Observational Study Designs for Comparative Effectiveness Research: An Alternative Approach to Close Evidence Gaps in Head-and-Neck Cancer

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

Goulart, Bernardo H.L., E-mail: bhg@uw.edu; University of Washington, Seattle, Washington; Ramsey, Scott D.

Comparative effectiveness research (CER) has emerged as an approach to improve quality of care and patient outcomes while reducing healthcare costs by providing evidence to guide healthcare decisions. Randomized controlled trials (RCTs) have represented the ideal study design to support treatment decisions in head-and-neck (H and N) cancers. In RCTs, formal chance (randomization) determines treatment allocation, which prevents selection bias from distorting the measure of treatment effects. Despite this advantage, only a minority of patients qualify for inclusion in H and N RCTs, which limits the validity of their results to the broader H and N cancer patient population seenmore » in clinical practice. Randomized controlled trials often do not address other knowledge gaps in the management of H and N cancer, including treatment comparisons for rare types of H and N cancers, monitoring of rare or late toxicity events (eg, osteoradionecrosis), or in some instances an RCT is simply not feasible. Observational studies, or studies in which treatment allocation occurs independently of investigators' choice or randomization, may address several of these gaps in knowledge, thereby complementing the role of RCTs. This critical review discusses how observational CER studies complement RCTs in generating the evidence to inform healthcare decisions and improve the quality of care and outcomes of H and N cancer patients. Review topics include a balanced discussion about the strengths and limitations of both RCT and observational CER study designs; a brief description of design and analytic techniques to handle selection bias in observational studies; examples of observational studies that inform current clinical practices and management of H and N cancers; and suggestions for relevant CER questions that could be addressed by an observational study design.« less

Observational study designs for comparative effectiveness research: an alternative approach to close evidence gaps in head-and-neck cancer.

PubMed

Goulart, Bernardo H L; Ramsey, Scott D; Parvathaneni, Upendra

2014-01-01

Comparative effectiveness research (CER) has emerged as an approach to improve quality of care and patient outcomes while reducing healthcare costs by providing evidence to guide healthcare decisions. Randomized controlled trials (RCTs) have represented the ideal study design to support treatment decisions in head-and-neck (H&N) cancers. In RCTs, formal chance (randomization) determines treatment allocation, which prevents selection bias from distorting the measure of treatment effects. Despite this advantage, only a minority of patients qualify for inclusion in H&N RCTs, which limits the validity of their results to the broader H&N cancer patient population seen in clinical practice. Randomized controlled trials often do not address other knowledge gaps in the management of H&N cancer, including treatment comparisons for rare types of H&N cancers, monitoring of rare or late toxicity events (eg, osteoradionecrosis), or in some instances an RCT is simply not feasible. Observational studies, or studies in which treatment allocation occurs independently of investigators' choice or randomization, may address several of these gaps in knowledge, thereby complementing the role of RCTs. This critical review discusses how observational CER studies complement RCTs in generating the evidence to inform healthcare decisions and improve the quality of care and outcomes of H&N cancer patients. Review topics include a balanced discussion about the strengths and limitations of both RCT and observational CER study designs; a brief description of design and analytic techniques to handle selection bias in observational studies; examples of observational studies that inform current clinical practices and management of H&N cancers; and suggestions for relevant CER questions that could be addressed by an observational study design. Copyright © 2014 Elsevier Inc. All rights reserved.

Development and evaluation of a study design typology for human research.

PubMed

Carini, Simona; Pollock, Brad H; Lehmann, Harold P; Bakken, Suzanne; Barbour, Edward M; Gabriel, Davera; Hagler, Herbert K; Harper, Caryn R; Mollah, Shamim A; Nahm, Meredith; Nguyen, Hien H; Scheuermann, Richard H; Sim, Ida

2009-11-14

A systematic classification of study designs would be useful for researchers, systematic reviewers, readers, and research administrators, among others. As part of the Human Studies Database Project, we developed the Study Design Typology to standardize the classification of study designs in human research. We then performed a multiple observer masked evaluation of active research protocols in four institutions according to a standardized protocol. Thirty-five protocols were classified by three reviewers each into one of nine high-level study designs for interventional and observational research (e.g., N-of-1, Parallel Group, Case Crossover). Rater classification agreement was moderately high for the 35 protocols (Fleiss' kappa = 0.442) and higher still for the 23 quantitative studies (Fleiss' kappa = 0.463). We conclude that our typology shows initial promise for reliably distinguishing study design types for quantitative human research.

Observational studies are complementary to randomized controlled trials.

PubMed

Grootendorst, Diana C; Jager, Kitty J; Zoccali, Carmine; Dekker, Friedo W

2010-01-01

Randomized controlled trials (RCTs) are considered the gold standard study design to investigate the effect of health interventions, including treatment. However, in some situations, it may be unnecessary, inappropriate, impossible, or inadequate to perform an RCT. In these special situations, well-designed observational studies, including cohort and case-control studies, may provide an alternative to doing nothing in order to obtain estimates of treatment effect. It should be noted that such studies should be performed with caution and correctly. The aims of this review are (1) to explain why RCTs are considered the optimal study design to evaluate treatment effects, (2) to describe the situations in which an RCT is not possible and observational studies are an adequate alternative, and (3) to explain when randomization is not needed and can be approximated in observational studies. Examples from the nephrology literature are used for illustration. Copyright 2009 S. Karger AG, Basel.

From pattern to process: The strategy of the Earth Observing System: Volume 2: EOS Science Steering Committee report

NASA Technical Reports Server (NTRS)

1987-01-01

The Earth Observing System (EOS) represents a new approach to the study of the Earth. It consists of remotely sensed and correlative in situ observations designed to address important, interrelated global-scale processes. There is an urgent need to study the Earth as a complete, integrated system in order to understand and predict changes caused by human activities and natural processes. The EOS approach is based on an information system concept and designed to provide a long-term study of the Earth using a variety of measurement methods from both operational and research satellite payloads and continuing ground-based Earth science studies. The EOS concept builds on the foundation of the earlier, single-discipline space missions designed for relatively short observation periods. Continued progress in our understanding of the Earth as a system will come from EOS observations spanning several decades using a variety of contemporaneous measurements.

An Observational Study for Evaluating the Effects of Interpersonal Problem-Solving Skills Training on Behavioural Dimensions

ERIC Educational Resources Information Center

Anliak, Sakire; Sahin, Derya

2010-01-01

The present observational study was designed to evaluate the effectiveness of the I Can Problem Solve (ICPS) programme on behavioural change from aggression to pro-social behaviours by using the DECB rating scale. Non-participant observation method was used to collect data in pretest-training-posttest design. It was hypothesised that the ICPS…

Observational studies and the difficult quest for causality: lessons from vaccine effectiveness and impact studies.

PubMed

Lipsitch, Marc; Jha, Ayan; Simonsen, Lone

2016-12-01

Although randomized placebo-controlled trials (RCT) are critical to establish efficacy of vaccines at the time of licensure, important remaining questions about vaccine effectiveness (VE)-used here to include individual-level measures and population-wide impact of vaccine programmes-can only be answered once the vaccine is in use, from observational studies. However, such studies are inherently at risk for bias. Using a causal framework and illustrating with examples, we review newer approaches to detecting and avoiding confounding and selection bias in three major classes of observational study design: cohort, case-control and ecological studies. Studies of influenza VE, especially in seniors, are an excellent demonstration of the challenges of detecting and reducing such bias, and so we use influenza VE as a running example. We take a fresh look at the time-trend studies often dismissed as 'ecological'. Such designs are the only observational study design that can measure the overall effect of a vaccination programme [indirect (herd) as well as direct effects], and are in fact already an important part of the evidence base for several vaccines currently in use. Despite the great strides towards more robust observational study designs, challenges lie ahead for evaluating best practices for achieving robust unbiased results from observational studies. This is critical for evaluation of national and global vaccine programme effectiveness. © The Author 2016; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

A Study of Vehicle Structural Layouts in Post-WWII Aircraft

NASA Technical Reports Server (NTRS)

Sensmeier, Mark D.; Samareh, Jamshid A.

2004-01-01

In this paper, results of a study of structural layouts of post-WWII aircraft are presented. This study was undertaken to provide the background information necessary to determine typical layouts, design practices, and industry trends in aircraft structural design. Design decisions are often predicated not on performance-related criteria, but rather on such factors as manufacturability, maintenance access, and of course cost. For this reason, a thorough understanding of current best practices in the industry is required as an input for the design optimization process. To determine these best practices and industry trends, a large number of aircraft structural cutaway illustrations were analyzed for five different aircraft categories (commercial transport jets, business jets, combat jet aircraft, single engine propeller aircraft, and twin-engine propeller aircraft). Several aspects of wing design and fuselage design characteristics are presented here for the commercial transport and combat aircraft categories. A great deal of commonality was observed for transport structure designs over a range of eras and manufacturers. A much higher degree of variability in structural designs was observed for the combat aircraft, though some discernable trends were observed as well.

Research designs and making causal inferences from health care studies.

PubMed

Flannelly, Kevin J; Jankowski, Katherine R B

2014-01-01

This article summarizes the major types of research designs used in healthcare research, including experimental, quasi-experimental, and observational studies. Observational studies are divided into survey studies (descriptive and correlational studies), case-studies and analytic studies, the last of which are commonly used in epidemiology: case-control, retrospective cohort, and prospective cohort studies. Similarities and differences among the research designs are described and the relative strength of evidence they provide is discussed. Emphasis is placed on five criteria for drawing causal inferences that are derived from the writings of the philosopher John Stuart Mill, especially his methods or canons. The application of the criteria to experimentation is explained. Particular attention is given to the degree to which different designs meet the five criteria for making causal inferences. Examples of specific studies that have used various designs in chaplaincy research are provided.

Variation in choice of study design: findings from the Epidemiology Design Decision Inventory and Evaluation (EDDIE) survey.

PubMed

Stang, Paul E; Ryan, Patrick B; Overhage, J Marc; Schuemie, Martijn J; Hartzema, Abraham G; Welebob, Emily

2013-10-01

Researchers using observational data to understand drug effects must make a number of analytic design choices that suit the characteristics of the data and the subject of the study. Review of the published literature suggests that there is a lack of consistency even when addressing the same research question in the same database. To characterize the degree of similarity or difference in the method and analysis choices made by observational database research experts when presented with research study scenarios. On-line survey using research scenarios on drug-effect studies to capture method selection and analysis choices that follow a dependency branching based on response to key questions. Voluntary participants experienced in epidemiological study design solicited for participation through registration on the Observational Medical Outcomes Partnership website, membership in particular professional organizations, or links in relevant newsletters. Description (proportion) of respondents selecting particular methods and making specific analysis choices based on individual drug-outcome scenario pairs. The number of questions/decisions differed based on stem questions of study design, time-at-risk, outcome definition, and comparator. There is little consistency across scenarios, by drug or by outcome of interest, in the decisions made for design and analyses in scenarios using large healthcare databases. The most consistent choice was the cohort study design but variability in the other critical decisions was common. There is great variation among epidemiologists in the design and analytical choices that they make when implementing analyses in observational healthcare databases. These findings confirm that it will be important to generate empiric evidence to inform these decisions and to promote a better understanding of the impact of standardization on research implementation.

A Numerical Climate Observing Network Design Study

NASA Technical Reports Server (NTRS)

Stammer, Detlef

2003-01-01

This project was concerned with three related questions of an optimal design of a climate observing system: 1. The spatial sampling characteristics required from an ARGO system. 2. The degree to which surface observations from ARGO can be used to calibrate and test satellite remote sensing observations of sea surface salinity (SSS) as it is anticipated now. 3. The more general design of an climate observing system as it is required in the near future for CLIVAR in the Atlantic. An important question in implementing an observing system is that of the sampling density required to observe climate-related variations in the ocean. For that purpose this project was concerned with the sampling requirements for the ARGO float system, but investigated also other elements of a climate observing system. As part of this project we studied the horizontal and vertical sampling characteristics of a global ARGO system which is required to make it fully complementary to altimeter data with the goal to capture climate related variations on large spatial scales (less thanAttachment: 1000 km). We addressed this question in the framework of a numerical model study in the North Atlantic with an 1/6 horizontal resolution. The advantage of a numerical design study is the knowledge of the full model state. Sampled by a synthetic float array, model results will therefore allow to test and improve existing deployment strategies with the goal to make the system as optimal and cost-efficient as possible. Attachment: "Optimal observations for variational data assimilation".

Observed Score Linear Equating with Covariates

ERIC Educational Resources Information Center

Branberg, Kenny; Wiberg, Marie

2011-01-01

This paper examined observed score linear equating in two different data collection designs, the equivalent groups design and the nonequivalent groups design, when information from covariates (i.e., background variables correlated with the test scores) was included. The main purpose of the study was to examine the effect (i.e., bias, variance, and…

Magic Mirror, on the Wall-Which Is the Right Study Design of Them All?-Part I.

PubMed

Vetter, Thomas R

2017-06-01

The assessment of a new or existing treatment or intervention typically answers 1 of 3 research-related questions: (1) "Can it work?" (efficacy); (2) "Does it work?" (effectiveness); and (3) "Is it worth it?" (efficiency or cost-effectiveness). There are a number of study designs that on a situational basis are appropriate to apply in conducting research. These study designs are classified as experimental, quasi-experimental, or observational, with observational studies being further divided into descriptive and analytic categories. This first of a 2-part statistical tutorial reviews these 3 salient research questions and describes a subset of the most common types of experimental and quasi-experimental study design. Attention is focused on the strengths and weaknesses of each study design to assist in choosing which is appropriate for a given study objective and hypothesis as well as the particular study setting and available resources and data. Specific studies and papers are highlighted as examples of a well-chosen, clearly stated, and properly executed study design type.

Comparative effectiveness research in cancer with observational data.

PubMed

Giordano, Sharon H

2015-01-01

Observational studies are increasingly being used for comparative effectiveness research. These studies can have the greatest impact when randomized trials are not feasible or when randomized studies have not included the population or outcomes of interest. However, careful attention must be paid to study design to minimize the likelihood of selection biases. Analytic techniques, such as multivariable regression modeling, propensity score analysis, and instrumental variable analysis, also can also be used to help address confounding. Oncology has many existing large and clinically rich observational databases that can be used for comparative effectiveness research. With careful study design, observational studies can produce valid results to assess the benefits and harms of a treatment or intervention in representative real-world populations.

Research Design Options for Intervention Studies.

PubMed

Lobo, Michele A; Kagan, Sarah H; Corrigan, John D

2017-07-01

To review research designs for rehabilitation. Single-case, observational, and qualitative designs are highlighted in terms of recent advances and ability to answer important scientific questions about rehabilitation. Single-case, observational, and qualitative designs can be conducted in a systematic and rigorous manner that provides important information that cannot be acquired using more common designs, such as randomized controlled trials. These less commonly used designs may be more feasible and effective in answering many research questions in the field of rehabilitation. Researchers should consider these designs when selecting the optimal design to answer their research questions. We should improve education about the advantages and disadvantages of existing research designs to enable more critical analysis of the scientific literature we read and review to avoid undervaluing studies not within more commonly used categories.

From randomized controlled trials to observational studies.

PubMed

Silverman, Stuart L

2009-02-01

Randomized controlled trials are considered the gold standard in the hierarchy of research designs for evaluating the efficacy and safety of a treatment intervention. However, their results can have limited applicability to patients in clinical settings. Observational studies using large health care databases can complement findings from randomized controlled trials by assessing treatment effectiveness in patients encountered in day-to-day clinical practice. Results from these designs can expand upon outcomes of randomized controlled trials because of the use of larger and more diverse patient populations with common comorbidities and longer follow-up periods. Furthermore, well-designed observational studies can identify clinically important differences among therapeutic options and provide data on long-term drug effectiveness and safety.

Overview of clinical research design.

PubMed

Hartung, Daniel M; Touchette, Daniel

2009-02-15

Basic concepts and terminology of clinical research design are presented for new clinical investigators. Clinical research, research involving human subjects, can be described as either observational or experimental. The findings of all clinical research can be threatened by issues of bias and confounding. Biases are systematic errors in how study subjects are selected or measured, which result in false inferences. Confounding is a distortion in findings that is attributable to mixing variable effects. Uncontrolled observation research is generally more prone to bias and confounding than experimental research. Observational research includes designs such as the cohort study, case-control study, and cross-sectional study, while experimental research typically involves a randomized controlled trial (RCT). The cohort study, which includes the RCT, defines subject allocation on the basis of exposure interest (e.g., drug, disease-management program) and follows the patients to assess the outcomes. The case-control study uses the primary outcome of interest (e.g., adverse event) to define subject allocation, and different exposures are assessed in a retrospective manner. Cross-sectional research evaluates both exposure and outcome concurrently. Each of these design methods possesses different strengths and weaknesses in answering research questions, as well as underlying many study subtypes. While experimental research is the strongest method for establishing causality, it can be difficult to accomplish under many scenarios. Observational clinical research offers many design alternatives that may be appropriate if planned and executed carefully.

Recent progresses in outcome-dependent sampling with failure time data.

PubMed

Ding, Jieli; Lu, Tsui-Shan; Cai, Jianwen; Zhou, Haibo

2017-01-01

An outcome-dependent sampling (ODS) design is a retrospective sampling scheme where one observes the primary exposure variables with a probability that depends on the observed value of the outcome variable. When the outcome of interest is failure time, the observed data are often censored. By allowing the selection of the supplemental samples depends on whether the event of interest happens or not and oversampling subjects from the most informative regions, ODS design for the time-to-event data can reduce the cost of the study and improve the efficiency. We review recent progresses and advances in research on ODS designs with failure time data. This includes researches on ODS related designs like case-cohort design, generalized case-cohort design, stratified case-cohort design, general failure-time ODS design, length-biased sampling design and interval sampling design.

Recent progresses in outcome-dependent sampling with failure time data

PubMed Central

Ding, Jieli; Lu, Tsui-Shan; Cai, Jianwen; Zhou, Haibo

2016-01-01

An outcome-dependent sampling (ODS) design is a retrospective sampling scheme where one observes the primary exposure variables with a probability that depends on the observed value of the outcome variable. When the outcome of interest is failure time, the observed data are often censored. By allowing the selection of the supplemental samples depends on whether the event of interest happens or not and oversampling subjects from the most informative regions, ODS design for the time-to-event data can reduce the cost of the study and improve the efficiency. We review recent progresses and advances in research on ODS designs with failure time data. This includes researches on ODS related designs like case–cohort design, generalized case–cohort design, stratified case–cohort design, general failure-time ODS design, length-biased sampling design and interval sampling design. PMID:26759313

[Realization of design regarding experimental research in the clinical real-world research].

PubMed

He, Q; Shi, J P

2018-04-10

Real world study (RWS), a further verification and supplement for explanatory randomized controlled trial to evaluate the effectiveness of intervention measures in real clinical environment, has increasingly become the focus in the field of research on medical and health care services. However, some people mistakenly equate real world study with observational research, and argue that intervention and randomization cannot be carried out in real world study. In fact, both observational and experimental design are the basic designs in real world study, while the latter usually refers to pragmatic randomized controlled trial and registry-based randomized controlled trial. Other nonrandomized controlled and adaptive designs can also be adopted in the RWS.

Thinking outside the ROCs: Designing decorrelated taggers (DDT) for jet substructure

DOE PAGES

Dolen, James; Harris, Philip; Marzani, Simone; ...

2016-05-26

Here, we explore the scale-dependence and correlations of jet substructure observables to improve upon existing techniques in the identification of highly Lorentz-boosted objects. Modified observables are designed to remove correlations from existing theoretically well-understood observables, providing practical advantages for experimental measurements and searches for new phenomena. We study such observables in W jet tagging and provide recommendations for observables based on considerations beyond signal and background efficiencies.

Observational methods in comparative effectiveness research.

PubMed

Concato, John; Lawler, Elizabeth V; Lew, Robert A; Gaziano, J Michael; Aslan, Mihaela; Huang, Grant D

2010-12-01

Comparative effectiveness research (CER) may be defined informally as an assessment of available options for treating specific medical conditions in selected groups of patients. In this context, the most prominent features of CER are the various patient populations, medical ailments, and treatment options involved in any particular project. Yet, each research investigation also has a corresponding study design or "architecture," and in patient-oriented research a common distinction used to describe such designs are randomized controlled trials (RCTs) versus observational studies. The purposes of this overview, with regard to CER, are to (1) understand how observational studies can provide accurate results, comparable to RCTs; (2) recognize strategies used in selected newer methods for conducting observational studies; (3) review selected observational studies from the Veterans Health Administration; and (4) appreciate the importance of fundamental methodological principles when conducting or evaluating individual studies. Published by Elsevier Inc.

Balancing the Evidence: How to Reconcile the Results of Observational Studies vs. Randomized Clinical Trials in Dialysis.

PubMed

Shen, Jenny I; Lum, Erik L; Chang, Tara I

2016-09-01

Because large randomized clinical trials (RCTs) in dialysis have been relatively scarce, evidence-based dialysis care has depended heavily on the results of observational studies. However, when results from RCTs appear to contradict the findings of observational studies, nephrologists are left to wonder which type of study they should believe. In this editorial, we explore the key differences between observational studies and RCTs in the context of such seemingly conflicting studies in dialysis. Confounding is the major limitation of observational studies, whereas low statistical power and problems with external validity are more likely to limit the findings of RCTs. Differences in the specification of the population, exposure, and outcomes can also contribute to different results among RCTs and observational studies. Rigorous methods are required regardless of what type of study is conducted, and readers should not automatically assume that one type of study design is superior to the other. Ultimately, dialysis care requires both well-designed, well-conducted observational studies and RCTs to move the field forward. © 2016 Wiley Periodicals, Inc.

Balancing the Evidence: How to Reconcile the Results of Observational Studies vs. Randomized Clinical Trials in Dialysis

PubMed Central

Shen, Jenny I.; Lum, Erik L.; Chang, Tara I.

2016-01-01

Because large randomized clinical trials (RCTs) in dialysis have been relatively scarce, evidence-based dialysis care has depended heavily on the results of observational studies. However, when results from RCTs appear to contradict the findings of observational studies, nephrologists are left to wonder which type of study they should believe. In this editorial we explore the key differences between observational studies and RCTs in the context of such seemingly conflicting studies in dialysis. Confounding is the major limitation of observational studies, while low statistical power and problems with external validity are more likely to limit the findings of RCTs. Differences in the specification of the population, exposure, and outcomes can also contribute to different results among RCTs and observational studies. Rigorous methods are required regardless of what type of study is conducted, and readers should not automatically assume that one type of study design is superior to the other. Ultimately, dialysis care requires both well-designed, well-conducted observational studies and RCTs to move the field forward. PMID:27207819

Evaluating the Impact of Database Heterogeneity on Observational Study Results

PubMed Central

Madigan, David; Ryan, Patrick B.; Schuemie, Martijn; Stang, Paul E.; Overhage, J. Marc; Hartzema, Abraham G.; Suchard, Marc A.; DuMouchel, William; Berlin, Jesse A.

2013-01-01

Clinical studies that use observational databases to evaluate the effects of medical products have become commonplace. Such studies begin by selecting a particular database, a decision that published papers invariably report but do not discuss. Studies of the same issue in different databases, however, can and do generate different results, sometimes with strikingly different clinical implications. In this paper, we systematically study heterogeneity among databases, holding other study methods constant, by exploring relative risk estimates for 53 drug-outcome pairs and 2 widely used study designs (cohort studies and self-controlled case series) across 10 observational databases. When holding the study design constant, our analysis shows that estimated relative risks range from a statistically significant decreased risk to a statistically significant increased risk in 11 of 53 (21%) of drug-outcome pairs that use a cohort design and 19 of 53 (36%) of drug-outcome pairs that use a self-controlled case series design. This exceeds the proportion of pairs that were consistent across databases in both direction and statistical significance, which was 9 of 53 (17%) for cohort studies and 5 of 53 (9%) for self-controlled case series. Our findings show that clinical studies that use observational databases can be sensitive to the choice of database. More attention is needed to consider how the choice of data source may be affecting results. PMID:23648805

Initial Validation of the Prekindergarten Classroom Observation Tool and Goal Setting System for Data-Based Coaching

ERIC Educational Resources Information Center

Crawford, April D.; Zucker, Tricia A.; Williams, Jeffrey M.; Bhavsar, Vibhuti; Landry, Susan H.

2013-01-01

Although coaching is a popular approach for enhancing the quality of Tier 1 instruction, limited research has addressed observational measures specifically designed to focus coaching on evidence-based practices. This study explains the development of the prekindergarten (pre-k) Classroom Observation Tool (COT) designed for use in a data-based…

Case-Cohort Studies: Design and Applicability to Hand Surgery.

PubMed

Vojvodic, Miliana; Shafarenko, Mark; McCabe, Steven J

2018-04-24

Observational studies are common research strategies in hand surgery. The case-cohort design offers an efficient and resource-friendly method for risk assessment and outcomes analysis. Case-cohorts remain underrepresented in upper extremity research despite several practical and economic advantages over case-control studies. This report outlines the purpose, utility, and structure of the case-cohort design and offers a sample research question to demonstrate its value to risk estimation for adverse surgical outcomes. The application of well-designed case-cohort studies is advocated in an effort to improve the quality and quantity of observational research evidence in hand and upper extremity surgery. Copyright © 2018 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Observer Use of Standardized Observation Protocols in Consequential Observation Systems

ERIC Educational Resources Information Center

Bell, Courtney A.; Yi, Qi; Jones, Nathan D.; Lewis, Jennifer M.; McLeod, Monica; Liu, Shuangshuang

2014-01-01

Evidence from a handful of large-scale studies suggests that although observers can be trained to score reliably using observation protocols, there are concerns related to initial training and calibration activities designed to keep observers scoring accurately over time (e.g., Bell, et al, 2012; BMGF, 2012). Studies offer little insight into how…

The Reality of Well-Being-Focused Design in Dementia Care: A Case Study of Acute Dementia Wards in the United Kingdom.

PubMed

Catt, Megan; Giridharan, Renganathan

2018-01-01

The study explored design for well-being within dementia care by investigating the adoption of well-being-focused design in real-world practice, through observing National Health Service (NHS) wards. Design for well-being is an approach that considers the psychological and physiological effects of architecture to improve health and well-being. The high psychological care requirement for dementia patients makes them a significant group to study in the evaluation of current hospital facilities. A literature review was conducted to frame the current theoretical perception of the key characteristics of a good environment for dementia care. A framework was generated to summarize and used as an assessment tool in a series of observational visits to NHS wards. Interviews with clinical staff focused on care outcomes and practicalities of implementing well-being-focused design, considering the historical and economical context. Key findings from the observations and interviews were analyzed for recurring themes. The ward observations and interviews provided insight into the current progression of well-being-led design in NHS hospitals in England. The research highlights key areas of success and factors that inhibit further progression. The case studies showed a good degree of ambition to utilize well-being-focused design, with belief among staff that the physical environment has a substantial role in the health and well-being of patients. Staff also felt that this approach is most effective for those in the less advanced stages of dementia. Despite the high level of support, the current degree of implementation appears to be varied.

Observation chart design features affect the detection of patient deterioration: a systematic experimental evaluation.

PubMed

Christofidis, Melany J; Hill, Andrew; Horswill, Mark S; Watson, Marcus O

2016-01-01

To systematically evaluate the impact of several design features on chart-users' detection of patient deterioration on observation charts with early-warning scoring-systems. Research has shown that observation chart design affects the speed and accuracy with which abnormal observations are detected. However, little is known about the contribution of individual design features to these effects. A 2 × 2 × 2 × 2 mixed factorial design, with data-recording format (drawn dots vs. written numbers), scoring-system integration (integrated colour-based system vs. non-integrated tabular system) and scoring-row placement (grouped vs. separate) varied within-participants and scores (present vs. absent) varied between-participants by random assignment. 205 novice chart-users, tested between March 2011-March 2014, completed 64 trials where they saw real patient data presented on an observation chart. Each participant saw eight cases (four containing abnormal observations) on each of eight designs (which represented a factorial combination of the within-participants variables). On each trial, they assessed whether any of the observations were physiologically abnormal, or whether all observations were normal. Response times and error rates were recorded for each design. Participants responded faster (scores present and absent) and made fewer errors (scores absent) using drawn-dot (vs. written-number) observations and an integrated colour-based (vs. non-integrated tabular) scoring-system. Participants responded faster using grouped (vs. separate) scoring-rows when scores were absent, but separate scoring-rows when scores were present. Our findings suggest that several individual design features can affect novice chart-users' ability to detect patient deterioration. More broadly, the study further demonstrates the need to evaluate chart designs empirically. © 2015 John Wiley & Sons Ltd.

Invited Commentary: Beware the Test-Negative Design.

PubMed

Westreich, Daniel; Hudgens, Michael G

2016-09-01

In this issue of the Journal, Sullivan et al. (Am J Epidemiol. 2016;184(5):345-353) carefully examine the theoretical justification for use of the test-negative design, a common observational study design, in assessing the effectiveness of influenza vaccination. Using modern causal inference methods (in particular, directed acyclic graphs), they describe different threats to the validity of inferences drawn about the effect of vaccination from test-negative design studies. These threats include confounding, selection bias, and measurement error in either the exposure or the outcome. While confounding and measurement error are common in observational studies, the potential for selection bias inherent in the test-negative design brings into question the validity of inferences drawn from such studies. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

The Role of Re-Appropriation in Open Design: A Case Study on How Openness in Higher Education for Industrial Design Engineering Can Trigger Global Discussions on the Theme of Urban Gardening

ERIC Educational Resources Information Center

Ostuzzi, Francesca; Conradie, Peter; De Couvreur, Lieven; Detand, Jan; Saldien, Jelle

2016-01-01

This case study explores the opportunities for students of Industrial Design Engineering to engage with direct and indirect stakeholders by making their design process and results into open-ended designed solutions. The reported case study involved 47 students during a two-weeks intensive course on the topic of urban gardening. Observations were…

Prevalence of Recommendations Made Within Dental Research Articles Using Uncontrolled Intervention or Observational Study Designs.

PubMed

Wilson, M K; Chestnutt, I G

2016-03-01

Evidence to inform clinical practice is reliant on research carried out using appropriate study design. The objectives of this work were to (i) identify the prevalence of articles reporting on human studies using uncontrolled intervention or observational research designs published in peer-reviewed dental journals and (ii) determine the nature of recommendations made by these articles. Six peer-reviewed dental journals were selected. Issues published in January to June 2013 were examined and the types of articles published categorized. Following pre-defined inclusion/exclusion criteria, human studies classified as using uncontrolled intervention or observational research designs were subject to detailed review by two independent investigators, to examine if they presented clinical, policy or research recommendations and if these recommendations were supported by the data presented. 52.9% (n = 156) of studies published during the time period met the inclusion criteria. Studies with uncontrolled intervention or observational research designs comprised a larger proportion of the primary research studies published in the journals with lower impact factors (73.3%; n = 107) compared to the high impact journals (38.9%; n = 49). Analysis showed that 60.9% (n = 95) of the included studies made recommendations for clinical practice/dental policy. In 28.2% (n = 44) of studies, the clinical/policy recommendations made were judged to not be fully supported by the data presented. Many studies published in the current dental literature, which are not considered to produce strong evidence, make recommendations for clinical practice or policy. There were some cases when the recommendations were not fully supported by the data presented. Copyright © 2016 Elsevier Inc. All rights reserved.

Family learning with mobile devices in the outdoors: Designing an e-Trailguide to facilitate families' joint engagement with the natural world

NASA Astrophysics Data System (ADS)

McClain, Lucy R.

This study describes the implementation of a self-guiding mobile learning tool designed to support families' engagements with the natural world as they explored the flora and fauna along one nature trail at an environmental center. Thirty-one family groups (n = 105 individuals) participated in this study during the summer season and used an iPad-based e-Trailguide during their nature walk. Design-based research methods guided this study's design, which focused on the third iteration of the e-Trailguide. Data included evaluation of families' content knowledge gains related to the local biodiversity as revealed through post-hike interviews, while videorecords of each family's nature walk experience were also collected. Qualitative analyses focused on the design features within the e-Trailguide that supported the families' technology-mediated engagements with nature and their interactions with each other at one Discovery Spot along the nature trail. Findings include: (a) open-ended interviews after the e-Trailguide experience provided a descriptive understanding of the families' conceptual knowledge gains; (b) four place-based design features within the e-Trailguide enabled and supported families' observational, pointing, and tactile investigation engagements with the natural world; (c) parents took on teacher-like roles for their children by connecting information from the e-Trailguide to the natural objects nearby as evidenced through their frequency of pointing gestures; and (d) the development of an analytical framework related to joint observation strategies used between family members to support science-related sense making. Design recommendations for the future implementation of e-Trailguides in outdoor settings include the incorporation of place-based observational questions, place-based textual prompts for focusing observations, drawing activities to record observations, and place-based images to support identification of wildlife. Key words: family learning, engagement, mobile-based learning, outdoor learning, observation, environmental education, informal science learning.

Urban Environment Development based on Universal Design Principles

NASA Astrophysics Data System (ADS)

Harsritanto, Bangun Ir

2018-02-01

Universal Design is a design which facilitated full range of human diversity. By applying Universal design principles, urban environment can be more functional and more user-friendly for everyone. This study examined five urban streets of South Korea as a country experienced on developing various urban street designs based on universal design. This study aimed to examine and compare the South Korea cases using seven principles of universal design. The research methods of this study are literature study, case study, and site observation. The results of this study are: South Korea cases are good practices, urgency of implementing the direction into local regulations; and change of urban development paradigm.

STRengthening Analytical Thinking for Observational Studies: the STRATOS initiative

PubMed Central

Sauerbrei, Willi; Abrahamowicz, Michal; Altman, Douglas G; le Cessie, Saskia; Carpenter, James

2014-01-01

The validity and practical utility of observational medical research depends critically on good study design, excellent data quality, appropriate statistical methods and accurate interpretation of results. Statistical methodology has seen substantial development in recent times. Unfortunately, many of these methodological developments are ignored in practice. Consequently, design and analysis of observational studies often exhibit serious weaknesses. The lack of guidance on vital practical issues discourages many applied researchers from using more sophisticated and possibly more appropriate methods when analyzing observational studies. Furthermore, many analyses are conducted by researchers with a relatively weak statistical background and limited experience in using statistical methodology and software. Consequently, even ‘standard’ analyses reported in the medical literature are often flawed, casting doubt on their results and conclusions. An efficient way to help researchers to keep up with recent methodological developments is to develop guidance documents that are spread to the research community at large. These observations led to the initiation of the strengthening analytical thinking for observational studies (STRATOS) initiative, a large collaboration of experts in many different areas of biostatistical research. The objective of STRATOS is to provide accessible and accurate guidance in the design and analysis of observational studies. The guidance is intended for applied statisticians and other data analysts with varying levels of statistical education, experience and interests. In this article, we introduce the STRATOS initiative and its main aims, present the need for guidance documents and outline the planned approach and progress so far. We encourage other biostatisticians to become involved. PMID:25074480

Impact of Instructional Design on Virtual Teamwork

ERIC Educational Resources Information Center

Rawlings, Melody

2012-01-01

The purpose of this participatory action research study was to answer the following research question: How does online instructional design impact students' virtual teamwork performance? Through the lens of social constructivism, a qualitative, in-depth multi-case study design was utilized to conduct document analyses, observations, and student…

Randomized clinical trials and observational studies in the assessment of drug safety.

PubMed

Sawchik, J; Hamdani, J; Vanhaeverbeek, M

2018-05-01

Randomized clinical trials are considered as the preferred design to assess the potential causal relationships between drugs or other medical interventions and intended effects. For this reason, randomized clinical trials are generally the basis of development programs in the life cycle of drugs and the cornerstone of evidence-based medicine. Instead, randomized clinical trials are not the design of choice for the detection and assessment of rare, delayed and/or unexpected effects related to drug safety. Moreover, the highly homogeneous populations resulting from restrictive eligibility criteria make randomized clinical trials inappropriate to describe comprehensively the safety profile of drugs. In that context, observational studies have a key added value when evaluating the benefit-risk balance of the drugs. However, observational studies are more prone to bias than randomized clinical trials and they have to be designed, conducted and reported judiciously. In this article, we discuss the strengths and limitations of randomized clinical trials and of observational studies, more particularly regarding their contribution to the knowledge of medicines' safety profile. In addition, we present general recommendations for the sensible use of observational data. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Metformin and the Risk of Cancer

PubMed Central

Suissa, Samy; Azoulay, Laurent

2012-01-01

OBJECTIVE Time-related biases in observational studies of drug effects have been described extensively in different therapeutic areas but less so in diabetes. Immortal time bias, time-window bias, and time-lag bias all tend to greatly exaggerate the benefits observed with a drug. RESEARCH DESIGN AND METHODS These time-related biases are described and shown to be prominent in observational studies that have associated metformin with impressive reductions in the incidence of and mortality from cancer. As a consequence, metformin received much attention as a potential anticancer agent; these observational studies sparked the conduction of randomized, controlled trials of metformin as cancer treatment. However, the spectacular effects reported in these studies are compatible with time-related biases. RESULTS We found that 13 observational studies suffered from immortal time bias; 9 studies had not considered time-window bias, whereas other studies did not consider inherent time-lagging issues when comparing the first-line treatment metformin with second- or third-line treatments. These studies, subject to time-related biases that are avoidable with proper study design and data analysis, led to illusory extraordinarily significant effects, with reductions in cancer risk with metformin ranging from 20 to 94%. Three studies that avoided these biases reported no effect of metformin use on cancer incidence. CONCLUSIONS Although observational studies are important to better understand the effects of drugs, their proper design and analysis is essential to avoid major time-related biases. With respect to metformin, the scientific evidence of its potential beneficial effects on cancer would need to be reassessed critically before embarking on further long and expensive trials. PMID:23173135

An Empirical Study on Students' Ability to Comprehend Design Patterns

ERIC Educational Resources Information Center

Chatzigeorgiou, Alexander; Tsantalis, Nikolaos; Deligiannis, Ignatios

2008-01-01

Design patterns have become a widely acknowledged software engineering practice and therefore have been incorporated in the curricula of most computer science departments. This paper presents an observational study on students' ability to understand and apply design patterns. Within the context of a postgraduate software engineering course,…

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.

On-Line Critiques in Collaborative Design Studio

ERIC Educational Resources Information Center

Sagun, Aysu; Demirkan, Halime

2009-01-01

In this study, the Design Collaboration Model (DCM) was developed to provide a medium for the on-line collaboration of the design courses. The model was based on the situated and reflective practice characteristics of the design process. The segmentation method was used to analyse the design process observed both in the design diaries and the…

Observations Regarding Use of Advanced CFD Analysis, Sensitivity Analysis, and Design Codes in MDO

NASA Technical Reports Server (NTRS)

Newman, Perry A.; Hou, Gene J. W.; Taylor, Arthur C., III

1996-01-01

Observations regarding the use of advanced computational fluid dynamics (CFD) analysis, sensitivity analysis (SA), and design codes in gradient-based multidisciplinary design optimization (MDO) reflect our perception of the interactions required of CFD and our experience in recent aerodynamic design optimization studies using CFD. Sample results from these latter studies are summarized for conventional optimization (analysis - SA codes) and simultaneous analysis and design optimization (design code) using both Euler and Navier-Stokes flow approximations. The amount of computational resources required for aerodynamic design using CFD via analysis - SA codes is greater than that required for design codes. Thus, an MDO formulation that utilizes the more efficient design codes where possible is desired. However, in the aerovehicle MDO problem, the various disciplines that are involved have different design points in the flight envelope; therefore, CFD analysis - SA codes are required at the aerodynamic 'off design' points. The suggested MDO formulation is a hybrid multilevel optimization procedure that consists of both multipoint CFD analysis - SA codes and multipoint CFD design codes that perform suboptimizations.

Development of a Design-Based Learning Curriculum through Design-Based Research for a Technology-Enabled Science Classroom

ERIC Educational Resources Information Center

Kim, Paul; Suh, Esther; Song, Donggil

2015-01-01

This exploratory study provides a deeper look into the aspects of students' experience from design-based learning (DBL) activities for fifth grade students. Using design-based research (DBR), this study was conducted on a series of science learning activities leveraging mobile phones with relevant applications and sensors. We observed 3 different…

Evaluation of a rule-based method for epidemiological document classification towards the automation of systematic reviews.

PubMed

Karystianis, George; Thayer, Kristina; Wolfe, Mary; Tsafnat, Guy

2017-06-01

Most data extraction efforts in epidemiology are focused on obtaining targeted information from clinical trials. In contrast, limited research has been conducted on the identification of information from observational studies, a major source for human evidence in many fields, including environmental health. The recognition of key epidemiological information (e.g., exposures) through text mining techniques can assist in the automation of systematic reviews and other evidence summaries. We designed and applied a knowledge-driven, rule-based approach to identify targeted information (study design, participant population, exposure, outcome, confounding factors, and the country where the study was conducted) from abstracts of epidemiological studies included in several systematic reviews of environmental health exposures. The rules were based on common syntactical patterns observed in text and are thus not specific to any systematic review. To validate the general applicability of our approach, we compared the data extracted using our approach versus hand curation for 35 epidemiological study abstracts manually selected for inclusion in two systematic reviews. The returned F-score, precision, and recall ranged from 70% to 98%, 81% to 100%, and 54% to 97%, respectively. The highest precision was observed for exposure, outcome and population (100%) while recall was best for exposure and study design with 97% and 89%, respectively. The lowest recall was observed for the population (54%), which also had the lowest F-score (70%). The generated performance of our text-mining approach demonstrated encouraging results for the identification of targeted information from observational epidemiological study abstracts related to environmental exposures. We have demonstrated that rules based on generic syntactic patterns in one corpus can be applied to other observational study design by simple interchanging the dictionaries aiming to identify certain characteristics (i.e., outcomes, exposures). At the document level, the recognised information can assist in the selection and categorization of studies included in a systematic review. Copyright © 2017 Elsevier Inc. All rights reserved.

Facilitating Real-Time Observation of, and Peer Discussion and Feedback about, Practice in Writing Classrooms

ERIC Educational Resources Information Center

Parr, Judy M.; Hawe, Eleanor

2017-01-01

This study investigates conditions designed to optimize learning where professionals utilize the expertise and support of one another. It describes a research--practice collaboration to enhance teacher knowledge and practice through peer observation of, and feedback about, classroom practice in writing. A collaboratively designed observation…

A Practical Solution to Optimizing the Reliability of Teaching Observation Measures under Budget Constraints

ERIC Educational Resources Information Center

Meyer, J. Patrick; Liu, Xiang; Mashburn, Andrew J.

2014-01-01

Researchers often use generalizability theory to estimate relative error variance and reliability in teaching observation measures. They also use it to plan future studies and design the best possible measurement procedures. However, designing the best possible measurement procedure comes at a cost, and researchers must stay within their budget…

Concordance of Results from Randomized and Observational Analyses within the Same Study: A Re-Analysis of the Women's Health Initiative Limited-Access Dataset.

PubMed

Bolland, Mark J; Grey, Andrew; Gamble, Greg D; Reid, Ian R

2015-01-01

Observational studies (OS) and randomized controlled trials (RCTs) often report discordant results. In the Women's Health Initiative Calcium and Vitamin D (WHI CaD) RCT, women were randomly assigned to CaD or placebo, but were permitted to use personal calcium and vitamin D supplements, creating a unique opportunity to compare results from randomized and observational analyses within the same study. WHI CaD was a 7-year RCT of 1g calcium/400IU vitamin D daily in 36,282 post-menopausal women. We assessed the effects of CaD on cardiovascular events, death, cancer and fracture in a randomized design- comparing CaD with placebo in 43% of women not using personal calcium or vitamin D supplements- and in a observational design- comparing women in the placebo group (44%) using personal calcium and vitamin D supplements with non-users. Incidence was assessed using Cox proportional hazards models, and results from the two study designs deemed concordant if the absolute difference in hazard ratios was ≤0.15. We also compared results from WHI CaD to those from the WHI Observational Study(WHI OS), which used similar methodology for analyses and recruited from the same population. In WHI CaD, for myocardial infarction and stroke, results of unadjusted and 6/8 covariate-controlled observational analyses (age-adjusted, multivariate-adjusted, propensity-adjusted, propensity-matched) were not concordant with the randomized design results. For death, hip and total fracture, colorectal and total cancer, unadjusted and covariate-controlled observational results were concordant with randomized results. For breast cancer, unadjusted and age-adjusted observational results were concordant with randomized results, but only 1/3 other covariate-controlled observational results were concordant with randomized results. Multivariate-adjusted results from WHI OS were concordant with randomized WHI CaD results for only 4/8 endpoints. Results of randomized analyses in WHI CaD were concordant with observational analyses for 5/8 endpoints in WHI CaD and 4/8 endpoints in WHI OS.

Concordance of Results from Randomized and Observational Analyses within the Same Study: A Re-Analysis of the Women’s Health Initiative Limited-Access Dataset

PubMed Central

Bolland, Mark J.; Grey, Andrew; Gamble, Greg D.; Reid, Ian R.

2015-01-01

Background Observational studies (OS) and randomized controlled trials (RCTs) often report discordant results. In the Women’s Health Initiative Calcium and Vitamin D (WHI CaD) RCT, women were randomly assigned to CaD or placebo, but were permitted to use personal calcium and vitamin D supplements, creating a unique opportunity to compare results from randomized and observational analyses within the same study. Methods WHI CaD was a 7-year RCT of 1g calcium/400IU vitamin D daily in 36,282 post-menopausal women. We assessed the effects of CaD on cardiovascular events, death, cancer and fracture in a randomized design- comparing CaD with placebo in 43% of women not using personal calcium or vitamin D supplements- and in a observational design- comparing women in the placebo group (44%) using personal calcium and vitamin D supplements with non-users. Incidence was assessed using Cox proportional hazards models, and results from the two study designs deemed concordant if the absolute difference in hazard ratios was ≤0.15. We also compared results from WHI CaD to those from the WHI Observational Study(WHI OS), which used similar methodology for analyses and recruited from the same population. Results In WHI CaD, for myocardial infarction and stroke, results of unadjusted and 6/8 covariate-controlled observational analyses (age-adjusted, multivariate-adjusted, propensity-adjusted, propensity-matched) were not concordant with the randomized design results. For death, hip and total fracture, colorectal and total cancer, unadjusted and covariate-controlled observational results were concordant with randomized results. For breast cancer, unadjusted and age-adjusted observational results were concordant with randomized results, but only 1/3 other covariate-controlled observational results were concordant with randomized results. Multivariate-adjusted results from WHI OS were concordant with randomized WHI CaD results for only 4/8 endpoints. Conclusions Results of randomized analyses in WHI CaD were concordant with observational analyses for 5/8 endpoints in WHI CaD and 4/8 endpoints in WHI OS. PMID:26440516

Missing observations in multiyear rotation sampling designs

NASA Technical Reports Server (NTRS)

Gbur, E. E.; Sielken, R. L., Jr. (Principal Investigator)

1982-01-01

Because Multiyear estimation of at-harvest stratum crop proportions is more efficient than single year estimation, the behavior of multiyear estimators in the presence of missing acquisitions was studied. Only the (worst) case when a segment proportion cannot be estimated for the entire year is considered. The effect of these missing segments on the variance of the at-harvest stratum crop proportion estimator is considered when missing segments are not replaced, and when missing segments are replaced by segments not sampled in previous years. The principle recommendations are to replace missing segments according to some specified strategy, and to use a sequential procedure for selecting a sampling design; i.e., choose an optimal two year design and then, based on the observed two year design after segment losses have been taken into account, choose the best possible three year design having the observed two year parent design.

The life cycles of six multi-center adaptive clinical trials focused on neurological emergencies developed for the Advancing Regulatory Science initiative of the National Institutes of Health and US Food and Drug Administration: Case studies from the Adaptive Designs Accelerating Promising Treatments Into Trials Project.

PubMed

Guetterman, Timothy C; Fetters, Michael D; Mawocha, Samkeliso; Legocki, Laurie J; Barsan, William G; Lewis, Roger J; Berry, Donald A; Meurer, William J

2017-01-01

Clinical trials are complicated, expensive, time-consuming, and frequently do not lead to discoveries that improve the health of patients with disease. Adaptive clinical trials have emerged as a methodology to provide more flexibility in design elements to better answer scientific questions regarding whether new treatments are efficacious. Limited observational data exist that describe the complex process of designing adaptive clinical trials. To address these issues, the Adaptive Designs Accelerating Promising Treatments Into Trials project developed six, tailored, flexible, adaptive, phase-III clinical trials for neurological emergencies, and investigators prospectively monitored and observed the processes. The objective of this work is to describe the adaptive design development process, the final design, and the current status of the adaptive trial designs that were developed. To observe and reflect upon the trial development process, we employed a rich, mixed methods evaluation that combined quantitative data from visual analog scale to assess attitudes about adaptive trials, along with in-depth qualitative data about the development process gathered from observations. The Adaptive Designs Accelerating Promising Treatments Into Trials team developed six adaptive clinical trial designs. Across the six designs, 53 attitude surveys were completed at baseline and after the trial planning process completed. Compared to baseline, the participants believed significantly more strongly that the adaptive designs would be accepted by National Institutes of Health review panels and non-researcher clinicians. In addition, after the trial planning process, the participants more strongly believed that the adaptive design would meet the scientific and medical goals of the studies. Introducing the adaptive design at early conceptualization proved critical to successful adoption and implementation of that trial. Involving key stakeholders from several scientific domains early in the process appears to be associated with improved attitudes towards adaptive designs over the life cycle of clinical trial development.

STRengthening analytical thinking for observational studies: the STRATOS initiative.

PubMed

Sauerbrei, Willi; Abrahamowicz, Michal; Altman, Douglas G; le Cessie, Saskia; Carpenter, James

2014-12-30

The validity and practical utility of observational medical research depends critically on good study design, excellent data quality, appropriate statistical methods and accurate interpretation of results. Statistical methodology has seen substantial development in recent times. Unfortunately, many of these methodological developments are ignored in practice. Consequently, design and analysis of observational studies often exhibit serious weaknesses. The lack of guidance on vital practical issues discourages many applied researchers from using more sophisticated and possibly more appropriate methods when analyzing observational studies. Furthermore, many analyses are conducted by researchers with a relatively weak statistical background and limited experience in using statistical methodology and software. Consequently, even 'standard' analyses reported in the medical literature are often flawed, casting doubt on their results and conclusions. An efficient way to help researchers to keep up with recent methodological developments is to develop guidance documents that are spread to the research community at large. These observations led to the initiation of the strengthening analytical thinking for observational studies (STRATOS) initiative, a large collaboration of experts in many different areas of biostatistical research. The objective of STRATOS is to provide accessible and accurate guidance in the design and analysis of observational studies. The guidance is intended for applied statisticians and other data analysts with varying levels of statistical education, experience and interests. In this article, we introduce the STRATOS initiative and its main aims, present the need for guidance documents and outline the planned approach and progress so far. We encourage other biostatisticians to become involved. © 2014 The Authors. Statistics in Medicine published by John Wiley & Sons, Ltd.

Skylab-4 visual observations project: Geological features of southwestern North America

NASA Technical Reports Server (NTRS)

Silver, L. T.

1975-01-01

Visual observations conducted by Skylab-4 crewmen on seven designated geological target areas and other targets of opportunity in parts of southwestern United States and northwestern Mexico were described. The experiments were designed to learn how effectively geologic features could be observed from orbit and what research information could be obtained from the observations when supported by ground studies. For the limited preparation they received, the crewmen demonstrated exceptional observational ability and produced outstanding photographic studies. They also formulated cogent opinions on how to improve future observational and photo-documentation techniques. From the photographs and other observations, it was possible to obtain significant research contributions to on-going field investigations. These contributions were integrated into other aspects of the ground investigations to the following topics: major faults, regional stratigraphy, occurrence of Precambrian crystalline rocks, mapping of Mesozoic volcanic rocks, regional geology.

Analytical Methods for a Learning Health System: 2. Design of Observational Studies

PubMed Central

Stoto, Michael; Oakes, Michael; Stuart, Elizabeth; Priest, Elisa L.; Savitz, Lucy

2017-01-01

The second paper in a series on how learning health systems can use routinely collected electronic health data (EHD) to advance knowledge and support continuous learning, this review summarizes study design approaches, including choosing appropriate data sources, and methods for design and analysis of natural and quasi-experiments. The primary strength of study design approaches described in this section is that they study the impact of a deliberate intervention in real-world settings, which is critical for external validity. These evaluation designs address estimating the counterfactual – what would have happened if the intervention had not been implemented. At the individual level, epidemiologic designs focus on identifying situations in which bias is minimized. Natural and quasi-experiments focus on situations where the change in assignment breaks the usual links that could lead to confounding, reverse causation, and so forth. And because these observational studies typically use data gathered for patient management or administrative purposes, the possibility of observation bias is minimized. The disadvantages are that one cannot necessarily attribute the effect to the intervention (as opposed to other things that might have changed), and the results do not indicate what about the intervention made a difference. Because they cannot rely on randomization to establish causality, program evaluation methods demand a more careful consideration of the “theory” of the intervention and how it is expected to play out. A logic model describing this theory can help to design appropriate comparisons, account for all influential variables in a model, and help to ensure that evaluation studies focus on the critical intermediate and long-term outcomes as well as possible confounders. PMID:29881745

Earth Observing Scanning Polarimeter (EOSP), phase B

NASA Technical Reports Server (NTRS)

1990-01-01

Evaluations performed during a Phase B study directed towards defining an optimal design for the Earth Observing Scanning Polarimeter (EOSP) instrument is summarized. An overview of the experiment approach is included which provides a summary of the scientific objectives, the background of the measurement approach, and the measurement method. In the instrumentation section, details of the design are discussed starting with the key instrument features required to accomplish the scientific objectives and a system characterization in terms of the Stokes vector/Mueller matrix formalism. This is followed by a detailing of the instrument design concept, the design of the individual elements of the system, the predicted performance, and a summary of appropriate instrument testing and calibration. The selected design makes use of key features of predecessor polarimeters and is fully compatible with the Earth Observing System spacecraft requirements.

Nonlinear observer designs for fuel cell power systems

NASA Astrophysics Data System (ADS)

Gorgun, Haluk

A fuel cell is an electrochemical device that combines hydrogen and oxygen, with the aid of electro-catalysts, to produce electricity. A fuel cell consists of a negatively charged anode, a positively charged cathode and an electrolyte, which transports protons or ions. A low temperature fuel cell has an electrical potential of about 0.7 Volt when generating a current density of 300--500 mA/cm2. Practical fuel cell power systems will require a combination of several cells in series (a stack) to satisfy the voltage requirements of specific applications. Fuel cells are suitable for a potentially wide variety of applications, from stationary power generation in the range of hundreds of megawatts to portable electronics in the range of a couple of watts. Efficient operation of a fuel cell system requires advanced feedback control designs. Reliable measurements from the system are necessary to implement such designs. However, most of the commercially available sensors do not operate properly in the reformate and humidified gas streams in fuel cell systems. Sensors working varying degrees of success are too big and costly, and sensors that are potentially low cost are not reliable or do not have the required life time [28]. Observer designs would eliminate sensor needs for measurements, and make feedback control implementable. Since the fuel cell system dynamics are highly nonlinear, observer design is not an easy task. In this study we aim to develop nonlinear observer design methods applicable to fuel cell systems. In part I of the thesis we design an observer to estimate the hydrogen partial pressure in the anode channel. We treat inlet partial pressure as an unknown slowly varying parameter and develop an adaptive observer that employs a nonlinear voltage injection term. However in this design Fuel Processing System (FPS) dynamics are not modelled, and their effect on the anode dynamics are treated as plant uncertainty. In part II of the thesis we study the FPS dynamics, and estimate not only hydrogen but also all other species in its reactors. We design nonlinear observers for the Catalytic Partial Oxidation (CPO), Water Gas Shift (WGS), and Preferential Oxidation (PROX), reactors in the FPS. The observers make use of temperature measurements (and possibly one more variable, such as pressure) to estimate the mole fractions of each species in the reactors. An advantage of these designs is that they are based on reaction invariants and do not rely on knowledge of reaction rate expressions. Finally, in part III, we illustrate how the designs of parts I and II can be incorporated in fault detection and estimation algorithms for common failures encountered in fuel cells, such as the cathode blower failure and the anode valve failure. For this task, we combine geometric tools with our observers.

Observing Protein & Energy Nutrition (OPEN) Study

Cancer.gov

The Observing Protein and Energy Nutrition (OPEN) Study was designed to assess dietary measurement error by comparing results from self-reported dietary intake data with four dietary biomarkers: doubly labeled water and urinary nitrogen, sodium, and potassium.

Using task analysis in healthcare design to improve clinical efficiency.

