quality of care. Two reviewers independently assessed studies for eligibility, extracted data, and assessed methodological quality. We identified one study, which adopted a CBA study design to investigate the simultaneous effects of multiple environmental stimuli. Staff mood improved in this study, while no effects were found on ward atmosphere or unscheduled absences. One study was included in this review. This review therefore indicates that, at present, there is insufficient evidence to support or refute the impact of the physical healthcare environment on work-related outcomes of healthcare staff. Methodological shortcomings, particularly confounding with other variables and the lack of adequate control conditions, partially account for this lack of evidence. Given these methodological issues, the field is in need of well-conducted controlled trials.

Is there relationship between temporomandibular disorders and head and cervical posture? A systematic review.

PubMed

Rocha, C P; Croci, C S; Caria, P H F

2013-11-01

The objective of this systematic review was to find sufficient evidence to deny or accept the association between the head and cervical posture and temporomandibular disorders (TMDs), and thus assist health professionals in the evaluation and treatment of patients with TMDs. A search was conducted through all publications written in English about this topic using the databases from Medline, ISI Web of Science, EMBASE, PubMed and Lilacs. The abstracts that fulfilled the initial guideline were retrieved and evaluated to ensure they met the inclusion criteria. To assess the methodological quality of the studies, we developed a questionnaire considering the following criteria: participant's eligibility, control group, diagnosis of TMDs, posture diagnosis and randomisation. Twenty-two studies were selected as potential studies based on their abstracts. Only seventeen studies actually fulfilled the inclusion criteria. The search provided information about the methodological quality of the studies, in which several methodological defects were found. The evidence presented in this systematic review shows that the relation between TMDs and the head and neck posture is still controversial and unclear. The insufficient number of articles considered of excellent methodological quality is a factor that hinders the acceptance or denial of this association. © 2013 John Wiley & Sons Ltd.

Quasi-experimental designs in practice-based research settings: design and implementation considerations.

PubMed

Handley, Margaret A; Schillinger, Dean; Shiboski, Stephen

2011-01-01

Although randomized controlled trials are often a gold standard for determining intervention effects, in the area of practice-based research (PBR), there are many situations in which individual randomization is not possible. Alternative approaches to evaluating interventions have received increased attention, particularly those that can retain elements of randomization such that they can be considered "controlled" trials. Methodological design elements and practical implementation considerations for two quasi-experimental design approaches that have considerable promise in PBR settings--the stepped-wedge design, and a variant of this design, a wait-list cross-over design, are presented along with a case study from a recent PBR intervention for patients with diabetes. PBR-relevant design features include: creation of a cohort over time that collects control data but allows all participants (clusters or patients) to receive the intervention; staggered introduction of clusters; multiple data collection points; and one-way cross-over into the intervention arm. Practical considerations include: randomization versus stratification, training run in phases; and extended time period for overall study completion. Several design features of practice based research studies can be adapted to local circumstances yet retain elements to improve methodological rigor. Studies that utilize these methods, such as the stepped-wedge design and the wait-list cross-over design, can increase the evidence base for controlled studies conducted within the complex environment of PBR.

Real-time control systems: feedback, scheduling and robustness

NASA Astrophysics Data System (ADS)

Simon, Daniel; Seuret, Alexandre; Sename, Olivier

2017-08-01

The efficient control of real-time distributed systems, where continuous components are governed through digital devices and communication networks, needs a careful examination of the constraints arising from the different involved domains inside co-design approaches. Thanks to the robustness of feedback control, both new control methodologies and slackened real-time scheduling schemes are proposed beyond the frontiers between these traditionally separated fields. A methodology to design robust aperiodic controllers is provided, where the sampling interval is considered as a control variable of the system. Promising experimental results are provided to show the feasibility and robustness of the approach.

An update of a systematic review of controlled clinical trials on the primary prevention of back pain at the workplace.

PubMed

van Poppel, Mireille N M; Hooftman, Wendela E; Koes, Bart W

2004-08-01

To update the evidence on the effectiveness of lumbar supports, education and exercise in the primary prevention of low back pain at the workplace. A computerized search for controlled clinical trials published between 1997 and 2002 was conducted, and the methodological quality of the studies was assessed using a criteria list. The available evidence was graded with a rating system for the level of evidence. Effect sizes of individual studies were combined if the studies were sufficiently similar. Five new papers were identified for the update. These trials were added to the previously available trials (n = 11). The methodological quality of most studies was low. Since three of four RCTs on lumbar supports reported no effect, there is no evidence for the effectiveness of lumbar supports. No evidence for education could be found either, since all six RCTs showed negative results. The four RCTs on exercise consistently reported a positive effect, indicating limited evidence for the effectiveness of exercise. There is no evidence for the effectiveness of lumbar supports or education in the primary prevention of low back pain at the workplace. There is limited evidence for the efficacy of exercise, and the effect that can be obtained is moderate. There is still a need for methodologically sound studies and studies on the cost-effectiveness of exercise. Also the possible effect of lumbar supports in the treatment of back pain needs further investigation.

Design of an integrated airframe/propulsion control system architecture

NASA Technical Reports Server (NTRS)

Cohen, Gerald C.; Lee, C. William; Strickland, Michael J.; Torkelson, Thomas C.

1990-01-01

The design of an integrated airframe/propulsion control system architecture is described. The design is based on a prevalidation methodology that uses both reliability and performance. A detailed account is given for the testing associated with a subset of the architecture and concludes with general observations of applying the methodology to the architecture.

Design of experiments enhanced statistical process control for wind tunnel check standard testing

NASA Astrophysics Data System (ADS)

Phillips, Ben D.

The current wind tunnel check standard testing program at NASA Langley Research Center is focused on increasing data quality, uncertainty quantification and overall control and improvement of wind tunnel measurement processes. The statistical process control (SPC) methodology employed in the check standard testing program allows for the tracking of variations in measurements over time as well as an overall assessment of facility health. While the SPC approach can and does provide researchers with valuable information, it has certain limitations in the areas of process improvement and uncertainty quantification. It is thought by utilizing design of experiments methodology in conjunction with the current SPC practices that one can efficiently and more robustly characterize uncertainties and develop enhanced process improvement procedures. In this research, methodologies were developed to generate regression models for wind tunnel calibration coefficients, balance force coefficients and wind tunnel flow angularities. The coefficients of these regression models were then tracked in statistical process control charts, giving a higher level of understanding of the processes. The methodology outlined is sufficiently generic such that this research can be applicable to any wind tunnel check standard testing program.

Command and Control for Distributed Lethality

DTIC Science & Technology

2017-06-01

based systems engineering (MBSE) approach to C2 within the distributed lethality environment requires development of methodologies to provide...lethality environment requires development of methodologies to provide definition and structure for existing operational concepts while providing...2  D.  SCOPE AND METHODOLOGY ............................................................2  E.  STAKEHOLDER ANALYSIS

Distal biceps brachii tendon repair: a systematic review of patient outcome determination using modified Coleman methodology score criteria.

PubMed

Nyland, John; Causey, Brandon; Wera, Jeff; Krupp, Ryan; Tate, David; Gupta, Amit

2017-07-01

This systematic literature review evaluated the methodological research design quality of studies that evaluated patient outcomes following distal biceps brachii tendon repair and developed evidence-based recommendations for future patient clinical outcomes research. Following the preferred reporting items for systematic reviews and meta-analyses criteria, and using "biceps brachii", "tendon", "repair" and "outcome assessment" search terms, the CINAHL, Academic Search Premier and MEDLINE databases were searched from January 1960-October 2015. The modified Coleman methodology score (MCMS) served as the primary outcome measure. Descriptive statistical analysis was performed for composite and component MCMS and for patient outcome assessment methodology use frequency. A total of 93 studies were evaluated. Overall MCMS was low (57.1 ± 14). Only 12 (12.9 %) had prospective cohort or randomized controlled trial designs. There was a moderate relationship between publication year and MCMS (r = 0.53, P < 0.0001). Although 61 studies (65.6 %) had adequate surgical descriptions, only 3 (3.2 %) had well-described rehabilitation. Of 2253 subjects, only 39 (1.7 %) were women. Studies published after 2008 had higher MCMS scores than studies published earlier (61.3 ± 10 versus 52.9 ± 16, P = 0.003). Although overall research study methodological scores improved on average since 2008, generally low MCMS scores, retrospective designs, lack of eccentric elbow flexor or supinator strength testing, and poorly described surgical and rehabilitation descriptions remain commonplace. These findings decrease clinical study validity and generalizability. III.

21st Century Cognitive Behavioural Therapy for Anger: A Systematic Review of Research Design, Methodology and Outcome.

PubMed

Fernandez, Ephrem; Malvaso, Catia; Day, Andrew; Guharajan, Deepan

2018-07-01

Past reviews of cognitive behavioural therapy (CBT) for anger have focused on outcome in specific subpopulations, with few questions posed about research design and methodology. Since the turn of the century, there has been a surge of methodologically varied studies awaiting systematic review. The basic aim was to review this recent literature in terms of trends and patterns in research design, operationalization of anger, and covariates such as social desirability bias (SDB). Also of interest was clinical outcome. After successive culling, 42 relevant studies were retained. These were subjected to a rapid evidence assessment (REA) with special attention to design (ranked on the Scientific Methods Scale) measurement methodology (self-monitored behaviour, anger questionnaires, and others' ratings), SDB assessment, and statistical versus clinical significance. The randomized controlled trial characterized 60% of the studies, and the State Trait Anger Expression Inventory was the dominant measure of anger. All but one of the studies reported statistically significant outcome, and all but one of the 21 studies evaluating clinical significance laid claim to it. The one study with neither statistical nor clinical significance was the only one that had assessed and corrected for SDB. Measures remain relatively narrow in scope, but study designs have improved, and the outcomes suggest efficacy and clinical effectiveness. In conjunction with previous findings of an inverse relationship between anger and SDB, the results raise the possibility that the favourable picture of CBT for anger may need closer scrutiny with SDB and other methodological details in mind.

Bilateral force reflection for teleoperators with masters and slaves with dissimilar and possibly redundant kinematics

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

Jansen, J.F.; Babcock, S.M.

1989-11-01

Several bilateral control techniques and methods for exploiting redundant slaves are investigated as a part of research to develop and analyze bilateral, force-reflecting control methodologies for teleoperator systems with kinematic dissimilar masters and slaves. The study indicates that, with force/torque sensing at the wrist, and an impedance type of controller with the appropriate joint compensation, a significant improvement in performance and controllability of a teleoperator system can be achieved. 32 refs., 6 figs., 2 tabs.

Statins and tendinopathy: a systematic review.

PubMed

Teichtahl, Andrew J; Brady, Sharmayne R E; Urquhart, Donna M; Wluka, Anita E; Wang, Yuanyuan; Shaw, Jonathan E; Cicuttini, Flavia M

2016-02-15

To systematically review the evidence on whether statin therapy, commonly used in clinical practice to treat hypercholesterolaemia for primary and secondary prevention of cardiovascular disease, contributes to tendinopathy; and to examine causality according to the Bradford Hill criteria. A systematic review of studies examining the relationship between statin therapy and tendinopathy. Included studies were rated based on their methodological quality. A best evidence synthesis was used to summarise the results, and Bradford Hill criteria were used to assess causation. Ovid MEDLINE, CINAHL Plus, PubMed and Embase databases. We included adult human studies published in the English language between January 1966 and October 2015. Study designs eligible for inclusion were randomised controlled trials and cross-sectional, cohort or case-control studies. Four studies (three cohort studies and one case-control study) were included, with a mean methodological quality score of 67%. Three studies were deemed high quality. Tendon rupture was the primary outcome in three studies, and rotator cuff disease in the other. All studies found no positive association between statin therapy and tendon rupture for the total study population. There was evidence that simvastatin reduces the risk of tendinopathy. To date, there is a paucity of evidence to implicate statin therapy as a well established risk factor or causal mechanism for tendon rupture in the general population. There is strong evidence that simvastatin reduces the risk of tendinopathy.

Design, Implementation, and Operational Methodologies for Sub-arcsecond Attitude Determination, Control, and Stabilization of the Super-pressure Balloon-Borne Imaging Telescope (SuperBIT)

NASA Astrophysics Data System (ADS)

Javier Romualdez, Luis

Scientific balloon-borne instrumentation offers an attractive, competitive, and effective alternative to space-borne missions when considering the overall scope, cost, and development timescale required to design and launch scientific instruments. In particular, the balloon-borne environment provides a near-space regime that is suitable for a number of modern astronomical and cosmological experiments, where the atmospheric interference suffered by ground-based instrumentation is negligible at stratospheric altitudes. This work is centered around the analytical strategies and implementation considerations for the attitude determination and control of SuperBIT, a scientific balloon-borne payload capable of meeting the strict sub-arcsecond pointing and image stability requirements demanded by modern cosmological experiments. Broadly speaking, the designed stability specifications of SuperBIT coupled with its observational efficiency, image quality, and accessibility rivals state-of-the-art astronomical observatories such as the Hubble Space Telescope. To this end, this work presents an end-to-end design methodology for precision pointing balloon-borne payloads such as SuperBIT within an analytical yet implementationally grounded context. Simulation models of SuperBIT are analytically derived to aid in pre-assembly trade-off and case studies that are pertinent to the dynamic balloon-borne environment. From these results, state estimation techniques and control methodologies are extensively developed, leveraging the analytical framework of simulation models and design studies. This pre-assembly design phase is physically validated during assembly, integration, and testing through implementation in real-time hardware and software, which bridges the gap between analytical results and practical application. SuperBIT attitude determination and control is demonstrated throughout two engineering test flights that verify pointing and image stability requirements in flight, where the post-flight results close the overall design loop by suggesting practical improvements to pre-design methodologies. Overall, the analytical and practical results presented in this work, though centered around the SuperBIT project, provide generically useful and implementationally viable methodologies for high precision balloon-borne instrumentation, all of which are validated, justified, and improved both theoretically and practically. As such, the continuing development of SuperBIT, built from the work presented in this thesis, strives to further the potential for scientific balloon-borne astronomy in the near future.

An Investigation of Experiment Designs for Applications in Biofeedback-Performance Research Methodologies.

DTIC Science & Technology

1980-09-01

used to accomplish the necessary research . One such experi- ment design and its relationship to validity will be explored next. Nonequivalent Control ...interpreting the results. The non- equivalent control group design is of the quasi-experimental variety and is widely used in educational research . As...biofeed- back research literature is the controlled group outcome study. This design has also been discussed in Chapter III in two forms as the

Obesity in Adults with Down Syndrome: A Case-Control Study

ERIC Educational Resources Information Center

Melville, C. A.; Cooper, S.-A.; McGrother, C. W.; Thorp, C. F.; Collacott, R.

2005-01-01

Obesity has a negative impact upon mortality and morbidity. Studies report that obesity is more prevalent in individuals with Down syndrome than individuals with intellectual disabilities (ID) not associated with Down syndrome. However, there have been no studies using a methodology of matched comparison groups and findings from previous studies…

Learning Communities, Academic Performance, Attrition, and Retention: A Four-Year Study

ERIC Educational Resources Information Center

Popiolek, Gene; Fine, Ricka; Eilman, Valerie

2013-01-01

This study extends and makes unique methodological contributions to research on the impact of learning communities (LCs) on community college students. Much of the previous research was short-term, lacked adequate comparison groups, and focused on four-year college students. This four-year study controlled for instructor-related variables by…

Time Perception in Severe Traumatic Brain Injury Patients: A Study Comparing Different Methodologies

ERIC Educational Resources Information Center

Mioni, G.; Mattalia, G.; Stablum, F.

2013-01-01

In this study, we investigated time perception in patients with traumatic brain injury (TBI). Fifteen TBI patients and 15 matched healthy controls participated in the study. Participants were tested with durations above and below 1s on three different temporal tasks that involved time reproduction, production, and discrimination tasks. Data…

What Is the Efficacy of Teaching Psychotherapy to Psychiatry Residents and Medical Students?

PubMed

Truong, Anh; Wu, Peter; Diez-Barroso, Ramon; Coverdale, John

2015-10-01

Because there are no formal reviews, the authors set out to identify and evaluate studies on teaching psychotherapy to psychiatry residents and medical students. PubMed, Embase, and PsycINFO were searched for papers with outcomes on teaching psychotherapy. Search terms included psychotherapy, teaching, residents, medical students, supportive, psychodynamic, cognitive, behavioral, learning, training, skills, competency, and mentalization. Nine studies were found that met inclusion criteria. There were seven studies of psychiatry residents and two of medical students. Only two of the research designs had comparison groups, and these were both randomized controlled trials, while seven of the other designs were pretest and posttest. Teaching methods, course content, and outcome measures varied widely across studies. Common methodological problems included a lack of control, low numbers of subjects as learners, and a lack of validity of the outcome measures. Only one of the studies was judged to be methodologically rigorous. These findings establish a priority for undertaking additional rigorously designed studies in evaluating the teaching of psychotherapy to psychiatry residents and medical students.

Evaluation of glucose controllers in virtual environment: methodology and sample application.

PubMed

Chassin, Ludovic J; Wilinska, Malgorzata E; Hovorka, Roman

2004-11-01

Adaptive systems to deliver medical treatment in humans are safety-critical systems and require particular care in both the testing and the evaluation phase, which are time-consuming, costly, and confounded by ethical issues. The objective of the present work is to develop a methodology to test glucose controllers of an artificial pancreas in a simulated (virtual) environment. A virtual environment comprising a model of the carbohydrate metabolism and models of the insulin pump and the glucose sensor is employed to simulate individual glucose excursions in subjects with type 1 diabetes. The performance of the control algorithm within the virtual environment is evaluated by considering treatment and operational scenarios. The developed methodology includes two dimensions: testing in relation to specific life style conditions, i.e. fasting, post-prandial, and life style (metabolic) disturbances; and testing in relation to various operating conditions, i.e. expected operating conditions, adverse operating conditions, and system failure. We define safety and efficacy criteria and describe the measures to be taken prior to clinical testing. The use of the methodology is exemplified by tuning and evaluating a model predictive glucose controller being developed for a wearable artificial pancreas focused on fasting conditions. Our methodology to test glucose controllers in a virtual environment is instrumental in anticipating the results of real clinical tests for different physiological conditions and for different operating conditions. The thorough testing in the virtual environment reduces costs and speeds up the development process.

Controlling allosteric networks in proteins

NASA Astrophysics Data System (ADS)

Dokholyan, Nikolay

2013-03-01

We present a novel methodology based on graph theory and discrete molecular dynamics simulations for delineating allosteric pathways in proteins. We use this methodology to uncover the structural mechanisms responsible for coupling of distal sites on proteins and utilize it for allosteric modulation of proteins. We will present examples where inference of allosteric networks and its rewiring allows us to ``rescue'' cystic fibrosis transmembrane conductance regulator (CFTR), a protein associated with fatal genetic disease cystic fibrosis. We also use our methodology to control protein function allosterically. We design a novel protein domain that can be inserted into identified allosteric site of target protein. Using a drug that binds to our domain, we alter the function of the target protein. We successfully tested this methodology in vitro, in living cells and in zebrafish. We further demonstrate transferability of our allosteric modulation methodology to other systems and extend it to become ligh-activatable.

A self-contained, automated methodology for optimal flow control validated for transition delay

NASA Technical Reports Server (NTRS)

Joslin, Ronald D.; Gunzburger, Max D.; Nicolaides, R. A.; Erlebacher, Gordon; Hussaini, M. Yousuff

1995-01-01

This paper describes a self-contained, automated methodology for flow control along with a validation of the methodology for the problem of boundary layer instability suppression. The objective of control is to match the stress vector along a portion of the boundary to a given vector; instability suppression is achieved by choosing the given vector to be that of a steady base flow, e.g., Blasius boundary layer. Control is effected through the injection or suction of fluid through a single orifice on the boundary. The present approach couples the time-dependent Navier-Stokes system with an adjoint Navier-Stokes system and optimality conditions from which optimal states, i.e., unsteady flow fields, and control, e.g., actuators, may be determined. The results demonstrate that instability suppression can be achieved without any a priori knowledge of the disturbance, which is significant because other control techniques have required some knowledge of the flow unsteadiness such as frequencies, instability type, etc.

Effectiveness and safety of acupuncture in the treatment of Parkinson's disease: A systematic review and meta-analysis of randomized controlled trials.

PubMed

Noh, Hyeonseok; Kwon, Seungwon; Cho, Seung-Yeon; Jung, Woo-Sang; Moon, Sang-Kwan; Park, Jung-Mi; Ko, Chang-Nam; Park, Seong-Uk

2017-10-01

This study aimed to examine the effectiveness and safety of acupuncture in the treatment of Parkinson's disease (PD). English, Chinese, and Korean electronic databases were searched up to June 2016. Randomized controlled trials (RCTs) were eligible. The methodological quality was assessed using Cochrane's risk of bias tool. Meta-analysis was performed using RevMan 5.3. In total, 42 studies involving 2625 participants were systematically reviewed. Participants treated using combined acupuncture and conventional medication (CM) showed significant improvements in total Unified PD Rating Scale (UPDRS), UPDRS I, UPDRS II, UPDRS III, and the Webster scale compared to those treated using CM alone. The combination of electroacupuncture and CM was significantly superior to CM alone in total UPDRS, UPDRS I, UPDRS II, and UPDRS IV. Similarly, the combination of scalp electroacupuncture, acupuncture, and CM was significantly more effective than CM alone in total UPDRS. However, our meta-analysis showed that the combination of electroacupuncture and CM was not significantly more effective than CM alone in UPDRS III, the Webster, and the Tension Assessment Scale. The results also failed to show that acupuncture was significantly more effective than placebo acupuncture in total UPDRS. Overall, the methodological quality of the RCTs was low. No serious adverse events were reported. We found that acupuncture might be a safe and useful adjunctive treatment for patients with PD. However, because of methodological flaws in the included studies, conclusive evidence is still lacking. More rigorous and well-designed placebo-controlled trials should be conducted. Copyright © 2017 Elsevier Ltd. All rights reserved.

The efficacy of hypnosis as an intervention for labor and delivery pain: a comprehensive methodological review.

PubMed

Landolt, Alison S; Milling, Leonard S

2011-08-01

This paper presents a comprehensive methodological review of research on the efficacy of hypnosis for reducing labor and delivery pain. To be included, studies were required to use a between-subjects or mixed model design in which hypnosis was compared with a control condition or alternative intervention in reducing labor pain. An exhaustive search of the PsycINFO and PubMed databases produced 13 studies satisfying these criteria. Hetero-hypnosis and self-hypnosis were consistently shown to be more effective than standard medical care, supportive counseling, and childbirth education classes in reducing pain. Other benefits included better infant Apgar scores and shorter Stage 1 labor. Common methodological limitations of the literature include a failure to use random assignment, to specify the demographic characteristics of samples, and to use a treatment manual. Copyright © 2011 Elsevier Ltd. All rights reserved.

Biochemical markers of bone turnover in diabetes patients--a meta-analysis, and a methodological study on the effects of glucose on bone markers.

PubMed

Starup-Linde, J; Eriksen, S A; Lykkeboe, S; Handberg, A; Vestergaard, P

2014-06-01

This study examined whether markers of bone turnover differ between individuals with and without diabetes. Bone markers showed heterogeneity between studies and were discrepant for markers of bone creation and markers of bone degradation. Bone markers may be of lesser value in diabetes due to heterogeneity. The aim of this meta-analysis was to compare existing literature regarding changes in bone markers among diabetics compared to healthy controls. To exclude that blood glucose levels among diabetes patients could influence the assays used for determining bone turnover markers, a methodological study was performed. Medline at Pubmed Embase, Cinahl, Svemed+, Cochrane library, and Bibliotek.dk was searched in August 2012. The studies should examine biochemical bone turnover among diabetes patients in comparison to controls in an observational design. In the methodological study, fasting blood samples were drawn from two individuals. Glucose was added to the blood samples in different concentrations and OC, CTX, and procollagen type 1 amino terminal propeptide were measured after 0, 1, 2, and 3 h. Twenty-two papers fulfilled the criteria for the meta-analysis. From the pooled data in the meta-analysis, the bone markers osteocalcin (OC) (-1.15 ng/ml [-1.78,-0.52]) and C-terminal cross-linked telopeptide (CTX) (-0.14 ng/ml [-0.22, -0.05]) were significantly lower among diabetes patients than non-diabetes patients, however other markers did not differ. All markers displayed very high heterogeneity by I2 statistics. In the methodological study, the addition of glucose did not significantly change the bone markers neither by level of glucose nor with increasing incubation time. The dissociative pattern of biochemical bone markers of bone formation and bone resorption present in diabetes patients is thus not caused by glucose per se but may be modulated by unknown factors associated with diabetes mellitus.

