Science.gov

Sample records for observational studies methods

  1. Studying Triggers for Interest and Engagement Using Observational Methods

    ERIC Educational Resources Information Center

    Renninger, K. Ann; Bachrach, Jessica E.

    2015-01-01

    In this article, we discuss the contribution of observational methods to understanding the processes involved in triggering interest and establishing engagement. We begin by reviewing the literatures on interest and engagement, noting their similarities, differences, and the utility to each of better understanding the triggering process. We then…

  2. An Observational Analysis of Coaching Behaviors for Career Development Event Teams: A Mixed Methods Study

    ERIC Educational Resources Information Center

    Ball, Anna L.; Bowling, Amanda M.; Sharpless, Justin D.

    2016-01-01

    School Based Agricultural Education (SBAE) teachers can use coaching behaviors, along with their agricultural content knowledge to help their Career Development Event (CDE) teams succeed. This mixed methods, collective case study observed three SBAE teachers preparing multiple CDEs throughout the CDE season. The teachers observed had a previous…

  3. Methods Evolved by Observation

    ERIC Educational Resources Information Center

    Montessori, Maria

    2016-01-01

    Montessori's idea of the child's nature and the teacher's perceptiveness begins with amazing simplicity, and when she speaks of "methods evolved," she is unveiling a methodological system for observation. She begins with the early childhood explosion into writing, which is a familiar child phenomenon that Montessori has written about…

  4. Generalizing Observational Study Results: Applying Propensity Score Methods to Complex Surveys

    PubMed Central

    DuGoff, Eva H; Schuler, Megan; Stuart, Elizabeth A

    2014-01-01

    ObjectiveTo provide a tutorial for using propensity score methods with complex survey data. Data SourcesSimulated data and the 2008 Medical Expenditure Panel Survey. Study DesignUsing simulation, we compared the following methods for estimating the treatment effect: a naïve estimate (ignoring both survey weights and propensity scores), survey weighting, propensity score methods (nearest neighbor matching, weighting, and subclassification), and propensity score methods in combination with survey weighting. Methods are compared in terms of bias and 95 percent confidence interval coverage. In Example 2, we used these methods to estimate the effect on health care spending of having a generalist versus a specialist as a usual source of care. Principal FindingsIn general, combining a propensity score method and survey weighting is necessary to achieve unbiased treatment effect estimates that are generalizable to the original survey target population. ConclusionsPropensity score methods are an essential tool for addressing confounding in observational studies. Ignoring survey weights may lead to results that are not generalizable to the survey target population. This paper clarifies the appropriate inferences for different propensity score methods and suggests guidelines for selecting an appropriate propensity score method based on a researcher’s goal. PMID:23855598

  5. Reporting quality of statistical methods in surgical observational studies: protocol for systematic review.

    PubMed

    Wu, Robert; Glen, Peter; Ramsay, Tim; Martel, Guillaume

    2014-06-28

    Observational studies dominate the surgical literature. Statistical adjustment is an important strategy to account for confounders in observational studies. Research has shown that published articles are often poor in statistical quality, which may jeopardize their conclusions. The Statistical Analyses and Methods in the Published Literature (SAMPL) guidelines have been published to help establish standards for statistical reporting.This study will seek to determine whether the quality of statistical adjustment and the reporting of these methods are adequate in surgical observational studies. We hypothesize that incomplete reporting will be found in all surgical observational studies, and that the quality and reporting of these methods will be of lower quality in surgical journals when compared with medical journals. Finally, this work will seek to identify predictors of high-quality reporting. This work will examine the top five general surgical and medical journals, based on a 5-year impact factor (2007-2012). All observational studies investigating an intervention related to an essential component area of general surgery (defined by the American Board of Surgery), with an exposure, outcome, and comparator, will be included in this systematic review. Essential elements related to statistical reporting and quality were extracted from the SAMPL guidelines and include domains such as intent of analysis, primary analysis, multiple comparisons, numbers and descriptive statistics, association and correlation analyses, linear regression, logistic regression, Cox proportional hazard analysis, analysis of variance, survival analysis, propensity analysis, and independent and correlated analyses. Each article will be scored as a proportion based on fulfilling criteria in relevant analyses used in the study. A logistic regression model will be built to identify variables associated with high-quality reporting. A comparison will be made between the scores of surgical

  6. Generalizing observational study results: applying propensity score methods to complex surveys.

    PubMed

    Dugoff, Eva H; Schuler, Megan; Stuart, Elizabeth A

    2014-02-01

    To provide a tutorial for using propensity score methods with complex survey data. Simulated data and the 2008 Medical Expenditure Panel Survey. Using simulation, we compared the following methods for estimating the treatment effect: a naïve estimate (ignoring both survey weights and propensity scores), survey weighting, propensity score methods (nearest neighbor matching, weighting, and subclassification), and propensity score methods in combination with survey weighting. Methods are compared in terms of bias and 95 percent confidence interval coverage. In Example 2, we used these methods to estimate the effect on health care spending of having a generalist versus a specialist as a usual source of care. In general, combining a propensity score method and survey weighting is necessary to achieve unbiased treatment effect estimates that are generalizable to the original survey target population. Propensity score methods are an essential tool for addressing confounding in observational studies. Ignoring survey weights may lead to results that are not generalizable to the survey target population. This paper clarifies the appropriate inferences for different propensity score methods and suggests guidelines for selecting an appropriate propensity score method based on a researcher's goal. © Health Research and Educational Trust.

  7. Do observational studies using propensity score methods agree with randomized trials? A systematic comparison of studies on acute coronary syndromes

    PubMed Central

    Dahabreh, Issa J.; Sheldrick, Radley C.; Paulus, Jessica K.; Chung, Mei; Varvarigou, Vasileia; Jafri, Haseeb; Rassen, Jeremy A.; Trikalinos, Thomas A.; Kitsios, Georgios D.

    2012-01-01

    Aims Randomized controlled trials (RCTs) are the gold standard for assessing the efficacy of therapeutic interventions because randomization protects from biases inherent in observational studies. Propensity score (PS) methods, proposed as a potential solution to confounding of the treatment–outcome association, are widely used in observational studies of therapeutic interventions for acute coronary syndromes (ACS). We aimed to systematically assess agreement between observational studies using PS methods and RCTs on therapeutic interventions for ACS. Methods and results We searched for observational studies of interventions for ACS that used PS methods to estimate treatment effects on short- or long-term mortality. Using a standardized algorithm, we matched observational studies to RCTs based on patients’ characteristics, interventions, and outcomes (‘topics’), and we compared estimates of treatment effect between the two designs. When multiple observational studies or RCTs were identified for the same topic, we performed a meta-analysis and used the summary relative risk for comparisons. We matched 21 observational studies investigating 17 distinct clinical topics to 63 RCTs (median = 3 RCTs per observational study) for short-term (7 topics) and long-term (10 topics) mortality. Estimates from PS analyses differed statistically significantly from randomized evidence in two instances; however, observational studies reported more extreme beneficial treatment effects compared with RCTs in 13 of 17 instances (P = 0.049). Sensitivity analyses limited to large RCTs, and using alternative meta-analysis models yielded similar results. Conclusion For the treatment of ACS, observational studies using PS methods produce treatment effect estimates that are of more extreme magnitude compared with those from RCTs, although the differences are rarely statistically significant. PMID:22711757

  8. Comparison of methods of extracting information for meta-analysis of observational studies in nutritional epidemiology.

    PubMed

    Bae, Jong-Myon

    2016-01-01

    A common method for conducting a quantitative systematic review (QSR) for observational studies related to nutritional epidemiology is the "highest versus lowest intake" method (HLM), in which only the information concerning the effect size (ES) of the highest category of a food item is collected on the basis of its lowest category. However, in the interval collapsing method (ICM), a method suggested to enable a maximum utilization of all available information, the ES information is collected by collapsing all categories into a single category. This study aimed to compare the ES and summary effect size (SES) between the HLM and ICM. A QSR for evaluating the citrus fruit intake and risk of pancreatic cancer and calculating the SES by using the HLM was selected. The ES and SES were estimated by performing a meta-analysis using the fixed-effect model. The directionality and statistical significance of the ES and SES were used as criteria for determining the concordance between the HLM and ICM outcomes. No significant differences were observed in the directionality of SES extracted by using the HLM or ICM. The application of the ICM, which uses a broader information base, yielded more-consistent ES and SES, and narrower confidence intervals than the HLM. The ICM is advantageous over the HLM owing to its higher statistical accuracy in extracting information for QSR on nutritional epidemiology. The application of the ICM should hence be recommended for future studies.

  9. International Halley watch amateur observers' manual for scientific comet studies. Part 1: Methods

    NASA Technical Reports Server (NTRS)

    Edberg, S. J.

    1983-01-01

    The International Halley Watch is described as well as comets and observing techniques. Information on periodic Comet Halley's apparition for its 1986 perihelion passage is provided. Instructions are given for observation projects valuable to the International Halley Watch in six areas of study: (1) visual observations; (2) photography; (3) astrometry; (4) spectroscopic observations; (5) photoelectric photometry; and (6) meteor observations.

  10. Alternative outcome definitions and their effect on the performance of methods for observational outcome studies.

    PubMed

    Reich, Christian G; Ryan, Patrick B; Schuemie, Martijn J

    2013-10-01

    A systematic risk identification system has the potential to test marketed drugs for important Health Outcomes of Interest or HOI. For each HOI, multiple definitions are used in the literature, and some of them are validated for certain databases. However, little is known about the effect of different definitions on the ability of methods to estimate their association with medical products. Alternative definitions of HOI were studied for their effect on the performance of analytical methods in observational outcome studies. A set of alternative definitions for three HOI were defined based on literature review and clinical diagnosis guidelines: acute kidney injury, acute liver injury and acute myocardial infarction. The definitions varied by the choice of diagnostic codes and the inclusion of procedure codes and lab values. They were then used to empirically study an array of analytical methods with various analytical choices in four observational healthcare databases. The methods were executed against predefined drug-HOI pairs to generate an effect estimate and standard error for each pair. These test cases included positive controls (active ingredients with evidence to suspect a positive association with the outcome) and negative controls (active ingredients with no evidence to expect an effect on the outcome). Three different performance metrics where used: (i) Area Under the Receiver Operator Characteristics (ROC) curve (AUC) as a measure of a method's ability to distinguish between positive and negative test cases, (ii) Measure of bias by estimation of distribution of observed effect estimates for the negative test pairs where the true effect can be assumed to be one (no relative risk), and (iii) Minimal Detectable Relative Risk (MDRR) as a measure of whether there is sufficient power to generate effect estimates. In the three outcomes studied, different definitions of outcomes show comparable ability to differentiate true from false control cases (AUC) and a

  11. Research Methods in Healthcare Epidemiology and Antimicrobial Stewardship-Observational Studies.

    PubMed

    Snyder, Graham M; Young, Heather; Varman, Meera; Milstone, Aaron M; Harris, Anthony D; Munoz-Price, Silvia

    2016-10-01

    Observational studies compare outcomes among subjects with and without an exposure of interest, without intervention from study investigators. Observational studies can be designed as a prospective or retrospective cohort study or as a case-control study. In healthcare epidemiology, these observational studies often take advantage of existing healthcare databases, making them more cost-effective than clinical trials and allowing analyses of rare outcomes. This paper addresses the importance of selecting a well-defined study population, highlights key considerations for study design, and offers potential solutions including biostatistical tools that are applicable to observational study designs. Infect Control Hosp Epidemiol 2016;1-6.

  12. 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

  13. Extension of Kaplan-Meier methods in observational studies with time-varying treatment.

    PubMed

    Xu, Stanley; Shetterly, Susan; Powers, David; Raebel, Marsha A; Tsai, Thomas T; Ho, P Michael; Magid, David

    2012-01-01

    Inverse probability of treatment weighted Kaplan-Meier estimates have been developed to compare two treatments in the presence of confounders in observational studies. Recently, stabilized weights were developed to reduce the influence of extreme inverse probability of treatment-weighted weights in estimating treatment effects. The objective of this research was to use adjusted Kaplan-Meier estimates and modified log-rank and Wilcoxon tests to examine the effect of a treatment that varies over time in an observational study. We proposed stabilized weight adjusted Kaplan-Meier estimates and modified log-rank and Wilcoxon tests when the treatment was time-varying over the follow-up period. We applied these new methods in examining the effect of an anti-platelet agent, clopidogrel, on subsequent events, including bleeding, myocardial infarction, and death after a drug-eluting stent was implanted into a coronary artery. In this population, clopidogrel use may change over time based on a patient's behavior (e.g., nonadherence) and physicians' recommendations (e.g., end of duration of therapy). Consequently, clopidogrel use was treated as a time-varying variable. We demonstrate that 1) the sample sizes at three chosen time points are almost identical in the original and weighted datasets; and 2) the covariates between patients on and off clopidogrel were well balanced after stabilized weights were applied to the original samples. The stabilized weight-adjusted Kaplan-Meier estimates and modified log-rank and Wilcoxon tests are useful in presenting and comparing survival functions for time-varying treatments in observational studies while adjusting for known confounders. Copyright © 2012 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  14. Observation of Interactions in Adolescent Group Therapy: A Mixed Methods Study

    PubMed Central

    Arias-Pujol, Eulàlia; Anguera, M. Teresa

    2017-01-01

    Group psychotherapy is a useful clinical practice for adolescents with mental health issues. Groups typically consist of young people of similar ages but with different personalities, and this results in a complex communication network. The goal of group psychoanalytic psychotherapy is to improve participants' mentalization abilities, facilitating interactions between peers and their therapist in a safe, containing environment. The main aim of this study was to analyze conversation turn-taking between a lead therapist, a co-therapist, and six adolescents over the course of 24 treatment sessions divided into four blocks over 8 months. We employed a mixed-methods design based on systematic observation, which we consider to be a mixed method itself, as the qualitative data collected in the initial observation phase is transformed into quantitative data and subsequently interpreted qualitatively with the aid of clinical vignettes. The observational methodology design was nomothetic, follow-up, and multidimensional. The choice of methodology is justified as we used an ad-hoc observation instrument combining a field format and a category system. Interobserver agreement was analyzed quantitatively by Cohen's kappa using the free QSEQ5 software program. Once we had confirmed the reliability of the data, these were analyzed by polar coordinate analysis, which is a powerful data reduction technique that provides a vector representation of relationships between categories. The results show significant relationships between the therapist and (1) the activation of turn-taking by the participants and the co-therapist and silence and (2) conversation-facilitating interventions and interventions designed to improve mentalization abilities. Detailed analysis of questions demonstrating interest in others showed how the communication changed from radial interactions stemming from the therapist at the beginning of therapy to circular interactions half way through. Repetition was found

  15. A mixed-methods observational study of human milk sharing communities on Facebook.

    PubMed

    Perrin, Maryanne Tigchelaar; Goodell, L Suzanne; Allen, Jonathan C; Fogleman, April

    2014-04-01

    The Food and Drug Administration discourages the casual sharing of human milk because of the risk of pathogen transmission. No information is currently available on the prevalence of this practice. The purpose of this mixed-methods observational study is to describe the size and activity of online milk sharing communities. Data for 3 months were extracted from nine public Facebook pages that facilitate the exchange of human milk. The numbers of participants, interactions, and comments were analyzed. We observed 954 individuals participating in milk sharing. The number of interactions per individual ranged from none to 16 (mean, 1.74 ± 1.65). Top reasons that participants requested milk included "lactation problems" (69.4%) and "child health problems" (48.5%). Nearly half of donors were offering 100 ounces or more, which is the minimum to be eligible to donate to nonprofit milk banks. Milk sharing networks in the United States are active, with thousands of individuals participating in the direct exchange of raw human milk. Public health issues include increasing the supply of pasteurized donor milk for fragile infants, increasing breastfeeding support, and helping milk sharing families appropriately manage risks.

  16. Last-observation-carried-forward imputation method in clinical efficacy trials: review of 352 antidepressant studies.