PubMed

Lu, Jun; Hignett, Sue

2009-01-01

To review the functionality of the proposed soiled workroom design for efficient and safe clinical activities. As part of a hospital refurbishment program, the planning team of a United Kingdom National Health Service hospital requested a review of a proposed standardized room design. A 7-day observational study was conducted in five clinical departments at three hospitals. Link analysis was used to record and analyze the movements among components, i.e., nursing staff, equipment/devices, and furniture. Fifty-four observations were recorded for 18 clinical tasks. The most frequent tasks were the disposal of urine and used urine bottles, and returning used commode chairs. Minor recommendations were made to improve the proposed design, and major revisions were suggested to address functionality problems. It was found that the proposed design did not offer the optimal layout for efficient and safe clinical activities. Link analysis was found to be effective for plotting the movements of the staff and accounting for the complexity of tasks. This ergonomic method, in combination with observational field studies, provided a simple and effective way to determine functional space requirements for clinical activities and should be used in all healthcare building design projects.

The within-subjects design in the study of facial expressions.

PubMed

Yik, Michelle; Widen, Sherri C; Russell, James A

2013-01-01

The common within-subjects design of studies on the recognition of emotion from facial expressions allows the judgement of one face to be influenced by previous faces, thus introducing the potential for artefacts. The present study (N=344) showed that the canonical "disgust face" was judged as disgusted, provided that the preceding set of faces included "anger expressions", but was judged as angry when the preceding set of faces excluded anger but instead included persons who looked sad or about to be sick. Chinese observers showed lower recognition of the "disgust face" than did American observers. Chinese observers also showed lower recognition of the "fear face" when responding in Chinese than in English.

Effects of imperfect test sensitivity and specificity on observational studies of influenza vaccine effectiveness.

PubMed

Jackson, Michael L; Rothman, Kenneth J

2015-03-10

The recently developed test-negative design is now standard for observational studies of influenza vaccine effectiveness (VE). It is unclear how influenza test misclassification biases test-negative VE estimates relative to VE estimates from traditional cohort or case-control studies. We simulated populations whose members may develop acute respiratory illness (ARI) due to influenza and to non-influenza pathogens. In these simulations, vaccination reduces the risk of influenza but not of non-influenza ARI. Influenza test sensitivity and specificity, risks of influenza and non-influenza ARI, and VE were varied across the simulations. In each simulation, we estimated influenza VE using a cohort design, a case-control design, and a test-negative design. In the absence of influenza test misclassification, all three designs accurately estimated influenza VE. In the presence of misclassification, all three designs underestimated VE. Bias in VE estimates was slightly greater in the test-negative design than in cohort or case-control designs. Assuming the use of highly sensitive and specific reverse-transcriptase polymerase chain reaction tests for influenza, bias in the test-negative studies was trivial across a wide range of realistic values for VE. Although influenza test misclassification causes more bias in test-negative studies than in traditional cohort or case-control studies, the difference is trivial for realistic combinations of attack rates, test sensitivity/specificity, and VE. Copyright © 2015 Elsevier Ltd. All rights reserved.

Clinical Research Methodology 2: Observational Clinical Research.

PubMed

Sessler, Daniel I; Imrey, Peter B

2015-10-01

Case-control and cohort studies are invaluable research tools and provide the strongest feasible research designs for addressing some questions. Case-control studies usually involve retrospective data collection. Cohort studies can involve retrospective, ambidirectional, or prospective data collection. Observational studies are subject to errors attributable to selection bias, confounding, measurement bias, and reverse causation-in addition to errors of chance. Confounding can be statistically controlled to the extent that potential factors are known and accurately measured, but, in practice, bias and unknown confounders usually remain additional potential sources of error, often of unknown magnitude and clinical impact. Causality-the most clinically useful relation between exposure and outcome-can rarely be definitively determined from observational studies because intentional, controlled manipulations of exposures are not involved. In this article, we review several types of observational clinical research: case series, comparative case-control and cohort studies, and hybrid designs in which case-control analyses are performed on selected members of cohorts. We also discuss the analytic issues that arise when groups to be compared in an observational study, such as patients receiving different therapies, are not comparable in other respects.

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

PubMed

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

2017-07-01

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

Boundary control for a flexible manipulator based on infinite dimensional disturbance observer

NASA Astrophysics Data System (ADS)

Jiang, Tingting; Liu, Jinkun; He, Wei

2015-07-01

This paper focuses on disturbance observer and boundary control design for the flexible manipulator in presence of both boundary disturbance and spatially distributed disturbance. Taking the infinite-dimensionality of the flexural dynamics into account, this study proposes a partial differential equation (PDE) model. Since the spatially distributed disturbance is infinite dimensional, it cannot be compensated by the typical disturbance observer, which is designed by finite dimensional approach. To estimate the spatially distributed disturbance, we propose a novel infinite dimensional disturbance observer (IDDO). Applying the IDDO as a feedforward compensator, a boundary control scheme is designed to regulate the joint position and eliminate the elastic vibration simultaneously. Theoretical analysis validates the stability of both the proposed disturbance observer and the boundary controller. The performance of the closed-loop system is demonstrated by numerical simulations.

Masked Visual Analysis: Minimizing Type I Error in Visually Guided Single-Case Design for Communication Disorders

ERIC Educational Resources Information Center

Byun, Tara McAllister; Hitchcock, Elaine R.; Ferron, John

2017-01-01

Purpose: Single-case experimental designs are widely used to study interventions for communication disorders. Traditionally, single-case experiments follow a response-guided approach, where design decisions during the study are based on participants' observed patterns of behavior. However, this approach has been criticized for its high rate of…

Preventing Smoking in Open Public Places in University Campus Settings: A Situational Crime Prevention Approach

ERIC Educational Resources Information Center

Sun, Jing; Prenzler, Tim; Buys, Nicholas; McMeniman, Marilyn

2012-01-01

Purpose: The purpose of the study was to evaluate the effectiveness of interventions using situational crime prevention approaches to reduce the smoking rate in outdoor areas of a university campus. Design/methodology/approach: A prospective intervention design was designed for the study. Surveys and observations were used to measure the impacts…

Sketching in Design Journals: An Analysis of Visual Representations in the Product Design Process

ERIC Educational Resources Information Center

Lau, Kimberly; Oehlberg, Lora; Agogino, Alice

2009-01-01

This paper explores the sketching behavior of designers and the role of sketching in the design process. Observations from a descriptive study of sketches provided in design journals, characterized by a protocol measuring sketching activities, are presented. A distinction is made between journals that are entirely tangible and those that contain…

Assessing Reflective Thinking in Solving Design Problems: The Development of a Questionnaire

ERIC Educational Resources Information Center

Hong, Yi-Chun; Choi, Ikseon

2015-01-01

Reflection is a critical factor in solving design problems. Using good methods to observe designers' reflection is essential to inform the design of the learning environments that support the development of design problem-solving skills. In this study, we have developed and validated a novel self-reporting questionnaire as an efficient instrument…

Using channelized Hotelling observers to quantify temporal effects of medical liquid crystal displays on detection performance

NASA Astrophysics Data System (ADS)

Platiša, Ljiljana; Goossens, Bart; Vansteenkiste, Ewout; Badano, Aldo; Philips, Wilfried

2010-02-01

Clinical practice is rapidly moving in the direction of volumetric imaging. Often, radiologists interpret these images in liquid crystal displays at browsing rates of 30 frames per second or higher. However, recent studies suggest that the slow response of the display can compromise image quality. In order to quantify the temporal effect of medical displays on detection performance, we investigate two designs of a multi-slice channelized Hotelling observer (msCHO) model in the task of detecting a single-slice signal in multi-slice simulated images. The design of msCHO models is inspired by simplifying assumptions about how humans observe while viewing in the stack-browsing mode. For comparison, we consider a standard CHO applied only on the slice where the signal is located, recently used in a similar study. We refer to it as a single-slice CHO (ssCHO). Overall, our results confirm previous findings that the slow response of displays degrades the detection performance of the observers. More specifically, the observed performance range of msCHO designs is higher compared to the ssCHO suggesting that the extent and rate of degradation, though significant, may be less drastic than previously estimated by the ssCHO. Especially, the difference between msCHO and ssCHO is more significant for higher browsing speeds than for slow image sequences or static images. This, together with their design criteria driven by the assumptions about humans, makes the msCHO models promising candidates for further studies aimed at building anthropomorphic observer models for the stack-mode image presentation.

? observer-based decentralised fuzzy control design for nonlinear interconnected systems: an application to vehicle dynamics

NASA Astrophysics Data System (ADS)

Latrach, Chedia; Kchaou, Mourad; Guéguen, Hervé

2017-05-01

In this study, a decentralised output learning control strategy for a class of nonlinear interconnected systems is studied. Based on Takagi-Sugeno fuzzy (TS) model to approximate the considered interconnected nonlinear systems, a decentralised observer-based control scheme is designed to override the external disturbances such that the ? performance is achieved. The appealing attributes of this approach include: (1) the closed-loop system exhibits a robustness against nonlinear interconnections and external disturbance, (2) by one-step procedure, the gain matrices of observer and controller are obtained on a single step. In simulation results, the controller design is evaluated on the steering stability of a car where the nonlinear model describes the side slip, roll and yaw motions of the automotive vehicle equipped with four-wheel-steering and active suspension.

Tinkering self-efficacy and team interaction on freshman engineering design teams

NASA Astrophysics Data System (ADS)

Richardson, Arlisa Labrie

This study utilizes Bandura's theory of self-efficacy as a framework to examine the development of tinkering skills white working on a freshman engineering design team. The four sources of self-efficacy were analyzed in the context of tinkering within the design team. The research question, 'Does tinkering self-efficacy change for female students during the Freshman Engineering Design class while working on mixed sex teams?', was addressed using quantitative data collection and field observations. Approximately 41 students enrolled in a freshman engineering design class at a public university in the southwest participated by providing self-reports about their tinkering involvement during each design project. In addition, three mixed-sex student teams were observed while working to complete the course design projects. An observation protocol based on Bandura's sources of self efficacy, was used to document tinkering interactions within the three observed teams. The results revealed that Bandura's sources of self-efficacy influenced tinkering involvement. The self-efficacy source, performance accomplishment measured through prior tinkering experience, was the most influential on tinkering involvement. Unlike Bandura's ranking of influence, verbal persuasion was shown to correlate with more tinkering behaviors than the observation of others. The number of females on a team had no impact on tinkering involvement. Tinkering involvement did not change as students progressed from one project to another. However, the competitive nature of the design project appeared to have a negative impact on tinkering involvement and the division of tasks within the team. In addition, a difference was found in the female students' perception of their tinkering involvement and observation of their tinkering involvement. The findings suggest that effective implementation of teamwork including teamwork preparation, more emphasis on the design process and the elimination of competition between teams are necessary to create a more equitable learning environment.

a Study of Co-Planing Technology of Spaceborne, Airborne and Ground Remote Sensing Detecting Resource, Driven by Disaster Emergency Task

NASA Astrophysics Data System (ADS)

Yu, F.; Chen, H.; Tu, K.; Wen, Q.; He, J.; Gu, X.; Wang, Z.

2018-04-01

Facing the monitoring needs of emergency responses to major disasters, combining the disaster information acquired at the first time after the disaster and the dynamic simulation result of the disaster chain evolution process, the overall plan for coordinated planning of spaceborne, airborne and ground observation resources have been designed. Based on the analysis of the characteristics of major disaster observation tasks, the key technologies of spaceborne, airborne and ground collaborative observation project are studied. For different disaster response levels, the corresponding workflow tasks are designed. On the basis of satisfying different types of disaster monitoring demands, the existing multi-satellite collaborative observation planning algorithms are compared, analyzed, and optimized.

[Diversity and frequency of scientific research design and statistical methods in the "Arquivos Brasileiros de Oftalmologia": a systematic review of the "Arquivos Brasileiros de Oftalmologia"--1993-2002].

PubMed

Crosta, Fernando; Nishiwaki-Dantas, Maria Cristina; Silvino, Wilmar; Dantas, Paulo Elias Correa

2005-01-01

To verify the frequency of study design, applied statistical analysis and approval by institutional review offices (Ethics Committee) of articles published in the "Arquivos Brasileiros de Oftalmologia" during a 10-year interval, with later comparative and critical analysis by some of the main international journals in the field of Ophthalmology. Systematic review without metanalysis was performed. Scientific papers published in the "Arquivos Brasileiros de Oftalmologia" between January 1993 and December 2002 were reviewed by two independent reviewers and classified according to the applied study design, statistical analysis and approval by the institutional review offices. To categorize those variables, a descriptive statistical analysis was used. After applying inclusion and exclusion criteria, 584 articles for evaluation of statistical analysis and, 725 articles for evaluation of study design were reviewed. Contingency table (23.10%) was the most frequently applied statistical method, followed by non-parametric tests (18.19%), Student's t test (12.65%), central tendency measures (10.60%) and analysis of variance (9.81%). Of 584 reviewed articles, 291 (49.82%) presented no statistical analysis. Observational case series (26.48%) was the most frequently used type of study design, followed by interventional case series (18.48%), observational case description (13.37%), non-random clinical study (8.96%) and experimental study (8.55%). We found a higher frequency of observational clinical studies, lack of statistical analysis in almost half of the published papers. Increase in studies with approval by institutional review Ethics Committee was noted since it became mandatory in 1996.

Validation of an image-based technique to assess the perceptual quality of clinical chest radiographs with an observer study

NASA Astrophysics Data System (ADS)

Lin, Yuan; Choudhury, Kingshuk R.; McAdams, H. Page; Foos, David H.; Samei, Ehsan

2014-03-01

We previously proposed a novel image-based quality assessment technique1 to assess the perceptual quality of clinical chest radiographs. In this paper, an observer study was designed and conducted to systematically validate this technique. Ten metrics were involved in the observer study, i.e., lung grey level, lung detail, lung noise, riblung contrast, rib sharpness, mediastinum detail, mediastinum noise, mediastinum alignment, subdiaphragm-lung contrast, and subdiaphragm area. For each metric, three tasks were successively presented to the observers. In each task, six ROI images were randomly presented in a row and observers were asked to rank the images only based on a designated quality and disregard the other qualities. A range slider on the top of the images was used for observers to indicate the acceptable range based on the corresponding perceptual attribute. Five boardcertificated radiologists from Duke participated in this observer study on a DICOM calibrated diagnostic display workstation and under low ambient lighting conditions. The observer data were analyzed in terms of the correlations between the observer ranking orders and the algorithmic ranking orders. Based on the collected acceptable ranges, quality consistency ranges were statistically derived. The observer study showed that, for each metric, the averaged ranking orders of the participated observers were strongly correlated with the algorithmic orders. For the lung grey level, the observer ranking orders completely accorded with the algorithmic ranking orders. The quality consistency ranges derived from this observer study were close to these derived from our previous study. The observer study indicates that the proposed image-based quality assessment technique provides a robust reflection of the perceptual image quality of the clinical chest radiographs. The derived quality consistency ranges can be used to automatically predict the acceptability of a clinical chest radiograph.

Real-world research and the role of observational data in the field of gynaecology - a practical review.

PubMed

Heikinheimo, Oskari; Bitzer, Johannes; García Rodríguez, Luis

2017-08-01

In the context of women's health, we examine (1) the role that observational ('real-world') studies have in overcoming limitations of randomised clinical trials, (2) the relative advantages and disadvantages of different study designs, (3) the importance of outcome data from observational studies when making health-economic or clinical decisions, and (4) provide insights into changing perceptions of observational clinical data. PubMed and internet searches were used to identify (i) guidance and expert commentary on designing, conducting, analysing, and reporting clinical trials or observational studies, (ii) supporting evidence of the rapid growth of observational ('real world') studies and publications since the turn of millennium in the fields of contraception, reproductive health, obstetrics or gynaecology. The rapidly growing use and validation of large, computerised medical records and related databases (e.g., health insurance or national registries) have played a major part in changing perceptions of observational data among researchers and clinicians. In the past 10 years, a distinct increase in the number of observational studies published tends to confirm their growing acceptance, appreciation and use. Observational studies can provide information that is impossible or infeasible to obtain otherwise (e.g., impractical, very expensive, or ethically unacceptable). Greater understanding, dissemination, uptake and use of observational data might be expected to drive ongoing evolution of research, data collection, analysis, and validation, in turn improving quality and therefore credibility, utility, and further application by clinicians.

Designing clinical trials for amblyopia

PubMed Central

Holmes, Jonathan M.

2015-01-01

Randomized clinical trial (RCT) study design leads to one of the highest levels of evidence, and is a preferred study design over cohort studies, because randomization reduces bias and maximizes the chance that even unknown confounding factors will be balanced between treatment groups. Recent randomized clinical trials and observational studies in amblyopia can be taken together to formulate an evidence-based approach to amblyopia treatment, which is presented in this review. When designing future clinical studies of amblyopia treatment, issues such as regression to the mean, sample size and trial duration must be considered, since each may impact study results and conclusions. PMID:25752747

The Growing Awareness Inventory: Building Capacity for Culturally Responsive Science and Mathematics with a Structured Observation Protocol

ERIC Educational Resources Information Center

Brown, Julie C.; Crippen, Kent J.

2016-01-01

This study represents a first iteration in the design process of the Growing Awareness Inventory (GAIn), a structured observation protocol for building the awareness of preservice teachers (PSTs) for resources in mathematics and science classrooms that can be used for culturally responsive pedagogy (CRP). The GAIn is designed to develop awareness…

Adaptive extended-state observer-based fault tolerant attitude control for spacecraft with reaction wheels

NASA Astrophysics Data System (ADS)

Ran, Dechao; Chen, Xiaoqian; de Ruiter, Anton; Xiao, Bing

2018-04-01

This study presents an adaptive second-order sliding control scheme to solve the attitude fault tolerant control problem of spacecraft subject to system uncertainties, external disturbances and reaction wheel faults. A novel fast terminal sliding mode is preliminarily designed to guarantee that finite-time convergence of the attitude errors can be achieved globally. Based on this novel sliding mode, an adaptive second-order observer is then designed to reconstruct the system uncertainties and the actuator faults. One feature of the proposed observer is that the design of the observer does not necessitate any priori information of the upper bounds of the system uncertainties and the actuator faults. In view of the reconstructed information supplied by the designed observer, a second-order sliding mode controller is developed to accomplish attitude maneuvers with great robustness and precise tracking accuracy. Theoretical stability analysis proves that the designed fault tolerant control scheme can achieve finite-time stability of the closed-loop system, even in the presence of reaction wheel faults and system uncertainties. Numerical simulations are also presented to demonstrate the effectiveness and superiority of the proposed control scheme over existing methodologies.

Visual implant elastomer mark retention through metamorphosis in amphibian larvae

USGS Publications Warehouse

Campbell Grant, Evan H.

2008-01-01

Questions in population ecology require the study of marked animals, and marks are assumed to be permanent and not overlooked by observers. I evaluated retention through metamorphosis of visual implant elastomer marks in larval salamanders and frogs and assessed error in observer identification of these marks. I found 1) individual marks were not retained in larval wood frogs (Rana sylvatica), whereas only small marks were likely to be retained in larval salamanders (Eurycea bislineata), and 2) observers did not always correctly identify marked animals. Evaluating the assumptions of marking protocols is important in the design phase of a study so that correct inference can be made about the population processes of interest. This guidance should be generally useful to the design of mark–recapture studies, with particular application to studies of larval amphibians.

Modeling false positive detections in species occurrence data under different study designs.

PubMed

Chambert, Thierry; Miller, David A W; Nichols, James D

2015-02-01

The occurrence of false positive detections in presence-absence data, even when they occur infrequently, can lead to severe bias when estimating species occupancy patterns. Building upon previous efforts to account for this source of observational error, we established a general framework to model false positives in occupancy studies and extend existing modeling approaches to encompass a broader range of sampling designs. Specifically, we identified three common sampling designs that are likely to cover most scenarios encountered by researchers. The different designs all included ambiguous detections, as well as some known-truth data, but their modeling differed in the level of the model hierarchy at which the known-truth information was incorporated (site level or observation level). For each model, we provide the likelihood, as well as R and BUGS code needed for implementation. We also establish a clear terminology and provide guidance to help choosing the most appropriate design and modeling approach.

Developing Elementary Math and Science Process Skills Through Engineering Design Instruction

NASA Astrophysics Data System (ADS)

Strong, Matthew G.

This paper examines how elementary students can develop math and science process skills through an engineering design approach to instruction. The performance and development of individual process skills overall and by gender were also examined. The study, preceded by a pilot, took place in a grade four extracurricular engineering design program in a public, suburban school district. Students worked in pairs and small groups to design and construct airplane models from styrofoam, paper clips, and toothpicks. The development and performance of process skills were assessed through a student survey of learning gains, an engineering design packet rubric (student work), observation field notes, and focus group notes. The results indicate that students can significantly develop process skills, that female students may develop process skills through engineering design better than male students, and that engineering design is most helpful for developing the measuring, suggesting improvements, and observing process skills. The study suggests that a more regular engineering design program or curriculum could be beneficial for students' math and science abilities both in this school and for the elementary field as a whole.

A comparison of methods to estimate future sub-daily design rainfall

NASA Astrophysics Data System (ADS)

Li, J.; Johnson, F.; Evans, J.; Sharma, A.

2017-12-01

Warmer temperatures are expected to increase extreme short-duration rainfall due to the increased moisture-holding capacity of the atmosphere. While attention has been paid to the impacts of climate change on future design rainfalls at daily or longer time scales, the potential changes in short duration design rainfalls have been often overlooked due to the limited availability of sub-daily projections and observations. This study uses a high-resolution regional climate model (RCM) to predict the changes in sub-daily design rainfalls for the Greater Sydney region in Australia. Sixteen methods for predicting changes to sub-daily future extremes are assessed based on different options for bias correction, disaggregation and frequency analysis. A Monte Carlo cross-validation procedure is employed to evaluate the skill of each method in estimating the design rainfall for the current climate. It is found that bias correction significantly improves the accuracy of the design rainfall estimated for the current climate. For 1 h events, bias correcting the hourly annual maximum rainfall simulated by the RCM produces design rainfall closest to observations, whereas for multi-hour events, disaggregating the daily rainfall total is recommended. This suggests that the RCM fails to simulate the observed multi-duration rainfall persistence, which is a common issue for most climate models. Despite the significant differences in the estimated design rainfalls between different methods, all methods lead to an increase in design rainfalls across the majority of the study region.

Estimating the Occurrence of Child Maltreatment and Risk-Factor Effects: Benefits of a Mixed-Design Strategy in Epidemiologic Research.

ERIC Educational Resources Information Center

Bertolli, Jeanne; And Others

1995-01-01

This article discusses methodologic limitations of four observational study designs (ecologic, case-control, cross-sectional, and cohort) that dominate the child abuse and neglect literature and identifies key features of an "ideal" study of child maltreatment. It proposes a new mixed-design strategy, which improves ability to identify child…

Solar System Science with the Twinkle Space Mission

NASA Astrophysics Data System (ADS)

Bowles, N.; Lindsay, S.; Tessenyi, M.; Tinetti, G.; Savini, G.; Tennyson, J.; Pascale, E.; Jason, S.; Vora, A.

2017-09-01

Twinkle is a space-based telescope mission designed for the spectroscopic observation (0.4 to 4.5 μm) of exoplanet atmospheres and Solar System objects. The system design and mission implementation are based on existing, well studied concepts pioneered by Surrey Satellite Technology Ltd for low-Earth orbit Earth Observation satellites, supported by a novel international access model to allow facility access to researchers worldwide. Whilst Twinkle's primary science goal is the observation of exoplanet atmospheres its wide spectroscopic range and photometric stability also make it a unique platform for the observation of Solar system objects.

Optimizing the Design of Preprinted Orders for Ambulatory Chemotherapy: Combining Oncology, Human Factors, and Graphic Design

PubMed Central

Jeon, Jennifer; White, Rachel E.; Hunt, Richard G.; Cassano-Piché, Andrea L.; Easty, Anthony C.

2012-01-01

Purpose: To establish a set of guidelines for developing ambulatory chemotherapy preprinted orders. Methods: Multiple methods were used to develop the preprinted order guidelines. These included (A) a comprehensive literature review and an environmental scan; (B) analyses of field study observations and incident reports; (C) critical review of evidence from the literature and the field study observation analyses; (D) review of the draft guidelines by a clinical advisory group; and (E) collaboration with graphic designers to develop sample preprinted orders, refine the design guidelines, and format the resulting content. Results: The Guidelines for Developing Ambulatory Chemotherapy Preprinted Orders, which consist of guidance on the design process, content, and graphic design elements of ambulatory chemotherapy preprinted orders, have been established. Conclusion: Health care is a safety critical, dynamic, and complex sociotechnical system. Identifying safety risks in such a system and effectively addressing them often require the expertise of multiple disciplines. This study illustrates how human factors professionals, clinicians, and designers can leverage each other's expertise to uncover commonly overlooked patient safety hazards and to provide health care professionals with innovative, practical, and user-centered tools to minimize those hazards. PMID:23077436

Optimizing the design of preprinted orders for ambulatory chemotherapy: combining oncology, human factors, and graphic design.

PubMed

Jeon, Jennifer; White, Rachel E; Hunt, Richard G; Cassano-Piché, Andrea L; Easty, Anthony C

2012-03-01

To establish a set of guidelines for developing ambulatory chemotherapy preprinted orders. Multiple methods were used to develop the preprinted order guidelines. These included (A) a comprehensive literature review and an environmental scan; (B) analyses of field study observations and incident reports; (C) critical review of evidence from the literature and the field study observation analyses; (D) review of the draft guidelines by a clinical advisory group; and (E) collaboration with graphic designers to develop sample preprinted orders, refine the design guidelines, and format the resulting content. The Guidelines for Developing Ambulatory Chemotherapy Preprinted Orders, which consist of guidance on the design process, content, and graphic design elements of ambulatory chemotherapy preprinted orders, have been established. Health care is a safety critical, dynamic, and complex sociotechnical system. Identifying safety risks in such a system and effectively addressing them often require the expertise of multiple disciplines. This study illustrates how human factors professionals, clinicians, and designers can leverage each other's expertise to uncover commonly overlooked patient safety hazards and to provide health care professionals with innovative, practical, and user-centered tools to minimize those hazards.

Observer detection of image degradation caused by irreversible data compression processes

NASA Astrophysics Data System (ADS)

Chen, Ji; Flynn, Michael J.; Gross, Barry; Spizarny, David

1991-05-01

Irreversible data compression methods have been proposed to reduce the data storage and communication requirements of digital imaging systems. In general, the error produced by compression increases as an algorithm''s compression ratio is increased. We have studied the relationship between compression ratios and the detection of induced error using radiologic observers. The nature of the errors was characterized by calculating the power spectrum of the difference image. In contrast with studies designed to test whether detected errors alter diagnostic decisions, this study was designed to test whether observers could detect the induced error. A paired-film observer study was designed to test whether induced errors were detected. The study was conducted with chest radiographs selected and ranked for subtle evidence of interstitial disease, pulmonary nodules, or pneumothoraces. Images were digitized at 86 microns (4K X 5K) and 2K X 2K regions were extracted. A full-frame discrete cosine transform method was used to compress images at ratios varying between 6:1 and 60:1. The decompressed images were reprinted next to the original images in a randomized order with a laser film printer. The use of a film digitizer and a film printer which can reproduce all of the contrast and detail in the original radiograph makes the results of this study insensitive to instrument performance and primarily dependent on radiographic image quality. The results of this study define conditions for which errors associated with irreversible compression cannot be detected by radiologic observers. The results indicate that an observer can detect the errors introduced by this compression algorithm for compression ratios of 10:1 (1.2 bits/pixel) or higher.

The life cycles of six multi-center adaptive clinical trials focused on neurological emergencies developed for the Advancing Regulatory Science initiative of the National Institutes of Health and US Food and Drug Administration: Case studies from the Adaptive Designs Accelerating Promising Treatments Into Trials Project

PubMed Central

Guetterman, Timothy C; Fetters, Michael D; Mawocha, Samkeliso; Legocki, Laurie J; Barsan, William G; Lewis, Roger J; Berry, Donald A; Meurer, William J

2017-01-01

Objectives: Clinical trials are complicated, expensive, time-consuming, and frequently do not lead to discoveries that improve the health of patients with disease. Adaptive clinical trials have emerged as a methodology to provide more flexibility in design elements to better answer scientific questions regarding whether new treatments are efficacious. Limited observational data exist that describe the complex process of designing adaptive clinical trials. To address these issues, the Adaptive Designs Accelerating Promising Treatments Into Trials project developed six, tailored, flexible, adaptive, phase-III clinical trials for neurological emergencies, and investigators prospectively monitored and observed the processes. The objective of this work is to describe the adaptive design development process, the final design, and the current status of the adaptive trial designs that were developed. Methods: To observe and reflect upon the trial development process, we employed a rich, mixed methods evaluation that combined quantitative data from visual analog scale to assess attitudes about adaptive trials, along with in-depth qualitative data about the development process gathered from observations. Results: The Adaptive Designs Accelerating Promising Treatments Into Trials team developed six adaptive clinical trial designs. Across the six designs, 53 attitude surveys were completed at baseline and after the trial planning process completed. Compared to baseline, the participants believed significantly more strongly that the adaptive designs would be accepted by National Institutes of Health review panels and non-researcher clinicians. In addition, after the trial planning process, the participants more strongly believed that the adaptive design would meet the scientific and medical goals of the studies. Conclusion: Introducing the adaptive design at early conceptualization proved critical to successful adoption and implementation of that trial. Involving key stakeholders from several scientific domains early in the process appears to be associated with improved attitudes towards adaptive designs over the life cycle of clinical trial development. PMID:29085638

An Introduction to Propensity Score Methods for Reducing the Effects of Confounding in Observational Studies

ERIC Educational Resources Information Center

Austin, Peter C.

2011-01-01

The propensity score is the probability of treatment assignment conditional on observed baseline characteristics. The propensity score allows one to design and analyze an observational (nonrandomized) study so that it mimics some of the particular characteristics of a randomized controlled trial. In particular, the propensity score is a balancing…

Disturbance observer-based adaptive sliding mode hybrid projective synchronisation of identical fractional-order financial systems

NASA Astrophysics Data System (ADS)

Khan, Ayub; Tyagi, Arti

2018-05-01

In this paper, we have studied the hybrid projective synchronisation for incommensurate, integer and commensurate fractional-order financial systems with unknown disturbance. To tackle the problem of unknown bounded disturbance, fractional-order disturbance observer is designed to approximate the unknown disturbance. Further, we have introduced simple sliding mode surface and designed adaptive sliding mode controllers incorporating with the designed fractional-order disturbance observer to achieve a bounded hybrid projective synchronisation between two identical fractional-order financial model with different initial conditions. It is shown that the slave system with disturbance can be synchronised with the projection of the master system generated through state transformation. Simulation results are presented to ensure the validity and effectiveness of the proposed sliding mode control scheme in the presence of external bounded unknown disturbance. Also, synchronisation error for commensurate, integer and incommensurate fractional-order financial systems is studied in numerical simulation.

Describing and Modeling Workflow and Information Flow in Chronic Disease Care

PubMed Central

Unertl, Kim M.; Weinger, Matthew B.; Johnson, Kevin B.; Lorenzi, Nancy M.

2009-01-01

Objectives The goal of the study was to develop an in-depth understanding of work practices, workflow, and information flow in chronic disease care, to facilitate development of context-appropriate informatics tools. Design The study was conducted over a 10-month period in three ambulatory clinics providing chronic disease care. The authors iteratively collected data using direct observation and semi-structured interviews. Measurements The authors observed all aspects of care in three different chronic disease clinics for over 150 hours, including 157 patient-provider interactions. Observation focused on interactions among people, processes, and technology. Observation data were analyzed through an open coding approach. The authors then developed models of workflow and information flow using Hierarchical Task Analysis and Soft Systems Methodology. The authors also conducted nine semi-structured interviews to confirm and refine the models. Results The study had three primary outcomes: models of workflow for each clinic, models of information flow for each clinic, and an in-depth description of work practices and the role of health information technology (HIT) in the clinics. The authors identified gaps between the existing HIT functionality and the needs of chronic disease providers. Conclusions In response to the analysis of workflow and information flow, the authors developed ten guidelines for design of HIT to support chronic disease care, including recommendations to pursue modular approaches to design that would support disease-specific needs. The study demonstrates the importance of evaluating workflow and information flow in HIT design and implementation. PMID:19717802

Stroke prevention in atrial fibrillation: re-defining 'real-world data' within the broader data universe.

PubMed

Fanaroff, Alexander C; Steffel, Jan; Alexander, John H; Lip, Gregory Y H; Califf, Robert M; Lopes, Renato D

2018-04-23

Real-world data (RWD) has been defined as data generated outside of traditional randomized clinical trials (RCTs). Though RWD has received increasing attention from regulatory authorities and professional societies, dividing evidence into that derived from 'real-world' vs. 'non-real-world' sources provides only one element of a much larger framework for evidence evaluation. Evidence should be evaluated on the source of the data, the method of treatment allocation (whether any intervention being evaluated was assigned or simply observed as used in practice) and the context in which the evidence was generated (overall study design). Under this framework, RWD refers only to data source, and a study incorporates RWD when it primarily uses data collected for non-research purposes, such as insurance claims data or the electronic health record, regardless of study design. Separation of study design, data source, and context enables parallel evaluation of two critical elements: (i) whether a study can support claims of causal inference, which can be assured with a high degree of confidence only in studies where patients are assigned treatments by protocol; and (ii) whether the study population and clinical context mirror clinical practice, a strength of observational studies using data from clinical practice or administrative claims. In this review, we describe the strengths and weaknesses of observational and non-observational studies, and studies involving RWD and non-RWD, through the lens of anticoagulation for atrial fibrillation (AF). Observational studies employing RWD are useful for describing how oral anticoagulants are used in clinical practice, but generally cannot be used to make claims regarding comparative treatment effects. Questions regarding treatment effect generally are best answered through an RCT, and additional pragmatic RCTs are needed to compare different antithrombotic agents for the prevention of thrombotic events in AF.

The importance of replication in wildlife research

USGS Publications Warehouse

Johnson, D.H.

2002-01-01

Wildlife ecology and management studies have been widely criticized for deficiencies in design or analysis. Manipulative experiments--with controls, randomization, and replication in space and time--provide powerful ways of learning about natural systems and establishing causal relationships, but such studies are rare in our field. Observational studies and sample surveys are more common; they also require appropriate design and analysis. More important than the design and analysis of individual studies is metareplication: replication of entire studies. Similar conclusions obtained from studies of the same phenomenon conducted under widely differing conditions will give us greater confidence in the generality of those findings than would any single study, however well designed and executed.

Effect of component design in retrieved bipolar hip hemiarthroplasty systems.

PubMed

Hess, Matthew D; Baker, Erin A; Salisbury, Meagan R; Kaplan, Lige M; Greene, Ryan T; Greene, Perry W

2013-09-01

Primary articulation of bipolar hemiarthroplasty systems is at the femoral head-liner interface. The purpose of this study was to compare observed damage modes on 36 retrieved bipolar systems with implant, demographic, intraoperative, and radiographic data to elucidate the effects of component design, specifically locking mechanism, on clinical performance. Retrieved bipolar hip hemiarthroplasty systems of 3 different design types were obtained, disassembled, and evaluated macro- and microscopically for varying modes of wear, including abrasion, burnishing, embedding, scratching, and pitting. Clinical record review and radiographic analysis were performed by a senior orthopedic surgery resident. Average bipolar hip hemiarthroplasty system term of service was 46 months (range, 0.27-187 months). All devices contained wear debris captured within the articulating space between the femoral head and liner. In 31% of patients without infection, lucency was observed on immediate prerevision radiographs. The system with a leaf locking mechanism showed significantly increased radiographically observed osteolysis (P=.03) compared with a system with a stopper ring locking mechanism. In addition, implant design and observed damage modes, including pitting and third-body particle embedding, were significantly associated with radiographically observed osteolysis. Copyright 2013, SLACK Incorporated.

Osteoporosis therapies: evidence from health-care databases and observational population studies.

PubMed

Silverman, Stuart L

2010-11-01

Osteoporosis is a well-recognized disease with severe consequences if left untreated. Randomized controlled trials are the most rigorous method for determining the efficacy and safety of therapies. Nevertheless, randomized controlled trials underrepresent the real-world patient population and are costly in both time and money. Modern technology has enabled researchers to use information gathered from large health-care or medical-claims databases to assess the practical utilization of available therapies in appropriate patients. Observational database studies lack randomization but, if carefully designed and successfully completed, can provide valuable information that complements results obtained from randomized controlled trials and extends our knowledge to real-world clinical patients. Randomized controlled trials comparing fracture outcomes among osteoporosis therapies are difficult to perform. In this regard, large observational database studies could be useful in identifying clinically important differences among therapeutic options. Database studies can also provide important information with regard to osteoporosis prevalence, health economics, and compliance and persistence with treatment. This article describes the strengths and limitations of both randomized controlled trials and observational database studies, discusses considerations for observational study design, and reviews a wealth of information generated by database studies in the field of osteoporosis.

ADAPTIVE MATCHING IN RANDOMIZED TRIALS AND OBSERVATIONAL STUDIES

PubMed Central

van der Laan, Mark J.; Balzer, Laura B.; Petersen, Maya L.

2014-01-01

SUMMARY In many randomized and observational studies the allocation of treatment among a sample of n independent and identically distributed units is a function of the covariates of all sampled units. As a result, the treatment labels among the units are possibly dependent, complicating estimation and posing challenges for statistical inference. For example, cluster randomized trials frequently sample communities from some target population, construct matched pairs of communities from those included in the sample based on some metric of similarity in baseline community characteristics, and then randomly allocate a treatment and a control intervention within each matched pair. In this case, the observed data can neither be represented as the realization of n independent random variables, nor, contrary to current practice, as the realization of n/2 independent random variables (treating the matched pair as the independent sampling unit). In this paper we study estimation of the average causal effect of a treatment under experimental designs in which treatment allocation potentially depends on the pre-intervention covariates of all units included in the sample. We define efficient targeted minimum loss based estimators for this general design, present a theorem that establishes the desired asymptotic normality of these estimators and allows for asymptotically valid statistical inference, and discuss implementation of these estimators. We further investigate the relative asymptotic efficiency of this design compared with a design in which unit-specific treatment assignment depends only on the units’ covariates. Our findings have practical implications for the optimal design and analysis of pair matched cluster randomized trials, as well as for observational studies in which treatment decisions may depend on characteristics of the entire sample. PMID:25097298

Fuzzy model-based observers for fault detection in CSTR.

PubMed

Ballesteros-Moncada, Hazael; Herrera-López, Enrique J; Anzurez-Marín, Juan

2015-11-01

Under the vast variety of fuzzy model-based observers reported in the literature, what would be the properone to be used for fault detection in a class of chemical reactor? In this study four fuzzy model-based observers for sensor fault detection of a Continuous Stirred Tank Reactor were designed and compared. The designs include (i) a Luenberger fuzzy observer, (ii) a Luenberger fuzzy observer with sliding modes, (iii) a Walcott-Zak fuzzy observer, and (iv) an Utkin fuzzy observer. A negative, an oscillating fault signal, and a bounded random noise signal with a maximum value of ±0.4 were used to evaluate and compare the performance of the fuzzy observers. The Utkin fuzzy observer showed the best performance under the tested conditions. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

Proof of Concept in Disrupted Tactical Networking

DTIC Science & Technology

2017-09-01

because of the risk of detection. In this study , we design projectile-based mesh networking prototypes as one potential type of short-living network...to communicate because of the risk of detection. In this study , we design projectile-based mesh networking prototypes as one potential type of short...reader with a background in systems-theory. This study is designed using systems theory and uses systems theory as a lens through which to observe

Candidate configuration trade study, Stellar-inertial Measurement Systems (SIMS) for an Earth Observation Satellite (EOS)

NASA Technical Reports Server (NTRS)

Ogletree, G.; Coccoli, J.; Mckern, R.; Smith, M.; White, R.

1972-01-01

The results of analytical and simulation studies of the stellar-inertial measurement system (SIMS) for an earth observation satellite are presented. Subsystem design analyses and sensor design trades are reported. Three candidate systems are considered: (1) structure-mounted gyros with structure-mounted star mapper, (2) structure-mounted gyros with gimbaled star tracker, and (3) gimbaled gyros with structure-mounted star mapper. The purpose of the study is to facilitate the decisions pertaining to gimbaled versus structure-mounted gyros and star sensors, and combinations of systems suitable for the EOS satellite.

Observational Versus Experimental Studies: What’s the Evidence for a Hierarchy?

PubMed Central

Concato, John

2004-01-01

Summary: The tenets of evidence-based medicine include an emphasis on hierarchies of research design (i.e., study architecture). Often, a single randomized, controlled trial is considered to provide “truth,” whereas results from any observational study are viewed with suspicion. This paper describes information that contradicts and discourages such a rigid approach to evaluating the quality of research design. Unless a more balanced strategy evolves, new claims of methodological authority may be just as problematic as the traditional claims of medical authority that have been criticized by proponents of evidence-based medicine. PMID:15717036

A pragmatic observational feasibility study on integrated treatment for musculoskeletal disorders: Design and protocol.

PubMed

Hu, Xiao-yang; Hughes, John; Fisher, Peter; Lorenc, Ava; Purtell, Rachel; Park, A-La; Robinson, Nicola

2016-02-01

Musculoskeletal disorders (MSD) comprise a wide range of conditions, associated with an enormous pain and impaired mobility, and are affecting people's lives and work. Management of musculoskeletal disorders typically involves a multidisciplinary team approach. Positive findings have been found in previous studies evaluating the effectiveness of complementary therapies, though little attention has been paid to evaluating of the effectiveness of integrated packages of care combining conventional and complementary approaches for musculoskeletal conditions in a National Health Service (NHS) setting. To determine the feasibility of all aspects of a pragmatic observational study designed: (1) to evaluate the effectiveness and cost effectiveness of integrated treatments for MSDs in an integrated NHS hospital in the UK; (2) to determine the acceptability of the study design and research process to patients; (3) to explore patients' expectation and experience of receiving integrated treatments. This is an observational feasibility study, with 1-year recruitment and 1-year follow-up, conducted in Royal London Hospital for Integrated Medicine, University College London Hospital Trust, UK. All eligible patients with MSDs newly referred to the hospital were included in the study. Interventions are integrated packages of care (conventional and complementary) as currently provided in the hospital. SF-36™ Health Survey, short form Brief Pain Inventory, Visual Analogue Scale, and modified Client Service Receipt Inventory will be assessed at 4/5 time points. Semi-structured interview/focus group will be carried out before treatment, and 1 year after commence of treatment. We intend to conduct a pragmatic observational study of integrated medical treatment of MSDs at a public sector hospital. It will inform the design of a future trial including recruitment, retention, suitability of the outcome measures and patients experiences.

Unsymmetric Lanczos model reduction and linear state function observer for flexible structures

NASA Technical Reports Server (NTRS)

Su, Tzu-Jeng; Craig, Roy R., Jr.

1991-01-01

This report summarizes part of the research work accomplished during the second year of a two-year grant. The research, entitled 'Application of Lanczos Vectors to Control Design of Flexible Structures' concerns various ways to use Lanczos vectors and Krylov vectors to obtain reduced-order mathematical models for use in the dynamic response analyses and in control design studies. This report presents a one-sided, unsymmetric block Lanczos algorithm for model reduction of structural dynamics systems with unsymmetric damping matrix, and a control design procedure based on the theory of linear state function observers to design low-order controllers for flexible structures.

Propensity score models in observational comparative effectiveness studies: cornerstone of design or statistical afterthought?

PubMed

Robinson, John W

2012-03-01

Propensity score models are increasingly used in observational comparative effectiveness studies to reduce confounding by covariates that are associated with both a study outcome and treatment choice. Any such potentially confounding covariate will bias estimation of the effect of treatment on the outcome, unless the distribution of that covariate is well-balanced between treatment and control groups. Constructing a subsample of treated and control subjects who are matched on estimated propensity scores is a means of achieving such balance for covariates that are included in the propensity score model. If, during study design, investigators assemble a comprehensive inventory of known and suspected potentially confounding covariates, examination of how well this inventory is covered by the chosen dataset yields an assessment of the extent of bias reduction that is possible by matching on estimated propensity scores. These considerations are explored by examining the designs of three recently published comparative effectiveness studies.

How to Frame the Un-Known? The Odd Alliance of Design and "Fundamental Physics" in a Design School

ERIC Educational Resources Information Center

Gentes, Annie; Renon, Anne-Lyse; Bobroff, Julien

2017-01-01

This paper analyzes the introduction of fundamental physics in design education as a pedagogical method that trains designers to create with the un-known. It studies how three workshops offered design students to work on: superconductivity in 2011, quantum physics in 2013 and light and optics in 2014. The authors observe that introducing physics…

Performance comparison of attitude determination, attitude estimation, and nonlinear observers algorithms

NASA Astrophysics Data System (ADS)

MOHAMMED, M. A. SI; BOUSSADIA, H.; BELLAR, A.; ADNANE, A.

2017-01-01

This paper presents a brief synthesis and useful performance analysis of different attitude filtering algorithms (attitude determination algorithms, attitude estimation algorithms, and nonlinear observers) applied to Low Earth Orbit Satellite in terms of accuracy, convergence time, amount of memory, and computation time. This latter is calculated in two ways, using a personal computer and also using On-board computer 750 (OBC 750) that is being used in many SSTL Earth observation missions. The use of this comparative study could be an aided design tool to the designer to choose from an attitude determination or attitude estimation or attitude observer algorithms. The simulation results clearly indicate that the nonlinear Observer is the more logical choice.

Evaluation of horizontal curve design

DOT National Transportation Integrated Search

1980-08-01

This report documents an initial evaluation of horizontal curve design criteria which involved two phases: an observational study and an analytical evaluation. Three classes of vehicles (automobiles, school buses and tractor semi-trailers) and three ...

Traffic impacts of bicycle facilities : final report.

DOT National Transportation Integrated Search

2017-06-01

Engineers need information about interactions between vehicles and bicyclists to design efficient, safe transportation systems. This study involved a review of design guidelines for bicycle facilities, observation of bicycle-vehicle interactions at n...

Model Predictive Flight Control System with Full State Observer using H∞ Method

NASA Astrophysics Data System (ADS)

Sanwale, Jitu; Singh, Dhan Jeet

2018-03-01

This paper presents the application of the model predictive approach to design a flight control system (FCS) for longitudinal dynamics of a fixed wing aircraft. Longitudinal dynamics is derived for a conventional aircraft. Open loop aircraft response analysis is carried out. Simulation studies are illustrated to prove the efficacy of the proposed model predictive controller using H ∞ state observer. The estimation criterion used in the {H}_{∞} observer design is to minimize the worst possible effects of the modelling errors and additive noise on the parameter estimation.

Design Thinking for Life

ERIC Educational Resources Information Center

Watson, Andrew D.

2015-01-01

According to Vande Zande (2007), understanding the Design Process can help students become stronger critical thinkers. With this in mind, Andrew Watson decided to undertake an observational case study in which he focused directly on Design Thinking and addressed it more intentionally in his teaching. The hope was to understand how students saw…

Validation of an Instructional Observation Instrument for Teaching English as a Foreign Language in Spain

ERIC Educational Resources Information Center

Gomez-Garcia, Maria

2011-01-01

The design and validation of a classroom observation instrument to provide formative feedback for teachers of EFL in Spain is the overarching purpose of this study. This study proposes that a valid and reliable classroom observation instrument, based on effective practice in teaching EFL, can be developed and used in Spain to enable teachers to…

Providing Culturally Responsive Teaching in Field-Based and Student Teaching Experiences: A Case Study

ERIC Educational Resources Information Center

Kea, Cathy D.; Trent, Stanley C.

2013-01-01

This mixed design study chronicles the yearlong outcomes of 27 undergraduate preservice teacher candidates' ability to design and deliver culturally responsive lesson plans during field-based experience lesson observations and student teaching settings after receiving instruction in a special education methods course. While components of…

The equivalence of a human observer and an ideal observer in binary diagnostic tasks

NASA Astrophysics Data System (ADS)

He, Xin; Samuelson, Frank; Gallas, Brandon D.; Sahiner, Berkman; Myers, Kyle

2013-03-01

The Ideal Observer (IO) is "ideal" for given data populations. In the image perception process, as the raw images are degraded by factors such as display and eye optics, there is an equivalent IO (EIO). The EIO uses the statistical information that exits the perception/cognitive degradations as the data. We assume a human observer who received sufficient training, e.g., radiologists, and hypothesize that such a human observer can be modeled as if he is an EIO. To measure the likelihood ratio (LR) distributions of an EIO, we formalize experimental design principles that encourage rationality based on von Neumann and Morgenstern's (vNM) axioms. We present examples to show that many observer study design refinements, although motivated by empirical principles explicitly, implicitly encourage rationality. Our hypothesis is supported by a recent review paper on ROC curve convexity by Pesce, Metz, and Berbaum. We also provide additional evidence based on a collection of observer studies in medical imaging. EIO theory shows that the "sub-optimal" performance of a human observer can be mathematically formalized in the form of an IO, and measured through rationality encouragement.

Understanding Electrochemistry Concepts Using the Predict-Observe-Explain Strategy

ERIC Educational Resources Information Center

Karamustafaoglu, Sevilay; Mamlok-Naaman, Rachel

2015-01-01

The current study deals with freshman students who study at the Department of Science at the Faculty of Education. The aim of the study was to investigate the effect of teaching electrochemistry concepts using Predict-Observe-Explain (POE) strategy. The study was quasi-experimental design using 20 students each in the experimental group (EG) and…

Teaching the Poor in Turkey: A Phenomenological Insight

ERIC Educational Resources Information Center

Ömür, Yunus Emre

2018-01-01

The purpose of this study was to analyze how primary school classroom teachers experienced teaching poor students. This study was designed in a phenomenological approach. To fulfill the aim of the study, in-depth and focus group interviews were held as well as classroom observations. The data gathered through interviews and observations was…

Sulfonylureas and the Risks of Cardiovascular Events and Death: A Methodological Meta-Regression Analysis of the Observational Studies.

PubMed

Azoulay, Laurent; Suissa, Samy

2017-05-01

Recent randomized trials have compared the newer antidiabetic agents to treatments involving sulfonylureas, drugs associated with increased cardiovascular risks and mortality in some observational studies with conflicting results. We reviewed the methodology of these observational studies by searching MEDLINE from inception to December 2015 for all studies of the association between sulfonylureas and cardiovascular events or mortality. Each study was appraised with respect to the comparator, the outcome, and study design-related sources of bias. A meta-regression analysis was used to evaluate heterogeneity. A total of 19 studies were identified, of which six had no major design-related biases. Sulfonylureas were associated with an increased risk of cardiovascular events and mortality in five of these studies (relative risks 1.16-1.55). Overall, the 19 studies resulted in 36 relative risks as some studies assessed multiple outcomes or comparators. Of the 36 analyses, metformin was the comparator in 27 (75%) and death was the outcome in 24 (67%). The relative risk was higher by 13% when the comparator was metformin, by 20% when death was the outcome, and by 7% when the studies had design-related biases. The lowest predicted relative risk was for studies with no major bias, comparator other than metformin, and cardiovascular outcome (1.06 [95% CI 0.92-1.23]), whereas the highest was for studies with bias, metformin comparator, and mortality outcome (1.53 [95% CI 1.43-1.65]). In summary, sulfonylureas were associated with an increased risk of cardiovascular events and mortality in the majority of studies with no major design-related biases. Among studies with important biases, the association varied significantly with respect to the comparator, the outcome, and the type of bias. With the introduction of new antidiabetic drugs, the use of appropriate design and analytical tools will provide their more accurate cardiovascular safety assessment in the real-world setting. © 2017 by the American Diabetes Association.

Design and analysis of post-marketing research.

PubMed

Zhou, Xiao-Hua Andrew; Yang, Wei

2013-07-01

A post-marketing study is an integral part of research that helps to ensure a favorable risk-benefit profile for approved drugs used in the market. Because most of post-marketing studies use observational designs, which are liable to confounding, estimation of the causal effect of a drug versus a comparative one is very challenging. This article focuses on methodological issues of importance in designing and analyzing studies to evaluate the safety of marketed drugs, especially marketed traditional Chinese medicine (TCM) products. Advantages and limitations of the current designs and analytic methods for postmarketing studies are discussed, and recommendations are given for improving the validity of postmarketing studies in TCM products.

The Implementation and Evaluation of an Instructional Design Based on the Interdisciplinary Approach: Conscious Consumer Education

ERIC Educational Resources Information Center

Karakus, Memet; Uyar, Melis Yesilpinar

2018-01-01

The aim of this study was to implement and evaluate the instructional design prepared as consumer-oriented and based upon interdisciplinary curriculum. In this study, case study approach, which is one of the qualitative research patterns, was employed. Observations, interviews and document analysis were used to collect data. For analyzing the…

An observational examination of the literature in diagnostic anatomic pathology.

PubMed

Foucar, Elliott; Wick, Mark R

2005-05-01

Original research published in the medical literature confronts the reader with three very basic and closely linked questions--are the authors' conclusions true in the contextual setting in which the work was performed (internally valid); if so, are the conclusions also applicable in other practice settings (externally valid); and, if the conclusions of the study are bona fide, do they represent an important contribution to medical practice or are they true-but-insignificant? Most publications attempt to convince readers that the researchers' conclusions are both internally valid and important, and occasionally papers also directly address external validity. Developing standardized methods to facilitate the prospective determination of research importance would be useful to both journals and their readers, but has proven difficult. In contrast, the evidence-based medicine (EBM) movement has had more success with understanding and codifying factors thought to promote research validity. Of the many variables that can influence research validity, research design is the one that has received the most attention. The present paper reviews the contributions of EBM to understanding research validity, looking for areas where EBM's body of knowledge is applicable to the anatomic pathology (AP) literature. As part of this project, the authors performed a pilot observational analysis of a representative sample of the current pertinent literature on diagnostic tissue pathology. The results of that review showed that most of the latter publications employ one of the four categories of "observational" research design that have been delineated by the EBM movement, and that the most common of these observational designs is a "cross-sectional" comparison. Pathologists do not presently use the "experimental" research designs so admired by advocates of EBM. Slightly > 50% of AP observational studies employed statistical evaluations to support their final conclusions. Comparison of the current AP literature with a selected group of papers published in 1977 shows a discernible change over that period that has affected not just technological procedures, but also research design and use of statistics. Although we feel that advocates of EBM deserve credit for bringing attention to the close link between research design and research validity, much of the EBM effort has centered on refining "experimental" methodology, and the complexities of observational research have often been treated in an inappropriately dismissive manner. For advocates of EBM, an observational study is what you are relegated to as a second choice when you are unable to do an experimental study. The latter viewpoint may be true for evaluating new chemotherapeutic agents, but is unacceptable to pathologists, whose research advances are currently completely dependent on well-conducted observational research. Rather than succumb to randomization envy and accept EBM's assertion that observational research is second best, the challenge to AP is to develop and adhere to standards for observational research that will allow our patients to benefit from the full potential of this time tested approach to developing valid insights into disease.

Mathematical models used to inform study design or surveillance systems in infectious diseases: a systematic review.

PubMed

Herzog, Sereina A; Blaizot, Stéphanie; Hens, Niel

2017-12-18

Mathematical models offer the possibility to investigate the infectious disease dynamics over time and may help in informing design of studies. A systematic review was performed in order to determine to what extent mathematical models have been incorporated into the process of planning studies and hence inform study design for infectious diseases transmitted between humans and/or animals. We searched Ovid Medline and two trial registry platforms (Cochrane, WHO) using search terms related to infection, mathematical model, and study design from the earliest dates to October 2016. Eligible publications and registered trials included mathematical models (compartmental, individual-based, or Markov) which were described and used to inform the design of infectious disease studies. We extracted information about the investigated infection, population, model characteristics, and study design. We identified 28 unique publications but no registered trials. Focusing on compartmental and individual-based models we found 12 observational/surveillance studies and 11 clinical trials. Infections studied were equally animal and human infectious diseases for the observational/surveillance studies, while all but one between humans for clinical trials. The mathematical models were used to inform, amongst other things, the required sample size (n = 16), the statistical power (n = 9), the frequency at which samples should be taken (n = 6), and from whom (n = 6). Despite the fact that mathematical models have been advocated to be used at the planning stage of studies or surveillance systems, they are used scarcely. With only one exception, the publications described theoretical studies, hence, not being utilised in real studies.

Invited review: study design considerations for clinical research in veterinary radiology and radiation oncology.

PubMed

Scrivani, Peter V; Erb, Hollis N

2013-01-01

High quality clinical research is essential for advancing knowledge in the areas of veterinary radiology and radiation oncology. Types of clinical research studies may include experimental studies, method-comparison studies, and patient-based studies. Experimental studies explore issues relative to pathophysiology, patient safety, and treatment efficacy. Method-comparison studies evaluate agreement between techniques or between observers. Patient-based studies investigate naturally acquired disease and focus on questions asked in clinical practice that relate to individuals or populations (e.g., risk, accuracy, or prognosis). Careful preplanning and study design are essential in order to achieve valid results. A key point to planning studies is ensuring that the design is tailored to the study objectives. Good design includes a comprehensive literature review, asking suitable questions, selecting the proper sample population, collecting the appropriate data, performing the correct statistical analyses, and drawing conclusions supported by the available evidence. Most study designs are classified by whether they are experimental or observational, longitudinal or cross-sectional, and prospective or retrospective. Additional features (e.g., controlled, randomized, or blinded) may be described that address bias. Two related challenging aspects of study design are defining an important research question and selecting an appropriate sample population. The sample population should represent the target population as much as possible. Furthermore, when comparing groups, it is important that the groups are as alike to each other as possible except for the variables of interest. Medical images are well suited for clinical research because imaging signs are categorical or numerical variables that might be predictors or outcomes of diseases or treatments. © 2013 Veterinary Radiology & Ultrasound.