Hybrid time-variant reliability estimation for active control structures under aleatory and epistemic uncertainties

NASA Astrophysics Data System (ADS)

Wang, Lei; Xiong, Chuang; Wang, Xiaojun; Li, Yunlong; Xu, Menghui

2018-04-01

Considering that multi-source uncertainties from inherent nature as well as the external environment are unavoidable and severely affect the controller performance, the dynamic safety assessment with high confidence is of great significance for scientists and engineers. In view of this, the uncertainty quantification analysis and time-variant reliability estimation corresponding to the closed-loop control problems are conducted in this study under a mixture of random, interval, and convex uncertainties. By combining the state-space transformation and the natural set expansion, the boundary laws of controlled response histories are first confirmed with specific implementation of random items. For nonlinear cases, the collocation set methodology and fourth Rounge-Kutta algorithm are introduced as well. Enlightened by the first-passage model in random process theory as well as by the static probabilistic reliability ideas, a new definition of the hybrid time-variant reliability measurement is provided for the vibration control systems and the related solution details are further expounded. Two engineering examples are eventually presented to demonstrate the validity and applicability of the methodology developed.

Comparison between exclusively school teacher-based and mixed school teacher and healthcare provider-based programme on basic cardiopulmonary resuscitation for secondary schools.

PubMed

Jiménez-Fábrega, X; Escalada-Roig, X; Miró, O; Sanclemente, G; Díaz, N; Gómez, X; Villena, O; Rodríguez, E; Gaspar, A; Molina, J E; Salvador, J; Sánchez, M

2009-09-01

To compare two teaching methodologies for PROCES (a basic cardiopulmonary resuscitation (b-CPR) programme for secondary school students): one exclusively performed by school teachers (study group) and another by a mixed team of school teachers and healthcare providers (control group). According to their preferences, teachers chose either method and students were consequently assigned to the control or study group. All participants took a 10 multiple-choice question exam regarding b-CPR skills twice: immediately after PROCES and one year later. Eight or more correct answers was considered satisfactory learning. Results between groups were compared. Associations between satisfactory learning and some student characteristics were analysed. Immediately after PROCES, 442 students (219 in the study group and 223 in the control group) took the exam. The percentage of satisfactory learning was not different: 67.1% in the study group and 64.6% in the control group. Immediate satisfactory learning was related to the absence of pending subjects in the control (odds ratio (OR) 2.31, 95% CI 1.16 to 4.64) and study (OR 5.87, 95% CI 1.22 to 28.20) groups. One year later, a greater percentage of retention of b-CRP skills was detected in the study group (57.1% vs 40.6%; p = 0.01). The absence of any pending subject (OR 6.86, 95% CI 1.83 to 25.66) was independently associated with better retention in the study group, but not the control group. Secondary school teachers, previously trained in b-CPR, can teach these skills effectively to 14-16-year-old students using PROCES. The retention of b-CPR skills is greater with this methodology compared with a more standardised programme.

Sectorized psychiatry. A methodological study of the effects of reorganization on patients treated at a mental hospital.

PubMed

Lindholm, H

1983-01-01

The aim of the study was to find relevant methods and use them to investigate the effects of sectorized psychiatry on former mental hospital patients. Seventeen hypotheses were formulated, concerning both positive and negative effects of sectorized psychiatry. Relevance and expected availability decided the variables, which were based on information from medical registers, case records, death certificates, social authorities, courts of law, public health insurance, census office and personal interviews. The hypotheses were tested by the use of two groups of patients, 377 in one experimental group, and 377 in one control group. A matched control method was used. The study patients were domiciled in the catchment area for the first complete trial of sectorized psychiatric service in the Stockholm area. The control patients were domiciled in the catchment area for the remaining divisions of Beckomberga Mental Hospital. During the actual years, an experimental situation was at hand. Comparisons in each pair were performed, regarding the experimental year 1980. A methodological description of variables for measurement of the effects and changes in psychiatric care is presented. The comparison showed no significant differences in the analyses, regarding utilization of inpatient care at Beckomberga Hospital in 1980. Study patients had significantly more outpatient visits and day-care days compared to controls. Study patients reported significantly shorter time of public transportation between home and psychiatric service. Study patients were significantly more often discharged to the division's own agencies compared to controls. Study patients reported significantly less satisfaction with ward staff than controls. No significant differences in direct cost of treatment during the experimental year were registered. The conclusion is, that there are no consistent tendencies proving the new organization superior to the traditional one for these former mental hospital patients.

Adverse effects of psychosocial work factors on blood pressure: systematic review of studies on demand-control-support and effort-reward imbalance models.

PubMed

Gilbert-Ouimet, Mahée; Trudel, Xavier; Brisson, Chantal; Milot, Alain; Vézina, Michel

2014-03-01

A growing body of research has investigated the adverse effects of psychosocial work factors on blood pressure (BP) elevation. There is now a clear need for an up-to-date, critical synthesis of reliable findings on this topic. This systematic review aimed to evaluate the adverse effects of psychosocial work factors of both the demand-control-support (DCS) and effort-reward imbalance (ERI) models on BP among men and women, according to the methodological quality of the studies. To be eligible, studies had to: (i) evaluate at least one psychosocial work factor, (ii) evaluate BP or hypertension, (iii) comprise ≥100 workers, (iv) be written in English or French, and (v) be published in a peer-reviewed journal. A total of 74 studies were included. Of these, 64 examined the DCS model, and 12 looked at the ERI model, with 2 studies considering both models. Approximately half the studies observed a significant adverse effect of psychosocial work factors on BP. A more consistent effect was observed, however, among men than women. For job strain, a more consistent effect was also observed in studies of higher methodological quality, ie, studies using a prospective design and ambulatory BP measures. A more consistent adverse effect of psychosocial work factors was observed among men than women and in studies of higher methodological quality. These findings contribute to the current effort of primary prevention of cardiovascular disease by documenting the psychosocial etiology of elevated BP, a major cardiovascular risk factor.

A systematic review of controlled clinical trials on the prevention of back pain in industry.

PubMed

van Poppel, M N; Koes, B W; Smid, T; Bouter, L M

1997-12-01

To assess the effectiveness of lumbar supports, education, and exercise in the prevention of back pain in industry. A computerised search for controlled clinical trials was conducted. A criteria list was used to assess the methodological quality of the studies. The available evidence for the effectiveness of the interventions was graded with a rating system for the level of evidence. Effect sizes of individual studies were combined if the studies were sufficiently similar. 11 studies were identified for the review. The methodological quality of all studies was low, with a maximum score of three out of seven for internal validity. There was no evidence for the effectiveness of lumbar supports due to contradictory outcomes of the studies. Five of the six studies on education reported no effect. Thus there is limited evidence that education does not help to prevent back pain. All three studies on exercise reported a positive result, indicating limited evidence for the effectiveness of exercise. The combined effect size for exercise was 0.53, which is a medium sized effect. Although widely used, there is little evaluative research on the preventive measures studied here. The review showed that there is limited evidence that exercise has some effect in the prevention of back pain and that education is not effective. No conclusive evidence was found for or against the effectiveness of lumbar supports. Research of higher methodological quality is needed before firm conclusions on the effectiveness of lumbar supports, education, and exercise in the prevention of back pain in industry can be drawn.

Research Methods in Healthcare Epidemiology and Antimicrobial Stewardship-Mathematical Modeling.

PubMed

Barnes, Sean L; Kasaie, Parastu; Anderson, Deverick J; Rubin, Michael

2016-11-01

Mathematical modeling is a valuable methodology used to study healthcare epidemiology and antimicrobial stewardship, particularly when more traditional study approaches are infeasible, unethical, costly, or time consuming. We focus on 2 of the most common types of mathematical modeling, namely compartmental modeling and agent-based modeling, which provide important advantages-such as shorter developmental timelines and opportunities for extensive experimentation-over observational and experimental approaches. We summarize these advantages and disadvantages via specific examples and highlight recent advances in the methodology. A checklist is provided to serve as a guideline in the development of mathematical models in healthcare epidemiology and antimicrobial stewardship. Infect Control Hosp Epidemiol 2016;1-7.

A Qualitative Study to Improve the Student Learning Experience

ERIC Educational Resources Information Center

Jastania, Raid A.; Balata, Gehan F.; Abd El-Hady, Mohamed I. S.; Gouda, Ahmad; Abd El-Wahab, Mohamad; Mohamad, Abeer S.; Ibrahim, Nashwa M.; Beshr, Eman; Mahdi, Abeer Y.; Mousa, Rabab; Tag, Batool F.; Hisham, Hadeel; El-Sofiani, Ibtehal

2017-01-01

Purpose: For any educational institution, student satisfaction is an important goal. Thus, the purpose of the study is to use a structured improvement process, define--measure--analyse--improve--control (DMAIC) methodology, to improve students' satisfaction regarding their learning experience at the College of Pharmacy/Umm Al-Qura University.…

An Improvement in Instructional Quality: Can Evaluation of Teaching Effectiveness Make a Difference?

ERIC Educational Resources Information Center

Ngware, Moses Waithanji; Ndirangu, Mwangi

2005-01-01

Purpose: To report study findings on teaching effectiveness and feedback mechanisms in Kenyan universities, which can guide management in developing a comprehensive quality control policy. Design/methodology/approach: The study adopted an exploratory descriptive design. Three public and two private universities were randomly selected to…

21 CFR 114.90 - Methodology.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Methodology. 114.90 Section 114.90 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION ACIDIFIED FOODS Production and Process Controls § 114.90 Methodology. Methods that may be used to...

21 CFR 114.90 - Methodology.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Methodology. 114.90 Section 114.90 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION ACIDIFIED FOODS Production and Process Controls § 114.90 Methodology. Methods that may be used to...

21 CFR 114.90 - Methodology.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Methodology. 114.90 Section 114.90 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION ACIDIFIED FOODS Production and Process Controls § 114.90 Methodology. Methods that may be used to...

"Assessing the methodological quality of systematic reviews in radiation oncology: A systematic review".

PubMed

Hasan, Haroon; Muhammed, Taaha; Yu, Jennifer; Taguchi, Kelsi; Samargandi, Osama A; Howard, A Fuchsia; Lo, Andrea C; Olson, Robert; Goddard, Karen

2017-10-01

The objective of our study was to evaluate the methodological quality of systematic reviews and meta-analyses in Radiation Oncology. A systematic literature search was conducted for all eligible systematic reviews and meta-analyses in Radiation Oncology from 1966 to 2015. Methodological characteristics were abstracted from all works that satisfied the inclusion criteria and quality was assessed using the critical appraisal tool, AMSTAR. Regression analyses were performed to determine factors associated with a higher score of quality. Following exclusion based on a priori criteria, 410 studies (157 systematic reviews and 253 meta-analyses) satisfied the inclusion criteria. Meta-analyses were found to be of fair to good quality while systematic reviews were found to be of less than fair quality. Factors associated with higher scores of quality in the multivariable analysis were including primary studies consisting of randomized control trials, performing a meta-analysis, and applying a recommended guideline related to establishing a systematic review protocol and/or reporting. Systematic reviews and meta-analyses may introduce a high risk of bias if applied to inform decision-making based on AMSTAR. We recommend that decision-makers in Radiation Oncology scrutinize the methodological quality of systematic reviews and meta-analyses prior to assessing their utility to inform evidence-based medicine and researchers adhere to methodological standards outlined in validated guidelines when embarking on a systematic review. Copyright © 2017 Elsevier Ltd. All rights reserved.

Does Sexy Media Promote Teen Sex? A Meta-Analytic and Methodological Review.

PubMed

Ferguson, Christopher J; Nielsen, Rune K L; Markey, Patrick M

2017-06-01

Parents and policy makers are often concerned that sexy media (media depicting or discussing sexual encounters) may promote sexual behavior in young viewers. There has been some debate among scholars regarding whether such media promote sexual behaviors. It remains unclear to what extent sexy media is a risk factor for increased sexual behavior among youth. The current study employed a meta-analysis of 22 correlational and longitudinal studies of sexy media effects on teen sexual behavior (n = 22,172). Moderator analyses examined methodological and science culture issues such as citation bias. Results indicated the presence only of very weak effects. General media use did not correlate with sexual behaviors (r = 0.005), and sexy media use correlated only weakly with sexual behaviors (r = 0.082) once other factors had been controlled. Higher effects were seen for studies with citation bias, and lower effects when family environment is controlled. The impact of media on teen sexuality was minimal with effect sizes near to zero.

Effectiveness of clinical pathways for total knee and total hip arthroplasty: literature review.

PubMed

Kim, Stephen; Losina, Elena; Solomon, Daniel H; Wright, John; Katz, Jeffrey N

2003-01-01

Although many hospitals have implemented clinical pathways to standardize the process of care, the effectiveness of clinical pathways for total hip and knee arthroplasties has not been reviewed critically. We searched for articles comparing outcomes of total hip or knee arthroplasty for patients who were treated using clinical pathways as opposed to patients treated without these pathways. Eleven studies met criteria for inclusion. Ten used historical controls, and 1 was a randomized trial. The studies had important methodological limitations. In general, the articles showed that patients treated using pathways experienced shorter hospital stays and lower costs, with comparable clinical outcomes as compared with patients treated without clinical pathways. We concluded that clinical pathways appear successful in reducing costs and length of stay in the acute care hospital, with no compromise in patient outcomes. However, interpretation of these studies is complicated by substantial methodological limitations, particularly the use of historical controls and failure to account for length of stay in rehabilitation facilities. Copyright 2003, Elsevier Science (USA). All rights reserved.

Return to Baseline: Some Comments on Smith's Reinterpretation of Seclusionary Timeout.

ERIC Educational Resources Information Center

Polsgrove, Lewis

1982-01-01

The author replies to an earlier contention of D. Smith (EC 133 830) that seclusionary timeout for behavior disordered children actually constitutes extinction rather than aversive control. The author cites methodological flaws in Smith's studies. (CL)

Designing low cost LED display for the billboard

NASA Astrophysics Data System (ADS)

Hong, Yi-Jian; Uang, Chii-Maw; Wang, Ping-Chieh; Ho, Zu-Sheng

2011-10-01

With quickly advance of the computer, microelectronics and photonics technologies, LED display panel becomes a new electronic advertising media. It can be used to show any information whatever characters or graphics. Most LED display panels are built of many Light-Emitting Diodes arranged in a matrix form. The display has many advantages such as low power, low cost, long life and high definition. Because the display panel is asked to show rich color, the LED display panel's driving system becomes very complex. The design methodology of LED display panel's driver becomes more and more important to meet the market requirements. Cost is always the most important issue in public market domain. In this paper, we report a design methodology of LED display panel's driver based on the microprocessor control unit (MCU) system and LED display controller IC, HT1632C, to control three colors, RGB, color LED display panel and the modular panel size is 24*16 in matrix form. The HT1632C is a memory mapping LED display controller, it can be used on many applications, such as digital clock, thermometer, counter, voltmeter or other instrumentation readouts. Three pieces of HT1632C are used to drive a 24*16 RGB LED display panel, in our design case. Each HT163C chip is used to control one of the R, G and B color. As the drive mode is driven in DC mode, the RGB display panel can create and totally of seven colors under the control of MCU. The MCU generates the control signal to drive HT1632C. In this study, the software design methodology is adopted with dynamic display principle. When the scan frequency is 60Hz, LED display panel will get the clear picture and be able to display seven colors.

Performance evaluation of contrast-detail in full field digital mammography systems using ideal (Hotelling) observer vs. conventional automated analysis of CDMAM images for quality control of contrast-detail characteristics.

PubMed

Delakis, Ioannis; Wise, Robert; Morris, Lauren; Kulama, Eugenia

2015-11-01

The purpose of this work was to evaluate the contrast-detail performance of full field digital mammography (FFDM) systems using ideal (Hotelling) observer Signal-to-Noise Ratio (SNR) methodology and ascertain whether it can be considered an alternative to the conventional, automated analysis of CDMAM phantom images. Five FFDM units currently used in the national breast screening programme were evaluated, which differed with respect to age, detector, Automatic Exposure Control (AEC) and target/filter combination. Contrast-detail performance was analysed using CDMAM and ideal observer SNR methodology. The ideal observer SNR was calculated for input signal originating from gold discs of varying thicknesses and diameters, and then used to estimate the threshold gold thickness for each diameter as per CDMAM analysis. The variability of both methods and the dependence of CDMAM analysis on phantom manufacturing discrepancies also investigated. Results from both CDMAM and ideal observer methodologies were informative differentiators of FFDM systems' contrast-detail performance, displaying comparable patterns with respect to the FFDM systems' type and age. CDMAM results suggested higher threshold gold thickness values compared with the ideal observer methodology, especially for small-diameter details, which can be attributed to the behaviour of the CDMAM phantom used in this study. In addition, ideal observer methodology results showed lower variability than CDMAM results. The Ideal observer SNR methodology can provide a useful metric of the FFDM systems' contrast detail characteristics and could be considered a surrogate for conventional, automated analysis of CDMAM images. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Methods for Evaluating Natural Experiments in Obesity: A Systematic Review.

PubMed

Bennett, Wendy L; Wilson, Renee F; Zhang, Allen; Tseng, Eva; Knapp, Emily A; Kharrazi, Hadi; Stuart, Elizabeth A; Shogbesan, Oluwaseun; Bass, Eric B; Cheskin, Lawrence J

2018-06-05

Given the obesity pandemic, rigorous methodological approaches, including natural experiments, are needed. To identify studies that report effects of programs, policies, or built environment changes on obesity prevention and control and to describe their methods. PubMed, CINAHL, PsycINFO, and EconLit (January 2000 to August 2017). Natural experiments and experimental studies evaluating a program, policy, or built environment change in U.S. or non-U.S. populations by using measures of obesity or obesity-related health behaviors. 2 reviewers serially extracted data on study design, population characteristics, data sources and linkages, measures, and analytic methods and independently evaluated risk of bias. 294 studies (188 U.S., 106 non-U.S.) were identified, including 156 natural experiments (53%), 118 experimental studies (40%), and 20 (7%) with unclear study design. Studies used 106 (71 U.S., 35 non-U.S.) data systems; 37% of the U.S. data systems were linked to another data source. For outcomes, 112 studies reported childhood weight and 32 adult weight; 152 had physical activity and 148 had dietary measures. For analysis, natural experiments most commonly used cross-sectional comparisons of exposed and unexposed groups (n = 55 [35%]). Most natural experiments had a high risk of bias, and 63% had weak handling of withdrawals and dropouts. Outcomes restricted to obesity measures and health behaviors; inconsistent or unclear descriptions of natural experiment designs; and imperfect methods for assessing risk of bias in natural experiments. Many methodologically diverse natural experiments and experimental studies were identified that reported effects of U.S. and non-U.S. programs, policies, or built environment changes on obesity prevention and control. The findings reinforce the need for methodological and analytic advances that would strengthen evaluations of obesity prevention and control initiatives. National Institutes of Health, Office of Disease Prevention, and Agency for Healthcare Research and Quality. (PROSPERO: CRD42017055750).

Digital redesign of anti-wind-up controller for cascaded analog system.

PubMed

Chen, Y S; Tsai, J S H; Shieh, L S; Moussighi, M M

2003-01-01

The cascaded conventional anti-wind-up (CAW) design method for integral controller is discussed. Then, the prediction-based digital redesign methodology is utilized to find the new pulse amplitude modulated (PAM) digital controller for effective digital control of the analog plant with input saturation constraint. The desired digital controller is determined from existing or pre-designed CAW analog controller. The proposed method provides a novel methodology for indirect digital design of a continuous-time unity output-feedback system with a cascaded analog controller as in the case of PID controllers for industrial control processes with the presence of actuator saturations. It enables us to implement an existing or pre-designed cascaded CAW analog controller via a digital controller effectively.

Current evidence demonstrates similar effects of kilohertz-frequency and low-frequency current on quadriceps evoked torque and discomfort in healthy individuals: a systematic review with meta-analysis.

PubMed

da Silva, Vinicius Zacarias Maldaner; Durigan, João Luiz Quaglioti; Arena, Ross; de Noronha, Marcos; Gurney, Burke; Cipriano, Gerson

2015-01-01

Neuromuscular electrical stimulation (NMES) is widely utilized to enhance muscle performance. However, the optimal NMES waveform with respect to treatment effect has not been established. To investigate the effects of kilohertz-frequency alternating current (KFAC) and low-frequency pulsed current (PC) on quadriceps evoked torque and self-reported discomfort. PubMed, The Cochrane Library, EMBASE, MEDLINE, Physiotherapy Evidence Database (PEDro), SinoMed, ISI Web of Knowledge, and CINAHL were searched for randomized controlled trials (RCTs) and quasi-randomized controlled trials (QRCTs). Two reviewers independently selected potential studies according to the inclusion criteria, extracted data, and assessed methodological quality. Studies were eligible if they compared KFAC versus PC interventions. Studies that included outcome measures for percentage of maximal isometric voluntary contraction (%MIVC) torque and self-reported discomfort level were eligible for evaluation. Seven studies involving 127 individuals were included. The methodological quality of eligible trials was moderate, with a mean of 5 on the 10-point PEDro scale. Overall, PC was no better than KFAC in terms of evoked torque and there was no difference in self-reported discomfort level. KFAC and PC have similar effects on quadriceps evoked torque and self-reported discomfort level in healthy individuals. The small number and overall methodological quality of currently available studies included in this meta-analysis indicate that new RCTs are needed to better determine optimal NMES treatment parameters.

Interventions aimed at increasing research use in nursing: a systematic review

PubMed Central

Thompson, David S; Estabrooks, Carole A; Scott-Findlay, Shannon; Moore, Katherine; Wallin, Lars

2007-01-01

Background There has been considerable interest recently in developing and evaluating interventions to increase research use by clinicians. However, most work has focused on medical practices; and nursing is not well represented in existing systematic reviews. The purpose of this article is to report findings from a systematic review of interventions aimed at increasing research use in nursing. Objective To assess the evidence on interventions aimed at increasing research use in nursing. Methods A systematic review of research use in nursing was conducted using databases (Medline, CINAHL, Healthstar, ERIC, Cochrane Central Register of Controlled Trials, and Psychinfo), grey literature, ancestry searching (Cochrane Database of Systematic Reviews), key informants, and manual searching of journals. Randomized controlled trials and controlled before- and after-studies were included if they included nurses, if the intervention was explicitly aimed at increasing research use or evidence-based practice, and if there was an explicit outcome to research use. Methodological quality was assessed using pre-existing tools. Data on interventions and outcomes were extracted and categorized using a pre-established taxonomy. Results Over 8,000 titles were screened. Three randomized controlled trials and one controlled before- and after-study met the inclusion criteria. The methodological quality of included studies was generally low. Three investigators evaluated single interventions. The most common intervention was education. Investigators measured research use using a combination of surveys (three studies) and compliance with guidelines (one study). Researcher-led educational meetings were ineffective in two studies. Educational meetings led by a local opinion leader (one study) and the formation of multidisciplinary committees (one study) were both effective at increasing research use. Conclusion Little is known about how to increase research use in nursing, and the evidence to support or refute specific interventions is inconclusive. To advance the field, we recommend that investigators: (1) use theoretically informed interventions to increase research use, (2) measure research use longitudinally using theoretically informed and psychometrically sound measures of research use, as well as, measuring patient outcomes relevant to the intervention, and (3) use more robust and methodologically sound study designs to evaluate interventions. If investigators aim to establish a link between using research and improved patient outcomes they must first identify those interventions that are effective at increasing research use. PMID:17498301

Recent Methodology in Ginseng Analysis

PubMed Central

Baek, Seung-Hoon; Bae, Ok-Nam; Park, Jeong Hill

2012-01-01

As much as the popularity of ginseng in herbal prescriptions or remedies, ginseng has become the focus of research in many scientific fields. Analytical methodologies for ginseng, referred to as ginseng analysis hereafter, have been developed for bioactive component discovery, phytochemical profiling, quality control, and pharmacokinetic studies. This review summarizes the most recent advances in ginseng analysis in the past half-decade including emerging techniques and analytical trends. Ginseng analysis includes all of the leading analytical tools and serves as a representative model for the analytical research of herbal medicines. PMID:23717112

Semantic Network Adaptation Based on QoS Pattern Recognition for Multimedia Streams

NASA Astrophysics Data System (ADS)

Exposito, Ernesto; Gineste, Mathieu; Lamolle, Myriam; Gomez, Jorge

This article proposes an ontology based pattern recognition methodology to compute and represent common QoS properties of the Application Data Units (ADU) of multimedia streams. The use of this ontology by mechanisms located at different layers of the communication architecture will allow implementing fine per-packet self-optimization of communication services regarding the actual application requirements. A case study showing how this methodology is used by error control mechanisms in the context of wireless networks is presented in order to demonstrate the feasibility and advantages of this approach.