    PubMed

    Woolley, Stephen B; Cardoni, Alex A; Goethe, John W

    2009-12-01

    To determine the prevalence, over 40 years, of using the last-observation-carried-forward (LOCF) imputation method in clinical trials, the association between use of LOCF and how the trials were conducted, and the extent of information about attrition and LOCF use in published reports. Retrospective analysis of the reports of randomized antidepressant efficacy trials published over a 40-year period (1965-2004). MEDLINE database, Cochrane reviews, reference- and bibliography-based manual search, and publication list services. A total of 352 trials met the following criteria for analysis: antidepressant comparative efficacy trial, randomized design, patients with major depressive disorder, English-language article, published during 1965-2004, and first report of a trial. Design, attrition, and data analysis characteristics were recorded by investigators and trained assistants. Analyses included descriptive statistics of the trial size, duration, and number of patients who dropped out in LOCF versus non-LOCF studies, as well as the extent to which dropouts and the potential bias associated with attrition was discussed in the published report. The frequency of published antidepressant clinical trials increased from less than 1 trial/year (1965-1974) to 19 trials/year (1990-1994). Trials using the LOCF method were significantly larger than non-LOCF trials (p<0.01), and the proportion of subjects dropping out was significantly greater (p<0.05) in LOCF versus non-LOCF trials. The proportion of subjects dropping out remained relatively constant over time (approximately 30%) but was significantly greater among LOCF (30.9%) than non-LOCF (28.8%) trials (p<0.01). The LOCF study articles were more likely to report dropouts, but only 7% of these articles reported outcomes recorded for subjects before they dropped out. Less than 16% of articles discussed bias associated with dropouts, 6.8% discussed the direction of bias, and only about 2% suggested the magnitude of the bias

  17. Physiotherapists' perceptions of workplace competency: a mixed-methods observational study.

    PubMed

    Sturt, Rodney; Burge, Angela T; Harding, Paula; Sayer, James

    2017-06-22

    Objectives Workplace-based competency is increasingly considered fundamental to patient safety and quality healthcare. The aim of the present study was to identify and describe physiotherapists' perceptions of workplace competency. Methods The present study was a mixed-methods cross-sectional observational study. Thematic and descriptive analysis of qualitative and survey data were undertaken. Forty-six physiotherapists employed at a metropolitan acute public hospital participated in interviews or focus groups; a subgroup of 31 participants also completed an online survey. Results Five main themes were identified: (1) despite the availability of workplace learning opportunities and supports, less-experienced staff reported limited confidence; (2) assessment and feedback around workplace competency was limited, predominantly informal and unstructured, with less than half of the cohort (42%) agreeing feedback received was useful for improving their workplace skills; (3) practicing within individual scope is an important aspect of workplace competency as a physiotherapist; (4) most (81%) agreed it was important for them to self-determine their learning and development goals, and they relied primarily on informal discussion to achieve these goals; and, (5) physiotherapists felt motivated regarding workplace learning, with 97% interested in developing their workplace skills however, nearly half (45%) did not feel they had sufficient time to do so. Conclusions The perceptions of physiotherapists working in a metropolitan acute public hospital are reflected in five themes. These themes elucidate how workplace competency is supported, maintained and developed among physiotherapists in this setting. These themes also highlight key challenges of workplace learning faced by this cohort of physiotherapists and allude to methods that may assist with improving feedback mechanisms and knowledge acquisition. What is known about this topic? Studies investigating employee

  18. Understanding discharge communication behaviours in a pediatric emergency care context: a mixed methods observation study protocol.

    PubMed

    Curran, Janet A; Bishop, Andrea; Plint, Amy; MacPhee, Shannon; Zemek, Roger; Chorney, Jill; Jabbour, Mona; Porter, Stephen; Sawyer, Scott

    2017-04-17

    One of the most important transitions in the continuum of care for children is discharge to home. Optimal discharge communication between healthcare providers and caregivers (e.g., parents or other guardians) who present to the emergency department (ED) with their children is not well understood. The lack of policies and considerable variation in practice regarding discharge communication in pediatric EDs pose a quality and safety risk for children and their parents. The aim of this mixed methods study is to better understand the process and structure of discharge communication in a pediatric ED context to contribute to the design and development of discharge communication interventions. We will use surveys, administrative data and real-time video observation to characterize discharge communication for six common illness presentations in a pediatric ED: (1) asthma, (2) bronchiolitis, (3) abdominal pain, (4) fever, (5) diarrhea and vomiting, and (6) minor head injury. Participants will be recruited from one of two urban pediatric EDs in Canada. Video recordings will be analyzed using Observer XT. We will use logistic regression to identify potential demographic and visit characteristic cofounders and multivariate logistic regression to examine association between verbal and non-verbal behaviours and parent recall and comprehension. Video recording of discharge communication will provide an opportunity to capture important data such as temporality, sequence and non-verbal behaviours that might influence the communication process. Given the importance of better characterizing discharge communication to identify potential barriers and enablers, we anticipate that the findings from this study will contribute to the development of more effective discharge communication policies and interventions.

  19. Study on pixel matching method of the multi-angle observation from airborne AMPR measurements

    NASA Astrophysics Data System (ADS)

    Hou, Weizhen; Qie, Lili; Li, Zhengqiang; Sun, Xiaobing; Hong, Jin; Chen, Xingfeng; Xu, Hua; Sun, Bin; Wang, Han

    2015-10-01

    For the along-track scanning mode, the same place along the ground track could be detected by the Advanced Multi-angular Polarized Radiometer (AMPR) with several different scanning angles from -55 to 55 degree, which provides a possible means to get the multi-angular detection for some nearby pixels. However, due to the ground sample spacing and spatial footprint of the detection, the different sizes of footprints cannot guarantee the spatial matching of some partly overlap pixels, which turn into a bottleneck for the effective use of the multi-angular detected information of AMPR to study the aerosol and surface polarized properties. Based on our definition and calculation of t he pixel coincidence rate for the multi-angular detection, an effective multi-angle observation's pixel matching method is presented to solve the spatial matching problem for airborne AMPR. Assuming the shape of AMPR's each pixel is an ellipse, and the major axis and minor axis depends on the flying attitude and each scanning angle. By the definition of coordinate system and origin of coordinate, the latitude and longitude could be transformed into the Euclidian distance, and the pixel coincidence rate of two nearby ellipses could be calculated. Via the traversal of each ground pixel, those pixels with high coincidence rate could be selected and merged, and with the further quality control of observation data, thus the ground pixels dataset with multi-angular detection could be obtained and analyzed, providing the support for the multi-angular and polarized retrieval algorithm research in t he next study.

  20. 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…

  1. Studies of Trace Gas Chemical Cycles Using Observations, Inverse Methods and Global Chemical Transport Models

    NASA Technical Reports Server (NTRS)

    Prinn, Ronald G.

    2001-01-01

    For interpreting observational data, and in particular for use in inverse methods, accurate and realistic chemical transport models are essential. Toward this end we have, in recent years, helped develop and utilize a number of three-dimensional models including the Model for Atmospheric Transport and Chemistry (MATCH).

  2. An observational study of the nightside ionospheres of Mars and Venus with radio occultation methods

    SciTech Connect

    Zhang, M.H.G.; Luhmann, J.G.; Kliore, A.J.

    1990-10-01

    An analysis of Mars and Venus nightside electron density profiles obtained with radio occultation methods shows how the nightside ionospheres of both planets vary with solar zenith angle. From previous studies it is known that the dayside peak electron densities at Mars and Venus show a basic similarity in that they both exhibit Chapman layer-like behavior. In contrast, the peak altitudes at mars behave like an ideal Chapman layer on the dayside, whereas the altitude of the peak at Venus is fairly constant up to the terminator. The effect of major dust storms can also be seen in the peakmore » altitudes at Mars. All Venus nightside electron density profiles show a distinct main peak for both solar minimum and maximum, whereas many profiles from the nightside of Mars do not show any peak at all. This suggests that the electron density in the Mars nightside ionosphere is frequently too low to be detected by radio occultation. On the Pioneer Venus orbiter, disappearing ionospheres were observed near solar maximum in the in-situ data when the solar wind dynamic pressure was exceptionally high. This condition occurs because the high solar wind dynamic pressure decreases the altitude of the ionopause near the terminator below {approximately}250 km, thus reducing the normal nightward transport of dayside ionospheric plasma. On the basis of the Venus observations, one might predict that if a positive correlation of nightside peak density with dynamic pressure was found, it could mean that transport from the dayside is the only significant source for the nightside ionosphere of Mars. The lack of a correlation would imply that the precipitation source at Mars is quite variable.« less

  3. Overview of the epidemiology methods and applications: strengths and limitations of observational study designs.

    PubMed

    Colditz, Graham A

    2010-01-01

    The impact of study design on the results of medical research has long been an area of both substantial debate and a smaller body of empirical research. Examples come from many disciplines within clinical and public health research. Among the early major contributions in the 1970s was work by Mosteller and colleagues (Gilbert et al., 1997), who noted that innovations in surgery and anesthesia showed greater gains than standard therapy when nonrandomized, controlled trials were evaluated compared with the gains reported in randomized, controlled trials. More recently, we and others have evaluated the impact of design in medical and surgical research, and concluded that the mean gain comparing new therapies to established therapies was biased by study design in nonrandomized trials (Colditz et al., 1989; Miller et al., 1989). Benson and Hartz (2000) conducted a study in which they focused only on studies reported after 1985. On the basis of 136 reports of 19 diverse treatments, Benson and Hartz concluded that in only 2 of the 19 analyses did the combined data from the observational studies lie outside the 95% confidence interval for the combined data from the randomized trials. A similar study drew only on data reported from 1991 to 1995, which showed remarkably similar results among observational studies and randomized, controlled trials (Concato et al., 2000). These more recent data suggest that advancing the study design and analytic methods may reduce bias in some evaluations of medical and public health interventions. Such methods apply not only to the original studies, but also to the approaches that are taken to quantitatively combine results by using meta-analytic approaches such as random effects meta-regression, Bayesian meta-analysis, and the like (Normand, 1999). By focusing attention on thorough data analysis, design issues can be understood and their impact or bias can be estimated, on average, and then ideally accounted for in the interpretation of

  4. 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.

  5. A comparative study of sensor fault diagnosis methods based on observer for ECAS system

    NASA Astrophysics Data System (ADS)

    Xu, Xing; Wang, Wei; Zou, Nannan; Chen, Long; Cui, Xiaoli

    2017-03-01

    The performance and practicality of electronically controlled air suspension (ECAS) system are highly dependent on the state information supplied by kinds of sensors, but faults of sensors occur frequently. Based on a non-linearized 3-DOF 1/4 vehicle model, different methods of fault detection and isolation (FDI) are used to diagnose the sensor faults for ECAS system. The considered approaches include an extended Kalman filter (EKF) with concise algorithm, a strong tracking filter (STF) with robust tracking ability, and the cubature Kalman filter (CKF) with numerical precision. We propose three filters of EKF, STF, and CKF to design a state observer of ECAS system under typical sensor faults and noise. Results show that three approaches can successfully detect and isolate faults respectively despite of the existence of environmental noise, FDI time delay and fault sensitivity of different algorithms are different, meanwhile, compared with EKF and STF, CKF method has best performing FDI of sensor faults for ECAS system.

  6. Observational studies of patients in the emergency department: a comparison of 4 sampling methods.

    PubMed

    Valley, Morgan A; Heard, Kennon J; Ginde, Adit A; Lezotte, Dennis C; Lowenstein, Steven R

    2012-08-01

    We evaluate the ability of 4 sampling methods to generate representative samples of the emergency department (ED) population. We analyzed the electronic records of 21,662 consecutive patient visits at an urban, academic ED. From this population, we simulated different models of study recruitment in the ED by using 2 sample sizes (n=200 and n=400) and 4 sampling methods: true random, random 4-hour time blocks by exact sample size, random 4-hour time blocks by a predetermined number of blocks, and convenience or "business hours." For each method and sample size, we obtained 1,000 samples from the population. Using χ(2) tests, we measured the number of statistically significant differences between the sample and the population for 8 variables (age, sex, race/ethnicity, language, triage acuity, arrival mode, disposition, and payer source). Then, for each variable, method, and sample size, we compared the proportion of the 1,000 samples that differed from the overall ED population to the expected proportion (5%). Only the true random samples represented the population with respect to sex, race/ethnicity, triage acuity, mode of arrival, language, and payer source in at least 95% of the samples. Patient samples obtained using random 4-hour time blocks and business hours sampling systematically differed from the overall ED patient population for several important demographic and clinical variables. However, the magnitude of these differences was not large. Common sampling strategies selected for ED-based studies may affect parameter estimates for several representative population variables. However, the potential for bias for these variables appears small. Copyright © 2012. Published by Mosby, Inc.

  7. Acceptance of family planning methods by induced abortion seekers: An observational study over five years

    PubMed Central

    Kathpalia, S.K.

    2016-01-01

    Background Prior to legalization of abortion, induced abortions were performed in an illegal manner and that resulted in many complications hence abortion was legalized in India in 1971 and the number of induced abortions has been gradually increasing since then. One way of preventing abortions is to provide family planning services to these abortion seekers so that same is not repeated. The study was performed to find out the acceptance of contraception after abortion. Methods A prospective study was performed over a period of five years from 2010 to 2014. The study group included all the cases reporting for abortion. A proforma was filled in detail to find out the type of contraception being used before pregnancy and acceptance of contraception after abortion. The existing facilities were also evaluated. Results 1228 abortions were performed over a period of five years. 94.5% of abortions were during the first trimester. 39.9% had not used any contraceptive before, contraceptives used were natural and barrier which had high failure. The main indication for seeking abortion was failure of contraception and completion of family. 39.6% of patients accepted sterilization as a method of contraception. The existing post abortion family planning services are inadequate. Conclusion Post abortion period is one which is important to prevent subsequent abortions and family planning services after abortion need to be strengthened. PMID:26900216

  8. Acceptance of family planning methods by induced abortion seekers: An observational study over five years.

    PubMed

    Kathpalia, S K

    2016-01-01

    Prior to legalization of abortion, induced abortions were performed in an illegal manner and that resulted in many complications hence abortion was legalized in India in 1971 and the number of induced abortions has been gradually increasing since then. One way of preventing abortions is to provide family planning services to these abortion seekers so that same is not repeated. The study was performed to find out the acceptance of contraception after abortion. A prospective study was performed over a period of five years from 2010 to 2014. The study group included all the cases reporting for abortion. A proforma was filled in detail to find out the type of contraception being used before pregnancy and acceptance of contraception after abortion. The existing facilities were also evaluated. 1228 abortions were performed over a period of five years. 94.5% of abortions were during the first trimester. 39.9% had not used any contraceptive before, contraceptives used were natural and barrier which had high failure. The main indication for seeking abortion was failure of contraception and completion of family. 39.6% of patients accepted sterilization as a method of contraception. The existing post abortion family planning services are inadequate. Post abortion period is one which is important to prevent subsequent abortions and family planning services after abortion need to be strengthened.

  9. Methods and Processes of Developing the Strengthening the Reporting of Observational Studies in Epidemiology-Veterinary (STROBE-Vet) Statement.

    PubMed

    Sargeant, J M; O'Connor, A M; Dohoo, I R; Erb, H N; Cevallos, M; Egger, M; Ersbøll, A K; Martin, S W; Nielsen, L R; Pearl, D L; Pfeiffer, D U; Sanchez, J; Torrence, M E; Vigre, H; Waldner, C; Ward, M P

    2016-12-01

    Reporting of observational studies in veterinary research presents challenges that often are not addressed in published reporting guidelines. Our objective was to develop an extension of the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) statement that addresses unique reporting requirements for observational studies in veterinary medicine related to health, production, welfare, and food safety. We conducted a consensus meeting with 17 experts in Mississauga, Canada. Experts completed a premeeting survey about whether items in the STROBE statement should be modified or added to address unique issues related to observational studies in animal species with health, production, welfare, or food safety outcomes. During the meeting, each STROBE item was discussed to determine whether or not rewording was recommended, and whether additions were warranted. Anonymous voting was used to determine consensus. Six items required no modifications or additions. Modifications or additions were made to the STROBE items 1 (title and abstract), 3 (objectives), 5 (setting), 6 (participants), 7 (variables), 8 (data sources and measurement), 9 (bias), 10 (study size), 12 (statistical methods), 13 (participants), 14 (descriptive data), 15 (outcome data), 16 (main results), 17 (other analyses), 19 (limitations), and 22 (funding). The methods and processes used were similar to those used for other extensions of the STROBE statement. The use of this STROBE statement extension should improve reporting of observational studies in veterinary research by recognizing unique features of observational studies involving food-producing and companion animals, products of animal origin, aquaculture, and wildlife.

  10. Clinical effect of molecular methods in sarcoma diagnosis (GENSARC): a prospective, multicentre, observational study.

    PubMed

    Italiano, Antoine; Di Mauro, Ilaria; Rapp, Jocelyn; Pierron, Gaëlle; Auger, Nathalie; Alberti, Laurent; Chibon, Frédéric; Escande, Fabienne; Voegeli, Anne-Claire; Ghnassia, Jean-Pierre; Keslair, Frédérique; Laé, Marick; Ranchère-Vince, Dominique; Terrier, Philippe; Baffert, Sandrine; Coindre, Jean-Michel; Pedeutour, Florence

    2016-04-01

    Advances in molecular genetics of sarcoma have enabled the identification of type-specific aberrations. We aimed to assess the clinical effect of systematic implementation of molecular assays to improve sarcoma misdiagnosis. In this multicentre, observational study, we recruited patients from 32 centres of the French Sarcoma Group/Reference Network in Pathology of Sarcomas. Eligibility criteria included: biopsy or surgical resection; suspicion of: dermatofibrosarcoma protuberans (cohort 1), dedifferentiated liposarcoma (cohort 2), Ewing's sarcoma family of tumours (cohort 3), synovial sarcoma (cohort 4), alveolar rhabdomyosarcoma (cohort 5), and myxoid or round cell liposarcoma (cohort 6); review by one sarcoma-expert pathologist; availability of frozen material (except for cohort 1 of patients with dermatofibrosarcoma protuberans because anti-CD34 immunohistochemistry is performed on paraffin-embedded tissue); and patient information. For each case, the pathologist made one primary diagnosis followed by up to two differential diagnoses, based on histological characteristics only. Each diagnosis was classified as certain, probable, or possible. For each case to determine the molecular classification, we did fluorescence in-situ hybridisation on paraffin-embedded samples. We also did comparative genomic hybridisation and quantitative PCR (cohort 2) or reverse transcriptase PCR (cohorts 3-6) on frozen and paraffin-embedded samples. We made a final diagnosis based on the molecular results. The clinical effect of diagnosis correction was assessed by a board of experts. Between June 22, 2009, and Oct 30, 2012, 395 patients were enrolled in the study, of which 384 were eligible for inclusion. The diagnosis was eventually modified by molecular genetics for 53 patients: eight (16%) of 50 patients with dermatofibrosarcoma (cohort 1), seven (23%) of 30 patients with dedifferentiated liposarcoma (cohort 2), 13 (12%) of 112 with Ewing's sarcoma family of tumours (cohort 3), 16

  11. Approaches to Use of Observational Methods of a Study of Parent-Child Interaction.

    ERIC Educational Resources Information Center

    Baumrind, Diana

    The methodology discussed is used in ongoing research to contrast the effectiveness of several patterns of parental authority with the same children at different ages. The first characteristic of these methods is the use of trait and behavior ratings to assess dispositional tendencies. The construct of a dispositional trait is used to account for…

  12. Study of phase clustering method for analyzing large volumes of meteorological observation data

    NASA Astrophysics Data System (ADS)

    Volkov, Yu. V.; Krutikov, V. A.; Botygin, I. A.; Sherstnev, V. S.; Sherstneva, A. I.