Implementation of a Bayesian design in a dose-escalation study of an experimental agent in healthy volunteers.

PubMed

Zhou, Yinghui; Whitehead, John; Korhonen, Pasi; Mustonen, Mika

2008-03-01

Bayesian decision procedures have recently been developed for dose escalation in phase I clinical trials concerning pharmacokinetic responses observed in healthy volunteers. This article describes how that general methodology was extended and evaluated for implementation in a specific phase I trial of a novel compound. At the time of writing, the study is ongoing, and it will be some time before the sponsor will wish to put the results into the public domain. This article is an account of how the study was designed in a way that should prove to be safe, accurate, and efficient whatever the true nature of the compound. The study involves the observation of two pharmacokinetic endpoints relating to the plasma concentration of the compound itself and of a metabolite as well as a safety endpoint relating to the occurrence of adverse events. Construction of the design and its evaluation via simulation are presented.

Meta-analyses including data from observational studies.

PubMed

O'Connor, Annette M; Sargeant, Jan M

2014-02-15

Observational studies represent a wide group of studies where the disease or condition of interest is naturally occurring and the investigator does not control allocation to interventions or exposures. Observational studies are used to test hypotheses about the efficacy of interventions or about exposure-disease relationships, to estimate incidence or prevalence of conditions, and to assess the sensitivity and specificity of diagnostic assays. Experimental-study designs and randomized controlled trials (RCTs) can also contribute to the body of evidence about such questions. Meta-analyses (either with or without systematic reviews) aim to combine information from primary research studies to better describe the entire body of work. The aim of meta-analyses may be to obtain a summary effect size, or to understand factors that affect effect sizes. In this paper, we discuss the role of observational studies in meta-analysis questions and some factors to consider when deciding whether a meta-analysis should include results from such studies. Our suggestion is that one should only include studies that are not at high risk of inherent bias when calculating a summary effect size. Study design however can be a meaningful variable in assessment of outcome heterogeneity. Copyright © 2013 Elsevier B.V. All rights reserved.

Misclassification of Case-Control Studies in Neurosurgery and Proposed Solutions.

PubMed

Esene, Ignatius Ngene; Mbuagbaw, Lawrence; Dechambenoit, Gilbert; Reda, Wael; Kalangu, Kazadi K

2018-04-01

Case-control studies (CCS) and cohort studies (CS) are common research designs in neurosurgery. But the term case-control study is frequently misused in the neurosurgical literature, with many articles reported as CCS, even although their methodology does not respect the basic components of a CCS. We sought to estimate the extent of these discrepancies in neurosurgical literature, explore factors contributing to mislabeling, and shed some light on study design reporting. We identified 31 top-ranking pure neurosurgical journals and searched them for articles reported as CCS, either in the title or in the abstract. The articles were read to determine if they really were CCS according to STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guidelines. Article assessment was conducted in duplicate (agreement [κ statistics] = 99.82%). Two hundred and twenty-four articles met our inclusion criteria, 133 of which (59.38%) correctly labeled the case-control design, whereas 91 (40.62%) misclassified this study design. Cohort studies (CS) were the most common design mislabeled as case-control studies in 76 articles (33.93%), 57 of which (25.45%) were retrospective CS. The mislabeling of CCS impairs the appropriate indexing, classification, and sorting of evidence. Mislabeling CS for CCS leads to a downgrading of evidence as CS represent the highest level of evidence for observational studies. Odds ratios instead of relative risk are reported for these studies, resulting in a distortion of the measurement of the effect size, compounded when these are summarized in systematic reviews and pooled in meta-analyses. Many studies reported as CCS are not true CCS. Reporting guidelines should include items that ensure that studies are labeled correctly. STROBE guidelines should be implemented in assessment of observational studies. Researchers in neurosurgery need better training in research methods and terminology. We also recommend accrued vigilance from reviewers and editors. Copyright © 2018 Elsevier Inc. All rights reserved.

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

Dolen, James; Harris, Philip; Marzani, Simone

Here, we explore the scale-dependence and correlations of jet substructure observables to improve upon existing techniques in the identification of highly Lorentz-boosted objects. Modified observables are designed to remove correlations from existing theoretically well-understood observables, providing practical advantages for experimental measurements and searches for new phenomena. We study such observables in W jet tagging and provide recommendations for observables based on considerations beyond signal and background efficiencies.

Preliminary design study of advanced multistage axial flow core compressors

NASA Technical Reports Server (NTRS)

Wisler, D. C.; Koch, C. C.; Smith, L. H., Jr.

1977-01-01

A preliminary design study was conducted to identify an advanced core compressor for use in new high-bypass-ratio turbofan engines to be introduced into commercial service in the 1980's. An evaluation of anticipated compressor and related component 1985 state-of-the-art technology was conducted. A parametric screening study covering a large number of compressor designs was conducted to determine the influence of the major compressor design features on efficiency, weight, cost, blade life, aircraft direct operating cost, and fuel usage. The trends observed in the parametric screening study were used to develop three high-efficiency, high-economic-payoff compressor designs. These three compressors were studied in greater detail to better evaluate their aerodynamic and mechanical feasibility.

Is gender still a predisposing factor in contrast-media associated adverse drug reactions? A systematic review and meta-analysis of randomized trials and observational studies.

PubMed

Lee, Heeyoung; Song, Seungyeon; Oh, Yun-Kyoung; Kang, WonKu; Kim, Eunyoung

2017-04-01

To evaluate the role of gender as a risk factor for developing contrast media-associated adverse drug reactions (CM-ADRs) by comparing the incidence of CM-ADR between male and female patients according to study design, ADR type, and computed tomography (CT) examination. We systematically searched three electronic databases for eligible studies. In the studies included (n=18), we assessed effect estimates of the relative incidence of CM-ADR, analysed by experimental design, ADR type and CT examination. This was calculated by using a random effects model if clinical conditions showed heterogeneity; otherwise, a fixed effects model was used. We identified 10,776 patients administered CM. According to the designs, studies were classified into randomised controlled trials (RCTs) and observational studies. Results were as follows: risk ratio (RR)=1.07 (95% confidence interval (CI): 0.79-1.46, P=0.66) for RCTs, and RR=0.77 (95% CI: 0.58-1.04, P=0.09) for observational studies. The results of analysis according to ADR type and for undergoing CT demonstrated that the incidence of CM-ADR did not differ between males and females. We found no significant difference in the incidence of CM-ADRs between male and female patients according to study design, ADR type, or CT examination. Future studies to determine why gender has shown different roles as a risk factor between CM-ADRs and non-CM ADRs are needed. Copyright © 2017 Elsevier B.V. All rights reserved.

Designing Health Websites Based on Users’ Web-Based Information-Seeking Behaviors: A Mixed-Method Observational Study

PubMed Central

Pang, Patrick Cheong-Iao; Verspoor, Karin; Pearce, Jon

2016-01-01

Background Laypeople increasingly use the Internet as a source of health information, but finding and discovering the right information remains problematic. These issues are partially due to the mismatch between the design of consumer health websites and the needs of health information seekers, particularly the lack of support for “exploring” health information. Objective The aim of this research was to create a design for consumer health websites by supporting different health information–seeking behaviors. We created a website called Better Health Explorer with the new design. Through the evaluation of this new design, we derive design implications for future implementations. Methods Better Health Explorer was designed using a user-centered approach. The design was implemented and assessed through a laboratory-based observational study. Participants tried to use Better Health Explorer and another live health website. Both websites contained the same content. A mixed-method approach was adopted to analyze multiple types of data collected in the experiment, including screen recordings, activity logs, Web browsing histories, and audiotaped interviews. Results Overall, 31 participants took part in the observational study. Our new design showed a positive result for improving the experience of health information seeking, by providing a wide range of information and an engaging environment. The results showed better knowledge acquisition, a higher number of page reads, and more query reformulations in both focused and exploratory search tasks. In addition, participants spent more time to discover health information with our design in exploratory search tasks, indicating higher engagement with the website. Finally, we identify 4 design considerations for designing consumer health websites and health information–seeking apps: (1) providing a dynamic information scope; (2) supporting serendipity; (3) considering trust implications; and (4) enhancing interactivity. Conclusions Better Health Explorer provides strong support for the heterogeneous and shifting behaviors of health information seekers and eases the health information–seeking process. Our findings show the importance of understanding different health information–seeking behaviors and highlight the implications for designers of consumer health websites and health information–seeking apps. PMID:27267955

Designing Health Websites Based on Users' Web-Based Information-Seeking Behaviors: A Mixed-Method Observational Study.

PubMed

Pang, Patrick Cheong-Iao; Chang, Shanton; Verspoor, Karin; Pearce, Jon

2016-06-06

Laypeople increasingly use the Internet as a source of health information, but finding and discovering the right information remains problematic. These issues are partially due to the mismatch between the design of consumer health websites and the needs of health information seekers, particularly the lack of support for "exploring" health information. The aim of this research was to create a design for consumer health websites by supporting different health information-seeking behaviors. We created a website called Better Health Explorer with the new design. Through the evaluation of this new design, we derive design implications for future implementations. Better Health Explorer was designed using a user-centered approach. The design was implemented and assessed through a laboratory-based observational study. Participants tried to use Better Health Explorer and another live health website. Both websites contained the same content. A mixed-method approach was adopted to analyze multiple types of data collected in the experiment, including screen recordings, activity logs, Web browsing histories, and audiotaped interviews. Overall, 31 participants took part in the observational study. Our new design showed a positive result for improving the experience of health information seeking, by providing a wide range of information and an engaging environment. The results showed better knowledge acquisition, a higher number of page reads, and more query reformulations in both focused and exploratory search tasks. In addition, participants spent more time to discover health information with our design in exploratory search tasks, indicating higher engagement with the website. Finally, we identify 4 design considerations for designing consumer health websites and health information-seeking apps: (1) providing a dynamic information scope; (2) supporting serendipity; (3) considering trust implications; and (4) enhancing interactivity. Better Health Explorer provides strong support for the heterogeneous and shifting behaviors of health information seekers and eases the health information-seeking process. Our findings show the importance of understanding different health information-seeking behaviors and highlight the implications for designers of consumer health websites and health information-seeking apps.

'Unconventional' experiments in biology and medicine with optimized design based on quantum-like correlations.

PubMed

Beauvais, Francis

2017-02-01

In previous articles, a description of 'unconventional' experiments (e.g. in vitro or clinical studies based on high dilutions, 'memory of water' or homeopathy) using quantum-like probability was proposed. Because the mathematical formulations of quantum logic are frequently an obstacle for physicians and biologists, a modified modeling that rests on classical probability is described in the present article. This modeling is inspired from a relational interpretation of quantum physics that applies not only to microscopic objects, but also to macroscopic structures, including experimental devices and observers. In this framework, any outcome of an experiment is not an absolute property of the observed system as usually considered but is expressed relatively to an observer. A team of interacting observers is thus described from an external view point based on two principles: the outcomes of experiments are expressed relatively to each observer and the observers agree on outcomes when they interact with each other. If probability fluctuations are also taken into account, correlations between 'expected' and observed outcomes emerge. Moreover, quantum-like correlations are predicted in experiments with local blind design but not with centralized blind design. No assumption on 'memory' or other physical modification of water is necessary in the present description although such hypotheses cannot be formally discarded. In conclusion, a simple modeling of 'unconventional' experiments based on classical probability is now available and its predictions can be tested. The underlying concepts are sufficiently intuitive to be spread into the homeopathy community and beyond. It is hoped that this modeling will encourage new studies with optimized designs for in vitro experiments and clinical trials. Copyright © 2017 The Faculty of Homeopathy. Published by Elsevier Ltd. All rights reserved.

A new iterative approach for multi-objective fault detection observer design and its application to a hypersonic vehicle

NASA Astrophysics Data System (ADS)

Huang, Di; Duan, Zhisheng

2018-03-01

This paper addresses the multi-objective fault detection observer design problems for a hypersonic vehicle. Owing to the fact that parameters' variations, modelling errors and disturbances are inevitable in practical situations, system uncertainty is considered in this study. By fully utilising the orthogonal space information of output matrix, some new understandings are proposed for the construction of Lyapunov matrix. Sufficient conditions for the existence of observers to guarantee the fault sensitivity and disturbance robustness in infinite frequency domain are presented. In order to further relax the conservativeness, slack matrices are introduced to fully decouple the observer gain with the Lyapunov matrices in finite frequency range. Iterative linear matrix inequality algorithms are proposed to obtain the solutions. The simulation examples which contain a Monte Carlo campaign illustrate that the new methods can effectively reduce the design conservativeness compared with the existing methods.

An Observational Study of Instructional and Curricular Practices Used with Gifted and Talented Students in Regular Classrooms. Research Monograph 93104.

ERIC Educational Resources Information Center

Westberg, Karen L.; And Others

This report describes one part of the Classroom Practices Study, focusing on systematic observations of gifted and talented students in 46 third and fourth grade classrooms. The observations were designed to determine if and how teachers meet the needs of gifted and talented students in regular classroom settings. The Classroom Practices Record…

Design of Urban Public Spaces: Intent vs. Reality

PubMed Central

Martin, W. Mike; Stewart, Tom; Troelsen, Jens

2018-01-01

This study investigated how two public spaces for sport and recreation were utilized by different user groups, and how this aligned with the initial design objectives for these spaces. Two newly built urban spaces situated in Copenhagen, Denmark, provided the context for this investigation. The System for Observing Play and Recreation in Communities (SOPARC) was used to examine the physical activity of users in these two urban spaces. The architects responsible for designing each space were interviewed to ascertain the intended target group of each space and to unravel the reasons behind the design decisions. The SOPARC observations revealed that males were more vigorously active than females when using the recreation facilities, and the observed users did not align with the intended target groups. The interviews suggested that design decisions were based on minimal interdisciplinary knowledge, and that expert knowledge was chosen randomly. These findings point to a systematic lack of evidence-based practice when designing sport and recreational facilities. This article has implications for landscape architects and urban planners; a new method must be developed to embed interdisciplinary knowledge in the planning process of future sport and recreation projects. This must be done in a systematic way to make the design process transparent. PMID:29690509

Lack of habituation to shocking words: the attentional bias to their spatial origin is context free.

PubMed

Bertels, Julie; Kolinsky, Régine; Morais, José

2012-01-01

Following a suggestion made by Aquino and Arnell (2007), we assumed that the processing of emotional words is influenced by their context of presentation. Supporting this idea, previous studies using the emotional Stroop task in its visual or auditory variant revealed different results depending on the mixed versus blocked presentation of the stimuli (Bertels, Kolinsky, Pietrons, & Morais, 2011; Richards, French, Johnson, Naparstek, & Williams, 1992). In the present study, we investigated the impact of these presentation designs on the occurrence of spatial attentional biases in a modified version of the beep-probe task (Bertels, Kolinsky, & Morais, 2010). Attentional vigilance to taboo words as well as non-spatial slowing effects of these words were observed whatever the mixed or blocked design, whereas attentional vigilance to positive words was only observed in the mixed design. Together with the results from our previous study (Bertels et al., 2010), the present data support the reliability of the effects of shocking stimuli, while vigilance to positive words would only be observed in a threatening context.

Project Orion: A Design Study of a System for Detecting Extrasolar Planets

NASA Technical Reports Server (NTRS)

Black, D. C. (Editor)

1980-01-01

A design concept for a ground based astrometric telescope that could significantly increase the potential accuracy of astrometric observations is considered. The state of current techniques and instrumentation is examined in the context of detecting extrasolar planets. Emphasis is placed on the direct detection of extrasolar planets at either visual or infrared wavelengths. The design concept of the imaging stellar interferometer (ISI), developed under Project Orion, is described. The Orion ISI employs the state-of-the-art technology and is theoretically capable of attaining 0.00010 arc sec/yr accuracy in relative astrometric observations.

Planned Missing Data Designs for Spline Growth Models in Salivary Cortisol Research

ERIC Educational Resources Information Center

Hogue, Candace M.; Pornprasertmanit, Sunthud; Fry, Mary D.; Rhemtulla, Mijke; Little, Todd D.

2013-01-01

Salivary cortisol is often used as an index of physiological and psychological stress in exercise science and psychoneuroendocrine research. A primary concern when designing research studies examining cortisol stems from the high cost of analysis. Planned missing data designs involve intentionally omitting a random subset of observations from data…

The Roles of Technical Communication Researchers in Design Scholarship

ERIC Educational Resources Information Center

Sánchez, Fernando

2017-01-01

Design has come to be understood as an essential aspect of the work that technical communicators claim. As a result, research in the field of technical communication has approached studies of design in numerous ways. This article showcases how technical communication researchers assume the roles of observers, testers, critics, creators, and…

Exploring Patient Activation in the Clinic: Measurement from Three Perspectives

ERIC Educational Resources Information Center

Ledford, Christy J. W.; Ledford, Christopher C.; Childress, Marc A.

2013-01-01

Objective. To further conceptualize and operationalize patient activation (PA), using measures from patient, physician, and researcher perspectives. Data Source/Study Setting. Multimethod observation in 2010 within a family medicine clinic. Study Design. Part of an intervention with 130 patients with type 2 diabetes, this observational study…

A Case Study on Teaching of Energy as a Subject for 9th Graders

ERIC Educational Resources Information Center

Bezen, Sevim; Bayrak, Celal; Aykutlu, Isil

2017-01-01

This study aims to describe how energy subject is taught in 9th grades. The study is designed as a descriptive case study with the participation of 3 physics teachers and 85 students. Data were obtained through observation, interviews, and documents, and they were analyzed through descriptive analysis method. In the observations made at the…

The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Statement: guidelines for reporting observational studies.

PubMed

von Elm, Erik; Altman, Douglas G; Egger, Matthias; Pocock, Stuart J; Gøtzsche, Peter C; Vandenbroucke, Jan P

2014-12-01

Much biomedical research is observational. The reporting of such research is often inadequate, which hampers the assessment of its strengths and weaknesses and of a study's generalisability. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) Initiative developed recommendations on what should be included in an accurate and complete report of an observational study. We defined the scope of the recommendations to cover three main study designs: cohort, case-control, and cross-sectional studies. We convened a 2-day workshop in September 2004, with methodologists, researchers, and journal editors to draft a checklist of items. This list was subsequently revised during several meetings of the coordinating group and in e-mail discussions with the larger group of STROBE contributors, taking into account empirical evidence and methodological considerations. The workshop and the subsequent iterative process of consultation and revision resulted in a checklist of 22 items (the STROBE Statement) that relate to the title, abstract, introduction, methods, results, and discussion sections of articles. 18 items are common to all three study designs and four are specific for cohort, case-control, or cross-sectional studies. A detailed Explanation and Elaboration document is published separately and is freely available on the Web sites of PLoS Medicine, Annals of Internal Medicine, and Epidemiology. We hope that the STROBE Statement will contribute to improving the quality of reporting of observational studies. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

The response of single human cells to zero gravity

NASA Technical Reports Server (NTRS)

Montgomery, P. O., Jr.; Cook, J. E.; Reynolds, R. C.; Paul, J. S.; Hayflick, L.; Stock, D.; Schulz, W. W.; Kimzey, S. L.; Thirolf, R. G.; Rogers, T.

1974-01-01

The SO15 experiment was designed to extend observations of the effects of zero-gravity to living human cells during and subsequent to a 59-day flight on Skylab 3. A strain of diploid human embryonic lung cells, WI-38, was chosen for this purpose. The studies were concerned with observations designed to detect the effects of zero-gravity on cell growth rates and on cell structure as observed by light microscopy, transmission and scanning electron microscopy and histochemistry. Studies of the effects of zero-gravity on the cell function and the cell cycle were performed by time lapse motion picture photography and microspectrophotometry. Subsequent study of the returned living cells included karotyping, G- and C-banding, and analyses of the culture media used. Some of the living cells returned were banked by deep freeze techniques for possible future experiments.

Rationale and design of the vitamin D and type 2 diabetes (D2d) study: a diabetes prevention trial

USDA-ARS?s Scientific Manuscript database

OBJECTIVE: Observational studies suggest that vitamin D may lower the risk of type 2 diabetes. However, data from long-term trials are lacking. The Vitamin D and Type 2 Diabetes (D2d) study is a randomized clinical trial designed to examine whether a causal relationship exists between vitamin D supp...

Observations of hydrogen-rich supernovae in the first days after explosion and new instruments to study them

NASA Astrophysics Data System (ADS)

Rubin, Adam; PTF

2018-01-01

I will discuss our results studying light curves of hydrogen-rich supernovae during the first few days after explosion. The first days of emission encode important information about the physical system, and it is possible to relate the early-time light curve to the radius of the progenitor star by using shock-cooling models. I will show the first systematic application of these models to data from the Palomar Transient Factory (PTF). We found that R-band data alone at PTF cadence cannot constrain the radius but can constrain the energy per unit mass of the explosion, uncovering new correlations with other supernova observables. We constrained the radii for events with multi-wavelength observations, and for two events observed with the Kepler mission at 30 min cadence. I will discuss improved observing strategies to obtain more constraining results in the future. Some tensions have arisen between our results and the expected radii from identified progenitors of hydrogen-rich supernovae. The resolution of these tensions may be related to the effect of circumstellar material on the light curves, motivating future systematic spectroscopic sequencing of these events. To this end, we have designed a new medium resolution UV-VIS spectrograph. The Multi-Imaging Transient Spectrograph (MITS) is the R~4500 UV-VIS arm of the Son Of X-Shooter (SOXS) spectrograph proposed for ESO’s 3.6 m New Technology Telescope. Our design divides the spectrum into several sub-bands, allowing optimization for each narrow part of the spectrum. We estimate a 50-100% improvement in throughput relative to a classical 4-C echelle design. Our design has passed a preliminary design review and is expected on the telescope in early 2021.

The Power and Pitfalls of Big Data Research in Obstetrics and Gynecology: A Consumer's Guide

PubMed Central

Goodin, Amie; Delcher, Chris; Valenzuela, Chelsea; Wang, Xi; Zhu, Yanmin; Roussos-Ross, Dikea; Brown, Joshua D.

2017-01-01

Importance Research in obstetrics and gynecology (OB/GYN) increasingly relies on “big data” and observational study designs. There is a gap in practitioner-relevant guides to interpret and critique such research. Objective This guide is an introduction to interpreting research using observational data and provides explanations and context for related terminology. In addition, it serves as a guide for critiquing OB/GYN studies that use observational data by outlining how to assess common pitfalls of experimental and observational study designs. Lastly, the piece provides a compendium of observational data resources commonly used within OB/GYN research. Evidence Acquisition Review of literature was conducted for the collection of definitions and examples of terminology related to observational data research. Data resources were collected via Web search and researcher recommendations. Next, each data resource was reviewed and analyzed for content and accessibility. Contents of data resources were organized into summary tables and matched to relevant literature examples. Results We identified 26 observational data resources frequently used in secondary analysis for OB/GYN research. Cost, accessibility considerations for software/hardware capabilities, and contents of each data resource varied substantially. Conclusions and Relevance Observational data sources can provide researchers with a variety of options in tackling their research questions related to OB/GYN practice, patient health outcomes, trends in utilization of medications/procedures, or prevalence estimates of disease states. Insurance claims data resources are useful for population-level prevalence estimates and utilization trends, whereas electronic health record–derived data and patient survey data may be more useful for exploring patient behaviors and trends in practice. Target Audience Obstetricians and gynecologists, family physicians. Learning Objectives After completing this activity, the learner should be better able to identify and define terminology used in observational data research; compare the features, strengths, and limitations of observational study designs and randomized controlled trials; distinguish between types of observational data (eg, insurance administrative claims, discharges, electronic health record databases, surveys, surveillance data) and weigh the strengths and limitations of research that uses each data type; interpret and critique OB/GYN research that uses observational data and secondary data analysis; and gain exposure and familiarity with a selection of observational data sets used to study topics relevant to obstetrical and gynecological practice and/or health outcomes. PMID:29164265

Characterizing Mathematics Classroom Practice: Impact of Observation and Coding Choices

ERIC Educational Resources Information Center

Ing, Marsha; Webb, Noreen M.

2012-01-01

Large-scale observational measures of classroom practice increasingly focus on opportunities for student participation as an indicator of instructional quality. Each observational measure necessitates making design and coding choices on how to best measure student participation. This study investigated variations of coding approaches that may be…

Validating an Observation Protocol to Measure Special Education Teacher Effectiveness

ERIC Educational Resources Information Center

Johnson, Evelyn S.; Semmelroth, Carrie L.

2015-01-01

This study used Kane's (2013) Interpretation/Use Argument (IUA) to measure validity on the Recognizing Effective Special Education Teachers (RESET) observation tool. The RESET observation tool is designed to evaluate special education teacher effectiveness using evidence-based instructional practices as the basis for evaluation. In alignment with…

Making intelligent systems team players: Additional case studies

NASA Technical Reports Server (NTRS)

Malin, Jane T.; Schreckenghost, Debra L.; Rhoads, Ron W.

1993-01-01

Observations from a case study of intelligent systems are reported as part of a multi-year interdisciplinary effort to provide guidance and assistance for designers of intelligent systems and their user interfaces. A series of studies were conducted to investigate issues in designing intelligent fault management systems in aerospace applications for effective human-computer interaction. The results of the initial study are documented in two NASA technical memoranda: TM 104738 Making Intelligent Systems Team Players: Case Studies and Design Issues, Volumes 1 and 2; and TM 104751, Making Intelligent Systems Team Players: Overview for Designers. The objective of this additional study was to broaden the investigation of human-computer interaction design issues beyond the focus on monitoring and fault detection in the initial study. The results of this second study are documented which is intended as a supplement to the original design guidance documents. These results should be of interest to designers of intelligent systems for use in real-time operations, and to researchers in the areas of human-computer interaction and artificial intelligence.

Bovine thrombin safety reporting: an example of study design and publication bias.

PubMed

Crean, Sheila; Michels, Shannon L; Moschella, Kevin; Reynolds, Matthew W

2010-01-01

Bovine thrombin, a popular hemostat and sealant since 1945, has recently been subjected to clinical trial testing due to reformulations in 1998. We sought to compare adverse event rates of early observational studies with those of later interventional trials. A MEDLINE-based literature search in publications that report safety in bovine thrombin exposed surgical patients was extracted and reviewed. In 38 studies, about half were case reports and 31.5% were interventional trials. In case reports, 41% of authors reported severe coagulopathic adverse events. In contrast, whereas blood complications were common in large trials, no association of harm was established for bovine thrombin product exposure and/or immunization. In this review, later clinical trials failed to reproduce the common and severe coagulopathy predicted by earlier observational studies in bovine exposed patients. This example illustrates that perceptions of safety can change as a function of study design, even for a widely adopted, well established biologic such as thrombin. Caution must be exercised in interpreting evidence from observational studies alone.

Observer-Based Discrete-Time Nonnegative Edge Synchronization of Networked Systems.

PubMed

Su, Housheng; Wu, Han; Chen, Xia

2017-10-01

This paper studies the multi-input and multi-output discrete-time nonnegative edge synchronization of networked systems based on neighbors' output information. The communication relationship among the edges of networked systems is modeled by well-known line graph. Two observer-based edge synchronization algorithms are designed, for which some necessary and sufficient synchronization conditions are derived. Moreover, some computable sufficient synchronization conditions are obtained, in which the feedback matrix and the observer matrix are computed by solving the linear programming problems. We finally design several simulation examples to demonstrate the validity of the given nonnegative edge synchronization algorithms.

Personalized ovarian stimulation for assisted reproductive technology: study design considerations to move from hype to added value for patients.

PubMed

Mol, Ben W; Bossuyt, Patrick M; Sunkara, Sesh K; Garcia Velasco, Juan A; Venetis, Christos; Sakkas, Denny; Lundin, Kersti; Simón, Carlos; Taylor, Hugh S; Wan, Robert; Longobardi, Salvatore; Cottell, Evelyn; D'Hooghe, Thomas

2018-06-01

Although most medical treatments are designed for the average patient with a one-size-fits-all-approach, they may not benefit all. Better understanding of the function of genes, proteins, and metabolite, and of personal and environmental factors has led to a call for personalized medicine. Personalized reproductive medicine is still in its infancy, without clear guidance on treatment aspects that could be personalized and on trial design to evaluate personalized treatment effect and benefit-harm balance. While the rationale for a personalized approach often relies on retrospective analyses of large observational studies or real-world data, solid evidence of superiority of a personalized approach will come from randomized trials comparing outcomes and safety between a personalized and one-size-fits-all strategy. A more efficient, targeted randomized trial design may recruit only patients or couples for which the personalized approach would differ from the previous, standard approach. Multiple monocenter studies using the same study protocol (allowing future meta-analysis) might reduce the major center effect associated with multicenter studies. In certain cases, single-arm observational studies can generate the necessary evidence for a personalized approach. This review describes each of the main segments of patient care in assisted reproductive technologies treatment, addressing which aspects could be personalized, emphasizing current evidence and relevant study design. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Accessible maps for the color vision deficient observers: past and present knowledge and future possibilities

NASA Astrophysics Data System (ADS)

Kvitle, Anne Kristin

2018-05-01

Color is part of the visual variables in map, serving an aesthetic part and as a guide of attention. Impaired color vision affects the ability to distinguish colors, which makes the task of decoding the map colors difficult. Map reading is reported as a challenging task for these observers, especially when the size of stimuli is small. The aim of this study is to review existing methods for map design for color vision deficient users. A systematic review of research literature and case studies of map design for CVD observers has been conducted in order to give an overview of current knowledge and future research challenges. In addition, relevant research on simulations of CVD and color image enhancement for these observers from other fields of industry is included. The study identified two main approaches: pre-processing by using accessible colors and post-processing by using enhancement methods. Some of the methods may be applied for maps, but requires tailoring of test images according to map types.

Antioxidants and cancer therapy: a systematic review.

PubMed

Ladas, Elena J; Jacobson, Judith S; Kennedy, Deborah D; Teel, Katherine; Fleischauer, Aaron; Kelly, Kara M

2004-02-01

Many patients with cancer take antioxidant nutritional supplements during cancer treatment to alleviate treatment toxicities and to improve long-term outcomes, but little is known about the efficacy and safety of antioxidant use during cancer treatment. We reviewed English-language manuscripts published in the biomedical literature, reporting the results of observational studies of antioxidant status and cancer outcomes and of intervention trials of antioxidants among patients receiving chemotherapy with or without radiation for various malignancies. We searched the Medline database and the bibliographies of the retrieved manuscripts, reviews, and books on antioxidants and cancer. The retrieved studies are grouped by study design, malignancy, and end points. More than 100 citations were retrieved; 52 met our criteria, 31 were observational studies, and 21 were intervention trials. The studies varied in study design, timing of observation/intervention, intervention protocol, malignancy, and anticancer regimen. These inconsistencies preclude a definitive conclusion as to the effect of chemotherapy on antioxidant status in patients undergoing anticancer therapy. However, our review suggests that total antioxidant status (measured by total radical antioxidant parameter) declines during cancer treatment. Adequately powered trials or observational studies among patients with a specific cancer diagnosis receiving a specific treatment regimen are needed to address patients' and physicians' concerns regarding these associations.

The AQUA-FONTIS study: protocol of a multidisciplinary, cross-sectional and prospective longitudinal study for developing standardized diagnostics and classification of non-thyroidal illness syndrome

PubMed Central

Dietrich, Johannes W; Stachon, Axel; Antic, Biljana; Klein, Harald H; Hering, Steffen

2008-01-01

Background Non-thyroidal illness syndrome (NTIS) is a characteristic functional constellation of thyrotropic feedback control that frequently occurs in critically ill patients. Although this condition is associated with significantly increased morbidity and mortality, there is still controversy on whether NTIS is caused by artefacts, is a form of beneficial adaptation, or is a disorder requiring treatment. Trials investigating substitution therapy of NTIS revealed contradictory results. The comparison of heterogeneous patient cohorts may be the cause for those inconsistencies. Objectives Primary objective of this study is the identification and differentiation of different functional states of thyrotropic feedback control in order to define relevant evaluation criteria for the prognosis of affected patients. Furthermore, we intend to assess the significance of an innovative physiological index approach (SPINA) in differential diagnosis between NTIS and latent (so-called "sub-clinical") thyrotoxicosis. Secondary objective is observation of variables that quantify distinct components of NTIS in the context of independent predictors of evolution, survival or pathophysiological condition and influencing or disturbing factors like medication. Design The approach to a quantitative follow-up of non-thyroidal illness syndrome (AQUA FONTIS study) is designed as both a cross-sectional and prospective longitudinal observation trial in critically ill patients. Patients are observed in at least two evaluation points with consecutive assessments of thyroid status, physiological and clinical data in additional weekly observations up to discharge. A second part of the study investigates the neuropsychological impact of NTIS and medium-term outcomes. The study design incorporates a two-module structure that covers a reduced protocol in form of an observation trial before patients give informed consent. Additional investigations are performed if and after patients agree in participation. Trial Registration ClinicalTrials.gov NCT00591032 PMID:18851740

Portfolio: a prototype workstation for development and evaluation of tools for analysis and management of digital portal images.

PubMed

Boxwala, A A; Chaney, E L; Fritsch, D S; Friedman, C P; Rosenman, J G

1998-09-01

The purpose of this investigation was to design and implement a prototype physician workstation, called PortFolio, as a platform for developing and evaluating, by means of controlled observer studies, user interfaces and interactive tools for analyzing and managing digital portal images. The first observer study was designed to measure physician acceptance of workstation technology, as an alternative to a view box, for inspection and analysis of portal images for detection of treatment setup errors. The observer study was conducted in a controlled experimental setting to evaluate physician acceptance of the prototype workstation technology exemplified by PortFolio. PortFolio incorporates a windows user interface, a compact kit of carefully selected image analysis tools, and an object-oriented data base infrastructure. The kit evaluated in the observer study included tools for contrast enhancement, registration, and multimodal image visualization. Acceptance was measured in the context of performing portal image analysis in a structured protocol designed to simulate clinical practice. The acceptability and usage patterns were measured from semistructured questionnaires and logs of user interactions. Radiation oncologists, the subjects for this study, perceived the tools in PortFolio to be acceptable clinical aids. Concerns were expressed regarding user efficiency, particularly with respect to the image registration tools. The results of our observer study indicate that workstation technology is acceptable to radiation oncologists as an alternative to a view box for clinical detection of setup errors from digital portal images. Improvements in implementation, including more tools and a greater degree of automation in the image analysis tasks, are needed to make PortFolio more clinically practical.

Multiple case studies of STEM teachers' orientations to science teaching through engineering design

NASA Astrophysics Data System (ADS)

Rupp, Madeline

The following master's thesis is composed of two manuscripts describing STEM teachers' orientations to science teaching through engineering within the context of the Science Learning through Engineering Design (SLED) partnership. The framework guiding both studies was science teaching orientations, a component of pedagogical content knowledge. Data were collected via semi-structured interviews, multi-day classroom observations, pre- and post-observation interviews, implementation plans, and written reflections. Data sources were analyzed to generate two orientations to science teaching through engineering design for each participant. The first manuscript illustrates a single case study conducted with a sixth grade STEM teacher. Results of this study revealed a detailed picture of the teacher's goals, practices, assessments, and general views when teaching science through engineering design. Common themes across the teacher's instruction were used to characterize her orientations to science teaching through engineering design. Overall, the teacher's orientations showed a shift in her practice from didactic to student-centered methods of teaching as a result of integrating engineering design-based curriculum. The second manuscript describes a comparative case study of two sixth grade SLED participants. Results of this study revealed more complex and diverse relationships between the teachers' orientations to teaching science through engineering design and their instruction. Participants' orientations served as filters for instruction, guided by their divergent purposes for science teaching. Furthermore, their orientations and resulting implementation were developed from knowledge gained in teacher education, implying that teacher educators and researchers can use this framework to learn more about how teachers' knowledge is used to integrate engineering and science practices in the K-12 classroom.

Using observed postconstruction peak discharges to evaluate a hydrologic and hydraulic design model, Boneyard Creek, Champaign and Urbana, Illinois

USGS Publications Warehouse

Over, Thomas M.; Soong, David T.; Holmes, Robert R.

2011-01-01

Boneyard Creek—which drains an urbanized watershed in the cities of Champaign and Urbana, Illinois, including part of the University of Illinois at Urbana-Champaign (UIUC) campus—has historically been prone to flooding. Using the Stormwater Management Model (SWMM), a hydrologic and hydraulic model of Boneyard Creek was developed for the design of the projects making up the first phase of a long-term plan for flood control on Boneyard Creek, and the construction of the projects was completed in May 2003. The U.S. Geological Survey, in cooperation with the Cities of Champaign and Urbana and UIUC, installed and operated stream and rain gages in order to obtain data for evaluation of the design-model simulations. In this study, design-model simulations were evaluated by using observed postconstruction precipitation and peak-discharge data. Between May 2003 and September 2008, five high-flow events on Boneyard Creek satisfied the study criterion. The five events were simulated with the design model by using observed precipitation. The simulations were run with two different values of the parameter controlling the soil moisture at the beginning of the storms and two different ways of spatially distributing the precipitation, making a total of four simulation scenarios. The simulated and observed peak discharges and stages were compared at gaged locations along the Creek. The discharge at one of these locations was deemed to be critical for evaluating the design model. The uncertainty of the measured peak discharge was also estimated at the critical location with a method based on linear regression of the stage and discharge relation, an estimate of the uncertainty of the acoustic Doppler velocity meter measurements, and the uncertainty of the stage measurements. For four of the five events, the simulated peak discharges lie within the 95-percent confidence interval of the observed peak discharges at the critical location; the fifth was just outside the upper end of this interval. For two of the four simulation scenarios, the simulation results for one event at the critical location were numerically unstable in the vicinity of the discharge peak. For the remaining scenarios, the simulated peak discharges over the five events at the critical location differ from the observed peak discharges (simulated minus observed) by an average of 7.7 and -1.5 percent, respectively. The simulated peak discharges over the four events for which all scenarios have numerically stable results at the critical location differs from the observed peak discharges (simulated minus observed) by an average of -6.8, 4.0, -5.4, and 1.5 percent, for the four scenarios, respectively. Overall, the discharge peaks simulated for this study at the critical location are approximately balanced between overprediction and underprediction and do not indicate significant model bias or inaccuracy. Additional comparisons were made by using peak stages at the critical location and two additional sites and using peak discharges at one additional site. These comparisons showed the same pattern of differences between observed and simulated values across events but varying biases depending on streamgage and measurement type (discharge or stage). Altogether, the results from this study show no clear evidence that the design model is significantly inaccurate or biased and, therefore, no clear evidence that the modeled flood-control projects in Champaign and on the University of Illinois campus have increased flood stages or discharges downstream in Urbana.

Load Transfer Characteristics of Various Designs of Three-Implant-Retained Mandibular Overdentures.

PubMed

Tokar, Emre; Uludag, Bulent

2015-01-01

Many different attachment systems (eg, bars, studs, magnets, telescopic copings) have been used to retain overdentures. The current study aimed to investigate the load transfer characteristics and to compare the stress levels of four attachment designs for mandibular overdentures retained by one central implant and two inclined distal implants. Photoelastic mandibular models fabricated with three screw-type implants (Tapered Screw-Vent, 3.75 × 13 mm) were placed in the parasymphyseal area. The center implant was vertically oriented to the midline, and the other implants were embedded in the canine areas with a 20-degree angulation relative to the center implant. Four overdentures with different attachment designs (bar, bar/ball, bar/distally placed Rk-1s, and Locators) were studied in the context of this model. Vertical loads (100 N) were applied to the central fossa of the right first molar area of each overdenture. Stress levels that developed in the denture-bearing areas and around the implants were observed photoelastically and evaluated visually. The studied attachment designs showed low and moderate stress levels. The greatest stress was found with the bar/ball design, while the lowest stress levels were observed with the Locator attachment design. Stresses were concentrated on the loaded side for each design. All tested designs experienced moderate stress around the posterior edentulous area. None of the designs experienced more than moderate stress. The lowest stress was noted with the Locator attachments, which transmitted little discernible stress around the implants.

The WFIRST Interim Design Reference Mission: Capabilities, Constraints, and Open Questions

NASA Technical Reports Server (NTRS)

Kruk, Jeffrey W.

2012-01-01

The Project Office and Science Definition Team for the Wide-Field Infrared Survey Telescope (WFIRST) are in the midst of a pre-Phase A study to establish a Design Reference Mission (DRM). An Interim report was released in June 2011, with a final report due later in 2012. The predicted performance of the Interim DRM Observatory will be described, including optical quality, observing efficiency, and sensitivity for representative observing scenarios. Observing constraints and other limitations on performance will also be presented, with an emphasis on potential Guest Observer programs. Finally, a brief status update will be provided on open trade studies of interest to the scientific community. The final DRM may differ from the Interim DRM presented here. However, the underlying requirements of the scientific programs are not expected to change, hence the capabilities of the IDRM are likely to be maintained even if the implementation changes in significant ways.

The empowerment of sustainable design in food packaging as designer responsibilities

NASA Astrophysics Data System (ADS)

Setiadi, V.

2018-01-01

The purpose of this paper is emphasized on the empowerment of sustainable design in providing the dual function of a food packaging. Which can extend the life of paper, cardboard, plastic, aluminum foil so as to reduce the contribution of waste on earth. The methodology used in this research is using qualitative research. With the main approach taken on the layout of the packaging design, the approach that relies heavily on the data in the form of packaging design. For the process of observation, the authors should compare with the forms of food packaging designs that are contained in the diversity of food packaging types from products outside Indonesia. The purpose of this study is also intended as a recommendation through observation of data interviews and survey related products. Conclusion through material exploration, packaging structure exploration, efficient exploration of ink usage and packaging usage patterns.

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

PubMed

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

2016-05-01

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

Estimating open population site occupancy from presence-absence data lacking the robust design.

PubMed

Dail, D; Madsen, L

2013-03-01

Many animal monitoring studies seek to estimate the proportion of a study area occupied by a target population. The study area is divided into spatially distinct sites where the detected presence or absence of the population is recorded, and this is repeated in time for multiple seasons. However, when occupied sites are detected with probability p < 1, the lack of a detection does not imply lack of occupancy. MacKenzie et al. (2003, Ecology 84, 2200-2207) developed a multiseason model for estimating seasonal site occupancy (ψt ) while accounting for unknown p. Their model performs well when observations are collected according to the robust design, where multiple sampling occasions occur during each season; the repeated sampling aids in the estimation p. However, their model does not perform as well when the robust design is lacking. In this paper, we propose an alternative likelihood model that yields improved seasonal estimates of p and Ψt in the absence of the robust design. We construct the marginal likelihood of the observed data by conditioning on, and summing out, the latent number of occupied sites during each season. A simulation study shows that in cases without the robust design, the proposed model estimates p with less bias than the MacKenzie et al. model and hence improves the estimates of Ψt . We apply both models to a data set consisting of repeated presence-absence observations of American robins (Turdus migratorius) with yearly survey periods. The two models are compared to a third estimator available when the repeated counts (from the same study) are considered, with the proposed model yielding estimates of Ψt closest to estimates from the point count model. Copyright © 2013, The International Biometric Society.

Amateur boxing and risk of chronic traumatic brain injury: systematic review of observational studies

PubMed Central

Knowles, Charles H; Whyte, Greg P

2007-01-01

Objective To evaluate the risk of chronic traumatic brain injury from amateur boxing. Setting Secondary research performed by combination of sport physicians and clinical academics. Design, data sources, and methods Systematic review of observational studies in which chronic traumatic brain injury was defined as any abnormality on clinical neurological examination, psychometric testing, neuroimaging studies, and electroencephalography. Studies were identified through database (1950 to date) and bibliographic searches without language restrictions. Two reviewers extracted study characteristics, quality, and data, with adherence to a protocol developed from a widely recommended method for systematic review of observational studies (MOOSE). Results 36 papers had relevant extractable data (from a detailed evaluation of 93 studies of 943 identified from the initial search). Quality of evidence was generally poor. The best quality studies were those with a cohort design and those that used psychometric tests. These yielded the most negative results: only four of 17 (24%) better quality studies found any indication of chronic traumatic brain injury in a minority of boxers studied. Conclusion There is no strong evidence to associate chronic traumatic brain injury with amateur boxing. PMID:17916811

Amateur boxing and risk of chronic traumatic brain injury: systematic review of observational studies.

PubMed

Loosemore, Mike; Knowles, Charles H; Whyte, Greg P

2007-10-20

To evaluate the risk of chronic traumatic brain injury from amateur boxing. Secondary research performed by combination of sport physicians and clinical academics. DESIGN, DATA SOURCES, AND METHODS: Systematic review of observational studies in which chronic traumatic brain injury was defined as any abnormality on clinical neurological examination, psychometric testing, neuroimaging studies, and electroencephalography. Studies were identified through database (1950 to date) and bibliographic searches without language restrictions. Two reviewers extracted study characteristics, quality, and data, with adherence to a protocol developed from a widely recommended method for systematic review of observational studies (MOOSE). 36 papers had relevant extractable data (from a detailed evaluation of 93 studies of 943 identified from the initial search). Quality of evidence was generally poor. The best quality studies were those with a cohort design and those that used psychometric tests. These yielded the most negative results: only four of 17 (24%) better quality studies found any indication of chronic traumatic brain injury in a minority of boxers studied. There is no strong evidence to associate chronic traumatic brain injury with amateur boxing.

Risk of bias and confounding of observational studies of Zika virus infection: A scoping review of research protocols.

PubMed

Reveiz, Ludovic; Haby, Michelle M; Martínez-Vega, Ruth; Pinzón-Flores, Carlos E; Elias, Vanessa; Smith, Emma; Pinart, Mariona; Broutet, Nathalie; Becerra-Posada, Francisco; Aldighieri, Sylvain; Van Kerkhove, Maria D

2017-01-01

Given the severity and impact of the current Zika virus (ZIKV) outbreak in the Americas, numerous countries have rushed to develop research studies to assess ZIKV and its potential health consequences. In an effort to ensure that studies are comprehensive, both internally and externally valid, and with reliable results, the World Health Organization, the Pan American Health Organization, Institut Pasteur, the networks of Fiocruz, the Consortia for the Standardization of Influenza Seroepidemiology (CONSISE) and the International Severe Acute Respiratory and Emerging Infection Consortium (ISARIC) have generated six standardized clinical and epidemiological research protocols and questionnaires to address key public health questions on ZIKV. We conducted a systematic search of ongoing study protocols related to ZIKV research. We analyzed the content of protocols of 32 cohort studies and 13 case control studies for systematic bias that could produce erroneous results. Additionally we aimed to characterize the risks of bias and confounding in observational studies related to ZIKV and to propose ways to minimize them, including the use of six newly standardized research protocols. Observational studies of ZIKV face an array of challenges, including measurement of exposure and outcomes (microcephaly and Guillain-Barré Syndrome). Potential confounders need to be measured where known and controlled for in the analysis. Selection bias due to non-random selection is a significant issue, particularly in the case-control design, and losses to follow-up is equally important for the cohort design. Observational research seeking to answer key questions on the ZIKV should consider these restrictions and take precautions to minimize bias in an effort to provide reliable and valid results. Utilization of the standardized research protocols developed by the WHO, PAHO, Institut Pasteur, and CONSISE will harmonize the key methodological aspects of each study design to minimize bias at different stages of the study. Biases need to be considered by researchers implementing the standardized protocols as well as by users of observational epidemiological studies of ZIKV.

A versatile substrate design for LEED and AES studies in uhv.

NASA Technical Reports Server (NTRS)

Holloway, P. H.; Hudson, J. B.

1972-01-01

A substrate design is described that incorporates a single crystal disk into an electrically isolated, electron bombardment heated mount. Electron and photon leakage from the bombarding filament are prevented, and LEED and AES may be used at elevated temperatures. A cold finger, thermally coupled to the mount, decreases the time lost between cleaning the crystal and cooling it to the desired observation temperature. The cold finger also allows observation at temperatures below ambient.

Observer-Based Non-PDC Control for Networked T-S Fuzzy Systems With an Event-Triggered Communication.

PubMed

Peng, Chen; Ma, Shaodong; Xie, Xiangpeng

2017-02-07

This paper addresses the problem of an event-triggered non-parallel distribution compensation (PDC) control for networked Takagi-Sugeno (T-S) fuzzy systems, under consideration of the limited data transmission bandwidth and the imperfect premise matching membership functions. First, a unified event-triggered T-S fuzzy model is provided, in which: 1) a fuzzy observer with the imperfect premise matching is constructed to estimate the unmeasurable states of the studied system; 2) a fuzzy controller is designed following the same premise as the observer; and 3) an output-based event-triggering transmission scheme is designed to economize the restricted network resources. Different from the traditional PDC method, the synchronous premise between the fuzzy observer and the T-S fuzzy system are no longer needed in this paper. Second, by use of Lyapunov theory, a stability criterion and a stabilization condition are obtained for ensuring asymptotically stable of the studied system. On account of the imperfect premise matching conditions are well considered in the derivation of the above criteria, less conservation can be expected to enhance the design flexibility. Compared with some existing emulation-based methods, the controller gains are no longer required to be known a priori. Finally, the availability of proposed non-PDC design scheme is illustrated by the backing-up control of a truck-trailer system.

Project-Based Learning in Engineering Design in Bulgaria: Expectations, Experiments and Results

ERIC Educational Resources Information Center

Raycheva, Regina Pavlova; Angelova, Desislava Ivanova; Vodenova, Pavlina Minkova

2017-01-01

Using a students' workshop as a laboratory, this article summarises the observation of three years' implementation of a new study module for a Bachelor Program in Engineering Design (Interior and Furniture Design) at the University of Forestry, Sofia, Bulgaria. The article offers an analysis of group dynamics and the difficulties and issues…

Study Of The Feasibility And Design Configuration For In-Vehicle Route Guidance, Volume II: Final Report

DOT National Transportation Integrated Search

2000-03-01

Procurement of Intelligent Transportation System (ITS) projects using Federal-aid funds can present challenges that are not typically observed in traditional transportation projects. Many roadway improvement projects involve the two-step "Design-Bid-...

Developing Kindergarten Children's Mathematical Abilities and Character by Using Area Instruction Model

ERIC Educational Resources Information Center

Mardiana, Dinny; Mudrikah, Achmad; Amna, Nurjanah

2016-01-01

This study aimed to describe the application of Area Instruction Model on one of the state kindergarten in Bandung city. The study used a qualitative approach with descriptive qualitative design. Data was obtained through interviews, observation, and documentation. The validity of the analysis was guaranteed through perseverance observation and…

Referentiality in Secondary Teachers' Video Observation of Others' Teaching

ERIC Educational Resources Information Center

Lussi Borer, Valérie; Flandin, Simon; Muller, Alain

2018-01-01

This article presents a study of individual video-based educational sessions with secondary trainee teachers (N = 30) observing others' teaching. Within a Peircian semiotic framework, the study was designed to deepen the researchers' understanding of video-enhanced experience in educational settings beyond the usual research areas of noticing,…

Basic principles of test-negative design in evaluating influenza vaccine effectiveness.

PubMed

Fukushima, Wakaba; Hirota, Yoshio

2017-08-24

Based on the unique characteristics of influenza, the concept of "monitoring" influenza vaccine effectiveness (VE) across the seasons using the same observational study design has been developed. In recent years, there has been a growing number of influenza VE reports using the test-negative design, which can minimize both misclassification of diseases and confounding by health care-seeking behavior. Although the test-negative designs offer considerable advantages, there are some concerns that widespread use of the test-negative design without knowledge of the basic principles of epidemiology could produce invalid findings. In this article, we briefly review the basic concepts of the test-negative design with respect to classic study design such as cohort studies or case-control studies. We also mention selection bias, which may be of concern in some countries where rapid diagnostic testing is frequently used in routine clinical practices, as in Japan. Copyright © 2017. Published by Elsevier Ltd.

Climate Change Professional Development: Design, Implementation, and Initial Outcomes on Teacher Learning, Practice, and Student Beliefs

NASA Astrophysics Data System (ADS)

Shea, Nicole A.; Mouza, Chrystalla; Drewes, Andrea

2016-04-01

In this work, we present the design, implementation, and initial outcomes of the Climate Academy, a hybrid professional development program delivered through a combination of face-to-face and online interactions, intended to prepare formal and informal science teachers (grades 5-16) in teaching about climate change. The Climate Academy was designed around core elements of successful environmental professional development programs and aligned with practices advocated in benchmarked science standards. Data were collected from multiple sources including observations of professional development events, participants' reflections on their learning, and collection of instructional units designed during the Academy. Data were also collected from a focal case study teacher in a middle school setting. Case study data included classroom observations, teacher interviews, and student beliefs toward climate change. Results indicated that the Climate Academy fostered increased learning among participants of both climate science content and pedagogical strategies for teaching about climate change. Additionally, results indicated that participants applied their new learning in the design of climate change instructional units. Finally, results from the case study indicated positive impacts on student beliefs and greater awareness about climate change. Results have implications for the design of professional development programs on climate change, a topic included for the first time in national standards.

An Action Research Study Designed to Implement Student Negotiation to Improve Speaking Classroom Practice in Turkey

ERIC Educational Resources Information Center

Uztosun, Mehmet Sercan; Skinner, Nigel; Cadorath, Jill

2014-01-01

This paper reports the second stage of an action research study designed to improve the effectiveness of speaking classes through negotiating the lesson contents with students. The data were collected through interviews, questionnaires and observations as a way of eliciting students' views. The research, conducted in an English language teaching…

Using Narrative-Based Design Scaffolds within a Mobile Learning Environment to Support Learning Outdoors with Young Children

ERIC Educational Resources Information Center

Seely, Brian J.

2015-01-01

This study aims to advance learning outdoors with mobile devices. As part of the ongoing Tree Investigators design-based research study, this research investigated a mobile application to support observation, identification, and explanation of the tree life cycle within an authentic, outdoor setting. Recognizing the scientific and conceptual…

Beyond Barriers: Encouraging Teacher Use of Feedback Resources. A Report from the Teacher Feedback Resources Project

ERIC Educational Resources Information Center

Morgan, Nicholas; Killion, Joellen

2018-01-01

This report investigates factors that drive teachers to embrace or challenge the use of products and services designed to support improvements in practice. Key elements of the study include: (1) Technology-based resources studied include those designed for video observations, peer feedback and collaboration, online professional learning, and…

As Green as We Think? The Case of the College of Charleston Green Building Initiative

ERIC Educational Resources Information Center

Owens, Katharine A.; Halfacre-Hitchcock, Angela

2006-01-01

Purpose: This paper seeks to disseminate knowledge regarding the experiences of a student team in implementing a campus-level sustainability initiative, outlining the strategy to measure the potential impact of this initiative. Design/methodology/approach: Project design is a case study. Via interviewing and surveys, the study observed student and…

Case-Based Instructional Practices: A Multiple-Case Study from Torts, Marketing, and Online Instructional Design Classes

ERIC Educational Resources Information Center

Jung, Ji yoon

2017-01-01

The purpose of this study is to provide a comprehensive account on case-based instructional practices. Semester-long participant observation records in torts, marketing, and online instructional design classes, instructor interviews, course syllabi and teaching materials were used to describe the within-class complexity of the practices in terms…

Quality of Reporting and Study Design of CKD Cohort Studies Assessing Mortality in the Elderly Before and After STROBE: A Systematic Review

PubMed Central

Brück, Katharina; Methven, Shona; Evans, Rebecca; Stel, Vianda S.; Jager, Kitty J.; Hooft, Lotty; Ben-Shlomo, Yoav; Caskey, Fergus

2016-01-01

Background The STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) statement was published in October 2007 to improve quality of reporting of observational studies. The aim of this review was to assess the impact of the STROBE statement on observational study reporting and study design quality in the nephrology literature. Study Design Systematic literature review. Setting & Population European and North American, Pre-dialysis Chronic Kidney Disease (CKD) cohort studies. Selection Criteria for Studies Studies assessing the association between CKD and mortality in the elderly (>65 years) published from 1st January 2002 to 31st December 2013 were included, following systematic searching of MEDLINE & EMBASE. Predictor Time period before and after the publication of the STROBE statement. Outcome Quality of study reporting using the STROBE statement and quality of study design using the Newcastle Ottawa Scale (NOS), Scottish Intercollegiate Guidelines Network (SIGN) and Critical Appraisal Skills Programme (CASP) tools. Results 37 papers (11 Pre & 26 Post STROBE) were identified from 3621 potential articles. Only four of the 22 STROBE items and their sub-criteria (objectives reporting, choice of quantitative groups and description of and carrying out sensitivity analysis) showed improvements, with the majority of items showing little change between the period before and after publication of the STROBE statement. Pre- and post-period analysis revealed a Manuscript STROBE score increase (median score 77.8% (Inter-quartile range [IQR], 64.7–82.0) vs 83% (IQR, 78.4–84.9, p = 0.05). There was no change in quality of study design with identical median scores in the two periods for NOS (Manuscript NOS score 88.9), SIGN (Manuscript SIGN score 83.3) and CASP (Manuscript CASP score 91.7) tools. Limitations Only 37 Studies from Europe and North America were included from one medical specialty. Assessment of study design largely reliant on good reporting. Conclusions This study highlights continuing deficiencies in the reporting of STROBE items and their sub-criteria in cohort studies in nephrology. There was weak evidence of improvement in the overall reporting quality, with no improvement in methodological quality of CKD cohort studies between the period before and after publication of the STROBE statement. PMID:27168187

NOAA Interest in Small Satellite Solutions for Mitigation of Data Gaps

NASA Astrophysics Data System (ADS)

Caulfield, M.; Tewey, K.; John, P.