Vitex agnus-castus extracts for female reproductive disorders: a systematic review of clinical trials.

PubMed

van Die, M Diana; Burger, Henry G; Teede, Helena J; Bone, Kerry M

2013-05-01

Vitex agnus-castus L. (chaste tree; chasteberry) is a popular herbal treatment, predominantly used for a range of female reproductive conditions in Anglo-American and European practice. The objective of this systematic review was to evaluate the evidence for the efficacy and safety of Vitex extracts from randomised, controlled trials investigating women's health.Eight databases were searched using Latin and common names for Vitex and phytotherapeutic preparations of the herb as a sole agent, together with filters for randomised, controlled trials or clinical trials. Methodological quality was assessed according to the Cochrane risk of bias and Jadad scales, as well as the proposed elaboration of CONSORT for reporting trials on herbal interventions.Thirteen randomised, controlled trials were identified and twelve are included in this review, of which eight investigated premenstrual syndrome, two premenstrual dysphoric disorder, and two latent hyperprolactinaemia. For premenstrual syndrome, seven of eight trials found Vitex extracts to be superior to placebo (5 of 6 studies), pyridoxine (1), and magnesium oxide (1). In premenstrual dysphoric disorder, one study reported Vitex to be equivalent to fluoxetine, while in the other, fluoxetine outperformed Vitex. In latent hyperprolactinaemia, one trial reported it to be superior to placebo for reducing TRH-stimulated prolactin secretion, normalising a shortened luteal phase, increasing mid-luteal progesterone and 17β-oestradiol levels, while the other found Vitex comparable to bromocriptine for reducing serum prolactin levels and ameliorating cyclic mastalgia. Adverse events with Vitex were mild and generally infrequent. The methodological quality of the included studies varied, but was generally moderate-to-high. Limitations include small sample sizes in some studies, heterogeneity of conditions being treated, and a range of reference treatments.Despite some methodological limitations, the results from randomised, controlled trials to date suggest benefits for Vitex extracts in the treatment of premenstrual syndrome, premenstrual dysphoric disorder and latent hyperprolactinaemia. Further research is recommended, and greater transparency in reporting for future trials. Georg Thieme Verlag KG Stuttgart · New York.

Application of Haddon's matrix in qualitative research methodology: an experience in burns epidemiology.

PubMed

Deljavan, Reza; Sadeghi-Bazargani, Homayoun; Fouladi, Nasrin; Arshi, Shahnam; Mohammadi, Reza

2012-01-01

Little has been done to investigate the application of injury specific qualitative research methods in the field of burn injuries. The aim of this study was to use an analytical tool (Haddon's matrix) through qualitative research methods to better understand people's perceptions about burn injuries. This study applied Haddon's matrix as a framework and an analytical tool for a qualitative research methodology in burn research. Both child and adult burn injury victims were enrolled into a qualitative study conducted using focus group discussion. Haddon's matrix was used to develop an interview guide and also through the analysis phase. The main analysis clusters were pre-event level/human (including risky behaviors, belief and cultural factors, and knowledge and education), pre-event level/object, pre-event phase/environment and event and post-event phase (including fire control, emergency scald and burn wound management, traditional remedies, medical consultation, and severity indicators). This research gave rise to results that are possibly useful both for future injury research and for designing burn injury prevention plans. Haddon's matrix is applicable in a qualitative research methodology both at data collection and data analysis phases. The study using Haddon's matrix through a qualitative research methodology yielded substantially rich information regarding burn injuries that may possibly be useful for prevention or future quantitative research.

The Beliefs, Attitudes and Views of University Students about Anger and the Effects of Cognitive Behavioral Therapy-Oriented Anger Control and Anxiety Management Programs on Their Anger Management Skill Levels

ERIC Educational Resources Information Center

Karahan, T. Fikret; Yalçin, B. Murat; Erbas, Melda M.

2014-01-01

This study was designed as a qualitative focus group using a randomized controlled trail with a mixed methodology. The study has dual aims. First we searched the beliefs, attitudes and views of 176 university students on how to deal with anger using eight focus discussion groups. The anxiety and anger levels of these students were investigated…

Job rotation designed to prevent musculoskeletal disorders and control risk in manufacturing industries: A systematic review.

PubMed

Padula, Rosimeire Simprini; Comper, Maria Luiza Caires; Sparer, Emily H; Dennerlein, Jack T

2017-01-01

To better understand job rotation in the manufacturing industry, we completed a systematic review asking the following questions: 1) How do job-rotation programs impact work-related musculoskeletal disorders (MSDs) and related risk control for these MSDs, as well as psychosocial factors? and 2) How best should the job rotation programs be designed? We searched MEDLINE, EMBASE, Business Source Premier, ISI Web of Knowledge, CINAHL, PsyINFO, Scopus, and SciELO databases for articles published in peer-reviewed journals. Eligible studies were examined by two independent reviewers for relevance (population of manufacturing workers, outcomes of musculoskeletal disorders, physical factors, psychosocial factors, and strategies used in job-rotation implantation) and methodological quality rating. From 10,809 potential articles, 71 were read for full text analysis. Of the 14 studies included for data extraction, two were non-randomized control trial studies, one was a case-control study, and 11 were cross-sectional comparisons. Only one, with a case-control design, was scored with good methodological quality. Currently, weak evidence exists supporting job rotation as a strategy for the prevention and control of musculoskeletal disorders. Job rotation did not appear to reduce the exposure of physical risk factors; yet, there are positive correlations between job rotation and higher job satisfaction. Worker training has been described as a crucial component of a successful job-rotation program. The studies reported a range of parameters used to implement and measure job-rotation programs. More rigorous studies are needed to better understand the full impact of job rotation on production and health. CRD42014013319. Copyright © 2016 Elsevier Ltd. All rights reserved.

Developpement d'une plateforme de simulation et d'un pilote automatique - Application aux Cessna Citation X et Hawker 800XP

NASA Astrophysics Data System (ADS)

Ghazi, Georges

This report presents several methodologies for the design of tools intended to the analysis of the stability and the control of a business aircraft. At first, a generic flight dynamic model was developed to predict the behavior of the aircraft further to a movement on the control surfaces or further to any disturbance. For that purpose, different categories of winds were considered in the module of simulation to generate various scenarios and conclude about the efficiency of the autopilot. Besides being realistic, the flight model takes into account the variation of the mass parameters according to fuel consumption. A comparison with a simulator of the company CAE Inc. and certified level D allowed to validate this first stage with an acceptable success rate. Once the dynamics is validated, the next stage deals with the stability around a flight condition. For that purpose, a first static analysis is established to find the trim conditions inside the flight envelop. Then, two algorithms of linearization generate the state space models which approximate the decoupled dynamics (longitudinal and lateral) of the aircraft. Then to test the viability of the linear models, 1,500 comparisons with the nonlinear dynamics have been done with a 100% rate of success. The study of stability allowed to highlight the need of control systems to improve first the performances of the plane, then to control its different axes. A methodology based on a coupling between a modern control technique (LQR) and a genetic algorithm is presented. This methodology allowed to find optimal and successful controllers which satisfy a large number of specifications. Besides being successful, they have to be robust to uncertainties owed to the variation of mass. Thus, an analysis of robustness using the theory of the guardian maps was applied to uncertain dynamics. However, because of a too sensitive region of the flight envelop, some analyses are biased. Nevertheless, a validation with the nonlinear dynamics allowed to prove the robustness of the controllers over the entire flight envelope. Finally, the last stage of this project concerned the control laws for the autopilot. Once again, the proposed methodology, bases itself on the association of flight mechanic equations, control theory and a metaheuristic optimization method. Afterward, four detailed test scenarios are presented to illustrate the efficiency and the robustness of the entire autopilot.

Methods for the guideline-based development of quality indicators--a systematic review

PubMed Central

2012-01-01

Background Quality indicators (QIs) are used in many healthcare settings to measure, compare, and improve quality of care. For the efficient development of high-quality QIs, rigorous, approved, and evidence-based development methods are needed. Clinical practice guidelines are a suitable source to derive QIs from, but no gold standard for guideline-based QI development exists. This review aims to identify, describe, and compare methodological approaches to guideline-based QI development. Methods We systematically searched medical literature databases (Medline, EMBASE, and CINAHL) and grey literature. Two researchers selected publications reporting methodological approaches to guideline-based QI development. In order to describe and compare methodological approaches used in these publications, we extracted detailed information on common steps of guideline-based QI development (topic selection, guideline selection, extraction of recommendations, QI selection, practice test, and implementation) to predesigned extraction tables. Results From 8,697 hits in the database search and several grey literature documents, we selected 48 relevant references. The studies were of heterogeneous type and quality. We found no randomized controlled trial or other studies comparing the ability of different methodological approaches to guideline-based development to generate high-quality QIs. The relevant publications featured a wide variety of methodological approaches to guideline-based QI development, especially regarding guideline selection and extraction of recommendations. Only a few studies reported patient involvement. Conclusions Further research is needed to determine which elements of the methodological approaches identified, described, and compared in this review are best suited to constitute a gold standard for guideline-based QI development. For this research, we provide a comprehensive groundwork. PMID:22436067

Mobile phone use and risk of tumors: a meta-analysis.

PubMed

Myung, Seung-Kwon; Ju, Woong; McDonnell, Diana D; Lee, Yeon Ji; Kazinets, Gene; Cheng, Chih-Tao; Moskowitz, Joel M

2009-11-20

Case-control studies have reported inconsistent findings regarding the association between mobile phone use and tumor risk. We investigated these associations using a meta-analysis. We searched MEDLINE (PubMed), EMBASE, and the Cochrane Library in August 2008. Two evaluators independently reviewed and selected articles based on predetermined selection criteria. Of 465 articles meeting our initial criteria, 23 case-control studies, which involved 37,916 participants (12,344 patient cases and 25,572 controls), were included in the final analyses. Compared with never or rarely having used a mobile phone, the odds ratio for overall use was 0.98 for malignant and benign tumors (95% CI, 0.89 to 1.07) in a random-effects meta-analysis of all 23 studies. However, a significant positive association (harmful effect) was observed in a random-effects meta-analysis of eight studies using blinding, whereas a significant negative association (protective effect) was observed in a fixed-effects meta-analysis of 15 studies not using blinding. Mobile phone use of 10 years or longer was associated with a risk of tumors in 13 studies reporting this association (odds ratio = 1.18; 95% CI, 1.04 to 1.34). Further, these findings were also observed in the subgroup analyses by methodologic quality of study. Blinding and methodologic quality of study were strongly associated with the research group. The current study found that there is possible evidence linking mobile phone use to an increased risk of tumors from a meta-analysis of low-biased case-control studies. Prospective cohort studies providing a higher level of evidence are needed.

Interest and limits of the six sigma methodology in medical laboratory.

PubMed

Scherrer, Florian; Bouilloux, Jean-Pierre; Calendini, Ors'Anton; Chamard, Didier; Cornu, François

2017-02-01

The mandatory accreditation of clinical laboratories in France provides an incentive to develop real tools to measure performance management methods and to optimize the management of internal quality controls. Six sigma methodology is an approach commonly applied to software quality management and discussed in numerous publications. This paper discusses the primary factors that influence the sigma index (the choice of the total allowable error, the approach used to address bias) and compares the performance of different analyzers on the basis of the sigma index. Six sigma strategy can be applied to the policy management of internal quality control in a laboratory and demonstrates through a comparison of four analyzers that there is no single superior analyzer in clinical chemistry. Similar sigma results are obtained using approaches toward bias based on the EQAS or the IQC. The main difficulty in using the six sigma methodology lies in the absence of official guidelines for the definition of the total error acceptable. Despite this drawback, our comparison study suggests that difficulties with defined analytes do not vary with the analyzer used.

Does Exercise Improve Cognitive Performance? A Conservative Message from Lord's Paradox.

PubMed

Liu, Sicong; Lebeau, Jean-Charles; Tenenbaum, Gershon

2016-01-01

Although extant meta-analyses support the notion that exercise results in cognitive performance enhancement, methodology shortcomings are noted among primary evidence. The present study examined relevant randomized controlled trials (RCTs) published in the past 20 years (1996-2015) for methodological concerns arise from Lord's paradox. Our analysis revealed that RCTs supporting the positive effect of exercise on cognition are likely to include Type I Error(s). This result can be attributed to the use of gain score analysis on pretest-posttest data as well as the presence of control group superiority over the exercise group on baseline cognitive measures. To improve accuracy of causal inferences in this area, analysis of covariance on pretest-posttest data is recommended under the assumption of group equivalence. Important experimental procedures are discussed to maintain group equivalence.

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

Mou, J.I.; King, C.

The focus of this study is to develop a sensor fused process modeling and control methodology to model, assess, and then enhance the performance of a hexapod machine for precision product realization. Deterministic modeling technique was used to derive models for machine performance assessment and enhancement. Sensor fusion methodology was adopted to identify the parameters of the derived models. Empirical models and computational algorithms were also derived and implemented to model, assess, and then enhance the machine performance. The developed sensor fusion algorithms can be implemented on a PC-based open architecture controller to receive information from various sensors, assess themore » status of the process, determine the proper action, and deliver the command to actuators for task execution. This will enhance a hexapod machine`s capability to produce workpieces within the imposed dimensional tolerances.« less

Adaptation of a software development methodology to the implementation of a large-scale data acquisition and control system. [for Deep Space Network

NASA Technical Reports Server (NTRS)

Madrid, G. A.; Westmoreland, P. T.

1983-01-01

A progress report is presented on a program to upgrade the existing NASA Deep Space Network in terms of a redesigned computer-controlled data acquisition system for channelling tracking, telemetry, and command data between a California-based control center and three signal processing centers in Australia, California, and Spain. The methodology for the improvements is oriented towards single subsystem development with consideration for a multi-system and multi-subsystem network of operational software. Details of the existing hardware configurations and data transmission links are provided. The program methodology includes data flow design, interface design and coordination, incremental capability availability, increased inter-subsystem developmental synthesis and testing, system and network level synthesis and testing, and system verification and validation. The software has been implemented thus far to a 65 percent completion level, and the methodology being used to effect the changes, which will permit enhanced tracking and communication with spacecraft, has been concluded to feature effective techniques.

Continuous Trailing-Edge Flaps for Primary Flight Control of a Helicopter Main Rotor

NASA Technical Reports Server (NTRS)

Thornburgh, Robert P.; Kreshock, Andrew R.; Wilbur, Matthew L.; Sekula, Martin K.; Shen, Jinwei

2014-01-01

The use of continuous trailing-edge flaps (CTEFs) for primary flight control of a helicopter main rotor is studied. A practical, optimized bimorph design with Macro-Fiber Composite actuators is developed for CTEF control, and a coupled structures and computational fluid dynamics methodology is used to study the fundamental behavior of an airfoil with CTEFs. These results are used within a comprehensive rotorcraft analysis model to study the control authority requirements of the CTEFs when utilized for primary flight control of a utility class helicopter. A study of the effect of blade root pitch index (RPI) on CTEF control authority is conducted, and the impact of structural and aerodynamic model complexity on the comprehensive analysis results is presented. The results show that primary flight control using CTEFs is promising; however, a more viable option may include the control of blade RPI, as well.

On a program manifold's stability of one contour automatic control systems

NASA Astrophysics Data System (ADS)

Zumatov, S. S.

2017-12-01

Methodology of analysis of stability is expounded to the one contour systems automatic control feedback in the presence of non-linearities. The methodology is based on the use of the simplest mathematical models of the nonlinear controllable systems. Stability of program manifolds of one contour automatic control systems is investigated. The sufficient conditions of program manifold's absolute stability of one contour automatic control systems are obtained. The Hurwitz's angle of absolute stability was determined. The sufficient conditions of program manifold's absolute stability of control systems by the course of plane in the mode of autopilot are obtained by means Lyapunov's second method.

Impact of rehabilitation on self-concept following traumatic brain injury: An exploratory systematic review of intervention methodology and efficacy.

PubMed

Ownsworth, Tamara; Haslam, Catherine

2016-01-01

To date, reviews of rehabilitation efficacy after traumatic brain injury (TBI) have overlooked the impact on sense of self, focusing instead on functional impairment and psychological distress. The present review sought to address this gap by critically appraising the methodology and efficacy of intervention studies that assess changes in self-concept. A systematic search of PsycINFO, Medline, CINAHL and PubMed was conducted from inception to September 2013 to identify studies reporting pre- and post-intervention changes on validated measures of self-esteem or self-concept in adults with TBI. Methodological quality of randomised controlled trials (RCTs) was examined using the Physiotherapy Evidence Database (PEDro) scale. A total of 17 studies (10 RCTs, 4 non-RCT group studies, 3 case studies) was identified, which examined the impact of psychotherapy, family-based support, cognitive rehabilitation or activity-based interventions on self-concept. The findings on the efficacy of these interventions were mixed, with only 10 studies showing some evidence of improvement in self-concept based on within-group or pre-post comparisons. Such findings highlight the need for greater focus on the impact of rehabilitation on self-understanding with improved assessment and intervention methodology. We draw upon theories of identity reconstruction and highlight implications for the design and evaluation of identity-oriented interventions that can supplement existing rehabilitation programmes for people with TBI.

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.

Methodology for Knowledge Synthesis of the Management of Vaccination Pain and Needle Fear.

PubMed

Taddio, Anna; McMurtry, C Meghan; Shah, Vibhuti; Yoon, Eugene W; Uleryk, Elizabeth; Pillai Riddell, Rebecca; Lang, Eddy; Chambers, Christine T; Noel, Melanie; MacDonald, Noni E

2015-10-01

A knowledge synthesis was undertaken to inform the development of a revised and expanded clinical practice guideline about managing vaccination pain in children to include the management of pain across the lifespan and the management of fear in individuals with high levels of needle fear. This manuscript describes the methodological details of the knowledge synthesis and presents the list of included clinical questions, critical and important outcomes, search strategy, and search strategy results. The Grading of Assessments, Recommendations, Development and Evaluation (GRADE) and Cochrane methodologies provided the general framework. The project team voted on clinical questions for inclusion and critically important and important outcomes. A broad search strategy was used to identify relevant randomized-controlled trials and quasi-randomized-controlled trials. Quality of research evidence was assessed using the Cochrane risk of bias tool and quality across studies was assessed using GRADE. Multiple measures of the same construct within studies (eg, observer-rated and parent-rated infant distress) were combined before pooling. The standardized mean difference and 95% confidence intervals (CI) or relative risk and 95% CI was used to express the effects of an intervention. Altogether, 55 clinical questions were selected for inclusion in the knowledge synthesis; 49 pertained to pain management during vaccine injections and 6 pertained to fear management in individuals with high levels of needle fear. Pain, fear, and distress were typically prioritized as critically important outcomes across clinical questions. The search strategy identified 136 relevant studies. This manuscript describes the methodological details of a knowledge synthesis about pain management during vaccination and fear management in individuals with high levels of needle fear. Subsequent manuscripts in this series will present the results for the included questions.

On the design of decoupling controllers for advanced rotorcraft in the hover case

NASA Technical Reports Server (NTRS)

Fan, M. K. H.; Tits, A.; Barlow, J.; Tsing, N. K.; Tischler, M.; Takahashi, M.

1991-01-01

A methodology for design of helicopter control systems is proposed that can account for various types of concurrent specifications: stability, decoupling between longitudinal and lateral motions, handling qualities, and physical limitations of the swashplate motions. This is achieved by synergistic use of analytical techniques (Q-parameterization of all stabilizing controllers, transfer function interpolation) and advanced numerical optimization techniques. The methodology is used to design a controller for the UH-60 helicopter in hover. Good results are achieved for decoupling and handling quality specifications.

An experiment-based comparative study of fuzzy logic control

NASA Technical Reports Server (NTRS)

Berenji, Hamid R.; Chen, Yung-Yaw; Lee, Chuen-Chein; Murugesan, S.; Jang, Jyh-Shing

1989-01-01

An approach is presented to the control of a dynamic physical system through the use of approximate reasoning. The approach has been implemented in a program named POLE, and the authors have successfully built a prototype hardware system to solve the cartpole balancing problem in real-time. The approach provides a complementary alternative to the conventional analytical control methodology and is of substantial use when a precise mathematical model of the process being controlled is not available. A set of criteria for comparing controllers based on approximate reasoning and those based on conventional control schemes is furnished.

Optimization-based controller design for rotorcraft

NASA Technical Reports Server (NTRS)

Tsing, N.-K.; Fan, M. K. H.; Barlow, J.; Tits, A. L.; Tischler, M. B.

1993-01-01

An optimization-based methodology for linear control system design is outlined by considering the design of a controller for a UH-60 rotorcraft in hover. A wide range of design specifications is taken into account: internal stability, decoupling between longitudinal and lateral motions, handling qualities, and rejection of windgusts. These specifications are investigated while taking into account physical limitations in the swashplate displacements and rates of displacement. The methodology crucially relies on user-machine interaction for tradeoff exploration.

Safety of High Speed Ground Transportation Systems : Analytical Methodology for Safety Validation of Computer Controlled Subsystems : Volume 2. Development of a Safety Validation Methodology

DOT National Transportation Integrated Search

1995-01-01

This report describes the development of a methodology designed to assure that a sufficiently high level of safety is achieved and maintained in computer-based systems which perform safety cortical functions in high-speed rail or magnetic levitation ...

Analytical methodology for safety validation of computer controlled subsystems. Volume 1 : state-of-the-art and assessment of safety verification/validation methodologies

DOT National Transportation Integrated Search

1995-09-01

This report describes the development of a methodology designed to assure that a sufficiently high level of safety is achieved and maintained in computer-based systems which perform safety critical functions in high-speed rail or magnetic levitation ...

Mind-body Therapies for Menopausal Symptoms: A Systematic Review

PubMed Central

Innes, Kim E; Selfe, Terry Kit; Vishnu, Abhishek

2010-01-01

Objective To systematically review the peer-reviewed literature regarding the effects of self-administered mind-body therapies on menopausal symptoms. Methods To identify qualifying studies, we searched 10 scientific databases and scanned bibliographies of relevant review papers and all identified articles. The methodological quality of all studies was assessed systematically using predefined criteria. Results Twenty-one papers representing 18 clinical trials from 6 countries met our inclusion criteria, including 12 randomized controlled trials (N=719), 1 non-randomized controlled trial (N=58), and 5 uncontrolled trials (N=105). Interventions included yoga and/or meditation-based programs, tai chi, and other relaxation practices, including muscle relaxation and breath-based techniques, relaxation response training, and low frequency sound-wave therapy. Eight of the nine studies of yoga, tai chi, and meditation-based programs reported improvement in overall menopausal and vasomotor symptoms; six of seven trials indicated improvement in mood and sleep with yoga-based programs, and four studies reported reduced musculoskeletal pain. Results from the remaining nine trials suggest that breath-based and other relaxation therapies also show promise for alleviating vasomotor and other menopausal symptoms, although intergroup findings were mixed. Most studies reviewed suffered methodological or other limitations, complicating interpretation of findings. Conclusions Collectively, findings of these studies suggest that yoga-based and certain other mind-body therapies may be beneficial for alleviating specific menopausal symptoms. However, the limitations characterizing most studies hinder interpretation of findings and preclude firm conclusions regarding efficacy. Additional large, methodologically sound trials are needed to determine the effects of specific mind-body therapies on menopausal symptoms, examine long-term outcomes, and investigate underlying mechanisms. PMID:20167444

Mindfulness and perinatal mental health: A systematic review.