    2017-11-01

    The article describes an iterative parallel phase grouping algorithm for temperature field classification. The algorithm is based on modified method of structure forming by using analytic signal. The developed method allows to solve tasks of climate classification as well as climatic zoning for any time or spatial scale. When used to surface temperature measurement series, the developed algorithm allows to find climatic structures with correlated changes of temperature field, to make conclusion on climate uniformity in a given area and to overview climate changes over time by analyzing offset in type groups. The information on climate type groups specific for selected geographical areas is expanded by genetic scheme of class distribution depending on change in mutual correlation level between ground temperature monthly average.

  13. Methods and Processes of Developing the Strengthening the Reporting of Observational Studies in Epidemiology - Veterinary (STROBE-Vet) Statement.

    PubMed

    Sargeant, J M; O'Connor, A M; Dohoo, I R; Erb, H N; Cevallos, M; Egger, M; Ersbøll, A K; Martin, S W; Nielsen, L R; Pearl, D L; Pfeiffer, D U; Sanchez, J; Torrence, M E; Vigre, H; Waldner, C; Ward, M P

    2016-11-01

    Reporting of observational studies in veterinary research presents challenges that often are not addressed in published reporting guidelines. To develop an extension of the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) statement that addresses unique reporting requirements for observational studies in veterinary medicine related to health, production, welfare, and food safety. Consensus meeting of experts. Mississauga, Canada. Seventeen experts from North America, Europe, and Australia. Experts completed a pre-meeting survey about whether items in the STROBE statement should be modified or added to address unique issues related to observational studies in animal species with health, production, welfare, or food safety outcomes. During the meeting, each STROBE item was discussed to determine whether or not rewording was recommended and whether additions were warranted. Anonymous voting was used to determine consensus. Six items required no modifications or additions. Modifications or additions were made to the STROBE items 1 (title and abstract), 3 (objectives), 5 (setting), 6 (participants), 7 (variables), 8 (data sources/measurement), 9 (bias), 10 (study size), 12 (statistical methods), 13 (participants), 14 (descriptive data), 15 (outcome data), 16 (main results), 17 (other analyses), 19 (limitations), and 22 (funding). The methods and processes used were similar to those used for other extensions of the STROBE statement. The use of this STROBE statement extension should improve reporting of observational studies in veterinary research by recognizing unique features of observational studies involving food-producing and companion animals, products of animal origin, aquaculture, and wildlife. Copyright © 2016 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  14. Stakeholders' contributions to tailored implementation programs: an observational study of group interview methods.

    PubMed

    Huntink, Elke; van Lieshout, Jan; Aakhus, Eivind; Baker, Richard; Flottorp, Signe; Godycki-Cwirko, Maciek; Jäger, Cornelia; Kowalczyk, Anna; Szecsenyi, Joachim; Wensing, Michel

    2014-12-06

    Tailored strategies to implement evidence-based practice can be generated in several ways. In this study, we explored the usefulness of group interviews for generating these strategies, focused on improving healthcare for patients with chronic diseases. Participants included at least four categories of stakeholders (researchers, quality officers, health professionals, and external stakeholders) in five countries. Interviews comprised brainstorming followed by a structured interview and focused on different chronic conditions in each country. We compared the numbers and types of strategies between stakeholder categories and between interview phases. We also determined which strategies were actually used in tailored intervention programs. In total, 127 individuals participated in 25 group interviews across five countries. Brainstorming generated 8 to 120 strategies per group; structured interviews added 0 to 55 strategies. Healthcare professionals and researchers provided the largest numbers of strategies. The type of strategies for improving healthcare practice did not differ systematically between stakeholder groups in four of the five countries. In three out of five countries, all components of the chosen intervention programs were mentioned by the group of researchers. Group interviews with different stakeholder categories produced many strategies for tailored implementation of evidence-based practice, of which the content was largely similar across stakeholder categories.

  15. Methods and processes of developing the strengthening the reporting of observational studies in epidemiology - veterinary (STROBE-Vet) statement.

    PubMed

    Sargeant, J M; O'Connor, A M; Dohoo, I R; Erb, H N; Cevallos, M; Egger, M; Ersbøll, A K; Martin, S W; Nielsen, L R; Pearl, D L; Pfeiffer, D U; Sanchez, J; Torrence, M E; Vigre, H; Waldner, C; Ward, M P

    2016-11-01

    The reporting of observational studies in veterinary research presents many challenges that often are not adequately addressed in published reporting guidelines. To develop an extension of the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) statement that addresses unique reporting requirements for observational studies in veterinary medicine related to health, production, welfare, and food safety. A consensus meeting of experts was organized to develop an extension of the STROBE statement to address observational studies in veterinary medicine with respect to animal health, animal production, animal welfare, and food safety outcomes. Consensus meeting May 11-13, 2014 in Mississauga, Ontario, Canada. Seventeen experts from North America, Europe, and Australia attended the meeting. The experts were epidemiologists and biostatisticians, many of whom hold or have held editorial positions with relevant journals. Prior to the meeting, 19 experts completed a survey about whether they felt any of the 22 items of the STROBE statement should be modified and if items should be added to address unique issues related to observational studies in animal species with health, production, welfare, or food safety outcomes. At the meeting, the participants were provided with the survey responses and relevant literature concerning the reporting of veterinary observational studies. During the meeting, each STROBE item was discussed to determine whether or not re-wording was recommended, and whether additions were warranted. Anonymous voting was used to determine whether there was consensus for each item change or addition. The consensus was that six items needed no modifications or additions. Modifications or additions were made to the STROBE items numbered: 1 (title and abstract), 3 (objectives), 5 (setting), 6 (participants), 7 (variables), 8 (data sources/measurement), 9 (bias), 10 (study size), 12 (statistical methods), 13 (participants), 14

  16. Methods and Processes of Developing the Strengthening the Reporting of Observational Studies in Epidemiology - Veterinary (STROBE-Vet) Statement.

    PubMed

    Sargeant, J M; O'Connor, A M; Dohoo, I R; Erb, H N; Cevallos, M; Egger, M; Ersbøll, A K; Martin, S W; Nielsen, L R; Pearl, D L; Pfeiffer, D U; Sanchez, J; Torrence, M E; Vigre, H; Waldner, C; Ward, M P

    2016-12-01

    The reporting of observational studies in veterinary research presents many challenges that often are not adequately addressed in published reporting guidelines. A consensus meeting of experts was organized to develop an extension of the STROBE statement to address observational studies in veterinary medicine with respect to animal health, animal production, animal welfare and food safety outcomes. The consensus meeting was held 11-13 May 2014 in Mississauga, Ontario, Canada. Seventeen experts from North America, Europe and Australia attended the meeting. The experts were epidemiologists and biostatisticians, many of whom hold or have held editorial positions with relevant journals. Prior to the meeting, 19 experts completed a survey about whether they felt any of the 22 items of the STROBE statement should be modified and whether items should be added to address unique issues related to observational studies in animal species with health, production, welfare or food safety outcomes. At the meeting, the participants were provided with the survey responses and relevant literature concerning the reporting of veterinary observational studies. During the meeting, each STROBE item was discussed to determine whether or not re-wording was recommended, and whether additions were warranted. Anonymous voting was used to determine whether there was consensus for each item change or addition. The consensus was that six items needed no modifications or additions. Modifications or additions were made to the STROBE items numbered as follows: 1 (title and abstract), 3 (objectives), 5 (setting), 6 (participants), 7 (variables), 8 (data sources/measurement), 9 (bias), 10 (study size), 12 (statistical methods), 13 (participants), 14 (descriptive data), 15 (outcome data), 16 (main results), 17 (other analyses), 19 (limitations) and 22 (funding). Published literature was not always available to support modification to, or inclusion of, an item. The methods and processes used in the

  17. Monitoring progression of clinical reasoning skills during health sciences education using the case method - a qualitative observational study.

    PubMed

    Orban, Kristina; Ekelin, Maria; Edgren, Gudrun; Sandgren, Olof; Hovbrandt, Pia; Persson, Eva K

    2017-09-11

    Outcome- or competency-based education is well established in medical and health sciences education. Curricula are based on courses where students develop their competences and assessment is also usually course-based. Clinical reasoning is an important competence, and the aim of this study was to monitor and describe students' progression in professional clinical reasoning skills during health sciences education using observations of group discussions following the case method. In this qualitative study students from three different health education programmes were observed while discussing clinical cases in a modified Harvard case method session. A rubric with four dimensions - problem-solving process, disciplinary knowledge, character of discussion and communication - was used as an observational tool to identify clinical reasoning. A deductive content analysis was performed. The results revealed the students' transition over time from reasoning based strictly on theoretical knowledge to reasoning ability characterized by clinical considerations and experiences. Students who were approaching the end of their education immediately identified the most important problem and then focused on this in their discussion. Practice knowledge increased over time, which was seen as progression in the use of professional language, concepts, terms and the use of prior clinical experience. The character of the discussion evolved from theoretical considerations early in the education to clinical reasoning in later years. Communication within the groups was supportive and conducted with a professional tone. Our observations revealed progression in several aspects of students' clinical reasoning skills on a group level in their discussions of clinical cases. We suggest that the case method can be a useful tool in assessing quality in health sciences education.

  18. Observing system simulation experiments with multiple methods

    NASA Astrophysics Data System (ADS)

    Ishibashi, Toshiyuki

    2014-11-01

    An observing System Simulation Experiment (OSSE) is a method to evaluate impacts of hypothetical observing systems on analysis and forecast accuracy in numerical weather prediction (NWP) systems. Since OSSE requires simulations of hypothetical observations, uncertainty of OSSE results is generally larger than that of observing system experiments (OSEs). To reduce such uncertainty, OSSEs for existing observing systems are often carried out as calibration of the OSSE system. The purpose of this study is to achieve reliable OSSE results based on results of OSSEs with multiple methods. There are three types of OSSE methods. The first one is the sensitivity observing system experiment (SOSE) based OSSE (SOSEOSSE). The second one is the ensemble of data assimilation cycles (ENDA) based OSSE (ENDA-OSSE). The third one is the nature-run (NR) based OSSE (NR-OSSE). These three OSSE methods have very different properties. The NROSSE evaluates hypothetical observations in a virtual (hypothetical) world, NR. The ENDA-OSSE is very simple method but has a sampling error problem due to a small size ensemble. The SOSE-OSSE requires a very highly accurate analysis field as a pseudo truth of the real atmosphere. We construct these three types of OSSE methods in the Japan meteorological Agency (JMA) global 4D-Var experimental system. In the conference, we will present initial results of these OSSE systems and their comparisons.

  19. An Observational Measure of Children's Behavioural Style: Evidence Supporting a Multi-Method Approach to Studying Temperament

    ERIC Educational Resources Information Center

    Karp, Jennifer; Serbin, Lisa A.; Stack, Dale M.; Schwartzman, Alex E.

    2004-01-01

    This study demonstrates the potential utility of the Behavioural Style Observational System (BSOS) as a new observational measure of children's behavioural style. The BSOS is an objective, short and easy to use measure that can be readily adapted to a variety of home and laboratory situations. In the present study, 160 mother-child dyads from the…

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

    PubMed Central

    Getahun, Belete; Nkosi, Zethu Zerish

    2017-01-01

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

  1. 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.

  2. 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

  3. Exploring the Current Landscape of Intravenous Infusion Practices and Errors (ECLIPSE): protocol for a mixed-methods observational study.

    PubMed

    Blandford, Ann; Furniss, Dominic; Lyons, Imogen; Chumbley, Gill; Iacovides, Ioanna; Wei, Li; Cox, Anna; Mayer, Astrid; Schnock, Kumiko; Bates, David Westfall; Dykes, Patricia C; Bell, Helen; Franklin, Bryony Dean

    2016-03-03

    Intravenous medication is essential for many hospital inpatients. However, providing intravenous therapy is complex and errors are common. 'Smart pumps' incorporating dose error reduction software have been widely advocated to reduce error. However, little is known about their effect on patient safety, how they are used or their likely impact. This study will explore the landscape of intravenous medication infusion practices and errors in English hospitals and how smart pumps may relate to the prevalence of medication administration errors. This is a mixed-methods study involving an observational quantitative point prevalence study to determine the frequency and types of errors that occur in the infusion of intravenous medication, and qualitative interviews with hospital staff to better understand infusion practices and the contexts in which errors occur. The study will involve 5 clinical areas (critical care, general medicine, general surgery, paediatrics and oncology), across 14 purposively sampled acute hospitals and 2 paediatric hospitals to cover a range of intravenous infusion practices. Data collectors will compare each infusion running at the time of data collection against the patient's medication orders to identify any discrepancies. The potential clinical importance of errors will be assessed. Quantitative data will be analysed descriptively; interviews will be analysed using thematic analysis. Ethical approval has been obtained from an NHS Research Ethics Committee (14/SC/0290); local approvals will be sought from each participating organisation. Findings will be published in peer-reviewed journals and presented at conferences for academic and health professional audiences. Results will also be fed back to participating organisations to inform local policy, training and procurement. Aggregated findings will inform the debate on costs and benefits of the NHS investing in smart pump technology, and what other changes may need to be made to ensure

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

    PubMed

    Getahun, Belete; Nkosi, Zethu Zerish

    2017-01-01

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

  5. Satisfaction of patients with directly observed treatment strategy in Addis Ababa, Ethiopia: A mixed-methods study

    PubMed Central

    Getahun, Belete; Nkosi, Zethu Zerish

    2017-01-01

    Background Directly observed treatment, short course (DOTS) strategy has been a cornerstone for Tuberculosis (TB) control programs in developing countries. However, in Ethiopia satisfaction level of patients’ with TB with the this strategy is not well understood. Therefore, the study aimed to assess the satisfaction level of patients with TB with the DOTS. Method Explanatory sequential mixed method design was carried out in Addis Ababa, Ethiopia. Interviewer-administered questionnaire with 601 patients with TB who were on follow-up was employed in the quantitative approach. In the qualitative approach telephonic-interview with 25 persons lost to follow-up and focus group discussions with 23 TB experts were conducted. Result Sixty seven percent of respondent was satisfied with the DOTS. Rural residency (AOR = 3.4, 95% CI 1.6, 7.6), having TB symptoms (AOR = 0.6, 95% CI 0.4, 0.94) and treatment supporter (AOR = 4.3, 95%CI 2.7, 6.8) were associated with satisfaction with DOTS. In qualitative finding, all persons lost to follow-up were dissatisfied while TB experts enlightened lack of evidence to affirm the satisfaction level of patients with DOTS. Explored factors contributing to satisfaction include: on time availability of health care providers, DOTS service delivery process, general condition of health care facilities, nutritional support and transportation. Conclusion DOTS is limited to satisfy patients with TB and lacks a consistent system that determines the satisfaction level of patients with TB. Therefore, DOTS strategy needs to have a system to captures patients’ satisfaction level to respond on areas that need progress to improve DOTS service quality. PMID:28182754

  6. Passive activity observation (PAO) method to estimate outdoor thermal adaptation in public space: case studies in Australian cities.

    PubMed

    Sharifi, Ehsan; Boland, John

    2018-06-18

    Outdoor thermal comfort is influenced by people's climate expectations, perceptions and adaptation capacity. Varied individual response to comfortable or stressful thermal environments results in a deviation between actual outdoor thermal activity choices and those predicted by thermal comfort indices. This paper presents a passive activity observation (PAO) method for estimating contextual limits of outdoor thermal adaptation. The PAO method determines which thermal environment result in statistically meaningful changes may occur in outdoor activity patterns, and it estimates thresholds of outdoor thermal neutrality and limits of thermal adaptation in public space based on activity observation and microclimate field measurement. Applications of the PAO method have been demonstrated in Adelaide, Melbourne and Sydney, where outdoor activities were analysed against outdoor thermal comfort indices between 2013 and 2014. Adjusted apparent temperature (aAT), adaptive predicted mean vote (aPMV), outdoor standard effective temperature (OUT_SET), physiological equivalent temperature (PET) and universal thermal comfort index (UTCI) are calculated from the PAO data. Using the PAO method, the high threshold of outdoor thermal neutrality was observed between 24 °C for optional activities and 34 °C for necessary activities (UTCI scale). Meanwhile, the ultimate limit of thermal adaptation in uncontrolled public spaces is estimated to be between 28 °C for social activities and 48 °C for necessary activities. Normalised results indicate that city-wide high thresholds for outdoor thermal neutrality vary from 25 °C in Melbourne to 26 °C in Sydney and 30 °C in Adelaide. The PAO method is a relatively fast and localised method for measuring limits of outdoor thermal adaptation and effectively informs urban design and policy making in the context of climate change.