2016-12-01

The National Oceanic and Atmospheric Administration (NOAA) is undertaking a strategy to achieve satellite constellation robustness by 2023 to maintain continuity of polar satellite observations, which are central to NOAA's weather forecast capability. NOAA's plans include mitigation activities in the event of a loss of polar observations. In 2017, NOAA will begin development of the Earth Observing Nanosatellite - Microwave (EON-MW). EON-MW is a miniature microwave sounder that approximates the atmospheric profiling capabilities of the Advanced Technology Microwave Sounder (ATMS) instrument on the NOAA Joint Polar Satellite System (JPSS). NOAA is collaborating with the Massachusetts Institute of Technology's Lincoln Laboratory (MIT / LL) on EON-MW, which includes 2 years of risk reduction efforts to further define the EON-MW mission and identify and manage key technical risks. These studies will refine designs and evaluate system trades for operational earth observations from a U-class satellite platform, as well as examine microwave sensor concepts and investigated payload architecture to support microwave frequencies for atmospheric remote sensing. Similar to EON-MW, NOAA is also investigating the potential to mitigate against the loss of the JPSS Cross Track Infrared Sounder (CrIS) data with a CubeSat based mid-wave Infrared sounder. NOAA is collaborating with the Jet Propulsion Laboratory (JPL) to design the Earth Observation Nanosatellite-Infrared (EON-IR). EON-IR will leverage the NASA-JPL CubSat based infrared sounder CubSat Infrared Atmospheric Sounder (CIRAS) mission. In FY 2015 NOAA funded a study to analyze the feasibility of meeting the essential requirements of the CrIS from a CubeSat platform and began exploring the basic design of the EON-IR payload and bus. NOAA will continue to study EON-IR in 2016 by examining ways to modify the CIRAS design to better meet NOAA's observational and operational needs. These modifications will aim to increase mission reliability and increase spatial and spectral resolution.

Towards improved behavioural testing in aquatic toxicology: Acclimation and observation times are important factors when designing behavioural tests with fish.

PubMed

Melvin, Steven D; Petit, Marie A; Duvignacq, Marion C; Sumpter, John P

2017-08-01

The quality and reproducibility of science has recently come under scrutiny, with criticisms spanning disciplines. In aquatic toxicology, behavioural tests are currently an area of controversy since inconsistent findings have been highlighted and attributed to poor quality science. The problem likely relates to limitations to our understanding of basic behavioural patterns, which can influence our ability to design statistically robust experiments yielding ecologically relevant data. The present study takes a first step towards understanding baseline behaviours in fish, including how basic choices in experimental design might influence behavioural outcomes and interpretations in aquatic toxicology. Specifically, we explored how fish acclimate to behavioural arenas and how different lengths of observation time impact estimates of basic swimming parameters (i.e., average, maximum and angular velocity). We performed a semi-quantitative literature review to place our findings in the context of the published literature describing behavioural tests with fish. Our results demonstrate that fish fundamentally change their swimming behaviour over time, and that acclimation and observational timeframes may therefore have implications for influencing both the ecological relevance and statistical robustness of behavioural toxicity tests. Our review identified 165 studies describing behavioural responses in fish exposed to various stressors, and revealed that the majority of publications documenting fish behavioural responses report extremely brief acclimation times and observational durations, which helps explain inconsistencies identified across studies. We recommend that researchers applying behavioural tests with fish, and other species, apply a similar framework to better understand baseline behaviours and the implications of design choices for influencing study outcomes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Model observer design for multi-signal detection in the presence of anatomical noise

NASA Astrophysics Data System (ADS)

Wen, Gezheng; Markey, Mia K.; Park, Subok

2017-02-01

As psychophysical studies are resource-intensive to conduct, model observers are commonly used to assess and optimize medical imaging quality. Model observers are typically designed to detect at most one signal. However, in clinical practice, there may be multiple abnormalities in a single image set (e.g. multifocal multicentric (MFMC) breast cancer), which can impact treatment planning. Prevalence of signals can be different across anatomical regions, and human observers do not know the number or location of signals a priori. As new imaging techniques have the potential to improve multiple-signal detection (e.g. digital breast tomosynthesis may be more effective for diagnosis of MFMC than mammography), image quality assessment approaches addressing such tasks are needed. In this study, we present a model observer to detect multiple signals in an image dataset. A novel implementation of partial least squares (PLS) was developed to estimate different sets of efficient channels directly from the images. The PLS channels are adaptive to the characteristics of signals and the background, and they capture the interactions among signal locations. Corresponding linear decision templates are employed to generate both image-level and location-specific scores on the presence of signals. Our results show that: (1) the model observer can achieve high performance with a reasonably small number of channels; (2) the model observer with PLS channels outperforms that with benchmark modified Laguerre-Gauss channels, especially when realistic signal shapes and complex background statistics are involved; (3) the tasks of clinical interest, and other constraints such as sample size would alter the optimal design of the model observer.

Move the Neighbourhood: Study design of a community-based participatory public open space intervention in a Danish deprived neighbourhood to promote active living.

PubMed

Pawlowski, Charlotte Skau; Winge, Laura; Carroll, Sidse; Schmidt, Tanja; Wagner, Anne Margrethe; Nørtoft, Kamilla Pernille Johansen; Lamm, Bettina; Kural, René; Schipperijn, Jasper; Troelsen, Jens

2017-05-19

A limited amount of research has examined the effect of changing public open spaces on active living. This paper will present the study protocol of a community-based intervention study co-designed in an interdisciplinary collaboration with community members to develop urban installations highly tailored to promote active living among children (10-13-years-old) and seniors (>60-years-old) in a deprived neighbourhood in Copenhagen. The study builds on a quasi-experimental study design with two sub-studies: 1) a children study and 2) a senior study. The interventions will be developed, designed and implemented in collaboration with local children and seniors, respectively, using different co-design tools and methods. We will evaluate the effect of the interventions on children's and senior's use of the new-built urban installations using accelerometers in combination with GPS as well as systematic observation using the System for Observing Play and Recreation in Communities (SOPARC). A process evaluation with focus groups consisting of the various stakeholders in the two sub-studies will be used to gain knowledge of the intervention processes. The paper presents new approaches in the field of public open space interventions through interdisciplinary collaboration, participatory co-design approach and combination of measurements. Using both effect and process evaluations the study will provide unique insights in the role and importance of the interdisciplinary collaboration, participatory processes, and tailoring changes in public open space to local needs and wishes. These results can be used to guide urban renewal projects in deprived neighbourhoods in the future. Retrospectively registered with study ID ISRCTN50036837 . Date of registration: 16 December 2016.

CURRENT PRACTICES OBSERVED IN DESIGN AND DRAFTING OCCUPATIONS.

ERIC Educational Resources Information Center

SQUIRES, CARL E.

DATA WHICH HAD SIGNIFICANCE FOR DESIGN AND DRAFTING CURRICULUMS WERE COLLECTED BY DIRECT OBSERVATION OF 21 DESIGN AND DRAFTING FACTORS WITHIN 16 SELECTED INDUSTRIAL COMPANIES EMPLOYING 869 DESIGNERS AND DRAFTSMEN. OBSERVATIONS COVERED (1) THE NUMBER OF DESIGN AND DRAFTING EMPLOYEES, (2) THE SYSTEM OF DRAFTING ROOM ORGANIZATION, (3) JOB…

The Ganymede Interior Structure, and Magnetosphere Observer (GISMO) Mission Concept

NASA Technical Reports Server (NTRS)

Lynch, K. L.; Smith, I. B.; Singer, K. N.; Vogt, M. F.; Blackburn, D. G.; Chaffin, M.; Choukroun, M.; Ehsan, N.; DiBraccio, G. A.; Gibbons, L. J.;

Teaching Demands and Adaptive Curriculum Management.

ERIC Educational Resources Information Center

Flinders, David

A qualitative case study was designed to explore the work experience of six high school English teachers. Teachers were observed over a five month period. No formal, systematic rating scale or observation instruments were used; the observer relied upon his experience as a high school teacher and on specialized training in curriculum theory and…

Local Linear Observed-Score Equating

ERIC Educational Resources Information Center

Wiberg, Marie; van der Linden, Wim J.

2011-01-01

Two methods of local linear observed-score equating for use with anchor-test and single-group designs are introduced. In an empirical study, the two methods were compared with the current traditional linear methods for observed-score equating. As a criterion, the bias in the equated scores relative to true equating based on Lord's (1980)…

Learning by Observing a Peer's Teaching Situation

ERIC Educational Resources Information Center

Hendry, Graham D.; Bell, Amani; Thomson, Kate

2014-01-01

This article reports on a study of academics who observed their colleagues' teaching at a large research-intensive university in Australia. These academics had completed peer observation as part of a foundations programme designed for those new to teaching or new to the university. Survey responses and interview transcripts form the basis of an…

Observer Training Manual for the Changing Teacher Practice Study. Revised Manual.

ERIC Educational Resources Information Center

Barnes, Susan

This observer training manual was developed as a central component of a research effort, Changing Teacher Practice (CTP), which was designed to increase the frequency of effective teaching behaviors and staff development strategies in an ongoing school system. The observations focused on two major aspects of classroom teaching--instruction and…

Hierarchy of evidence: where observational studies fit in and why we need them.

PubMed

Hoppe, Daniel J; Schemitsch, Emil H; Morshed, Saam; Tornetta, Paul; Bhandari, Mohit

2009-05-01

Although randomized controlled designs are considered the so-called gold standard in medical trials and sit atop the hierarchy of evidence in evidence-based medicine, there are situations in which they are impractical or unethical to undertake, especially in surgical trials. Then, observational studies often provide the best source of information. In this paper, we use examples from the literature to explain the importance of observational studies in furthering the boundaries of orthopaedic surgery and knowledge of musculoskeletal disorders.

Study on observation planning of LAMOST focal plane positioning system and its simulation

NASA Astrophysics Data System (ADS)

Zhai, Chao; Jin, Yi; Peng, Xiaobo; Xing, Xiaozheng

2006-06-01

Fiber Positioning System of LAMOST focal plane based on subarea thinking, adopts a parallel controllable positioning plan, the structure is designed as a round area and overlapped each other in order to eliminate the un-observation region. But it also makes the observation efficiency of the system become an important problem. In this paper According to the system, the model of LAMOST focal plane Observation Planning including 4000 fiber positioning units is built, Stars are allocated using netflow algorithm and mechanical collisions are diminished through the retreat algorithm, then the simulation of the system's observation efficiency is carried out. The problem of observation efficiency of LAMOST focal plane is analysed systemic and all-sided from the aspect of overlapped region, fiber positioning units, observation radius, collisions and so on. The observation efficiency of the system in theory is describes and the simulation indicates that the system's observation efficiency is acceptable. The analyses play an indicative role on the design of the LAMOST focal plane structure.

The importance of user centered design methods applied to the design of a new workstation: a case study.

PubMed

Duschenes, Ronaldo; Mendes, Andressa; Betiol, Adriana; Barreto, Suzana

2012-01-01

This paper presents a case study of the application of user centered design methodologies in the product development for a line of ergonomic office furniture. The study aimed to analyze the experience of using a workstation from the perspective of two groups of users, installers and end users. The observation of users in their natural context of use not only allowed the development team to identify key needs and strategies of the users, transforming them into design solutions, but mainly it warned them of the importance and impact of user involvement in the product development cycle.

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

PubMed

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

2017-03-28

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

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

PubMed Central

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

2010-01-01

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

Teaching science to 8th graders by engaging them in a design and technology activity: A case study

NASA Astrophysics Data System (ADS)

Sidawi, Mai M.

This study described how students can apply science concepts to a Design and Technology task. It also examined whether the students could transfer their scientific knowledge to their design of technology. The study was conducted at an urban school in Philadelphia where a sample of 36 eighth grade students were taught a science unit, Energy, Machines, and Motion, and engaged in a technology design task that was chosen based on the scientific content of the unit. Two approaches of relating teaching science to technological design were observed and described. Through the first approach, the students were given technology lessons in addition to their science lessons. This was to provide them with the technological knowledge that they needed in designing technology such as learning about the design process, selection of appropriate materials, and selection of appropriate tools and how to use them. Also, the students were taught the social skills that will enable them to develop an effective collaborative relationship with their peers such as conflict-management and brainstorming. Through the second approach, the students were taught the science unit and then at the end of the unit the students were given the design task as an assessment of their scientific knowledge. The students' experience of designing technology for each approach was described. The study was conducted using multiple tools and instruments such as observation, videotaping, interviews, and testing. The students were also given the survey PATT-USA to measure their attitude toward technology. The study showed that the students' learning of science was impacted by their weak prerequisite knowledge in science, their poor verbal and written communication skills and their style as dependent learners. Also, the study showed the great impact of the school and classroom cultures on the participation of the students in a Design and Technology activity. The students in this study showed great resistant to participating in a Design and Technology activity. The study linked that to the culture of the classroom where the technology period was considered by the students a period of "free time" to be spent mainly on the computer, playing educational games or engaged in short term, non-demanding projects.

Design of experiments for zeroth and first-order reaction rates.

PubMed

Amo-Salas, Mariano; Martín-Martín, Raúl; Rodríguez-Aragón, Licesio J

2014-09-01

This work presents optimum designs for reaction rates experiments. In these experiments, time at which observations are to be made and temperatures at which reactions are to be run need to be designed. Observations are performed along time under isothermal conditions. Each experiment needs a fixed temperature and so the reaction can be measured at the designed times. For these observations under isothermal conditions over the same reaction a correlation structure has been considered. D-optimum designs are the aim of our work for zeroth and first-order reaction rates. Temperatures for the isothermal experiments and observation times, to obtain the most accurate estimates of the unknown parameters, are provided in these designs. D-optimum designs for a single observation in each isothermal experiment or for several correlated observations have been obtained. Robustness of the optimum designs for ranges of the correlation parameter and comparisons of the information gathered by different designs are also shown. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Evaluating Usability of Radiology Information Systems in Hospitals of Tabriz University of Medical Sciences.

PubMed

Rezaei-Hachesu, Peyman; Pesianian, Esmaeil; Mohammadian, Mohsen

2016-02-01

Radiology information system (RIS) in order to reduce workload and improve the quality of services must be well-designed. Heuristic evaluation is one of the methods that understand usability problems with the least time, cost and resources. The aim of present study is to evaluate the usability of RISs in hospitals. This is a cross-sectional descriptive study (2015) that uses heuristic evaluation method to evaluate the usability of RIS used in 3 hospitals of Tabriz city. The data are collected using a standard checklist based on 13 principles of Nielsen Heuristic evaluation method. Usability of RISs was investigated based on the number of components observed from Nielsen principles and problems of usability based on the number of non-observed components as well as non-existent or unrecognizable components. by evaluation of RISs in each of the hospitals 1, 2 and 3, total numbers of observed components were obtained as 173, 202 and 196, respectively. It was concluded that the usability of RISs in the studied population, on average and with observing 190 components of the 291 components related to the 13 principles of Nielsen is 65.41 %. Furthermore, problems of usability were obtained as 26.35%. The established and visible nature of some components such as response time of application, visual feedbacks, colors, view and design and arrangement of software objects cause more attention to these components as principal components in designing UI software. Also, incorrect analysis before system design leads to a lack of attention to secondary needs like Help software and security issues.

Quality of Reporting and Study Design of CKD Cohort Studies Assessing Mortality in the Elderly Before and After STROBE: A Systematic Review.

PubMed

Rao, Anirudh; Brück, Katharina; Methven, Shona; Evans, Rebecca; Stel, Vianda S; Jager, Kitty J; Hooft, Lotty; Ben-Shlomo, Yoav; Caskey, Fergus

2016-01-01

The STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) statement was published in October 2007 to improve quality of reporting of observational studies. The aim of this review was to assess the impact of the STROBE statement on observational study reporting and study design quality in the nephrology literature. Systematic literature review. European and North American, Pre-dialysis Chronic Kidney Disease (CKD) cohort studies. Studies assessing the association between CKD and mortality in the elderly (>65 years) published from 1st January 2002 to 31st December 2013 were included, following systematic searching of MEDLINE & EMBASE. Time period before and after the publication of the STROBE statement. Quality of study reporting using the STROBE statement and quality of study design using the Newcastle Ottawa Scale (NOS), Scottish Intercollegiate Guidelines Network (SIGN) and Critical Appraisal Skills Programme (CASP) tools. 37 papers (11 Pre & 26 Post STROBE) were identified from 3621 potential articles. Only four of the 22 STROBE items and their sub-criteria (objectives reporting, choice of quantitative groups and description of and carrying out sensitivity analysis) showed improvements, with the majority of items showing little change between the period before and after publication of the STROBE statement. Pre- and post-period analysis revealed a Manuscript STROBE score increase (median score 77.8% (Inter-quartile range [IQR], 64.7-82.0) vs 83% (IQR, 78.4-84.9, p = 0.05). There was no change in quality of study design with identical median scores in the two periods for NOS (Manuscript NOS score 88.9), SIGN (Manuscript SIGN score 83.3) and CASP (Manuscript CASP score 91.7) tools. Only 37 Studies from Europe and North America were included from one medical specialty. Assessment of study design largely reliant on good reporting. This study highlights continuing deficiencies in the reporting of STROBE items and their sub-criteria in cohort studies in nephrology. There was weak evidence of improvement in the overall reporting quality, with no improvement in methodological quality of CKD cohort studies between the period before and after publication of the STROBE statement.

Methods to systematically review and meta-analyse observational studies: a systematic scoping review of recommendations.

PubMed

Mueller, Monika; D'Addario, Maddalena; Egger, Matthias; Cevallos, Myriam; Dekkers, Olaf; Mugglin, Catrina; Scott, Pippa

2018-05-21

Systematic reviews and meta-analyses of observational studies are frequently performed, but no widely accepted guidance is available at present. We performed a systematic scoping review of published methodological recommendations on how to systematically review and meta-analyse observational studies. We searched online databases and websites and contacted experts in the field to locate potentially eligible articles. We included articles that provided any type of recommendation on how to conduct systematic reviews and meta-analyses of observational studies. We extracted and summarised recommendations on pre-defined key items: protocol development, research question, search strategy, study eligibility, data extraction, dealing with different study designs, risk of bias assessment, publication bias, heterogeneity, statistical analysis. We summarised recommendations by key item, identifying areas of agreement and disagreement as well as areas where recommendations were missing or scarce. The searches identified 2461 articles of which 93 were eligible. Many recommendations for reviews and meta-analyses of observational studies were transferred from guidance developed for reviews and meta-analyses of RCTs. Although there was substantial agreement in some methodological areas there was also considerable disagreement on how evidence synthesis of observational studies should be conducted. Conflicting recommendations were seen on topics such as the inclusion of different study designs in systematic reviews and meta-analyses, the use of quality scales to assess the risk of bias, and the choice of model (e.g. fixed vs. random effects) for meta-analysis. There is a need for sound methodological guidance on how to conduct systematic reviews and meta-analyses of observational studies, which critically considers areas in which there are conflicting recommendations.

Prospective Dutch colorectal cancer cohort: an infrastructure for long-term observational, prognostic, predictive and (randomized) intervention research.

PubMed

Burbach, J P M; Kurk, S A; Coebergh van den Braak, R R J; Dik, V K; May, A M; Meijer, G A; Punt, C J A; Vink, G R; Los, M; Hoogerbrugge, N; Huijgens, P C; Ijzermans, J N M; Kuipers, E J; de Noo, M E; Pennings, J P; van der Velden, A M T; Verhoef, C; Siersema, P D; van Oijen, M G H; Verkooijen, H M; Koopman, M

2016-11-01

Systematic evaluation and validation of new prognostic and predictive markers, technologies and interventions for colorectal cancer (CRC) is crucial for optimizing patients' outcomes. With only 5-15% of patients participating in clinical trials, generalizability of results is poor. Moreover, current trials often lack the capacity for post-hoc subgroup analyses. For this purpose, a large observational cohort study, serving as a multiple trial and biobanking facility, was set up by the Dutch Colorectal Cancer Group (DCCG). The Prospective Dutch ColoRectal Cancer cohort is a prospective multidisciplinary nationwide observational cohort study in the Netherlands (yearly CRC incidence of 15 500). All CRC patients (stage I-IV) are eligible for inclusion, and longitudinal clinical data are registered. Patients give separate consent for the collection of blood and tumor tissue, filling out questionnaires, and broad randomization for studies according to the innovative cohort multiple randomized controlled trial design (cmRCT), serving as an alternative study design for the classic RCT. Objectives of the study include: 1) systematically collected long-term clinical data, patient-reported outcomes and biomaterials from daily CRC practice; and 2) to facilitate future basic, translational and clinical research including interventional and cost-effectiveness studies for both national and international research groups with short inclusion periods, even for studies with stringent inclusion criteria. Seven months after initiation 650 patients have been enrolled, eight centers participate, 15 centers await IRB approval and nine embedded cohort- or cmRCT-designed studies are currently recruiting patients. This cohort provides a unique multidisciplinary data, biobank, and patient-reported outcomes collection initiative, serving as an infrastructure for various kinds of research aiming to improve treatment outcomes in CRC patients. This comprehensive design may serve as an example for other tumor types.

Radiology workstation for mammography: preliminary observations, eyetracker studies, and design

NASA Astrophysics Data System (ADS)

Beard, David V.; Johnston, Richard E.; Pisano, Etta D.; Hemminger, Bradley M.; Pizer, Stephen M.

1991-07-01

For the last four years, the UNC FilmPlane project has focused on constructing a radiology workstation facilitating CT interpretations equivalent to those with film and viewbox. Interpretation of multiple CT studies was originally chosen because handling such large numbers of images was considered to be one of the most difficult tasks that could be performed with a workstation. The authors extend the FilmPlane design to address mammography. The high resolution and contrast demands coupled with the number of images often cross- compared make mammography a difficult challenge for the workstation designer. This paper presents the results of preliminary work with workstation interpretation of mammography. Background material is presented to justify why the authors believe electronic mammographic workstations could improve health care delivery. The results of several observation sessions and a preliminary eyetracker study of multiple-study mammography interpretations are described. Finally, tentative conclusions of what a mammographic workstation might look like and how it would meet clinical demand to be effective are presented.

Bias reduction in repeated-measures observational studies by the use of propensity score: the case of enteral sedation for critically ill patients.

PubMed

Umbrello, Michele; Mistraletti, Giovanni; Corbella, Davide; Cigada, Marco; Salini, Silvia; Morabito, Alberto; Iapichino, Gaetano

2012-12-01

Within the evidence-based medicine paradigm, randomized controlled trials represent the "gold standard" to produce reliable evidence. Indeed, planning and implementing randomized controlled trials in critical care medicine presents limitations because of intrinsic and structural problems. As a consequence, observational studies still occur frequently. In these cases, propensity score (PS) (probability of receiving a treatment conditional on observed covariates) is an increasingly used technique to adjust the results. Few studies addressed the specific issue of a PS correction of repeated-measures designs. Three techniques for correcting the analysis of nonrandomized designs (matching, stratification, regression adjustment) are presented in a tutorial form and applied to a real case study: the comparison between intravenous and enteral sedative therapy in the intensive care unit setting. After showing the results before and after the use of PS, we suggest that such a tool allows to partially overcoming the bias associated with the observational nature of the study. It permits to correct the estimates for any observed covariate, while unobserved confounders cannot be controlled for. Propensity score represents a useful additional tool to estimate the effects of treatments in nonrandomized studies. In the case study, an enteral sedation approach was equally effective to an intravenous regime, allowing for a lower level of sedation and spare of resources. Copyright © 2012 Elsevier Inc. All rights reserved.

Analysis of pre-service physics teacher skills designing simple physics experiments based technology

NASA Astrophysics Data System (ADS)

Susilawati; Huda, C.; Kurniawan, W.; Masturi; Khoiri, N.

2018-03-01

Pre-service physics teacher skill in designing simple experiment set is very important in adding understanding of student concept and practicing scientific skill in laboratory. This study describes the skills of physics students in designing simple experiments based technologicall. The experimental design stages include simple tool design and sensor modification. The research method used is descriptive method with the number of research samples 25 students and 5 variations of simple physics experimental design. Based on the results of interviews and observations obtained the results of pre-service physics teacher skill analysis in designing simple experimental physics charged technology is good. Based on observation result, pre-service physics teacher skill in designing simple experiment is good while modification and sensor application are still not good. This suggests that pre-service physics teacher still need a lot of practice and do experiments in designing physics experiments using sensor modifications. Based on the interview result, it is found that students have high enough motivation to perform laboratory activities actively and students have high curiosity to be skilled at making simple practicum tool for physics experiment.

Effectiveness of adjuvant radiotherapy in patients with oropharyngeal and floor of mouth squamous cell carcinoma and concomitant histological verification of singular ipsilateral cervical lymph node metastasis (pN1-state) - A prospective multicenter randomized controlled clinical trial using a comprehensive cohort design

PubMed Central

2009-01-01

Background Modern radiotherapy plays an important role in therapy of advanced head and neck carcinomas. However, no clinical studies have been published addressing the effectiveness of postoperative radiotherapy in patients with small tumor (pT1, pT2) and concomitant ipsilateral metastasis of a single lymph node (pN1), which would provide a basis for a general treatment recommendation. Methods/Design The present study is a non-blinded, prospective, multi-center randomized controlled trial (RCT). As the primary clinical endpoint, overall-survival in patients receiving postoperative radiation therapy vs. patients without adjuvant therapy following curative intended surgery is compared. The aim of the study is to enroll 560 adult males and females for 1:1 randomization to one of the two treatment arms (irradiation/no irradiation). Since patients with small tumor (T1/T2) but singular lymph node metastasis are rare and the amount of patients consenting to randomization is not predictable in advance, all patients rejecting randomization will be treated as preferred and enrolled in a prospective observational study (comprehensive cohort design) after giving informed consent. This observational part of the trial will be performed with maximum consistency to the treatment and observation protocol of the RCT. Because the impact of patient preference for a certain treatment option is not calculable, parallel design of RCT and observational study may provide a maximum of evidence and efficacy for evaluation of treatment outcome. Secondary clinical endpoints are as follows: incidence and time to tumor relapse (locoregional relapse, lymph node involvement and distant metastatic spread), Quality of life as reported by EORTC (QLQ-C30 with H&N 35 module), and time from operation to orofacial rehabilitation. All tumors represent a homogeneous clinical state and therefore additional investigation of protein expression levels within resection specimen may serve for establishment of surrogate parameters of patient outcome. Conclusion The inherent challenges of a rare clinical condition (pN1) and two substantially different therapy arms would limit the practicality of a classical randomized study. The concept of a Comprehensive Cohort Design combines the preference of a randomized study, with the option of careful data interpretation within an observational study. Trial registration ClinicalTrials.gov: NCT00964977 PMID:20028566

[Fitting Monocurve and Bicurve (Soper-McGuire design) rigid gas-permeable contact lenses in keratoconus patients: a prospective randomized comparative clinical trial].

PubMed

Coral-Ghanem, Cleusa; Alves, Milton Ruiz

2008-01-01

To evaluate the clinical performance of Monocurve and Bicurve (Soper-McGuire design) rigid gas-permeable contact lens fitting in patients with keratoconus. A prospective and randomized comparative clinical trial was conducted with a minimum follow-up of six months in two groups of 63 patients. One group was fitted with Monocurve contact lenses and the other with Bicurve Soper-McGuire design. Study variables included fluoresceinic pattern of lens-to-cornea fitting relationship, location and morphology of the cone, presence and degree of punctate keratitis and other corneal surface alterations, topographic changes, visual acuity for distance corrected with contact lenses and survival analysis for remaining with the same contact lens design during the study. During the follow-up there was a decrease in the number of eyes with advanced and central cones fitted with Monocurve lenses, and an increase in those fitted with Soper-McGuire design. In the Monocurve group, a flattening of both the steepest and the flattest keratometric curve was observed. In the Soper-McGuire group, a steepening of the flattest keratometric curve and a flattening of the steepest keratometric curve were observed. There was a decrease in best-corrected visual acuity with contact lens in the Monocurve group. Survival analysis for the Monocurve lens was 60.32% and for the Soper-McGuire was 71.43% at a mean follow-up of six months. This study showed that due to the changes observed in corneal topography, the same contact lens design did not provide an ideal fitting for all patients during the follow-up period. The Soper-McGuire lenses had a better performance than the Monocurve lenses in advanced and central keratoconus.

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

Plotkowski, A.; Rios, O.; Sridharan, N.

Our present research in metal additive manufacturing (AM) focuses on designing processing parameters around existing alloys designed for traditional manufacturing. However, to maximize the benefits of AM, alloys should be designed to specifically take advantage of the unique thermal conditions of these processes. Furthermore, our study focuses on the development of a design methodology for alloys in AM, using a newly developed Al-Ce alloy as an initial case study. To evaluate the candidacy of this system for fusion based additive manufacturing, single-line laser melts were made on cast Al-12Ce plates using three different beam velocities (100, 200, and 300 mm/min).more » The microstructure was evaluated in the as-melted and heat treated conditions (24 hrs at 300°C). An extremely fine microstructure was observed within the weld pools, evolving from eutectic at the outer solid-liquid boundaries to a primary Al FCC dendritic/cellular structure nearer the melt-pool centerline. We rationalized the observed microstructures through the construction of a microstructure selection map for the Al-Ce binary system, which will be used to enable future alloy design. Interestingly, the heat treated samples exhibited no microstructural coarsening.« less

Wear Behavior of an Unstable Knee: Stabilization via Implant Design?

PubMed Central

Reinders, Jörn; Kretzer, Jan Philippe

2014-01-01

Background. Wear-related failures and instabilities are frequent failure mechanisms of total knee replacements. High-conforming designs may provide additional stability for the joint. This study analyzes the effects of a ligamentous insufficiency on the stability and the wear behavior of a high-conforming knee design. Methods. Two simulator wear tests were performed on a high-conforming total knee replacement design. In the first, a ligamentous-stable knee replacement with a sacrificed anterior cruciate ligament was simulated. In the second, a ligamentous-unstable knee with additionally insufficient posterior cruciate ligament and medial collateral ligament was simulated. Wear was determined gravimetrically and wear particles were analyzed. Implant kinematics was recorded during simulation. Results. Significantly higher wear rates (P ≤ 0.001) were observed for the unstable knee (14.58 ± 0.56 mg/106 cycles) compared to the stable knee (7.97 ± 0.87 mg/106 cycles). A higher number of wear particles with only small differences in wear particle characteristics were observed. Under unstable knee conditions, kinematics increased significantly for translations and rotations (P ≤ 0.01). This increase was mainly attributed to higher tibial posterior translation and internal rotations. Conclusion. Higher kinematics under unstable test conditions is a result of insufficient stabilization via implant design. Due to the higher kinematics, increased wear was observed in this study. PMID:25276820

[Methodological design for the National Survey Violence Against Women in Mexico].

PubMed

Olaiz, Gustavo; Franco, Aurora; Palma, Oswaldo; Echarri, Carlos; Valdez, Rosario; Herrera, Cristina

2006-01-01

To describe the methodology, the research designs used, the estimation and sample selection, variable definitions, collection instruments, and operative design and analytical procedures for the National Survey Violence Against Women in Mexico. A complex (two-step) cross-sectional study was designed and the qualitative design was carried out using in-depth interviews and participant observation in health care units. We obtained for the quantitative study a total of 26 240 interviews in women users of health services and 2 636 questionnaires for health workers; the survey is representative of the 32 Mexican states. For the qualitative study 26 in-depth interviews were conducted with female users and 60 interviews with health workers in the States of Quintana Roo, Coahuila and the Federal District.

Viewing the Reviewing: An Observational Study of the Use of an Interactive Digital Video To Help Teach the Concepts of Design Inspection Reviews.

ERIC Educational Resources Information Center

Love, Matthew

"Design Inspection Reviews" are structured meetings in which participants follow certain rules of procedure and behavior when conducting detailed readings of design plans to identify errors and misunderstandings. The technique is widely used in the software engineering industry, where it is demonstrably more effective than testing at…

Study design and hierarchy of evidence for surgical decision making.

PubMed

Sprague, Sheila; McKay, Paula; Thoma, Achilleas

2008-04-01

This article provides a historical overview of the hierarchy of evidence for surgical decision making and discusses key study designs in the hierarchy of evidence. This encompasses meta-analyses, randomized controlled trials, and observational studies, including cohort and case-controlled studies, case series and case reports, and basic science studies. This article also reviews the principles and importance of evidence-based plastic surgery and describes several systems to rate the strength of the scientific evidence.

A system decomposition approach to the design of functional observers

NASA Astrophysics Data System (ADS)

Fernando, Tyrone; Trinh, Hieu

2014-09-01

This paper reports a system decomposition that allows the construction of a minimum-order functional observer using a state observer design approach. The system decomposition translates the functional observer design problem to that of a state observer for a smaller decomposed subsystem. Functional observability indices are introduced, and a closed-form expression for the minimum order required for a functional observer is derived in terms of those functional observability indices.

STARPROBE: A design study for an X-ray imaging instrument

NASA Technical Reports Server (NTRS)

1981-01-01

The primary objective of the X-ray imaging telescope on STARPROBE is the acquisition of very high spacial resolution observations during the spacecraft's perihelion passage. Design parameters, telescope prefilters, and structural and thermal analyses of the equipment are described and discussed. It is believed that the spatial resolution of the information recorded by the baseline design would be at least a factor of 10 better than can be reasonably expected from Earth orbit. Thermal models used in the study are also discussed.

Investigation of Microcavitation-Induced Effects using in Vitro Models for Traumatic Brain Injury

DTIC Science & Technology

2016-08-25

four MOSFET switches (IXFB38N I OOQ2) stacking in series . The designing details of such stacking circuit can be found in [25] . In brief, the gate... time of the mechanical vibration of the piezotransducer. The on- time in this study was limited to ~2 s. B. Microbubble chamber design Rev. Sci...60 s. This long collapse time may be favored for biological studies where the observation of time evolution is of essence. We purposely designed the

Incidence and Outcomes of Cardiopulmonary Resuscitation in Pediatric Intensive Care Units

PubMed Central

Berg, Robert A.; Nadkarni, Vinay M.; Clark, Amy E.; Moler, Frank; Meert, Kathleen; Harrison, Rick E.; Newth, Christopher J. L.; Sutton, Robert M.; Wessel, David L.; Berger, John T.; Carcillo, Joseph; Dalton, Heidi; Heidemann, Sabrina; Shanley, Thomas P.; Zuppa, Athena F.; Doctor, Allan; Tamburro, Robert F.; Jenkins, Tammara L.; Dean, J. Michael; Holubkov, Richard; Pollack, Murray M.

2015-01-01

Objective To determine the incidence of cardiopulmonary resuscitation (CPR) in pediatric intensive care units (PICU) and subsequent outcomes. Design, Setting, and Patients Multi-center prospective observational study of children 30 minutes, p30 minutes of CPR. Conclusions These data establish that contemporary PICU CPR, including long durations of CPR, results in high rates of survival to hospital discharge (45%) and favorable neurologic outcomes among survivors (89%). Rates of survival with favorable neurologic outcomes were similar among cardiac and non-cardiac patients. The rigorous prospective, observational study design avoided the limitations of missing data and potential selection biases inherent in registry and administrative data. PMID:26646466

NIRcam-NIRSpec GTO Observations of Galaxy Evolution

NASA Astrophysics Data System (ADS)

Rieke, Marcia J.; Ferruit, Pierre; Alberts, Stacey; Bunker, Andrew; Charlot, Stephane; Chevallard, Jacopo; Dressler, Alan; Egami, Eiichi; Eisenstein, Daniel; Endsley, Ryan; Franx, Marijn; Frye, Brenda L.; Hainline, Kevin; Jakobsen, Peter; Lake, Emma Curtis; Maiolino, Roberto; Rix, Hans-Walter; Robertson, Brant; Stark, Daniel; Williams, Christina; Willmer, Christopher; Willott, Chris J.

2017-06-01

The NIRSpec and and NIRCam GTO Teams are planning a joint imaging and spectroscopic study of the high redshift universe. By virtue of planning a joint program which includes medium and deep near- and mid-infrared imaging surveys and multi-object spectroscopy (MOS) of sources in the same fields, we have learned much about planning observing programs for each of the instruments and using them in parallel mode to maximize photon collection time. The design and rationale for our joint program will be explored in this talk with an emphasis on why we have chosen particular suites of filters and spectroscopic resolutions, why we have chosen particular exposure patterns, and how we have designed the parallel observations. The actual observations that we intend on executing will serve as examples of how to layout mosaics and MOS observations to maximize observing efficiency for surveys with JWST.

Advancement of the Wide-angle JEM-EUSO Optical System with Holographic and Fresnel Lenses

NASA Technical Reports Server (NTRS)

Takizawa, Y.; Adams, J.H.

2007-01-01

JEM-EUSO is a space mission to observe extremely high-energy cosmic rays, evolved from the previous design studies of EUSO. It is adjusted for the Japan Experiment Module (JEM) of the International Space Station (ISS). JEM-EUSO uses a wide-angle refractive telescope in near-ultraviolet wavelength region to observe from ISS the time-and-space-resolved atmospheric fluorescence images of the extensive air showers. The JEM-EUSO optics is re-designed after the ESA-Phase A studies to upgrade the light-collecting-power by using a new material CYTOP, and its overall light-collecting power is about 1.5 times higher than the ESA-Phase A baseline optics. We describe in this paper an optimized optics design that maximizes the sensitivity of JEM-EUSO, and the results of the optics manufacturing tests.

Learning Clinical Skills during Bedside Teaching Encounters in General Practice: A Video-Observational Study with Insights from Activity Theory

ERIC Educational Resources Information Center

Ajjawi, Rola; Rees, Charlotte; Monrouxe, Lynn V.

2015-01-01

Purpose: This paper aims to explore how opportunities for learning clinical skills are negotiated within bedside teaching encounters (BTEs). Bedside teaching, within the medical workplace, is considered essential for helping students develop their clinical skills. Design/methodology/approach: An audio and/or video observational study examining…

The Effects of Safety Discrimination Training and Frequent Safety Observations on Safety-Related Behavior

ERIC Educational Resources Information Center

Taylor, Matthew A.; Alvero, Alicia M.

2012-01-01

The intent of the present study was to assess the effects of discrimination training only and in combination with frequent safety observations on five participants' safety-related behavior in a simulated office setting. The study used a multiple-baseline design across safety-related behaviors. Across all participants and behavior, safety improved…

Teaching Statistical Inference for Causal Effects in Experiments and Observational Studies

ERIC Educational Resources Information Center

Rubin, Donald B.

2004-01-01

Inference for causal effects is a critical activity in many branches of science and public policy. The field of statistics is the one field most suited to address such problems, whether from designed experiments or observational studies. Consequently, it is arguably essential that departments of statistics teach courses in causal inference to both…

76 FR 28233 - Agency Forms Undergoing Paperwork Reduction Act Review

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-16

... basis for research, design, and evaluation of interventions for schools seeking to prevent or reduce the.... Proposed Project Crime Prevention Through Environmental Design: Linking Observed School Environments with... priorities included in the Center's published research agenda focus on studying how physical environments...

40 CFR Appendix D to Part 132 - Great Lakes Water Quality Initiative Methodology for the Development of Wildlife Criteria

Code of Federal Regulations, 2014 CFR

2014-07-01

...-conducted study of 90 days or greater designed to observe subchronic or chronic effects as defined in this document. 2. The avian data must come from at least one well-conducted study of 70 days or greater designed... poorly defined comparative toxicokinetic and toxicodynamic parameters between mammals and birds. However...

40 CFR Appendix D to Part 132 - Great Lakes Water Quality Initiative Methodology for the Development of Wildlife Criteria

Code of Federal Regulations, 2011 CFR

2011-07-01

...-conducted study of 90 days or greater designed to observe subchronic or chronic effects as defined in this document. 2. The avian data must come from at least one well-conducted study of 70 days or greater designed... poorly defined comparative toxicokinetic and toxicodynamic parameters between mammals and birds. However...

40 CFR Appendix D to Part 132 - Great Lakes Water Quality Initiative Methodology for the Development of Wildlife Criteria

Code of Federal Regulations, 2012 CFR

2012-07-01

...-conducted study of 90 days or greater designed to observe subchronic or chronic effects as defined in this document. 2. The avian data must come from at least one well-conducted study of 70 days or greater designed... poorly defined comparative toxicokinetic and toxicodynamic parameters between mammals and birds. However...

40 CFR Appendix D to Part 132 - Great Lakes Water Quality Initiative Methodology for the Development of Wildlife Criteria

Code of Federal Regulations, 2013 CFR

2013-07-01

...-conducted study of 90 days or greater designed to observe subchronic or chronic effects as defined in this document. 2. The avian data must come from at least one well-conducted study of 70 days or greater designed... poorly defined comparative toxicokinetic and toxicodynamic parameters between mammals and birds. However...

40 CFR Appendix D to Part 132 - Great Lakes Water Quality Initiative Methodology for the Development of Wildlife Criteria

Code of Federal Regulations, 2010 CFR

2010-07-01

...-conducted study of 90 days or greater designed to observe subchronic or chronic effects as defined in this document. 2. The avian data must come from at least one well-conducted study of 70 days or greater designed... poorly defined comparative toxicokinetic and toxicodynamic parameters between mammals and birds. However...

Equating TIMSS Mathematics Subtests with Nonlinear Equating Methods Using NEAT Design: Circle-Arc Equating Approaches

ERIC Educational Resources Information Center

Ozdemir, Burhanettin

2017-01-01

The purpose of this study is to equate Trends in International Mathematics and Science Study (TIMSS) mathematics subtest scores obtained from TIMSS 2011 to scores obtained from TIMSS 2007 form with different nonlinear observed score equating methods under Non-Equivalent Anchor Test (NEAT) design where common items are used to link two or more test…

Rurality and Nursing Home Quality: Evidence from the 2004 National Nursing Home Survey

ERIC Educational Resources Information Center

Kang, Yu; Meng, Hongdao; Miller, Nancy A.

2011-01-01

Purpose of the Study: To evaluate the impact of rural geographic location on nursing home quality of care in the United States. Design and Methods: The study used cross-sectional observational design. We obtained resident- and facility-level data from 12,507 residents in 1,174 nursing homes from the 2004 National Nursing Home Survey. We used…

The presence of field geologists in Mars-like terrain

NASA Technical Reports Server (NTRS)

Mcgreevy, Michael W.

1992-01-01

Methods of ethnographic observation and analysis have been coupled with object-oriented analysis and design concepts to begin the development of a clear path from observations in the field to the design of virtual presence systems. The existence of redundancies in field geology and presence allowed for the application of methods for understanding complex systems. As a result of this study, some of these redundancies have been characterized. Those described are all classes of continuity relations, including the continuities of continuous existence, context-constituent continuities, and state-process continuities. The discussion of each includes statements of general relationships, logical consequences of these, and hypothetical situations in which the relationships would apply. These are meant to aid in the development of a theory of presence. The discussion also includes design considerations, providing guidance for the design of virtual planetary exploration systems and other virtual presence systems. Converging evidence regarding continuity in presence is found in the nature of psychological dissociation. Specific methodological refinements should enhance ecological validity in subsequent field studies, which are in progress.

Design progress of the solar UV-Vis-IR telescope (SUVIT) aboard SOLAR-C

NASA Astrophysics Data System (ADS)

Katsukawa, Y.; Ichimoto, K.; Suematsu, Y.; Hara, H.; Kano, R.; Shimizu, T.; Matsuzaki, K.

2013-09-01

We present a design progress of the Solar UV-Vis-IR Telescope (SUVIT) aboard the next Japanese solar mission SOLAR-C. SUVIT has an aperture diameter of ~1.4 m for achieving spectro-polarimetric observations with spatial and temporal resolution exceeding the Hinode Solar Optical Telescope (SOT). We have studied structural and thermal designs of the optical telescope as well as the optical interface between the telescope and the focal plane instruments. The focal plane instruments are installed into two packages, filtergraph and spectrograph packages. The spectropolarimeter is the instrument dedicated to accurate polarimetry in the three spectrum windows at 525 nm, 854 nm, and 1083 nm for observing magnetic fields at both the photospheric and chromospheric layers. We made optical design of the spectrograph accommodating the conventional slit spectrograph and the integral field unit (IFU) for two-dimensional coverage. We are running feasibility study of the IFU using fiber arrays consisting of rectangular cores.

Cautionary tales in the interpretation of observational studies of effects of clinical interventions.

PubMed

Scott, I A; Attia, J

2017-02-01

Observational studies of the effectiveness of clinical interventions are proliferating as more 'real-world' clinical data (so called 'big data') are gathered from clinical registries, administrative datasets and electronic health records. While well-conducted randomised controlled trials (RCT) remain the scientific standard in assessing the efficacy of clinical interventions, well-designed observational studies may add to the evidence base of effectiveness in situations where RCT are of limited value or very difficult to perform. Rather than dismissing observational studies, we need to determine what circumstances may justify doing an observational study and when the study is sufficiently rigorous to be considered reasonably trustworthy. This article proposes criteria by which users of the literature might make such determinations. © 2016 Royal Australasian College of Physicians.

Hinode/EIS science planning and operations tools

NASA Astrophysics Data System (ADS)

Rainnie, Jonn A.

2016-07-01

We present the design, implementation and maintenance of the suite of software enabling scientists to design and schedule Hinode/EIS1 operations. The total of this software is the EIS Science Planning Tools (EISPT), and is predominately written in IDL (Interactive Data Language), coupled with SolarSoft (SSW), an IDL library developed for solar missions. Hinode is a multi-instrument and wavelength mission designed to observe the Sun. It is a joint Japan/UK/US consortium (with ESA and Norwegian involvement). Launched in September 2006, its principal scientific goals are to study the Sun's variability and the causes of solar activity. Hinode operations are coordinated at ISAS (Tokyo, Japan). A daily Science Operations meeting is attended by the instrument teams and the spacecraft team. Nominally, science plan uploads cover periods of two or three days. When the forthcoming operations have been agreed, the necessary spacecraft operations parameters are created. These include scheduling for spacecraft pointing and ground stations. The Extreme UV Imaging Spectrometer (EIS) instrument, led by the UK (the PI institute is MSSL), is designed to observe the emission spectral lines of the solar atmosphere. Observations are composed of reusable, hierarchical components, including lines lists (wavelengths of spectral lines), rasters (exposure times, line list, etc.) and studies (defines one or more rasters). Studies are the basic unit of "timeline" scheduling. They are a useful construct for generating more complex sequences of observations, reducing the planning burden. Instrument observations must first be validated. An initial requirement was that operations be shared equally by the 3 main EIS teams (Japan, UK and US). Hence, a major design focus of the software was "Remote Operations", whereby any scientist in any location can run the software, schedule a science plan and send it to the spacecraft commanding team. It would then be validated and combined with the science plans of the other instruments. Then uploaded to the spacecraft. As for any space mission, telemetry size and rate are important constraints. For each planning cycle the instruments are issued a maximum data allocation. EISPT interactively calculates the telemetry requirements of each observation and plan. Autonomous operations was a challenging concept designed to observe the early onset of various dynamic events, including solar flares. The planning cycle precluded observers responding to such short-term events. Hence, the instrument can be run in a (low-telemetry) "hunter" mode at a suitable target. Upon detecting an event the current observation ceases and another automatically begins at the event location. This "response" observation involves a smaller field-of-view and higher cadence. It's impossible to predict if this mechanism will be activated, and if so how much telemetry is acquired. The EISPT has operated successfully since it was deployed in November 2006. Nominally it is used six days a week. It has been maintained and updated as required to take account of changing mission operations. A large update was made in 2013/14 to develop the facility to coordinate observations with other solar missions (SDO/AIA and IRIS).

A review of published analyses of case-cohort studies and recommendations for future reporting.

PubMed

Sharp, Stephen J; Poulaliou, Manon; Thompson, Simon G; White, Ian R; Wood, Angela M

2014-01-01

The case-cohort study design combines the advantages of a cohort study with the efficiency of a nested case-control study. However, unlike more standard observational study designs, there are currently no guidelines for reporting results from case-cohort studies. Our aim was to review recent practice in reporting these studies, and develop recommendations for the future. By searching papers published in 24 major medical and epidemiological journals between January 2010 and March 2013 using PubMed, Scopus and Web of Knowledge, we identified 32 papers reporting case-cohort studies. The median subcohort sampling fraction was 4.1% (interquartile range 3.7% to 9.1%). The papers varied in their approaches to describing the numbers of individuals in the original cohort and the subcohort, presenting descriptive data, and in the level of detail provided about the statistical methods used, so it was not always possible to be sure that appropriate analyses had been conducted. Based on the findings of our review, we make recommendations about reporting of the study design, subcohort definition, numbers of participants, descriptive information and statistical methods, which could be used alongside existing STROBE guidelines for reporting observational studies.

Preservice Elementary Teachers' Knowledge of Observable Moon Phases and Pattern of Change in Phases

ERIC Educational Resources Information Center

Trundle, Kathy Cabe; Atwood, Ronald K.; Christopher, John E.

2006-01-01

The purpose of this study was to describe selected content knowledge held by 52 preservice elementary teachers about the observable phases of the moon and the monthly pattern of change in observable phases. Data were obtained from participants in a physics course before and after they received inquiry-based instruction designed to promote…

NASA Cold Land Processes Experiment (CLPX 2002/03): Ground-based and near-surface meteorological observations

Treesearch

Kelly Elder; Don Cline; Angus Goodbody; Paul Houser; Glen E. Liston; Larry Mahrt; Nick Rutter

2009-01-01

A short-term meteorological database has been developed for the Cold Land Processes Experiment (CLPX). This database includes meteorological observations from stations designed and deployed exclusively for CLPXas well as observations available from other sources located in the small regional study area (SRSA) in north-central Colorado. The measured weather parameters...

Exploring Differences in Measurement and Reporting of Classroom Observation Inter-Rater Reliability

ERIC Educational Resources Information Center

Wilhelm, Anne Garrison; Gillespie Rouse, Amy; Jones, Francesca

2018-01-01

Although inter-rater reliability is an important aspect of using observational instruments, it has received little theoretical attention. In this article, we offer some guidance for practitioners and consumers of classroom observations so that they can make decisions about inter-rater reliability, both for study design and in the reporting of data…

Live Versus Televised Observations of Social Behavior in Preschool Children.

ERIC Educational Resources Information Center

Paulson, F. Leon

1972-01-01

An investigation to compare systematic behavioral observations made live with those made on television was conducted. The study was designed to answer three questions: (1) Is there a difference in the agreement between observers (Os) when both view an event Live and when both view the same event on Television? (2) Is there a difference in…

Woman Friendly Mosque, Features and Facilities: A Case Study on Masjid Sultan Ibrahim, Universiti Tun Hussein Onn Malaysia

NASA Astrophysics Data System (ADS)

Suratkon, A.; Salam, N. N. Abd; Rahmat, M. H.; Arhan, A. S. Mohd; Wahab, I. Abd; Ghaffar, S. A.

2017-12-01

Mosque has gone through a long and complex development throughout the Muslim’s history which involved the interrelation between its functions and its design. During the process, many aspects of its design were reconfigured including the female facilities in the mosque. In Malaysia, there is a progressive movement to transform the roles and functions of the mosque from exclusive place for prayers and seclusion to a community center. Nevertheless, there are still a numbers of muslim women voices their frustration towards the facilities provided to them in the mosque. Indirectly, this has discourage participation of women in the mosque. The objective of this paper is to investigate the opinions and needs of muslim women in a mosque and to propose appropriate features and facilities for a female-friendly mosque. The study explored through a field observation and a set of questionnaires, which involves a case study of Masjid Sultan Ibrahim in Universiti Tun Hussein Onn Malaysia. The field observation was carried out to analyze its current conditions, facilities, design and features. On the other hand, a set of questionnaire was distributed to the women visitors who were mainly students and staffs as to get their insight on this issue. From the field observation and the survey distributed, it was clearly seen that the facilities provided for the female users were still not up to the standard of a ‘women-friendly mosque’. Some proposals were provided to improve on the current condition and to be taken into consideration by future designers in designing a mosque.

The value of including observational studies in systematic reviews was unclear: a descriptive study.

PubMed

Seida, Jennifer; Dryden, Donna M; Hartling, Lisa

2014-12-01

To evaluate (1) how often observational studies are included in comparative effectiveness reviews (CERs); (2) the rationale for including observational studies; (3) how data from observational studies are appraised, analyzed, and graded; and (4) the impact of observational studies on strength of evidence (SOE) and conclusions. Descriptive study of 23 CERs published through the Effective Health Care Program of the U.S. Agency for Healthcare Research and Quality. Authors searched for observational studies in 20 CERs, of which 18 included a median of 11 (interquartile range, 2-31) studies. Sixteen CERs incorporated the observational studies in their SOE assessments. Seventy-eight comparisons from 12 CERs included evidence from both trials and observational studies; observational studies had an impact on SOE and conclusions for 19 (24%) comparisons. There was diversity across the CERs regarding decisions to include observational studies; study designs considered; and approaches used to appraise, synthesize, and grade SOE. Reporting and methods guidance are needed to ensure clarity and consistency in how observational studies are incorporated in CERs. It was not always clear that observational studies added value in light of the additional resources needed to search for, select, appraise, and analyze such studies. Copyright © 2014 Elsevier Inc. All rights reserved.

Bayesian data analysis in observational comparative effectiveness research: rationale and examples.

PubMed

Olson, William H; Crivera, Concetta; Ma, Yi-Wen; Panish, Jessica; Mao, Lian; Lynch, Scott M

2013-11-01

Many comparative effectiveness research and patient-centered outcomes research studies will need to be observational for one or both of two reasons: first, randomized trials are expensive and time-consuming; and second, only observational studies can answer some research questions. It is generally recognized that there is a need to increase the scientific validity and efficiency of observational studies. Bayesian methods for the design and analysis of observational studies are scientifically valid and offer many advantages over frequentist methods, including, importantly, the ability to conduct comparative effectiveness research/patient-centered outcomes research more efficiently. Bayesian data analysis is being introduced into outcomes studies that we are conducting. Our purpose here is to describe our view of some of the advantages of Bayesian methods for observational studies and to illustrate both realized and potential advantages by describing studies we are conducting in which various Bayesian methods have been or could be implemented.

Precision, time, and cost: a comparison of three sampling designs in an emergency setting.

PubMed

Deitchler, Megan; Deconinck, Hedwig; Bergeron, Gilles

2008-05-02

The conventional method to collect data on the health, nutrition, and food security status of a population affected by an emergency is a 30 x 30 cluster survey. This sampling method can be time and resource intensive and, accordingly, may not be the most appropriate one when data are needed rapidly for decision making. In this study, we compare the precision, time and cost of the 30 x 30 cluster survey with two alternative sampling designs: a 33 x 6 cluster design (33 clusters, 6 observations per cluster) and a 67 x 3 cluster design (67 clusters, 3 observations per cluster). Data for each sampling design were collected concurrently in West Darfur, Sudan in September-October 2005 in an emergency setting. Results of the study show the 30 x 30 design to provide more precise results (i.e. narrower 95% confidence intervals) than the 33 x 6 and 67 x 3 design for most child-level indicators. Exceptions are indicators of immunization and vitamin A capsule supplementation coverage which show a high intra-cluster correlation. Although the 33 x 6 and 67 x 3 designs provide wider confidence intervals than the 30 x 30 design for child anthropometric indicators, the 33 x 6 and 67 x 3 designs provide the opportunity to conduct a LQAS hypothesis test to detect whether or not a critical threshold of global acute malnutrition prevalence has been exceeded, whereas the 30 x 30 design does not. For the household-level indicators tested in this study, the 67 x 3 design provides the most precise results. However, our results show that neither the 33 x 6 nor the 67 x 3 design are appropriate for assessing indicators of mortality. In this field application, data collection for the 33 x 6 and 67 x 3 designs required substantially less time and cost than that required for the 30 x 30 design. The findings of this study suggest the 33 x 6 and 67 x 3 designs can provide useful time- and resource-saving alternatives to the 30 x 30 method of data collection in emergency settings.