PubMed

Hall, Helen G; Beattie, Jill; Lau, Rosalind; East, Christine; Anne Biro, Mary

2016-02-01

Perinatal stress is associated with adverse maternal and infant outcomes. Mindfulness training may offer a safe and acceptable strategy to support perinatal mental health. To critically appraise and synthesise the best available evidence regarding the effectiveness of mindfulness training during pregnancy to support perinatal mental health. The search for relevant studies was conducted in six electronic databases and in the grey literature. Eligible studies were assessed for methodological quality according to standardised critical appraisal instruments. Data were extracted and recorded on a pre-designed form and then entered into Review Manager. Nine studies were included in the data synthesis. It was not appropriate to combine the study results because of the variation in methodologies and the interventions tested. Statistically significant improvements were found in small studies of women undertaking mindfulness awareness training in one study for stress (mean difference (MD) -5.28, 95% confidence intervals (CI) -10.4 to -0.42, n=22), two for depression (for example MD -5.48, 95% CI -8.96 to -2.0, n=46) and four for anxiety (for example, MD -6.50, 95% CI -10.95 to -2.05, n=32). However the findings of this review are limited by significant methodological issues within the current research studies. There is insufficient evidence from high quality research on which to base recommendations about the effectiveness of mindfulness to promote perinatal mental health. The limited positive findings support the design and conduct of adequately powered, longitudinal randomised controlled trials, with active controls. Copyright © 2015 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.

Disturbance accommodating control design for wind turbines using solvability conditions

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

Wang, Na; Wright, Alan D.; Balas, Mark J.

In this study, solvability conditions for disturbance accommodating control (DAC) have been discussed and applied on wind turbine controller design in above-rated wind speed to regulate rotor speed and to mitigate turbine structural loads. DAC incorporates a predetermined waveform model and uses it as part of the state-space formulation, which is known as the internal model principle to reduce or minimize the wind disturbance effects on the outputs of the wind turbine. An asymptotically stabilizing DAC controller with disturbance impact on the wind turbine being totally canceled out can be found if certain conditions are fulfilled. Designing a rotor speedmore » regulation controller without steady-state error is important for applying linear control methodology such as DAC on wind turbines. Therefore, solvability conditions of DAC without steady-state error are attractive and can be taken as examples when designing a multitask turbine controller. DAC controllers solved via Moore-Penrose Pseudoinverse and the Kronecker product are discussed, and solvability conditions of using them are given. Additionally, a new solvability condition based on inverting the feed-through D term is proposed for the sake of reducing computational burden in the Kronecker product. Applications of designing collective pitch and independent pitch controllers based on DAC are presented. Recommendations of designing a DAC-based wind turbine controller are given. A DAC controller motivated by the proposed solvability condition that utilizes the inverse of feed-through D term is developed to mitigate the blade flapwise once-per-revolution bending moment together with a standard proportional integral controller in the control loop to assist rotor speed regulation. Simulation studies verify the discussed solvability conditions of DAC and show the effectiveness of the proposed DAC control design methodology.« less

Disturbance accommodating control design for wind turbines using solvability conditions

DOE PAGES

Wang, Na; Wright, Alan D.; Balas, Mark J.

2017-02-07

In this study, solvability conditions for disturbance accommodating control (DAC) have been discussed and applied on wind turbine controller design in above-rated wind speed to regulate rotor speed and to mitigate turbine structural loads. DAC incorporates a predetermined waveform model and uses it as part of the state-space formulation, which is known as the internal model principle to reduce or minimize the wind disturbance effects on the outputs of the wind turbine. An asymptotically stabilizing DAC controller with disturbance impact on the wind turbine being totally canceled out can be found if certain conditions are fulfilled. Designing a rotor speedmore » regulation controller without steady-state error is important for applying linear control methodology such as DAC on wind turbines. Therefore, solvability conditions of DAC without steady-state error are attractive and can be taken as examples when designing a multitask turbine controller. DAC controllers solved via Moore-Penrose Pseudoinverse and the Kronecker product are discussed, and solvability conditions of using them are given. Additionally, a new solvability condition based on inverting the feed-through D term is proposed for the sake of reducing computational burden in the Kronecker product. Applications of designing collective pitch and independent pitch controllers based on DAC are presented. Recommendations of designing a DAC-based wind turbine controller are given. A DAC controller motivated by the proposed solvability condition that utilizes the inverse of feed-through D term is developed to mitigate the blade flapwise once-per-revolution bending moment together with a standard proportional integral controller in the control loop to assist rotor speed regulation. Simulation studies verify the discussed solvability conditions of DAC and show the effectiveness of the proposed DAC control design methodology.« less

Autism Spectrum Disorder (ASD) Prevalence in Somali and Non-Somali Children

ERIC Educational Resources Information Center

Hewitt, Amy; Hall-Lande, Jennifer; Hamre, Kristin; Esler, Amy N.; Punyko, Judy; Reichle, Joe; Gulaid, Anab A.

2016-01-01

The current study presents results from an autism spectrum disorder (ASD) public health surveillance project conducted in Minneapolis. The study was designed to compare ASD prevalence in Somali children (ages 7-9) to that of non-Somali children. The study adapted methodology used by the Centers for Disease Control and Prevention's Autism and…

The Literature Review of Analytical Support to Defence Transformation: Lessons Learned from Turkish Air Force Transformation Activities

DTIC Science & Technology

2010-04-01

available [11]. Additionally, Table-3 is a guide for DMAIC methodology including 29 different methods [12]. RTO-MP-SAS-081 6 - 4 NATO UNCLASSIFIED NATO...Table 3: DMAIC Methodology (5-Phase Methodology). Define Measure Analyze Improve Control Project Charter Prioritization Matrix 5 Whys Analysis...Methodology Scope [13] DMAIC PDCA Develop performance priorities This is a preliminary stage that precedes specific improvement projects, and the aim

Factors influencing tests of auditory processing: a perspective on current issues and relevant concerns.

PubMed

Cacace, Anthony T; McFarland, Dennis J

2013-01-01

Tests of auditory perception, such as those used in the assessment of central auditory processing disorders ([C]APDs), represent a domain in audiological assessment where measurement of this theoretical construct is often confounded by nonauditory abilities due to methodological shortcomings. These confounds include the effects of cognitive variables such as memory and attention and suboptimal testing paradigms, including the use of verbal reproduction as a form of response selection. We argue that these factors need to be controlled more carefully and/or modified so that their impact on tests of auditory and visual perception is only minimal. To advocate for a stronger theoretical framework than currently exists and to suggest better methodological strategies to improve assessment of auditory processing disorders (APDs). Emphasis is placed on adaptive forced-choice psychophysical methods and the use of matched tasks in multiple sensory modalities to achieve these goals. Together, this approach has potential to improve the construct validity of the diagnosis, enhance and develop theory, and evolve into a preferred method of testing. Examination of methods commonly used in studies of APDs. Where possible, currently used methodology is compared to contemporary psychophysical methods that emphasize computer-controlled forced-choice paradigms. In many cases, the procedures used in studies of APD introduce confounding factors that could be minimized if computer-controlled forced-choice psychophysical methods were utilized. Ambiguities of interpretation, indeterminate diagnoses, and unwanted confounds can be avoided by minimizing memory and attentional demands on the input end and precluding the use of response-selection strategies that use complex motor processes on the output end. Advocated are the use of computer-controlled forced-choice psychophysical paradigms in combination with matched tasks in multiple sensory modalities to enhance the prospect of obtaining a valid diagnosis. American Academy of Audiology.

A systematic review of physical therapy interventions for patients with anorexia and bulemia nervosa.

PubMed

Vancampfort, Davy; Vanderlinden, Johan; De Hert, Marc; Soundy, Andrew; Adámkova, Milena; Skjaerven, Liv Helvik; Catalán-Matamoros, Daniel; Lundvik Gyllensten, Amanda; Gómez-Conesa, Antonia; Probst, Michel

2014-01-01

The purpose of this systematic review was to summarise the evidence from randomised controlled trials examining the effectiveness of physical therapy compared with care as usual or a wait-list condition on eating pathology and on physiological and psychological parameters in patients with anorexia and bulimia nervosa. EMBASE, PsycINFO, PubMed, Cumulative Index to Nursing and Allied Health Literature, Physiotherapy Evidence Database and The Cochrane Library were searched from their inception until February, 2013. Articles were eligible if they utilised a randomised controlled trial design, compared physical therapy with a placebo condition, control intervention, or standard care and included patients with anorexia and bulimia nervosa. The methodological quality was assessed with the Jadad scale. Eight randomised controlled trials involving 213 patients (age range: 16-36 years) met all selection criteria. Three of the 8 included studies were of strong methodological quality (Jadad score≥3). Major methodological weaknesses were attrition and selection bias. The main results demonstrate that aerobic and resistance training result in significantly increased muscle strength, body mass index and body fat percentage in anorexia patients. In addition, aerobic exercise, yoga, massage and basic body awareness therapy significantly lowered scores of eating pathology and depressive symptoms in both anorexia and bulimia nervosa patients. No adverse effects were reported. The paucity and heterogeneity of available studies limits overall conclusions and highlights the need for further research. Implications for Rehabilitation Supervised physical therapy might increase weight in anorexia nervosa patients. Aerobic exercise, massage, basic body awareness therapy and yoga might reduce eating pathology in patients with anorexia and bulimia nervosa. Aerobic exercise, yoga and basic body awareness therapy might improve mental and physical quality of life in patients with an eating disorder.

Alternatives for jet engine control

NASA Technical Reports Server (NTRS)

Sain, M. K.

1980-01-01

Nonlinear modeling researches involving the use of tensor analysis are presented. Progress was achieved by extending the studies to a controlled equation and by considering more complex situations. Included in the report are calculations illustrating the modeling methodology for cases in which variables take values in real spaces of dimension up to three, and in which the degree of tensor term retention is as high as three.

Training Preschoolers on First-Order False Belief Understanding: Transfer on Advanced ToM Skills and Metamemory

ERIC Educational Resources Information Center

Lecce, Serena; Bianco, Federica; Demicheli, Patrizia; Cavallini, Elena

2014-01-01

This study investigated the relation between theory of mind (ToM) and metamemory knowledge using a training methodology. Sixty-two 4- to 5-year-old children were recruited and randomly assigned to one of two training conditions: A first-order false belief (ToM) and a control condition. Intervention and control groups were equivalent at pretest for…

Robust decentralized controller for minimizing coupling effect in single inductor multiple output DC-DC converter operating in continuous conduction mode.

PubMed

Medeiros, Renan Landau Paiva de; Barra, Walter; Bessa, Iury Valente de; Chaves Filho, João Edgar; Ayres, Florindo Antonio de Cavalho; Neves, Cleonor Crescêncio das

2018-02-01

This paper describes a novel robust decentralized control design methodology for a single inductor multiple output (SIMO) DC-DC converter. Based on a nominal multiple input multiple output (MIMO) plant model and performance requirements, a pairing input-output analysis is performed to select the suitable input to control each output aiming to attenuate the loop coupling. Thus, the plant uncertainty limits are selected and expressed in interval form with parameter values of the plant model. A single inductor dual output (SIDO) DC-DC buck converter board is developed for experimental tests. The experimental results show that the proposed methodology can maintain a desirable performance even in the presence of parametric uncertainties. Furthermore, the performance indexes calculated from experimental data show that the proposed methodology outperforms classical MIMO control techniques. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

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.

Risk of bias and methodological issues in randomised controlled trials of acupuncture for knee osteoarthritis: a cross-sectional study.

PubMed

Jia, Pengli; Tang, Li; Yu, Jiajie; Lee, Andy H; Zhou, Xu; Kang, Deying; Luo, Yanan; Liu, Jiali; Sun, Xin

2018-03-06

To assess risk of bias and to investigate methodological issues concerning the design, conduct and analysis of randomised controlled trials (RCTs) testing acupuncture for knee osteoarthritis (KOA). PubMed, EMBASE, Cochrane Central Register of Controlled Trials and four major Chinese databases were searched for RCTs that investigated the effect of acupuncture for KOA. The Cochrane tool was used to examine the risk of bias of eligible RCTs. Their methodological details were examined using a standardised and pilot-tested questionnaire of 48 items, together with the association between four predefined factors and important methodological quality indicators. A total of 248 RCTs were eligible, of which 39 (15.7%) used computer-generated randomisation sequence. Of the 31 (12.5%) trials that stated the allocation concealment, only one used central randomisation. Twenty-five (10.1%) trials mentioned that their acupuncture procedures were standardised, but only 18 (7.3%) specified how the standardisation was achieved. The great majority of trials (n=233, 94%) stated that blinding was in place, but 204 (87.6%) did not clarify who was blinded. Only 27 (10.9%) trials specified the primary outcome, for which 7 used intention-to-treat analysis. Only 17 (6.9%) trials included details on sample size calculation; none preplanned an interim analysis and associated stopping rule. In total, 46 (18.5%) trials explicitly stated that loss to follow-up occurred, but only 6 (2.4%) provided some information to deal with the issue. No trials prespecified, conducted or reported any subgroup or adjusted analysis for the primary outcome. The overall risk of bias was high among published RCTs testing acupuncture for KOA. Methodological limitations were present in many important aspects of design, conduct and analyses. These findings inform the development of evidence-based methodological guidance for future trials assessing the effect of acupuncture for KOA. © 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.

Quality Assessment of Studies Published in Open Access and Subscription Journals: Results of a Systematic Evaluation.

PubMed

Pastorino, Roberta; Milovanovic, Sonja; Stojanovic, Jovana; Efremov, Ljupcho; Amore, Rosarita; Boccia, Stefania

2016-01-01

Along with the proliferation of Open Access (OA) publishing, the interest for comparing the scientific quality of studies published in OA journals versus subscription journals has also increased. With our study we aimed to compare the methodological quality and the quality of reporting of primary epidemiological studies and systematic reviews and meta-analyses published in OA and non-OA journals. In order to identify the studies to appraise, we listed all OA and non-OA journals which published in 2013 at least one primary epidemiologic study (case-control or cohort study design), and at least one systematic review or meta-analysis in the field of oncology. For the appraisal, we picked up the first studies published in 2013 with case-control or cohort study design from OA journals (Group A; n = 12), and in the same time period from non-OA journals (Group B; n = 26); the first systematic reviews and meta-analyses published in 2013 from OA journals (Group C; n = 15), and in the same time period from non-OA journals (Group D; n = 32). We evaluated the methodological quality of studies by assessing the compliance of case-control and cohort studies to Newcastle and Ottawa Scale (NOS) scale, and the compliance of systematic reviews and meta-analyses to Assessment of Multiple Systematic Reviews (AMSTAR) scale. The quality of reporting was assessed considering the adherence of case-control and cohort studies to STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) checklist, and the adherence of systematic reviews and meta-analyses to Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) checklist. Among case-control and cohort studies published in OA and non-OA journals, we did not observe significant differences in the median value of NOS score (Group A: 7 (IQR 7-8) versus Group B: 8 (7-9); p = 0.5) and in the adherence to STROBE checklist (Group A, 75% versus Group B, 80%; p = 0.1). The results did not change after adjustment for impact factor. The compliance with AMSTAR and adherence to PRISMA checklist were comparable between systematic reviews and meta-analyses published in OA and non-OA journals (Group C, 46.0% versus Group D, 55.0%; p = 0.06), (Group C, 72.0% versus Group D, 76.0%; p = 0.1), respectively). The epidemiological studies published in OA journals in the field of oncology approach the same methodological quality and quality of reporting as studies published in non-OA journals.

Quality Assessment of Studies Published in Open Access and Subscription Journals: Results of a Systematic Evaluation

PubMed Central

Pastorino, Roberta; Milovanovic, Sonja; Stojanovic, Jovana; Efremov, Ljupcho; Amore, Rosarita; Boccia, Stefania

2016-01-01

Introduction Along with the proliferation of Open Access (OA) publishing, the interest for comparing the scientific quality of studies published in OA journals versus subscription journals has also increased. With our study we aimed to compare the methodological quality and the quality of reporting of primary epidemiological studies and systematic reviews and meta-analyses published in OA and non-OA journals. Methods In order to identify the studies to appraise, we listed all OA and non-OA journals which published in 2013 at least one primary epidemiologic study (case-control or cohort study design), and at least one systematic review or meta-analysis in the field of oncology. For the appraisal, we picked up the first studies published in 2013 with case-control or cohort study design from OA journals (Group A; n = 12), and in the same time period from non-OA journals (Group B; n = 26); the first systematic reviews and meta-analyses published in 2013 from OA journals (Group C; n = 15), and in the same time period from non-OA journals (Group D; n = 32). We evaluated the methodological quality of studies by assessing the compliance of case-control and cohort studies to Newcastle and Ottawa Scale (NOS) scale, and the compliance of systematic reviews and meta-analyses to Assessment of Multiple Systematic Reviews (AMSTAR) scale. The quality of reporting was assessed considering the adherence of case-control and cohort studies to STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) checklist, and the adherence of systematic reviews and meta-analyses to Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) checklist. Results Among case-control and cohort studies published in OA and non-OA journals, we did not observe significant differences in the median value of NOS score (Group A: 7 (IQR 7–8) versus Group B: 8 (7–9); p = 0.5) and in the adherence to STROBE checklist (Group A, 75% versus Group B, 80%; p = 0.1). The results did not change after adjustment for impact factor. The compliance with AMSTAR and adherence to PRISMA checklist were comparable between systematic reviews and meta-analyses published in OA and non-OA journals (Group C, 46.0% versus Group D, 55.0%; p = 0.06), (Group C, 72.0% versus Group D, 76.0%; p = 0.1), respectively). Conclusion The epidemiological studies published in OA journals in the field of oncology approach the same methodological quality and quality of reporting as studies published in non-OA journals. PMID:27167982

Is aggression in children with behavioural and emotional difficulties associated with television viewing and video game playing? A systematic review.

PubMed

Mitrofan, O; Paul, M; Spencer, N

2009-01-01

Possible associations between television viewing and video game playing and children's aggression have become public health concerns. We did a systematic review of studies that examined such associations, focussing on children and young people with behavioural and emotional difficulties, who are thought to be more susceptible. We did computer-assisted searches of health and social science databases, gateways, publications from relevant organizations and for grey literature; scanned bibliographies; hand-searched key journals; and corresponded with authors. We critically appraised all studies. A total of 12 studies: three experiments with children with behavioural and emotional difficulties found increased aggression after watching aggressive as opposed to low-aggressive content television programmes, one found the opposite and two no clear effect, one found such children no more likely than controls to imitate aggressive television characters. One case-control study and one survey found that children and young people with behavioural and emotional difficulties watched more television than controls; another did not. Two studies found that children and young people with behavioural and emotional difficulties viewed more hours of aggressive television programmes than controls. One study on video game use found that young people with behavioural and emotional difficulties viewed more minutes of violence and played longer than controls. In a qualitative study children with behavioural and emotional difficulties, but not their parents, did not associate watching television with aggression. All studies had significant methodological flaws. None was based on power calculations. This systematic review found insufficient, contradictory and methodologically flawed evidence on the association between television viewing and video game playing and aggression in children and young people with behavioural and emotional difficulties. If public health advice is to be evidence-based, good quality research is needed.

Methodological characteristics and treatment effect sizes in oral health randomised controlled trials: Is there a relationship? Protocol for a meta-epidemiological study.

PubMed

Saltaji, Humam; Armijo-Olivo, Susan; Cummings, Greta G; Amin, Maryam; Flores-Mir, Carlos

2014-02-25

It is fundamental that randomised controlled trials (RCTs) are properly conducted in order to reach well-supported conclusions. However, there is emerging evidence that RCTs are subject to biases which can overestimate or underestimate the true treatment effect, due to flaws in the study design characteristics of such trials. The extent to which this holds true in oral health RCTs, which have some unique design characteristics compared to RCTs in other health fields, is unclear. As such, we aim to examine the empirical evidence quantifying the extent of bias associated with methodological and non-methodological characteristics in oral health RCTs. We plan to perform a meta-epidemiological study, where a sample size of 60 meta-analyses (MAs) including approximately 600 RCTs will be selected. The MAs will be randomly obtained from the Oral Health Database of Systematic Reviews using a random number table; and will be considered for inclusion if they include a minimum of five RCTs, and examine a therapeutic intervention related to one of the recognised dental specialties. RCTs identified in selected MAs will be subsequently included if their study design includes a comparison between an intervention group and a placebo group or another intervention group. Data will be extracted from selected trials included in MAs based on a number of methodological and non-methodological characteristics. Moreover, the risk of bias will be assessed using the Cochrane Risk of Bias tool. Effect size estimates and measures of variability for the main outcome will be extracted from each RCT included in selected MAs, and a two-level analysis will be conducted using a meta-meta-analytic approach with a random effects model to allow for intra-MA and inter-MA heterogeneity. The intended audiences of the findings will include dental clinicians, oral health researchers, policymakers and graduate students. The aforementioned will be introduced to the findings through workshops, seminars, round table discussions and targeted individual meetings. Other opportunities for knowledge transfer will be pursued such as key dental conferences. Finally, the results will be published as a scientific report in a dental peer-reviewed journal.

Optimal early active mobilisation protocol after extensor tendon repairs in zones V and VI: A systematic review of literature.

PubMed

Collocott, Shirley Jf; Kelly, Edel; Ellis, Richard F

2018-03-01

Early mobilisation protocols after repair of extensor tendons in zone V and VI provide better outcomes than immobilisation protocols. This systematic review investigated different early active mobilisation protocols used after extensor tendon repair in zone V and VI. The purpose was to determine whether any one early active mobilisation protocol provides superior results. An extensive literature search was conducted to identify articles investigating the outcomes of early active mobilisation protocols after extensor tendon repair in zone V and VI. Databases searched were AMED, Embase, Medline, Cochrane and CINAHL. Studies were included if they involved participants with extensor tendon repairs in zone V and VI in digits 2-5 and described a post-operative rehabilitation protocol which allowed early active metacarpophalangeal joint extension. Study designs included were randomised controlled trials, observational studies, cohort studies and case series. The Structured Effectiveness Quality Evaluation Scale was used to evaluate the methodological quality of the included studies. Twelve articles met the inclusion criteria. Two types of early active mobilisation protocols were identified: controlled active motion protocols and relative motion extension splinting protocols. Articles describing relative motion extension splinting protocols were more recent but of lower methodological quality than those describing controlled active motion protocols. Participants treated with controlled active motion and relative motion extension splinting protocols had similar range of motion outcomes, but those in relative motion extension splinting groups returned to work earlier. The evidence reviewed suggested that relative motion extension splinting protocols may allow an earlier return to function than controlled active motion protocols without a greater risk of complication.

Harvesting model uncertainty for the simulation of interannual variability

NASA Astrophysics Data System (ADS)

Misra, Vasubandhu

2009-08-01

An innovative modeling strategy is introduced to account for uncertainty in the convective parameterization (CP) scheme of a coupled ocean-atmosphere model. The methodology involves calling the CP scheme several times at every given time step of the model integration to pick the most probable convective state. Each call of the CP scheme is unique in that one of its critical parameter values (which is unobserved but required by the scheme) is chosen randomly over a given range. This methodology is tested with the relaxed Arakawa-Schubert CP scheme in the Center for Ocean-Land-Atmosphere Studies (COLA) coupled general circulation model (CGCM). Relative to the control COLA CGCM, this methodology shows improvement in the El Niño-Southern Oscillation simulation and the Indian summer monsoon precipitation variability.

Methodological proceedings to evaluate the physical accessibility in urban historic sites.

PubMed

Ribeiro, Gabriela Sousa; Martins, Laura Bezerra; Monteiro, Circe Maria Gama

2012-01-01

Historic urban sites are set by cultural and social diversities, generating multiple activities and use and access to these sites should be available to all people including those with disabilities. Taking into consideration that using the same methodology that was used in different historic sites researches with positive results facilitates replication, we aimed to develop methodological procedures that identify conditions of physical accessibility in open public spaces and access to public buildings in historic urban sites to support proposals about design requirements for improvements to the problems diagnosed and control inadequacies of the physical environment. The study methods and techniques from different areas of knowledge culminated in a proposal built with an emphasis on user participation that could be applied with low cost and in relatively short period of time.