  7. Comparison Between Doppler-Echocardiography and Uncalibrated Pulse Contour Method for Cardiac Output Measurement: A Multicenter Observational Study.

    PubMed

    Scolletta, Sabino; Franchi, Federico; Romagnoli, Stefano; Carlà, Rossella; Donati, Abele; Fabbri, Lea P; Forfori, Francesco; Alonso-Iñigo, José M; Laviola, Silvia; Mangani, Valerio; Maj, Giulia; Martinelli, Giampaolo; Mirabella, Lucia; Morelli, Andrea; Persona, Paolo; Payen, Didier

    2016-07-01

    Echocardiography and pulse contour methods allow, respectively, noninvasive and less invasive cardiac output estimation. The aim of the present study was to compare Doppler echocardiography with the pulse contour method MostCare for cardiac output estimation in a large and nonselected critically ill population. A prospective multicenter observational comparison study. The study was conducted in 15 European medicosurgical ICUs. We assessed cardiac output in 400 patients in whom an echocardiographic evaluation was performed as a routine need or for cardiocirculatory assessment. None. One echocardiographic cardiac output measurement was compared with the corresponding MostCare cardiac output value per patient, considering different ICU admission categories and clinical conditions. For statistical analysis, we used Bland-Altman and linear regression analyses. To assess heterogeneity in results of individual centers, Cochran Q, and the I statistics were applied. A total of 400 paired echocardiographic cardiac output and MostCare cardiac output measures were compared. MostCare cardiac output values ranged from 1.95 to 9.90 L/min, and echocardiographic cardiac output ranged from 1.82 to 9.75 L/min. A significant correlation was found between echocardiographic cardiac output and MostCare cardiac output (r = 0.85; p < 0.0001). Among the different ICUs, the mean bias between echocardiographic cardiac output and MostCare cardiac output ranged from -0.40 to 0.45 L/min, and the percentage error ranged from 13.2% to 47.2%. Overall, the mean bias was -0.03 L/min, with 95% limits of agreement of -1.54 to 1.47 L/min and a relative percentage error of 30.1%. The percentage error was 24% in the sepsis category, 26% in the trauma category, 30% in the surgical category, and 33% in the medical admission category. The final overall percentage error was 27.3% with a 95% CI of 22.2-32.4%. Our results suggest that MostCare could be an alternative to echocardiography to assess

  8. 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

  9. A rapid method to assess grape rust mites on leaves and observations from case studies in western Oregon vineyards

    USDA-ARS?s Scientific Manuscript database

    A rapid method for extracting eriophyoid mites was adapted from previous studies to provide growers and IPM consultants with a practical, efficient, and reliable tool to monitor for rust mites in vineyards. The rinse in bag (RIB) method allows quick extraction of mites from collected plant parts (sh...

  10. Cuff depth and continuous chest auscultation method for determination of tracheal tube insertion depth in nasal intubation: observational study.

    PubMed

    Ouchi, Kentaro; Sugiyama, Kazuna

    2016-04-01

    Incorrect endobronchial placement of the tracheal tube can lead to serious complications. Hence, it is necessary to determine the accuracy of tracheal tube positioning. Markers are included on tracheal tubes, in the process of their manufacture, as indicators of approximate intubation depth. In addition, continuous chest auscultation has been used for determining the proper position of the tube. We examined insertion depth using the cuff depth and continuous chest auscultation method (CC method), compared with insertion depth determined by the marker method, to assess the accuracy of these methods. After induction of anesthesia, tracheal intubation was performed in each patient. In the CC method, the depth of tube insertion was measured when the cuff had passed through the glottis, and again when breath sounds changed in quality; the depth of tube insertion was determined from these values. In the marker method, the depth of tube insertion was measured and determined when the marker of the tube had reached the glottis, using insertion depth according to the marker as an index. Insertion depth by the marker method was 26.6 ± 1.2 cm and by the CC method was 28.0 ± 1.2 cm (P < 0.0001). The CC method indicated a significantly greater depth than the marker method. This study determined the safe range of tracheal tube placement. Tube positions determined by the CC method were about 1 cm deeper than those determined by the marker. This information is important to prevent accidental one-lung ventilation and accidental extubation. UMIN No. UMIN000011375.

  11. Longitudinal data subject to irregular observation: A review of methods with a focus on visit processes, assumptions, and study design.

    PubMed

    Pullenayegum, Eleanor M; Lim, Lily Sh

    2016-12-01

    When data are collected longitudinally, measurement times often vary among patients. This is of particular concern in clinic-based studies, for example retrospective chart reviews. Here, typically no two patients will share the same set of measurement times and moreover, it is likely that the timing of the measurements is associated with disease course; for example, patients may visit more often when unwell. While there are statistical methods that can help overcome the resulting bias, these make assumptions about the nature of the dependence between visit times and outcome processes, and the assumptions differ across methods. The purpose of this paper is to review the methods available with a particular focus on how the assumptions made line up with visit processes encountered in practice. Through this we show that no one method can handle all plausible visit scenarios and suggest that careful analysis of the visit process should inform the choice of analytic method for the outcomes. Moreover, there are some commonly encountered visit scenarios that are not handled well by any method, and we make recommendations with regard to study design that would minimize the chances of these problematic visit scenarios arising. © The Author(s) 2014.

  12. A New Method for Partial Correction of Residual Confounding in Time-Series and Other Observational Studies.

    PubMed

    Flanders, W Dana; Strickland, Matthew J; Klein, Mitchel

    2017-05-15

    Methods exist to detect residual confounding in epidemiologic studies. One requires a negative control exposure with 2 key properties: 1) conditional independence of the negative control and the outcome (given modeled variables) absent confounding and other model misspecification, and 2) associations of the negative control with uncontrolled confounders and the outcome. We present a new method to partially correct for residual confounding: When confounding is present and our assumptions hold, we argue that estimators from models that include a negative control exposure with these 2 properties tend to be less biased than those from models without it. Using regression theory, we provide theoretical arguments that support our claims. In simulations, we empirically evaluated the approach using a time-series study of ozone effects on asthma emergency department visits. In simulations, effect estimators from models that included the negative control exposure (ozone concentrations 1 day after the emergency department visit) had slightly or modestly less residual confounding than those from models without it. Theory and simulations show that including the negative control can reduce residual confounding, if our assumptions hold. Our method differs from available methods because it uses a regression approach involving an exposure-based indicator rather than a negative control outcome to partially correct for confounding. © The Author 2017. 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.

  13. An inter-observer Ki67 reproducibility study applying two different assessment methods: on behalf of the Danish Scientific Committee of Pathology, Danish breast cancer cooperative group (DBCG).

    PubMed

    Laenkholm, Anne-Vibeke; Grabau, Dorthe; Møller Talman, Maj-Lis; Balslev, Eva; Bak Jylling, Anne Marie; Tabor, Tomasz Piotr; Johansen, Morten; Brügmann, Anja; Lelkaitis, Giedrius; Di Caterino, Tina; Mygind, Henrik; Poulsen, Thomas; Mertz, Henrik; Søndergaard, Gorm; Bruun Rasmussen, Birgitte

    2018-01-01

    In 2011, the St. Gallen Consensus Conference introduced the use of pathology to define the intrinsic breast cancer subtypes by application of immunohistochemical (IHC) surrogate markers ER, PR, HER2 and Ki67 with a specified Ki67 cutoff (>14%) for luminal B-like definition. Reports concerning impaired reproducibility of Ki67 estimation and threshold inconsistency led to the initiation of this quality assurance study (2013-2015). The aim of the study was to investigate inter-observer variation for Ki67 estimation in malignant breast tumors by two different quantification methods (assessment method and count method) including measure of agreement between methods. Fourteen experienced breast pathologists from 12 pathology departments evaluated 118 slides from a consecutive series of malignant breast tumors. The staining interpretation was performed according to both the Danish and Swedish guidelines. Reproducibility was quantified by intra-class correlation coefficient (ICC) and Lights Kappa with dichotomization of observations at the larger than (>) 20% threshold. The agreement between observations by the two quantification methods was evaluated by Bland-Altman plot. For the fourteen raters the median ranged from 20% to 40% by the assessment method and from 22.5% to 36.5% by the count method. Light's Kappa was 0.664 for observation by the assessment method and 0.649 by the count method. The ICC was 0.82 (95% CI: 0.77-0.86) by the assessment method vs. 0.84 (95% CI: 0.80-0.87) by the count method. Although the study in general showed a moderate to good inter-observer agreement according to both ICC and Lights Kappa, still major discrepancies were identified in especially the mid-range of observations. Consequently, for now Ki67 estimation is not implemented in the DBCG treatment algorithm.

  14. Asian couples in negotiation: a mixed-method observational study of cultural variations across five Asian regions.

    PubMed

    Lee, Wai-Yung; Nakamura, Shin-Ichi; Chung, Moon Ja; Chun, Young Ju; Fu, Meng; Liang, Shu-Chuan; Liu, Cui-Lian

    2013-09-01

    The purpose of this study was to explore variations in how contemporary couples from five different Asian regions negotiate disagreements. Video recordings of 50 couples (10 each from Japan, Korea, Mainland China, Taiwan, and Hong Kong) discussing unresolved disagreements provided raw data for quantitative and qualitative analyses. First, teams of coders from each region used a common protocol to make quantitative ratings of content themes and interaction patterns for couples from their own region. An interregional panel of investigators then performed in-depth qualitative reviews for half of these cases, noting cultural differences not only in observed patterns of couple behavior but also in their own perceptions of these patterns. Both quantitative and qualitative analyses revealed clear regional differences on dimensions such as overt negativity, demand-withdraw interaction, and collaboration. The qualitative results also provided a richer, more nuanced view of other (e.g., gender-linked) conflict management patterns that the quantitative analyses did not capture. Inconsistencies between qualitative and quantitative data and between the qualitative observations of investigators from different regions were most pronounced for couples from Korea and Japan, whose conflict styles were subtler and less direct than those of couples from the other regions. © FPI, Inc.

  15. Heart failure, chronic diuretic use, and increase in mortality and hospitalization: an observational study using propensity score methods

    PubMed Central

    Ahmed, Ali; Husain, Ahsan; Love, Thomas E.; Gambassi, Giovanni; Dell'Italia, Louis J.; Francis, Gary S.; Gheorghiade, Mihai; Allman, Richard M.; Meleth, Sreelatha; Bourge, Robert C.

    2008-01-01

    Aims Non-potassium-sparing diuretics are commonly used in heart failure (HF). They activate the neurohormonal system, and are potentially harmful. Yet, the long-term effects of chronic diuretic use in HF are largely unknown. We retrospectively analysed the Digitalis Investigation Group (DIG) data to determine the effects of diuretics on HF outcomes. Methods and results Propensity scores for diuretic use were calculated for each of the 7788 DIG participants using a non-parsimonious multivariable logistic regression model, and were used to match 1391 (81%) no-diuretic patients with 1391 diuretic patients. Effects of diuretics on mortality and hospitalization at 40 months of median follow-up were assessed using matched Cox regression models. All-cause mortality was 21% for no-diuretic patients and 29% for diuretic patients [hazard ratio (HR) 1.31; 95% confidence interval (CI) 1.11−1.55; P = 0.002]. HF hospitalizations occurred in 18% of no-diuretic patients and 23% of diuretic patients (HR 1.37; 95% CI 1.13−1.65; P = 0.001). Conclusion Chronic diuretic use was associated with increased long-term mortality and hospitalizations in a wide spectrum of ambulatory chronic systolic and diastolic HF patients. The findings of the current study challenge the wisdom of routine chronic use of diuretics in HF patients who are asymptomatic or minimally symptomatic without fluid retention, and are on complete neurohormonal blockade. These findings, based on a non-randomized design, need to be further studied in randomized trials. PMID:16709595

  16. Using observational methods in nursing research.

    PubMed

    Salmon, Jenny

    2015-07-08

    Observation is a research data-collection method used generally to capture the activities of participants as well as when and where things are happening in a given setting. It checks description of the phenomena against what the researcher perceives to be fact in a rich experiential context. The method's main strength is that it provides direct access to the social phenomena under consideration. It can be used quantitatively or qualitatively, depending on the research question. Challenges in using observation relate to adopting the role of participant or non-participant researcher as observer. This article discusses some of the complexities involved when nurse researchers seek to collect observational data on social processes in naturalistic settings using unstructured or structured observational methods in qualitative research methodology. A glossary of research terms is provided.

  17. The Specificity of Observational Studies in Physical Activity and Sports Sciences: Moving Forward in Mixed Methods Research and Proposals for Achieving Quantitative and Qualitative Symmetry.

    PubMed

    Anguera, M Teresa; Camerino, Oleguer; Castañer, Marta; Sánchez-Algarra, Pedro; Onwuegbuzie, Anthony J

    2017-01-01

    Mixed methods studies are been increasingly applied to a diversity of fields. In this paper, we discuss the growing use-and enormous potential-of mixed methods research in the field of sport and physical activity. A second aim is to contribute to strengthening the characteristics of mixed methods research by showing how systematic observation offers rigor within a flexible framework that can be applied to a wide range of situations. Observational methodology is characterized by high scientific rigor and flexibility throughout its different stages and allows the objective study of spontaneous behavior in natural settings, with no external influence. Mixed methods researchers need to take bold yet thoughtful decisions regarding both substantive and procedural issues. We present three fundamental and complementary ideas to guide researchers in this respect: we show why studies of sport and physical activity that use a mixed methods research approach should be included in the field of mixed methods research, we highlight the numerous possibilities offered by observational methodology in this field through the transformation of descriptive data into quantifiable code matrices, and we discuss possible solutions for achieving true integration of qualitative and quantitative findings.

  18. The Specificity of Observational Studies in Physical Activity and Sports Sciences: Moving Forward in Mixed Methods Research and Proposals for Achieving Quantitative and Qualitative Symmetry

    PubMed Central

    Anguera, M. Teresa; Camerino, Oleguer; Castañer, Marta; Sánchez-Algarra, Pedro; Onwuegbuzie, Anthony J.

    2017-01-01

    Mixed methods studies are been increasingly applied to a diversity of fields. In this paper, we discuss the growing use—and enormous potential—of mixed methods research in the field of sport and physical activity. A second aim is to contribute to strengthening the characteristics of mixed methods research by showing how systematic observation offers rigor within a flexible framework that can be applied to a wide range of situations. Observational methodology is characterized by high scientific rigor and flexibility throughout its different stages and allows the objective study of spontaneous behavior in natural settings, with no external influence. Mixed methods researchers need to take bold yet thoughtful decisions regarding both substantive and procedural issues. We present three fundamental and complementary ideas to guide researchers in this respect: we show why studies of sport and physical activity that use a mixed methods research approach should be included in the field of mixed methods research, we highlight the numerous possibilities offered by observational methodology in this field through the transformation of descriptive data into quantifiable code matrices, and we discuss possible solutions for achieving true integration of qualitative and quantitative findings. PMID:29312061

  19. Causal Methods for Observational Research: A Primer.

    PubMed

    Almasi-Hashiani, Amir; Nedjat, Saharnaz; Mansournia, Mohammad Ali

    2018-04-01

    The goal of many observational studies is to estimate the causal effect of an exposure on an outcome after adjustment for confounders, but there are still some serious errors in adjusting confounders in clinical journals. Standard regression modeling (e.g., ordinary logistic regression) fails to estimate the average effect of exposure in total population in the presence of interaction between exposure and covariates, and also cannot adjust for time-varying confounding appropriately. Moreover, stepwise algorithms of the selection of confounders based on P values may miss important confounders and lead to bias in effect estimates. Causal methods overcome these limitations. We illustrate three causal methods including inverse-probability-of-treatment-weighting (IPTW) and parametric g-formula, with an emphasis on a clever combination of these 2 methods: targeted maximum likelihood estimation (TMLE) which enjoys a double-robust property against bias. © 2018 The Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

  20. Work organization in hospital wards and nurses' emotional exhaustion: A multi-method study of observation-based assessment and nurses' self-reports.