Precision, time, and cost: a comparison of three sampling designs in an emergency setting

PubMed Central

Deitchler, Megan; Deconinck, Hedwig; Bergeron, Gilles

2008-01-01

The conventional method to collect data on the health, nutrition, and food security status of a population affected by an emergency is a 30 × 30 cluster survey. This sampling method can be time and resource intensive and, accordingly, may not be the most appropriate one when data are needed rapidly for decision making. In this study, we compare the precision, time and cost of the 30 × 30 cluster survey with two alternative sampling designs: a 33 × 6 cluster design (33 clusters, 6 observations per cluster) and a 67 × 3 cluster design (67 clusters, 3 observations per cluster). Data for each sampling design were collected concurrently in West Darfur, Sudan in September-October 2005 in an emergency setting. Results of the study show the 30 × 30 design to provide more precise results (i.e. narrower 95% confidence intervals) than the 33 × 6 and 67 × 3 design for most child-level indicators. Exceptions are indicators of immunization and vitamin A capsule supplementation coverage which show a high intra-cluster correlation. Although the 33 × 6 and 67 × 3 designs provide wider confidence intervals than the 30 × 30 design for child anthropometric indicators, the 33 × 6 and 67 × 3 designs provide the opportunity to conduct a LQAS hypothesis test to detect whether or not a critical threshold of global acute malnutrition prevalence has been exceeded, whereas the 30 × 30 design does not. For the household-level indicators tested in this study, the 67 × 3 design provides the most precise results. However, our results show that neither the 33 × 6 nor the 67 × 3 design are appropriate for assessing indicators of mortality. In this field application, data collection for the 33 × 6 and 67 × 3 designs required substantially less time and cost than that required for the 30 × 30 design. The findings of this study suggest the 33 × 6 and 67 × 3 designs can provide useful time- and resource-saving alternatives to the 30 × 30 method of data collection in emergency settings. PMID:18454866

Two Approaches to Engineering Design:Observations in sTEm Education

ERIC Educational Resources Information Center

Kelley, Todd R.; Brenner, Daniel C.; Pieper, Jon T.

2010-01-01

A comparative study was conducted to compare two approaches to engineering design curriculum across different schools (inter-school) and across two curricula "Project Lead the Way and Engineering Projects in Community Service" (inter-curricula). The researchers collected curricula material including handouts, lesson plans, guides,…

Polynomial fuzzy observer designs: a sum-of-squares approach.

PubMed

Tanaka, Kazuo; Ohtake, Hiroshi; Seo, Toshiaki; Tanaka, Motoyasu; Wang, Hua O

2012-10-01

This paper presents a sum-of-squares (SOS) approach to polynomial fuzzy observer designs for three classes of polynomial fuzzy systems. The proposed SOS-based framework provides a number of innovations and improvements over the existing linear matrix inequality (LMI)-based approaches to Takagi-Sugeno (T-S) fuzzy controller and observer designs. First, we briefly summarize previous results with respect to a polynomial fuzzy system that is a more general representation of the well-known T-S fuzzy system. Next, we propose polynomial fuzzy observers to estimate states in three classes of polynomial fuzzy systems and derive SOS conditions to design polynomial fuzzy controllers and observers. A remarkable feature of the SOS design conditions for the first two classes (Classes I and II) is that they realize the so-called separation principle, i.e., the polynomial fuzzy controller and observer for each class can be separately designed without lack of guaranteeing the stability of the overall control system in addition to converging state-estimation error (via the observer) to zero. Although, for the last class (Class III), the separation principle does not hold, we propose an algorithm to design polynomial fuzzy controller and observer satisfying the stability of the overall control system in addition to converging state-estimation error (via the observer) to zero. All the design conditions in the proposed approach can be represented in terms of SOS and are symbolically and numerically solved via the recently developed SOSTOOLS and a semidefinite-program solver, respectively. To illustrate the validity and applicability of the proposed approach, three design examples are provided. The examples demonstrate the advantages of the SOS-based approaches for the existing LMI approaches to T-S fuzzy observer designs.

Case-control Studies on the Effectiveness of Breast Cancer Screening: Insights from the UK Age Trial.

PubMed

van der Waal, Daniëlle; Broeders, Mireille J M; Verbeek, André L M; Duffy, Stephen W; Moss, Sue M

2015-07-01

Ongoing breast cancer screening programs can only be evaluated using observational study designs. Most studies have observed a reduction in breast cancer mortality, but design differences appear to have resulted in different estimates. Direct comparison of case-control and trial analyses gives more insight into this variation. Here, we performed case-control analyses within the randomized UK Age Trial. The Age Trial assessed the effect of screening on breast cancer mortality in women ages 40-49 years. In our approach, case subjects were defined as breast cancer deaths between trial entry (1991-1997) and 2004. Women were ages 39-41 years at entry. For every case subject, five control subjects were selected. All case subjects were included in analyses of screening invitation (356 case subjects, 1,780 controls), whereas analyses of attendance were restricted to women invited to screening (105 case subjects, 525 age-matched controls). Odds ratios (OR) were estimated with conditional logistic regression. We used and compared two methods to correct for self-selection bias. Screening invitation resulted in a breast cancer mortality reduction of 17% (95% confidence interval [CI]: -36%, +6%), similar to trial results. Different exposure definitions and self-selection adjustments influenced the observed breast cancer mortality reduction. Depending on the method, "ever screened" appeared to be associated with a small reduction (OR: 0.86, 95% CI: 0.40, 1.89) or no reduction (OR: 1.02, 95% CI: 0.48, 2.14) using the two methods of correction. Recent attendance resulted in an adjusted mortality reduction of 36% (95% CI: -69%, +31%) or 45% (95% CI: -71%, +5%). Observational studies, and particularly case-control studies, are an important monitoring tool for breast cancer screening programs. The focus should be on diminishing bias in observational studies and gaining a better understanding of the influence of study design on estimates of mortality reduction.

Effectiveness of adjuvant radiotherapy in patients with oropharyngeal and floor of mouth squamous cell carcinoma and concomitant histological verification of singular ipsilateral cervical lymph node metastasis (pN1-state)--a prospective multicenter randomized controlled clinical trial using a comprehensive cohort design.

PubMed

Moergel, Maximilian; Jahn-Eimermacher, Antje; Krummenauer, Frank; Reichert, Torsten E; Wagner, Wilfried; Wendt, Thomas G; Werner, Jochen A; Al-Nawas, Bilal

2009-12-23

Modern radiotherapy plays an important role in therapy of advanced head and neck carcinomas. However, no clinical studies have been published addressing the effectiveness of postoperative radiotherapy in patients with small tumor (pT1, pT2) and concomitant ipsilateral metastasis of a single lymph node (pN1), which would provide a basis for a general treatment recommendation. The present study is a non-blinded, prospective, multi-center randomized controlled trial (RCT). As the primary clinical endpoint, overall-survival in patients receiving postoperative radiation therapy vs. patients without adjuvant therapy following curative intended surgery is compared. The aim of the study is to enroll 560 adult males and females for 1:1 randomization to one of the two treatment arms (irradiation/no irradiation). Since patients with small tumor (T1/T2) but singular lymph node metastasis are rare and the amount of patients consenting to randomization is not predictable in advance, all patients rejecting randomization will be treated as preferred and enrolled in a prospective observational study (comprehensive cohort design) after giving informed consent. This observational part of the trial will be performed with maximum consistency to the treatment and observation protocol of the RCT. Because the impact of patient preference for a certain treatment option is not calculable, parallel design of RCT and observational study may provide a maximum of evidence and efficacy for evaluation of treatment outcome. Secondary clinical endpoints are as follows: incidence and time to tumor relapse (locoregional relapse, lymph node involvement and distant metastatic spread), Quality of life as reported by EORTC (QLQ-C30 with H&N 35 module), and time from operation to orofacial rehabilitation. All tumors represent a homogeneous clinical state and therefore additional investigation of protein expression levels within resection specimen may serve for establishment of surrogate parameters of patient outcome. The inherent challenges of a rare clinical condition (pN1) and two substantially different therapy arms would limit the practicality of a classical randomized study. The concept of a Comprehensive Cohort Design combines the preference of a randomized study, with the option of careful data interpretation within an observational study. ClinicalTrials.gov: NCT00964977.

Case Study Observational Research: A Framework for Conducting Case Study Research Where Observation Data Are the Focus.

PubMed

Morgan, Sonya J; Pullon, Susan R H; Macdonald, Lindsay M; McKinlay, Eileen M; Gray, Ben V

2017-06-01

Case study research is a comprehensive method that incorporates multiple sources of data to provide detailed accounts of complex research phenomena in real-life contexts. However, current models of case study research do not particularly distinguish the unique contribution observation data can make. Observation methods have the potential to reach beyond other methods that rely largely or solely on self-report. This article describes the distinctive characteristics of case study observational research, a modified form of Yin's 2014 model of case study research the authors used in a study exploring interprofessional collaboration in primary care. In this approach, observation data are positioned as the central component of the research design. Case study observational research offers a promising approach for researchers in a wide range of health care settings seeking more complete understandings of complex topics, where contextual influences are of primary concern. Future research is needed to refine and evaluate the approach.

Control concepts for the alleviation of windshears and gusts

NASA Technical Reports Server (NTRS)

Rynaski, E. G.; Govindaraj, K. S.

1982-01-01

Automatic control system design methods for gust and shear alleviation were studied. It is shown that automatic gust/shear alleviation systems can be quite effective if both throttle and elevator are used in harmony to produce the forces and moments required to counter the effects of the windshear. Regulation with respect to ground speed or airspeed results in very similar system designs. The application of the NASA total energy probe in the detection of windshear and criteria for alleviation is considered. The theory and application of robust output observers is extended. Design examples show how implementation of the control laws can be accomplished using observers, and thereby resulting in less complex control system configurations.

DAG telescope site studies and infrastructure for possible international co-operations

NASA Astrophysics Data System (ADS)

Yerli, Sinan K.; Yeşilyaprak, Cahit; Keskin, Onur; Alis, Sinan

2016-07-01

The selected site for the 4 m DAG (Eastern Anatolian Observatory in Turkish) telescope is at "Karakaya Ridge", at 3170 m altitude (3150 m after summit management). The telescope's optical design is performed by the DAG technical team to allow infrared observation at high angular resolution, with its adaptive optics system to be built in Turkey. In this paper; a brief introduction about DAG telescope design; planned instrumentation; the meteorological data collected from 2008, clear night counts, short-term DIMM observations; current infrastructure to hold auxiliary telescopes; auxiliary buildings to assist operations; the observatory design; and coating unit plans will be presented along with possible collaboration possibilities in terms of instrumentation and science programs.

An Exploratory Study of Skin Problems Experienced by UK Nursing Home Residents Using Different Pad Designs.

PubMed

Clarke-OʼNeill, Sinead; Farbrot, Anne; Lagerstedt, Marie-Louise; Cottenden, Alan; Fader, Mandy

2015-01-01

The primary aim of this study was to determine whether the severity of incontinence-associated dermatitis (IAD) among nursing home-based incontinence pad users varies between pad designs. A second aim was to examine the utility of a simple method for reporting skin health problems in which healthcare assistants were asked to record basic observational data at each pad change. Randomized, multiple crossover, observational, exploratory. Twenty-one men and 57 women using absorbent continence products to contain urinary and/or fecal incontinence were recruited from 10 nursing homes in London and the south of England. A day-time variant and a night-time variant of each of the 4 main disposable pad designs on the market for moderate/heavy incontinence were tested: (1) insert pads with stretch pants; (2) 1-piece all-in-one diapers; (3) pull-up pants; and (4) belted/T-shape diapers. All pad variants for day-time use had an absorption capacity of 1900 mL ± 20% (measured using ISO 11948-1 International Standards Organization) while the capacity of night-time variants was 2400 mL ± 20%. Each resident used each of the 4 pad designs (day-time and night-time variants) for 2 weeks and the order of testing was randomized by nursing home. Skin health data were collected using 2 methods in parallel. Method 1 comprised visual observation by researchers (1 observation per pad design; 4 observations in total over 8 weeks). In method 2, healthcare assistants logged observational data on skin health at every pad change for the 8 weeks. The primary outcome variable was severity of the most severe skin problem noted by the researcher for each resident, and for each pad design (method 1). Descriptive data on skin care methods used in the nursing homes were also collected using short questionnaires and researcher observation. No significant differences in the severity or incidence of skin problems were found between observations using the 4 pad designs. However, a wide range of skin conditions was recorded that made classification difficult; the skin was often marked with creases from absorbent products, temporary marks, and pink/purple discoloration. We observed few cases of the severe erythema, rashes, and vesicles that are commonly used descriptors in previous skin tools. Nevertheless, the collected data reflect an abundance of skin problems that were difficult to categorize neatly. Researcher observations (method 1) showed that nearly all the residents (96%) had at least 1 IAD skin problem recorded over the 8-week period and 64% of residents had at least 1 problem that was rated as maximum severity. Healthcare assistants logged skin problems on 6.1% of pad changes. The discrepancy between researcher and healthcare assistant data appears to be largely due to healthcare assistants sometimes discounting low-grade IAD as normal for that population. Incontinence-associated dermatitis is common among nursing home residents who use incontinence pads, and it is often severe. No evidence was found that any design of pad was more likely than any others to be associated with skin problems. The method devised to enable healthcare assistants to record basic observational data on skin health in the diaper area at each pad change (Method 2) proved simple to use but still resulted in substantial underreporting of IAD, suggesting that further work is needed to develop a tool that more successfully encourages them to log and treat IAD problems.

Science-Grade Observing Systems as Process Observatories: Mapping and Understanding Nonlinearity and Multiscale Memory with Models and Observations

NASA Astrophysics Data System (ADS)

Barros, A. P.; Wilson, A. M.; Miller, D. K.; Tao, J.; Genereux, D. P.; Prat, O.; Petersen, W. A.; Brunsell, N. A.; Petters, M. D.; Duan, Y.

2015-12-01

Using the planet as a study domain and collecting observations over unprecedented ranges of spatial and temporal scales, NASA's EOS (Earth Observing System) program was an agent of transformational change in Earth Sciences over the last thirty years. The remarkable space-time organization and variability of atmospheric and terrestrial moist processes that emerged from the analysis of comprehensive satellite observations provided much impetus to expand the scope of land-atmosphere interaction studies in Hydrology and Hydrometeorology. Consequently, input and output terms in the mass and energy balance equations evolved from being treated as fluxes that can be used as boundary conditions, or forcing, to being viewed as dynamic processes of a coupled system interacting at multiple scales. Measurements of states or fluxes are most useful if together they map, reveal and/or constrain the underlying physical processes and their interactions. This can only be accomplished through an integrated observing system designed to capture the coupled physics, including nonlinear feedbacks and tipping points. Here, we first review and synthesize lessons learned from hydrometeorology studies in the Southern Appalachians and in the Southern Great Plains using both ground-based and satellite observations, physical models and data-assimilation systems. We will specifically focus on mapping and understanding nonlinearity and multiscale memory of rainfall-runoff processes in mountainous regions. It will be shown that beyond technical rigor, variety, quantity and duration of measurements, the utility of observing systems is determined by their interpretive value in the context of physical models to describe the linkages among different observations. Second, we propose a framework for designing science-grade and science-minded process-oriented integrated observing and modeling platforms for hydrometeorological studies.

Is the large simple trial design used for comparative, post-approval safety research? A review of a clinical trials registry and the published literature.

PubMed

Reynolds, Robert F; Lem, Joanna A; Gatto, Nicolle M; Eng, Sybil M

2011-10-01

Post-approval, observational drug safety studies face well known difficulties in controlling for confounding, particularly confounding by indication for drug use. A study design that addresses confounding by indication is the large simple trial (LST). LSTs are characterized by large sample sizes, often in the thousands; broad entry criteria consistent with the approved medication label; randomization based on equipoise, i.e. neither physician nor patient believes that one treatment option is superior; minimal, streamlined data collection requirements; objectively-measured endpoints (e.g. death, hospitalization); and follow-up that minimizes interventions or interference with normal clinical practice. In theory then, the LST is a preferred study design for drug and vaccine safety research because it controls for biases inherent to observational research while still providing results that are generalizable to 'real-world' use. To evaluate whether LSTs are used for comparative safety evaluation and if the design is, in fact, advantageous compared with other designs, we conducted a review of the published literature (1949 through 31 December 2010) and the ClinicalTrials.gov registry (2000 through 31 December 2010). Thirteen ongoing or completed safety LSTs were identified. The design has rarely been used in comparative drug safety research, which is due to the operational, financial and scientific hurdles of implementing the design. The studies that have been completed addressed important clinical questions and, in some cases, led to re-evaluation of medical practice. We conclude the design has demonstrated utility for comparative safety research of medicines and vaccines if the necessary scientific and operational conditions for its use are met.

Towards a Viable Curriculum: A Comparative Study of Curricula at the East African School of Library and Information Science and the Departments of Library and Information Studies of the Universities of Wales, Botswana, and Capetown

ERIC Educational Resources Information Center

Kigongo-Bukenya, I. M. N.

2003-01-01

Applying a qualitative research design and using questionnaires, interviews, observation, focus groups, and debate, this study examines the phenomena and implications of change on LIS curricula, the stakeholders' perception of the current curriculum, the processes of curriculum design and review, and the impact of social, economic, political and…

The Neighbourhood Effects on Health and Well-being (NEHW) study.

PubMed

O'Campo, Patricia; Wheaton, Blair; Nisenbaum, Rosane; Glazier, Richard H; Dunn, James R; Chambers, Catharine

2015-01-01

Many cross-sectional studies of neighbourhood effects on health do not employ strong study design elements. The Neighbourhood Effects on Health and Well-being (NEHW) study, a random sample of 2412 English-speaking Toronto residents (age 25-64), utilises strong design features for sampling neighbourhoods and individuals, characterising neighbourhoods using a variety of data sources, measuring a wide range of health outcomes, and for analysing cross-level interactions. We describe here methodological issues that shaped the design and analysis features of the NEHW study to ensure that, while a cross-sectional sample, it will advance the quality of evidence emerging from observational studies. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Facilitating Toddler Interaction through Interior Environmental Design in a Child Care Setting.

ERIC Educational Resources Information Center

Wynn, Ruth L.; And Others

This study was a joint undertaking of interior environmental designers and a child developmentalist. The goal of the study was to increase peer interation between children in two classes held in one classroom. Children were observed for 7 weeks, in three periods: weeks 2 and 3 (time 1); weeks 4 and 5 (time 2); and weeks 6 and 7 (time 3). Observers…

Simulations as a tool for higher mass resolution spectrometer: Lessons from existing observations

NASA Astrophysics Data System (ADS)

Nicolaou, Georgios; Yamauchi, Masatoshi; Nilsson, Hans; Wieser, Martin; Fedorov, Andrei

2017-04-01

Scientific requirements of each mission are crucial for the instrument's design. Ion tracing simulations of instruments can be helpful to characterize their performance, identify their limitations and improving the design for future missions. However, simulations provide the best performance in ideal case, and the actual response is determined by many other factors. Therefore, simulations should be compared with observations when possible. Characterizing the actual response of a running instrument gives valuable lessons for the future design of test instruments with the same detection principle before spending resources to build and calibrate them. In this study we use an ion tracing simulation of the Ion Composition Analyser (ICA) on board ROSETTA, in order to characterize its response and to compare it with the observations. It turned out that, due to the complicated unexpected response of the running instrument, the heavy cometary ions and molecules are sometimes difficult to be resolved. However, preliminary simulation of a slightly modified design predicts much higher mass resolution. Even after considering the complicated unexpected response, we safely expect that the modified design can resolve most abundant heavy atomic ions (e.g., O^+) and molecular ions (e.g., N_2+ and O_2^+). We show the simulation results for both designs and ICA data.

Comparison of safety effect estimates obtained from empirical Bayes before-after study, propensity scores-potential outcomes framework, and regression model with cross-sectional data.

PubMed

Wood, Jonathan S; Donnell, Eric T; Porter, Richard J

2015-02-01

A variety of different study designs and analysis methods have been used to evaluate the performance of traffic safety countermeasures. The most common study designs and methods include observational before-after studies using the empirical Bayes method and cross-sectional studies using regression models. The propensity scores-potential outcomes framework has recently been proposed as an alternative traffic safety countermeasure evaluation method to address the challenges associated with selection biases that can be part of cross-sectional studies. Crash modification factors derived from the application of all three methods have not yet been compared. This paper compares the results of retrospective, observational evaluations of a traffic safety countermeasure using both before-after and cross-sectional study designs. The paper describes the strengths and limitations of each method, focusing primarily on how each addresses site selection bias, which is a common issue in observational safety studies. The Safety Edge paving technique, which seeks to mitigate crashes related to roadway departure events, is the countermeasure used in the present study to compare the alternative evaluation methods. The results indicated that all three methods yielded results that were consistent with each other and with previous research. The empirical Bayes results had the smallest standard errors. It is concluded that the propensity scores with potential outcomes framework is a viable alternative analysis method to the empirical Bayes before-after study. It should be considered whenever a before-after study is not possible or practical. Copyright © 2014 Elsevier Ltd. All rights reserved.

Measuring the Process and Quality of Informed Consent for Clinical Research: Development and Testing

PubMed Central

Cohn, Elizabeth Gross; Jia, Haomiao; Smith, Winifred Chapman; Erwin, Katherine; Larson, Elaine L.

2013-01-01

Purpose/Objectives To develop and assess the reliability and validity of an observational instrument, the Process and Quality of Informed Consent (P-QIC). Design A pilot study of the psychometrics of a tool designed to measure the quality and process of the informed consent encounter in clinical research. The study used professionally filmed, simulated consent encounters designed to vary in process and quality. Setting A major urban teaching hospital in the northeastern region of the United States. Sample 63 students enrolled in health-related programs participated in psychometric testing, 16 students participated in test-retest reliability, and 5 investigator-participant dyads were observed for the actual consent encounters. Methods For reliability and validity testing, students watched and rated videotaped simulations of four consent encounters intentionally varied in process and content and rated them with the proposed instrument. Test-retest reliability was established by raters watching the videotaped simulations twice. Inter-rater reliability was demonstrated by two simultaneous but independent raters observing an actual consent encounter. Main Research Variables The essential elements of information and communication for informed consent. Findings The initial testing of the P-QIC demonstrated reliable and valid psychometric properties in both the simulated standardized consent encounters and actual consent encounters in the hospital setting. Conclusions The P-QIC is an easy-to-use observational tool that provides a quick assessment of the areas of strength and areas that need improvement in a consent encounter. It can be used in the initial trainings of new investigators or consent administrators and in ongoing programs of improvement for informed consent. Implications for Nursing The development of a validated observational instrument will allow investigators to assess the consent process more accurately and evaluate strategies designed to improve it. PMID:21708532

Photography To Enhance Aesthetic Skills.

ERIC Educational Resources Information Center

McIsaac, Marina Stock

Recognizing that photography in the classroom is highly motivating in that it offers a unique vehicle for communicating ideas visually, this study was designed to isolate variables which can be both observed and evaluated in photographs and for which instruction can be designed. Relationships among the technical and aesthetic qualities in…

Exploring Employee Engagement from the Employee Perspective: Implications for HRD

ERIC Educational Resources Information Center

Shuck, M. Brad; Rocco, Tonette S.; Albornoz, Carlos A.

2011-01-01

Purpose: The purpose of this paper is to examine an employee's unique experience of being engaged in their work. Design/methodology/approach: Following Yin's case study design method, researchers collected documents, conducted semi-structured interviews and recorded observations at a large multinational service corporation ranked as one of the…

Using Virtual Reality with and without Gaming Attributes for Academic Achievement

ERIC Educational Resources Information Center

Vogel, Jennifer J.; Greenwood-Ericksen, Adams; Cannon-Bowers, Jan; Bowers, Clint A.

2006-01-01

A subcategory of computer-assisted instruction (CAI), games have additional attributes such as motivation, reward, interactivity, score, and challenge. This study used a quasi-experimental design to determine if previous findings generalize to non simulation-based game designs. Researchers observed significant improvement in the overall population…

Using R in experimental design with BIBD: An application in health sciences

NASA Astrophysics Data System (ADS)

Oliveira, Teresa A.; Francisco, Carla; Oliveira, Amílcar; Ferreira, Agostinho

2016-06-01

Considering the implementation of an Experimental Design, in any field, the experimenter must pay particular attention and look for the best strategies in the following steps: planning the design selection, conduct the experiments, collect observed data, proceed to analysis and interpretation of results. The focus is on providing both - a deep understanding of the problem under research and a powerful experimental process at a reduced cost. Mainly thanks to the possibility of allowing to separate variation sources, the importance of Experimental Design in Health Sciences is strongly recommended since long time. Particular attention has been devoted to Block Designs and more precisely to Balanced Incomplete Block Designs - in this case the relevance states from the fact that these designs allow testing simultaneously a number of treatments bigger than the block size. Our example refers to a possible study of inter reliability of the Parkinson disease, taking into account the UPDRS (Unified Parkinson's disease rating scale) in order to test if there are significant differences between the specialists who evaluate the patients performances. Statistical studies on this disease were described for example in Richards et al (1994), where the authors investigate the inter-rater Reliability of the Unified Parkinson's Disease Rating Scale Motor Examination. We consider a simulation of a practical situation in which the patients were observed by different specialists and the UPDRS on assessing the impact of Parkinson's disease in patients was observed. Assigning treatments to the subjects following a particular BIBD(9,24,8,3,2) structure, we illustrate that BIB Designs can be used as a powerful tool to solve emerging problems in this area. Once a structure with repeated blocks allows to have some block contrasts with minimum variance, see Oliveira et al. (2006), the design with cardinality 12 was selected for the example. R software was used for computations.

Assessing Tradeoffs between Observational and Experimental Designs for Charter School Research. Program on Education Policy and Governance Working Papers Series. PEPG 15-04

ERIC Educational Resources Information Center

Ackerman, Matthew; Egalite, Anna J.

2015-01-01

When lotteries are infeasible, researchers must rely on observational methods to estimate charter effectiveness at raising student test scores. Considerable attention has been paid to observational studies by the Stanford Center for Research on Education Outcomes (CREDO), which have analyzed charter performance in 27 states. However, the…

Cluster designs to assess the prevalence of acute malnutrition by lot quality assurance sampling: a validation study by computer simulation.

PubMed

Olives, Casey; Pagano, Marcello; Deitchler, Megan; Hedt, Bethany L; Egge, Kari; Valadez, Joseph J

2009-04-01

Traditional lot quality assurance sampling (LQAS) methods require simple random sampling to guarantee valid results. However, cluster sampling has been proposed to reduce the number of random starting points. This study uses simulations to examine the classification error of two such designs, a 67x3 (67 clusters of three observations) and a 33x6 (33 clusters of six observations) sampling scheme to assess the prevalence of global acute malnutrition (GAM). Further, we explore the use of a 67x3 sequential sampling scheme for LQAS classification of GAM prevalence. Results indicate that, for independent clusters with moderate intracluster correlation for the GAM outcome, the three sampling designs maintain approximate validity for LQAS analysis. Sequential sampling can substantially reduce the average sample size that is required for data collection. The presence of intercluster correlation can impact dramatically the classification error that is associated with LQAS analysis.

Space Suit Thermal Dynamics

NASA Technical Reports Server (NTRS)

Campbell, Anthony B.; Nair, Satish S.; Miles, John B.; Iovine, John V.; Lin, Chin H.

1998-01-01

The present NASA space suit (the Shuttle EMU) is a self-contained environmental control system, providing life support, environmental protection, earth-like mobility, and communications. This study considers the thermal dynamics of the space suit as they relate to astronaut thermal comfort control. A detailed dynamic lumped capacitance thermal model of the present space suit is used to analyze the thermal dynamics of the suit with observations verified using experimental and flight data. Prior to using the model to define performance characteristics and limitations for the space suit, the model is first evaluated and improved. This evaluation includes determining the effect of various model parameters on model performance and quantifying various temperature prediction errors in terms of heat transfer and heat storage. The observations from this study are being utilized in two future design efforts, automatic thermal comfort control design for the present space suit and design of future space suit systems for Space Station, Lunar, and Martian missions.

Recommended Values of Meteorological Factors to Be Considered in the Design of Aircraft Ice-Prevention Equipment

NASA Technical Reports Server (NTRS)

Jones, Alun R; Lewis, William

1949-01-01

Meteorological conditions conducive to aircraft icing are arranged in four classifications: three are associated with cloud structure and the fourth with freezing rain. The range of possible meteorological factors for each classification is discussed and specific values recommended for consideration in the design of ice-prevention equipment for aircraft are selected and tabulated. The values selected are based upon a study of the available observational data and theoretical considerations where observations are lacking. Recommendations for future research in the field are presented.

Measuring effectiveness of drugs in observational databanks: promises and perils

PubMed Central

Krishnan, Eswar; Fries, James F

2004-01-01

Observational databanks have inherent strengths and shortcomings. As in randomized controlled trials, poor design of these databanks can either exaggerate or reduce estimates of drug effectiveness and can limit generalizability. This commentary highlights selected aspects of study design, data collection and statistical analysis that can help overcome many of these inadequacies. An international metaRegister and a formal mechanism for standardizing and sharing drug data could help improve the utility of databanks. Medical journals have a vital role in enforcing a quality checklist that improves reporting. PMID:15059263

Computing Inter-Rater Reliability for Observational Data: An Overview and Tutorial

PubMed Central

Hallgren, Kevin A.

2012-01-01

Many research designs require the assessment of inter-rater reliability (IRR) to demonstrate consistency among observational ratings provided by multiple coders. However, many studies use incorrect statistical procedures, fail to fully report the information necessary to interpret their results, or do not address how IRR affects the power of their subsequent analyses for hypothesis testing. This paper provides an overview of methodological issues related to the assessment of IRR with a focus on study design, selection of appropriate statistics, and the computation, interpretation, and reporting of some commonly-used IRR statistics. Computational examples include SPSS and R syntax for computing Cohen’s kappa and intra-class correlations to assess IRR. PMID:22833776

Risk of bias and confounding of observational studies of Zika virus infection: A scoping review of research protocols

PubMed Central

Haby, Michelle M.; Martínez-Vega, Ruth; Pinzón-Flores, Carlos E.; Smith, Emma; Pinart, Mariona; Broutet, Nathalie; Becerra-Posada, Francisco; Aldighieri, Sylvain; Van Kerkhove, Maria D.

2017-01-01

Introduction Given the severity and impact of the current Zika virus (ZIKV) outbreak in the Americas, numerous countries have rushed to develop research studies to assess ZIKV and its potential health consequences. In an effort to ensure that studies are comprehensive, both internally and externally valid, and with reliable results, the World Health Organization, the Pan American Health Organization, Institut Pasteur, the networks of Fiocruz, the Consortia for the Standardization of Influenza Seroepidemiology (CONSISE) and the International Severe Acute Respiratory and Emerging Infection Consortium (ISARIC) have generated six standardized clinical and epidemiological research protocols and questionnaires to address key public health questions on ZIKV. Methods We conducted a systematic search of ongoing study protocols related to ZIKV research. We analyzed the content of protocols of 32 cohort studies and 13 case control studies for systematic bias that could produce erroneous results. Additionally we aimed to characterize the risks of bias and confounding in observational studies related to ZIKV and to propose ways to minimize them, including the use of six newly standardized research protocols. Results Observational studies of ZIKV face an array of challenges, including measurement of exposure and outcomes (microcephaly and Guillain-Barré Syndrome). Potential confounders need to be measured where known and controlled for in the analysis. Selection bias due to non-random selection is a significant issue, particularly in the case-control design, and losses to follow-up is equally important for the cohort design. Conclusion Observational research seeking to answer key questions on the ZIKV should consider these restrictions and take precautions to minimize bias in an effort to provide reliable and valid results. Utilization of the standardized research protocols developed by the WHO, PAHO, Institut Pasteur, and CONSISE will harmonize the key methodological aspects of each study design to minimize bias at different stages of the study. Biases need to be considered by researchers implementing the standardized protocols as well as by users of observational epidemiological studies of ZIKV. PMID:28686621

Effect of Booster Seat Design on Children’s Choice of Seating Positions During Naturalistic Riding

PubMed Central

Andersson, Marianne; Bohman, Katarina; Osvalder, Anna-Lisa

2010-01-01

The purpose of this naturalistic study was to investigate the effect of booster seat design on the choice of children’s seating positions during naturalistic riding. Data was collected through observations of children during in-vehicle riding by means of a film camera. The children were positioned in high back boosters in the rear seat while a parent drove the car. The study included two different booster designs: one with large head and torso side supports, and one with small head side supports and no torso side supports. Six children between three and six years of age participated in the study. Each child was observed in both boosters. The duration of the seating positions that each child assumed was quantified. The design with large side head supports resulted more often in seating positions without head and shoulder contact with the booster’s back. There was shoulder-to-booster back contact during an average of 45% of riding time in the seat with the large head side supports compared to 75% in the seat with the small head supports. The children in the study were seated with the head in front of the front edge of the head side supports more than half the time, in both boosters. Laterally, the children were almost constantly positioned between the side supports of the booster in both seats. The observed seating positions probably reduce the desired protective effect by the side supports in side impact, and may increase the probability of head impact with the vehicle interior in frontal impact. PMID:21050601

Advancing the science for active surveillance: rationale and design for the Observational Medical Outcomes Partnership.

PubMed

Stang, Paul E; Ryan, Patrick B; Racoosin, Judith A; Overhage, J Marc; Hartzema, Abraham G; Reich, Christian; Welebob, Emily; Scarnecchia, Thomas; Woodcock, Janet

2010-11-02

The U.S. Food and Drug Administration (FDA) Amendments Act of 2007 mandated that the FDA develop a system for using automated health care data to identify risks of marketed drugs and other medical products. The Observational Medical Outcomes Partnership is a public-private partnership among the FDA, academia, data owners, and the pharmaceutical industry that is responding to the need to advance the science of active medical product safety surveillance by using existing observational databases. The Observational Medical Outcomes Partnership's transparent, open innovation approach is designed to systematically and empirically study critical governance, data resource, and methodological issues and their interrelationships in establishing a viable national program of active drug safety surveillance by using observational data. This article describes the governance structure, data-access model, methods-testing approach, and technology development of this effort, as well as the work that has been initiated.

Characterization of spacecraft and environmental disturbances on a SmallSat

NASA Technical Reports Server (NTRS)

Johnson, Thomas A.; Nguyen, Dung Phu Chi; Cuda, Vince; Freesland, Doug

1994-01-01

The objective of this study is to model the on-orbit vibration environment encountered by a SmallSat. Vibration control issues are common to the Earth observing, imaging, and microgravity communities. A spacecraft may contain dozens of support systems and instruments each a potential source of vibration. The quality of payload data depends on constraining vibration so that parasitic disturbances do not affect the payload's pointing or microgravity requirement. In practice, payloads are designed incorporating existing flight hardware in many cases with nonspecific vibration performance. Thus, for the development of a payload, designers require a thorough knowledge of existing mechanical devices and their associated disturbance levels. This study evaluates a SmallSat mission and seeks to answer basic questions concerning on-orbit vibration. Payloads were considered from the Earth observing, microgravity, and imaging communities. Candidate payload requirements were matched to spacecraft bus resources of present day SmallSats. From the set of candidate payloads, the representative payload GLAS (Geoscience Laser Altimeter System) was selected. The requirements of GLAS were considered very stringent for the 150 - 500 kg class of payloads. Once the payload was selected, a generic SmallSat was designed in order to accommodate the payload requirements (weight, size, power, etc.). This study seeks to characterize the on-orbit vibration environment of a SmallSat designed for this type of mission and to determine whether a SmallSat can provide the precision pointing and jitter control required for earth observing payloads.

Design-Filter Selection for H2 Control of Microgravity Isolation Systems: A Single-Degree-of-Freedom Case Study

NASA Technical Reports Server (NTRS)

Hampton, R. David; Whorton, Mark S.

2000-01-01

Many microgravity space-science experiments require active vibration isolation, to attain suitably low levels of background acceleration for useful experimental results. The design of state-space controllers by optimal control methods requires judicious choices of frequency-weighting design filters. Kinematic coupling among states greatly clouds designer intuition in the choices of these filters, and the masking effects of the state observations cloud the process further. Recent research into the practical application of H2 synthesis methods to such problems, indicates that certain steps can lead to state frequency-weighting design-filter choices with substantially improved promise of usefulness, even in the face of these difficulties. In choosing these filters on the states, one considers their relationships to corresponding design filters on appropriate pseudo-sensitivity- and pseudo-complementary-sensitivity functions. This paper investigates the application of these considerations to a single-degree-of-freedom microgravity vibration-isolation test case. Significant observations that were noted during the design process are presented. along with explanations based on the existent theory for such problems.

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

USDA-ARS?s Scientific Manuscript database

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

The Impact of Visibility on Teamwork, Collaborative Communication, and Security in Emergency Departments: An Exploratory Study.

PubMed

Gharaveis, Arsalan; Hamilton, D Kirk; Pati, Debajyoti; Shepley, Mardelle

2017-01-01

The aim of this study was to examine the influence of visibility on teamwork, collaborative communication, and security issues in emergency departments (EDs). This research explored whether with high visibility in EDs, teamwork and collaborative communication can be improved while the security issues will be reduced. Visibility has been regarded as a critical design consideration and can be directly and considerably impacted by ED's physical design. Teamwork is one of the major related operational outcomes of visibility and involves nurses, support staff, and physicians. The collaborative communication in an ED is another important factor in the process of care delivery and affects efficiency and safety. Furthermore, security is a behavioral factor in ED designs, which includes all types of safety including staff safety, patient safety, and the safety of visitors and family members. This qualitative study investigated the impact of visibility on teamwork, collaborative communication, and security issues in the ED. One-on-one interviews and on-site observation sessions were conducted in a community hospital. Corresponding data analysis was implemented by using computer plan analysis, observation and interview content, and theme analyses. The findings of this exploratory study provided a framework to identify visibility as an influential factor in ED design. High levels of visibility impact productivity and efficiency of teamwork and communication and improve the chance of lowering security issues. The findings of this study also contribute to the general body of knowledge about the effect of physical design on teamwork, collaborative communication, and security.

1983 AFOSR/AFRPL Chemical Rocket Research Meeting, Abstracts and Agenda. Includes: Abstracts on Advanced Diagnostics of Reacting Flow, 28 February - 3 March 1983, Lancaster, California.

DTIC Science & Technology

1983-02-01

blow-off stability and fractional conversion was evaluated for design of an experimental study of these phenomena. The apparatus designed will be...the development of an array of experimental methods and test strategies designed to unravel a complex process that is very difficult to observe directly...this effort of lead field theoretic analysis as a design basis has made that possible. The experimental phase of the effort has three major

Solar power satellite system definition study. Part 2, volume 4: Microwave power transmission systems

NASA Technical Reports Server (NTRS)

1977-01-01

A slotted waveguide planar array was established as the baseline design for the spaceborne transmitter antenna. Key aspects of efficient energy conversion at both ends of the power transfer link were analyzed and optimized alternate approaches in the areas of antenna and tube design are discussed. An integrated design concept was developed which meets design requirements, observes structural and thermal constraints, exhibits good performance and was developed in adequate depth to permit cost estimating at the subsystem/component level.

Simulation based evaluation of the designs of the Advanced Gamma-ray Imageing System (AGIS)

NASA Astrophysics Data System (ADS)

Bugaev, Slava; Buckley, James; Digel, Seth; Funk, Stephen; Konopelko, Alex; Krawczynski, Henric; Lebohec, Steohan; Maier, Gernot; Vassiliev, Vladimir

2009-05-01

The AGIS project under design study, is a large array of imaging atmospheric Cherenkov telescopes for gamma-rays astronomy between 40GeV and 100 TeV. In this paper we present the ongoing simulation effort to model the considered design approaches as a function of the main parameters such as array geometry, telescope optics and camera design in such a way the gamma ray observation capabilities can be optimized against the overall project cost.

Toward rigorous idiographic research in prevention science: comparison between three analytic strategies for testing preventive intervention in very small samples.

PubMed

Ridenour, Ty A; Pineo, Thomas Z; Maldonado Molina, Mildred M; Hassmiller Lich, Kristen

2013-06-01

Psychosocial prevention research lacks evidence from intensive within-person lines of research to understand idiographic processes related to development and response to intervention. Such data could be used to fill gaps in the literature and expand the study design options for prevention researchers, including lower-cost yet rigorous studies (e.g., for program evaluations), pilot studies, designs to test programs for low prevalence outcomes, selective/indicated/adaptive intervention research, and understanding of differential response to programs. This study compared three competing analytic strategies designed for this type of research: autoregressive moving average, mixed model trajectory analysis, and P-technique. Illustrative time series data were from a pilot study of an intervention for nursing home residents with diabetes (N = 4) designed to improve control of blood glucose. A within-person, intermittent baseline design was used. Intervention effects were detected using each strategy for the aggregated sample and for individual patients. The P-technique model most closely replicated observed glucose levels. ARIMA and P-technique models were most similar in terms of estimated intervention effects and modeled glucose levels. However, ARIMA and P-technique also were more sensitive to missing data, outliers and number of observations. Statistical testing suggested that results generalize both to other persons as well as to idiographic, longitudinal processes. This study demonstrated the potential contributions of idiographic research in prevention science as well as the need for simulation studies to delineate the research circumstances when each analytic approach is optimal for deriving the correct parameter estimates.

Toward Rigorous Idiographic Research in Prevention Science: Comparison Between Three Analytic Strategies for Testing Preventive Intervention in Very Small Samples

PubMed Central

Pineo, Thomas Z.; Maldonado Molina, Mildred M.; Lich, Kristen Hassmiller

2013-01-01

Psychosocial prevention research lacks evidence from intensive within-person lines of research to understand idiographic processes related to development and response to intervention. Such data could be used to fill gaps in the literature and expand the study design options for prevention researchers, including lower-cost yet rigorous studies (e.g., for program evaluations), pilot studies, designs to test programs for low prevalence outcomes, selective/indicated/ adaptive intervention research, and understanding of differential response to programs. This study compared three competing analytic strategies designed for this type of research: autoregressive moving average, mixed model trajectory analysis, and P-technique. Illustrative time series data were from a pilot study of an intervention for nursing home residents with diabetes (N=4) designed to improve control of blood glucose. A within-person, intermittent baseline design was used. Intervention effects were detected using each strategy for the aggregated sample and for individual patients. The P-technique model most closely replicated observed glucose levels. ARIMA and P-technique models were most similar in terms of estimated intervention effects and modeled glucose levels. However, ARIMA and P-technique also were more sensitive to missing data, outliers and number of observations. Statistical testing suggested that results generalize both to other persons as well as to idiographic, longitudinal processes. This study demonstrated the potential contributions of idiographic research in prevention science as well as the need for simulation studies to delineate the research circumstances when each analytic approach is optimal for deriving the correct parameter estimates. PMID:23299558

Internal pilots for a class of linear mixed models with Gaussian and compound symmetric data

PubMed Central

Gurka, Matthew J.; Coffey, Christopher S.; Muller, Keith E.

2015-01-01

SUMMARY An internal pilot design uses interim sample size analysis, without interim data analysis, to adjust the final number of observations. The approach helps to choose a sample size sufficiently large (to achieve the statistical power desired), but not too large (which would waste money and time). We report on recent research in cerebral vascular tortuosity (curvature in three dimensions) which would benefit greatly from internal pilots due to uncertainty in the parameters of the covariance matrix used for study planning. Unfortunately, observations correlated across the four regions of the brain and small sample sizes preclude using existing methods. However, as in a wide range of medical imaging studies, tortuosity data have no missing or mistimed data, a factorial within-subject design, the same between-subject design for all responses, and a Gaussian distribution with compound symmetry. For such restricted models, we extend exact, small sample univariate methods for internal pilots to linear mixed models with any between-subject design (not just two groups). Planning a new tortuosity study illustrates how the new methods help to avoid sample sizes that are too small or too large while still controlling the type I error rate. PMID:17318914

Designing health promotion programs by watching the market.

PubMed

Gelb, B D; Bryant, J M

1992-03-01

More health care providers and payors are beginning to see health promotion programs as a significant tool for attracting patients, reducing costs, or both. To help design programs that take into account the values and lifestyles of the target group, naturalistic observation can be useful. The authors illustrate the approach in a study of pipeline workers that provided input for the design of nutrition and smoking cessation programs.

Rational design of a cyclin A fluorescent peptide sensor.

PubMed

Pazos, Elena; Pérez, Miguel; Gutiérrez-de-Terán, Hugo; Orzáez, Mar; Guevara, Tatiana; Mascareñas, José L; Vázquez, M Eugenio

2011-10-26

We report the design and development of a fluorescent sensor specifically designed to target cyclin A, a protein that plays a key role in the regulation of the cell cycle. Computational studies provide a molecular picture that explains the observed emission increase, suggesting that the 4-DMAP fluorophore in the peptide is protected from the bulk solvent when inserted into the hydrophobic binding groove of cyclin A.

The 2012 Ferrara seismic sequence: Regional crustal structure, earthquake sources, and seismic hazard

NASA Astrophysics Data System (ADS)

Malagnini, Luca; Herrmann, Robert B.; Munafò, Irene; Buttinelli, Mauro; Anselmi, Mario; Akinci, Aybige; Boschi, E.

2012-10-01

Inadequate seismic design codes can be dangerous, particularly when they underestimate the true hazard. In this study we use data from a sequence of moderate-sized earthquakes in northeast Italy to validate and test a regional wave propagation model which, in turn, is used to understand some weaknesses of the current design spectra. Our velocity model, while regionalized and somewhat ad hoc, is consistent with geophysical observations and the local geology. In the 0.02-0.1 Hz band, this model is validated by using it to calculate moment tensor solutions of 20 earthquakes (5.6 ≥ MW ≥ 3.2) in the 2012 Ferrara, Italy, seismic sequence. The seismic spectra observed for the relatively small main shock significantly exceeded the design spectra to be used in the area for critical structures. Observations and synthetics reveal that the ground motions are dominated by long-duration surface waves, which, apparently, the design codes do not adequately anticipate. In light of our results, the present seismic hazard assessment in the entire Pianura Padana, including the city of Milan, needs to be re-evaluated.

Evaluation of an Al-Ce alloy for laser additive manufacturing

DOE PAGES

Plotkowski, A.; Rios, O.; Sridharan, N.; ...

2016-12-27

Our present research in metal additive manufacturing (AM) focuses on designing processing parameters around existing alloys designed for traditional manufacturing. However, to maximize the benefits of AM, alloys should be designed to specifically take advantage of the unique thermal conditions of these processes. Furthermore, our study focuses on the development of a design methodology for alloys in AM, using a newly developed Al-Ce alloy as an initial case study. To evaluate the candidacy of this system for fusion based additive manufacturing, single-line laser melts were made on cast Al-12Ce plates using three different beam velocities (100, 200, and 300 mm/min).more » The microstructure was evaluated in the as-melted and heat treated conditions (24 hrs at 300°C). An extremely fine microstructure was observed within the weld pools, evolving from eutectic at the outer solid-liquid boundaries to a primary Al FCC dendritic/cellular structure nearer the melt-pool centerline. We rationalized the observed microstructures through the construction of a microstructure selection map for the Al-Ce binary system, which will be used to enable future alloy design. Interestingly, the heat treated samples exhibited no microstructural coarsening.« less

Effectiveness-implementation Hybrid Designs

PubMed Central

Curran, Geoffrey M.; Bauer, Mark; Mittman, Brian; Pyne, Jeffrey M.; Stetler, Cheryl

2013-01-01

Objectives This study proposes methods for blending design components of clinical effectiveness and implementation research. Such blending can provide benefits over pursuing these lines of research independently; for example, more rapid translational gains, more effective implementation strategies, and more useful information for decision makers. This study proposes a “hybrid effectiveness-implementation” typology, describes a rationale for their use, outlines the design decisions that must be faced, and provides several real-world examples. Results An effectiveness-implementation hybrid design is one that takes a dual focus a priori in assessing clinical effectiveness and implementation. We propose 3 hybrid types: (1) testing effects of a clinical intervention on relevant outcomes while observing and gathering information on implementation; (2) dual testing of clinical and implementation interventions/strategies; and (3) testing of an implementation strategy while observing and gathering information on the clinical intervention’s impact on relevant outcomes. Conclusions The hybrid typology proposed herein must be considered a construct still in evolution. Although traditional clinical effectiveness and implementation trials are likely to remain the most common approach to moving a clinical intervention through from efficacy research to public health impact, judicious use of the proposed hybrid designs could speed the translation of research findings into routine practice. PMID:22310560

Design and evaluation of a kitchen for persons with visual impairments.

PubMed

Kutintara, Benjamas; Somboon, Pornpun; Buasri, Virajada; Srettananurak, Metinee; Jedeeyod, Piyanooch; Pornpratoom, Kittikan; Iam-cham, Veraya

2013-03-01

Visually impaired people need skills on daily living, such as cooking, and Ratchasuda College offers independent living training for them. In order to fulfill their needs, a suitable kitchen should be designed with the consideration of their limitations. The objective of this study was to design and evaluate a kitchen for persons with visual impairments. Before designing the kitchen, interviews and an observation were carried out to obtain information on the needs of blind and low vision persons. Consequently, a kitchen model was developed, and it was evaluated by 10 persons with visual impairments. After the design improvement, the kitchen was built and has been routinely used for training persons with visual impairments to prepare meals. Finally, a post-occupancy evaluation of the kitchen was conducted by observing and interviewing both trainers and those with visual impairments during the food preparation training. The results of the study indicated that kitchens for persons with visual impairments should have safety and usability features. The results of the post-occupancy evaluation showed that those who attended cooking courses were able to cook safely in the kitchen. However, the kitchen still had limitations in some features.

Optical MEMS for earth observation payloads

NASA Astrophysics Data System (ADS)

Rodrigues, B.; Lobb, D. R.; Freire, M.

2017-11-01

An ESA study has been taken by Lusospace Ltd and Surrey Satellite Techonoly Ltd (SSTL) into the use of optical Micro Eletro-Mechanical Systems (MEMS) for earth Observation. A review and analysis was undertaken of the Micro-Optical Electro-Mechanical Systems (MOEMS) available in the market with potential application in systems for Earth Observation. A summary of this review will be presented. Following the review two space-instrument design concepts were selected for more detailed analysis. The first was the use of a MEMS device to remove cloud from Earth images. The concept is potentially of interest for any mission using imaging spectrometers. A spectrometer concept was selected and detailed design aspects and benefits evaluated. The second concept developed uses MEMS devices to control the width of entrance slits of spectrometers, to provide variable spectral resolution. This paper will present a summary of the results of the study.

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

PubMed

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

2015-11-01

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

Coordination and management of multicenter clinical studies in trauma: Experience from the PRospective Observational Multicenter Major Trauma Transfusion (PROMMTT) Study.

PubMed

Rahbar, Mohammad H; Fox, Erin E; del Junco, Deborah J; Cotton, Bryan A; Podbielski, Jeanette M; Matijevic, Nena; Cohen, Mitchell J; Schreiber, Martin A; Zhang, Jiajie; Mirhaji, Parsa; Duran, Sarah J; Reynolds, Robert J; Benjamin-Garner, Ruby; Holcomb, John B

2012-04-01

Early death due to hemorrhage is a major consequence of traumatic injury. Transfusion practices differ among hospitals and it is unknown which transfusion practices improve survival. This report describes the experience of the PRospective Observational Multicenter Major Trauma Transfusion (PROMMTT) Study Data Coordination Center in designing and coordinating a study to examine transfusion practices at ten Level 1 trauma centers in the US. PROMMTT was a multisite prospective observational study of severely injured transfused trauma patients. The clinical sites collected real-time information on the timing and amounts of blood product infusions as well as colloids and crystalloids, vital signs, initial diagnostic and clinical laboratory tests, life saving interventions and other clinical care data. Between July 2009 and October 2010, PROMMTT screened 12,561 trauma admissions and enrolled 1245 patients who received one or more blood transfusions within 6h of Emergency Department (ED) admission. A total of 297 massive transfusions were observed over the course of the study at a combined rate of 5.0 massive transfusion patients/week. PROMMTT is the first multisite study to collect real-time prospective data on trauma patients requiring transfusion. Support from the Department of Defense and collaborative expertise from the ten participating centers helped to demonstrate the feasibility of prospective trauma transfusion studies. The observational data collected from this study will be an invaluable resource for research in trauma surgery and it will guide the design and conduct of future randomized trials. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Media Coverage, Journal Press Releases and Editorials Associated with Randomized and Observational Studies in High-Impact Medical Journals: A Cohort Study.

PubMed

Wang, Michael T M; Bolland, Mark J; Gamble, Greg; Grey, Andrew

2015-01-01

Publication of clinical research findings in prominent journals influences health beliefs and medical practice, in part by engendering news coverage. Randomized controlled trials (RCTs) should be most influential in guiding clinical practice. We determined whether study design of clinical research published in high-impact journals influences media coverage. We compared the incidence and amount of media coverage of RCTs with that of observational studies published in the top 7 medical journals between 1 January 2013 and 31 March 2013. We specifically assessed media coverage of the most rigorous RCTs, those with >1000 participants that reported 'hard' outcomes. There was no difference between RCTs and observational studies in coverage by major newspapers or news agencies, or in total number of news stories generated (all P>0.63). Large RCTs reporting 'hard' outcomes did not generate more news coverage than small RCTs that reported surrogate outcomes and observational studies (all P>0.32). RCTs were more likely than observational studies to attract a journal editorial (70% vs 46%, P = 0.003), but less likely to be the subject of a journal press release (17% vs 50%, P<0.001). Large RCTs that reported 'hard' outcomes did not attract an editorial more frequently than other studies (61% vs 58%, P>0.99), nor were they more likely to be the subject of a journal press release (14% vs 38%, P = 0.14). The design of clinical studies whose results are published in high-impact medical journals is not associated with the likelihood or amount of ensuing news coverage.

Coordination and management of multicenter clinical studies in trauma: Experience from the PRospective Observational Multicenter Major Trauma Transfusion (PROMMTT) Study

PubMed Central

Rahbar, Mohammad H.; Fox, Erin E.; del Junco, Deborah J.; Cotton, Bryan A.; Podbielski, Jeanette M.; Matijevic, Nena; Cohen, Mitchell J.; Schreiber, Martin A.; Zhang, Jiajie; Mirhaji, Parsa; Duran, Sarah; Reynolds, Robert J.; Benjamin-Garner, Ruby; Holcomb, John B.

2011-01-01

Aim Early death due to hemorrhage is a major consequence of traumatic injury. Transfusion practices differ among hospitals and it is unknown which transfusion practices improve survival. This report describes the experience of the PRospective Observational Multicenter Major Trauma Transfusion (PROMMTT) Study Data Coordination Center in designing and coordinating a study to examine transfusion practices at ten Level 1 trauma centers in the U.S. Methods PROMMTT was a multisite prospective observational study of severely injured transfused trauma patients. The clinical sites collected real-time information on the timing and amounts of blood product infusions as well as colloids and crystalloids, vital signs, initial diagnostic and clinical laboratory tests, life saving interventions and other clinical care data. Results Between July 2009 and October 2010, PROMMTT screened 12,561 trauma admissions and enrolled 1,245 patients who received one or more blood transfusions within 6 hours of ED admission. A total of 297 massive transfusions were observed over the course of the study at a combined rate of 5.0 massive transfusion patients/week. Conclusion PROMMTT is the first multisite study to collect real-time prospective data on trauma patients requiring transfusion. Support from the Department of Defense and collaborative expertise from the ten participating centers helped to demonstrate the feasibility of prospective trauma transfusion studies. The observational data collected from this study will be an invaluable resource for research in trauma surgery and it will guide the design and conduct of future randomized trials. PMID:22001613

No Need to Wait for Superman: A Case Study of One Unique High School

ERIC Educational Resources Information Center

Ratcliff, N. J.; Jones, C. R.; Costner, R. H.; Knight, C.; Disney, G.; Savage-Davis, E.; Sheehan, H.; Hunt, G. H.

2012-01-01

Based on a theoretical model developed by Schlechty, this case study focuses on a small high school, located on a college campus and designed to address the educational needs of gifted 9th- through 12th-grade students. Eight teachers who taught 9th- and 12th-grade classes and their 60 students were observed. Each teacher was observed during six…

Geosynchronous Microwave Atmospheric Sounding Radiometer (MASR) feasibility studies. Volume 1: Management summary

NASA Technical Reports Server (NTRS)

1978-01-01

The mission of the microwave atmospheric sounding radiometer (MASR) is to collect data to aid in the observation and prediction of severe storms. The geosynchronous orbit allows the continuous atmospheric measurement needed to resolve mesoscale dynamics. The instrument may operate in conjunction with this document, Volume 1 - Management, which summarizes the highlights of final reports on both the radiometer instrument and antenna studies. The radiometer instrument summary includes a synopsis of Volume 2 - Radiometer Receiver Feasibility, including design, recommended configuration, performance estimates, and weight and power estimates. The summary of the antenna study includes a synopsis of Volume 3 - Antenna Feasibility, including preliminary design tradeoffs, performance of selected design, and details of the mechanical/thermal design.