Innovative Methodology For Detection of Fracture-Controlled Sweet Spots in the Northern Appalachian Basin

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

Jacobi, Rober

2007-03-28

This Topical Report (#6 of 9) consists of the figures 3.6-13 to (and including) 3.6-18 (and appropriate figure captions) that accompany the Final Technical Progress Report entitled: “Innovative Methodology for Detection of Fracture-Controlled Sweet Spots in the Northern Appalachian Basin” for DOE/NETL Award DE-AC26-00NT40698.

Chase: Control of Heterogeneous Autonomous Sensors for Situational Awareness

DTIC Science & Technology

2016-08-03

remained the discovery and analysis of new foundational methodology for information collection and fusion that exercises rigorous feedback control over...simultaneously achieve quantified information and physical objectives. New foundational methodology for information collection and fusion that exercises...11.2.1. In the general area of novel stochastic systems analysis it seems appropriate to mention the pioneering work on non -Bayesian distributed learning

TISSUE DISTRIBUTION AND HISTOLOGY OF FITC AND FITC-17B-ESTRADIOL IN CUNNER (TAUTOGOLABRUS ADSPERSUS) AFTER SUBCUTANEOUS IMPLANTATION IN A CONTROL RELEASE MATRIX

EPA Science Inventory

Peritoneal injection is a major route for chemical introduction into fish for toxicological studies. This procedure, however, causes rapid exposure to toxicants. Long-term studies to determine effects of estrogenic chemicals on fish reproduction require a methodology that allows ...

Improving Learning Performance in Laboratory Instruction by Means of SMS Messaging

ERIC Educational Resources Information Center

Martinez-Torres, M. R.; Toral, S. L.; Barrero, F.; Gallardo, S.

2007-01-01

The study described in this paper outlines an attempt to explore those factors that contribute to learning performance improvement in laboratory instruction. As a case study, the educational methodology involved in a basic microcontroller course was analyzed. Traditional lab sessions based on the control of peripherals with low interactivity have…

Employing Case Study Methodology in Special Educational Settings

ERIC Educational Resources Information Center

Rouse, Angelise M.

2016-01-01

In general, case studies are a preferred strategy when "how" or "why" questions are being posed, when the investigator has little control over events, and when the focus is on a contemporary phenomenon within some real-life context (Yin, 2009). This article will examine the advantages and disadvantages of employing case study…

Exploring the Effectiveness of a Virtual Learning Methodology in Occupational Therapy Education

ERIC Educational Resources Information Center

Bebeau, Deborah

2016-01-01

This quantitative, randomly controlled study sought to find relationships between occupational therapy students' participation in a virtual situated-case scenario (VSCS) and enhanced perceived self-efficacy as well as academic performance when compared to participation in a text-based case study. To determine effects of participation in a virtual…

Demonstration for Social Change: An Experiment in Local Control.

ERIC Educational Resources Information Center

Gittell, Marilyn; And Others

This evaluative history of New York City's recent experiments in public education documents three projects: Ocean Hill-Brownsville, IS 201, and Two Bridges. This study employs a process oriented and a qualitative methodology which relies most on field observation and participant-observers. The Institute study observed the new community boards,…

Porous starch-based drug delivery systems processed by a microwave route.

PubMed

Malafaya, P B; Elvira, C; Gallardo, A; San Román, J; Reis, R L

2001-01-01

Abstract-A new simple processing route to produce starch-based porous materials was developed based on a microwave baking methodology. This innovative processing route was used to obtain non-loaded controls and loaded drug delivery carriers, incorporating a non-steroid anti-inflammatory agent. This bioactive agent was selected as model drug with expectations that the developed methodology might be used for other drugs and growth factors. The prepared systems were characterized by 1H and 13C NMR spectroscopy which allow the study of the interactions between the starch-based materials and the processing components, i.e, the blowing agents. The porosity of the prepared materials was estimated by measuring their apparent density and studied by comparing drug-loaded and non-loaded carriers. The behaviour of the porous structures, while immersed in aqueous media, was studied in terms of swelling and degradation, being intimately related to their porosity. Finally, in vitro drug release studies were performed showing a clear burst effect, followed by a slow controlled release of the drug over several days (up to 10 days).

Enhancement of carer skills and patient function in the non-pharmacological management of frontotemporal dementia (FTD): A call for randomised controlled studies

PubMed Central

O'Connor, Claire M.; Clemson, Lindy; da Silva, Thaís Bento Lima; Piguet, Olivier; Hodges, John R.; Mioshi, Eneida

2013-01-01

FTD is a unique condition which manifests with a range of behavioural symptoms, marked dysfunction in activities of daily living (ADL) and increased levels of carer burden as compared to carers of other dementias. No efficacious pharmacological interventions to treat FTD currently exist, and research on pharmacological symptom management is variable. The few studies on non-pharmacological interventions in FTD focus on either the carer or the patients' symptoms, and lack methodological rigour. This paper reviews and discusses current studies utilising non-pharmacological approaches, exposing the clear need for more rigorous methodologies to be applied in this field. Finally, a successful randomised controlled trial helped reduce behaviours of concern in dementia, and through implementing participation in tailored activities, the FTD-specific Tailored Activities Program (TAP) is presented. Crucially, this protocol has scope to target both the person with FTD and their carer. This paper highlights that studies in this area would help to elucidate the potential for using activities to reduce characteristic behaviours in FTD, improving quality of life and the caregiving experience in FTD. PMID:29213832

A systematic review of mosquito coils and passive emanators: defining recommendations for spatial repellency testing methodologies.

PubMed

Ogoma, Sheila B; Moore, Sarah J; Maia, Marta F

2012-12-07

Mosquito coils, vaporizer mats and emanators confer protection against mosquito bites through the spatial action of emanated vapor or airborne pyrethroid particles. These products dominate the pest control market; therefore, it is vital to characterize mosquito responses elicited by the chemical actives and their potential for disease prevention. The aim of this review was to determine effects of mosquito coils and emanators on mosquito responses that reduce human-vector contact and to propose scientific consensus on terminologies and methodologies used for evaluation of product formats that could contain spatial chemical actives, including indoor residual spraying (IRS), long lasting insecticide treated nets (LLINs) and insecticide treated materials (ITMs). PubMed, (National Centre for Biotechnology Information (NCBI), U.S. National Library of Medicine, NIH), MEDLINE, LILAC, Cochrane library, IBECS and Armed Forces Pest Management Board Literature Retrieval System search engines were used to identify studies of pyrethroid based coils and emanators with key-words "Mosquito coils" "Mosquito emanators" and "Spatial repellents". It was concluded that there is need to improve statistical reporting of studies, and reach consensus in the methodologies and terminologies used through standardized testing guidelines. Despite differing evaluation methodologies, data showed that coils and emanators induce mortality, deterrence, repellency as well as reduce the ability of mosquitoes to feed on humans. Available data on efficacy outdoors, dose-response relationships and effective distance of coils and emanators is inadequate for developing a target product profile (TPP), which will be required for such chemicals before optimized implementation can occur for maximum benefits in disease control.

Comparison of standing postural control and gait parameters in people with and without chronic low back pain: a cross-sectional case-control study.

PubMed

MacRae, Catharine Siân; Critchley, Duncan; Lewis, Jeremy S; Shortland, Adam

2018-01-01

Differences in postural control and gait have been identified between people with and without chronic low back pain (CLBP); however, many previous studies present data from small samples, or have used methodologies with questionable reliability. This study, employing robust methodology, hypothesised that there would be a difference in postural control, and spatiotemporal parameters of gait in people with CLBP compared with asymptomatic individuals. This cross-sectional case-control study age-matched and gender-matched 16 CLBP and 16 asymptomatic participants. Participants were assessed barefoot (1) standing, over three 40 s trials, under four posture challenging conditions (2) during gait. Primary outcome was postural stability (assessed by root mean squared error of centre of pressure (CoP) displacement (CoP RMSEAP ) and mean CoP velocity (CoP VELAP ), both in the anteroposterior direction); gait outcomes were hip range of movement and peak moments, walking speed, cadence and stride length, assessed using force plates and a motion analysis system. There were no differences between groups in CoP RMSEAP (P=0.26), or CoP VELAP (P=0.60) for any standing condition. During gait, no differences were observed between groups for spatiotemporal parameters, maximum, minimum and total ranges of hip movement, or peak hip flexor or extensor moments in the sagittal plane. In contrast to previous research, this study suggests that people with mild to moderate CLBP present with similar standing postural control, and parameters of gait to asymptomatic individuals. Treatments directed at influencing postural stability (eg, standing on a wobble board) or specific parameters of gait may be an unnecessary addition to a treatment programme.

Effect of subliminal stimuli on consumer behavior: negative evidence.

PubMed

George, S G; Jennings, L B

1975-12-01

The study corrected methodological weaknesses found in previous experiments designed to test the contentions of motivational research theorists that subliminal stimulation can affect buying behavior. The words "Hershey's Chocolate" were presented to a group of 18 experimental Ss below a forced-choice detection threshold. The 19 control Ss had a blank slide superimposed over the same background media. In a highly controlled buying situation neither experimental nor control Ss purchased Hershey's products, but on comparable chocolate products, the experimental Ss bought 5 and the control Ss, 3. A second study tested 15 experimental and 12 control Ss with the stimulus presented just below a recognition threshold. No experimental Ss bought Hershey's; two control Ss did. No support was found for the claims of motivational research theorists.

A validated methodology for genetic identification of tuna species (genus Thunnus).

PubMed

Viñas, Jordi; Tudela, Sergi

2009-10-27

Tuna species of the genus Thunnus, such as the bluefin tunas, are some of the most important and yet most endangered trade fish in the world. Identification of these species in traded forms, however, may be difficult depending on the presentation of the products, which may hamper conservation efforts on trade control. In this paper, we validated a genetic methodology that can fully distinguish between the eight Thunnus species from any kind of processed tissue. After testing several genetic markers, a complete discrimination of the eight tuna species was achieved using Forensically Informative Nucleotide Sequencing based primarily on the sequence variability of the hypervariable genetic marker mitochondrial DNA control region (mtDNA CR), followed, in some specific cases, by a second validation by a nuclear marker rDNA first internal transcribed spacer (ITS1). This methodology was able to distinguish all tuna species, including those belonging to the subgenus Neothunnus that are very closely related, and in consequence can not be differentiated with other genetic markers of lower variability. This methodology also took into consideration the presence of introgression that has been reported in past studies between T. thynnus, T. orientalis and T. alalunga. Finally, we applied the methodology to cross-check the species identity of 26 processed tuna samples. Using the combination of two genetic markers, one mitochondrial and another nuclear, allows a full discrimination between all eight tuna species. Unexpectedly, the genetic marker traditionally used for DNA barcoding, cytochrome oxidase 1, could not differentiate all species, thus its use as a genetic marker for tuna species identification is questioned.

Virtual reality exposure therapy for the treatment of posttraumatic stress disorder: a methodological review using CONSORT guidelines.

PubMed

Motraghi, Terri E; Seim, Richard W; Meyer, Eric C; Morissette, Sandra B

2014-03-01

Virtual reality exposure therapy (VRET) is an extension of traditional exposure therapy and has been used to treat a variety of anxiety disorders. VRET utilizes a computer-generated virtual environment to present fear-relevant stimuli. Recent studies have evaluated the use of VRET for treatment of PTSD; however, a systematic evaluation of the methodological quality of these studies has yet to be conducted. This review aims to (a) identify treatment outcome studies examining the use of VRET for the treatment of PTSD and (b) appraise the methodological quality of each study using the 2010 Consolidating Standards of Reporting Trials (CONSORT) Statement and its 2008 extension for nonpharmacologic interventions. Two independent assessors conducted a database search (PsycINFO, Medline, CINAHL, Google Scholar) of studies published between January 1990 and June 2013 that reported outcome data comparing VRET with another type of treatment or a control condition. Next, a CONSORT quality appraisal of each study was completed. The search yielded nine unique studies. The CONSORT appraisal revealed that the methodological quality of studies examining VRET as a treatment for PTSD was variable. Although preliminary findings suggest some positive results for VRET as a form of exposure treatment for PTSD, additional research using well-specified randomization procedures, assessor blinding, and monitoring of treatment adherence is warranted. Movement toward greater standardization of treatment manuals, virtual environments, and equipment would further facilitate interpretation and consolidation of this literature. © 2013 Wiley Periodicals, Inc.

A Systematic Review of Autologous Platelet-Rich Plasma and Fat Graft Preparation Methods.

PubMed

Luck, Joshua; Smith, Oliver J; Mosahebi, Afshin

2017-12-01

The addition of platelet-rich plasma (PRP) to adipose tissue may improve fat graft survival, although graft retention rates vary markedly between studies. To what extent this outcome heterogeneity reflects differing methodological factors remains unknown. This systematic review aims to synthesize and critically review methodological approaches to autologous PRP and fat cotransplantation in both human and animal studies. In accordance with PRISMA guidelines, Ovid MEDLINE, Scopus, and Cochrane Library databases were searched from inception to April 2017. Data were extracted from all in vivo studies involving autologous PRP and fat cotransplantation. A secondary aim was to assess reporting of technical detail; authors were not contacted to provide missing data. From 335 articles, 23 studies were included in the qualitative synthesis. Some 21 were performed in humans and 2 in rabbits. Six studies were randomized control trials; the remainder reported on observational data. Methods of PRP extraction and activation varied markedly between studies. Fat graft preparation was comparatively more consistent. Methods of PRP and fat mixing differed significantly, especially with regards to relative volume/volume ratios. Our study represents the first systematic review of methodological factors in autologous PRP and fat cotransplantation. It demonstrates that technical factors in graft preparation and administration vary significantly between in vivo studies. Such methodological heterogeneity may explain observed differences in experimental and clinical outcomes. Reporting of key procedural information is inconsistent and often inadequate. These issues make meaningful evaluation of the PRP-enhanced fat grafting literature difficult and may limit its translation into clinical practice.

Comments on: blood product transfusion in emergency department patients: a case control study of practice patterns and impact on outcome.

PubMed

Karami, Manoochehr; Khazaei, Salman

2017-12-06

Clinical decision makings according studies result require the valid and correct data collection, andanalysis. However, there are some common methodological and statistical issues which may ignore by authors. In individual matched case- control design bias arising from the unconditional analysis instead of conditional analysis. Using an unconditional logistic for matched data causes the imposition of a large number of nuisance parameters which may result in seriously biased estimates.

How completely are physiotherapy interventions described in reports of randomised trials?

PubMed

Yamato, Tiê P; Maher, Chris G; Saragiotto, Bruno T; Hoffmann, Tammy C; Moseley, Anne M

2016-06-01

Incomplete descriptions of interventions are a common problem in reports of randomised controlled trials. To date no study has evaluated the completeness of the descriptions of physiotherapy interventions. To evaluate the completeness of the descriptions of physiotherapy interventions in a random sample of reports of randomised controlled trials (RCTs). A random sample of 200 reports of RCTs from the PEDro database. We included full text papers, written in English, and reporting trials with two arms. We included trials evaluating any type of physiotherapy interventions and subdisciplines. The methodological quality was evaluated using the PEDro scale and completeness of intervention description using the Template for Intervention Description and Replication (TIDieR) checklist. The proportion and 95% confidence interval were calculated for intervention and control groups, and used to present the relationship between completeness and methodological quality, and subdisciplines. Completeness of intervention reporting in physiotherapy RCTs was poor. For intervention groups, 46 (23%) trials did not describe at least half of the items. Reporting was worse for control groups, 149 (75%) trials described less than half of the items. There was no clear difference in the completeness across subdisciplines or methodological quality. Our sample were restricted to trials published in English in 2013. Descriptions of interventions in physiotherapy RCTs are typically incomplete. Authors and journals should aim for more complete descriptions of interventions in physiotherapy trials. Copyright © 2016 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

Benchmarking Controlled Trial--a novel concept covering all observational effectiveness studies.

PubMed

Malmivaara, Antti

2015-06-01

The Benchmarking Controlled Trial (BCT) is a novel concept which covers all observational studies aiming to assess effectiveness. BCTs provide evidence of the comparative effectiveness between health service providers, and of effectiveness due to particular features of the health and social care systems. BCTs complement randomized controlled trials (RCTs) as the sources of evidence on effectiveness. This paper presents a definition of the BCT; compares the position of BCTs in assessing effectiveness with that of RCTs; presents a checklist for assessing methodological validity of a BCT; and pilot-tests the checklist with BCTs published recently in the leading medical journals.

The Efficacy of Eye Movement Desensitization and Reprocessing in Children and Adults Who Have Experienced Complex Childhood Trauma: A Systematic Review of Randomized Controlled Trials.

PubMed

Chen, Runsen; Gillespie, Amy; Zhao, Yanhui; Xi, Yingjun; Ren, Yanping; McLean, Loyola

2018-01-01

Background: Survivors of complex childhood trauma (CT) such as sexual abuse show poorer outcomes compared to single event trauma survivors. A growing number of studies investigate Eye Movement Desensitization and Reprocessing (EMDR) treatment for posttraumatic stress disorder (PTSD), but no systematic reviews have focused on EMDR treatment for CT as an intervention for both adults and children. This study therefore systematically reviewed all randomized controlled trials (RCTs) evaluating the effect of EMDR on PTSD symptoms in adults and children exposed to CT. Methods: Databases including PubMed, Web of Science, and PsycINFO were searched in October 2017. Randomized controlled trials which recruited adult and children with experience of CT, which compared EMDR to alternative treatments or control conditions, and which measured PTSD symptoms were included. Study methodology quality was evaluated with Platinum Standard scale. Results: Six eligible RCTs of 251 participants were included in this systematic review. The results indicated that EMDR was associated with reductions in PTSD symptoms, depression and/or anxiety both post-treatment and at follow-up compared with all other alternative therapies (cognitive behavior therapy, individual/group therapy and fluoxetine) and control treatment (pill placebo, active listening, EMDR delayed treatment, and treatment as usual). However, studies suffered from significant heterogeneity in study populations, length of EMDR treatment, length of follow-up, comparison groups, and outcome measures. One study had a high risk of bias. Discussion: This systematic review suggests that there is growing evidence to support the clinical efficacy of EMDR in treating CT in both children and adults. However, conclusions are limited by the small number of heterogenous trials. Further RCTs with standardized methodologies, as well as studies addressing real world challenges in treating CT are required.

The Efficacy of Eye Movement Desensitization and Reprocessing in Children and Adults Who Have Experienced Complex Childhood Trauma: A Systematic Review of Randomized Controlled Trials

PubMed Central

Chen, Runsen; Gillespie, Amy; Zhao, Yanhui; Xi, Yingjun; Ren, Yanping; McLean, Loyola

2018-01-01

Background: Survivors of complex childhood trauma (CT) such as sexual abuse show poorer outcomes compared to single event trauma survivors. A growing number of studies investigate Eye Movement Desensitization and Reprocessing (EMDR) treatment for posttraumatic stress disorder (PTSD), but no systematic reviews have focused on EMDR treatment for CT as an intervention for both adults and children. This study therefore systematically reviewed all randomized controlled trials (RCTs) evaluating the effect of EMDR on PTSD symptoms in adults and children exposed to CT. Methods: Databases including PubMed, Web of Science, and PsycINFO were searched in October 2017. Randomized controlled trials which recruited adult and children with experience of CT, which compared EMDR to alternative treatments or control conditions, and which measured PTSD symptoms were included. Study methodology quality was evaluated with Platinum Standard scale. Results: Six eligible RCTs of 251 participants were included in this systematic review. The results indicated that EMDR was associated with reductions in PTSD symptoms, depression and/or anxiety both post-treatment and at follow-up compared with all other alternative therapies (cognitive behavior therapy, individual/group therapy and fluoxetine) and control treatment (pill placebo, active listening, EMDR delayed treatment, and treatment as usual). However, studies suffered from significant heterogeneity in study populations, length of EMDR treatment, length of follow-up, comparison groups, and outcome measures. One study had a high risk of bias. Discussion: This systematic review suggests that there is growing evidence to support the clinical efficacy of EMDR in treating CT in both children and adults. However, conclusions are limited by the small number of heterogenous trials. Further RCTs with standardized methodologies, as well as studies addressing real world challenges in treating CT are required. PMID:29695993

Application of an integrated flight/propulsion control design methodology to a STOVL aircraft

NASA Technical Reports Server (NTRS)

Garg, Sanjay; Mattern, Duane L.

1991-01-01

Results are presented from the application of an emerging Integrated Flight/Propulsion Control (IFPC) design methodology to a Short Take Off and Vertical Landing (STOVL) aircraft in transition flight. The steps in the methodology consist of designing command shaping prefilters to provide the overall desired response to pilot command inputs. A previously designed centralized controller is first validated for the integrated airframe/engine plant used. This integrated plant is derived from a different model of the engine subsystem than the one used for the centralized controller design. The centralized controller is then partitioned in a decentralized, hierarchical structure comprising of airframe lateral and longitudinal subcontrollers and an engine subcontroller. Command shaping prefilters from the pilot control effector inputs are then designed and time histories of the closed loop IFPC system response to simulated pilot commands are compared to desired responses based on handling qualities requirements. Finally, the propulsion system safety and nonlinear limited protection logic is wrapped around the engine subcontroller and the response of the closed loop integrated system is evaluated for transients that encounter the propulsion surge margin limit.

Hospital inpatient self-administration of medicine programmes: a critical literature review.

PubMed

Wright, Julia; Emerson, Angela; Stephens, Martin; Lennan, Elaine

2006-06-01

The Department of Health, pharmaceutical and nursing bodies have advocated the benefits of self-administration programmes (SAPs), but their implementation within UK hospitals has been limited. Perceived barriers are: anticipated increased workload, insufficient resources and patient safety concerns. This review aims to discover if benefits of SAPs are supported in the literature in relation to risk and resource implications. Electronic databases were searched up to March 2004. Published English language articles that described and evaluated implementation of an SAP were included. Outcomes reported were: compliance measures, errors, knowledge, patient satisfaction, and nursing and pharmacy time. Most of the 51 papers reviewed had methodological flaws. SAPs varied widely in content and structure. Twelve studies (10 controlled) measured compliance by tablet counts. Of 7 studies subjected to statistical analysis, four demonstrated a significant difference in compliance between SAP and controls. Eight studies (5 controlled) measured errors as an outcome. Of the two evaluated statistically, only one demonstrated significantly fewer medication errors in the SAP group than in controls. Seventeen papers (11 controlled) studied the effect of SAPs on patients' medication knowledge. Ten of the 11 statistically analysed studies showed that SAP participants knew significantly more about some aspects of their medication than did controls. Seventeen studies (5 controlled), measured patient satisfaction. Two studies were statistically analysed and these studies suggested that patients were satisfied and preferred SAP. Seven papers studied pharmacy time, three studied nursing time but results were not compared to controls. The paucity of well-designed studies, flawed methodology and inadequate reporting in many papers make conclusions hard to draw. Conclusive evidence that SAPs improve compliance was not provided. Although patients participating in SAPs make errors, small numbers of patients are often responsible for a large number of errors. Whilst most studies suggest that SAPs increase patient's knowledge in part, it is difficult to separate out the effect of the educational component of many SAPs. Most patients who participated in SAPs were satisfied with their care and many would choose to take part in a SAP in the future. No studies measured the total resource requirement of implementing and maintaining a SAP.

Robust Feedback Control of Flow Induced Structural Radiation of Sound

NASA Technical Reports Server (NTRS)

Heatwole, Craig M.; Bernhard, Robert J.; Franchek, Matthew A.

1997-01-01

A significant component of the interior noise of aircraft and automobiles is a result of turbulent boundary layer excitation of the vehicular structure. In this work, active robust feedback control of the noise due to this non-predictable excitation is investigated. Both an analytical model and experimental investigations are used to determine the characteristics of the flow induced structural sound radiation problem. The problem is shown to be broadband in nature with large system uncertainties associated with the various operating conditions. Furthermore the delay associated with sound propagation is shown to restrict the use of microphone feedback. The state of the art control methodologies, IL synthesis and adaptive feedback control, are evaluated and shown to have limited success for solving this problem. A robust frequency domain controller design methodology is developed for the problem of sound radiated from turbulent flow driven plates. The control design methodology uses frequency domain sequential loop shaping techniques. System uncertainty, sound pressure level reduction performance, and actuator constraints are included in the design process. Using this design method, phase lag was added using non-minimum phase zeros such that the beneficial plant dynamics could be used. This general control approach has application to lightly damped vibration and sound radiation problems where there are high bandwidth control objectives requiring a low controller DC gain and controller order.