    PubMed

    Stab, Nicole; Hacker, Winfried; Weigl, Matthias

    2016-09-01

    Ward organization is a major determinant for nurses' well-being on the job. The majority of previous research on this relationship is based on single source methods, which have been criticized as skewed estimations mainly due to subjectivity of the ratings and due to common source bias. To investigate the association of ward organization characteristics and nurses' exhaustion by combining observation-based assessments with nurses' self-reports. Cross-sectional study on 25 wards of four hospitals and 245 nurses. Our multi-method approach to evaluate hospital ward organization consisted of on-site observations with a standardized assessment tool and of questionnaires to evaluate nurses' self-reports and exhaustion. After establishing the reliability of our measures, we applied multi-level regression analyses to determine associations between determinant and outcome variables. We found substantial convergence in ward organization between the observation-based assessments and nurses' self-reports, which supports the validity of our external assessments. Furthermore, two observation-based characteristics, namely participation and patient-focused care, were significantly associated with lower emotional exhaustion among the nurses. Our results suggest that observation-based assessments are a valid and feasible way to assess ward organization in hospitals. Nurses' self-reported as well as observation-based ratings on ward organization were associated with nurses' emotional exhaustion. This is of interest mainly for identifying alternative measures in evaluating nurses' work environments, to inform health promotion activities and to evaluate job redesign intervention. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. BONNSAI: correlated stellar observables in Bayesian methods

    NASA Astrophysics Data System (ADS)

    Schneider, F. R. N.; Castro, N.; Fossati, L.; Langer, N.; de Koter, A.

    2017-02-01

    In an era of large spectroscopic surveys of stars and big data, sophisticated statistical methods become more and more important in order to infer fundamental stellar parameters such as mass and age. Bayesian techniques are powerful methods because they can match all available observables simultaneously to stellar models while taking prior knowledge properly into account. However, in most cases it is assumed that observables are uncorrelated which is generally not the case. Here, we include correlations in the Bayesian code Bonnsai by incorporating the covariance matrix in the likelihood function. We derive a parametrisation of the covariance matrix that, in addition to classical uncertainties, only requires the specification of a correlation parameter that describes how observables co-vary. Our correlation parameter depends purely on the method with which observables have been determined and can be analytically derived in some cases. This approach therefore has the advantage that correlations can be accounted for even if information for them are not available in specific cases but are known in general. Because the new likelihood model is a better approximation of the data, the reliability and robustness of the inferred parameters are improved. We find that neglecting correlations biases the most likely values of inferred stellar parameters and affects the precision with which these parameters can be determined. The importance of these biases depends on the strength of the correlations and the uncertainties. For example, we apply our technique to massive OB stars, but emphasise that it is valid for any type of stars. For effective temperatures and surface gravities determined from atmosphere modelling, we find that masses can be underestimated on average by 0.5σ and mass uncertainties overestimated by a factor of about 2 when neglecting correlations. At the same time, the age precisions are underestimated over a wide range of stellar parameters. We conclude that

  2. Effect of reconstruction methods and x-ray tube current–time product on nodule detection in an anthropomorphic thorax phantom: A crossed-modality JAFROC observer study

    SciTech Connect

    Thompson, J. D., E-mail: j.d.thompson@salford.ac.uk; Chakraborty, D. P.; Szczepura, K.

    Purpose: To evaluate nodule detection in an anthropomorphic chest phantom in computed tomography (CT) images reconstructed with adaptive iterative dose reduction 3D (AIDR{sup 3D}) and filtered back projection (FBP) over a range of tube current–time product (mAs). Methods: Two phantoms were used in this study: (i) an anthropomorphic chest phantom was loaded with spherical simulated nodules of 5, 8, 10, and 12 mm in diameter and +100, −630, and −800 Hounsfield units electron density; this would generate CT images for the observer study; (ii) a whole-body dosimetry verification phantom was used to ultimately estimate effective dose and risk according tomore » the model of the BEIR VII committee. Both phantoms were scanned over a mAs range (10, 20, 30, and 40), while all other acquisition parameters remained constant. Images were reconstructed with both AIDR{sup 3D} and FBP. For the observer study, 34 normal cases (no nodules) and 34 abnormal cases (containing 1–3 nodules, mean 1.35 ± 0.54) were chosen. Eleven observers evaluated images from all mAs and reconstruction methods under the free-response paradigm. A crossed-modality jackknife alternative free-response operating characteristic (JAFROC) analysis method was developed for data analysis, averaging data over the two factors influencing nodule detection in this study: mAs and image reconstruction (AIDR{sup 3D} or FBP). A Bonferroni correction was applied and the threshold for declaring significance was set at 0.025 to maintain the overall probability of Type I error at α = 0.05. Contrast-to-noise (CNR) was also measured for all nodules and evaluated by a linear least squares analysis. Results: For random-reader fixed-case crossed-modality JAFROC analysis, there was no significant difference in nodule detection between AIDR{sup 3D} and FBP when data were averaged over mAs [F(1, 10) = 0.08, p = 0.789]. However, when data were averaged over reconstruction methods, a significant difference was seen between

  3. Analysis of Observational Studies in the Presence of Treatment Selection Bias: Effects of Invasive Cardiac Management on AMI Survival Using Propensity Score and Instrumental Variable Methods

    PubMed Central

    Stukel, Thérèse A.; Fisher, Elliott S; Wennberg, David E.; Alter, David A.; Gottlieb, Daniel J.; Vermeulen, Marian J.

    2007-01-01

    Context Comparisons of outcomes between patients treated and untreated in observational studies may be biased due to differences in patient prognosis between groups, often because of unobserved treatment selection biases. Objective To compare 4 analytic methods for removing the effects of selection bias in observational studies: multivariable model risk adjustment, propensity score risk adjustment, propensity-based matching, and instrumental variable analysis. Design, Setting, and Patients A national cohort of 122 124 patients who were elderly (aged 65–84 years), receiving Medicare, and hospitalized with acute myocardial infarction (AMI) in 1994–1995, and who were eligible for cardiac catheterization. Baseline chart reviews were taken from the Cooperative Cardiovascular Project and linked to Medicare health administrative data to provide a rich set of prognostic variables. Patients were followed up for 7 years through December 31, 2001, to assess the association between long-term survival and cardiac catheterization within 30 days of hospital admission. Main Outcome Measure Risk-adjusted relative mortality rate using each of the analytic methods. Results Patients who received cardiac catheterization (n=73 238) were younger and had lower AMI severity than those who did not. After adjustment for prognostic factors by using standard statistical risk-adjustment methods, cardiac catheterization was associated with a 50% relative decrease in mortality (for multivariable model risk adjustment: adjusted relative risk [RR], 0.51; 95% confidence interval [CI], 0.50–0.52; for propensity score risk adjustment: adjusted RR, 0.54; 95% CI, 0.53–0.55; and for propensity-based matching: adjusted RR, 0.54; 95% CI, 0.52–0.56). Using regional catheterization rate as an instrument, instrumental variable analysis showed a 16% relative decrease in mortality (adjusted RR, 0.84; 95% CI, 0.79–0.90). The survival benefits of routine invasive care from randomized clinical trials

  4. A phantom-based JAFROC observer study of two CT reconstruction methods: the search for optimisation of lesion detection and effective dose

    NASA Astrophysics Data System (ADS)

    Thompson, John D.; Chakraborty, Dev P.; Szczepura, Katy; Vamvakas, Ioannis; Tootell, Andrew; Manning, David J.; Hogg, Peter

    2015-03-01

    Purpose: To investigate the dose saving potential of iterative reconstruction (IR) in a computed tomography (CT) examination of the thorax. Materials and Methods: An anthropomorphic chest phantom containing various configurations of simulated lesions (5, 8, 10 and 12mm; +100, -630 and -800 Hounsfield Units, HU) was imaged on a modern CT system over a tube current range (20, 40, 60 and 80mA). Images were reconstructed with (IR) and filtered back projection (FBP). An ATOM 701D (CIRS, Norfolk, VA) dosimetry phantom was used to measure organ dose. Effective dose was calculated. Eleven observers (15.11+/-8.75 years of experience) completed a free response study, localizing lesions in 544 single CT image slices. A modified jackknife alternative free-response receiver operating characteristic (JAFROC) analysis was completed to look for a significant effect of two factors: reconstruction method and tube current. Alpha was set at 0.05 to control the Type I error in this study. Results: For modified JAFROC analysis of reconstruction method there was no statistically significant difference in lesion detection performance between FBP and IR when figures-of-merit were averaged over tube current (F(1,10)=0.08, p = 0.789). For tube current analysis, significant differences were revealed between multiple pairs of tube current settings (F(3,10) = 16.96, p<0.001) when averaged over image reconstruction method. Conclusion: The free-response study suggests that lesion detection can be optimized at 40mA in this phantom model, a measured effective dose of 0.97mSv. In high-contrast regions the diagnostic value of IR, compared to FBP, is less clear.

  5. Medication safety research by observational study design.

    PubMed

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

    2016-06-01

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

  6. Building Capacity to Use Earth Observations in Decision Making: A Case Study of NASA's DEVELOP National Program Methods and Best Practices

    NASA Astrophysics Data System (ADS)

    Childs-Gleason, L. M.; Ross, K. W.; Crepps, G.; Miller, T. N.; Favors, J. E.; Rogers, L.; Allsbrook, K. N.; Bender, M. R.; Ruiz, M. L.

    2015-12-01

    NASA's DEVELOP National Program fosters an immersive research environment for dual capacity building. Through rapid feasibility Earth science projects, the future workforce and current decision makers are engaged in research projects to build skills and capabilities to use Earth observation in environmental management and policy making. DEVELOP conducts over 80 projects annually, successfully building skills through partnerships with over 150 organizations and providing over 350 opportunities for project participants each year. Filling a void between short-term training courses and long-term research projects, the DEVELOP model has been successful in supporting state, local, federal and international government organizations to adopt methodologies and enhance decision making processes. This presentation will highlight programmatic best practices, feedback from participants and partner organizations, and three sample case studies of successful adoption of methods in the decision making process.

  7. Observational Studies: Cohort and Case-Control Studies

    PubMed Central

    Song, Jae W.; Chung, Kevin C.

    2010-01-01

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

  8. PM2.5 Characterization for Time Series Studies: Organic Molecular Marker Speciation Methods and Observations from Daily Measurements in Denver

    PubMed Central

    Dutton, Steven J.; Williams, Daniel E.; Garcia, Jessica K.; Vedal, Sverre; Hannigan, Michael P.

    2009-01-01

    Particulate matter less than 2.5 microns in diameter (PM2.5) has been shown to have a wide range of adverse health effects and consequently is regulated in accordance with the US-EPA’s National Ambient Air Quality Standards. PM2.5 originates from multiple primary sources and is also formed through secondary processes in the atmosphere. It is plausible that some sources form PM2.5 that is more toxic than PM2.5 from other sources. Identifying the responsible sources could provide insight into the biological mechanisms causing the observed health effects and provide a more efficient approach to regulation. This is the goal of the Denver Aerosol Sources and Health (DASH) study, a multi-year PM2.5 source apportionment and health study. The first step in apportioning the PM2.5 to different sources is to determine the chemical make-up of the PM2.5. This paper presents the methodology used during the DASH study for organic speciation of PM2.5. Specifically, methods are covered for solvent extraction of non-polar and semi-polar organic molecular markers using gas chromatography-mass spectrometry (GC-MS). Vast reductions in detection limits were obtained through the use of a programmable temperature vaporization (PTV) inlet along with other method improvements. Results are presented for the first 1.5 years of the DASH study revealing seasonal and source-related patterns in the molecular markers and their long-term correlation structure. Preliminary analysis suggests that point sources are not a significant contributor to the organic molecular markers measured at our receptor site. Several motor vehicle emission markers help identify a gasoline/diesel split in the ambient data. Findings show both similarities and differences when compared with other cities where similar measurements and assessments have been made. PMID:20161318

  9. The Moment Study: protocol for a mixed method observational cohort study of the Alternative Nicotine Delivery Systems (ANDS) initiation process among adult cigarette smokers.

    PubMed

    Pearson, Jennifer L; Smiley, Sabrina L; Rubin, Leslie F; Anesetti-Rothermel, Andrew; Elmasry, Hoda; Davis, Megan; DeAtley, Teresa; Harvey, Emily; Kirchner, Thomas; Abrams, David B

    2016-04-22

    Alternative Nicotine Delivery Systems (ANDS) such as e-cigarettes are battery-powered devices that aerosolize nicotine and other substances to simulate smoking without using tobacco. Little is known about the ANDS initiation process among adult smokers. The aims of this research are threefold to: (1) examine how ANDS use affects cigarette use; (2) examine how the immediate environmental and psychosocial contexts of cigarette and ANDS use vary within-and between-participants in general and by menthol preference and race; and, (3) examine participants' 'lived experience' of the subjective perceptions, meaning, influences and utility of cigarette and ANDS use. This study's mixed method, 6-week longitudinal design will produce a detailed description of the ANDS initiation process among adult smokers (N=100). Qualitative and quantitative data collection will include 3 weeks of: (1) ecological momentary assessment of patterns of cigarette/ANDS use, satisfaction, mood and craving; (2) geospatial assessment of participants' environment, including indoor and outdoor cigarette/ANDS norms and rules; (3) in-depth interviews about the meaning and utility of cigarette smoking and ANDS use; and, (4) saliva cotinine and exhaled carbon monoxide (CO) biomarkers. A diverse sample will be recruited with an equal number of menthol and non-menthol cigarette smokers. As the primary independent variable, we will investigate how ANDS use affects cigarette consumption. We will also examine how smoking-related and ANDS-related rules and norms surrounding product use influence cigarette and ANDS product use, and how the subjective effects of ANDS use affect ANDS perceptions, beliefs and use. This study was funded by the National Institute on Drug Abuse of the US National Institutes of Health (1R21DA036472), registered at ClinicalTrials.gov (NCT02261363), and approved by the Chesapeake IRB (Pro00008526). Findings will be disseminated to the scientific and lay community through presentations

  10. Evaluation of internal noise methods for Hotelling observers

    NASA Astrophysics Data System (ADS)

    Zhang, Yani; Pham, Binh T.; Eckstein, Miguel P.

    2005-04-01

    Including internal noise in computer model observers to degrade model observer performance to human levels is a common method to allow for quantitatively comparisons of human and model performance. In this paper, we studied two different types of methods for injecting internal noise to Hotelling model observers. The first method adds internal noise to the output of the individual channels: a) Independent non-uniform channel noise, b) Independent uniform channel noise. The second method adds internal noise to the decision variable arising from the combination of channel responses: a) internal noise standard deviation proportional to decision variable's standard deviation due to the external noise, b) internal noise standard deviation proportional to decision variable's variance caused by the external noise. We tested the square window Hotelling observer (HO), channelized Hotelling observer (CHO), and Laguerre-Gauss Hotelling observer (LGHO). The studied task was detection of a filling defect of varying size/shape in one of four simulated arterial segment locations with real x-ray angiography backgrounds. Results show that the internal noise method that leads to the best prediction of human performance differs across the studied models observers. The CHO model best predicts human observer performance with the channel internal noise. The HO and LGHO best predict human observer performance with the decision variable internal noise. These results might help explain why previous studies have found different results on the ability of each Hotelling model to predict human performance. Finally, the present results might guide researchers with the choice of method to include internal noise into their Hotelling models.

  11. 'Before reaching the last mile'- Knowledge, attitude, practice and perceived barriers related to tuberculosis directly observed therapy among ASHA workers in Central India: A mixed method study.

    PubMed

    Singh, Akash Ranjan; Pakhare, Abhijit; Kokane, Arun M; Shewade, Hemant Deepak; Chauhan, Ashish; Singh, Abhishek; Gangwar, Arti; Thakur, Prahlad Singh

    2017-12-01

    Community-based direct observed treatment (DOT) providers are an important bridge for the national tuberculosis programme in India to reach the unreached. The present study has explored the knowledge, attitude, practice and barriers perceived by the community-based DOT providers. Mixed-methods study design was used among 41 community-based DOT providers (Accredited Social Health Activist (ASHAs)) working in 67 villages from a primary health center in Raisen district of Madhya Pradesh, India. The cross-sectional quantitative component assessed the knowledge and practices and three focus-group discussions explored the attitude and perceived barriers related to DOT provision. 'Adequate knowledge' and 'satisfactory practice' related to DOT provision was seen in 14 (34%) and 13 (32%) ASHAs respectively. Only two (5%) received any amount of honorarium for completion of DOT in last 3years. The focus-group discussions revealed unfavourable attitude; inadequate training and supervision, non-payment of honorarium, issues related to assured services after referral and patient related factors as the barriers to satisfactory practice of DOT. Study revealed inadequate knowledge and unsatisfactory practice related to DOT provision among ASHAs. Innovations addressing the perceived barriers to improve practice of DOT provision by ASHAs are urgently required. Copyright © 2017 Ministry of Health, Saudi Arabia. Published by Elsevier Ltd. All rights reserved.

  12. Distracted Biking: An Observational Study.

    PubMed

    Wolfe, Elizabeth Suzanne; Arabian, Sandra Strack; Breeze, Janis L; Salzler, Matthew J

    2016-01-01

    Commuting via bicycle is a very popular mode of transportation in the Northeastern United States. Boston, MA, has seen a rapid increase in bicycle ridership over the past decade, which has raised concerns and awareness about bicycle safety. An emerging topic in this field is distracted bicycle riding. This study was conducted to provide descriptive data on the prevalence and type of distracted bicycling in Boston at different times of day. This was a cross-sectional study in which observers tallied bicyclists at 4 high traffic intersections in Boston during various peak commuting hours for 2 types of distractions: auditory (earbuds/phones in or on ears), and visual/tactile (electronic device or other object in hand). Nineteen hundred seventy-four bicyclists were observed and 615 (31.2%), 95% CI [29, 33%], were distracted. Of those observed, auditory distractions were the most common (N = 349; 17.7%), 95% CI [16, 19], p = .0003, followed by visual/tactile distractions (N = 266; 13.5%), 95% CI [12, 15]. The highest proportion (40.7%), 95% CI [35, 46], of distracted bicyclists was observed during the midday commute (between 13:30 and 15:00). Distracted bicycling is a prevalent safety concern in the city of Boston, as almost a third of all bicyclists exhibited distracted behavior. Education and public awareness campaigns should be designed to decrease distracted bicycling behaviors and promote bicycle safety in Boston. An awareness of the prevalence of distracted biking can be utilized to promote bicycle safety campaigns dedicated to decreasing distracted bicycling and to provide a baseline against which improvements can be measured.