Designing a Pediatric Study for an Antimalarial Drug by Using Information from Adults

PubMed Central

Jullien, Vincent; Samson, Adeline; Guedj, Jérémie; Kiechel, Jean-René; Zohar, Sarah; Comets, Emmanuelle

2015-01-01

The objectives of this study were to design a pharmacokinetic (PK) study by using information about adults and evaluate the robustness of the recommended design through a case study of mefloquine. PK data about adults and children were available from two different randomized studies of the treatment of malaria with the same artesunate-mefloquine combination regimen. A recommended design for pediatric studies of mefloquine was optimized on the basis of an extrapolated model built from adult data through the following approach. (i) An adult PK model was built, and parameters were estimated by using the stochastic approximation expectation-maximization algorithm. (ii) Pediatric PK parameters were then obtained by adding allometry and maturation to the adult model. (iii) A D-optimal design for children was obtained with PFIM by assuming the extrapolated design. Finally, the robustness of the recommended design was evaluated in terms of the relative bias and relative standard errors (RSE) of the parameters in a simulation study with four different models and was compared to the empirical design used for the pediatric study. Combining PK modeling, extrapolation, and design optimization led to a design for children with five sampling times. PK parameters were well estimated by this design with few RSE. Although the extrapolated model did not predict the observed mefloquine concentrations in children very accurately, it allowed precise and unbiased estimates across various model assumptions, contrary to the empirical design. Using information from adult studies combined with allometry and maturation can help provide robust designs for pediatric studies. PMID:26711749

Study on the Preliminary Design of ARGO-M Operation System

NASA Astrophysics Data System (ADS)

Seo, Yoon-Kyung; Lim, Hyung-Chul; Rew, Dong-Young; Jo, Jung Hyun; Park, Jong-Uk; Park, Eun-Seo; Park, Jang-Hyun

2010-12-01

Korea Astronomy and Space Science Institute has been developing one mobile satellite laser ranging system named as accurate ranging system for geodetic observation-mobile (ARGO-M). Preliminary design of ARGO-M operation system (AOS) which is one of the ARGO-M subsystems was completed in 2009. Preliminary design results are applied to the following development phase by performing detailed design with analysis of pre-defined requirements and analysis of the derived specifications. This paper addresses the preliminary design of the whole AOS. The design results in operation and control part which is a key part in the operation system are described in detail. Analysis results of the interface between operation-supporting hardware and the control computer are summarized, which is necessary in defining the requirements for the operation-supporting hardware. Results of this study are expected to be used in the critical design phase to finalize the design process.

Vitamin K’s role in age-related bone loss: A critical review

USDA-ARS?s Scientific Manuscript database

The protective role of vitamin K in age-related bone loss continues to be controversial. The results of observational analyses are inconsistent with respect to associations between vitamin K status and bone, which arguably may be related to the limitations of observational study designs and analyt...

Improving the Efficiency of Virtual Reality Training by Integrating Partly Observational Learning

ERIC Educational Resources Information Center

Yuviler-Gavish, Nirit; Rodríguez, Jorge; Gutiérrez, Teresa; Sánchez, Emilio; Casado, Sara

2014-01-01

The current study hypothesized that integrating partly observational learning into virtual reality training systems (VRTS) can enhance training efficiency for procedural tasks. A common approach in designing VRTS is the enactive approach, which stresses the importance of physical actions within the environment to enhance perception and improve…

Administrators' Perceptions Regarding the Effectiveness of the Teacher Observation Evaluation System

ERIC Educational Resources Information Center

Williams, Kathleen Riley

2015-01-01

This phenomenological narrative study was designed to explore public school administrators' perceptions regarding Louisiana's Compass teacher observation evaluation system as a method for assessing teacher performance. Participants were administrators with at least two years of experience as a public school administrator at the secondary level,…

Trends in Classroom Observation Scores

ERIC Educational Resources Information Center

Casabianca, Jodi M.; Lockwood, J. R.; McCaffrey, Daniel F.

2015-01-01

Observations and ratings of classroom teaching and interactions collected over time are susceptible to trends in both the quality of instruction and rater behavior. These trends have potential implications for inferences about teaching and for study design. We use scores on the Classroom Assessment Scoring System-Secondary (CLASS-S) protocol from…

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

PubMed

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

2017-07-01

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

Software sensors for bioprocesses.

PubMed

Bogaerts, Ph; Vande Wouwer, A

2003-10-01

State estimation is a significant problem in biotechnological processes, due to the general lack of hardware sensor measurements of the variables describing the process dynamics. The objective of this paper is to review a number of software sensor design methods, including extended Kalman filters, receding-horizon observers, asymptotic observers, and hybrid observers, which can be efficiently applied to bioprocesses. These several methods are illustrated with simulation and real-life case studies.

Sliding mode disturbance observer-enhanced adaptive control for the air-breathing hypersonic flight vehicle

NASA Astrophysics Data System (ADS)

An, Hao; Wang, Changhong; Fidan, Baris

2017-10-01

This paper presents a backstepping procedure to design an adaptive controller for the air-breathing hypersonic flight vehicle (AHFV) subject to external disturbances and actuator saturations. In each step, a sliding mode exact disturbance observer (SMEDO) is exploited to exactly estimate the lumped disturbance in finite time. Specific dynamics are introduced to handle the possible actuator saturations. Based on SMEDO and introduced dynamics, an adaptive control law is designed, along with the consideration on ;explosion of complexity; in backstepping design. The developed controller is equipped with fast disturbance rejection and great capability to accommodate the saturated actuators, which also lead to a wider application scope. A simulation study is provided to show the effectiveness and superiority of the proposed controller.

LWS design replacement study: Optimum design and tradeoff analysis

NASA Technical Reports Server (NTRS)

1973-01-01

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

Landmarks selection in street map design

NASA Astrophysics Data System (ADS)

Kao, C. J.

2014-02-01

In Taiwan many electrical maps present their landmarks according to the category of the feature, a designer short of knowledge about mental representation of space, can cause the map to lose its communication effects. To resolve this map design problem, in this research through long-term memory recall, navigation and observation, and short-term memory processing 111 participants were asked to select the proper landmark from study area. The results reveal that in Taiwan convenience stores are the most popular local landmark in rural and urban areas. Their commercial signs have a unique design and bright color. Contrasted to their background, this makes the convenience store a salient feature. This study also developed a rule to assess the priority of the landmarks to design them in different scale maps.

Ultraviolet Studies of Interstellar Molecular Hydrogen

NASA Astrophysics Data System (ADS)

Sarlin, Scott Peter

1998-12-01

This work covers the design and conduct of two experiments designed to observe molecular hydrogen in the interstellar medium. The first experiment was intended to directly observe the ratio between H2 and CO column densities in translucent molecular clouds in order to calibrate CO radio maps and observations of this galaxy and others. H2 cannot be directly observed from the ground under ordinary circumstances, so a novel high resolution (30,000 λΔλ) ultraviolet (UV) spectrograph was designed and built to observe it in absorption in the spectra of a distant star (HD 206267). The instrument operated properly, but the target was not acquired and the sounding rocket's parachute did not deploy, destroying the instrument. The second experiment was to observe H2 absorption towards γ Cassiopeia at very high spectral resolution (-240,000 λΔλ) with a space shuttle experiment called IMAPS. Despite several problems, including a dramatic loss in sensitivity, H2 absorption lines from J=0, 1, 2, and 3 were detected and measured. In conjunction with published atomic line observations, this gas was determined to be from a very small, thermally dominated cloud embedded in a larger H I region. The lack of higher J-state detections preclude a definitive statement concerning the radiation field, although the data point towards limited UV excitation. Future directions for instrument development are then briefly discussed.

Mathematical Practices in a Technological Setting: A Design Research Experiment for Teaching Circle Properties

ERIC Educational Resources Information Center

Akyuz, Didem

2016-01-01

This article documents the classroom mathematical practices observed in a collegiate level teacher education course related to the circle topic. The course, which was prepared as design research, utilized a dynamic geometry environment which influenced the type and nature of the evolved mathematical practices. The study uses emergent perspective…

Towards a Taxonomy of Intergenerational Knowledge Transfer Practices: Insights from an International Comparison (Germany-Quebec)

ERIC Educational Resources Information Center

Kuyken, Kerstin; Ebrahimi, Mehran; Saives, Anne-Laure

2018-01-01

Purpose: This paper aims to develop a better understanding of intergenerational knowledge transfer (IKT) practices by adopting a context-related and comparative perspective. Design/methodology/approach: A qualitative case study design involving 83 interviews and non-participative observation in German and Quebec organizations has been chosen.…

Culturally Relevant Design Practices: A Case Study for Designing Interactive Algebra Lessons for Urban Youth

ERIC Educational Resources Information Center

Gilbert, Juan E.; Eugene, Wanda; Swanier, Cheryl; Arbuthnot, Keena; Hood, Stafford; Grant, Michael McKenzie; West, Melanie L.

2008-01-01

When culture is integrated into the mathematics classroom, it improves students' academic achievement, helps move classrooms towards an equitable learning environment, helps students to have positive beliefs about mathematics, and integrates mathematics with other disciplines. Moreover, if you observe today's kids, the use of video games in their…

Educative Curriculum Materials: Uptake, Impact, and Implications for Research and Design

ERIC Educational Resources Information Center

Davis, Elizabeth A.; Palincsar, Annemarie Sullivan; Smith, P. Sean; Arias, Anna Maria; Kademian, Sylvie M.

2017-01-01

The authors synthesize the findings of a research project to extend what is known about educative curriculum materials, or curriculum materials designed with the intent of supporting teacher learning as well as student learning. Drawing on a three-year program of research, including several close observational case studies and a large-scale…

Nanohole Arrays of Mixed Designs and Microwriting for Simultaneous and Multiple Protein Binding Studies

PubMed Central

Ji, Jin; Yang, Jiun-Chan; Larson, Dale N.

2009-01-01

We demonstrate using nanohole arrays of mixed designs and a microwriting process based on dip-pen nanolithography to monitor multiple, different protein binding events simultaneously in real time based on the intensity of Extraordinary Optical Transmission of nanohole arrays. The microwriting process and small footprint of the individual nanohole arrays enabled us to observe different binding events located only 16μm apart, achieving high spatial resolution. We also present a novel concept that incorporates nanohole arrays of different designs to improve confidence and accuracy of binding studies. For proof of concept, two types of nanohole arrays, designed to exhibit opposite responses to protein bindings, were fabricated on one transducer. Initial studies indicate that the mixed designs could help to screen out artifacts such as protein intrinsic signals, providing improved accuracy of binding interpretation. PMID:19297143

Model medication management process in Australian nursing homes using business process modeling.

PubMed

Qian, Siyu; Yu, Ping

2013-01-01

One of the reasons for end user avoidance or rejection to use health information systems is poor alignment of the system with healthcare workflow, likely causing by system designers' lack of thorough understanding about healthcare process. Therefore, understanding the healthcare workflow is the essential first step for the design of optimal technologies that will enable care staff to complete the intended tasks faster and better. The often use of multiple or "high risk" medicines by older people in nursing homes has the potential to increase medication error rate. To facilitate the design of information systems with most potential to improve patient safety, this study aims to understand medication management process in nursing homes using business process modeling method. The paper presents study design and preliminary findings from interviewing two registered nurses, who were team leaders in two nursing homes. Although there were subtle differences in medication management between the two homes, major medication management activities were similar. Further field observation will be conducted. Based on the data collected from observations, an as-is process model for medication management will be developed.

Randomized Trials Built on Sand: Examples from COPD, Hormone Therapy, and Cancer

PubMed Central

Suissa, Samy

2012-01-01

The randomized controlled trial is the fundamental study design to evaluate the effectiveness of medications and receive regulatory approval. Observational studies, on the other hand, are essential to address post-marketing drug safety issues but have also been used to uncover new indications or new benefits for already marketed drugs. Hormone replacement therapy (HRT) for instance, effective for menopausal symptoms, was reported in several observational studies during the 1980s and 1990s to also significantly reduce the incidence of coronary heart disease. This claim was refuted in 2002 by the large-scale Women’s Health Initiative randomized trial. An example of a new indication for an old drug is that of metformin, an anti-diabetic medication, which is being hailed as a potential anti-cancer agent, primarily on the basis of several recent observational studies that reported impressive reductions in cancer incidence and mortality with its use. These observational studies have now sparked the conduct of large-scale randomized controlled trials currently ongoing in cancer. We show in this paper that the spectacular effects on new indications or new outcomes reported in many observational studies in chronic obstructive pulmonary disease (COPD), HRT, and cancer are the result of time-related biases, such as immortal time bias, that tend to seriously exaggerate the benefits of a drug and that eventually disappear with the proper statistical analysis. In all, while observational studies are central to assess the effects of drugs, their proper design and analysis are essential to avoid bias. The scientific evidence on the potential beneficial effects in new indications of existing drugs will need to be more carefully assessed before embarking on long and expensive unsubstantiated trials. PMID:23908838

Trust Me: Design Patterns for Constructing Trustworthy Trust Indicators

DTIC Science & Technology

2009-04-01

contacted by Microsoft to participate in user studies, and screened out participants who either did not use Hotmail for their email or did not use IE as...purpose. We decided to tell participants that we were working on improvements for Windows Live Hotmail , and therefore we would be observing them interacting...minutes. At this point, the experimenter observed them log into their Hotmail accounts, and then left the room to observe them from our observation

Earth Observatory Satellite system definition study. Report 7: EOS system definition report

NASA Technical Reports Server (NTRS)

1974-01-01

The Earth Observatory Satellite (EOS) study is summarized to show the modular design of a general purpose spacecraft, a mission peculiar segment which performs the EOS-A mission, an Operations Control Center, a Data Processing Facility, and a design for Low Cost Readout Stations. The study verified the practicality and feasibility of the modularized spacecraft with the capability of supporting many missions in the Earth Observation spectrum. The various subjects considered in the summary are: (1) orbit/launch vehicle tradeoff studies and recommendations, (2) instrument constraints and interfaces, (3) design/cost tradeoff and recommendations, (4) low cost management approach and recommendations, (5) baseline system description and specifications, and (6) space shuttle utilization and interfaces.

Design to Improve Visibility: Impact of Corridor Width and Unit Shape.

PubMed

Hadi, Khatereh; Zimring, Craig

2016-07-01

This study analyzes 10 intensive care units (ICUs) to understand the associations between design features of space layout and nurse-to-patient visibility parameters. Previous studies have explored how different hospital units vary in their visibility relations and how such varied visibility relations result in different nurse behaviors toward patients. However, more limited research has examined the specific design attributes of the layouts that determine the varied visibility relations in the unit. Changes in size, geometry, or other attributes of design elements in nursing units, which might affect patient observation opportunities, require more research. This article reviews the literature to indicate evidence for the impact of hospital unit design on nurse/patient visibility relations and to identify design parameters shown to affect visibility. It further focuses on 10 ICUs to investigate how different layouts diverge regarding their visibility relations using a set of metrics developed by other researchers. Shape geometry and corridor width, as two selected design features, are compared. Corridor width and shape characteristics of ICUs are positively correlated with visibility. Results suggest that floor plans, which are repeatedly broken down into smaller convex (higher convex fragmentation values), or units, which have longer distances between their rooms or between their two opposite ends (longer relative grid distances), might have lower visibility levels across the unit. The findings of this study also suggest that wider corridors positively affect visibility of patient rooms. Changes in overall shape configuration and corridor width of nursing units may have important effects on patient observation and monitoring opportunities. © The Author(s) 2016.

The Multisensory Environment (MSE) in Dementia Care: Examining Its Role and Quality From a User Perspective.

PubMed

Collier, Lesley; Jakob, Anke

2017-10-01

Multisensory environments (MSEs) for people with dementia have been available over 20 years but are used in an ad hoc manner using an eclectic range of equipment. Care homes have endeavored to utilize this approach but have struggled to find a design and approach that works for this setting. Study aims were to appraise the evolving concept of MSEs from a user perspective, to study the aesthetic and functional qualities, to identify barriers to staff engagement with a sensory environment approach, and to identify design criteria to improve the potential of MSE for people with dementia. Data were collected from 16 care homes with experience of MSE using ethnographic methods, incorporating semi-structured interviews, and observations of MSE design. Analysis was undertaken using descriptive statistics and thematic analysis. Observations revealed equipment that predominantly stimulated vision and touch. Thematic analysis of the semi-structured interviews revealed six themes: not knowing what to do in the room, good for people in the later stages of the disease, reduces anxiety, it's a good activity, design and setting up of the space, and including relatives and care staff. Few MSEs in care homes are designed to meet needs of people with dementia, and staff receive little training in how to facilitate sessions. As such, MSEs are often underused despite perceived benefits. Results of this study have been used to identify the design principles that have been reviewed by relevant stakeholders.

An investigation of the artifacts, outcomes, and processes of constructing computer games about environmental science in a fifth grade science classroom

NASA Astrophysics Data System (ADS)

Baytak, Ahmet

Among educational researchers and practitioners, there is a growing interest in employing computer games for pedagogical purposes. The present research integrated a technology education class and a science class where 5 th graders learned about environmental issues by designing games that involved environmental concepts. The purposes of this study were to investigate how designing computer games affected the development of students' environmental knowledge, programming knowledge, environmental awareness and interest in computers. It also explored the nature of the artifacts developed and the types of knowledge represented therein. A case study (Yin, 2003) was employed within the context of a 5 th grade elementary science classroom. Fifth graders designed computer games about environmental issues to present to 2nd graders by using Scratch software. The analysis of this study was based on multiple data sources: students' pre- and post-test scores on environmental awareness, their environmental knowledge, their interest in computer science, and their game design. Included in the analyses were also data from students' computer games, participant observations, and structured interviews. The results of the study showed that students were able to successfully design functional games that represented their understanding of environment, even though the gain between pre- and post-environmental knowledge test and environmental awareness survey were minimal. The findings indicate that all students were able to use various game characteristics and programming concepts, but their prior experience with the design software affected their representations. The analyses of the interview transcriptions and games show that students improved their programming skills and that they wanted to do similar projects for other subject areas in the future. Observations showed that game design appeared to lead to knowledge-building, interaction and collaboration among students. This, in turn, encouraged students to test and improve their designs. Sharing the games, it was found, has both positive and negative effects on the students' game design process and the representation of students' understandings of the domain subject.

Using simulation to improve wildlife surveys: Wintering mallards in Mississippi, USA

USGS Publications Warehouse

Pearse, A.T.; Reinecke, K.J.; Dinsmore, S.J.; Kaminski, R.M.

2009-01-01

Wildlife conservation plans generally require reliable data about population abundance and density. Aerial surveys often can provide these data; however, associated costs necessitate designing and conducting surveys efficiently. We developed methods to simulate population distributions of mallards (Anas platyrhynchos) wintering in western Mississippi, USA, by combining bird observations from three previous strip-transect surveys and habitat data from three sets of satellite images representing conditions when surveys were conducted. For each simulated population distribution, we compared 12 primary survey designs and two secondary design options by using coefficients of variation (CV) of population indices as the primary criterion for assessing survey performance. In all, 3 of the 12 primary designs provided the best precision (CV???11.7%) and performed equally well (WR08082E1d.gif diff???0.6%). Features of the designs that provided the largest gains in precision were optimal allocation of sample effort among strata and configuring the study area into five rather than four strata, to more precisely estimate mallard indices in areas of consistently high density. Of the two secondary design options, we found including a second observer to double the size of strip transects increased precision or decreased costs, whereas ratio estimation using auxiliary habitat data from satellite images did not increase precision appreciably. We recommend future surveys of mallard populations in our study area use the strata we developed, optimally allocate samples among strata, employ PPS or EPS sampling, and include two observers when qualified staff are available. More generally, the methods we developed to simulate population distributions from prior survey data provide a cost-effective method to assess performance of alternative wildlife surveys critical to informing management decisions, and could be extended to account for effects of detectability on estimates of true abundance. ?? 2009 CSIRO.

A survey of student opinions on ethical design standards in Taiwan.

PubMed

Lee, Yingying; You, Manlai; Yang, Ming-Ying

2015-04-01

Design ethics has been offered as a course in undergraduate design programs in Taiwan for over a decade, but research on teaching design ethics and the results of teaching these courses is scant. We conducted two tests to examine (1) the effect of an ethics course, and (2) the differences among the effects of design department, gender, and study year on student opinions regarding ethical design standards (EDSs) at the National Yunlin University of Science and Technology (YunTech) in Taiwan. The participants comprised 934 undergraduates (660 women and 274 men) from the five design departments at YunTech's College of Design from Years 1-4. The results confirmed the effect of an ethics course on student EDS opinions. In addition, we observed significant variations among students according to design departments, suggesting that the characteristics of the design departments also affected students' EDS opinions. The results indicated that gender did not significantly affect design students' EDS opinions; however, students in their early years of study produced higher scores than those in their advanced years of study did, based on the six EDS opinions. The implications of these results for teaching design ethics and future research are discussed in this paper.

Local Scale Radiobrightness Modeling During the Intensive Observing Period-4 of the Cold Land Processes Experiment-1

NASA Astrophysics Data System (ADS)

Kim, E.; Tedesco, M.; de Roo, R.; England, A. W.; Gu, H.; Pham, H.; Boprie, D.; Graf, T.; Koike, T.; Armstrong, R.; Brodzik, M.; Hardy, J.; Cline, D.

2004-12-01

The NASA Cold Land Processes Field Experiment (CLPX-1) was designed to provide microwave remote sensing observations and ground truth for studies of snow and frozen ground remote sensing, particularly issues related to scaling. CLPX-1 was conducted in 2002 and 2003 in Colorado, USA. One of the goals of the experiment was to test the capabilities of microwave emission models at different scales. Initial forward model validation work has concentrated on the Local-Scale Observation Site (LSOS), a 0.8~ha study site consisting of open meadows separated by trees where the most detailed measurements were made of snow depth and temperature, density, and grain size profiles. Results obtained in the case of the 3rd Intensive Observing Period (IOP3) period (February, 2003, dry snow) suggest that a model based on Dense Medium Radiative Transfer (DMRT) theory is able to model the recorded brightness temperatures using snow parameters derived from field measurements. This paper focuses on the ability of forward DMRT modelling, combined with snowpack measurements, to reproduce the radiobrightness signatures observed by the University of Michigan's Truck-Mounted Radiometer System (TMRS) at 19 and 37~GHz during the 4th IOP (IOP4) in March, 2003. Unlike in IOP3, conditions during IOP4 include both wet and dry periods, providing a valuable test of DMRT model performance. In addition, a comparison will be made for the one day of coincident observations by the University of Tokyo's Ground-Based Microwave Radiometer-7 (GBMR-7) and the TMRS. The plot-scale study in this paper establishes a baseline of DMRT performance for later studies at successively larger scales. And these scaling studies will help guide the choice of future snow retrieval algorithms and the design of future Cold Lands observing systems.

Effect of strong-column weak-beam design provision on the seismic fragility of RC frame buildings

NASA Astrophysics Data System (ADS)

Surana, Mitesh; Singh, Yogendra; Lang, Dominik H.

2018-04-01

Incremental dynamic analyses are conducted for a suite of low- and mid-rise reinforced-concrete special moment-resisting frame buildings. Buildings non-conforming and conforming to the strong-column weak-beam (SCWB) design criterion are considered. These buildings are designed for the two most severe seismic zones in India (i.e., zone IV and zone V) following the provisions of Indian Standards. It is observed that buildings non-conforming to the SCWB design criterion lead to an undesirable column failure collapse mechanism. Although yielding of columns cannot be avoided, even for buildings conforming to a SCWB ratio of 1.4, the observed collapse mechanism changes to a beam failure mechanism. This change in collapse mechanism leads to a significant increase in the building's global ductility capacity, and thereby in collapse capacity. The fragility analysis study of the considered buildings suggests that considering the SCWB design criterion leads to a significant reduction in collapse probability, particularly in the case of mid-rise buildings.

Considerations for Observational Research Using Large Data Sets in Radiation Oncology

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

Jagsi, Reshma, E-mail: rjagsi@med.umich.edu; Bekelman, Justin E.; Chen, Aileen

The radiation oncology community has witnessed growing interest in observational research conducted using large-scale data sources such as registries and claims-based data sets. With the growing emphasis on observational analyses in health care, the radiation oncology community must possess a sophisticated understanding of the methodological considerations of such studies in order to evaluate evidence appropriately to guide practice and policy. Because observational research has unique features that distinguish it from clinical trials and other forms of traditional radiation oncology research, the International Journal of Radiation Oncology, Biology, Physics assembled a panel of experts in health services research to provide a concisemore » and well-referenced review, intended to be informative for the lay reader, as well as for scholars who wish to embark on such research without prior experience. This review begins by discussing the types of research questions relevant to radiation oncology that large-scale databases may help illuminate. It then describes major potential data sources for such endeavors, including information regarding access and insights regarding the strengths and limitations of each. Finally, it provides guidance regarding the analytical challenges that observational studies must confront, along with discussion of the techniques that have been developed to help minimize the impact of certain common analytical issues in observational analysis. Features characterizing a well-designed observational study include clearly defined research questions, careful selection of an appropriate data source, consultation with investigators with relevant methodological expertise, inclusion of sensitivity analyses, caution not to overinterpret small but significant differences, and recognition of limitations when trying to evaluate causality. This review concludes that carefully designed and executed studies using observational data that possess these qualities hold substantial promise for advancing our understanding of many unanswered questions of importance to the field of radiation oncology.« less

Considerations for observational research using large data sets in radiation oncology.

PubMed

Jagsi, Reshma; Bekelman, Justin E; Chen, Aileen; Chen, Ronald C; Hoffman, Karen; Shih, Ya-Chen Tina; Smith, Benjamin D; Yu, James B

2014-09-01

The radiation oncology community has witnessed growing interest in observational research conducted using large-scale data sources such as registries and claims-based data sets. With the growing emphasis on observational analyses in health care, the radiation oncology community must possess a sophisticated understanding of the methodological considerations of such studies in order to evaluate evidence appropriately to guide practice and policy. Because observational research has unique features that distinguish it from clinical trials and other forms of traditional radiation oncology research, the International Journal of Radiation Oncology, Biology, Physics assembled a panel of experts in health services research to provide a concise and well-referenced review, intended to be informative for the lay reader, as well as for scholars who wish to embark on such research without prior experience. This review begins by discussing the types of research questions relevant to radiation oncology that large-scale databases may help illuminate. It then describes major potential data sources for such endeavors, including information regarding access and insights regarding the strengths and limitations of each. Finally, it provides guidance regarding the analytical challenges that observational studies must confront, along with discussion of the techniques that have been developed to help minimize the impact of certain common analytical issues in observational analysis. Features characterizing a well-designed observational study include clearly defined research questions, careful selection of an appropriate data source, consultation with investigators with relevant methodological expertise, inclusion of sensitivity analyses, caution not to overinterpret small but significant differences, and recognition of limitations when trying to evaluate causality. This review concludes that carefully designed and executed studies using observational data that possess these qualities hold substantial promise for advancing our understanding of many unanswered questions of importance to the field of radiation oncology. Copyright © 2014 Elsevier Inc. All rights reserved.

Considerations for Observational Research using Large Datasets in Radiation Oncology

PubMed Central

Jagsi, Reshma; Bekelman, Justin E.; Chen, Aileen; Chen, Ronald C.; Hoffman, Karen; Shih, Ya-Chen Tina; Smith, Benjamin D.; Yu, James B.

2014-01-01

The radiation oncology community has witnessed growing interest in observational research conducted using large-scale data sources such as registries and claims-based datasets. With the growing emphasis on observational analyses in health care, the radiation oncology community must possess a sophisticated understanding of the methodological considerations of such studies in order to evaluate evidence appropriately to guide practice and policy. Because observational research has unique features that distinguish it from clinical trials and other forms of traditional radiation oncology research, the Red Journal assembled a panel of experts in health services research to provide a concise and well-referenced review, intended to be informative for the lay reader, as well as for scholars who wish to embark on such research without prior experience. This review begins by discussing the types of research questions relevant to radiation oncology that large-scale databases may help illuminate. It then describes major potential data sources for such endeavors, including information regarding access and insights regarding the strengths and limitations of each. Finally, it provides guidance regarding the analytic challenges that observational studies must confront, along with discussion of the techniques that have been developed to help minimize the impact of certain common analytical issues in observational analysis. Features characterizing a well-designed observational study include clearly defined research questions, careful selection of an appropriate data source, consultation with investigators with relevant methodological expertise, inclusion of sensitivity analyses, caution not to overinterpret small but significant differences, and recognition of limitations when trying to evaluate causality. This review concludes that carefully designed and executed studies using observational data that possess these qualities hold substantial promise for advancing our understanding of many unanswered questions of importance to the field of radiation oncology. PMID:25195986

Are parent-reported outcomes for self-directed or telephone-assisted behavioral family intervention enhanced if parents are observed?

PubMed

Morawska, Alina; Sanders, Matthew R

2007-05-01

The study examined the effects of conducting observations as part of a broader assessment of families participating in behavior family intervention (BFI). It was designed to investigate whether the observations improve intervention outcomes. Families were randomly assigned to different levels of BFI or a waitlist control condition and subsequently randomly assigned to either observation or no-observation conditions. This study demonstrated significant intervention and observation effects. Mothers in more intensive BFI reported more improvement in their child's behavior and their own parenting. Observed mothers reported lower intensity of child behavior problems and more effective parenting styles. There was also a trend for less anger among mothers who were observed and evidence of an observation-intervention interaction for parental anger, with observed mothers in more intensive intervention reporting less anger compared to those not observed. Implications for clinical and research intervention contexts are discussed.

Supporting Knowledge Integration in Chemistry with a Visualization-Enhanced Inquiry Unit

NASA Astrophysics Data System (ADS)

Chiu, Jennifer L.; Linn, Marcia C.

2014-02-01

This paper describes the design and impact of an inquiry-oriented online curriculum that takes advantage of dynamic molecular visualizations to improve students' understanding of chemical reactions. The visualization-enhanced unit uses research-based guidelines following the knowledge integration framework to help students develop coherent understanding by connecting and refining existing and new ideas. The inquiry unit supports students to develop connections among molecular, observable, and symbolic representations of chemical reactions. Design-based research included a pilot study, a study comparing the visualization-enhanced inquiry unit to typical instruction, and a course-long comparison study featuring a delayed posttest. Students participating in the visualization-enhanced unit outperformed students receiving typical instruction and further consolidated their understanding on the delayed posttest. Students who used the visualization-enhanced unit formed more connections among concepts than students with typical textbook and lecture-based instruction. Item analysis revealed the types of connections students made when studying the curriculum and suggested how these connections enabled students to consolidate their understanding as they continued in the chemistry course. Results demonstrate that visualization-enhanced inquiry designed for knowledge integration can improve connections between observable and atomic-level phenomena and serve students well as they study subsequent topics in chemistry.

Quasi-minimal active disturbance rejection control of MIMO perturbed linear systems based on differential neural networks and the attractive ellipsoid method.

PubMed

Salgado, Iván; Mera-Hernández, Manuel; Chairez, Isaac

2017-11-01

This study addresses the problem of designing an output-based controller to stabilize multi-input multi-output (MIMO) systems in the presence of parametric disturbances as well as uncertainties in the state model and output noise measurements. The controller design includes a linear state transformation which separates uncertainties matched to the control input and the unmatched ones. A differential neural network (DNN) observer produces a nonlinear approximation of the matched perturbation and the unknown states simultaneously in the transformed coordinates. This study proposes the use of the Attractive Ellipsoid Method (AEM) to optimize the gains of the controller and the gain observer in the DNN structure. As a consequence, the obtained control input minimizes the convergence zone for the estimation error. Moreover, the control design uses the estimated disturbance provided by the DNN to obtain a better performance in the stabilization task in comparison with a quasi-minimal output feedback controller based on a Luenberger observer and a sliding mode controller. Numerical results pointed out the advantages obtained by the nonlinear control based on the DNN observer. The first example deals with the stabilization of an academic linear MIMO perturbed system and the second example stabilizes the trajectories of a DC-motor into a predefined operation point. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

Use of Interview and Observation to Clarify Reported Practices of Head Start Staff Concerning Problem Behavior: Implications for Programs and Training

ERIC Educational Resources Information Center

Snell, Martha E.; Voorhees, Mary D.; Berlin, Rebecca A.; Stanton-Chapman, Tina L.; Hadden, Sarah; McCarty, Jane

2012-01-01

This study used interviews and classroom observation to follow up a survey of 78 Head Start staff from five programs in the mid-Atlantic region. The purpose of the study was to collect additional details about administrator and staff needs in regard to addressing children's challenging behavior in order to design a PBS in-service intervention.…

NASA Cold Land Processes Experiment (CLPX 2002/03): Local scale observation site

Treesearch

Janet Hardy; Robert Davis; Yeohoon Koh; Don Cline; Kelly Elder; Richard Armstrong; Hans-Peter Marshall; Thomas Painter; Gilles Castres Saint-Martin; Roger DeRoo; Kamal Sarabandi; Tobias Graf; Toshio Koike; Kyle McDonald

2008-01-01

The local scale observation site (LSOS) is the smallest study site (0.8 ha) of the 2002/03 Cold Land Processes Experiment (CLPX) and is located within the Fraser mesocell study area. It was the most intensively measured site of the CLPX, and measurements here had the greatest temporal component of all CLPX sites. Measurements made at the LSOS were designed to produce a...

Determination of Nutrient Intakes by a Modified Visual Estimation Method and Computerized Nutritional Analysis for Dietary Assessments

DTIC Science & Technology

1987-09-01

a useful average for population studies, do not delay data processing , and is relatively Inexpensive. Using MVEN and observing recipe preparation...for population studies, do not delay data processing , and is relatively inexpensive. Using HVEM and observing recipe preparation procedures improve the...extensive review of the procedures and problems in design, collection, analysis, processing and interpretation of dietary survey data for individuals

The Power and Pitfalls of Big Data Research in Obstetrics and Gynecology: A Consumer's Guide.

PubMed

Goodin, Amie; Delcher, Chris; Valenzuela, Chelsea; Wang, Xi; Zhu, Yanmin; Roussos-Ross, Dikea; Brown, Joshua D

2017-11-01

Research in obstetrics and gynecology (OB/GYN) increasingly relies on "big data" and observational study designs. There is a gap in practitioner-relevant guides to interpret and critique such research. This guide is an introduction to interpreting research using observational data and provides explanations and context for related terminology. In addition, it serves as a guide for critiquing OB/GYN studies that use observational data by outlining how to assess common pitfalls of experimental and observational study designs. Lastly, the piece provides a compendium of observational data resources commonly used within OB/GYN research. Review of literature was conducted for the collection of definitions and examples of terminology related to observational data research. Data resources were collected via Web search and researcher recommendations. Next, each data resource was reviewed and analyzed for content and accessibility. Contents of data resources were organized into summary tables and matched to relevant literature examples. We identified 26 observational data resources frequently used in secondary analysis for OB/GYN research. Cost, accessibility considerations for software/hardware capabilities, and contents of each data resource varied substantially. Observational data sources can provide researchers with a variety of options in tackling their research questions related to OB/GYN practice, patient health outcomes, trends in utilization of medications/procedures, or prevalence estimates of disease states. Insurance claims data resources are useful for population-level prevalence estimates and utilization trends, whereas electronic health record-derived data and patient survey data may be more useful for exploring patient behaviors and trends in practice.

High pressure low temperature studies on 1-2-2 iron-based superconductors using designer diamond cells

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

Uhoya, Walter O.; Tsoi, Georgiy M.; Vohra, Yogesh K.

In this study, high pressure low temperature electrical resistance measurements were carried out on a series of 122 iron-based superconductors using a designer diamond anvil cell. These studies were complemented by image plate x-ray diffraction measurements under high pressures and low temperatures at beamline 16-BM-D, HPCAT, Advanced Photon Source. A common feature of the 1-2-2 iron-based materials is the observation of anomalous compressibility effects under pressure and a Tetragonal (T) to Collapsed Tetragonal (CT) phase transition under high pressures. Specific studies on antiferromagnetic spin-density-wave Ba 0.5Sr 0.5Fe 2As 2 and Ba(Fe 0.9Ru 0.1) 2As 2 samples are presented to 10more » K and 41 GPa. The collapsed tetragonal phase was observed at a pressure of 14 GPa in Ba 0.5Sr 0.5Fe 2As 2 at ambient temperature. The highest superconducting transition temperature in Ba 0.5Sr 0.5Fe 2As 2 was observed to be at 32 K at a pressure of 4.7 GPa. The superconductivity was observed to be suppressed on transformation to the CT phase in 122 materials.« less

Combining Computational and Social Effort for Collaborative Problem Solving

PubMed Central

Wagy, Mark D.; Bongard, Josh C.

2015-01-01

Rather than replacing human labor, there is growing evidence that networked computers create opportunities for collaborations of people and algorithms to solve problems beyond either of them. In this study, we demonstrate the conditions under which such synergy can arise. We show that, for a design task, three elements are sufficient: humans apply intuitions to the problem, algorithms automatically determine and report back on the quality of designs, and humans observe and innovate on others’ designs to focus creative and computational effort on good designs. This study suggests how such collaborations should be composed for other domains, as well as how social and computational dynamics mutually influence one another during collaborative problem solving. PMID:26544199

Development of Souvenir Production Transaction Processing System

NASA Astrophysics Data System (ADS)

Rumambi, H.; Kaparang, R.; Lintong, J.

2018-01-01

This research aims to design a souvenir production transaction processing system for the craftsmen in North Sulawesi. The craftsmen make very simple recordings about souvenir production transactions and use documents that are not in accordance with the generally accepted accounting practices. This research uses qualitative method. The data is collected through interviews, observations, documents and literatures studies. The research stages are conducted in preliminary studies, data collection, data analyzed and system design. The design of system is built from chart of account, accounting cycle and documents as input and get processed in accounting recording. The outputs are financial statements. The system design provides benefits for the craftsmen in assessing the financial performance and getting financing from bank.

Far-infrared spectrophotometer for astronomical observations

NASA Technical Reports Server (NTRS)

Moseley, H.; Silverberg, R. F.

1981-01-01

A liquid-helium-cooled far infrared spectrophotometer was built and used to make low resolution observations of the continua of several kinds of astronomical objects using the Kuiper Airborne Observatory. This instrument fills a gap in both sensitivity to continuum sources and spectral resolution between the broadband photometers with lambda/Delta lambda approximately 1 and spectrometers with lambda/Delta lambda greater than 50. While designed primarily to study planetary nebulae, the instrument permits study of the shape of the continua of many weak sources which cannot easily be observed with high resolution systems.

Objective categorization of interferential tear film lipid layer pattern: validation of the technique

NASA Astrophysics Data System (ADS)

García-Resúa, C.; Giráldez, M. J.; Barreira, N.; Penedo, M. G.; Yebra-Pimentel, E.

2011-05-01

Purpose: The lipid layer of the tear film limits evaporation during the inter-blink interval and also affects tear stability. This study was designed to validate a new software application designed to characterize the tear film lipid layer through texture and colour pattern recognition. Methods: Using the Tearscope-plus (slit lamp magnification 200X), the lipid layer was examined in 105 healthy young adults and interference photographs acquired with a Topcon DV-3 digital camera. The photographs were classified by the new software and by 2 further observers (observer 1 and observer 2) with experience in examining the eye surface. Results: Strong correlation was detected between the categories determined by the new application, observer 1 and observer 2 (Cramer's V, from 0.81 to 0.87, p<0.001). Best agreement (96.2%) was noted between the new method and observers 1 and 2 for recognizing meshwork patterns, whereas observers 1 and 2 showed greatest correspondence when classifying colour fringe patterns. Conclusions: The new application can objectively categorize LLPs using the Tearscope-plus.

From the Cover: Understanding nature's design for a nanosyringe

NASA Astrophysics Data System (ADS)

Lopez, Carlos F.; Nielsen, Steve O.; Moore, Preston B.; Klein, Michael L.

2004-03-01

Synthetic and natural peptide assemblies can possess transport or conductance activity across biomembranes through the formation of nanopores. The fundamental mechanisms of membrane insertion necessary for antimicrobial or synthetic pore formation are poorly understood. We observe a lipid-assisted mechanism for passive insertion into a model membrane from molecular dynamics simulations. The assembly used in the study, a generic nanotube functionalized with hydrophilic termini, is assisted in crossing the membrane core by transleaflet lipid flips. Lipid tails occlude a purely hydrophobic nanotube. The observed insertion mechanism requirements for hydrophobic-hydrophilic matching have implications for the design of synthetic channels and antibiotics.

From observational to dynamic genetics

PubMed Central

Haworth, Claire M. A.; Davis, Oliver S. P.

2014-01-01

Twin and family studies have shown that most traits are at least moderately heritable. But what are the implications of finding genetic influence for the design of intervention and prevention programs? For complex traits, heritability does not mean immutability, and research has shown that genetic influences can change with age, context, and in response to behavioral and drug interventions. The most significant implications for intervention will come when we move from observational genetics to investigating dynamic genetics, including genetically sensitive interventions. Future interventions should be designed to overcome genetic risk and draw upon genetic strengths by changing the environment. PMID:24478793

Software and electronic developments for TUG - T60 robotic telescope

NASA Astrophysics Data System (ADS)

Parmaksizoglu, M.; Dindar, M.; Kirbiyik, H.; Helhel, S.

2014-12-01

A robotic telescope is a telescope that can make observations without hands-on human control. Its low level behavior is automatic and computer-controlled. Robotic telescopes usually run under the control of a scheduler, which provides high-level control by selecting astronomical targets for observation. TUBITAK National Observatory (TUG) T60 Robotic Telescope is controlled by open source OCAAS software, formally named TALON. This study introduces the improvements on TALON software, new electronic and mechanic designs. The designs and software improvements were implemented in the T60 telescope control software and tested on the real system successfully.

A Compact Airborne High Spectral Resolution Lidar for Observations of Aerosol and Cloud Optical Properties

NASA Technical Reports Server (NTRS)

Hostetler, Chris A.; Hair, John W.; Cook, Anthony L.

2002-01-01

We are in the process of developing a nadir-viewing, aircraft-based high spectral resolution lidar (HSRL) at NASA Langley Research Center. The system is designed to measure backscatter and extinction of aerosols and tenuous clouds. The primary uses of the instrument will be to validate spaceborne aerosol and cloud observations, carry out regional process studies, and assess the predictions of chemical transport models. In this paper, we provide an overview of the instrument design and present the results of simulations showing the instrument's capability to accurately measure extinction and extinction-to-backscatter ratio.

Design of Experiments for Both Experimental and Analytical Study of Exhaust Plume Effects on Sonic Boom

NASA Technical Reports Server (NTRS)

Castner, Raymond S.

2009-01-01

Computational fluid dynamics (CFD) analysis has been performed to study the plume effects on sonic boom signature for isolated nozzle configurations. The objectives of these analyses were to provide comparison to past work using modern CFD analysis tools, to investigate the differences of high aspect ratio nozzles to circular (axisymmetric) nozzles, and to report the effects of under expanded nozzle operation on boom signature. CFD analysis was used to address the plume effects on sonic boom signature from a baseline exhaust nozzle. Nearfield pressure signatures were collected for nozzle pressure ratios (NPRs) between 6 and 10. A computer code was used to extrapolate these signatures to a ground-observed sonic boom N-wave. Trends show that there is a reduction in sonic boom N-wave signature as NPR is increased from 6 to 10. As low boom designs are developed and improved, there will be a need for understanding the interaction between the aircraft boat tail shocks and the exhaust nozzle plume. These CFD analyses will provide a baseline study for future analysis efforts. For further study, a design of experiments has been conducted to develop a hybrid method where both CFD and small scale wind tunnel testing will validate the observed trends. The CFD and testing will be used to screen a number of factors which are important to low boom propulsion integration, including boat tail angle, nozzle geometry, and the effect of spacing and stagger on nozzle pairs. To design the wind tunnel experiment, CFD was instrumental in developing a model which would provide adequate space to observe the nozzle and boat tail shock structure without interference from the wind tunnel walls.

Logic Design Pathology and Space Flight Electronics

NASA Technical Reports Server (NTRS)

Katz, Richard; Barto, Rod L.; Erickson, K.

1997-01-01

Logic design errors have been observed in space flight missions and the final stages of ground test. The technologies used by designers and their design/analysis methodologies will be analyzed. This will give insight to the root causes of the failures. These technologies include discrete integrated circuit based systems, systems based on field and mask programmable logic, and the use computer aided engineering (CAE) systems. State-of-the-art (SOTA) design tools and methodologies will be analyzed with respect to high-reliability spacecraft design and potential pitfalls are discussed. Case studies of faults from large expensive programs to "smaller, faster, cheaper" missions will be used to explore the fundamental reasons for logic design problems.

75 FR 27649 - 2010 Annual Determination for Sea Turtle Observer Requirements

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-18

... enable the design of an appropriate sampling program and to ensure collection of sufficient scientific... Observer Coverage in a Fishery Listed on the 2010 Annual Determination The design of any observer program.... During the program design, NMFS will be guided by the following standards for distributing and placing...

Optimal Observations for Variational Data Assimilation

NASA Technical Reports Server (NTRS)

Koehl, Armin; Stammer, Detlef

2003-01-01

An important aspect of Ocean state estimation is the design of an observing system that allows the efficient study of climate aspects in the ocean. A solution of the design problem is presented here in terms of optimal observations that emerge as nondimensionalized singular vectors of the modified data resolution matrix. The actual computation is feasible only for scalar quantities in the limit of large observational errors. In the framework of a lo resolution North Atlantic primitive equation model it is demonstrated that such optimal observations when applied to determining the strength of the volume and heat transport across the Greenland-Scotland ridge, perform significantly better than traditional section data. On seasonal to inter-annual time-scales optimal observations are located primarily along the continental shelf and information about heat-transport, wind stress and stratification is being communicated via boundary waves and advective processes. On time-scales of about a month, sea surface height observations appear to be more efficient in reconstructing the cross-ridge heat transport than hydrographic observations. Optimal observations also provide a tool for understanding how the ocean state is effected by anomalies of integral quantities such as meridional heat transport.

Finding a Middle Ground: Exploring the Impact of Patient- and Family-Centered Design on Nurse-Family Interactions in the Neuro ICU.

PubMed

Rippin, Allyn S; Zimring, Craig; Samuels, Owen; Denham, Megan E

2015-01-01

This comparative study of two adult neuro critical care units examined the impact of patient- and family-centered design on nurse-family interactions in a unit designed to increase family involvement. A growing evidence base suggests that the built environment can facilitate the delivery of patient- and family-centered care (PFCC). However, few studies examine how the PFCC model impacts the delivery of care, specifically the role of design in nurse-family interactions in the adult intensive care unit (ICU) from the perspective of the bedside nurse. Two neuro ICUs with the same patient population and staff, but with different layouts, were compared. Structured observations were conducted to assess changes in the frequency, location, and content of interactions between the two units. Discussions with staff provided additional insights into nurse attitudes, perceptions, and experiences caring for families. Nurses reported challenges balancing the needs of many stakeholders in a complex clinical environment, regardless of unit layout. However, differences in communication patterns between the clinician- and family-centered units were observed. More interactions were observed in nurse workstations in the PFCC unit, with most initiated by family. While the new unit was seen as more conducive to the delivery of PFCC, some nurses reported a loss of workspace control. Patient- and family-centered design created new spatial and temporal opportunities for nurse-family interactions in the adult ICU, thus supporting PFCC goals. However, greater exposure to unplanned family encounters may increase nurse stress without adequate spatial and organizational support. © The Author(s) 2015.

Embedding clinical interventions into observational studies

PubMed Central

Newman, Anne B.; Avilés-Santa, M. Larissa; Anderson, Garnet; Heiss, Gerardo; Howard, Wm. James; Krucoff, Mitchell; Kuller, Lewis H.; Lewis, Cora E.; Robinson, Jennifer G.; Taylor, Herman; Treviño, Roberto P.; Weintraub, William

2017-01-01

Novel approaches to observational studies and clinical trials could improve the cost-effectiveness and speed of translation of research. Hybrid designs that combine elements of clinical trials with observational registries or cohort studies should be considered as part of a long-term strategy to transform clinical trials and epidemiology, adapting to the opportunities of big data and the challenges of constrained budgets. Important considerations include study aims, timing, breadth and depth of the existing infrastructure that can be leveraged, participant burden, likely participation rate and available sample size in the cohort, required sample size for the trial, and investigator expertise. Community engagement and stakeholder (including study participants) support are essential for these efforts to succeed. PMID:26611435

New angles on energy correlation functions

DOE PAGES

Moult, Ian; Necib, Lina; Thaler, Jesse

2016-12-29

Jet substructure observables, designed to identify specific features within jets, play an essential role at the Large Hadron Collider (LHC), both for searching for signals beyond the Standard Model and for testing QCD in extreme phase space regions. In this paper, we systematically study the structure of infrared and collinear safe substructure observables, defining a generalization of the energy correlation functions to probe n-particle correlations within a jet. These generalized correlators provide a flexible basis for constructing new substructure observables optimized for specific purposes. Focusing on three major targets of the jet substructure community — boosted top tagging, boosted W/Z/Hmore » tagging, and quark/gluon discrimination — we use power-counting techniques to identify three new series of powerful discriminants: M i, N i, and U i. The Mi series is designed for use on groomed jets, providing a novel example of observables with improved discrimination power after the removal of soft radiation. The N i series behave parametrically like the N -subjettiness ratio observables, but are defined without respect to subjet axes, exhibiting improved behavior in the unresolved limit. Finally, the U i series improves quark/gluon discrimination by using higher-point correlators to simultaneously probe multiple emissions within a jet. Taken together, these observables broaden the scope for jet substructure studies at the LHC.« less

New angles on energy correlation functions

NASA Astrophysics Data System (ADS)

Moult, Ian; Necib, Lina; Thaler, Jesse

2016-12-01

Jet substructure observables, designed to identify specific features within jets, play an essential role at the Large Hadron Collider (LHC), both for searching for signals beyond the Standard Model and for testing QCD in extreme phase space regions. In this paper, we systematically study the structure of infrared and collinear safe substructure observables, defining a generalization of the energy correlation functions to probe n-particle correlations within a jet. These generalized correlators provide a flexible basis for constructing new substructure observables optimized for specific purposes. Focusing on three major targets of the jet substructure community — boosted top tagging, boosted W/Z/H tagging, and quark/gluon discrimination — we use power-counting techniques to identify three new series of powerful discriminants: M i , N i , and U i . The M i series is designed for use on groomed jets, providing a novel example of observables with improved discrimination power after the removal of soft radiation. The N i series behave parametrically like the N -subjettiness ratio observables, but are defined without respect to subjet axes, exhibiting improved behavior in the unresolved limit. Finally, the U i series improves quark/gluon discrimination by using higher-point correlators to simultaneously probe multiple emissions within a jet. Taken together, these observables broaden the scope for jet substructure studies at the LHC.

Peer Observation of Teaching in University Departments: A Framework for Implementation

ERIC Educational Resources Information Center

Bell, Maureen; Cooper, Paul

2013-01-01

Academics in an engineering school at an Australian university participated in peer observation of a teaching program using a partnership approach. The present case study explains and discusses program aims, design, process and outcomes. The success of the program was dependent on four critical elements: educational leadership; a staged,…

Classroom Observation Data and Instruction in Primary Mathematics Education: Improving Design and Rigour

ERIC Educational Resources Information Center

Thompson, Carla J.; Davis, Sandra B.

2014-01-01

The use of formal observation in primary mathematics classrooms is supported in the literature as a viable method of determining effective teaching strategies and appropriate tasks for inclusion in the early years of mathematics learning. The twofold aim of this study was to (a) investigate predictive relationships between primary mathematics…

Finite element corroboration of buckling phenomena observed in corrugated boxes

Treesearch

Thomas J. Urbanik; Edmond P. Saliklis

2003-01-01

Conventional compression strength formulas for corrugated fiberboard boxes are limited to geometry and material that produce an elastic postbuckling failure. Inelastic postbuckling can occur in squatty boxes and trays, but a mechanistic rationale for unifying observed strength data is lacking. This study combines a finite element model with a parametric design of the...

How to Augment the Learning Impact of Computer Simulations? The Designs and Effects of Interactivity and Scaffolding

ERIC Educational Resources Information Center

Chang, Hsin-Yi

2017-01-01

Two investigations were conducted in this study. In the first experiment, the effects of two types of interactivity with a computer simulation were compared: experimentation versus observation interactivity. Experimentation interactivity allows students to use simulations to conduct virtual experiments, whereas observation interactivity allows…

Estimating a Meaningful Point of Change: A Comparison of Exploratory Techniques Based on Nonparametric Regression

ERIC Educational Resources Information Center

Klotsche, Jens; Gloster, Andrew T.

2012-01-01

Longitudinal studies are increasingly common in psychological research. Characterized by repeated measurements, longitudinal designs aim to observe phenomena that change over time. One important question involves identification of the exact point in time when the observed phenomena begin to meaningfully change above and beyond baseline…

An Observational Assessment of Physical Activity Levels and Social Behaviour during Elementary School Recess

ERIC Educational Resources Information Center

Roberts, Simon J.; Fairclough, Stuart J.; Ridgers, Nicola D.; Porteous, Conor

2013-01-01

Objective: The purpose of the present study was to assess children's physical activity, social play behaviour, activity type and social interactions during elementary school recess using a pre-validated systematic observation system. Design: Cross-sectional. Setting: Two elementary schools located in Merseyside, England. Method: Fifty-six…

Self-Observation Model Employing an Instinctive Interface for Classroom Active Learning

ERIC Educational Resources Information Center

Chen, Gwo-Dong; Nurkhamid; Wang, Chin-Yeh; Yang, Shu-Han; Chao, Po-Yao

2014-01-01

In a classroom, obtaining active, whole-focused, and engaging learning results from a design is often difficult. In this study, we propose a self-observation model that employs an instinctive interface for classroom active learning. Students can communicate with virtual avatars in the vertical screen and can react naturally according to the…

Teaching for Creativity by Science Teachers in Grades 5-10

ERIC Educational Resources Information Center

Al-Abdali, Nasser S.; Al-Balushi, Sulaiman M.

2016-01-01

This classroom observation study explored how science teachers (N = 22) teach for creativity in grades 5-10 in Oman. We designed an observation form with 4 main categories that targeted the instructional practices related to teaching for creativity: questioning strategy, teacher's responses to students' ideas, classroom activities to support…

Observational and Incidental Learning by Children with Autism during Small Group Instruction

ERIC Educational Resources Information Center

Ledford, Jennifer R.; Gast, David L.; Luscre, Deanna; Ayres, Kevin M.

2008-01-01

This study evaluated the acquisition of incidental and observational information presented to 6 children with autism in a small group instructional arrangement using a constant time delay (CTD) procedure. A multiple probe design across behaviors, replicated across 6 participants, was used to evaluate the effectiveness of the CTD procedure and to…

Observation Projects: People-Watching for Fun and Learning.

ERIC Educational Resources Information Center

Litterst, Judith K.

In keeping with the trend toward active, participative learning, observation projects for speech communication students can allow them to experiment with designing and carrying out a study of human communication. Students can be encouraged to look at the dynamics of a church congregation, a courtroom, a pre-game football huddle, or an office, and…

Considerations for the design, analysis and presentation of in vivo studies.

PubMed

Ranstam, J; Cook, J A

2017-03-01

To describe, explain and give practical suggestions regarding important principles and key methodological challenges in the study design, statistical analysis, and reporting of results from in vivo studies. Pre-specifying endpoints and analysis, recognizing the common underlying assumption of statistically independent observations, performing sample size calculations, and addressing multiplicity issues are important parts of an in vivo study. A clear reporting of results and informative graphical presentations of data are other important parts. Copyright © 2016 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

An Optimal Design for Placements of Tsunami Observing Systems Around the Nankai Trough, Japan

NASA Astrophysics Data System (ADS)

Mulia, I. E.; Gusman, A. R.; Satake, K.

2017-12-01

Presently, there are numerous tsunami observing systems deployed in several major tsunamigenic regions throughout the world. However, documentations on how and where to optimally place such measurement devices are limited. This study presents a methodological approach to select the best and fewest observation points for the purpose of tsunami source characterizations, particularly in the form of fault slip distributions. We apply the method to design a new tsunami observation network around the Nankai Trough, Japan. In brief, our method can be divided into two stages: initialization and optimization. The initialization stage aims to identify favorable locations of observation points, as well as to determine the initial number of observations. These points are generated based on extrema of an empirical orthogonal function (EOF) spatial modes derived from 11 hypothetical tsunami events in the region. In order to further improve the accuracy, we apply an optimization algorithm called a mesh adaptive direct search (MADS) to remove redundant measurements from the initially generated points by the first stage. A combinatorial search by the MADS will improve the accuracy and reduce the number of observations simultaneously. The EOF analysis of the hypothetical tsunamis using first 2 leading modes with 4 extrema on each mode results in 30 observation points spread along the trench. This is obtained after replacing some clustered points within the radius of 30 km with only one representative. Furthermore, the MADS optimization can improve the accuracy of the EOF-generated points by approximately 10-20% with fewer observations (23 points). Finally, we compare our result with the existing observation points (68 stations) in the region. The result shows that the optimized design with fewer number of observations can produce better source characterizations with approximately 20-60% improvement of accuracies at all the 11 hypothetical cases. It should be note, however, that our design is a tsunami-based approach, some of the existing observing systems are equipped with additional devices to measure other parameter of interests, i.e., for monitoring seismic activities.