Efficacy of surgery for rotator cuff tendinopathy: a systematic review.

PubMed

Toliopoulos, Panagiota; Desmeules, François; Boudreault, Jennifer; Roy, Jean-Sébastien; Frémont, Pierre; MacDermid, Joy C; Dionne, Clermont E

2014-01-01

The objective of this study is to review randomized controlled trials evaluating the efficacy of surgery for the treatment of rotator cuff (RC) tendinopathy. Studies up to August 2013 were located in the PubMed, Embase, CINAHL, and PEDro databases using relevant keywords. Studies were included if: (1) participants had rotator cuff tendinopathy, (2) the trials were conducted on an adult population (≥18 years old), (3) at least one of the interventions studied was a surgical procedure, (4) study design was a randomized controlled trial (RCT), and (5) the article was written in English or French. Characteristics of the included studies were extracted using a standardized form. Two independent raters reviewed the methodological quality of the studies using the Risk of Bias Assessment tool developed by the Cochrane Collaboration Group. Differences were resolved by consensus. Fifteen trials met our inclusion criteria. After consensus, the mean methodological quality for all studies was 58.9 ± 10.8 %. In three out of four RCTs of moderate or low methodological quality, no significant difference in treatment effectiveness was observed between open or arthroscopic acromioplasty compared to exercises in the treatment of RC tendinopathy. Based on two studies of low or moderate methodological quality, no difference in treatment effectiveness was observed between arthroscopic and open acromioplasty. Two other RCTs of low to moderate quality, however, found that arthroscopic acromioplasty yielded better results in the short-term for shoulder range of motion in flexion but that both procedures were comparable in the long-term. One additional study favored open acromioplasty over arthroscopic acromioplasty for the treatment of RC tendinopathy. Based on low- to moderate-quality evidence, acromioplasty, be it open or arthroscopic, is no more effective than exercises for the treatment of RC tendinopathy. Low-grade evidence also suggests that arthroscopic acromioplasty may yield better results in the short-term for shoulder range of motion in flexion compared to open acromioplasty, but long-term results are comparable between the two types of surgery. More high-quality RCTs are required in order to provide comprehensive treatment guidelines to healthcare providers.

Control technology for future aircraft propulsion systems

NASA Technical Reports Server (NTRS)

Zeller, J. R.; Szuch, J. R.; Merrill, W. C.; Lehtinen, B.; Soeder, J. F.

1984-01-01

The need for a more sophisticated engine control system is discussed. The improvements in better thrust-to-weight ratios demand the manipulation of more control inputs. New technological solutions to the engine control problem are practiced. The digital electronic engine control (DEEC) system is a step in the evolution to digital electronic engine control. Technology issues are addressed to ensure a growth in confidence in sophisticated electronic controls for aircraft turbine engines. The need of a control system architecture which permits propulsion controls to be functionally integrated with other aircraft systems is established. Areas of technology studied include: (1) control design methodology; (2) improved modeling and simulation methods; and (3) implementation technologies. Objectives, results and future thrusts are summarized.

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

Strategy for design NIR calibration sets based on process spectrum and model space: An innovative approach for process analytical technology.

PubMed

Cárdenas, V; Cordobés, M; Blanco, M; Alcalà, M

2015-10-10

The pharmaceutical industry is under stringent regulations on quality control of their products because is critical for both, productive process and consumer safety. According to the framework of "process analytical technology" (PAT), a complete understanding of the process and a stepwise monitoring of manufacturing are required. Near infrared spectroscopy (NIRS) combined with chemometrics have lately performed efficient, useful and robust for pharmaceutical analysis. One crucial step in developing effective NIRS-based methodologies is selecting an appropriate calibration set to construct models affording accurate predictions. In this work, we developed calibration models for a pharmaceutical formulation during its three manufacturing stages: blending, compaction and coating. A novel methodology is proposed for selecting the calibration set -"process spectrum"-, into which physical changes in the samples at each stage are algebraically incorporated. Also, we established a "model space" defined by Hotelling's T(2) and Q-residuals statistics for outlier identification - inside/outside the defined space - in order to select objectively the factors to be used in calibration set construction. The results obtained confirm the efficacy of the proposed methodology for stepwise pharmaceutical quality control, and the relevance of the study as a guideline for the implementation of this easy and fast methodology in the pharma industry. Copyright © 2015 Elsevier B.V. All rights reserved.

Hypnotherapy for insomnia: a systematic review and meta-analysis of randomized controlled trials.

PubMed

Lam, Tak-Ho; Chung, Ka-Fai; Yeung, Wing-Fai; Yu, Branda Yee-Man; Yung, Kam-Ping; Ng, Tommy Ho-Yee

2015-10-01

To examine the efficacy and safety of hypnotherapy for insomnia as compared to placebo, pharmacological or non-pharmacological intervention, or no treatment. A systematic search on major electronic databases was conducted up until March 2014. Inclusion criteria are: (1) randomized controlled trials (RCTs) or quasi-RCTs; (2) intervention targeted at improving sleep; (3) hypnosis as an intervention; and (4) English language articles. Sleep diary variable is the primary outcome measure. Six RCTs of hypnotherapy and seven on autogenic training or guided imagery, comprising 502 subjects, were included. Eleven of the 13 studies had low methodological quality, as indicated by a modified Jadad score below 3, and high risks of bias in blinding and design of the control interventions. No adverse events related to hypnosis were reported, though seldom investigated. Meta-analyses found hypnotherapy significantly shortened sleep latency compared to waitlist (standardized mean difference, SMD=-0.88, 95% confidence interval (CI): -1.56, -0.19, P=0.01, I(2)=15%), but no difference compared to sham intervention (SMD: -1.08, 95% CI: -3.15, 0.09, P=0.31, I(2)=90%). Similar results were found for autogenic training or guided imagery (SMD with waitlist=-1.16, 95% CI: -1.92, -0.40, P=0.003, I(2)=0%; SMD with sham intervention=-0.50, 95% CI: -1.19, 0.19, P=0.15, I(2)=0%). Generalizability of the positive results is doubtful due to the relatively small sample size and methodological limitations. Future studies with larger sample size and better study design and methodology are called for. Copyright © 2015 Elsevier Ltd. All rights reserved.

Risk of unintentional injuries in children and adolescents with ADHD and the impact of ADHD medications: A systematic review and meta-analysis.

PubMed

Ruiz-Goikoetxea, Maite; Cortese, Samuele; Aznarez-Sanado, Maite; Magallón, Sara; Alvarez Zallo, Noelia; Luis, Elkin O; de Castro-Manglano, Pilar; Soutullo, Cesar; Arrondo, Gonzalo

2018-01-01

A systematic review with meta-analyses was performed to: 1) quantify the association between ADHD and risk of unintentional physical injuries in children/adolescents ("risk analysis"); 2) assess the effect of ADHD medications on this risk ("medication analysis"). We searched 114 databases through June 2017. For the risk analysis, studies reporting sex-controlled odds ratios (ORs) or hazard ratios (HRs) estimating the association between ADHD and injuries were combined. Pooled ORs (28 studies, 4,055,620 individuals without and 350,938 with ADHD) and HRs (4 studies, 901,891 individuals without and 20,363 with ADHD) were 1.53 (95% CI=1.40,1.67) and 1.39 (95% CI=1.06,1.83), respectively. For the medication analysis, we meta-analysed studies that avoided the confounding-by-indication bias [four studies with a self-controlled methodology and another comparing risk over time and groups (a "difference in differences" methodology)]. The pooled effect size was 0.879 (95% CI=0.838,0.922) (13,254 individuals with ADHD). ADHD is significantly associated with an increased risk of unintentional injuries and ADHD medications have a protective effect, at least in the short term, as indicated by self-controlled studies. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Does pelvic floor muscle training improve female sexual function? A systematic review.

PubMed

Ferreira, Cristine Homsi Jorge; Dwyer, Peter L; Davidson, Melissa; De Souza, Alison; Ugarte, Julio Alvarez; Frawley, Helena C

2015-12-01

We performed a review of the literature reporting on the effects of pelvic floor muscle training (PFMT) on female sexual function (SF). Pubmed (from 1946 to December 2014), Ovid Medline (from 1946 to December 2014), CINAHL (from 1937 to December 2014), PsycINFO (from 1805 to December 2014), Scopus and Cochrane Central Register of Controlled Trials were searched by two independent reviewers. Randomised controlled trials (RCTs) investigating the impact of PFMT on women's SF published in English were included. Methodological quality was scored using the PEDro scale. Data were analysed qualitatively and interpreted. A total of 1341 women were included in the eight RCTs covered by this review. The studies were published between 1997 and 2014. Methodological scores were between 4 and 7. The sample included derived from heterogeneous populations of women. In only one study was SF the primary outcome measure. Pelvic floor dysfunction was an inclusion criterion in the majority of studies. Most studies reported a significant improvement in SF score after PFMT between control and intervention groups. Although most studies indicated an improvement of at least one sexual variable in women with pelvic floor dysfunction, and one study demonstrated an improvement in SF in postpartum women selected independently of their continence status, the results need to be interpreted with caution. High-quality RCTs specifically designed to investigate the impact of PFMT on women's SF are required.

Problem solving using soft systems methodology.

PubMed

Land, L

This article outlines a method of problem solving which considers holistic solutions to complex problems. Soft systems methodology allows people involved in the problem situation to have control over the decision-making process.

Combining epidemiology and biomechanics in sports injury prevention research: a new approach for selecting suitable controls.

PubMed

Finch, Caroline F; Ullah, Shahid; McIntosh, Andrew S

2011-01-01

Several important methodological issues need to be considered when designing sports injury case-control studies. Major design goals for case-control studies include the accounting for prior injury risk exposure, and optimal definitions of both cases and suitable controls are needed to ensure this. This article reviews methodological aspects of published sports injury case-control studies, particularly with regard to the selection of controls. It argues for a new approach towards selecting controls for case-control studies that draws on an interface between epidemiological and biomechanical concepts. A review was conducted to identify sport injury case-control studies published in the peer-review literature during 1985-2008. Overall, 32 articles were identified, of which the majority related to upper or lower extremity injuries. Matching considerations were used for control selection in 16 studies. Specific mention of application of biomechanical principles in the selection of appropriate controls was absent from all studies, including those purporting to evaluate the benefits of personal protective equipment to protect against impact injury. This is a problem because it could lead to biased conclusions, as cases and controls are not fully comparable in terms of similar biomechanical impact profiles relating to the injury incident, such as site of the impact on the body. The strength of the conclusions drawn from case-control studies, and the extent to which results can be generalized, is directly influenced by the definition and recruitment of cases and appropriate controls. Future studies should consider the interface between epidemiological and biomechanical concepts when choosing appropriate controls to ensure that proper adjustment of prior exposure to injury risk is made. To provide necessary guidance for the optimal selection of controls in case-control studies of interventions to prevent sports-related impact injury, this review outlines a new case-control selection strategy that reflects the importance of biomechanical considerations, which ensures that controls are selected based on the presence of the same global injury mechanism as the cases. To summarize, the general biomechanical principles that should apply to the selection of controls in future case-control studies are as follows: (i) each control must have been exposed to the same global injury mechanism as the case, (e.g. head impact, fall onto outstretched arm); and (ii) intrinsic (individual) factors (e.g. age, sex, skill level) that might modify the person's response to the relevant biomechanical loads are adjusted when either selecting the controls or are in the analysis phase. The same considerations for control selection apply to other study designs such as matched cohort studies or case-crossover studies.

Implementation and Evaluation of Multiple Adaptive Control Technologies for a Generic Transport Aircraft Simulation

NASA Technical Reports Server (NTRS)

Campbell, Stefan F.; Kaneshige, John T.; Nguyen, Nhan T.; Krishakumar, Kalmanje S.

2010-01-01

Presented here is the evaluation of multiple adaptive control technologies for a generic transport aircraft simulation. For this study, seven model reference adaptive control (MRAC) based technologies were considered. Each technology was integrated into an identical dynamic-inversion control architecture and tuned using a methodology based on metrics and specific design requirements. Simulation tests were then performed to evaluate each technology s sensitivity to time-delay, flight condition, model uncertainty, and artificially induced cross-coupling. The resulting robustness and performance characteristics were used to identify potential strengths, weaknesses, and integration challenges of the individual adaptive control technologies

Efficacy of exercise therapy in workers with rotator cuff tendinopathy: a systematic review

PubMed Central

Desmeules, François; Boudreault, Jennifer; Dionne, Clermont E.; Frémont, Pierre; Lowry, Véronique; MacDermid, Joy C.; Roy, Jean-Sébastien

2016-01-01

Objective: To perform a systematic review of randomized controlled trials (RCTs) on the efficacy of therapeutic exercises for workers suffering from rotator cuff (RC) tendinopathy. Methods: A literature search in four bibliographical databases (Pubmed, CINAHL, EMBASE, and PEDro) was conducted from inception up to February 2015. RCTs were included if participants were workers suffering from RC tendinopathy, the outcome measures included work-related outcomes, and at least one of the interventions under study included exercises. The methodological quality of the studies was evaluated with the Cochrane Risk of Bias Assessment tool. Results: The mean methodological score of the ten included studies was 54.4%±17.2%. Types of workers included were often not defined, and work-related outcome measures were heterogeneous and often not validated. Three RCTs of moderate methodological quality concluded that exercises were superior to a placebo or no intervention in terms of function and return-to-work outcomes. No significant difference was found between surgery and exercises based on the results of two studies of low to moderate methodological quality. One study of low methodological quality, comparing a workplace-based exercise program focusing on the participants' work demands to an exercise program delivered in a clinical setting, concluded that the work-based intervention was superior in terms of function and return-to-work outcomes. Conclusion: There is low to moderate-grade evidence that therapeutic exercises provided in a clinical setting are an effective modality to treat workers suffering from RC tendinopathy and to promote return-to-work. Further high quality studies comparing different rehabilitation programs including exercises in different settings with defined workers populations are needed to draw firm conclusions on the optimal program to treat workers. PMID:27488037

Efficacy of exercise therapy in workers with rotator cuff tendinopathy: a systematic review.

PubMed

Desmeules, François; Boudreault, Jennifer; Dionne, Clermont E; Frémont, Pierre; Lowry, Véronique; MacDermid, Joy C; Roy, Jean-Sébastien

2016-09-30

To perform a systematic review of randomized controlled trials (RCTs) on the efficacy of therapeutic exercises for workers suffering from rotator cuff (RC) tendinopathy. A literature search in four bibliographical databases (Pubmed, CINAHL, EMBASE, and PEDro) was conducted from inception up to February 2015. RCTs were included if participants were workers suffering from RC tendinopathy, the outcome measures included work-related outcomes, and at least one of the interventions under study included exercises. The methodological quality of the studies was evaluated with the Cochrane Risk of Bias Assessment tool. The mean methodological score of the ten included studies was 54.4%±17.2%. Types of workers included were often not defined, and work-related outcome measures were heterogeneous and often not validated. Three RCTs of moderate methodological quality concluded that exercises were superior to a placebo or no intervention in terms of function and return-to-work outcomes. No significant difference was found between surgery and exercises based on the results of two studies of low to moderate methodological quality. One study of low methodological quality, comparing a workplace-based exercise program focusing on the participants' work demands to an exercise program delivered in a clinical setting, concluded that the work-based intervention was superior in terms of function and return-to-work outcomes. There is low to moderate-grade evidence that therapeutic exercises provided in a clinical setting are an effective modality to treat workers suffering from RC tendinopathy and to promote return-to-work. Further high quality studies comparing different rehabilitation programs including exercises in different settings with defined workers populations are needed to draw firm conclusions on the optimal program to treat workers.

Methodological factors conducting research with incarcerated persons with diabetes.

PubMed

Reagan, Louise; Shelton, Deborah

2016-02-01

The aim of this study was to describe methodological issues specific to conducting research with incarcerated vulnerable populations who have diabetes. Much has been written about the ethical and logistical challenges of conducting research with vulnerable incarcerated populations. However, conducting research with incarcerated persons with diabetes is associated with additional issues related to research design, measurement, sampling and recruitment, and data collection procedures. A cross-sectional study examining the relationships of diabetes knowledge, illness representation and self-care behaviors with glycemic control in 124 incarcerated persons was conducted and serves as the basis for describing methodological factors for the conduct of research with an incarcerated population with diabetes. Within this incarcerated population with diabetes, sampling bias due to gender inequity, recruitment of participants not using insulin, self-reported vision impairment, and a lack of standardized instruments especially for measuring diabetes self-care were methodological challenges. Clinical factors that serve as potential barriers for study conduct were identified as risk for hypoglycemia due to insulin timing and other activities. Conducting research with incarcerated persons diagnosed with diabetes requires attention to a set of methodological concerns above and beyond that of the ethical and legal regulations for protecting the rights of this vulnerable population. To increase opportunities for conducting rigorous as well as facility- and patient-friendly research, researchers need to blend their knowledge of diabetes with an understanding of prison rules and routines. Copyright © 2015 Elsevier Inc. All rights reserved.

A numerical and experimental study on optimal design of multi-DOF viscoelastic supports for passive vibration control in rotating machinery

NASA Astrophysics Data System (ADS)

Ribeiro, Eduardo Afonso; Lopes, Eduardo Márcio de Oliveira; Bavastri, Carlos Alberto

2017-12-01

Viscoelastic materials have played an important role in passive vibration control. Nevertheless, the use of such materials in supports of rotating machines, aiming at controlling vibration, is more recent, mainly when these supports present additional complexities like multiple degrees of freedom and require accurate models to predict the dynamic behavior of viscoelastic materials working in a broad band of frequencies and temperatures. Previously, the authors propose a methodology for an optimal design of viscoelastic supports (VES) for vibration suppression in rotordynamics, which improves the dynamic prediction accuracy, the speed calculation, and the modeling of VES as complex structures. However, a comprehensive numerical study of the dynamics of rotor-VES systems, regarding the types and combinations of translational and rotational degrees of freedom (DOFs), accompanied by the corresponding experimental validation, is still lacking. This paper presents such a study considering different types and combinations of DOFs in addition to the simulation of their number of additional masses/inertias, as well as the kind and association of the applied viscoelastic materials (VEMs). The results - regarding unbalance frequency response, transmissibility and displacement due to static loads - lead to: 1) considering VES as complex structures which allow improving the efficacy in passive vibration control; 2) acknowledging the best configuration concerning DOFs and VEM choice and association for a practical application concerning passive vibration control and load resistance. The specific outcomes of the conducted experimental validation attest the accuracy of the proposed methodology.

[Development of New Mathematical Methodology in Air Traffic Control for the Analysis of Hybrid Systems

NASA Technical Reports Server (NTRS)

Hermann, Robert

1997-01-01

The aim of this research is to develop new mathematical methodology for the analysis of hybrid systems of the type involved in Air Traffic Control (ATC) problems. Two directions of investigation were initiated. The first used the methodology of nonlinear generalized functions, whose mathematical foundations were initiated by Colombeau and developed further by Oberguggenberger; it has been extended to apply to ordinary differential. Systems of the type encountered in control in joint work with the PI and M. Oberguggenberger. This involved a 'mixture' of 'continuous' and 'discrete' methodology. ATC clearly involves mixtures of two sorts of mathematical problems: (1) The 'continuous' dynamics of a standard control type described by ordinary differential equations (ODE) of the form: {dx/dt = f(x, u)} and (2) the discrete lattice dynamics involved of cellular automata. Most of the CA literature involves a discretization of a partial differential equation system of the type encountered in physics problems (e.g. fluid and gas problems). Both of these directions requires much thinking and new development of mathematical fundamentals before they may be utilized in the ATC work. Rather than consider CA as 'discretization' of PDE systems, I believe that the ATC applications will require a completely different and new mathematical methodology, a sort of discrete analogue of jet bundles and/or the sheaf-theoretic techniques to topologists. Here too, I have begun work on virtually 'virgin' mathematical ground (at least from an 'applied' point of view) which will require considerable preliminary work.

A Systematic Review of Information and Communication Technology–Based Interventions for Promoting Physical Activity Behavior Change in Children and Adolescents

PubMed Central

Lau, Erica Y; Wong, Del P; Ransdell, Lynda

2011-01-01

Background A growing body of research has employed information and communication technologies (ICTs) such as the Internet and mobile phones for disseminating physical activity (PA) interventions with young populations. Although several systematic reviews have documented the effects of ICT-based interventions on PA behavior, very few have focused on children and adolescents specifically. Objectives The present review aimed to systematically evaluate the efficacy and methodological quality of ICT-based PA interventions for children and adolescents based on evidence from randomized controlled trials. Methods Electronic databases Medline, PsycInfo, CINAHL, and Web of Science were searched to retrieve English language articles published in international academic peer-reviewed journals from January 1, 1997, through December 31, 2009. Included were articles that provided descriptions of interventions designed to improve PA-related cognitive, psychosocial, and behavioral outcomes and that used randomized controlled trial design, included only children (6-12 years old) and adolescents (13-18 years old) in both intervention and control groups, and employed Internet, email, and/or short message services (SMS, also known as text messaging) as one or more major or assistive modes to deliver the intervention. Results In total, 9 studies were analyzed in the present review. All studies were published after 2000 and conducted in Western countries. Of the 9 studies, 7 demonstrated positive and significant within-group differences in at least one psychosocial or behavioral PA outcome. In all, 3 studies reported positive and significant between-group differences favoring the ICT group. When between-group differences were compared across studies, effect sizes were small in 6 studies and large in 3 studies. With respect to methodological quality, 7 of the 9 studies had good methodological quality. Failure to report allocation concealment, blinding to outcome assessment, and lack of long-term follow-up were the criteria met by the fewest studies. In addition, 5 studies measured the intervention exposure rate and only 1 study employed objective measures to record data. Conclusion The present review provides evidence supporting the positive effects of ICTs in PA interventions for children and adolescents, especially when used with other delivery approaches (ie, face-to-face). Because ICT delivery approaches are often mixed with other approaches and these studies sometimes lack a comparable control group, additional research is needed to establish the true independent effects of ICT as an intervention delivery mode. Although two-thirds of the studies demonstrated satisfactory methodological quality, several quality criteria should be considered in future studies: clear descriptions of allocation concealment and blinding of outcome assessment, extension of intervention duration, and employment of objective measures in intervention exposure rate. Due to the small number of studies that met inclusion criteria and the lack of consistent evidence, researchers should be cautious when interpreting the findings of the present review. PMID:21749967

A systematic review of information and communication technology-based interventions for promoting physical activity behavior change in children and adolescents.

PubMed

Lau, Patrick W C; Lau, Erica Y; Wong, Del P; Ransdell, Lynda

2011-07-13

A growing body of research has employed information and communication technologies (ICTs) such as the Internet and mobile phones for disseminating physical activity (PA) interventions with young populations. Although several systematic reviews have documented the effects of ICT-based interventions on PA behavior, very few have focused on children and adolescents specifically. The present review aimed to systematically evaluate the efficacy and methodological quality of ICT-based PA interventions for children and adolescents based on evidence from randomized controlled trials. Electronic databases Medline, PsycInfo, CINAHL, and Web of Science were searched to retrieve English language articles published in international academic peer-reviewed journals from January 1, 1997, through December 31, 2009. Included were articles that provided descriptions of interventions designed to improve PA-related cognitive, psychosocial, and behavioral outcomes and that used randomized controlled trial design, included only children (6-12 years old) and adolescents (13-18 years old) in both intervention and control groups, and employed Internet, email, and/or short message services (SMS, also known as text messaging) as one or more major or assistive modes to deliver the intervention. In total, 9 studies were analyzed in the present review. All studies were published after 2000 and conducted in Western countries. Of the 9 studies, 7 demonstrated positive and significant within-group differences in at least one psychosocial or behavioral PA outcome. In all, 3 studies reported positive and significant between-group differences favoring the ICT group. When between-group differences were compared across studies, effect sizes were small in 6 studies and large in 3 studies. With respect to methodological quality, 7 of the 9 studies had good methodological quality. Failure to report allocation concealment, blinding to outcome assessment, and lack of long-term follow-up were the criteria met by the fewest studies. In addition, 5 studies measured the intervention exposure rate and only 1 study employed objective measures to record data. The present review provides evidence supporting the positive effects of ICTs in PA interventions for children and adolescents, especially when used with other delivery approaches (ie, face-to-face). Because ICT delivery approaches are often mixed with other approaches and these studies sometimes lack a comparable control group, additional research is needed to establish the true independent effects of ICT as an intervention delivery mode. Although two-thirds of the studies demonstrated satisfactory methodological quality, several quality criteria should be considered in future studies: clear descriptions of allocation concealment and blinding of outcome assessment, extension of intervention duration, and employment of objective measures in intervention exposure rate. Due to the small number of studies that met inclusion criteria and the lack of consistent evidence, researchers should be cautious when interpreting the findings of the present review.