  13. Distracted Biking: An Observational Study

    PubMed Central

    Wolfe, Elizabeth Suzanne; Arabian, Sandra Strack; Breeze, Janis L; Salzler, Matthew J.

    2016-01-01

    Commuting via bicycle is a very popular mode of transportation in the Northeastern United States (US). Boston, MA has seen a rapid increase in bicycle ridership over the past decade which has raised concerns and awareness about bicycle safety. An emerging topic in this field is distracted bicycle riding. This study was conducted to provide descriptive data on the prevalence and type of distracted bicycling in Boston at different times of day. This was a cross-sectional study in which observers tallied bicyclists at four high traffic intersections in Boston during various peak commuting hours for two types of distractions: auditory (ear buds/phones in or on ears), and visual/tactile (electronic device or other object in hand). Nineteen hundred seventy-four bicyclists were observed and 615 (31.2%, 95% CI: 29%-33%) were distracted. Of those observed, auditory distractions were the most common (N= 349 [17.7%, 95% CI: 16%-19%], p=0.0003) followed by visual/tactile distractions (N= 266 [13.5%, 95% CI: 12%-15%]). The highest proportion (40.7%, 95% CI: 35%-46%) of distracted bicyclists was observed during the midday commute (between 13:30-15:00). Distracted bicycling is a prevalent safety concern in the city of Boston, as almost one-third of all bicyclists exhibited distracted behavior. Education and public awareness campaigns should be designed to decrease distracted bicycling behaviors and promote bicycle safety in Boston. An awareness of the prevalence of distracted biking can be utilized to promote bicycle safety campaigns dedicated to decreasing distracted bicycling and to provide a baseline against which improvements can be measured. PMID:26953533

  14. Ways of learning: Observational studies versus experiments

    USGS Publications Warehouse

    Shaffer, T.L.; Johnson, D.H.

    2008-01-01

    Manipulative experimentation that features random assignment of treatments, replication, and controls is an effective way to determine causal relationships. Wildlife ecologists, however, often must take a more passive approach to investigating causality. Their observational studies lack one or more of the 3 cornerstones of experimentation: controls, randomization, and replication. Although an observational study can be analyzed similarly to an experiment, one is less certain that the presumed treatment actually caused the observed response. Because the investigator does not actively manipulate the system, the chance that something other than the treatment caused the observed results is increased. We reviewed observational studies and contrasted them with experiments and, to a lesser extent, sample surveys. We identified features that distinguish each method of learning and illustrate or discuss some complications that may arise when analyzing results of observational studies. Findings from observational studies are prone to bias. Investigators can reduce the chance of reaching erroneous conclusions by formulating a priori hypotheses that can be pursued multiple ways and by evaluating the sensitivity of study conclusions to biases of various magnitudes. In the end, however, professional judgment that considers all available evidence is necessary to render a decision regarding causality based on observational studies.

  15. Determination of the best method to estimate glomerular filtration rate from serum creatinine in adult patients with sickle cell disease: a prospective observational cohort study.

    PubMed

    Arlet, Jean-Benoît; Ribeil, Jean-Antoine; Chatellier, Gilles; Eladari, Dominique; De Seigneux, Sophie; Souberbielle, Jean-Claude; Friedlander, Gérard; de Montalembert, Marianne; Pouchot, Jacques; Prié, Dominique; Courbebaisse, Marie

    2012-08-06

    Sickle cell disease (SCD) leads to tissue hypoxia resulting in chronic organ dysfunction including SCD associated nephropathy. The goal of our study was to determine the best equation to estimate glomerular filtration rate (GFR) in SCD adult patients. We conducted a prospective observational cohort study. Since 2007, all adult SCD patients in steady state, followed in two medical departments, have had their GFR measured using iohexol plasma clearance (gold standard). The Cockcroft-Gault, MDRD-v4, CKP-EPI and finally, MDRD and CKD-EPI equations without adjustment for ethnicity were tested to estimate GFR from serum creatinine. Estimated GFRs were compared to measured GFRs according to the graphical Bland and Altman method. Sixty-four SCD patients (16 men, median age 27.5 years [range 18.0-67.5], 41 with SS-genotype were studied. They were Sub-Saharan Africa and French West Indies natives and predominantly lean (median body mass index: 22 kg/m2 [16-33]). Hyperfiltration (defined as measured GFR >110 mL/min/1.73 m2) was detected in 53.1% of patients. Urinary albumin/creatinine ratio was higher in patients with hyperfiltration than in patients with normal GFR (4.05 mg/mmol [0.14-60] versus 0.4 mg/mmol [0.7-81], p = 0.01). The CKD-EPI equation without adjustment for ethnicity had both the lowest bias and the greatest precision. Differences between estimated GFRs using the CKP-EPI equation and measured GFRs decreased with increasing GFR values, whereas it increased with the Cockcroft-Gault and MDRD-v4 equations. We confirm that SCD patients have a high rate of glomerular hyperfiltration, which is frequently associated with microalbuminuria or macroalbuminuria. In non-Afro-American SCD patients, the best method for estimating GFR from serum creatinine is the CKD-EPI equation without adjustment for ethnicity. This equation is particularly accurate to estimate high GFR values, including glomerular hyperfiltration, and thus should be recommended to screen SCD adult patients

  16. Milk Options Observation (MOO): A Mixed-Methods Study of Chocolate Milk Removal on Beverage Consumption and Student/Staff Behaviors in a Rural Elementary School

    ERIC Educational Resources Information Center

    Davis, Melinda M.; Spurlock, Margaret; Ramsey, Katrina; Smith, Jamie; Beamer, Beth Ann; Aromaa, Susan; McGinnis, Paul B.

    2017-01-01

    Providing flavored milk in school lunches is controversial, with conflicting evidence on its impact on nutritional intake versus added sugar consumption and excess weight gain. Nonindustry-sponsored studies using individual-level analyses are needed. Therefore, we conducted this mixed-methods study of flavored milk removal at a rural primary…

  17. Study of swelling behavior in ArF resist during development by the QCM method (3): observations of swelling layer elastic modulus

    NASA Astrophysics Data System (ADS)

    Sekiguchi, Atsushi

    2013-03-01

    The QCM method allows measurements of impedance, an index of swelling layer viscosity in a photoresist during development. While impedance is sometimes used as a qualitative index of change in the viscosity of the swelling layer, it has to date not been used quantitatively, for data analysis. We explored a method for converting impedance values to elastic modulus (Pa), a coefficient expressing viscosity. Applying this method, we compared changes in the viscosity of the swelling layer in an ArF resist generated during development in a TMAH developing solution and in a TBAH developing solution. This paper reports the results of this comparative study.

  18. The Alberta smoke plume observation study

    NASA Astrophysics Data System (ADS)

    Anderson, Kerry; Pankratz, Al; Mooney, Curtis; Fleetham, Kelly

    2018-02-01

    A field project was conducted to observe and measure smoke plumes from wildland fires in Alberta. This study used handheld inclinometer measurements and photos taken at lookout towers in the province. Observations of 222 plumes were collected from 21 lookout towers over a 6-year period from 2010 to 2015. Observers reported the equilibrium and maximum plume heights based on the plumes' final levelling heights and the maximum lofting heights, respectively. Observations were tabulated at the end of each year and matched to reported fires. Fire sizes at assessment times and forest fuel types were reported by the province. Fire weather conditions were obtained from the Canadian Wildland Fire Information System (CWFIS). Assessed fire sizes were adjusted to the appropriate size at plume observation time using elliptical fire-growth projections. Though a logical method to collect plume observations in principle, many unanticipated issues were uncovered as the project developed. Instrument limitations and environmental conditions presented challenges to the investigators, whereas human error and the subjectivity of observations affected data quality. Despite these problems, the data set showed that responses to fire behaviour conditions were consistent with the physical processes leading to plume rise. The Alberta smoke plume observation study data can be found on the Canadian Wildland Fire Information System datamart (Natural Resources Canada, 2018) at http://cwfis.cfs.nrcan.gc.ca/datamart.

  19. Errors Using Observational Methods for Ergonomics Assessment in Real Practice.

    PubMed

    Diego-Mas, Jose-Antonio; Alcaide-Marzal, Jorge; Poveda-Bautista, Rocio

    2017-12-01

    The degree in which practitioners use the observational methods for musculoskeletal disorder risks assessment correctly was evaluated. Ergonomics assessment is a key issue for the prevention and reduction of work-related musculoskeletal disorders in workplaces. Observational assessment methods appear to be better matched to the needs of practitioners than direct measurement methods, and for this reason, they are the most widely used techniques in real work situations. Despite the simplicity of observational methods, those responsible for assessing risks using these techniques should have some experience and know-how in order to be able to use them correctly. We analyzed 442 risk assessments of actual jobs carried out by 290 professionals from 20 countries to determine their reliability. The results show that approximately 30% of the assessments performed by practitioners had errors. In 13% of the assessments, the errors were severe and completely invalidated the results of the evaluation. Despite the simplicity of observational method, approximately 1 out of 3 assessments conducted by practitioners in actual work situations do not adequately evaluate the level of potential musculoskeletal disorder risks. This study reveals a problem that suggests greater effort is needed to ensure that practitioners possess better knowledge of the techniques used to assess work-related musculoskeletal disorder risks and that laws and regulations should be stricter as regards qualifications and skills required by professionals.

  20. [Comparison of surface light scattering of acrylic intraocular lenses made by lathe-cutting and cast-molding methods--long-term observation and experimental study].

    PubMed

    Nishihara, Hitoshi; Ayaki, Masahiko; Watanabe, Tomiko; Ohnishi, Takeo; Kageyama, Toshiyuki; Yaguchi, Shigeo

    2004-03-01

    To compare the long-term clinical and experimental results of soft acrylic intraocular lenses(IOLs) manufactured by the lathe-cut(LC) method and by the cast-molding(CM) method. This was a retrospective study of 20 patients(22 eyes) who were examined in a 5- and 7-year follow-up study. Sixteen eyes were implanted with polyacrylic IOLs manufactured by the LC method and 6 eyes were implanted with polyacrylic IOLs manufactured by the CM method. Postoperative measurements included best corrected visual acuity, contrast sensitivity, biomicroscopic examination, and Scheimpflug slit-lamp images to evaluate surface light scattering. Scanning electron microscopy and three-dimensional surface analysis were conducted. At 7 years, the mean visual acuity was 1.08 +/- 0.24 (mean +/- standard deviation) in the LC group and 1.22 +/- 0.27 in the CM group. Surface light-seatter was 12.0 +/- 4.0 computer compatible tapes(CCT) in the LC group and 37.4 +/- 5.4 CCT in the CM group. Mean surface roughness was 0.70 +/- 0.07 nm in the LC group and 6.16 +/- 0.97 nm in the CM group. Acrylic IOLs manufactured by the LC method are more stable in long-termuse.

  1. Observational methods for solar origin diagnostics of energetic protons

    NASA Astrophysics Data System (ADS)

    Miteva, Rositsa

    2017-12-01

    The aim of the present report is to outline the observational methods used to determine the solar origin - in terms of flares and coronal mass ejections (CMEs) - of the in situ observed solar energetic protons. Several widely used guidelines are given and different sources of uncertainties are summarized and discussed. In the present study, a new quality factor is proposed as a certainty check on the so-identified flare-CME pairs. In addition, the correlations between the proton peak intensity and the properties of their solar origin are evaluated as a function of the quality factor.

  2. Methods for using clinical laboratory test results as baseline confounders in multi-site observational database studies when missing data are expected.

    PubMed

    Raebel, Marsha A; Shetterly, Susan; Lu, Christine Y; Flory, James; Gagne, Joshua J; Harrell, Frank E; Haynes, Kevin; Herrinton, Lisa J; Patorno, Elisabetta; Popovic, Jennifer; Selvan, Mano; Shoaibi, Azadeh; Wang, Xingmei; Roy, Jason

    2016-07-01

    Our purpose was to quantify missing baseline laboratory results, assess predictors of missingness, and examine performance of missing data methods. Using the Mini-Sentinel Distributed Database from three sites, we selected three exposure-outcome scenarios with laboratory results as baseline confounders. We compared hazard ratios (HRs) or risk differences (RDs) and 95% confidence intervals (CIs) from models that omitted laboratory results, included only available results (complete cases), and included results after applying missing data methods (multiple imputation [MI] regression, MI predictive mean matching [PMM] indicator). Scenario 1 considered glucose among second-generation antipsychotic users and diabetes. Across sites, glucose was available for 27.7-58.9%. Results differed between complete case and missing data models (e.g., olanzapine: HR 0.92 [CI 0.73, 1.12] vs 1.02 [0.90, 1.16]). Across-site models employing different MI approaches provided similar HR and CI; site-specific models provided differing estimates. Scenario 2 evaluated creatinine among individuals starting high versus low dose lisinopril and hyperkalemia. Creatinine availability: 44.5-79.0%. Results differed between complete case and missing data models (e.g., HR 0.84 [CI 0.77, 0.92] vs. 0.88 [0.83, 0.94]). HR and CI were identical across MI methods. Scenario 3 examined international normalized ratio (INR) among warfarin users starting interacting versus noninteracting antimicrobials and bleeding. INR availability: 20.0-92.9%. Results differed between ignoring INR versus including INR using missing data methods (e.g., RD 0.05 [CI -0.03, 0.13] vs 0.09 [0.00, 0.18]). Indicator and PMM methods gave similar estimates. Multi-site studies must consider site variability in missing data. Different missing data methods performed similarly. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  3. What are the physical and psychological health effects of suicide bereavement on family members? Protocol for an observational and interview mixed-methods study in Ireland

    PubMed Central

    Larkin, Celine; Corcoran, Paul; Matvienko-Sikar, Karen; Arensman, Ella

    2017-01-01

    Introduction Research indicates that experiencing the suicide of a relative can have a significant impact on family members' emotional health. However, research incorporating the impact of suicide bereavement on family members' physical health is sparse. This paper details the protocol for a mixed-methods study of suicide-bereaved family members. The study will primarily examine the physical and mental health needs of those bereaved by suicide. A secondary objective of the study is to describe the support service needs of family members bereaved by suicide. Methods and analysis A mixed-methods approach, using semistructured interviews and self-report questionnaires, will be used. Interviews will be conducted with a group of 15–20 relatives who experienced suicide bereavement. This protocol will follow the COREQ checklist criteria for the reporting of qualitative research interviews. Thematic analysis will be used to examine experiences and impact of bereavement on psychological and physical health. Self-report quantitative data on well-being will be analysed using descriptive statistics. Ethics and dissemination Ethical approval to conduct this study has been granted from the Clinical Research Ethics Committee of the Cork Teaching Hospitals. Pseudonyms will be given to participants to protect anonymity. It will be explained to participants that participation in the study is voluntary and they have to right to withdraw at any time. The findings of this research will be disseminated to regional, national and international audiences through publication in peer-reviewed international journals and presentations at scientific conferences. This research also forms part of a PhD thesis. PMID:28363930

  4. Parent-Collected Behavioral Observations: An Empirical Comparison of Methods

    ERIC Educational Resources Information Center

    Nadler, Cy B.; Roberts, Mark W.

    2013-01-01

    Treatments for disruptive behaviors are often guided by parent reports on questionnaires, rather than by multiple methods of assessment. Professional observations and clinic analogs exist to complement questionnaires, but parents can also collect useful behavioral observations to inform and guide treatment. Two parent observation methods of child…

  5. A pragmatic method for electronic medical record-based observational studies: developing an electronic medical records retrieval system for clinical research

    PubMed Central

    Yamamoto, Keiichi; Sumi, Eriko; Yamazaki, Toru; Asai, Keita; Yamori, Masashi; Teramukai, Satoshi; Bessho, Kazuhisa; Yokode, Masayuki; Fukushima, Masanori

    2012-01-01

    Objective The use of electronic medical record (EMR) data is necessary to improve clinical research efficiency. However, it is not easy to identify patients who meet research eligibility criteria and collect the necessary information from EMRs because the data collection process must integrate various techniques, including the development of a data warehouse and translation of eligibility criteria into computable criteria. This research aimed to demonstrate an electronic medical records retrieval system (ERS) and an example of a hospital-based cohort study that identified both patients and exposure with an ERS. We also evaluated the feasibility and usefulness of the method. Design The system was developed and evaluated. Participants In total, 800 000 cases of clinical information stored in EMRs at our hospital were used. Primary and secondary outcome measures The feasibility and usefulness of the ERS, the method to convert text from eligible criteria to computable criteria, and a confirmation method to increase research data accuracy. Results To comprehensively and efficiently collect information from patients participating in clinical research, we developed an ERS. To create the ERS database, we designed a multidimensional data model optimised for patient identification. We also devised practical methods to translate narrative eligibility criteria into computable parameters. We applied the system to an actual hospital-based cohort study performed at our hospital and converted the test results into computable criteria. Based on this information, we identified eligible patients and extracted data necessary for confirmation by our investigators and for statistical analyses with our ERS. Conclusions We propose a pragmatic methodology to identify patients from EMRs who meet clinical research eligibility criteria. Our ERS allowed for the efficient collection of information on the eligibility of a given patient, reduced the labour required from the investigators and

  6. What are the physical and psychological health effects of suicide bereavement on family members? Protocol for an observational and interview mixed-methods study in Ireland.