The cognitive demands of standardized patients: understanding limitations in attention and working memory with the decoding of nonverbal behavior during improvisations.

PubMed

Newlin-Canzone, Elizabeth T; Scerbo, Mark W; Gliva-McConvey, Gayle; Wallace, Amelia M

2013-08-01

This study was designed to look at the challenges of standardized patients while in role and to use the findings to enhance training methods. The study investigated the effect of improvisations and multiple-task performance on the ability of standardized patients to observe and evaluate another's communication behaviors and its associated mental workload. Twenty standardized patients participated in a 2 types of interview (with and without improvisations)-by-2 types of observation (passive and active) within-groups design. The results indicated that both active observations and improvisations had a negative effect on the standardized patients' ability to observe the learner, missing more than 75% of nonverbal behaviors during active improvisational encounters. Moreover, standardized patients experienced the highest mental demand during active improvisational encounters. The findings suggest that the need to simultaneously portray a character and assess a learner may negatively affect the ability of standardized patients to provide accurate evaluations of a learner, particularly when they are required to improvise responses, underscoring the need for specific and targeted training.

Interpreting observational studies: why empirical calibration is needed to correct p-values

PubMed Central

Schuemie, Martijn J; Ryan, Patrick B; DuMouchel, William; Suchard, Marc A; Madigan, David

2014-01-01

Often the literature makes assertions of medical product effects on the basis of ‘ p < 0.05’. The underlying premise is that at this threshold, there is only a 5% probability that the observed effect would be seen by chance when in reality there is no effect. In observational studies, much more than in randomized trials, bias and confounding may undermine this premise. To test this premise, we selected three exemplar drug safety studies from literature, representing a case–control, a cohort, and a self-controlled case series design. We attempted to replicate these studies as best we could for the drugs studied in the original articles. Next, we applied the same three designs to sets of negative controls: drugs that are not believed to cause the outcome of interest. We observed how often p < 0.05 when the null hypothesis is true, and we fitted distributions to the effect estimates. Using these distributions, we compute calibrated p-values that reflect the probability of observing the effect estimate under the null hypothesis, taking both random and systematic error into account. An automated analysis of scientific literature was performed to evaluate the potential impact of such a calibration. Our experiment provides evidence that the majority of observational studies would declare statistical significance when no effect is present. Empirical calibration was found to reduce spurious results to the desired 5% level. Applying these adjustments to literature suggests that at least 54% of findings with p < 0.05 are not actually statistically significant and should be reevaluated. © 2013 The Authors. Statistics in Medicine published by John Wiley & Sons Ltd. PMID:23900808

Icon and user interface design for emergency medical information systems: a case study.

PubMed

Salman, Y Batu; Cheng, Hong-In; Patterson, Patrick E

2012-01-01

A usable medical information system should allow for reliable and accurate interaction between users and the system in emergencies. A participatory design approach was used to develop a medical information system in two Turkish hospitals. The process consisted of task and user analysis, an icon design survey, initial icon design, final icon design and evaluation, and installation of the iconic medical information system with the icons. We observed work sites to note working processes and tasks related to the information system and interviewed medical personnel. Emergency personnel then participated in the design process to develop a usable graphical user interface, by drawing icon sketches for 23 selected tasks. Similar sketches were requested for specific tasks such as family medical history, contact information, translation, addiction, required inspections, requests and applications, and nurse observations. The sketches were analyzed and redesigned into computer icons by professional designers and the research team. A second group of physicians and nurses then tested the understandability of the icons. The user interface layout was examined and evaluated by system users, followed by the system's installation. Medical personnel reported the participatory design process was interesting and believed the resulting designs would be more familiar and friendlier. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Periprosthetic bone remodelling of short-stem total hip arthroplasty: a systematic review.

PubMed

Yan, Shuang G; Weber, Patrick; Steinbrück, Arnd; Hua, Xingyi; Jansson, Volkmar; Schmidutz, Florian

2017-11-27

Short-stem hip arthroplasty (SHA) was designed to preserve bone stock and provide an improved load transfer. To gain more evidence regarding the load transfer, this review analysed the periprosthetic bone remodelling of SHA in comparison to standard hip arthroplasty (THA). PubMed and ScienceDirect were screened to extract dual-energy X-ray absorptiometry (DXA) studies evaluating the periprosthetic bone remodelling of SHA and two proven THA designs. From the studies included, the postoperative change in periprosthetic bone mineral density (BMD) after one year and the trend over two years was determined. Fifteen studies with four SHAs (CFP, Metha, Nanos, Fitmore) and two THAs (CLS and Bicontact) designs were included. All SHA and THA stems revealed an initial decrease at the calcar and major trochanter (Gruen 1 and 7) with the Metha, Nanos and Fitmore showing a smaller and more balanced remodelling compared to THA. The pattern after one year and the trend over two years argue for a methaphyseal anchorage of the Metha and Nanos, whereas the Fitmore and CFP seem to anchor metha-diaphyseal. Clearly different pattern of bone remodelling were observed between all four SHAs. Periprosthetic bone remodelling is also present in SHA, with the main bone reduction observed proximally. However, certain SHA stems show a more balanced remodelling compared to THA, arguing for a favourable load transfer. Also, the femoral length where bone remodelling occurs is clearly shorter in SHA. As distinctively different pattern between the SHA designs were observed, they should not be judged as a single implant group.

Thermal and cryogenic design study for space infrared telescope facility (SIRTF)

NASA Technical Reports Server (NTRS)

Urbach, A. R.; Kelly, T.; Poley, R.

1984-01-01

A study was conducted to determine the ability of an all superfluid helium design to meet the performance requirements of background limited to 200 micrometer, and a two year lifetime for a one meter class free flying infrared observatory. Both a 98 deg and 28.5 deg inclination orbits were examined, and aperture shade designs were developed for both orbits. A unique forebaffle cooling design significantly reduces the sensitivity to aperture heat loads. With certain restrictions on observing modes, the study determined that an all superfluid helium Dewar will meet the temperature and lifetime requirements. A dual cryogen SFHe/SH2 system was also investigated for the 28.5 deg orbit and found to provide a more constant forebaffle temperature but with only a slight improvement in lifetime.

Quantifying patterns of dynamics in eye movement to measure goodness in organization of design elements in interior architecture

NASA Astrophysics Data System (ADS)

Mirkia, Hasti; Sangari, Arash; Nelson, Mark; Assadi, Amir H.

2013-03-01

Architecture brings together diverse elements to enhance the observer's measure of esthetics and the convenience of functionality. Architects often conceptualize synthesis of design elements to invoke the observer's sense of harmony and positive affect. How does an observer's brain respond to harmony of design in interior spaces? One implicit consideration by architects is the role of guided visual attention by observers while navigating indoors. Prior visual experience of natural scenes provides the perceptual basis for Gestalt of design elements. In contrast, Gestalt of organization in design varies according to the architect's decision. We outline a quantitative theory to measure the success in utilizing the observer's psychological factors to achieve the desired positive affect. We outline a unified framework for perception of geometry and motion in interior spaces, which integrates affective and cognitive aspects of human vision in the context of anthropocentric interior design. The affective criteria are derived from contemporary theories of interior design. Our contribution is to demonstrate that the neural computations in an observer's eye movement could be used to elucidate harmony in perception of form, space and motion, thus a measure of goodness of interior design. Through mathematical modeling, we argue the plausibility of the relevant hypotheses.

Communities. Community Study Unit, Grade 1. Teacher Edition, Field Trip Guide for Teachers, and Student Book.

ERIC Educational Resources Information Center

Lee County School District, Ft. Myers, FL. Dept. of Environmental Education and Instructional Development Services.

This unit is designed to help first grade students understand the broad concept of community. The students experience a variety of in-class and field trip activities that will expose them to communities. The students observe and compare both natural and human-designed communities. Learning activities include pantomimes, listening activities,…

Similarities and Differences in the Academic Education of Software Engineering and Architectural Design Professionals

ERIC Educational Resources Information Center

Hazzan, Orit; Karni, Eyal

2006-01-01

This article focuses on the similarities and differences in the academic education of software engineers and architects. The rationale for this work stems from our observation, each from the perspective of her or his own discipline, that these two professional design and development processes share some similarities. A pilot study was performed,…

An inexpensive rhizotron design for two-dimensional, horizontal root growth measurements

Treesearch

Adam H. Wiese; Don E. Riemenschneider; Ronald S., Jr. Zalesny

2005-01-01

We designed, constructed, and tested an observational system that supports two-dimensional, horizontal root growth measurements over time without disturbing aboveground plant growth and without the need for destructive sampling of roots. Our rhizotrons allow for (1) studying relatively greater numbers of plants at any given time than is now possible under traditional...

Student Multimedia Autobiographies: The Roles of Technology, Personal Narrative, and Signifying Practices

ERIC Educational Resources Information Center

Keane, Julie Thompson

2010-01-01

In 2009, the Parsons StoryCorps qualitative case study was designed to closely observe the complexity of youth engagement with digital media for self-presentation in an afterschool digital storytelling project designed to provide students with rich, varied uses of technology in a urban middle school in North Carolina. Several frameworks were…

Human Factors in the Design of a Computer-Assisted Instruction System. Technical Progress Report.

ERIC Educational Resources Information Center

Mudge, J. C.

A research project built an author-controlled computer-assisted instruction (CAI) system to study ease-of-use factors in student-system, author-system, and programer-system interfaces. Interfaces were designed and observed in use and systematically revised. Development of course material by authors, use by students, and administrative tasks were…

An Observational Study of Peer Learning for High School Students at a Cybersecurity Camp

ERIC Educational Resources Information Center

Pittman, Jason M.; Pike, Ronald E.

2016-01-01

This paper reports on the design and implementation of a cybersecurity camp offered as a cybersecurity learning experience to a group of female and male high school students. Students ranged in grade level from freshmen to senior. Student demographics, including any existing pre-requisite knowledge, were unknown to camp designers prior to the…

Designing and Piloting a Leadership Daily Practice Log: Using Logs to Study the Practice of Leadership

ERIC Educational Resources Information Center

Spillane, James P.; Zuberi, Anita

2009-01-01

Purpose: This article aims to validate the Leadership Daily Practice (LDP) log, an instrument for conducting research on leadership in schools. Research Design: Using a combination of data sources--namely, a daily practice log, observations, and open-ended cognitive interviews--the authors evaluate the validity of the LDP log. Participants: Formal…

"Space and Consequences": The Influence of the Roundtable Classroom Design on Student Dialogue

ERIC Educational Resources Information Center

Parsons, Caroline S.

2016-01-01

This study sought to explore how the design of both physical and virtual learning spaces influence student dialogue in a modern university. Qualitative analysis of the learning spaces in an undergraduate liberal arts program was conducted. Interview and focus group data from students and faculty, in addition to classroom observations, resulted in…

Learning in and beyond School Gardens with Cyber-Physical Systems

ERIC Educational Resources Information Center

Zuiker, Steven J.; Wright, Kyle

2015-01-01

This design-based research study considers the learner-generated design and refinement of a school garden. We report one enactment of the Connected Gardening project in order to illuminate and understand how a fourth-grade class organizes and refines its garden plot using observations of the physical environment and evaluations of data from a…

Gender Differences in Figural Matrices: The Moderating Role of Item Design Features

ERIC Educational Resources Information Center

Arendasy, Martin E.; Sommer, Markus

2012-01-01

There is a heated debate on whether observed gender differences in some figural matrices in adults can be attributed to gender differences in inductive reasoning/G[subscript f] or differential item functioning and/or test bias. Based on previous studies we hypothesized that three specific item design features moderate the effect size of the gender…

Randomized controlled trials and real-world observational studies in evaluating cardiovascular safety of inhaled bronchodilator therapy in COPD.

PubMed

Kardos, Peter; Worsley, Sally; Singh, Dave; Román-Rodríguez, Miguel; Newby, David E; Müllerová, Hana

2016-01-01

Long-acting muscarinic antagonist (LAMA) or long-acting β2-agonist (LABA) bronchodilators and their combination are recommended for the maintenance treatment of chronic obstructive pulmonary disease (COPD). Although the efficacy of LAMAs and LABAs has been well established through randomized controlled trials (RCTs), questions remain regarding their cardiovascular (CV) safety. Furthermore, while the safety of LAMA and LABA monotherapy has been extensively studied, data are lacking for LAMA/LABA combination therapy, and the majority of the studies that have reported on the CV safety of LAMA/LABA combination therapy were not specifically designed to assess this. Evaluation of CV safety for COPD treatments is important because many patients with COPD have underlying CV comorbidities. However, severe CV and other comorbidities are often exclusion criteria for RCTs, contributing to a lack in external validity and generalizability. Real-world observational studies are another important tool to evaluate the effectiveness and safety of COPD therapies in a broader population of patients and can improve upon the external validity limitations of RCTs. We examine what is already known regarding the CV and cerebrovascular safety of LAMA/LABA combination therapy from RCTs and real-world observational studies, and explore the advantages and limitations of data derived from each study type. We also describe an ongoing prospective, observational, comparative post-authorization safety study of a LAMA/LABA combination therapy (umeclidinium/vilanterol) and LAMA monotherapy (umeclidinium) versus tiotropium, with a focus on the relative merits of the study design.

Platelet-rich plasma in orthopedic therapy: a comparative systematic review of clinical and experimental data in equine and human musculoskeletal lesions.

PubMed

Brossi, Patrícia M; Moreira, Juliana J; Machado, Thaís S L; Baccarin, Raquel Y A

2015-04-22

This systematic review aimed to present and critically appraise the available information on the efficacy of platelet rich plasma (PRP) in equine and human orthopedic therapeutics and to verify the influence of study design and methodology on the assumption of PRP's efficacy. We searched Medline, PubMed, Embase, Bireme and Google Scholar without restrictions until July 2013. Randomized trials, human cohort clinical studies or case series with a control group on the use of PRP in tendons, ligaments or articular lesions were included. Equine clinical studies on the same topics were included independently of their design. Experimental studies relevant to the clarification of PRP's effects and mechanisms of action in tissues of interest, conducted in any animal species, were selected. This review included 123 studies. PRP's beneficial effects were observed in 46.7% of the clinical studies, while the absence of positive effects was observed in 43.3%. Among experimental studies, 73% yielded positive results, and 7.9% yielded negative results. The most frequent flaws in the clinical trials' designs were the lack of a true placebo group, poor product characterization, insufficient blinding, small sampling, short follow-up periods, and adoption of poor outcome measures. The methods employed for PRP preparation and administration and the selected outcome measures varied greatly. Poor study design was a common feature of equine clinical trials. From studies in which PRP had beneficial effects, 67.8% had an overall high risk of bias. From the studies in which PRP failed to exhibit beneficial effects, 67.8% had an overall low risk of bias. Most experimental studies revealed positive effects of PRP. Although the majority of equine clinical studies yielded positive results, the human clinical trials' results failed to corroborate these findings. In both species, beneficial results were more frequently observed in studies with a high risk of bias. The use of PRP in musculoskeletal lesions, although safe and promising, has still not shown strong evidence in clinical scenarios.

Advancing Methods for U.S. Transgender Health Research

PubMed Central

Reisner, Sari L.; Deutsch, Madeline B.; Bhasin, Shalender; Bockting, Walter; Brown, George R.; Feldman, Jamie; Garofalo, Rob; Kreukels, Baudewijntje; Radix, Asa; Safer, Joshua D.; Tangpricha, Vin; T’Sjoen, Guy; Goodman, Michael

2016-01-01

Purpose of Review To describe methodological challenges, gaps, and opportunities in U.S. transgender health research. Recent Findings Lack of large prospective observational studies and intervention trials, limited data on risks and benefits of gender affirmation (e.g., hormones and surgical interventions), and inconsistent use of definitions across studies hinder evidence-based care for transgender people. Systematic high-quality observational and intervention-testing studies may be carried out using several approaches, including general population-based, health systems-based, clinic-based, venue-based, and hybrid designs. Each of these approaches has its strength and limitations; however, harmonization of research efforts is needed. Ongoing development of evidence-based clinical recommendations will benefit from a series of observational and intervention studies aimed at identification, recruitment, and follow-up of transgender people of different ages, from different racial, ethnic, and socioeconomic backgrounds and with diverse gender identities. Summary Transgender health research faces challenges that include standardization of lexicon, agreed-upon population definitions, study design, sampling, measurement, outcome ascertainment, and sample size. Application of existing and new methods is needed to fill existing gaps, increase the scientific rigor and reach of transgender health research, and inform evidence-based prevention and care for this underserved population. PMID:26845331

Development of a truss joint for robotic assembly of space structures

NASA Technical Reports Server (NTRS)

Parma, George F.

1992-01-01

This report presents the results of a detailed study of mechanical fasteners which were designed to facilitate robotic assembly of structures. Design requirements for robotic structural assembly were developed, taking into account structural properties and overall system design, and four candidate fasteners were designed to meet them. These fasteners were built and evaluated in the laboratory, and the Hammer-Head joint was chosen as superior overall. It had a high reliability of fastening under misalignments of 2.54 mm (0.1 in) and 3 deg, the highest end fixity (2.18), the simplest end effector, an integral capture guide, good visual verification, and the lightest weight (782 g, 1.72 lb). The study found that a good design should incorporate chamfers sliding on chamfers, cylinders sliding on chamfers, and hard surface finishes on sliding surfaces. The study also comments on robot flexibility, sag, hysteresis, thermal expansion, and friction which were observed during the testing.

Elementary Students' Acquisition of Academic Vocabulary Through Engineering Design

NASA Astrophysics Data System (ADS)

Kugelmass, Rachel

This study examines how STEM (science, technology, engineering, and mathematics) inquiry-based learning through a hands-on engineering design can be beneficial in helping students acquire academic vocabulary. This research took place in a second grade dual- language classroom in a public, suburban elementary school. English language learners, students who speak Spanish at home, and native English speakers were evaluated in this study. Each day, students were presented with a general academic vocabulary focus word during an engineering design challenge. Vocabulary pre-tests and post-tests as well as observation field notes were used to evaluate the student's growth in reading and defining the focus academic vocabulary words. A quiz and KSB (knowledge and skill builder) packet were used to evaluate students' knowledge of science and math content and engineering design. The results of this study indicate that engineering design is an effective means for teaching academic vocabulary to students with varying levels of English proficiency.

Media Coverage, Journal Press Releases and Editorials Associated with Randomized and Observational Studies in High-Impact Medical Journals: A Cohort Study

PubMed Central

Wang, Michael T. M.; Bolland, Mark J.; Gamble, Greg; Grey, Andrew

2015-01-01

Background Publication of clinical research findings in prominent journals influences health beliefs and medical practice, in part by engendering news coverage. Randomized controlled trials (RCTs) should be most influential in guiding clinical practice. We determined whether study design of clinical research published in high-impact journals influences media coverage. Methods and Findings We compared the incidence and amount of media coverage of RCTs with that of observational studies published in the top 7 medical journals between 1 January 2013 and 31 March 2013. We specifically assessed media coverage of the most rigorous RCTs, those with >1000 participants that reported ‘hard’ outcomes. There was no difference between RCTs and observational studies in coverage by major newspapers or news agencies, or in total number of news stories generated (all P>0.63). Large RCTs reporting ‘hard’ outcomes did not generate more news coverage than small RCTs that reported surrogate outcomes and observational studies (all P>0.32). RCTs were more likely than observational studies to attract a journal editorial (70% vs 46%, P = 0.003), but less likely to be the subject of a journal press release (17% vs 50%, P<0.001). Large RCTs that reported ‘hard’ outcomes did not attract an editorial more frequently than other studies (61% vs 58%, P>0.99), nor were they more likely to be the subject of a journal press release (14% vs 38%, P = 0.14). Conclusions The design of clinical studies whose results are published in high-impact medical journals is not associated with the likelihood or amount of ensuing news coverage. PMID:26701758

Design and implementation of a dual-wavelength intrinsic fluorescence camera system

NASA Astrophysics Data System (ADS)

Ortega-Martinez, Antonio; Musacchia, Joseph J.; Gutierrez-Herrera, Enoch; Wang, Ying; Franco, Walfre

2017-03-01

Intrinsic UV fluorescence imaging is a technique that permits the observation of spatial differences in emitted fluorescence. It relies on the fluorescence produced by the innate fluorophores in the sample, and thus can be used for marker-less in-vivo assessment of tissue. It has been studied as a tool for the study of the skin, specifically for the classification of lesions, the delimitation of lesion borders and the study of wound healing, among others. In its most basic setup, a sample is excited with a narrow-band UV light source and the resulting fluorescence is imaged with a UV sensitive camera filtered to the emission wavelength of interest. By carefully selecting the excitation/emission pair, we can observe changes in fluorescence associated with physiological processes. One of the main drawbacks of this simple setup is the inability to observe more than a single excitation/emission pair at the same time, as some phenomena are better studied when two or more different pairs are studied simultaneously. In this work, we describe the design and the hardware and software implementation of a dual wavelength portable UV fluorescence imaging system. Its main components are an UV camera, a dual wavelength UV LED illuminator (295 and 345 nm) and two different emission filters (345 and 390 nm) that can be swapped by a mechanical filter wheel. The system is operated using a laptop computer and custom software that performs basic pre-processing to improve the image. The system was designed to allow us to image fluorescent peaks of tryptophan and collagen cross links in order to study wound healing progression.

Observational Research: Formalized Curiosity

ERIC Educational Resources Information Center

Skaggs, Paul

2004-01-01

Design research is a valuable tool to help the designer understand the problem that he/she needs to solve. The purpose of design research is to help state or understand the problems better, which will lead to better solutions. Observational research is a design research method for helping the designer understand and define the problem.…

Cluster designs to assess the prevalence of acute malnutrition by lot quality assurance sampling: a validation study by computer simulation

PubMed Central

Olives, Casey; Pagano, Marcello; Deitchler, Megan; Hedt, Bethany L; Egge, Kari; Valadez, Joseph J

2009-01-01

Traditional lot quality assurance sampling (LQAS) methods require simple random sampling to guarantee valid results. However, cluster sampling has been proposed to reduce the number of random starting points. This study uses simulations to examine the classification error of two such designs, a 67×3 (67 clusters of three observations) and a 33×6 (33 clusters of six observations) sampling scheme to assess the prevalence of global acute malnutrition (GAM). Further, we explore the use of a 67×3 sequential sampling scheme for LQAS classification of GAM prevalence. Results indicate that, for independent clusters with moderate intracluster correlation for the GAM outcome, the three sampling designs maintain approximate validity for LQAS analysis. Sequential sampling can substantially reduce the average sample size that is required for data collection. The presence of intercluster correlation can impact dramatically the classification error that is associated with LQAS analysis. PMID:20011037

A phantom design and assessment of lesion detectability in PET imaging

NASA Astrophysics Data System (ADS)

Wollenweber, Scott D.; Kinahan, Paul E.; Alessio, Adam M.

2017-03-01

The early detection of abnormal regions with increased tracer uptake in positron emission tomography (PET) is a key driver of imaging system design and optimization as well as choice of imaging protocols. Detectability, however, remains difficult to assess due to the need for realistic objects mimicking the clinical scene, multiple lesion-present and lesion-absent images and multiple observers. Fillable phantoms, with tradeoffs between complexity and utility, provide a means to quantitatively test and compare imaging systems under truth-known conditions. These phantoms, however, often focus on quantification rather than detectability. This work presents extensions to a novel phantom design and analysis techniques to evaluate detectability in the context of realistic, non-piecewise constant backgrounds. The design consists of a phantom filled with small solid plastic balls and a radionuclide solution to mimic heterogeneous background uptake. A set of 3D-printed regular dodecahedral `features' were included at user-defined locations within the phantom to create `holes' within the matrix of chaotically-packed balls. These features fill at approximately 3:1 contrast to the lumpy background. A series of signal-known-present (SP) and signal-known-absent (SA) sub-images were generated and used as input for observer studies. This design was imaged in a head-like 20 cm diameter, 20 cm long cylinder and in a body-like 36 cm wide by 21 cm tall by 40 cm long tank. A series of model observer detectability indices were compared across scan conditions (count levels, number of scan replicates), PET image reconstruction methods (with/without TOF and PSF) and between PET/CT scanner system designs using the same phantom imaged on multiple systems. The detectability index was further compared to the noise-equivalent count (NEC) level to characterize the relationship between NEC and observer SNR.

Multiobjective sampling design for parameter estimation and model discrimination in groundwater solute transport

USGS Publications Warehouse

Knopman, Debra S.; Voss, Clifford I.

1989-01-01

Sampling design for site characterization studies of solute transport in porous media is formulated as a multiobjective problem. Optimal design of a sampling network is a sequential process in which the next phase of sampling is designed on the basis of all available physical knowledge of the system. Three objectives are considered: model discrimination, parameter estimation, and cost minimization. For the first two objectives, physically based measures of the value of information obtained from a set of observations are specified. In model discrimination, value of information of an observation point is measured in terms of the difference in solute concentration predicted by hypothesized models of transport. Points of greatest difference in predictions can contribute the most information to the discriminatory power of a sampling design. Sensitivity of solute concentration to a change in a parameter contributes information on the relative variance of a parameter estimate. Inclusion of points in a sampling design with high sensitivities to parameters tends to reduce variance in parameter estimates. Cost minimization accounts for both the capital cost of well installation and the operating costs of collection and analysis of field samples. Sensitivities, discrimination information, and well installation and sampling costs are used to form coefficients in the multiobjective problem in which the decision variables are binary (zero/one), each corresponding to the selection of an observation point in time and space. The solution to the multiobjective problem is a noninferior set of designs. To gain insight into effective design strategies, a one-dimensional solute transport problem is hypothesized. Then, an approximation of the noninferior set is found by enumerating 120 designs and evaluating objective functions for each of the designs. Trade-offs between pairs of objectives are demonstrated among the models. The value of an objective function for a given design is shown to correspond to the ability of a design to actually meet an objective.

Beyond access: a case study on the intersection between accessibility, sustainability, and universal design.

PubMed

Gossett, Andrea; Mirza, Mansha; Barnds, Ann Kathleen; Feidt, Daisy

2009-11-01

A growing emphasis has been placed on providing equal opportunities for all people, particularly people with disabilities, to support participation. Barriers to participation are represented in part by physical space restrictions. This article explores the decision-making process during the construction of a new office building housing a disability-rights organization. The building project featured in this study was developed on the principles of universal design, maximal accessibility, and sustainability to support access and participation. A qualitative case study approach was used involving collection of data through in-depth interviews with key decision-makers; non-participant observations at design meetings; and on-site tours. Qualitative thematic analysis along with the development of a classification system was used to understand specific building elements and the relevant decision processes from which they resulted. Recording and analyzing the design process revealed several key issues including grassroots involvement of stakeholders; interaction between universal design and sustainable design; addressing diversity through flexibility and universality; and segregationist accessibility versus universal design. This case study revealed complex interactions between accessibility, universal design, and sustainability. Two visual models were proposed to understand and analyze these complexities.

A probability model for evaluating the bias and precision of influenza vaccine effectiveness estimates from case-control studies.

PubMed

Haber, M; An, Q; Foppa, I M; Shay, D K; Ferdinands, J M; Orenstein, W A

2015-05-01

As influenza vaccination is now widely recommended, randomized clinical trials are no longer ethical in many populations. Therefore, observational studies on patients seeking medical care for acute respiratory illnesses (ARIs) are a popular option for estimating influenza vaccine effectiveness (VE). We developed a probability model for evaluating and comparing bias and precision of estimates of VE against symptomatic influenza from two commonly used case-control study designs: the test-negative design and the traditional case-control design. We show that when vaccination does not affect the probability of developing non-influenza ARI then VE estimates from test-negative design studies are unbiased even if vaccinees and non-vaccinees have different probabilities of seeking medical care against ARI, as long as the ratio of these probabilities is the same for illnesses resulting from influenza and non-influenza infections. Our numerical results suggest that in general, estimates from the test-negative design have smaller bias compared to estimates from the traditional case-control design as long as the probability of non-influenza ARI is similar among vaccinated and unvaccinated individuals. We did not find consistent differences between the standard errors of the estimates from the two study designs.

Facilitating the learning process in design-based learning practices: an investigation of teachers' actions in supervising students

NASA Astrophysics Data System (ADS)

Gómez Puente, S. M.; van Eijck, M.; Jochems, W.

2013-11-01

Background: In research on design-based learning (DBL), inadequate attention is paid to the role the teacher plays in supervising students in gathering and applying knowledge to design artifacts, systems, and innovative solutions in higher education. Purpose: In this study, we examine whether teacher actions we previously identified in the DBL literature as important in facilitating learning processes and student supervision are present in current DBL engineering practices. Sample: The sample (N=16) consisted of teachers and supervisors in two engineering study programs at a university of technology: mechanical and electrical engineering. We selected randomly teachers from freshman and second-year bachelor DBL projects responsible for student supervision and assessment. Design and method: Interviews with teachers, and interviews and observations of supervisors were used to examine how supervision and facilitation actions are applied according to the DBL framework. Results: Major findings indicate that formulating questions is the most common practice seen in facilitating learning in open-ended engineering design environments. Furthermore, other DBL actions we expected to see based upon the literature were seldom observed in the coaching practices within these two programs. Conclusions: Professionalization of teachers in supervising students need to include methods to scaffold learning by supporting students in reflecting and in providing formative feedback.

Effectiveness-implementation hybrid designs: combining elements of clinical effectiveness and implementation research to enhance public health impact.

PubMed

Curran, Geoffrey M; Bauer, Mark; Mittman, Brian; Pyne, Jeffrey M; Stetler, Cheryl

2012-03-01

This study proposes methods for blending design components of clinical effectiveness and implementation research. Such blending can provide benefits over pursuing these lines of research independently; for example, more rapid translational gains, more effective implementation strategies, and more useful information for decision makers. This study proposes a "hybrid effectiveness-implementation" typology, describes a rationale for their use, outlines the design decisions that must be faced, and provides several real-world examples. An effectiveness-implementation hybrid design is one that takes a dual focus a priori in assessing clinical effectiveness and implementation. We propose 3 hybrid types: (1) testing effects of a clinical intervention on relevant outcomes while observing and gathering information on implementation; (2) dual testing of clinical and implementation interventions/strategies; and (3) testing of an implementation strategy while observing and gathering information on the clinical intervention's impact on relevant outcomes. The hybrid typology proposed herein must be considered a construct still in evolution. Although traditional clinical effectiveness and implementation trials are likely to remain the most common approach to moving a clinical intervention through from efficacy research to public health impact, judicious use of the proposed hybrid designs could speed the translation of research findings into routine practice.

Coordinated Science Campaign Scheduling for Sensor Webs

NASA Technical Reports Server (NTRS)

Edgington, Will; Morris, Robert; Dungan, Jennifer; Williams, Jenny; Carlson, Jean; Fleming, Damian; Wood, Terri; Yorke-Smith, Neil

2005-01-01

Future Earth observing missions will study different aspects and interacting pieces of the Earth's eco-system. Scientists are designing increasingly complex, interdisciplinary campaigns to exploit the diverse capabilities of multiple Earth sensing assets. In addition, spacecraft platforms are being configured into clusters, trains, or other distributed organizations in order to improve either the quality or the coverage of observations. These simultaneous advances in the design of science campaigns and in the missions that will provide the sensing resources to support them offer new challenges in the coordination of data and operations that are not addressed by current practice. For example, the scheduling of scientific observations for satellites in low Earth orbit is currently conducted independently by each mission operations center. An absence of an information infrastructure to enable the scheduling of coordinated observations involving multiple sensors makes it difficult to execute campaigns involving multiple assets. This paper proposes a software architecture and describes a prototype system called DESOPS (Distributed Earth Science Observation Planning and Scheduling) that will address this deficiency.

Opto-mechanical design of small infrared cloud measuring device

NASA Astrophysics Data System (ADS)

Zhang, Jiao; Yu, Xun; Tao, Yu; Jiang, Xu

2018-01-01

In order to make small infrared cloud measuring device can be well in a wide temperature range and day-night environment, a design idea using catadioptric infrared panoramic imaging optical system and simple mechanical structure for realizing observation clode under all-weather conditions was proposed. Firstly, the optical system of cloud measuring device was designed. An easy-to-use numerical method was proposed to acquire the profile of a catadioptric mirror, which brought the property of equidistance projection and played the most important role in a catadioptric panoramic lens. Secondly, the mechanical structure was studied in detail. Overcoming the limitations of traditional primary mirror support structure, integrative design was used for refractor and mirror support structure. Lastly, temperature adaptability and modes of the mirror support structure were analyzed. Results show that the observation range of the cloud measuring device is wide and the structure is simple, the fundamental frequency of the structure is greater than 100 Hz, the surface precision of the system reflector reaches PV of λ/10 and RMS of λ/40under the load of temperature range - 40 60°C, it can meet the needs of existing meteorological observation.

X-ray polarization capabilities of a small explorer mission

NASA Astrophysics Data System (ADS)

Jahoda, Keith M.; Black, J. Kevin; Hill, Joanne E.; Kallman, Timothy R.; Kaaret, Philip E.; Markwardt, Craig B.; Okajima, Takashi; Petre, Robert; Soong, Yang; Strohmayer, Tod E.; Tamagawa, Toru; Tawara, Yuzuru

2014-07-01

X-ray polarization measurements hold great promise for studying the geometry and emission mechanisms in the strong gravitational and magnetic fields that surround black holes and neutron stars. In spite of this, the observational situation remains very limited; the last instrument dedicated to X-ray polarimetry flew decades ago on OSO-8, and the few recent measurements have been made by instruments optimized for other purposes. However, the technical capabilities to greatly advance the observational situation are in hand. Recent developments in micro-pattern gas detectors allow use of the polarization sensitivity of the photo-electric effect, which is the dominant interaction in the band above 2 keV. We present the scientific and technical requirements for an X-ray polarization observatory consistent with the scope of a NASA Small Explorer (SMEX) mission, along with a representative catalog of what the observational capabilities and expected sensitivities for the first year of operation could be. The mission is based on the technically robust design of the Gravity and Extreme Magnetism SMEX (GEMS) which completed a Phase B study and Preliminary Design Review in 2012. The GEMS mission is enabled by time projection detectors sensitive to the photo-electric effect. Prototype detectors have been designed, and provide engineering and performance data which support the mission design. The detectors are further characterized by low background, modest spectral resolution, and sub-millisecond timing resolution. The mission also incorporates high efficiency grazing incidence X-ray mirrors, design features that reduce systematic errors (identical telescopes at different azimuthal angles with respect to the look axis, and mounted on a rotating spacecraft platform), and a moderate capability to perform Target of Opportunity observations. The mission operates autonomously in a low earth, low inclination orbit with one to ten downlinks per day and one or more uplinks per week. Data and calibration products will be made available through the High Energy Astrophysics Science and Archival Research Center (HEASARC).

An Analysis of the Quality Assurance Policies in a Ghanian University

ERIC Educational Resources Information Center

Seniwoliba, Joseph Attiah; Yakubu, Richard Nalarb

2015-01-01

The study examined the implementation challenges of quality assurance in public universities in Ghana with a focus on University for Development Studies (UDS). The study adopted a qualitative case study design. The data for the study was collected through in-depth interviews, document analysis and participants observation. The study revealed that…

Diffusion Filters for Variational Data Assimilation of Sea Surface Temperature in an Intermediate Climate Model

DTIC Science & Technology

2015-01-01

over data-dense regions. After that, a perfect twin data assimilation experiment framework is designed to study the effect of the GDF on the state...is designed to study the effect of the GDF on the state estimation based on an intermediate coupled model. In this framework, the assimilation model...observation. Considering = , (4) is equal to () = 1 2 + 1 2 ( − ) −1 ( − ) . (5) The effect of in (5) can

Evidence mapping of whole grain intervention studies, health outcomes, and reporting practices

USDA-ARS?s Scientific Manuscript database

Higher consumption of whole grain foods is associated with reduced risk of cardiovascular disease, diabetes, and obesity in observational studies; yet, in intervention studies, the effect of whole grains on intermediate markers of risk are mixed. This may be due to the variability in study design, d...

The state of the art and future opportunities for using longitudinal n-of-1 methods in health behaviour research: a systematic literature overview.

PubMed

McDonald, Suzanne; Quinn, Francis; Vieira, Rute; O'Brien, Nicola; White, Martin; Johnston, Derek W; Sniehotta, Falko F

2017-12-01

n-of-1 studies test hypotheses within individuals based on repeated measurement of variables within the individual over time. Intra-individual effects may differ from those found in between-participant studies. Using examples from a systematic review of n-of-1 studies in health behaviour research, this article provides a state of the art overview of the use of n-of-1 methods, organised according to key methodological considerations related to n-of-1 design and analysis, and describes future challenges and opportunities. A comprehensive search strategy (PROSPERO:CRD42014007258) was used to identify articles published between 2000 and 2016, reporting observational or interventional n-of-1 studies with health behaviour outcomes. Thirty-nine articles were identified which reported on n-of-1 observational designs and a range of n-of-1 interventional designs, including AB, ABA, ABABA, alternating treatments, n-of-1 randomised controlled trial, multiple baseline and changing criterion designs. Behaviours measured included treatment adherence, physical activity, drug/alcohol use, sleep, smoking and eating behaviour. Descriptive, visual or statistical analyses were used. We identify scope and opportunities for using n-of-1 methods to answer key questions in health behaviour research. n-of-1 methods provide the tools needed to help advance theoretical knowledge and personalise/tailor health behaviour interventions to individuals.

Clinical Knowledge from Observational Studies: Everything You Wanted to Know but Were Afraid to Ask.

PubMed

Gershon, Andrea S; Jafarzadeh, S Reza; Wilson, Kevin C; Walkey, Allan J

2018-05-07

Well-done randomized trials provide accurate estimates of treatment effect by producing groups that are similar on all measures except for the intervention of interest. However, inferences of efficacy in tightly-controlled experimental settings may not translate into similar effectiveness in real-world settings. Observational studies generally enable inferences over a wider range of patient characteristics and evaluation of a broader range of outcomes over a longer period than randomized trials. However, clinicians are often reluctant to incorporate the findings of observational studies into clinical practice. Reason for uncertainty regarding observational studies include a lack of familiarity with observational research methods, occasional disagreements between results of observational studies and randomized trials, the perceived risk of spurious results from systematic bias, and prior teaching that randomized trials are the most reliable source of medical evidence. We propose that a better understanding of observational research will enhance clinicians' ability to distinguish reliable observational studies from those that are subjected to biases and, therefore, provide more confidence to apply observational research results into clinical practice when appropriate. Herein, we explain why observational studies may be perceived as less conclusive than randomized trials, address situations in which observational research and randomized trials produced different findings, and provide information on observational study design so that quality can be evaluated. We conclude that observational research is a valuable source of medical evidence and that clinical action is strongest when supported by both high quality observational studies and randomized trials.

Reporting of methodological features in observational studies of pre-harvest food safety.

PubMed

Sargeant, Jan M; O'Connor, Annette M; Renter, David G; Kelton, David F; Snedeker, Kate; Wisener, Lee V; Leonard, Erin K; Guthrie, Alessia D; Faires, Meredith

2011-02-01

Observational studies in pre-harvest food safety may be useful for identifying risk factors and for evaluating potential mitigation strategies to reduce foodborne pathogens. However, there are no structured reporting guidelines for these types of study designs in livestock species. Our objective was to evaluate the reporting of observational studies in the pre-harvest food safety literature using guidelines modified from the human healthcare literature. We identified 100 pre-harvest food safety studies published between 1999 and 2009. Each study was evaluated independently by two reviewers using a structured checklist. Of the 38 studies that explicitly stated the observational study design, 27 were described as cross-sectional studies, eight as case-control studies, and three as cohort studies. Study features reported in over 75% of the selected studies included: description of the geographic location of the studies, definitions and sources of data for outcomes, organizational level and source of data for independent variables, description of statistical methods and results, number of herds enrolled in the study and included in the analysis, and sources of study funding. However, other features were not consistently reported, including details related to eligibility criteria for groups (such as barn, room, or pen) and individuals, numbers of groups and individuals included in various stages of the study, identification of primary outcomes, the distinction between putative risk factors and confounding variables, the identification of a primary exposure variable, the referent level for evaluation of categorical variable associations, methods of controlling confounding variables and missing variables, model fit, details of subset analysis, demographic information at the sampling unit level, and generalizability of the study results. Improvement in reporting of observational studies of pre-harvest food safety will aid research readers and reviewers in interpreting and evaluating the results of such studies. Copyright © 2010 Elsevier B.V. All rights reserved.

A PILOT STUDY TO DETERMINE THE INFLUENCE UPON TEACHERS AND UPON STUDENTS OF A TELEVISION PROGRAM DESIGNED TO PROVIDE IN-SERVICE TRAINING AND CLASSROOM INSTRUCTION IN SPANISH.

ERIC Educational Resources Information Center

HOWE, ELLIOT C.

THREE SMALL SCHOOLS IN UTAH, INCLUDING THREE TEACHERS AND THEIR SPANISH I STUDENTS, PARTICIPATED IN THIS STUDY. ONE TEACHER RECEIVED CONVENTIONAL IN-SERVICE TRAINING, THE OTHER TWO WERE GIVEN IN IN-SERVICE TRAINING IN TEACHING SPANISH AS THEY OBSERVED THE TELEVISION CLASS. ONE GROUP OF STUDENTS OBSERVED THE TELEVISION CLASS THREE TIMES PER WEEK…

Perspective: Randomized Controlled Trials Are Not a Panacea for Diet-Related Research12

PubMed Central

Hébert, James R; Frongillo, Edward A; Adams, Swann A; Turner-McGrievy, Gabrielle M; Hurley, Thomas G; Miller, Donald R; Ockene, Ira S

2016-01-01

Research into the role of diet in health faces a number of methodologic challenges in the choice of study design, measurement methods, and analytic options. Heavier reliance on randomized controlled trial (RCT) designs is suggested as a way to solve these challenges. We present and discuss 7 inherent and practical considerations with special relevance to RCTs designed to study diet: 1) the need for narrow focus; 2) the choice of subjects and exposures; 3) blinding of the intervention; 4) perceived asymmetry of treatment in relation to need; 5) temporal relations between dietary exposures and putative outcomes; 6) strict adherence to the intervention protocol, despite potential clinical counter-indications; and 7) the need to maintain methodologic rigor, including measuring diet carefully and frequently. Alternatives, including observational studies and adaptive intervention designs, are presented and discussed. Given high noise-to-signal ratios interjected by using inaccurate assessment methods in studies with weak or inappropriate study designs (including RCTs), it is conceivable and indeed likely that effects of diet are underestimated. No matter which designs are used, studies will require continued improvement in the assessment of dietary intake. As technology continues to improve, there is potential for enhanced accuracy and reduced user burden of dietary assessments that are applicable to a wide variety of study designs, including RCTs. PMID:27184269

The areal reduction factor: A new analytical expression for the Lazio Region in central Italy

NASA Astrophysics Data System (ADS)

Mineo, C.; Ridolfi, E.; Napolitano, F.; Russo, F.

2018-05-01

For the study and modeling of hydrological phenomena, both in urban and rural areas, a proper estimation of the areal reduction factor (ARF) is crucial. In this paper, we estimated the ARF from observed rainfall data as the ratio between the average rainfall occurring in a specific area and the point rainfall. Then, we compared the obtained ARF values with some of the most widespread empirical approaches in literature which are used when rainfall observations are not available. Results highlight that the literature formulations can lead to a substantial over- or underestimation of the ARF estimated from observed data. These findings can have severe consequences, especially in the design of hydraulic structures where empirical formulations are extensively applied. The aim of this paper is to present a new analytical relationship with an explicit dependence on the rainfall duration and area that can better represent the ARF-area trend over the area case of study. The analytical curve presented here can find an important application to estimate the ARF values for design purposes. The test study area is the Lazio Region (central Italy).

Immortal time bias in pharmaco-epidemiology.

PubMed

Suissa, Samy

2008-02-15

Immortal time is a span of cohort follow-up during which, because of exposure definition, the outcome under study could not occur. Bias from immortal time was first identified in the 1970s in epidemiology in the context of cohort studies of the survival benefit of heart transplantation. It recently resurfaced in pharmaco-epidemiology, with several observational studies reporting that various medications can be extremely effective at reducing morbidity and mortality. These studies, while using different cohort designs, all involved some form of immortal time and the corresponding bias. In this paper, the author describes various cohort study designs leading to this bias, quantifies its magnitude under different survival distributions, and illustrates it by using data from a cohort of lung cancer patients. The author shows that for time-based, event-based, and exposure-based cohort definitions, the bias in the rate ratio resulting from misclassified or excluded immortal time increases proportionately to the duration of immortal time. The bias is more pronounced with a decreasing hazard function for the outcome event, as illustrated with the Weibull distribution compared with a constant hazard from the exponential distribution. In conclusion, observational studies of drug benefit in which computerized databases are used must be designed and analyzed properly to avoid immortal time bias.

Distributed Space Mission Design for Earth Observation Using Model-Based Performance Evaluation

NASA Technical Reports Server (NTRS)

Nag, Sreeja; LeMoigne-Stewart, Jacqueline; Cervantes, Ben; DeWeck, Oliver

2015-01-01

Distributed Space Missions (DSMs) are gaining momentum in their application to earth observation missions owing to their unique ability to increase observation sampling in multiple dimensions. DSM design is a complex problem with many design variables, multiple objectives determining performance and cost and emergent, often unexpected, behaviors. There are very few open-access tools available to explore the tradespace of variables, minimize cost and maximize performance for pre-defined science goals, and therefore select the most optimal design. This paper presents a software tool that can multiple DSM architectures based on pre-defined design variable ranges and size those architectures in terms of predefined science and cost metrics. The tool will help a user select Pareto optimal DSM designs based on design of experiments techniques. The tool will be applied to some earth observation examples to demonstrate its applicability in making some key decisions between different performance metrics and cost metrics early in the design lifecycle.

A Case Study of a High School Fab Lab

NASA Astrophysics Data System (ADS)

Lacy, Jennifer E.

This dissertation examines making and design-based STEM education in a formal makerspace. It focuses on how the design and implementation of a Fab Lab learning environment and curriculum affect how instructors and students see themselves engaging in science, and how the Fab Lab relates to the social sorting practices that already take place at North High School. While there is research examining design-based STEM education in informal and formal learning environments, we know little about how K-12 teachers define STEM in making activities when no university or museum partnership exists. This study sought to help fill this gap in the research literature. This case study of a formal makerspace followed instructors and students in one introductory Fab Lab course for one semester. Additional observations of an introductory woodworking course helped build the case and set it into the school context, and provided supplementary material to better understand the similarities and differences between the Fab Lab course and a more traditional design-based learning course. Using evidence from observational field notes, participant interviews, course materials, and student work, I found that the North Fab Lab relies on artifacts and rhetoric symbolic of science and STEM to set itself apart from other design-based courses at North High School. Secondly, the North Fab Lab instructors and students were unable to explain how what they were doing in the Fab Lab was science, and instead relied on vague and unsupported claims related to interdisciplinary STEM practices and dated descriptions of science. Lastly, the design and implementation of the Fab Lab learning environment and curriculum and its separation from North High School's low tech, design-based courses effectively reinforced social sorting practices and cultural assumptions about student work and intelligence.

Creel survey sampling designs for estimating effort in short-duration Chinook salmon fisheries

USGS Publications Warehouse

McCormick, Joshua L.; Quist, Michael C.; Schill, Daniel J.

2013-01-01

Chinook Salmon Oncorhynchus tshawytscha sport fisheries in the Columbia River basin are commonly monitored using roving creel survey designs and require precise, unbiased catch estimates. The objective of this study was to examine the relative bias and precision of total catch estimates using various sampling designs to estimate angling effort under the assumption that mean catch rate was known. We obtained information on angling populations based on direct visual observations of portions of Chinook Salmon fisheries in three Idaho river systems over a 23-d period. Based on the angling population, Monte Carlo simulations were used to evaluate the properties of effort and catch estimates for each sampling design. All sampling designs evaluated were relatively unbiased. Systematic random sampling (SYS) resulted in the most precise estimates. The SYS and simple random sampling designs had mean square error (MSE) estimates that were generally half of those observed with cluster sampling designs. The SYS design was more efficient (i.e., higher accuracy per unit cost) than a two-cluster design. Increasing the number of clusters available for sampling within a day decreased the MSE of estimates of daily angling effort, but the MSE of total catch estimates was variable depending on the fishery. The results of our simulations provide guidelines on the relative influence of sample sizes and sampling designs on parameters of interest in short-duration Chinook Salmon fisheries.

GADICON spectrometer for ionosphere far-ultraviolet observation: prototype design, manufacturing, and testing.

PubMed

Yu, Lei

2016-08-20

The design, manufacturing, and testing of an imaging spectrometer prototype that will address new scientific requirements by the observation of the lower atmosphere's impact on the ionosphere are presented. The two sided lateral limb observation covering 130-180 nm far-ultraviolet (FUV) region allows the instrument to perform particle measurements in the daytime and nighttime. In this paper, we focus upon the working design principle, observation, and calibration.

Software Design Reviews Using the Software Architecture Analysis Method: A Case Study

DTIC Science & Technology

2000-02-01

described in Appendix G. Second, an independent research observer also attended the review. Adler (1994) claims that the age and gender of the...observer can affect how they record events. Thus, the second observer was of a different gender to the researcher, and there was a significant difference in...alternatives, when the facilitator stopped one person from dominating discussions, when the facilitator stopped people from socialising and when the

Structure Optimization of Porous Dental Implant Based on 3D Printing

NASA Astrophysics Data System (ADS)

Ji, Fangqiu; Zhang, Chunyu; Chen, Xianshuai

2018-03-01

In this paper, selective laser melting (SLM) technology is used to process complex structures. In combination with the theory of biomedicine, a porous implant with a porous structure is designed to induce bone cell growth. The mechanical strength advantage of SLM was discussed by observing the metallographic structure of SLM specimen with mechanical microscope and mechanical tensile test. The osseointegration of porous implants was observed and analyzed by biological experiments. By establishing a mechanical model, the mechanical properties of the bone implant combined with the jaw bone were studied by the simple mechanical analysis under static multi loading and the finite element mechanical analysis. According to the experimental observation and mechanical research, the optimization suggestions for the structure design of the implant made by SLM technology were put forward.

Task-based lens design with application to digital mammography

NASA Astrophysics Data System (ADS)

Chen, Liying; Barrett, Harrison H.

2005-01-01

Recent advances in model observers that predict human perceptual performance now make it possible to optimize medical imaging systems for human task performance. We illustrate the procedure by considering the design of a lens for use in an optically coupled digital mammography system. The channelized Hotelling observer is used to model human performance, and the channels chosen are differences of Gaussians. The task performed by the model observer is detection of a lesion at a random but known location in a clustered lumpy background mimicking breast tissue. The entire system is simulated with a Monte Carlo application according to physics principles, and the main system component under study is the imaging lens that couples a fluorescent screen to a CCD detector. The signal-to-noise ratio (SNR) of the channelized Hotelling observer is used to quantify this detectability of the simulated lesion (signal) on the simulated mammographic background. Plots of channelized Hotelling SNR versus signal location for various lens apertures, various working distances, and various focusing places are presented. These plots thus illustrate the trade-off between coupling efficiency and blur in a task-based manner. In this way, the channelized Hotelling SNR is used as a merit function for lens design.

Task-based lens design, with application to digital mammography

NASA Astrophysics Data System (ADS)

Chen, Liying

Recent advances in model observers that predict human perceptual performance now make it possible to optimize medical imaging systems for human task performance. We illustrate the procedure by considering the design of a lens for use in an optically coupled digital mammography system. The channelized Hotelling observer is used to model human performance, and the channels chosen are differences of Gaussians (DOGs). The task performed by the model observer is detection of a lesion at a random but known location in a clustered lumpy background mimicking breast tissue. The entire system is simulated with a Monte Carlo application according to the physics principles, and the main system component under study is the imaging lens that couples a fluorescent screen to a CCD detector. The SNR of the channelized Hotelling observer is used to quantify the detectability of the simulated lesion (signal) upon the simulated mammographic background. In this work, plots of channelized Hotelling SNR vs. signal location for various lens apertures, various working distances, and various focusing places are shown. These plots thus illustrate the trade-off between coupling efficiency and blur in a task-based manner. In this way, the channelized Hotelling SNR is used as a merit function for lens design.

An assessment of schoolyard features and behavior patterns in children's utilization and physical activity.

PubMed

Anthamatten, Peter; Brink, Lois; Kingston, Beverly; Kutchman, Eve; Lampe, Sarah; Nigg, Claudio

2014-03-01

Careful research that elucidates how behavior relates to design in the context of elementary school grounds can serve to guide cost-efficient design with the goal of encouraging physical activity (PA). This work explores patterns in children's PA behavior within playground spaces with the specific goal of guiding healthy playground design. Data on children's utilization and PA behavior in 6 playgrounds divided into 106 observation zones were collected in 2005 and 2006 at Denver elementary school playgrounds using the System for Observing Play and Leisure Activity in Youth. Analyses of variance and t tests determined whether there were differences in utilization and behavior patterns across observations zones and between genders. This study provides evidence that children prefer to use certain types of playground zones and that they are more likely to practice moderate-to-vigorous physical activity (MVPA) in some zones. The authors observed statistically significant differences between genders. Boys were more likely to engage in MVPA in zones without equipment, girls were more likely to use zones with equipment. This work suggests that the inclusion or omission of specific playground features may have an impact on the way that children use the spaces.

Behavior of sensitivities in the one-dimensional advection-dispersion equation: Implications for parameter estimation and sampling design

USGS Publications Warehouse

Knopman, Debra S.; Voss, Clifford I.

1987-01-01

The spatial and temporal variability of sensitivities has a significant impact on parameter estimation and sampling design for studies of solute transport in porous media. Physical insight into the behavior of sensitivities is offered through an analysis of analytically derived sensitivities for the one-dimensional form of the advection-dispersion equation. When parameters are estimated in regression models of one-dimensional transport, the spatial and temporal variability in sensitivities influences variance and covariance of parameter estimates. Several principles account for the observed influence of sensitivities on parameter uncertainty. (1) Information about a physical parameter may be most accurately gained at points in space and time with a high sensitivity to the parameter. (2) As the distance of observation points from the upstream boundary increases, maximum sensitivity to velocity during passage of the solute front increases and the consequent estimate of velocity tends to have lower variance. (3) The frequency of sampling must be “in phase” with the S shape of the dispersion sensitivity curve to yield the most information on dispersion. (4) The sensitivity to the dispersion coefficient is usually at least an order of magnitude less than the sensitivity to velocity. (5) The assumed probability distribution of random error in observations of solute concentration determines the form of the sensitivities. (6) If variance in random error in observations is large, trends in sensitivities of observation points may be obscured by noise and thus have limited value in predicting variance in parameter estimates among designs. (7) Designs that minimize the variance of one parameter may not necessarily minimize the variance of other parameters. (8) The time and space interval over which an observation point is sensitive to a given parameter depends on the actual values of the parameters in the underlying physical system.

WFIRST: Project Overview and Status

NASA Astrophysics Data System (ADS)

Kruk, Jeffrey; WFIRST Formulation Science Working Group, WFIRST Project Team

2018-01-01

The Wide-Field InfraRed Survey Telescope (WFIRST) will be the next Astrophysics flagship mission to follow JWST. The observatory payload consists of a Hubble-size telescope aperture with a wide-field NIR instrument and a coronagraph operating at visible wavelengths and employing state-of-the-art wavefront sensing and control. The Wide-field instrument is optimized for large area NIR imaging and spectroscopic surveys, with performance requirements driven by programs to study cosmology and exoplanet detection via gravitational microlensing. All data will be public immediately, and a substantial guest observer program will be supported.The WFIRST Project is presently in Phase A, with a transition to Phase B expected in early to mid 2018. Candidate observing programs are under detailed study in order to inform the mission design, but the actual science investigations will not be selected until much closer to launch. We will present an overview of the present mission design and expected performance, a summary of Project status, and plans for selecting the observing programs.

Further observations on soil freezing in the Pacific Northwest.

Treesearch

Charles E. Hale

1951-01-01

Frost observations during the winter and spring of 1949-1950 indicated that pronounced soil freezing conditions existed in the ponderosa pine, lodgepole pine, grass and brush types in eastern Oregon and Washington. Accordingly, a study was designed to determine the occurrence and character of frost under these widespread forest and range types. This paper presents a...

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

ERIC Educational Resources Information Center

Calderon, Carlos Trevino

2012-01-01

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

Video Modeling and Observational Learning to Teach Gaming Access to Students with ASD

ERIC Educational Resources Information Center

Spriggs, Amy D.; Gast, David L.; Knight, Victoria F.

2016-01-01

The purpose of this study was to evaluate both video modeling and observational learning to teach age-appropriate recreation and leisure skills (i.e., accessing video games) to students with autism spectrum disorder. Effects of video modeling were evaluated via a multiple probe design across participants and criteria for mastery were based on…

Polychronometry: The Study of Time Variables in Behavior.