Effectiveness of Interventions for Prevention of Road Traffic Injuries in Iran and Some Methodological Issues: A Systematic Review.

PubMed

Azami-Aghdash, Saber; Sadeghi-Bazarghani, Homayoun; Heydari, Mahdiyeh; Rezapour, Ramin; Derakhshani, Naser

2018-04-01

To review the effectiveness of Road Traffic Injuries (RTIs) interventions implemented for prevention of RTIs in Iran and to introduce some methodological issues. Required data in this systematic review study were collected through searching the following key words: "Road Traffic Injuries", "Road Traffic accidents", "Road Traffic crashes", "prevention", and Iran in PubMed, Cochrane Library electronic databases, Google Scholar, Scopus, MagIran, SID and IranMedex. Some of the relevant journals and web sites searched manually. Reference lists of the selected articles were also checked. Gray literature search and expert contact was also conducted. Out of 569 retrieved articles, finally 8 articles included. Among the included studies the effectiveness of 10 interventions were assessed containing: seat belt, enforcements of laws and legislations, educational program, wearing helmet, Antilock Braking System (ABS), motorcyclists' penalty enforcement, pupil liaisons' education, provisional driver licensing, Road bumps and traffic improvement's plans. In 7 studies (9 interventions) reduction of RTIs rate were reported. Decreased rate of mortality from RTIs were reported in three studies. Only one study had mentioned financial issue (Anti-lock Brake System intervention). Inadequate data sources, inappropriate selection of statistical index and not mention about the control of Confounding Variables (CV), the most common methodological issues were. The results of most interventional studies conducted in Iran supported the effect of the interventions on reduction of RTIs. However due to some methodological or reporting shortcoming the results of these studies should be interpreted cautiously.

Methodological and Ethical Challenges in a Web-Based Randomized Controlled Trial of a Domestic Violence Intervention

PubMed Central

Valpied, Jodie; Koziol-McLain, Jane; Glass, Nancy; Hegarty, Kelsey

2017-01-01

The use of Web-based methods to deliver and evaluate interventions is growing in popularity, particularly in a health care context. They have shown particular promise in responding to sensitive or stigmatized issues such as mental health and sexually transmitted infections. In the field of domestic violence (DV), however, the idea of delivering and evaluating interventions via the Web is still relatively new. Little is known about how to successfully navigate several challenges encountered by the researchers while working in this area. This paper uses the case study of I-DECIDE, a Web-based healthy relationship tool and safety decision aid for women experiencing DV, developed in Australia. The I-DECIDE website has recently been evaluated through a randomized controlled trial, and we outline some of the methodological and ethical challenges encountered during recruitment, retention, and evaluation. We suggest that with careful consideration of these issues, randomized controlled trials can be safely conducted via the Web in this sensitive area. PMID:28351830

Performance Optimization Control of ECH using Fuzzy Inference Application

NASA Astrophysics Data System (ADS)

Dubey, Abhay Kumar

Electro-chemical honing (ECH) is a hybrid electrolytic precision micro-finishing technology that, by combining physico-chemical actions of electro-chemical machining and conventional honing processes, provides the controlled functional surfaces-generation and fast material removal capabilities in a single operation. Process multi-performance optimization has become vital for utilizing full potential of manufacturing processes to meet the challenging requirements being placed on the surface quality, size, tolerances and production rate of engineering components in this globally competitive scenario. This paper presents an strategy that integrates the Taguchi matrix experimental design, analysis of variances and fuzzy inference system (FIS) to formulate a robust practical multi-performance optimization methodology for complex manufacturing processes like ECH, which involve several control variables. Two methodologies one using a genetic algorithm tuning of FIS (GA-tuned FIS) and another using an adaptive network based fuzzy inference system (ANFIS) have been evaluated for a multi-performance optimization case study of ECH. The actual experimental results confirm their potential for a wide range of machining conditions employed in ECH.

Paratransgenic Control of Vector Borne Diseases

PubMed Central

Hurwitz, Ivy; Fieck, Annabeth; Read, Amber; Hillesland, Heidi; Klein, Nichole; Kang, Angray; Durvasula, Ravi

2011-01-01

Conventional methodologies to control vector borne diseases with chemical pesticides are often associated with environmental toxicity, adverse effects on human health and the emergence of insect resistance. In the paratransgenic strategy, symbiotic or commensal microbes of host insects are transformed to express gene products that interfere with pathogen transmission. These genetically altered microbes are re-introduced back to the insect where expression of the engineered molecules decreases the host's ability to transmit the pathogen. We have successfully utilized this strategy to reduce carriage rates of Trypanosoma cruzi, the causative agent of Chagas disease, in the triatomine bug, Rhodnius prolixus, and are currently developing this methodology to control the transmission of Leishmania donovani by the sand fly Phlebotomus argentipes. Several effector molecules, including antimicrobial peptides and highly specific single chain antibodies, are currently being explored for their anti-parasite activities in these two systems. In preparation for eventual field use, we are actively engaged in risk assessment studies addressing the issue of horizontal gene transfer from the modified bacteria to environmental microbes. PMID:22110385

An Adaptive Control Technology for Safety of a GTM-like Aircraft

NASA Technical Reports Server (NTRS)

Matsutani, Megumi; Crespo, Luis G.; Annaswamy, Anuradha; Jang, Jinho

2010-01-01

An adaptive control architecture for safe performance of a transport aircraft subject to various adverse conditions is proposed and verified in this report. This architecture combines a nominal controller based on a Linear Quadratic Regulator with integral action, and an adaptive controller that accommodates actuator saturation and bounded disturbances. The effectiveness of the baseline controller and its adaptive augmentation are evaluated using a stand-alone control veri fication methodology. Case studies that pair individual parameter uncertainties with critical flight maneuvers are studied. The resilience of the controllers is determined by evaluating the degradation in closed-loop performance resulting from increasingly larger deviations in the uncertain parameters from their nominal values. Symmetric and asymmetric actuator failures, flight upsets, and center of gravity displacements, are some of the uncertainties considered.

Methodological reporting quality of randomized controlled trials: A survey of seven core journals of orthopaedics from Mainland China over 5 years following the CONSORT statement.

PubMed

Zhang, J; Chen, X; Zhu, Q; Cui, J; Cao, L; Su, J

2016-11-01

In recent years, the number of randomized controlled trials (RCTs) in the field of orthopaedics is increasing in Mainland China. However, randomized controlled trials (RCTs) are inclined to bias if they lack methodological quality. Therefore, we performed a survey of RCT to assess: (1) What about the quality of RCTs in the field of orthopedics in Mainland China? (2) Whether there is difference between the core journals of the Chinese department of orthopedics and Orthopaedics Traumatology Surgery & Research (OTSR). This research aimed to evaluate the methodological reporting quality according to the CONSORT statement of randomized controlled trials (RCTs) in seven key orthopaedic journals published in Mainland China over 5 years from 2010 to 2014. All of the articles were hand researched on Chongqing VIP database between 2010 and 2014. Studies were considered eligible if the words "random", "randomly", "randomization", "randomized" were employed to describe the allocation way. Trials including animals, cadavers, trials published as abstracts and case report, trials dealing with subgroups analysis, or trials without the outcomes were excluded. In addition, eight articles selected from Orthopaedics Traumatology Surgery & Research (OTSR) between 2010 and 2014 were included in this study for comparison. The identified RCTs are analyzed using a modified version of the Consolidated Standards of Reporting Trials (CONSORT), including the sample size calculation, allocation sequence generation, allocation concealment, blinding and handling of dropouts. A total of 222 RCTs were identified in seven core orthopaedic journals. No trials reported adequate sample size calculation, 74 (33.4%) reported adequate allocation generation, 8 (3.7%) trials reported adequate allocation concealment, 18 (8.1%) trials reported adequate blinding and 16 (7.2%) trials reported handling of dropouts. In OTSR, 1 (12.5%) trial reported adequate sample size calculation, 4 (50.0%) reported adequate allocation generation, 1 (12.5%) trials reported adequate allocation concealment, 2 (25.0%) trials reported adequate blinding and 5 (62.5%) trials reported handling of dropouts. There were statistical differences as for sample size calculation and handling of dropouts between papers from Mainland China and OTSR (P<0.05). The findings of this study show that the methodological reporting quality of RCTs in seven core orthopaedic journals from the Mainland China is far from satisfaction and it needs to further improve to keep up with the standards of the CONSORT statement. Level III case control. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Study design and "evidence" in patient-oriented research.

PubMed

Concato, John

2013-06-01

Individual studies in patient-oriented research, whether described as "comparative effectiveness" or using other terms, are based on underlying methodological designs. A simple taxonomy of study designs includes randomized controlled trials on the one hand, and observational studies (such as case series, cohort studies, and case-control studies) on the other. A rigid hierarchy of these design types is a fairly recent phenomenon, promoted as a tenet of "evidence-based medicine," with randomized controlled trials receiving gold-standard status in terms of producing valid results. Although randomized trials have many strengths, and contribute substantially to the evidence base in clinical care, making presumptions about the quality of a study based solely on category of research design is unscientific. Both the limitations of randomized trials as well as the strengths of observational studies tend to be overlooked when a priori assumptions are made. This essay presents an argument in support of a more balanced approach to evaluating evidence, and discusses representative examples from the general medical as well as pulmonary and critical care literature. The simultaneous consideration of validity (whether results are correct "internally") and generalizability (how well results apply to "external" populations) is warranted in assessing whether a study's results are accurate for patients likely to receive the intervention-examining the intersection of clinical and methodological issues in what can be called a medicine-based evidence approach. Examination of cause-effect associations in patient-oriented research should recognize both the strengths and limitations of randomized trials as well as observational studies.

Development of a Checklist for Assessing Good Hygiene Practices of Fresh-Cut Fruits and Vegetables Using Focus Group Interviews.

PubMed

Araújo, Jane A M; Esmerino, Erick A; Alvarenga, Verônica O; Cappato, Leandro P; Hora, Iracema C; Silva, Marcia Cristina; Freitas, Monica Q; Pimentel, Tatiana C; Walter, Eduardo H M; Sant'Ana, Anderson S; Cruz, Adriano G

2018-03-01

This study aimed to develop a checklist for good hygiene practices (GHP) for raw material of vegetable origin using the focus groups (FGs) approach (n = 4). The final checklist for commercialization of horticultural products totaled 28 questions divided into six blocks, namely: water supply; hygiene, health, and training; waste control; control of pests; packaging and traceability; and hygiene of facilities and equipment. The FG methodology was efficient to elaborate a participatory and objective checklist, based on minimum hygiene requirements, serving as a tool for diagnosis, planning, and training in GHP of fresh vegetables, besides contributing to raise awareness of the consumers' food safety. The FG methodology provided useful information to establish the final checklist for GHP, with easy application, according to the previous participants' perception and experience.

Does Exercise Improve Cognitive Performance? A Conservative Message from Lord's Paradox

PubMed Central

Liu, Sicong; Lebeau, Jean-Charles; Tenenbaum, Gershon

2016-01-01

Although extant meta-analyses support the notion that exercise results in cognitive performance enhancement, methodology shortcomings are noted among primary evidence. The present study examined relevant randomized controlled trials (RCTs) published in the past 20 years (1996–2015) for methodological concerns arise from Lord's paradox. Our analysis revealed that RCTs supporting the positive effect of exercise on cognition are likely to include Type I Error(s). This result can be attributed to the use of gain score analysis on pretest-posttest data as well as the presence of control group superiority over the exercise group on baseline cognitive measures. To improve accuracy of causal inferences in this area, analysis of covariance on pretest-posttest data is recommended under the assumption of group equivalence. Important experimental procedures are discussed to maintain group equivalence. PMID:27493637

Methodology for a randomised controlled trial of preschool vision screening. A new approach with the 'ALSPAC' project.

PubMed

Williams, C; Harrad, R A; Harvey, I; Frankel, S; Golding, J

1996-06-01

We present the methodology of a population-based Randomised Controlled Trial, comparing an intensive programme of primary preschool vision screening by orthoptists with the usual non-specialist screening. The aims of the trial are to compare the effectiveness and costs of intensive orthoptic screening with non-specialist measures. The orthoptic screening programme will be evaluated both as a composite package and in terms of the screening value of the individual tests at specific ages. This trial is nested within a large population-based longitudinal study. Additional demographic and developmental data on the children in the trial are therefore available. The results of the trial will be used to help clarify which methods of preschool ophthalmic population screening are best in terms of disease detection and cost efficiency.

Using Lean Six Sigma Methodology to Improve Quality of the Anesthesia Supply Chain in a Pediatric Hospital.

PubMed

Roberts, Renée J; Wilson, Ashley E; Quezado, Zenaide

2017-03-01

Six Sigma and Lean methodologies are effective quality improvement tools in many health care settings. We applied the DMAIC methodology (define, measure, analyze, improve, control) to address deficiencies in our pediatric anesthesia supply chain. We defined supply chain problems by mapping existing processes and soliciting comments from those involved. We used daily distance walked by anesthesia technicians and number of callouts for missing supplies as measurements that we analyzed before and after implementing improvements (anesthesia cart redesign). We showed improvement in the metrics after those interventions were implemented, and those improvements were sustained and thus controlled 1 year after implementation.

Past and Ongoing Tsetse and Animal Trypanosomiasis Control Operations in Five African Countries: A Systematic Review

PubMed Central

Holt, Hannah R.; Selby, Richard; Guitian, Javier

2016-01-01

Background Control operations targeting Animal African Trypanosomiasis and its primary vector, the tsetse, were covering approximately 128,000 km2 of Africa in 2001, which is a mere 1.3% of the tsetse infested area. Although extensive trypanosomiasis and tsetse (T&T) control operations have been running since the beginning of the 20th century, Animal African Trypanosomiasis is still a major constraint of livestock production in sub-Saharan Africa. Methodology/Principal Findings We performed a systematic review of the existing literature describing T&T control programmes conducted in a selection of five African countries, namely Burkina Faso, Cameroon, Ethiopia, Uganda and Zambia, between 1980 and 2015. Sixty-eight documents were eventually selected from those identified by the database search. This was supplemented with information gathered through semi-structured interviews conducted with twelve key informants recruited in the study countries and selected based on their experience and knowledge of T&T control. The combined information from these two sources was used to describe the inputs, processes and outcomes from 23 major T&T control programmes implemented in the study countries. Although there were some data gaps, involvement of the target communities and sustainability of the control activities were identified as the two main issues faced by these programmes. Further, there was a lack of evaluation of these control programmes, as well as a lack of a standardised methodology to conduct such evaluations. Conclusions/Significance Past experiences demonstrated that coordinated and sustained control activities require careful planning, and evidence of successes, failures and setbacks from past control programmes represent a mine of information. As there is a lack of evaluation of these programmes, these data have not been fully exploited for the design, analyses and justification of future control programmes. PMID:28027299

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.

Interventions to Promote Physical Activity in Older People with Type 2 Diabetes Mellitus: A Systematic Review

PubMed Central

Sazlina, Shariff-Ghazali; Browning, Colette; Yasin, Shajahan

2013-01-01

Introduction: Type 2 diabetes mellitus (T2DM) among people aged 60 years and above is a growing public health problem. Regular physical activity is one of the key elements in the management of T2DM. Recommendations suggest that older people with T2DM will benefit from regular physical activity for better disease control and delaying complications. Despite the known benefits, many remain sedentary. Hence, this review assessed interventions for promoting physical activity in persons aged 65 years and older with T2DM. Methods: A literature search was conducted using Ovid MEDLINE, PubMed, EMBASE, SPORTDiscus, and CINAHL databases to retrieve articles published between January 2000 and December 2012. Randomized controlled trials and quasi-experimental designs comparing different strategies to increase physical activity level in persons aged 65 years and older with T2DM were included. The methodological quality of studies was assessed. Results: Twenty-one eligible studies were reviewed, only six studies were rated as good quality and only one study specifically targeted persons aged 65 years and older. Personalized coaching, goal setting, peer support groups, use of technology, and physical activity monitors were proven to increase the level of physical activity. Incorporation of health behavior theories and follow-up supports also were successful strategies. However, the methodological quality and type of interventions promoting physical activity of the included studies in this review varied widely across the eligible studies. Conclusion: Strategies that increased level of physical activity in persons with T2DM are evident but most studies focused on middle-aged persons and there was a lack of well-designed trials. Hence, more studies of satisfactory methodological quality with interventions promoting physical activity in older people are required. PMID:24392445

Comparative study on neutronics characteristics of a 1500 MWe metal fuel sodium-cooled fast reactor

DOE PAGES

Ohgama, Kazuya; Aliberti, Gerardo; Stauff, Nicolas E.; ...

2017-02-28

Under the cooperative effort of the Civil Nuclear Energy R&D Working Group within the framework of the U.S.-Japan bilateral, Argonne National Laboratory (ANL) and Japan Atomic Energy Agency (JAEA) have been performing benchmark study using Japan Sodium-cooled Fast Reactor (JSFR) design with metal fuel. In this benchmark study, core characteristic parameters at the beginning of cycle were evaluated by the best estimate deterministic and stochastic methodologies of ANL and JAEA. The results obtained by both institutions show a good agreement with less than 200 pcm of discrepancy on the neutron multiplication factor, and less than 3% of discrepancy on themore » sodium void reactivity, Doppler reactivity, and control rod worth. The results by the stochastic and deterministic approaches were compared in each party to investigate impacts of the deterministic approximation and to understand potential variations in the results due to different calculation methodologies employed. From the detailed analysis of methodologies, it was found that the good agreement in multiplication factor from the deterministic calculations comes from the cancellation of the differences on the methodology (0.4%) and nuclear data (0.6%). The different treatment in reflector cross section generation was estimated as the major cause of the discrepancy between the multiplication factors by the JAEA and ANL deterministic methodologies. Impacts of the nuclear data libraries were also investigated using a sensitivity analysis methodology. Furthermore, the differences on the inelastic scattering cross sections of U-238, ν values and fission cross sections of Pu-239 and µ-average of Na-23 are the major contributors to the difference on the multiplication factors.« less

Comparative study on neutronics characteristics of a 1500 MWe metal fuel sodium-cooled fast reactor

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

Ohgama, Kazuya; Aliberti, Gerardo; Stauff, Nicolas E.

Under the cooperative effort of the Civil Nuclear Energy R&D Working Group within the framework of the U.S.-Japan bilateral, Argonne National Laboratory (ANL) and Japan Atomic Energy Agency (JAEA) have been performing benchmark study using Japan Sodium-cooled Fast Reactor (JSFR) design with metal fuel. In this benchmark study, core characteristic parameters at the beginning of cycle were evaluated by the best estimate deterministic and stochastic methodologies of ANL and JAEA. The results obtained by both institutions show a good agreement with less than 200 pcm of discrepancy on the neutron multiplication factor, and less than 3% of discrepancy on themore » sodium void reactivity, Doppler reactivity, and control rod worth. The results by the stochastic and deterministic approaches were compared in each party to investigate impacts of the deterministic approximation and to understand potential variations in the results due to different calculation methodologies employed. From the detailed analysis of methodologies, it was found that the good agreement in multiplication factor from the deterministic calculations comes from the cancellation of the differences on the methodology (0.4%) and nuclear data (0.6%). The different treatment in reflector cross section generation was estimated as the major cause of the discrepancy between the multiplication factors by the JAEA and ANL deterministic methodologies. Impacts of the nuclear data libraries were also investigated using a sensitivity analysis methodology. Furthermore, the differences on the inelastic scattering cross sections of U-238, ν values and fission cross sections of Pu-239 and µ-average of Na-23 are the major contributors to the difference on the multiplication factors.« less

Feasibility study of using statistical process control to customized quality assurance in proton therapy.

PubMed

Rah, Jeong-Eun; Shin, Dongho; Oh, Do Hoon; Kim, Tae Hyun; Kim, Gwe-Ya

2014-09-01

To evaluate and improve the reliability of proton quality assurance (QA) processes and, to provide an optimal customized tolerance level using the statistical process control (SPC) methodology. The authors investigated the consistency check of dose per monitor unit (D/MU) and range in proton beams to see whether it was within the tolerance level of the daily QA process. This study analyzed the difference between the measured and calculated ranges along the central axis to improve the patient-specific QA process in proton beams by using process capability indices. The authors established a customized tolerance level of ±2% for D/MU and ±0.5 mm for beam range in the daily proton QA process. In the authors' analysis of the process capability indices, the patient-specific range measurements were capable of a specification limit of ±2% in clinical plans. SPC methodology is a useful tool for customizing the optimal QA tolerance levels and improving the quality of proton machine maintenance, treatment delivery, and ultimately patient safety.

Acupuncture and moxibustion for lateral elbow pain: a systematic review of randomized controlled trials

PubMed Central

2014-01-01

Background Acupuncture and moxibustion have widely been used to treat lateral elbow pain (LEP). A comprehensive systematic review of randomized controlled trials (RCTs) including both English and Chinese databases was conducted to assess the efficacy of acupuncture and moxibustion in the treatment of LEP. Methods Revised STRICTA (2010) criteria were used to appraise the acupuncture procedures, the Cochrane risk of bias tool was used to assess the methodological quality of the studies. A total of 19 RCTs that compared acupuncture and/or moxibustion with sham acupuncture, another form of acupuncture, or conventional treatment were included. Results All studies had at least one domain rated as high risk or uncertain risk of bias in the Cochrane risk of bias tool. Results from three RCTs of moderate quality showed that acupuncture was more effective than sham acupuncture. Results from 10 RCTs of mostly low quality showed that acupuncture or moxibustion was superior or equal to conventional treatment, such as local anesthetic injection, local steroid injection, non-steroidal anti- inflammatory drugs, or ultrasound. There were six low quality RCTs that compared acupuncture and moxibustion combined with manual acupuncture alone, and all showed that acupuncture and moxibustion combined was superior to manual acupuncture alone. Conclusion Moderate quality studies suggest that acupuncture is more effective than sham acupuncture. Interpretations of findings regarding acupuncture vs. conventional treatment, and acupuncture and moxibustion combined vs. manual acupuncture alone are limited by the methodological qualities of these studies. Future studies with improved methodological design are warranted to confirm the efficacy of acupuncture and moxibustion for LEP. PMID:24726029

Flight Control Using Distributed Shape-Change Effector Arrays

NASA Technical Reports Server (NTRS)

Raney, David L.; Montgomery, Raymond C.; Green, Lawrence I.; Park, Michael A.

2000-01-01

Recent discoveries in material science and fluidics have been used to create a variety of novel effector devices that offer great potential to enable new approaches to aerospace vehicle flight control. Examples include small inflatable blisters, shape-memory alloy diaphragms, and piezoelectric patches that may be used to produce distortions or bumps on the surface of an airfoil to generate control moments. Small jets have also been used to produce a virtual shape-change through fluidic means by creating a recirculation bubble on the surface of an airfoil. An advanced aerospace vehicle might use distributed arrays of hundreds of such devices to generate moments for stabilization and maneuver control, either augmenting or replacing conventional ailerons, flaps or rudders. This research demonstrates the design and use of shape-change device arrays for a tailless aircraft in a low-rate maneuvering application. A methodology for assessing the control authority of the device arrays is described, and a suite of arrays is used in a dynamic simulation to illustrate allocation and deployment methodologies. Although the authority of the preliminary shape-change array designs studied in this paper appeared quite low, the simulation results indicate that the effector suite possessed sufficient authority to stabilize and maneuver the vehicle in mild turbulence.

Cluster Randomised Trials in Cochrane Reviews: Evaluation of Methodological and Reporting Practice.