    PubMed

    Spillane, Ailbhe; Larkin, Celine; Corcoran, Paul; Matvienko-Sikar, Karen; Arensman, Ella

    2017-03-30

    Research indicates that experiencing the suicide of a relative can have a significant impact on family members' emotional health. However, research incorporating the impact of suicide bereavement on family members' physical health is sparse. This paper details the protocol for a mixed-methods study of suicide-bereaved family members. The study will primarily examine the physical and mental health needs of those bereaved by suicide. A secondary objective of the study is to describe the support service needs of family members bereaved by suicide. A mixed-methods approach, using semistructured interviews and self-report questionnaires, will be used. Interviews will be conducted with a group of 15-20 relatives who experienced suicide bereavement. This protocol will follow the COREQ checklist criteria for the reporting of qualitative research interviews. Thematic analysis will be used to examine experiences and impact of bereavement on psychological and physical health. Self-report quantitative data on well-being will be analysed using descriptive statistics. Ethical approval to conduct this study has been granted from the Clinical Research Ethics Committee of the Cork Teaching Hospitals. Pseudonyms will be given to participants to protect anonymity. It will be explained to participants that participation in the study is voluntary and they have to right to withdraw at any time. The findings of this research will be disseminated to regional, national and international audiences through publication in peer-reviewed international journals and presentations at scientific conferences. This research also forms part of a PhD thesis. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  7. Reflection on observation: A qualitative study using practice development methods to explore the experience of being a hand hygiene auditor in Australia.

    PubMed

    Jain, Susan; Edgar, Denise; Bothe, Janine; Newman, Helen; Wilson, Annmaree; Bint, Beth; Brown, Megan; Alexander, Suzanne; Harris, Joanna

    2015-12-01

    Within the Australian public health care system, an observation model is used to assess hand hygiene practice in health care workers, culminating in a publicly available healthcare service performance indicator. The intent of this study was for the results to inform the development of a strategy to support individual auditors and local sustainability of the hand hygiene auditing program. This qualitative study used a values clarification tool to gain an understanding of the experiences of hand hygiene auditors. The methodology involved qualitative interpretation of focus group discussions to identify the enablers and barriers to successful performance of the auditors' role. Twenty-five participants identified congruous themes of the need for peer and managerial support, improved communication and feedback, and consideration for succession planning. There was consistency in the participants' most frequently identified significant barriers in undertaking the role. Hand hygiene auditors take pride in their role and work toward the goal of reducing health care-associated infections by having a part to play in improving hand hygiene practices of all staff members. Important themes, barriers, and enablers were identified in this study. This research will be of interest nationally and globally, considering the dearth of published information on the experience of hand hygiene auditors. This study provides evidence of the need to support individual hand hygiene auditors. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

  8. Computerised lung sound analysis to improve the specificity of paediatric pneumonia diagnosis in resource-poor settings: protocol and methods for an observational study

    PubMed Central

    Gilman, Robert H; Tielsch, James M; Steinhoff, Mark; Figueroa, Dante; Rodriguez, Shalim; Caffo, Brian; Tracey, Brian; Elhilali, Mounya; West, James; Checkley, William

    2012-01-01

    Introduction WHO case management algorithm for paediatric pneumonia relies solely on symptoms of shortness of breath or cough and tachypnoea for treatment and has poor diagnostic specificity, tends to increase antibiotic resistance. Alternatives, including oxygen saturation measurement, chest ultrasound and chest auscultation, exist but with potential disadvantages. Electronic auscultation has potential for improved detection of paediatric pneumonia but has yet to be standardised. The authors aim to investigate the use of electronic auscultation to improve the specificity of the current WHO algorithm in developing countries. Methods This study is designed to test the hypothesis that pulmonary pathology can be differentiated from normal using computerised lung sound analysis (CLSA). The authors will record lung sounds from 600 children aged ≤5 years, 100 each with consolidative pneumonia, diffuse interstitial pneumonia, asthma, bronchiolitis, upper respiratory infections and normal lungs at a children's hospital in Lima, Peru. The authors will compare CLSA with the WHO algorithm and other detection approaches, including physical exam findings, chest ultrasound and microbiologic testing to construct an improved algorithm for pneumonia diagnosis. Discussion This study will develop standardised methods for electronic auscultation and chest ultrasound and compare their utility for detection of pneumonia to standard approaches. Utilising signal processing techniques, the authors aim to characterise lung sounds and through machine learning, develop a classification system to distinguish pathologic sounds. Data will allow a better understanding of the benefits and limitations of novel diagnostic techniques in paediatric pneumonia. PMID:22307098

  9. Towards an improved global understanding of treatment and outcomes in people with type 2 diabetes: Rationale and methods of the DISCOVER observational study program.

    PubMed

    Ji, Linong; Bonnet, Fabrice; Charbonnel, Bernard; Gomes, Marilia B; Kosiborod, Mikhail; Khunti, Kamlesh; Nicolucci, Antonio; Pocock, Stuart; Rathmann, Wolfgang; Shestakova, Marina V; Shimomura, Iichiro; Watada, Hirotaka; Fenici, Peter; Hammar, Niklas; Hashigami, Kiyoshi; Macaraeg, Greg; Surmont, Filip; Medina, Jesús

    2017-07-01

    Contemporary global real-world data on the management of type 2 diabetes are scarce. The global DISCOVER study program aims to describe the disease management patterns and a broad range of associated outcomes in patients with type 2 diabetes initiating a second-line glucose-lowering therapy in routine clinical practice. The DISCOVER program comprises two longitudinal observational studies involving more than 15,000 patients in 38 countries across six continents. Study sites have been selected to be representative of type 2 diabetes management in each country. Data will be collected at baseline (initiation of second-line therapy), at 6months, and yearly during a 3-year follow-up period. The DISCOVER program will record patient, healthcare provider, and healthcare system characteristics, treatment patterns, and factors influencing changes in therapy. In addition, disease control (e.g. achievement of glycated hemoglobin target), management of associated risk factors (e.g. hypercholesterolemia and hypertension), and healthcare resource utilization will be recorded. Microvascular and macrovascular complications, incidence of hypoglycemic events, and patient-reported outcomes will also be captured. The DISCOVER program will provide insights into the current management of patients with type 2 diabetes worldwide, which will contribute to informing future clinical guidelines and improving patient care. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  10. What are the physical and psychological health effects of suicide bereavement on family members? An observational and interview mixed-methods study in Ireland

    PubMed Central

    Matvienko-Sikar, Karen; Larkin, Celine; Corcoran, Paul; Arensman, Ella

    2018-01-01

    Objectives Research focussing on the impact of suicide bereavement on family members’ physical and psychological health is scarce. The aim of this study was to examine how family members have been physically and psychologically affected following suicide bereavement. A secondary objective of the study was to describe the needs of family members bereaved by suicide. Design A mixed-methods study was conducted, using qualitative semistructured interviews and additional quantitative self-report measures of depression, anxiety and stress (DASS-21). Setting Consecutive suicide cases and next-of-kin were identified by examining coroner’s records in Cork City and County, Ireland from October 2014 to May 2016. Participants Eighteen family members bereaved by suicide took part in a qualitative interview. They were recruited from the Suicide Support and Information System: A Case-Control Study (SSIS-ACE), where family members bereaved by suicide (n=33) completed structured measures of their well-being. Results Qualitative findings indicated three superordinate themes in relation to experiences following suicide bereavement: (1) co-occurrence of grief and health reactions; (2) disparity in supports after suicide and (3) reconstructing life after deceased’s suicide. Initial feelings of guilt, blame, shame and anger often manifested in enduring physical, psychological and psychosomatic difficulties. Support needs were diverse and were often related to the availability or absence of informal support by family or friends. Quantitative results indicated that the proportion of respondents above the DASS-21 cut-offs respectively were 24% for depression, 18% for anxiety and 27% for stress. Conclusions Healthcare professionals’ awareness of the adverse physical and psychosomatic health difficulties experienced by family members bereaved by suicide is essential. Proactively facilitating support for this group could help to reduce the negative health sequelae. The effects of

  11. Offering fragile X syndrome carrier screening: a prospective mixed-methods observational study comparing carrier screening of pregnant and non-pregnant women in the general population

    PubMed Central

    Martyn, M; Anderson, V; Archibald, A; Carter, R; Cohen, J; Delatycki, M; Donath, S; Emery, J; Halliday, J; Hill, M; Sheffield, L; Slater, H; Tassone, F; Younie, S; Metcalfe, S

    2013-01-01

    Introduction Fragile X syndrome (FXS) is the leading cause of inherited intellectual and developmental disability. Policy development relating to carrier screening programmes for FXS requires input from large studies examining not only test uptake but also psychosocial aspects. This study will compare carrier screening in pregnant and non-pregnant populations, examining informed decision-making, psychosocial issues and health economics. Methods and Analysis Pregnant and non-pregnant women are being recruited from general practices and obstetric services. Women receive study information either in person or through clinic mail outs. Women are provided pretest counselling by a genetic counsellor and make a decision about testing in their own time. Data are being collected from two questionnaires: one completed at the time of making the decision about testing and the second 1 month later. Additional data are gathered through qualitative interviews conducted at several time points with a subset of participating women, including all women with a positive test result, and with staff from recruiting clinics. A minimum sample size of 500 women/group has been calculated to give us 88% power to detect a 10% difference in test uptake and 87% power to detect a 10% difference in informed choice between the pregnant and non-pregnant groups. Questionnaire data will be analysed using descriptive statistics and multivariate logistic regression models. Interview data will be thematically analysed. Willingness-to-pay and cost effectiveness analyses will also be performed. Recruitment started in July 2009 and data collection will be completed by December 2013. Ethics and Dissemination Ethics approval has been granted by the Universities of Melbourne and Western Australia and by recruiting clinics, where required. Results will be reported in peer-reviewed publications, conference presentations and through a website http://www.fragilexscreening.net.au. The results of this study will

  12. Data-centric method for object observation through scattering media

    NASA Astrophysics Data System (ADS)

    Tanida, Jun; Horisaki, Ryoichi

    2018-03-01

    A data-centric method is introduced for object observation through scattering media. A large number of training pairs are used to characterize the relation between the object and the observation signals based on machine learning. Using the method object information can be retrieved even from strongly-disturbed signals. As potential applications, object recognition, imaging, and focusing through scattering media were demonstrated.

  13. The Congolobe project, a multidisciplinary study of Congo deep-sea fan lobe complex: Overview of methods, strategies, observations and sampling

    NASA Astrophysics Data System (ADS)

    Rabouille, C.; Olu, K.; Baudin, F.; Khripounoff, A.; Dennielou, B.; Arnaud-Haond, S.; Babonneau, N.; Bayle, C.; Beckler, J.; Bessette, S.; Bombled, B.; Bourgeois, S.; Brandily, C.; Caprais, J. C.; Cathalot, C.; Charlier, K.; Corvaisier, R.; Croguennec, C.; Cruaud, P.; Decker, C.; Droz, L.; Gayet, N.; Godfroy, A.; Hourdez, S.; Le Bruchec, J.; Saout, J.; Le Saout, M.; Lesongeur, F.; Martinez, P.; Mejanelle, L.; Michalopoulos, P.; Mouchel, O.; Noel, P.; Pastor, L.; Picot, M.; Pignet, P.; Pozzato, L.; Pruski, A. M.; Rabiller, M.; Raimonet, M.; Ragueneau, O.; Reyss, J. L.; Rodier, P.; Ruesch, B.; Ruffine, L.; Savignac, F.; Senyarich, C.; Schnyder, J.; Sen, A.; Stetten, E.; Sun, Ming Yi; Taillefert, M.; Teixeira, S.; Tisnerat-Laborde, N.; Toffin, L.; Tourolle, J.; Toussaint, F.; Vétion, G.; Jouanneau, J. M.; Bez, M.; Congolobe Group:

    2017-08-01

    The presently active region of the Congo deep-sea fan (around 330,000 km2), called the terminal lobes or lobe complex, covers an area of 2500 km2 at 4700-5100 m water depth and 750-800 km offshore. It is a unique sedimentary area in the world ocean fed by a submarine canyon and a channel-levee system which presently deliver large amounts of organic carbon originating from the Congo River by turbidity currents. This particularity is due to the deep incision of the shelf by the Congo canyon, up to 30 km into the estuary, which funnels the Congo River sediments into the deep-sea. The connection between the river and the canyon is unique for major world rivers. In 2011, two cruises (WACS leg 2 and Congolobe) were conducted to simultaneously investigate the geology, organic and inorganic geochemistry, and micro- and macro-biology of the terminal lobes of the Congo deep-sea fan. Using this multidisciplinary approach, the morpho-sedimentary features of the lobes were characterized along with the origin and reactivity of organic matter, the recycling and burial of biogenic compounds, the diversity and function of bacterial and archaeal communities within the sediment, and the biodiversity and functioning of the faunal assemblages on the seafloor. Six different sites were selected for this study: Four distributed along the active channel from the lobe complex entrance to the outer rim of the sediment deposition zone, and two positioned cross-axis and at increasing distance from the active channel, thus providing a gradient in turbidite particle delivery and sediment age. This paper aims to provide the general context of this multidisciplinary study. It describes the general features of the site and the overall sampling strategy and provides the initial habitat observations to guide the other in-depth investigations presented in this special issue. Detailed bathymetry of each sampling site using 0.1-1 m resolution multibeam obtained with a remotely operated vehicle (ROV

  14. Methods on observation of fluorescence micro-imaging for microalgae

    NASA Astrophysics Data System (ADS)

    Ou, Lin; Zhuang, Hui-ru; Chen, Rong; Lei, Jin-pin; Liao, Xiao-hua; Lin, Wen-suo

    2007-11-01

    Objective: Auto-fluorescence micro-imaging of microalgae are observed by using of laser scanning confocal microscopy (LSCM) and fluorescence microscopy, so as to investigate the effect of auto fluorescence alteration on growth of irradiated microalgae irradiated, meanwhile, the method of microalgae cells stained also to be studied. Methods: Platymonas subcordiformis, Phaeodactylum tricormutum and Isochyrsis zhanjiangensis cells are stained with acridine orange, and observed by fluorescence microscopy; the three types microalgae mentioned above are irradiated by Nd:YAP laser with 10w at 1341nm, irradiating time:12s, 30s, 35s and 55s, than to be cultured 6 days, and the auto fluorescence images and fluorescence spectra of algae cells are obtained by LSCM on lambda scan mode, at excitation 488nm (Ar + laser). Results: It is showed that the shapes and the structural features of microalgae cells stained can be seen clearly, and the cytoplasm and nucleus also can be observed. The chloroplasts in cell is bigger on promoting effects, conversely, it is to be mutilated, deformation and shrink. Contrast to the CK, the peak positions of fluorescence of algae cells irradiated is similar to the whole while the peak light intensity alters. On irradiation of promoting dose, however, the auto fluorescence intensity is enhanced more than control. Conclusions: The method of cell stained can be used to observed genetic material in microalgae. There are obvious effects for laser irradiating to chloroplasts in cells, the bigger chloroplasts the greater fluorescence intensity. Physiological incentive effects of microalgae irradiated can be given expression on fluorescence characteristics and fluorescence intensity alteration of cells.

  15. What is the impact of an electronic test result acknowledgement system on Emergency Department physicians' work processes? A mixed-method pre-post observational study.

    PubMed

    Georgiou, Andrew; McCaughey, Euan J; Tariq, Amina; Walter, Scott R; Li, Julie; Callen, Joanne; Paoloni, Richard; Runciman, William B; Westbrook, Johanna I

    2017-03-01

    To examine the impact of an electronic Results Acknowledgement (eRA) system on emergency physicians' test result management work processes and the time taken to acknowledge microbiology and radiology test results for patients discharged from an Emergency Department (ED). The impact of the eRA system was assessed in an Australian ED using: a) semi-structured interviews with senior emergency physicians; and b) a time and motion direct observational study of senior emergency physicians completing test acknowledgment pre and post the implementation of the eRA system. The eRA system led to changes in the way results and actions were collated, stored, documented and communicated. Although there was a non-significant increase in the average time taken to acknowledge results in the post period, most types of acknowledgements (other than simple acknowledgements) took less time to complete. The number of acknowledgements where physicians sought additional information from the Electronic Medical Record (EMR) rose from 12% pre to 20% post implementation of eRA. Given that the type of results are unlikely to have changed significantly across the pre and post implementation periods, the increase in the time physicians spent accessing additional clinical information in the post period likely reflects the greater access to clinical information provided by the integrated electronic system. Easier access to clinical information may improve clinical decision making and enhance the quality of patient care. For instance, in situations where a senior clinician, not initially involved in the care process, is required to deal with the follow-up of non-normal results. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. Methods of Studying Persons.