ERIC Educational Resources Information Center

Mackey, William Francis

There is a growing need for instrumentation which can enable us to observe and compute phenomena that take place in time. Although problems of observation, computation, interpretation and categorization vary from field to field and from problem to problem, it is possible to design an instrument for use in any situation where time-variables have to…

An Evaluation of the Effectiveness of an Automated Observation and Feedback System on Safe Sitting Postures

ERIC Educational Resources Information Center

Yu, Eunjeong; Moon, Kwangsu; Oah, Shezeen; Lee, Yohaeng

2013-01-01

This study evaluated the effectiveness of an automated observation and feedback system in improving safe sitting postures. Participants were four office workers. The dependent variables were the percentages of time participants spent in five safe body positions during experimental sessions. We used a multiple-baseline design counterbalanced across…

Some Bullies Are More Equal than Others: Peer Relationships Modulate Altruistic Punishment of Bullies after Observing Ostracism

ERIC Educational Resources Information Center

Güroglu, Berna; Will, Geert-Jan; Klapwijk, Eduard T.

2013-01-01

The current study presents a novel experimental design to examine how "real-life" peer relationships modulate altruistic punishment of bullies and compensation of victims after "observed" ostracism. Twenty-four participants (age 20) were invited to an experimental session in groups of three classmates and two unfamiliar peers,…

The Differential Impact of Observational Learning and Practice-Based Learning on the Development of Oral Presentation Skills in Higher Education

ERIC Educational Resources Information Center

De Grez, Luc; Valcke, Martin; Roozen, Irene

2014-01-01

The present study focuses on the design and evaluation of an innovative instructional approach to developing oral presentation skills. The intervention builds on the observational learning theoretical perspective. This perspective is contrasted with the traditional training and practice approach. Two sequencing approaches--learners starting with…

[Patients' perspective and economic variables as objectives in clinical trials: added value to clinical parameters].

PubMed

Bovaira-García, M J; Soler-Company, E

2012-01-01

Patient-reported outcome (PRO) measures complement traditional biomedical outcome measures. The purpose of this study was to evaluate the use of PRO measures including health-related quality of life (HRQoL) questionnaires as a measurement of efficacy and the frequency of inclusion of economic variables related to direct and indirect costs in the design of clinical trials and phase IV observational studies. Moreover, for the trials quality score were measured, and if there were any relationship between the quality study design score and the PRO inclusion. Retrospective observational study of the clinical trials and phase IV observational studies approved by a Clinical Research Ethics Committee (2008-2010). We gathered data concerning general aspects including medical specialty, pathology, methodological quality based on Jadad scale (0-5), inclusion of PRO and economic variables. For clinical trials including HRQoL measurements, we analysed the type of questionnaire in use. Where there were no HRQoL measurements, we analysed if their inclusion would have been proper or not. A total of 70 protocols (59 CTs and 11 phase IV observational studies) were analysed; 37 (52.8%) included PRO measures, and 3 protocols (4.3%) used them as a primary endpoint. Data analysis by therapeutic area showed that PRO measures were most commonly studied in the fields of endocrinology, neurology, digestive diseases, and cardiology. The average quality score for the trials was 2.8. The trials with more PRO inclusion in their end points had a significantly higher quality score. Only 13 (22%) clinical trials and 2 (18.2%) phase IV observational studies included economic variables. The emergence of economic variables in clinical trials and phase IV observational studies evaluated was low, however, more than half of the revised protocols have included PRO measures, reflecting the importance of these parameters in the assessment of the effectiveness of drug treatments, although its use is still not systematic. Copyright © 2011 SECA. Published by Elsevier Espana. All rights reserved.

Virtual Reality as Innovative Approach to the Interior Designing

NASA Astrophysics Data System (ADS)

Kaleja, Pavol; Kozlovská, Mária

2017-06-01

We can observe significant potential of information and communication technologies (ICT) in interior designing field, by development of software and hardware virtual reality tools. Using ICT tools offer realistic perception of proposal in its initial idea (the study). A group of real-time visualization, supported by hardware tools like Oculus Rift HTC Vive, provides free walkthrough and movement in virtual interior with the possibility of virtual designing. By improving of ICT software tools for designing in virtual reality we can achieve still more realistic virtual environment. The contribution presented proposal of an innovative approach of interior designing in virtual reality, using the latest software and hardware ICT virtual reality technologies

Initial studies of middle and upper tropospheric stratiform clouds

NASA Technical Reports Server (NTRS)

Cox, S. K.

1982-01-01

The spatial and temporal occurrence of cloud layers, the development of a physical-numerical model to simulate the life cycles of tropospheric cloud layers, and the design of an observational program to study the properties of these layers are described.

Diesel Exhaust in Miners Study: Q&A

Cancer.gov

The Diesel Exhaust in Miners Study was designed to evaluate the risk of death associated with diesel exhaust exposure, particularly as it may relate to lung cancer. The researchers observed increased risk for lung cancer death with increasing levels of ex

Where to find weather and climatic data for forest research studies and management planning.

Treesearch

Donald A. Haines

1977-01-01

Forest-range research or operational study designs should include the possible effects of weather and climate. This document describes the meteorological observational networks, the data available from them, and where the information is stored.

Assessment of the quality of reporting observational studies in the pediatric dental literature.

PubMed

Butani, Yogita; Hartz, Arthur; Levy, Steven; Watkins, Catherine; Kanellis, Michael; Nowak, Arthur

2006-01-01

The purpose of this assessment was to evaluate reporting of observational studies in the pediatric dental literature. This assessment included the following steps: (1) developing a model for reporting information in clinical dentistry studies; (2) identifying treatment comparisons in pediatric dentistry that were evaluated by at least 5 observational studies; (3) abstracting from these studies any data indicated by applying the reporting model; and (4) comparing available data elements to the desired data elements in the reporting model. The reporting model included data elements related to: (1) patients; (2) providers; (3) treatment details; and (4) study design. Two treatment comparisons in pediatric dentistry were identified with 5 or more observational studies: (1) stainless steel crowns vs amalgams (10 studies); and (2) composite restorations vs amalgam (5 studies). Results from studies comparing the same treatments varied substantially. Data elements from the reporting model that could have explained some of the variation were often reported inadequately or not at all. Reporting of observational studies in the pediatric dental literature may be inadequate for an informed interpretation of the results. Models similar to that used in this study could be used for developing standards for the conduct and reporting of observational studies in pediatric dentistry.

A sensitivity analysis for missing outcomes due to truncation by death under the matched-pairs design.

PubMed

Imai, Kosuke; Jiang, Zhichao

2018-04-29

The matched-pairs design enables researchers to efficiently infer causal effects from randomized experiments. In this paper, we exploit the key feature of the matched-pairs design and develop a sensitivity analysis for missing outcomes due to truncation by death, in which the outcomes of interest (e.g., quality of life measures) are not even well defined for some units (e.g., deceased patients). Our key idea is that if 2 nearly identical observations are paired prior to the randomization of the treatment, the missingness of one unit's outcome is informative about the potential missingness of the other unit's outcome under an alternative treatment condition. We consider the average treatment effect among always-observed pairs (ATOP) whose units exhibit no missing outcome regardless of their treatment status. The naive estimator based on available pairs is unbiased for the ATOP if 2 units of the same pair are identical in terms of their missingness patterns. The proposed sensitivity analysis characterizes how the bounds of the ATOP widen as the degree of the within-pair similarity decreases. We further extend the methodology to the matched-pairs design in observational studies. Our simulation studies show that informative bounds can be obtained under some scenarios when the proportion of missing data is not too large. The proposed methodology is also applied to the randomized evaluation of the Mexican universal health insurance program. An open-source software package is available for implementing the proposed research. Copyright © 2018 John Wiley & Sons, Ltd.

Clinical audit of emergency unit before and after establishment of the emergency medicine department.

PubMed

Amini, Afshin; Dindoost, Payam; Moghimi, Mehrdad; Kariman, Hamid; Shahrami, Ali; Dolatabadi, Ali Arhami; Ali-Mohammadi, Hossein; Alavai-Moghaddam, Mostafa; Derakhshanfar, Hojjat; Hatamabadi, HamidReza; Heidari, Kamran; Alamdari, Shahram; Meibodi, Mohammad Kalantar; Shojaee, Majid; Foroozanfar, Mohammad Mehdi; Hashemi, Behrooz; Sabzeghaba, Anita; Kabir, Ali

2012-02-01

To assess the deficiencies and potential areas through a medical audit of the emergency departments, in six general hospitals affiliated to Shahid Beheshti University of Medical Sciences at Tehran, Iran, after preparing specific wards-based international standards. A checklist was completed for all hospitals which met our eligibility criteria mainly observation and interviews with head nurses and managers of the emergency medicine unit of the hospitals before (2003) and after (2008) the establishment of emergency departments there. Domains studied included staffing, education and continuing professional development (CPD), facility (design), equipment, ancillary services, medical records, manuals and references, research, administration, pre-hospital care, information systems, disaster planning, bench-marking and hospital accreditation. Education and CPD (p = 0.042), design and facility (p = 0.027), equipment (p = 0.028), and disaster (p = 0.026) had significantly improved after the establishment of emergency departments. Nearly all domains showed a positive change though it was non-significant in a few. In terms of observation, better improvement was seen in disaster, security, design, and research. According to the score for each domain compared to what it was in the earlier phase, better improvement was observed in hospital accreditation, information systems, security, disaster planning, and research. Security, disaster planning, research, design and facility had improved in hospitals that wave studied, while equipment, records, ancillary services, administration and bench-marking had the lowest improvement even after the establishment of emergency department, and, hence, needed specific attention.

Conceptual design and structural analysis of the spectroscopy of the atmosphere using far infrared emission (SAFIRE) instrument

NASA Technical Reports Server (NTRS)

Moses, Robert W.; Averill, Robert D.

1992-01-01

The conceptual design and structural analysis for the Spectroscopy of the Atmosphere using Far Infrared Emission (SAFIRE) Instrument are provided. SAFIRE, which is an international effort, is proposed for the Earth Observing Systems (EOS) program for atmospheric ozone studies. A concept was developed which meets mission requirements and is the product of numerous parametric studies and design/analysis iterations. Stiffness, thermal stability, and weight constraints led to a graphite/epoxy composite design for the optical bench and supporting struts. The structural configuration was determined by considering various mounting arrangements of the optical, cryo, and electronic components. Quasi-static, thermal, modal, and dynamic response analyses were performed, and the results are presented for the selected configuration.

Daylight Design for Urban Residential Planning in Poland in Regulations and in A Practice. A Comparison Study of Daylight Conditions Observed in the Four Neighbouring Residential Areas

NASA Astrophysics Data System (ADS)

Sokol, Natalia; Martyniuk-Peczek, Justyna

2017-10-01

This paper reports on the partial results of the research aiming to illustrate how an integration of daylight design into an architectural planning process can help designers to create the residential buildings in respect to the environmental issues, solar and illuminance gains, as well as, the residents’ needs and comfort. It describes how changing daylight recommendations affected the design of the block of flats regarding their orientation, the spacing, the forms, and the size of the windows in the four urban residential areas. The results of this study help to determine more precise characterization of daylight indicators useful in architectural planning.

Distributed Cognition in a Sixth-Grade Classroom: An Attempt to Overcome Alternative Conceptions about Light and Color

ERIC Educational Resources Information Center

Valanides, Nicos; Angeli, Charoula

2008-01-01

In this study, we discuss the scaffolded design of ODRES (Observe, Discuss, and Reason with Evidence in Science), a computer tool that was designed to be used with elementary school children in science, and report on the effects of learning with ODRES on students' conceptual understandings about light, color, and vision. Succinctly, dyads of…

The Validity and Value of Peer Assessment Using Adaptive Comparative Judgement in Design Driven Practical Education

ERIC Educational Resources Information Center

Seery, Niall; Canty, Donal; Phelan, Pat

2012-01-01

This paper presents the response of the technology teacher education programmes at the University of Limerick to the assessment challenge created by the shift in philosophy of the Irish national curriculum from a craft-based focus to design-driven education. This study observes two first year modules of the undergraduate programmes that focused on…

Exploring the Design, Development and Use of Websites through Accessibility and Usability Studies

ERIC Educational Resources Information Center

Foley, Alan

2011-01-01

In this paper, data obtained from a university website accessibility and usability validation process are analyzed and used to demonstrate how the design process can affect the online experience for users with disabilities. Interviews, observations, and use data (e.g. where users clicked on a page or what path taken through a site) were collected.…

The dependability of medical students' performance ratings as documented on in-training evaluations.

PubMed

van Barneveld, Christina

2005-03-01

To demonstrate an approach to obtain an unbiased estimate of the dependability of students' performance ratings during training, when the data-collection design includes nesting of student in rater, unbalanced nest sizes, and dependent observations. In 2003, two variance components analyses of in-training evaluation (ITE) report data were conducted using urGENOVA software. In the first analysis, the dependability for the nested and unbalanced data-collection design was calculated. In the second analysis, an approach using multiple generalizability studies was used to obtain an unbiased estimate of the student variance component, resulting in an unbiased estimate of dependability. Results suggested that there is bias in estimates of the dependability of students' performance on ITEs that are attributable to the data-collection design. When the bias was corrected, the results indicated that the dependability of ratings of student performance was almost zero. The combination of the multiple generalizability studies method and the use of specialized software provides an unbiased estimate of the dependability of ratings of student performance on ITE scores for data-collection designs that include nesting of student in rater, unbalanced nest sizes, and dependent observations.

Cross-modal links among vision, audition, and touch in complex environments.

PubMed

Ferris, Thomas K; Sarter, Nadine B

2008-02-01

This study sought to determine whether performance effects of cross-modal spatial links that were observed in earlier laboratory studies scale to more complex environments and need to be considered in multimodal interface design. It also revisits the unresolved issue of cross-modal cuing asymmetries. Previous laboratory studies employing simple cues, tasks, and/or targets have demonstrated that the efficiency of processing visual, auditory, and tactile stimuli is affected by the modality, lateralization, and timing of surrounding cues. Very few studies have investigated these cross-modal constraints in the context of more complex environments to determine whether they scale and how complexity affects the nature of cross-modal cuing asymmetries. Amicroworld simulation of battlefield operations with a complex task set and meaningful visual, auditory, and tactile stimuli was used to investigate cuing effects for all cross-modal pairings. Significant asymmetric performance effects of cross-modal spatial links were observed. Auditory cues shortened response latencies for collocated visual targets but visual cues did not do the same for collocated auditory targets. Responses to contralateral (rather than ipsilateral) targets were faster for tactually cued auditory targets and each visual-tactile cue-target combination, suggesting an inhibition-of-return effect. The spatial relationships between multimodal cues and targets significantly affect target response times in complex environments. The performance effects of cross-modal links and the observed cross-modal cuing asymmetries need to be examined in more detail and considered in future interface design. The findings from this study have implications for the design of multimodal and adaptive interfaces and for supporting attention management in complex, data-rich domains.

Recent progress in DNA origami technology.

PubMed

Endo, Masayuki; Sugiyama, Hiroshi

2011-06-01

DNA origami is an emerging technology for designing defined two-dimensional DNA nanostructures. In this review, we focus on and describe several types of DNA origami-related studies, as follows: (1) programmed DNA origami assembly, (2) DNA origami-templated molecular assembly, (3) design and construction of various three-dimensional DNA origami structures, (4) programmed functionalization of DNA origami and combination with top-down nanotechnology, (5) single molecular observation on a designed DNA origami, and (6) DNA nanomachines working on a DNA origami. © 2011 by John Wiley & Sons, Inc.

Design considerations to enhance the safety of patient compartments in ambulance transporters.

PubMed

Byran, Eyal; Gilad, Issachar

2012-01-01

The safety of the interior of ambulances is dubious and, in the event of sudden impact during emergency transport, potentially perilous to patients they carry. The workplace ergonomics of the interior of the passenger cabin is lacking. This article discusses an improved ergonomic interior design based on study findings, observations and subjective perception. It suggests design aspects and safety concepts aimed at increasing the safety of patients and paramedic staff inside the ambulance as a mobile workstation.

On some properties of bone functional adaptation phenomenon useful in mechanical design.

PubMed

Nowak, Michał

2010-01-01

The paper discusses some unique properties of trabecular bone functional adaptation phenomenon, useful in mechanical design. On the basis of the biological process observations and the principle of constant strain energy density on the surface of the structure, the generic structural optimisation system has been developed. Such approach allows fulfilling mechanical theorem for the stiffest design, comprising the optimisations of size, shape and topology, using the concepts known from biomechanical studies. Also the biomimetic solution of multiple load problems is presented.

Methodology Series Module 3: Cross-sectional Studies.

PubMed

Setia, Maninder Singh

2016-01-01

Cross-sectional study design is a type of observational study design. In a cross-sectional study, the investigator measures the outcome and the exposures in the study participants at the same time. Unlike in case-control studies (participants selected based on the outcome status) or cohort studies (participants selected based on the exposure status), the participants in a cross-sectional study are just selected based on the inclusion and exclusion criteria set for the study. Once the participants have been selected for the study, the investigator follows the study to assess the exposure and the outcomes. Cross-sectional designs are used for population-based surveys and to assess the prevalence of diseases in clinic-based samples. These studies can usually be conducted relatively faster and are inexpensive. They may be conducted either before planning a cohort study or a baseline in a cohort study. These types of designs will give us information about the prevalence of outcomes or exposures; this information will be useful for designing the cohort study. However, since this is a 1-time measurement of exposure and outcome, it is difficult to derive causal relationships from cross-sectional analysis. We can estimate the prevalence of disease in cross-sectional studies. Furthermore, we will also be able to estimate the odds ratios to study the association between exposure and the outcomes in this design.

Methodology Series Module 3: Cross-sectional Studies

PubMed Central

Setia, Maninder Singh

2016-01-01

Cross-sectional study design is a type of observational study design. In a cross-sectional study, the investigator measures the outcome and the exposures in the study participants at the same time. Unlike in case–control studies (participants selected based on the outcome status) or cohort studies (participants selected based on the exposure status), the participants in a cross-sectional study are just selected based on the inclusion and exclusion criteria set for the study. Once the participants have been selected for the study, the investigator follows the study to assess the exposure and the outcomes. Cross-sectional designs are used for population-based surveys and to assess the prevalence of diseases in clinic-based samples. These studies can usually be conducted relatively faster and are inexpensive. They may be conducted either before planning a cohort study or a baseline in a cohort study. These types of designs will give us information about the prevalence of outcomes or exposures; this information will be useful for designing the cohort study. However, since this is a 1-time measurement of exposure and outcome, it is difficult to derive causal relationships from cross-sectional analysis. We can estimate the prevalence of disease in cross-sectional studies. Furthermore, we will also be able to estimate the odds ratios to study the association between exposure and the outcomes in this design. PMID:27293245

23 CFR 1340.5 - Selection of observation sites.

Code of Federal Regulations, 2013 CFR

2013-04-01

... STATE OBSERVATIONAL SURVEYS OF SEAT BELT USE Survey Design Requirements § 1340.5 Selection of... observation sites. The survey design shall include at a minimum the following protocols: (1) Protocol when...

23 CFR 1340.5 - Selection of observation sites.

Code of Federal Regulations, 2014 CFR

2014-04-01

... STATE OBSERVATIONAL SURVEYS OF SEAT BELT USE Survey Design Requirements § 1340.5 Selection of... observation sites. The survey design shall include at a minimum the following protocols: (1) Protocol when...

23 CFR 1340.5 - Selection of observation sites.

Code of Federal Regulations, 2012 CFR

2012-04-01

... STATE OBSERVATIONAL SURVEYS OF SEAT BELT USE Survey Design Requirements § 1340.5 Selection of... observation sites. The survey design shall include at a minimum the following protocols: (1) Protocol when...

Influence of implant neck design on facial bone crest dimensions in the esthetic zone analyzed by cone beam CT: a comparative study with a 5-to-9-year follow-up.

PubMed

Chappuis, Vivianne; Bornstein, Michael M; Buser, Daniel; Belser, Urs

2016-09-01

To examine the influence of two different neck designs on facial bone crest dimensions in esthetic single implant sites after a 5-to-9-year follow-up analyzed by cone beam computed tomography (CBCT). Sixty-one patients with an implant-borne single crown following early implant placement in the esthetic zone were enrolled. The test group consisted of a bone level (BL) neck design exhibiting a hydrophilic micro-rough surface combined with a platform-switching interface (PS) (n = 20). The control group comprised a soft tissue level (STL) neck design exhibiting a hydrophobic machined surface with a matching butt-joint interface (n = 41). Standardized clinical, radiologic, and esthetic parameters were applied. The facial bone crest dimensions were assessed by CBCT. Soft tissue parameters and pink esthetic scores yielded no significant differences between the two designs. Major differences were only observed at the implant shoulder level. The height of the facial bone crest for the BL design was located 0.2 mm above the implant shoulder level, whereas for the STL design, its location was 1.6 mm below. The width of the peri-implant saucer-like bone defect was reduced by 40% for the BL implant design. No differences were observed 2 mm below the shoulder level. The results of this comparative study suggest better crestal bone stability on the facial aspect of single implant sites in the esthetic zone for a BL design with a platform-switching concept when compared with STL implants with a butt-joint interface. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Co-creating value through demand and supply integration in senior industry-observations on 33 senior enterprises in Taiwan.

PubMed

Yang, Ya-Ting; Iqbal, Usman; Chen, Ya-Mei; Su, Shyi; Chang, Yao-Mao; Handa, Yujiro; Lin, Neng-Pai; Hsu, Yi-Hsin Elsa

2016-09-01

With global population aging, great business opportunities are driven by the various needs that the elderly face in everyday living. Internet development makes information spread faster, also allows elderly and their caregivers to more easily access information and actively participate in value co-creation in the services. This study aims to investigate the designs of value co-creation by the supply and demand sides of the senior industry. This study investigated senior industry in Taiwan and analyzed bussiness models of 33 selected successful senior enterprises in 2013. We adopted series field observation, reviews of documentations, analysis of meeting records and in-depth interviews with 65 CEOs and managers. Thirty-three quality enterprises in senior industry. Sixty-five CEOs and managers in 33 senior enterprises. None. Value co-creation design, value co-creating process. We constructed a conceptual model that comprehensively describes essential aspects of value co-creation and categorized the value co-creation designs into four types applying for different business models: (i) interaction in experience spaces co-creation design, (ii) on-site interacting co-creation design, (iii) social networking platform co-creation design and (iv) empowering customers co-creation design. Through value co-creation platform design, the senior enterprises have converted the originally passive roles of the elderly and caregivers into active participants in the value co-creation process. The new paradigm of value co-creation designs not only promote innovative development during the interactive process, lead enterprises reveal and meet customers' needs but also increase markets and profits. © The Author 2016. Published by Oxford University Press in association with the International Society for Quality in Health Care. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Inter-observer variability in the classification of ovarian cancer cell type using microscopy: a pilot study

NASA Astrophysics Data System (ADS)

Gavrielides, Marios A.; Ronnett, Brigitte M.; Vang, Russell; Seidman, Jeffrey D.

2015-03-01

Studies have shown that different cell types of ovarian carcinoma have different molecular profiles, exhibit different behavior, and that patients could benefit from typespecific treatment. Different cell types display different histopathology features, and different criteria are used for each cell type classification. Inter-observer variability for the task of classifying ovarian cancer cell types is an under-examined area of research. This study served as a pilot study to quantify observer variability related to the classification of ovarian cancer cell types and to extract valuable data for designing a validation study of digital pathology (DP) for this task. Three observers with expertise in gynecologic pathology reviewed 114 cases of ovarian cancer with optical microscopy, with specific guidelines for classifications into distinct cell types. For 93 cases all 3 pathologists agreed on the same cell type, for 18 cases 2 out of 3 agreed, and for 3 cases there was no agreement. Across cell types with a minimum sample size of 10 cases, agreement between all three observers was {91.1%, 80.0%, 90.0%, 78.6%, 100.0%, 61.5%} for the high grade serous carcinoma, low grade serous carcinoma, endometrioid, mucinous, clear cell, and carcinosarcoma cell types respectively. These results indicate that unanimous agreement varied over a fairly wide range. However, additional research is needed to determine the importance of these differences in comparison studies. These results will be used to aid in the design and sizing of such a study comparing optical and digital pathology. In addition, the results will help in understanding the potential role computer-aided diagnosis has in helping to improve the agreement of pathologists for this task.

DNA bipedal motor walking dynamics: an experimental and theoretical study of the dependency on step size

PubMed Central

Khara, Dinesh C; Berger, Yaron; Ouldridge, Thomas E

2018-01-01

Abstract We present a detailed coarse-grained computer simulation and single molecule fluorescence study of the walking dynamics and mechanism of a DNA bipedal motor striding on a DNA origami. In particular, we study the dependency of the walking efficiency and stepping kinetics on step size. The simulations accurately capture and explain three different experimental observations. These include a description of the maximum possible step size, a decrease in the walking efficiency over short distances and a dependency of the efficiency on the walking direction with respect to the origami track. The former two observations were not expected and are non-trivial. Based on this study, we suggest three design modifications to improve future DNA walkers. Our study demonstrates the ability of the oxDNA model to resolve the dynamics of complex DNA machines, and its usefulness as an engineering tool for the design of DNA machines that operate in the three spatial dimensions. PMID:29294083

FABRICA: A Bioreactor Platform for Printing, Perfusing, Observing, & Stimulating 3D Tissues.

PubMed

Smith, Lester J; Li, Ping; Holland, Mark R; Ekser, Burcin

2018-05-15

We are introducing the FABRICA, a bioprinter-agnostic 3D-printed bioreactor platform designed for 3D-bioprinted tissue construct culture, perfusion, observation, and analysis. The computer-designed FABRICA was 3D-printed with biocompatible material and used for two studies: (1) Flow Profile Study: perfused 5 different media through a synthetic 3D-bioprinted construct and ultrasonically analyzed the flow profile at increasing volumetric flow rates (VFR); (2) Construct Perfusion Study: perfused a 3D-bioprinted tissue construct for a week and compared histologically with a non-perfused control. For the flow profile study, construct VFR increased with increasing pump VFR. Water and other media increased VFR significantly while human and pig blood showed shallow increases. For the construct perfusion study, we confirmed more viable cells in perfused 3D-bioprinted tissue compared to control. The FABRICA can be used to visualize constructs during 3D-bioprinting, incubation, and to control and ultrasonically analyze perfusion, aseptically in real-time, making the FABRICA tunable for different tissues.

Conceptual design studies of the 5 m terahertz antenna for Dome A, Antarctica

NASA Astrophysics Data System (ADS)

Yang, Ji; Zuo, Ying-Xi; Lou, Zheng; Cheng, Jing-Quan; Zhang, Qi-Zhou; Shi, Sheng-Cai; Huang, Jia-Sheng; Yao, Qi-Jun; Wang, Zhong

2013-12-01

As the highest, coldest and driest place in Antarctica, Dome A provides exceptionally good observing conditions for ground-based observations over terahertz wavebands. The 5 m Dome A Terahertz Explorer (DATE5) has been proposed to explore new terahertz windows, primarily over wavelengths between 350 and 200 μm. DATE5 will be an open-air, fully-steerable telescope that can function by unmanned operation with remote control. The telescope will be able to endure the harsh polar environment, including high altitude, very low temperature and very low air pressure. The unique specifications, including high accuracies for surface shape and pointing and fully automatic year-around remote operation, along with a stringent limit on the periods of on-site assembly, testing and maintenance, bring a number of challenges to the design, construction, assembly and operation of this telescope. This paper introduces general concepts related to the design of the DATE5 antenna. Beginning from an overview of the environmental and operational limitations, the design specifications and requirements of the DATE5 antenna are listed. From these, major aspects on the conceptual design studies, including the antenna optics, the backup structure, the panels, the subreflector, the mounting and the antenna base structure, are explained. Some critical issues of performance are justified through analyses that use computational fluid dynamics, thermal analysis and de-icing studies, and the proposed approaches for test operation and on-site assembly. Based on these studies, we conclude that the specifications of the DATE5 antenna can generally be met by using enhanced technological approaches.

Embedding clinical interventions into observational studies.

PubMed

Newman, Anne B; Avilés-Santa, M Larissa; Anderson, Garnet; Heiss, Gerardo; Howard, Wm James; Krucoff, Mitchell; Kuller, Lewis H; Lewis, Cora E; Robinson, Jennifer G; Taylor, Herman; Treviño, Roberto P; Weintraub, William

2016-01-01

Novel approaches to observational studies and clinical trials could improve the cost-effectiveness and speed of translation of research. Hybrid designs that combine elements of clinical trials with observational registries or cohort studies should be considered as part of a long-term strategy to transform clinical trials and epidemiology, adapting to the opportunities of big data and the challenges of constrained budgets. Important considerations include study aims, timing, breadth and depth of the existing infrastructure that can be leveraged, participant burden, likely participation rate and available sample size in the cohort, required sample size for the trial, and investigator expertise. Community engagement and stakeholder (including study participants) support are essential for these efforts to succeed. Copyright © 2015. Published by Elsevier Inc.

Clinical outcomes research in gynecologic oncology.

PubMed

Melamed, Alexander; Rauh-Hain, J Alejandro; Schorge, John O

2017-09-01

Clinical outcomes research seeks to understand the real-world manifestations of clinical care. In particular, outcomes research seeks to reveal the effects of pharmaceutical, procedural, and structural aspects of healthcare on patient outcomes, including mortality, disease control, toxicity, cost, and quality of life. Although outcomes research can utilize interventional study designs, insightful use of observational data is a defining feature of this field. Many questions in gynecologic oncology are not amenable to investigation in randomized clinical trials due to cost, feasibility, or ethical concerns. When a randomized trial is not practical or has not yet been conducted, well-designed observational studies have the potential to provide the best available evidence about the effects of clinical care. Such studies may use surveys, medical records, disease registries, and a variety of administrative data sources. Even when a randomized trial has been conducted, observational studies can be used to estimate the real-world effect of an intervention, which may differ from the results obtained in the controlled setting of a clinical trial. This article reviews the goals, methodologies, data sources, and limitations of clinical outcomes research, with a focus on gynecologic oncology. Copyright © 2017. Published by Elsevier Inc.

Innovative research methods for studying treatments for rare diseases: methodological review.

PubMed

Gagne, Joshua J; Thompson, Lauren; O'Keefe, Kelly; Kesselheim, Aaron S

2014-11-24

To examine methods for generating evidence on health outcomes in patients with rare diseases. Methodological review of existing literature. PubMed, Embase, and Academic Search Premier searched for articles describing innovative approaches to randomized trial design and analysis methods and methods for conducting observational research in patients with rare diseases. We assessed information related to the proposed methods, the specific rare disease being studied, and outcomes from the application of the methods. We summarize methods with respect to their advantages in studying health outcomes in rare diseases and provide examples of their application. We identified 46 articles that proposed or described methods for studying patient health outcomes in rare diseases. Articles covered a wide range of rare diseases and most (72%) were published in 2008 or later. We identified 16 research strategies for studying rare disease. Innovative clinical trial methods minimize sample size requirements (n=4) and maximize the proportion of patients who receive active treatment (n=2), strategies crucial to studying small populations of patients with limited treatment choices. No studies describing unique methods for conducting observational studies in patients with rare diseases were identified. Though numerous studies apply unique clinical trial designs and considerations to assess patient health outcomes in rare diseases, less attention has been paid to innovative methods for studying rare diseases using observational data. © Gagne et al 2014.

Teaching childbirth with high-fidelity simulation. Is it better observing the scenario during the briefing session?

PubMed

Cuerva, Marcos J; Piñel, Carlos S; Martin, Lourdes; Espinosa, Jose A; Corral, Octavio J; Mendoza, Nicolás

2018-02-12

The design of optimal courses for obstetric undergraduate teaching is a relevant question. This study evaluates two different designs of simulator-based learning activity on childbirth with regard to respect to the patient, obstetric manoeuvres, interpretation of cardiotocography tracings (CTG) and infection prevention. This randomised experimental study which differs in the content of their briefing sessions consisted of two groups of undergraduate students, who performed two simulator-based learning activities on childbirth. The first briefing session included the observations of a properly performed scenario according to Spanish clinical practice guidelines on care in normal childbirth by the teachers whereas the second group did not include the observations of a properly performed scenario, and the students observed it only after the simulation process. The group that observed a properly performed scenario after the simulation obtained worse grades during the simulation, but better grades during the debriefing and evaluation. Simulator use in childbirth may be more fruitful when the medical students observe correct performance at the completion of the scenario compared to that at the start of the scenario. Impact statement What is already known on this subject? There is a scarcity of literature about the design of optimal high-fidelity simulation training in childbirth. It is known that preparing simulator-based learning activities is a complex process. Simulator-based learning includes the following steps: briefing, simulation, debriefing and evaluation. The most important part of high-fidelity simulations is the debriefing. A good briefing and simulation are of high relevance in order to have a fruitful debriefing session. What do the results of this study add? Our study describes a full simulator-based learning activity on childbirth that can be reproduced in similar facilities. The findings of this study add that high-fidelity simulation training in childbirth is favoured by a short briefing session and an abrupt start to the scenario, rather than a long briefing session that includes direct instruction in the scenario. What are the implications of these findings for clinical practice and/or further research? The findings of this study reveal what to include in the briefing of simulator-based learning activities on childbirth. These findings have implications in medical teaching and in medical practice.

23 CFR 1340.13 - Annual reporting requirements.

Code of Federal Regulations, 2013 CFR

2013-04-01

... survey design, alternate observation site selected subsequent to the original survey design), and by... survey design that was approved by NHTSA, in writing, as conforming to the Uniform Criteria for State Observational Surveys of Seat Belt Use, 23 CFR Part 1340; (3) The survey design has remained unchanged since the...

23 CFR 1340.13 - Annual reporting requirements.

Code of Federal Regulations, 2012 CFR

2012-04-01

... survey design, alternate observation site selected subsequent to the original survey design), and by... survey design that was approved by NHTSA, in writing, as conforming to the Uniform Criteria for State Observational Surveys of Seat Belt Use, 23 CFR Part 1340; (3) The survey design has remained unchanged since the...

23 CFR 1340.13 - Annual reporting requirements.

Code of Federal Regulations, 2014 CFR

2014-04-01

... survey design, alternate observation site selected subsequent to the original survey design), and by... survey design that was approved by NHTSA, in writing, as conforming to the Uniform Criteria for State Observational Surveys of Seat Belt Use, 23 CFR Part 1340; (3) The survey design has remained unchanged since the...

Autonomous Observational Platforms for Ocean Studies: Operation, Advantages of Sensor Technology and Data Management

NASA Astrophysics Data System (ADS)

Atamanchuk, D.; Lai, J.; Vining, M.; Kehoe, D.; Siddall, G.; Send, U.; Wallace, D.

2016-02-01

Ocean Science and Technology research group (CERC.OCEAN) at Dalhousie University focuses on new approaches in design and development of autonomous platforms to study biogeochemical and ecological changes in the world's oceans. The principal research regions included the Labrador Sea, the Northwest Atlantic between Halifax and Bermuda, and the coastal areas of Atlantic Canada. The need for improved constraints on the ocean's present and future carbon cycle is of high relevance for the Northwest Atlantic, which is recognized as a largest sink of carbon dioxide(CO2) through air-sea exchange and subsequent transport to deeper layers of the global ocean. With the use of novel sensor technology integrated into the designed platforms we are achieving a superior spatial and temporal resolution of observations. SeaCycler - a surface piercing mooring - was designed to endure year-long measurements in harsh conditions of the open ocean, like Labrador Sea, while making daily profiles of the upper 150m of the water column. Significant research efforts within CERC.OCEAN are dedicated for improving sensors' data outcome. This includes testing, calibration of the sensors, QC and postprocessing to assure reliable and trustworthy measurements. Examples and implication of the data from SeaCycler, and other platforms including buoys, and automonous Volunteer Observing Ship (VOS) flow-through system will be presented.

Conceptual and statistical issues in couples observational research: Rationale and methods for design decisions.

PubMed

Baucom, Brian R W; Leo, Karena; Adamo, Colin; Georgiou, Panayiotis; Baucom, Katherine J W

2017-12-01

Observational behavioral coding methods are widely used for the study of relational phenomena. There are numerous guidelines for the development and implementation of these methods that include principles for creating new and adapting existing coding systems as well as principles for creating coding teams. While these principles have been successfully implemented in research on relational phenomena, the ever expanding array of phenomena being investigated with observational methods calls for a similar expansion of these principles. Specifically, guidelines are needed for decisions that arise in current areas of emphasis in couple research including observational investigation of related outcomes (e.g., relationship distress and psychological symptoms), the study of change in behavior over time, and the study of group similarities and differences in the enactment and perception of behavior. This article describes conceptual and statistical considerations involved in these 3 areas of research and presents principle- and empirically based rationale for design decisions related to these issues. A unifying principle underlying these guidelines is the need for careful consideration of fit between theory, research questions, selection of coding systems, and creation of coding teams. Implications of (mis)fit for the advancement of theory are discussed. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

An observational study of the accuracy and completeness of an anesthesia information management system: recommendations for documentation system changes.

PubMed

Wilbanks, Bryan A; Moss, Jacqueline A; Berner, Eta S

2013-08-01

Anesthesia information management systems must often be tailored to fit the environment in which they are implemented. Extensive customization necessitates that systems be analyzed for both accuracy and completeness of documentation design to ensure that the final record is a true representation of practice. The purpose of this study was to determine the accuracy of a recently installed system in the capture of key perianesthesia data. This study used an observational design and was conducted using a convenience sample of nurse anesthetists. Observational data of the nurse anesthetists'delivery of anesthesia care were collected using a touch-screen tablet computer utilizing an Access database customized observational data collection tool. A questionnaire was also administered to these nurse anesthetists to assess perceived accuracy, completeness, and satisfaction with the electronic documentation system. The major sources of data not documented in the system were anesthesiologist presence (20%) and placement of intravenous lines (20%). The major sources of inaccuracies in documentation were gas flow rates (45%), medication administration times (30%), and documentation of neuromuscular function testing (20%)-all of the sources of inaccuracies were related to the use of charting templates that were not altered to reflect the actual interventions performed.

Evaluation on surface current observing network of high frequency ground wave radars in the Gulf of Thailand

NASA Astrophysics Data System (ADS)

Yin, Xunqiang; Shi, Junqiang; Qiao, Fangli

2018-05-01

Due to the high cost of ocean observation system, the scientific design of observation network becomes much important. The current network of the high frequency radar system in the Gulf of Thailand has been studied using a three-dimensional coastal ocean model. At first, the observations from current radars have been assimilated into this coastal model and the forecast results have improved due to the data assimilation. But the results also show that further optimization of the observing network is necessary. And then, a series of experiments were carried out to assess the performance of the existing high frequency ground wave radar surface current observation system. The simulated surface current data in three regions were assimilated sequentially using an efficient ensemble Kalman filter data assimilation scheme. The experimental results showed that the coastal surface current observation system plays a positive role in improving the numerical simulation of the currents. Compared with the control experiment without assimilation, the simulation precision of surface and subsurface current had been improved after assimilated the surface currents observed at current networks. However, the improvement for three observing regions was quite different and current observing network in the Gulf of Thailand is not effective and a further optimization is required. Based on these evaluations, a manual scheme has been designed by discarding the redundant and inefficient locations and adding new stations where the performance after data assimilation is still low. For comparison, an objective scheme based on the idea of data assimilation has been obtained. Results show that all the two schemes of observing network perform better than the original network and optimal scheme-based data assimilation is much superior to the manual scheme that based on the evaluation of original observing network in the Gulf of Thailand. The distributions of the optimal network of radars could be a useful guidance for future design of observing system in this region.

A Practical, Robust Methodology for Acquiring New Observation Data Using Computationally Expensive Groundwater Models

NASA Astrophysics Data System (ADS)

Siade, Adam J.; Hall, Joel; Karelse, Robert N.

2017-11-01

Regional groundwater flow models play an important role in decision making regarding water resources; however, the uncertainty embedded in model parameters and model assumptions can significantly hinder the reliability of model predictions. One way to reduce this uncertainty is to collect new observation data from the field. However, determining where and when to obtain such data is not straightforward. There exist a number of data-worth and experimental design strategies developed for this purpose. However, these studies often ignore issues related to real-world groundwater models such as computational expense, existing observation data, high-parameter dimension, etc. In this study, we propose a methodology, based on existing methods and software, to efficiently conduct such analyses for large-scale, complex regional groundwater flow systems for which there is a wealth of available observation data. The method utilizes the well-established d-optimality criterion, and the minimax criterion for robust sampling strategies. The so-called Null-Space Monte Carlo method is used to reduce the computational burden associated with uncertainty quantification. And, a heuristic methodology, based on the concept of the greedy algorithm, is proposed for developing robust designs with subsets of the posterior parameter samples. The proposed methodology is tested on a synthetic regional groundwater model, and subsequently applied to an existing, complex, regional groundwater system in the Perth region of Western Australia. The results indicate that robust designs can be obtained efficiently, within reasonable computational resources, for making regional decisions regarding groundwater level sampling.

A Community Data Model for Hydrologic Observations

NASA Astrophysics Data System (ADS)

Tarboton, D. G.; Horsburgh, J. S.; Zaslavsky, I.; Maidment, D. R.; Valentine, D.; Jennings, B.

2006-12-01

The CUAHSI Hydrologic Information System project is developing information technology infrastructure to support hydrologic science. Hydrologic information science involves the description of hydrologic environments in a consistent way, using data models for information integration. This includes a hydrologic observations data model for the storage and retrieval of hydrologic observations in a relational database designed to facilitate data retrieval for integrated analysis of information collected by multiple investigators. It is intended to provide a standard format to facilitate the effective sharing of information between investigators and to facilitate analysis of information within a single study area or hydrologic observatory, or across hydrologic observatories and regions. The observations data model is designed to store hydrologic observations and sufficient ancillary information (metadata) about the observations to allow them to be unambiguously interpreted and used and provide traceable heritage from raw measurements to usable information. The design is based on the premise that a relational database at the single observation level is most effective for providing querying capability and cross dimension data retrieval and analysis. This premise is being tested through the implementation of a prototype hydrologic observations database, and the development of web services for the retrieval of data from and ingestion of data into the database. These web services hosted by the San Diego Supercomputer center make data in the database accessible both through a Hydrologic Data Access System portal and directly from applications software such as Excel, Matlab and ArcGIS that have Standard Object Access Protocol (SOAP) capability. This paper will (1) describe the data model; (2) demonstrate the capability for representing diverse data in the same database; (3) demonstrate the use of the database from applications software for the performance of hydrologic analysis across different observation types.

Systematic Refinement of a Health Information Technology Time and Motion Workflow Instrument for Inpatient Nursing Care using a Standardized Interface Terminology

PubMed Central

Zhang, Yi; Monsen, Karen A; Adam, Terrence J; Pieczkiewicz, David S; Daman, Megan; Melton, Genevieve B

2011-01-01

Time and motion (T&M) studies provide an objective method to measure the expenditure of time by clinicians. While some instruments for T&M studies have been designed to evaluate health information technology (HIT), these instruments have not been designed for nursing workflow. We took an existing open source HIT T&M study application designed to evaluate physicians in the ambulatory setting and rationally adapted it through empiric observations to record nursing activities in the inpatient setting and linked this instrument to an existing interface terminology, the Omaha System. Nursing activities involved several dimensions and could include multiple activities occurring simultaneously, requiring significant instrument redesign. 94% of the activities from the study instrument mapped adequately to the Omaha System. T&M study instruments require customization in design optimize them for different environments, such as inpatient nursing, to enable optimal data collection. Interface terminologies show promise as a framework for recording and analyzing T&M study data. PMID:22195228

Survival of various implant-supported prosthesis designs following 36 months of clinical function.

PubMed

Rodriguez, A M; Orenstein, I H; Morris, H F; Ochi, S

2000-12-01

The use of endosseous dental implants to replace natural teeth lost to trauma, dental caries, or periodontal disease has become a predictable form of prosthetic treatment since gaining popularity in the early 1980s. While numerous clinical studies have focused on the survival of implants, few address the survival of different prosthesis designs. Beginning in 1991, 882 prostheses supported by more than 2,900 implants (687 patients) were placed by the Department of Veterans Affairs Dental Implant Clinical Research Group (DICRG). These prostheses were divided into five research strata based on arch location. The recommended design for each stratum was: bar-supported overdenture (maxillary completely edentulous); screw-retained hybrid denture (mandibular completely edentulous); screw-retained fixed partial denture (mandibular and maxillary posterior partially edentulous); and cemented single crown (maxillary anterior single tooth). Alternative overdenture designs were utilized in the edentulous arches when the recommended prosthesis could not be fabricated. Prosthesis success rates for the research strata were calculated for an observation time of up to 36 months following prosthesis placement. Success rates for the maxillary edentulous stratum ranged from 94.6% for the bar-retained overdenture supported by five to six fixtures to 81.8% for the cap-retained overdenture. The mandibular edentulous strata produced success rates of 98.1% for the fixed hybrid prosthesis to 91.7% for the cap-retained prosthesis. Success rates for maxillary and mandibular posterior fixed partial dentures were 94.3% and 92.6%, respectively, while the maxillary anterior single-tooth prosthesis yielded a success rate of 98.1% for the 36-month observation period. The recommended prosthesis designs investigated in this study proved to be reliable, with encouraging success rates for an observation period of 36 months following placement.

The evaluation the magnitude radiation exposure dose rate in digital radiography room design

NASA Astrophysics Data System (ADS)

Dwiyanto, Agung; Setia Budi, Wahyu; Hardiman, Gagoek

2017-12-01

This study discusses the dose rate in digital radiography room, buit according to meet the provisions of KEMENKES No.1014 / Menkes / SK / XI / 2008 and Regulation of BAPETEN No. 8 / 2011. The provisions primary concern of radiation safety, not comfort, by considering the space design. There are five aspects to consider in designing the space: functionality, comfort, security, movement activities and aesthetics. However provisions only met three aspects of the design, which are a function, security and movement activity. Therefore, it is necessary to evaluate digital radiography room in terms of its ability to control external radiation exposure to be safe and comfortable The dose rate is measured by the range of primary and secondary radiation in the observation points by using Surveymeter. All data are obtained by the preliminary survey prior to the study. Furthermore, the review of digital radiography room is done based on architectural design theory. The dose rate for recommended improvement room is recalculated using the same method as the actual room with the help of computer modeling. The result of dose rate calculation at the inner and outer part of digital radiography observation room shows that in-room dose for a week at each measuring point exceeds the allowable dose limit both for staff and public. During a week of observation, the outdoor dose at some measuring points exceeds the dose limit set by the KEMENKES No.1014 / Menkes / SK / XI / 2008 and Regulation BEPETEN No 8/2011. Meanwhile, the result of dose rate calculation in the inner and outer part of the improved digital radiography room can meet the applicable regulations better.

Light Augmentation Device: A New Surgical Tool for Improved Laparoscopic Visibility and Transillumination: Proof-of-Concept Study.

PubMed

Asti, Emanuele; Nebbia, Fabio; Sironi, Andrea; Bottino, Vincenzo; Bonitta, Gianluca; Bonavina, Luigi

2016-12-01

The light augmentation device (LAD ® ) is a new disposable tool designed to improve observation by transillumination in laparoscopic surgery. It can be introduced into the abdomen through an 11-12 mm port as a supplementary light source. The miniaturized design allows the surgeon to pick up the device with an endograsper and to place it under direct vision where needed. This proof-of-concept study demonstrated safety and efficacy of the device in the animal model.

Advanced nickel-hydrogen cell configuration study

NASA Technical Reports Server (NTRS)

Adler, E.; Perez, F.

1984-01-01

Three nickel hydrogen battery designs, individual pressure vessel (IPV), common pressure vessel (CPV), and a bipolar battery module were studied. Weight, system complexity and cost were compared for a satellite operating in a 6 hour, 5600 nautical mile orbit. The required energy storage is 52 kWh. A 25% improvement in specific energy is observed by employing a bipolar battery versus a battery comprised of hundreds of IPV's. Further weight benefits are realized by the development of light weight technologies in the bipolar design.

Corn blight review: Sampling model and ground data measurements program

NASA Technical Reports Server (NTRS)

Allen, R. D.

1972-01-01

The sampling plan involved the selection of the study area, determination of the flightline and segment sample design within the study area, and determination of a field sample design. Initial interview survey data consisting of crop species acreage and land use were collected. On all corn fields, additional information such as seed type, row direction, population, planting date, ect. were also collected. From this information, sample corn fields were selected to be observed through the growing season on a biweekly basis by county extension personnel.

Operational VGOS Scheduling

NASA Astrophysics Data System (ADS)

Searle, Anthony; Petrachenko, Bill

2016-12-01

The VLBI Global Observing System (VGOS) has been designed to take advantage of advances in data recording speeds and storage capacity, allowing for smaller and faster antennas, wider bandwidths, and shorter observation durations. Here, schedules for a ``realistic" VGOS network, frequency sequences, and expanded source lists are presented using a new source-based scheduling algorithm. The VGOS aim for continuous observations presents new operational challenges. As the source-based strategy is independent of the observing network, there are operational advantages which allow for more flexible scheduling of continuous VLBI observations. Using VieVS, simulations of several schedules are presented and compared with previous VGOS studies.

[Architecture and design of mental health institutions].

PubMed

Richter, Dirk; Hoffmann, Holger

2014-04-01

The physical environment of mental health institutions is regarded as a therapeutic agent within the treatment. There is only little scientific evidence on the consequences of architecture and design on psychiatric patients available. A systematic review was conducted on studies from adult mental health institutions. 25 studies were included into the review. Pre-post-studies and control group conditions were predominant study designs. Randomized controlled trials were not available. Interventions reached from art installations up to entire ward renovations. Outcome indicators were rather heterogeneous, including psychopathology, behavioural observations and aggression incidents. Overwhelmingly, the studies revealed positive results of interventions into the physical environment. We found positive outcomes independent from the intervention in detail. This result should be interpreted in the light of the generally low study quality and further methodological problems. © Georg Thieme Verlag KG Stuttgart · New York.

Observations of the Earth's magnetic field from the Space Station: Measurement at high and extremely low altitude using Space Station-controlled free-flyers

NASA Technical Reports Server (NTRS)

Webster, W., Jr.; Frawley, J. J.; Stefanik, M.

1984-01-01

Simulation studies established that the main (core), crustal and electrojet components of the Earth's magnetic field can be observed with greater resolution or over a longer time-base than is presently possible by using the capabilities provided by the space station. Two systems are studied. The first, a large lifetime, magnetic monitor would observe the main field and its time variation. The second, a remotely-piloted, magnetic probe would observe the crustal field at low altitude and the electrojet field in situ. The system design and the scientific performance of these systems is assessed. The advantages of the space station are reviewed.

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

PubMed

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

2013-04-08

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

Does Childhood Anxiety Evoke Maternal Control? A Genetically Informed Study

ERIC Educational Resources Information Center

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

2010-01-01

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

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

PubMed

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

2018-06-01

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

Multiple category-lot quality assurance sampling: a new classification system with application to schistosomiasis control.

PubMed

Olives, Casey; Valadez, Joseph J; Brooker, Simon J; Pagano, Marcello

2012-01-01

Originally a binary classifier, Lot Quality Assurance Sampling (LQAS) has proven to be a useful tool for classification of the prevalence of Schistosoma mansoni into multiple categories (≤10%, >10 and <50%, ≥50%), and semi-curtailed sampling has been shown to effectively reduce the number of observations needed to reach a decision. To date the statistical underpinnings for Multiple Category-LQAS (MC-LQAS) have not received full treatment. We explore the analytical properties of MC-LQAS, and validate its use for the classification of S. mansoni prevalence in multiple settings in East Africa. We outline MC-LQAS design principles and formulae for operating characteristic curves. In addition, we derive the average sample number for MC-LQAS when utilizing semi-curtailed sampling and introduce curtailed sampling in this setting. We also assess the performance of MC-LQAS designs with maximum sample sizes of n=15 and n=25 via a weighted kappa-statistic using S. mansoni data collected in 388 schools from four studies in East Africa. Overall performance of MC-LQAS classification was high (kappa-statistic of 0.87). In three of the studies, the kappa-statistic for a design with n=15 was greater than 0.75. In the fourth study, where these designs performed poorly (kappa-statistic less than 0.50), the majority of observations fell in regions where potential error is known to be high. Employment of semi-curtailed and curtailed sampling further reduced the sample size by as many as 0.5 and 3.5 observations per school, respectively, without increasing classification error. This work provides the needed analytics to understand the properties of MC-LQAS for assessing the prevalance of S. mansoni and shows that in most settings a sample size of 15 children provides a reliable classification of schools.

21 CFR 201.57 - Specific requirements on content and format of labeling for human prescription drug and...

Code of Federal Regulations, 2013 CFR

2013-04-01

... comparative rates of occurrence cannot be reliably determined (e.g., adverse reactions were observed only in... in vivo study designs or results (e.g., drug interaction studies), may be included in this section if...

21 CFR 201.57 - Specific requirements on content and format of labeling for human prescription drug and...

Code of Federal Regulations, 2012 CFR

2012-04-01

... comparative rates of occurrence cannot be reliably determined (e.g., adverse reactions were observed only in... in vivo study designs or results (e.g., drug interaction studies), may be included in this section if...

21 CFR 201.57 - Specific requirements on content and format of labeling for human prescription drug and...

Code of Federal Regulations, 2014 CFR

2014-04-01

... comparative rates of occurrence cannot be reliably determined (e.g., adverse reactions were observed only in... in vivo study designs or results (e.g., drug interaction studies), may be included in this section if...

Playing for Climate Change: An Educational Alternative Realty Game (ARG) in Second Life

NASA Astrophysics Data System (ADS)

Law, Sandra Kim

Learner engagement in the learning process is a challenge faced by educators, instructional designers, administrators and policy makers (Barab, Sadler, Heiselt, & Zuiker, 2007b; Van Eck, 2006). One area in which learner engagement is particularly problematic is science education; participation rates in sciences at the post-secondary level are significantly lower than in other disciplines (Fox & Stephan, 2001; Industry Canada, 2007; Kennepohl, 2009). Learners who are enrolled in science programs at postsecondary institutions also have deficits in their scientific illiteracy, specifically in their ability to understand the language of science and evaluate scientific claims in journal articles and reports. This design-based research study represents the first phase of an ongoing project exploring the role that digital educational games designed to support knowledge building within small groups can play in addressing issues of engagement and literacy in science education. A set of game design principles derived from the existing literature was used to inform the development of a prototype of the game. The prototype was evaluated by a group (N=18) of educational technology graduate students at a local university. As this was a first phase of a study in a field (i.e. game-based learning) that is still contested, it is felt that qualitative research methods can provide a representative view of the effectiveness of the game design principles and types of interactions observed between players as well as between players and artefacts in environment. The data collection methods used in this study included participant observation, data player characteristics survey, interviews, and content analysis. The final products of this study are game design principles and a game prototype. Data gathered from this study will be used to inform the design of the next version of the game, and future research in the area of digital game design and implementation (e.g., learning analytics, inoperability of the game on different MUVEs, future implementations of the game). This research demonstrated that digital educational games developed in MUVEs have the potential to support scientific literacy and higher level cognition (e.g., reflection, knowledge synthesis).

Observations of Periodic Comet 2P/Encke: Physical Properties of the Nucleus and First Visual-Wavelength Detection of Its Dust Trail

NASA Technical Reports Server (NTRS)

Lowry, Stephen C.; Weissman, Paul R.; Sykes, Mark V.; Reach, William T.

2003-01-01

We are conducting an observational program designed to determine the overall distributions of size, shape, rotation period, and surface characteristics of cometary nuclei. Here, we present results from a study of the Jupiter- family comet 2P/Encke based on observations from Steward Observatory's 2.3m Bok Telescope at Kitt Peak. This comet has been observed extensively in the past and was one of the primary flyby targets of the recently failed CONTOUR mission.

High-Speed Laser Image Analysis of Plume Angles for Pressurised Metered Dose Inhalers: The Effect of Nozzle Geometry.

PubMed

Chen, Yang; Young, Paul M; Murphy, Seamus; Fletcher, David F; Long, Edward; Lewis, David; Church, Tanya; Traini, Daniela

2017-04-01

The aim of this study is to investigate aerosol plume geometries of pressurised metered dose inhalers (pMDIs) using a high-speed laser image system with different actuator nozzle materials and designs. Actuators made from aluminium, PET and PTFE were manufactured with four different nozzle designs: cone, flat, curved cone and curved flat. Plume angles and spans generated using the designed actuator nozzles with four solution-based pMDI formulations were imaged using Oxford Lasers EnVision system and analysed using EnVision Patternate software. Reduced plume angles for all actuator materials and nozzle designs were observed with pMDI formulations containing drug with high co-solvent concentration (ethanol) due to the reduced vapour pressure. Significantly higher plume angles were observed with the PTFE flat nozzle across all formulations, which could be a result of the nozzle geometry and material's hydrophobicity. The plume geometry of pMDI aerosols can be influenced by the vapour pressure of the formulation, nozzle geometries and actuator material physiochemical properties.