PubMed

Richardson, Marty; Garner, Paul; Donegan, Sarah

2016-01-01

Systematic reviews can include cluster-randomised controlled trials (C-RCTs), which require different analysis compared with standard individual-randomised controlled trials. However, it is not known whether review authors follow the methodological and reporting guidance when including these trials. The aim of this study was to assess the methodological and reporting practice of Cochrane reviews that included C-RCTs against criteria developed from existing guidance. Criteria were developed, based on methodological literature and personal experience supervising review production and quality. Criteria were grouped into four themes: identifying, reporting, assessing risk of bias, and analysing C-RCTs. The Cochrane Database of Systematic Reviews was searched (2nd December 2013), and the 50 most recent reviews that included C-RCTs were retrieved. Each review was then assessed using the criteria. The 50 reviews we identified were published by 26 Cochrane Review Groups between June 2013 and November 2013. For identifying C-RCTs, only 56% identified that C-RCTs were eligible for inclusion in the review in the eligibility criteria. For reporting C-RCTs, only eight (24%) of the 33 reviews reported the method of cluster adjustment for their included C-RCTs. For assessing risk of bias, only one review assessed all five C-RCT-specific risk-of-bias criteria. For analysing C-RCTs, of the 27 reviews that presented unadjusted data, only nine (33%) provided a warning that confidence intervals may be artificially narrow. Of the 34 reviews that reported data from unadjusted C-RCTs, only 13 (38%) excluded the unadjusted results from the meta-analyses. The methodological and reporting practices in Cochrane reviews incorporating C-RCTs could be greatly improved, particularly with regard to analyses. Criteria developed as part of the current study could be used by review authors or editors to identify errors and improve the quality of published systematic reviews incorporating C-RCTs.

Towards sustainable mobile systems configurations: Application to a tuna purse seiner.

PubMed

García Rellán, A; Vázquez Brea, C; Bello Bugallo, P M

2018-08-01

Fishing is one of the most important marine activities. It contributes to both overfishing and marine pollution, the two main threats to the ocean environment. In this context, the aim of this work is to investigate and validate methodologies for the identification of more sustainable operating configurations for a tuna purse seiner. The proposed methodology is based on a previous one applied to secondary industrial systems, taking into account the Integrated Pollution Prevention and Control focus, developed for the most potentially industrial polluting sources. The idea is to apply the same type of methodologies and concepts used for secondary industrial punctual sources, to a primary industrial mobile activity. This methodology combines two tools: "Material and Energy Flow Analysis" (a tool from industrial metabolism), and "Best Available Techniques Analysis". The first provides a way to detect "Improvable Flows" into de system, and the second provides a way to define sustainable options to improve them. Five main Improvable Flows have been identified in the selected case study, the activity of a purse seiner, most of them related with energy consumption and air emission, in different stages of the fishing activity. Thirty-one Best Available Techniques candidates for the system have been inventoried, that potentially could improve the sustainability of the activity. Seven of them are not implemented yet to the case study. The potential improvements of the system proposed by this work are related to energy efficiency, waste management, prevention and control of air emissions. This methodology demonstrates to be a good tool towards sustainable punctual systems, but also towards sustainable mobile systems such as the fishing activity in oceans, as the tuna purse seiner validated here. The practical application of the identified technologies to fishing systems will contribute to prevent and reduce marine pollution, one of the greatest threats of today's oceans. Copyright © 2017 Elsevier B.V. All rights reserved.

Translational models of infection prevention and control: lessons from studying high risk aging populations.

PubMed

Mody, Lona

2018-06-13

The present review describes our research experiences and efforts in advancing the field of infection prevention and control in nursing facilities including postacute and long-term care settings. There are over two million infections in postacute and long-term care settings each year in the United States and $4 billion in associated costs. To define a target group most amenable to infection prevention and control interventions, we sought to quantify the relation between indwelling device use and microbial colonization in nursing facility patients. Using various methodologies including survey methods, observational epidemiology, randomized controlled studies, and collaboratives, we showed that indwelling device type is related to the site of multidrug-resistant organism (MDRO) colonization; multianatomic site colonization with MDROs is common; community-associated methicillin-resistant Staphylococcus aureus (MRSA) appeared in the nursing facility setting almost immediately following its emergence in acute care; (4) MDRO prevalence and catheter-associated infection rates can be reduced through a multimodal targeted infection prevention intervention; and (5) using a collaborative approach, such an intervention can be successfully scaled up. Our work advances the infection prevention field through translational research utilizing various methodologies, including quantitative and qualitative surveys, patient-oriented randomized controlled trials, and clinical microbiologic and molecular methods. The resulting interventions employ patient-oriented methods to reduce infections and antimicrobial resistance, and with partnerships from major national entities, can be implemented nationally.

Proceedings of the Seminar on the DOD Computer Security Initiative (4th) Held at the National Bureau of Standards, Gaithersburg, Maryland on August 10-12, 1981.

DTIC Science & Technology

1981-01-01

comparison of formal and informal design methodologies will show how we think they are converging. Lastly, I will describe our involvement with the DoD...computer security must begin with the design methodology , with the objective being provability. The idea ofa formal evaluation and on-the-shelf... Methodologies ] Here we can compare the formal design methodologies with those used by informal practitioners like Control Data. Obviously, both processes

Identifying additional studies for a systematic review of retention strategies in randomised controlled trials: making contact with trials units and trial methodologists.

PubMed

Brueton, Valerie; Tierney, Jayne F; Stenning, Sally; Rait, Greta

2017-08-22

Search strategies for systematic reviews aim to identify all evidence relevant to the research question posed. Reports of methodological research can be difficult to find leading to biased results in systematic reviews of research methodology. Evidence suggests that contact with investigators can help to identify unpublished research. To identify additional eligible randomised controlled trials (RCTs) for a Cochrane systematic review of strategies to improve retention in RCTs, we conducted a survey of UK clinical trials units (CTUs) and made contact with RCT methodologists. Key contacts for all UK CTUs were sent a personalised email with a short questionnaire and summary protocol of the Cochrane methodology review. The questionnaire asked whether a RCT evaluating strategies to improve retention embedded in a RCT had ever been conducted by the CTU. Questions about the stage of completion and publication of such RCTs were included. The summary protocol outlined the aims, eligibility criteria, examples of types of retention strategies, and the primary outcome for the systematic review. Personal communication with RCT methodologists and presentations of preliminary results of the review at conferences were also used to identify additional eligible RCTs. We checked the results of our standard searches to see if eligible studies identified through these additional methods were also found using our standard searches. We identified 14 of the 38 RCTs included in the Cochrane methodology review by contacting trials units and methodologists. Eleven of the 14 RCTs identified by these methods were either published in grey literature, in press or unpublished. Three remaining RCTs were fully published at the time. Six of the RCTs identified were not found through any other searches. The RCTs identified represented data for 6 of 14 RCTs of incentive strategies (52% of randomised participants included in the review), and 6 of 14 RCTs of communication strategies (52% of randomised participants included in the Cochrane review). Data were unavailable for two of the RCTs identified. Methodological evaluations embedded in RCTs may be unpublished, published in the grey literature or where published, poorly indexed in bibliographic databases. To identify such studies and minimise selection bias in systematic reviews of methodological evaluations, reviewers should consider contacting CTUs and trial methodologists.

Development of a methodology for strategic environmental assessment: application to the assessment of golf course installation policy in Taiwan.

PubMed

Chen, Ching-Ho; Wu, Ray-Shyan; Liu, Wei-Lin; Su, Wen-Ray; Chang, Yu-Min

2009-01-01

Some countries, including Taiwan, have adopted strategic environmental assessment (SEA) to assess and modify proposed policies, plans, and programs (PPPs) in the planning phase for pursuing sustainable development. However, there were only some sketchy steps focusing on policy assessment in the system of Taiwan. This study aims to develop a methodology for SEA in Taiwan to enhance the effectiveness associated with PPPs. The proposed methodology comprises an SEA procedure involving PPP management and assessment in various phases, a sustainable assessment framework, and an SEA management system. The SEA procedure is devised based on the theoretical considerations by systems thinking and the regulative requirements in Taiwan. The positive and negative impacts on ecology, society, and economy are simultaneously considered in the planning (including policy generation and evaluation), implementation, and control phases of the procedure. This study used the analytic hierarchy process, Delphi technique, and systems analysis to develop a sustainable assessment framework. An SEA management system was built based on geographic information system software to process spatial, attribute, and satellite image data during the assessment procedure. The proposed methodology was applied in the SEA of golf course installation policy in 2001 as a case study, which was the first SEA in Taiwan. Most of the 82 existing golf courses in 2001 were installed on slope lands and caused a serious ecological impact. Assessment results indicated that 15 future golf courses installed on marginal lands (including buffer zones, remedied lands, and wastelands) were acceptable because the comprehensive environmental (ecological, social, and economic) assessment value was better based on environmental characteristics and management regulations of Taiwan. The SEA procedure in the planning phase for this policy was completed but the implementation phase of this policy was not begun because the related legislation procedure could not be arranged due to a few senators' resistance. A self-review of the control phase was carried out in 2006 using this methodology. Installation permits for 12 courses on slope lands were terminated after 2001 and then 27 future courses could be installed on marginal lands. The assessment value of this policy using the data on ecological, social, and economic conditions from 2006 was higher than that using the data from 2001. The analytical results illustrate that the proposed methodology can be used to effectively and efficiently assist the related authorities for SEA.

Role of Garlic Usage in Cardiovascular Disease Prevention: An Evidence-Based Approach

PubMed Central

Ashfaq, Tabinda

2013-01-01

Introduction. Rapidly growing prevalence of cardiovascular disease is a major threat for the developed as well as developing world warranting urgent need of intervention. Complementary and alternative medicines are gaining popularity among general population because of their safety profile and easy administration. Garlic, in particular, is considered to be one of the best disease-preventive foods because of its potent and widespread effects. This study was done to find out the role of garlic usage in cardiovascular disease prevention. Methodology. Major databases including Google, PubMed, MEDLINE, and Cochrane library view were used for the literature search. Clinical trials conducted on humans assessing role of garlic usage in cardiovascular disease prevention and the possible mechanisms responsible for such therapeutic actions were assessed. Results. Various clinical trials and meta-analyses conducted have shown positive impact of garlic in cardiovascular-disease prevention especially its effects on lipid levels; however, some contradictory results are also reported. Similarly, its effects on hypertension control, and platelet are also mild with limited data availability. The possible reason for these inconsistent results is the difference in preparations with diverse composition, variations in sulphur content present in different garlic preparations used, and methodological variations in subject recruitment, duration of study, dietary control and so forth. Conclusion. Garlic can be used as an adjuvant with lipid-lowering drugs for control of lipids, however, its role as a main therapeutic agent cannot be recommended and it is suggested that more meta-analyses using standardized preparations with a close watch on methodological shortfalls should be conducted to prove its role. PMID:23690831

A systematic review of studies evaluating diffusion and dissemination of selected cancer control interventions.

PubMed

Ellis, Peter; Robinson, Paula; Ciliska, Donna; Armour, Tanya; Brouwers, Melissa; O'Brien, Mary Ann; Sussman, Jonathan; Raina, Parminder

2005-09-01

With this review, the authors sought to determine what strategies have been evaluated (including the outcomes assessed) to disseminate cancer control interventions that promote the uptake of behavior change. Five topic areas along the cancer care continuum (smoking cessation, healthy diet, mammography, cervical cancer screening, and control of cancer pain) were selected to be representative. A systematic review was conducted of primary studies evaluating dissemination of a cancer control intervention. Thirty-one studies were identified that evaluated dissemination strategies in the 5 topic areas. No strong evidence currently exists to recommend any one dissemination strategy as effective in promoting the uptake of cancer control interventions. The authors conclude that there is a strong need for more research into dissemination of cancer control interventions. Future research should consider methodological issues such as the most appropriate study design and outcomes to be evaluated. (c) 2005 APA, all rights reserved

Randomized controlled drug trials on very elderly subjects: descriptive and methodological analysis of trials published between 1990 and 2002 and comparison with trials on adults.

PubMed

Le Quintrec, Jean-Laurent; Bussy, Caroline; Golmard, Jean-Louis; Hervé, Christian; Baulon, Alain; Piette, François

2005-03-01

Very elderly subjects (VES; aged 80 years or older) constitute a special population as they frequently present multiple diseases (polypathology). Results from trials on general adult populations therefore cannot be extrapolated to VES. We performed a census of randomized controlled trials (RCT) on VES published between 1990 and 2002, and carried out a descriptive and methodological analysis of these RCT/VES, comparing them with matched RCT on general adult populations (control RCT, RCT/C). We searched for RCT/VES in two international databases (EMBASE and MEDLINE) and then manually. RCT/C were matched to RCT/VES for disease area and year of publication. The methodological quality of each RCT was assessed with Chalmers' scale. We identified 84 RCT/VES, 63 of which were conclusive and 21, inconclusive. Subjects were institutionalized in 48 RCT, and community dwelling in 11 RCT (unspecified in 25 RCT). Efficacy was the main criterion in 75 RCT; tolerance in 9 RCT. Twenty-six RCT were published by geriatrics journals, and 58 by general medical journals. The RCT/VES covered most of the disease areas of geriatrics. The 84 RCT/VES had a mean methodological quality score of 0.578 +/- 0.157. The matched 84 RCT/C had a mean methodological quality score of 0.592 +/- 0.116 (p = .466). The methodological quality score of RCT/VES increased with the number of included subjects (p = .004) and the year of publication (p = .001). The methodological quality of RCT/VES is equivalent to that of RCT in general adult populations. Nevertheless, RCT/VES remain very scarce, and neglect certain diseases. RCT/VES and the inclusion of very elderly subjects in RCT on adults should be strongly encouraged.

Integrated microreactor for enzymatic reaction automation: An easy step toward the quality control of monoclonal antibodies.

PubMed

Ladner, Yoann; Mas, Silvia; Coussot, Gaelle; Bartley, Killian; Montels, Jérôme; Morel, Jacques; Perrin, Catherine

2017-12-15

The main purpose of the present work is to provide a fully integrated miniaturized electrophoretic methodology in order to facilitate the quality control of monoclonal antibodies (mAbs). This methodology called D-PES, which stands for Diffusion-mediated Proteolysis combined with an Electrophoretic Separation, permits to perform subsequently mAb tryptic digestion and electrophoresis separation of proteolysis products in an automated manner. Tryptic digestion conditions were optimized regarding the influence of enzyme concentration and incubation time in order to achieve similar enzymatic digestion efficiency to that obtained with the classical methodology (off-line). Then, the optimization of electrophoretic separation conditions concerning the nature of background electrolyte (BGE), ionic strength and pH was realized. Successful and repeatable electrophoretic profiles of three mAbs digests (Trastuzumab, Infliximab and Tocilizumab), comparable to the off-line digestion profiles, were obtained demonstrating the feasibility and robustness of the proposed methodology. In summary, the use of the proposed and optimized in-line approach opens a new, fast and easy way for the quality control of mAbs. Copyright © 2017 Elsevier B.V. All rights reserved.

MASQOT: a method for cDNA microarray spot quality control

PubMed Central

Bylesjö, Max; Eriksson, Daniel; Sjödin, Andreas; Sjöström, Michael; Jansson, Stefan; Antti, Henrik; Trygg, Johan

2005-01-01

Background cDNA microarray technology has emerged as a major player in the parallel detection of biomolecules, but still suffers from fundamental technical problems. Identifying and removing unreliable data is crucial to prevent the risk of receiving illusive analysis results. Visual assessment of spot quality is still a common procedure, despite the time-consuming work of manually inspecting spots in the range of hundreds of thousands or more. Results A novel methodology for cDNA microarray spot quality control is outlined. Multivariate discriminant analysis was used to assess spot quality based on existing and novel descriptors. The presented methodology displays high reproducibility and was found superior in identifying unreliable data compared to other evaluated methodologies. Conclusion The proposed methodology for cDNA microarray spot quality control generates non-discrete values of spot quality which can be utilized as weights in subsequent analysis procedures as well as to discard spots of undesired quality using the suggested threshold values. The MASQOT approach provides a consistent assessment of spot quality and can be considered an alternative to the labor-intensive manual quality assessment process. PMID:16223442

Intelligent control of a multi-degree-of freedom reaction compensating platform system using fuzzy logic

NASA Technical Reports Server (NTRS)

Choi, Benjamin B.; Lawrence, Charles; Lin, Yueh-Jaw

1994-01-01

This paper presents the development of a general-purpose fuzzy logic (FL) control methodology for isolating the external vibratory disturbances of space-based devices. According to the desired performance specifications, a full investigation regarding the development of an FL controller was done using different scenarios, such as variances of passive reaction-compensating components and external disturbance load. It was shown that the proposed FL controller is robust in that the FL-controlled system closely follows the prespecified ideal reference model. The comparative study also reveals that the FL-controlled system achieves significant improvement in reducing vibrations over passive systems.

Absence of bacterial DNA in culture-negative urine from cats with and without lower urinary tract disease.

PubMed

Lund, Heidi Sjetne; Skogtun, Gaute; Sørum, Henning; Eggertsdóttir, Anna Vigdís

2015-10-01

A diagnosis of bacterial cystitis commonly relies on a positive microbiological culture demonstrating the presence of a significant number of colony-forming units/ml urine, as urine within the upper urinary tract, bladder and proximal urethra generally is considered sterile. Recent studies from human and veterinary medicine indicate the presence of non-culturable bacteria in culture-negative urine samples. The aim of the present study was to determine the occurrence of bacterial DNA in culture-negative urine samples from cats with signs of feline lower urinary tract disease (FLUTD) and healthy control cats by 16S ribosomal DNA PCR and subsequent sequencing. The study sample included 38 culture-negative urine samples from cats with FLUTD and 43 culture-negative samples from control cats. Eight culture-positive urine samples from cats with FLUTD were included as external positive controls in addition to negative reaction controls. Of possible methodological limitations, degradation of DNA due to storage, the use of non-sedimented urine for DNA isolation and lack of internal positive reaction controls should be mentioned. The positive controls were recognised, but occurrence of bacterial DNA in culture-negative urine from cats with or without signs of lower urinary tract disease was not demonstrated. However, considering the possible methodological limitations, the presence of bacterial DNA in the urine of culture-negative FLUTD cats cannot be excluded based on the present results alone. Therefore, a prospective study reducing the possibility of degradation of DNA due to storage, in combination with modifications enhancing the chance of detecting even lower levels of bacterial DNA in culture-negative samples, seems warranted. © ISFM and AAFP 2014.

Diagnostic ultrasound imaging for lateral epicondylalgia: a case-control study.

PubMed

Heales, Luke James; Broadhurst, Nathan; Mellor, Rebecca; Hodges, Paul William; Vicenzino, Bill

2014-11-01

Lateral epicondylalgia (LE) is clinically diagnosed as pain over the lateral elbow that is provoked by gripping. Usually, LE responds well to conservative intervention; however, those who fail such treatment require further evaluation, including musculoskeletal ultrasound. Previous studies of musculoskeletal ultrasound have methodological flaws, such as lack of assessor blinding and failure to control for participant age, sex, and arm dominance. The purpose of this study was to assess the diagnostic use of blinded ultrasound imaging in people with clinically diagnosed LE compared with that in a control group matched for age, sex, and arm dominance. Participants (30 with LE and 30 controls) underwent clinical examination as the criterion standard test. Unilateral LE was defined as pain over the lateral epicondyle, which was provoked by palpation, resisted wrist and finger extension, and gripping. Controls without symptoms were matched for age, sex, and arm dominance. Ultrasound investigations were performed by two sonographers using a standardized protocol. Grayscale images were assessed for signs of tendon pathology and rated on a four-point ordinal scale. Power Doppler was used to assess neovascularity and rated on a five-point ordinal scale. The combination of grayscale and power Doppler imaging revealed an overall sensitivity of 90% and specificity of 47%. The positive and negative likelihood ratios for combined grayscale and power Doppler imaging were 1.69 and 0.21, respectively. Although ultrasound imaging helps confirm the absence of LE, when findings are negative for tendinopathic changes, the high prevalence of tendinopathic changes in pain-free controls challenges the specificity of the measure. The validity of ultrasound imaging to confirm tendon pathology in clinically diagnosed LE requires further study with strong methodology.

Active Power Control of Wind Turbines for Ancillary Services: A Comparison of Pitch and Torque Control Methodologies

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

Aho, Jacob; Fleming, Paul; Pao, Lucy Y.

As wind energy generation becomes more prevalent in some regions, there is increased demand for wind power plants to provide ancillary services, which are essential for grid reliability. This paper compares two different wind turbine control methodologies to provide active power control (APC) ancillary services, which include derating or curtailing power generation, providing automatic generation control (AGC), and providing primary frequency control (PFC). The torque APC controller provides all power control through the power electronics whereas the pitch APC controller uses the blade pitch actuators as the primary means of power control. These controllers are simulated under various wind conditionsmore » with different derating set points and AGC participation levels. The metrics used to compare their performance are the damage equivalent loads (DELs) induced on the structural components and AGC performance metrics, which are used to determine the payments for AGC services by system operators in the United States. The simulation results show that derating the turbine reduces structural loads for both control methods, with the APC pitch control providing larger reductions in DELs, lower AGC performance scores, and higher root-mean-square pitch rates. Providing AGC increases the structural loads when compared to only derating the turbine, but even the AGC DELs are generally lower than those of the baseline control system. The torque APC control methodology also allows for more sustained PFC responses under certain derating conditions.« less

An Inverse Neural Controller Based on the Applicability Domain of RBF Network Models

PubMed Central

Alexandridis, Alex; Stogiannos, Marios; Papaioannou, Nikolaos; Zois, Elias; Sarimveis, Haralambos

2018-01-01

This paper presents a novel methodology of generic nature for controlling nonlinear systems, using inverse radial basis function neural network models, which may combine diverse data originating from various sources. The algorithm starts by applying the particle swarm optimization-based non-symmetric variant of the fuzzy means (PSO-NSFM) algorithm so that an approximation of the inverse system dynamics is obtained. PSO-NSFM offers models of high accuracy combined with small network structures. Next, the applicability domain concept is suitably tailored and embedded into the proposed control structure in order to ensure that extrapolation is avoided in the controller predictions. Finally, an error correction term, estimating the error produced by the unmodeled dynamics and/or unmeasured external disturbances, is included to the control scheme to increase robustness. The resulting controller guarantees bounded input-bounded state (BIBS) stability for the closed loop system when the open loop system is BIBS stable. The proposed methodology is evaluated on two different control problems, namely, the control of an experimental armature-controlled direct current (DC) motor and the stabilization of a highly nonlinear simulated inverted pendulum. For each one of these problems, appropriate case studies are tested, in which a conventional neural controller employing inverse models and a PID controller are also applied. The results reveal the ability of the proposed control scheme to handle and manipulate diverse data through a data fusion approach and illustrate the superiority of the method in terms of faster and less oscillatory responses. PMID:29361781

Response to a comment on Cullen K "From Squires Quest! II: A serious video game intervention": Methodological issues

USDA-ARS?s Scientific Manuscript database

In response to comments about our article, "Meal-specific dietary changes from Squires Quest! II: a serious video game intervention," we concur that studies on video game interventions are important. A future study with a control group receiving no video game intervention and the collection of poten...

Using Theory of Planned Behavior to Predict Healthy Eating among Danish Adolescents

ERIC Educational Resources Information Center

Gronhoj, Alice; Bech-Larsen, Tino; Chan, Kara; Tsang, Lennon

2013-01-01

Purpose: The purpose of the study was to apply the theory of planned behavior to predict Danish adolescents' behavioral intention for healthy eating. Design/methodology/approach: A cluster sample survey of 410 students aged 11 to 16 years studying in Grade 6 to Grade 10 was conducted in Denmark. Findings: Perceived behavioral control followed by…

The Influences of Static and Interactive Dynamic Facial Stimuli on Visual Strategies in Persons with Asperger Syndrome

ERIC Educational Resources Information Center

Falkmer, Marita; Bjallmark, Anna; Larsson, Matilda; Falkmer, Torbjorn

2011-01-01

Several studies, using eye tracking methodology, suggest that different visual strategies in persons with autism spectrum conditions, compared with controls, are applied when viewing facial stimuli. Most eye tracking studies are, however, made in laboratory settings with either static (photos) or non-interactive dynamic stimuli, such as video…

77 FR 5850 - Notice of Random Assignment Study To Evaluate Workforce Investment Act Adult and Dislocated...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-06

...: One commenter was concerned about 50 percent of the participants being placed in a control group. The... impact methodology for the evaluation. The design of the study was described as follows: The evaluation... eligible for intensive services would be randomly assigned to one of three groups. The three research...