    ERIC Educational Resources Information Center

    Heinemann, Allen W.; Shontz, Franklin C.

    1985-01-01

    Describes a method that permits answering research questions of general importance by examining individuals in a comprehensive, whole-person manner. Discusses their use in two studies of persons with spinal cord injuries. (LLL)

  17. A Comparative Investigation of the Efficiency of Two Classroom Observational Methods.

    ERIC Educational Resources Information Center

    Kissel, Mary Ann

    The problem of this study was to determine whether Method A is a more efficient observational method for obtaining activity type behaviors in an individualized classroom than Method B. Method A requires the observer to record the activities of the entire class at given intervals while Method B requires only the activities of selected individuals…

  18. Optimized AVHRR land surface temperature downscaling method for local scale observations: case study for the coastal area of the Gulf of Gdańsk

    NASA Astrophysics Data System (ADS)

    Chybicki, Andrzej; Łubniewski, Zbigniew

    2017-09-01

    Satellite imaging systems have known limitations regarding their spatial and temporal resolution. The approaches based on subpixel mapping of the Earth's environment, which rely on combining the data retrieved from sensors of higher temporal and lower spatial resolution with the data characterized by lower temporal but higher spatial resolution, are of considerable interest. The paper presents the downscaling process of the land surface temperature (LST) derived from low resolution imagery acquired by the Advanced Very High Resolution Radiometer (AVHRR), using the inverse technique. The effective emissivity derived from another data source is used as a quantity describing thermal properties of the terrain in higher resolution, and allows the downsampling of low spatial resolution LST images. The authors propose an optimized downscaling method formulated as the inverse problem and show that the proposed approach yields better results than the use of other downsampling methods. The proposed method aims to find estimation of high spatial resolution LST data by minimizing the global error of the downscaling. In particular, for the investigated region of the Gulf of Gdansk, the RMSE between the AVHRR image downscaled by the proposed method and the Landsat 8 LST reference image was 2.255°C with correlation coefficient R equal to 0.828 and Bias = 0.557°C. For comparison, using the PBIM method, it was obtained RMSE = 2.832°C, R = 0.775 and Bias = 0.997°C for the same satellite scene. It also has been shown that the obtained results are also good in local scale and can be used for areas much smaller than the entire satellite imagery scene, depicting diverse biophysical conditions. Specifically, for the analyzed set of small sub-datasets of the whole scene, the obtained RSME between the downscaled and reference image was smaller, by approx. 0.53°C on average, in the case of applying the proposed method than in the case of using the PBIM method.

  19. Do the methods used to analyse missing data really matter? An examination of data from an observational study of Intermediate Care patients.

    PubMed

    Kaambwa, Billingsley; Bryan, Stirling; Billingham, Lucinda

    2012-06-27

    Missing data is a common statistical problem in healthcare datasets from populations of older people. Some argue that arbitrarily assuming the mechanism responsible for the missingness and therefore the method for dealing with this missingness is not the best option-but is this always true? This paper explores what happens when extra information that suggests that a particular mechanism is responsible for missing data is disregarded and methods for dealing with the missing data are chosen arbitrarily. Regression models based on 2,533 intermediate care (IC) patients from the largest evaluation of IC done and published in the UK to date were used to explain variation in costs, EQ-5D and Barthel index. Three methods for dealing with missingness were utilised, each assuming a different mechanism as being responsible for the missing data: complete case analysis (assuming missing completely at random-MCAR), multiple imputation (assuming missing at random-MAR) and Heckman selection model (assuming missing not at random-MNAR). Differences in results were gauged by examining the signs of coefficients as well as the sizes of both coefficients and associated standard errors. Extra information strongly suggested that missing cost data were MCAR. The results show that MCAR and MAR-based methods yielded similar results with sizes of most coefficients and standard errors differing by less than 3.4% while those based on MNAR-methods were statistically different (up to 730% bigger). Significant variables in all regression models also had the same direction of influence on costs. All three mechanisms of missingness were shown to be potential causes of the missing EQ-5D and Barthel data. The method chosen to deal with missing data did not seem to have any significant effect on the results for these data as they led to broadly similar conclusions with sizes of coefficients and standard errors differing by less than 54% and 322%, respectively. Arbitrary selection of methods to deal

  20. Using a Harmonic Scalpel "Drilling and Clamping" Method to Implement Zero Ischemic Robotic-assisted Partial Nephrectomy: An Observation Case Report Study.

    PubMed

    Hou, Chen-Pang; Lin, Yu-Hsiang; Hsu, Yu-Chao; Chen, Chien-Lun; Chang, Phei-Lang; Tsui, Ke-Hung

    2016-01-01

    Robot-assisted partial nephrectomy (RAPN) has gradually become a popular minimally invasive nephron-sparing surgical option for small renal tumors. Ischemic injury should be minimized because it impacts renal function outcomes following partial nephrectomy. Herein, the authors detail the technique and present initial perioperative outcomes of our novel harmonic scalpel "drilling and clamping" method to implement zero-ischemic RAPN. The authors prospectively collected baseline and perioperative data of patients who underwent zero ischemic RAPN performed by our harmonic scalpel "drilling and clamping" method. From April 2012 to December 2014, a total of 19 consecutive zero ischemic RAPN procedures were performed by a single surgeon. For 18 of the 19 patients, RAPN using our harmonic scalpel "Drilling and Clamping" method was successfully completed without the need for hilar clamping. The median tumor size was 3.4 cm (range: 1.8-6.2); operative time was 3.2 hours (range: 1.9-4.5); blood loss was 100 mL (range: 30-950); and postoperative hospital stay was 4 days (3-26). One patient required intraoperative blood transfusion. Two patients had intra or postoperative complications: 1 was converted to traditional laparotomy because of massive bleeding, whereas another had postoperative stress ulcer. Pathology confirmed renal cell carcinoma in 13 patients (63.2%), angiomyolipoma in 6 patients: (31.5%), and oncocytoma in 1 patient (5.3%). Mean pre- and postoperative serum creatinine (0.82 mg/dL and 0.85 mg/dL, respectively), estimated glomerular filtration rate (84.12 and 82.18, respectively), and hemoglobin (13.27 g/dL and 12.71 g/dL, respectively) were comparable. The authors present a novel zero-ischemic technique for RAPN. They believe that this technique is feasible and reproducible.

  1. Emerging Methods and Systems for Observing Life in the Sea

    NASA Astrophysics Data System (ADS)

    Chavez, F.; Pearlman, J.; Simmons, S. E.

    2016-12-01

    There is a growing need for observations of life in the sea at time and space scales consistent with those made for physical and chemical parameters. International programs such as the Global Ocean Observing System (GOOS) and Marine Biodiversity Observation Networks (MBON) are making the case for expanded biological observations and working diligently to prioritize essential variables. Here we review past, present and emerging systems and methods for observing life in the sea from the perspective of maintaining continuous observations over long time periods. Methods that rely on ships with instrumentation and over-the-side sample collections will need to be supplemented and eventually replaced with those based from autonomous platforms. Ship-based optical and acoustic instruments are being reduced in size and power for deployment on moorings and autonomous vehicles. In parallel a new generation of low power, improved resolution sensors are being developed. Animal bio-logging is evolving with new, smaller and more sophisticated tags being developed. New genomic methods, capable of assessing multiple trophic levels from a single water sample, are emerging. Autonomous devices for genomic sample collection are being miniaturized and adapted to autonomous vehicles. The required processing schemes and methods for these emerging data collections are being developed in parallel with the instrumentation. An evolving challenge will be the integration of information from these disparate methods given that each provides their own unique view of life in the sea.

  2. 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.

  3. A Study of the Use of the Three-Minute Classrooom Walk-Through Observation Method for Determining the Implementation of New Instructional Strategies

    ERIC Educational Resources Information Center

    Notgrass, Patty J.

    2012-01-01

    Principals are responsible for ensuring the effectiveness of the instructional programs, including staff development, on their campuses. Instructional leaders must utilize practices that allow them to fulfill this responsibility. This qualitative, collective case study examined the effectiveness of the three-minute classroom walk-through…

  4. Effects of creative and social activity on the health and well-being of socially isolated older people: outcomes from a multi-method observational study.

    PubMed

    Greaves, Colin J; Farbus, Lou

    2006-05-01

    Depression and social isolation affect one in seven people over 65 and there is increasing recognition that social isolation adversely affects long-term health. Research indicates that interventions, which promote active social contact, which encourage creativity, and which use mentoring, are more likely to positively affect health and well-being. The purpose of this study was to evaluate a complex intervention for addressing social isolation in older people, embodying these principles: The Upstream Healthy Living Centre. Mentors delivered a series of individually-tailored activities, with support tailing off over time. Two hundred and twenty-nine participants were offered the Geriatric Depression Scale, SF12 Health Quality of Life, and Medical Outcomes Social Support scale at baseline, then 6 months and 12 months post intervention. Semi-structured interviews were conducted with 26 participants, five carers and four referring health professionals to provide a deeper understanding of outcomes. Data were available for 172 (75%) participants at baseline, 72 (53% of those eligible) at 6 months and 51 (55%) at 12 months. Baseline scores indicated social isolation and high morbidity for mental and physical health. The intervention was successful in engaging this population (80% of referrals were engaged in some form of activity). At 6 months, there were significant improvements in SF12 mental component, and depression scores, but not in perceived physical health or social support. At 12 months, there were significant improvements in depression and social support and a marginally significant improvement in SF12 physical component (p = 0.06), but the SF12 mental component change was not maintained. The qualitative data showed that the intervention was well-received by participants. The data indicated a wide range of responses (both physical and emotional), including increased alertness, social activity, self-worth, optimism about life, and positive changes in health

  5. Observations of Bacterial Behavior during Infection Using the ARGOS Method

    NASA Astrophysics Data System (ADS)

    Charest, A. J.; Algarni, S.; Iannacchione, G. S.

    2015-03-01

    This research employed the Area Recorded Generalized Optical Scattering (ARGOS) approach which allowed for the observation of bacterial changes in terms of individual particles and population dynamics in real time. This new approach allows for an aqueous environment to be manipulated while conducting time-specific measurements over an indefinite amount of time. This current study provides a more time-specific method in which the bacteria remained within the initial conditions and allows for more time precision than provided by analyzing concentrations of plaque-forming units (PFU). This study involved the bacteria (F-amp) during infection by bacteriophage (MS2). The relative total intensity allows for detailed measurements of the bacteria population over time. The bacteria characteristics were also evaluated such as the root mean square image difference (at specific wavevectors), fractal dimension and effective radius. The growth rate of the infected bacteria occurred at a rate higher than the uninfected bacteria similarly, the death rates were also higher for the infected bacteria than the uninfected bacteria. The present study indicates that bacteria may react to infection by increasing the rate of population growth.

  6. Cultivating cohort studies for observational translational research.

    PubMed

    Ransohoff, David F

    2013-04-01

    "Discovery" research about molecular markers for diagnosis, prognosis, or prediction of response to therapy has frequently produced results that were not reproducible in subsequent studies. What are the reasons, and can observational cohorts be cultivated to provide strong and reliable answers to those questions? Experimental Selected examples are used to illustrate: (i) what features of research design provide strength and reliability in observational studies about markers of diagnosis, prognosis, and response to therapy? (ii) How can those design features be cultivated in existing observational cohorts, for example, within randomized controlled clinical trial (RCT), other existing observational research studies, or practice settings like health maintenance organization (HMOs)? Examples include a study of RNA expression profiles of tumor tissue to predict prognosis of breast cancer, a study of serum proteomics profiles to diagnose ovarian cancer, and a study of stool-based DNA assays to screen for colon cancer. Strengths and weaknesses of observational study design features are discussed, along with lessons about how features that help assure strength might be "cultivated" in the future. By considering these examples and others, it may be possible to develop a process of "cultivating cohorts" in ongoing RCTs, observational cohort studies, and practice settings like HMOs that have strong features of study design. Such an effort could produce sources of data and specimens to reliably answer questions about the use of molecular markers in diagnosis, prognosis, and response to therapy.

  7. Using Observational Methods to Research the Student Experience

    ERIC Educational Resources Information Center

    Cotton, Debby R. E.; Stokes, Alison; Cotton, Peter A.

    2010-01-01

    Much pedagogic research undertaken in geography and other disciplines relies on post-hoc methods such as surveys or interviews to investigate the student experience of higher education (often based on self-reports of behaviour). However, observation of students provides a far more direct route to obtain information about their behaviour, and there…

  8. Observed Methods for Felling Hardwood Trees with Chain Saws

    Treesearch

    Jerry L. Koger

    1983-01-01

    The angles and lengths of the cutting surfaces made by chain saw operators on hardwood tree stumps are described by means, standard deviations, ranges, and regression equations. Recommended felling guidelines are compared with observed felling methods used by experienced timber cutters in the southern Appalachian Mountains.

  9. Method for observing phase objects without halos and directional shadows

    NASA Astrophysics Data System (ADS)

    Suzuki, Yoshimasa; Kajitani, Kazuo; Ohde, Hisashi

    2015-03-01

    A new microscopy method for observing phase objects without halos and directional shadows is proposed. The key optical element is an annular aperture at the front focal plane of a condenser with a larger diameter than those used in standard phase contrast microscopy. The light flux passing through the annular aperture is changed by the specimen's surface profile and then passes through an objective and contributes to image formation. This paper presents essential conditions for realizing the method. In this paper, images of colonies formed by induced pluripotent stem (iPS) cells using this method are compared with the conventional phase contrast method and the bright-field method when the NA of the illumination is small to identify differences among these techniques. The outlines of the iPS cells are clearly visible with this method, whereas they are not clearly visible due to halos when using the phase contrast method or due to weak contrast when using the bright-field method. Other images using this method are also presented to demonstrate a capacity of this method: a mouse ovum and superimposition of several different images of mouse iPS cells.

  10. 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".

  11. 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.

  12. Community Engagement in Observational Human Exposure Studies

    EPA Science Inventory

    Although observational human exposure studies do not deliberately expose participants to chemicals or environmental conditions, merely involving people as research participants and conducting research inside homes raises ethical issues. Community engagement offers a promising st...

  13. Applying Nyquist's method for stability determination to solar wind observations

    NASA Astrophysics Data System (ADS)

    Klein, Kristopher G.; Kasper, Justin C.; Korreck, K. E.; Stevens, Michael L.

    2017-10-01

    The role instabilities play in governing the evolution of solar and astrophysical plasmas is a matter of considerable scientific interest. The large number of sources of free energy accessible to such nearly collisionless plasmas makes general modeling of unstable behavior, accounting for the temperatures, densities, anisotropies, and relative drifts of a large number of populations, analytically difficult. We therefore seek a general method of stability determination that may be automated for future analysis of solar wind observations. This work describes an efficient application of the Nyquist instability method to the Vlasov dispersion relation appropriate for hot, collisionless, magnetized plasmas, including the solar wind. The algorithm recovers the familiar proton temperature anisotropy instabilities, as well as instabilities that had been previously identified using fits extracted from in situ observations in Gary et al. (2016). Future proposed applications of this method are discussed.

  14. 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.

  15. A Fast Radio Burst Search Method for VLBI Observation

    NASA Astrophysics Data System (ADS)

    Liu, Lei; Tong, Fengxian; Zheng, Weimin; Zhang, Juan; Tong, Li

    2018-02-01

    We introduce the cross-spectrum-based fast radio burst (FRB) search method for Very Long Baseline Interferometer (VLBI) observation. This method optimizes the fringe fitting scheme in geodetic VLBI data post-processing, which fully utilizes the cross-spectrum fringe phase information and therefore maximizes the power of single-pulse signals. Working with cross-spectrum greatly reduces the effect of radio frequency interference compared with using auto-power spectrum. Single-pulse detection confidence increases by cross-identifying detections from multiple baselines. By combining the power of multiple baselines, we may improve the detection sensitivity. Our method is similar to that of coherent beam forming, but without the computational expense to form a great number of beams to cover the whole field of view of our telescopes. The data processing pipeline designed for this method is easy to implement and parallelize, which can be deployed in various kinds of VLBI observations. In particular, we point out that VGOS observations are very suitable for FRB search.

  16. An observational assessment method for aging laboratory rats

    EPA Science Inventory

    The growth of the aging population highlights the need for laboratory animal models to study the basic biological processes ofaging and susceptibility to toxic chemicals and disease. Methods to evaluate health ofaging animals over time are needed, especially efficient methods for...

  17. A roadside study of observable driver distractions.

    PubMed

    Sullman, Mark J M; Prat, Francesc; Tasci, Duygu Kuzu

    2015-01-01

    This study investigated the prevalence of observable distractions while driving and the effect of drivers' characteristics and time-related variables on their prevalence. Using roadside observation, 2 independent observers collected data at 4 randomly selected locations in St. Albans, UK. Of the 10,984 drivers observed, 16.8% were engaged in a secondary task, with talking to passengers being the most common distraction (8.8%), followed by smoking (1.9%) and talking on a hands-free mobile phone (1.7%). An additional 1.0% were observed talking on a handheld phone, and the rest of the distractions (e.g., texting, drinking) were recorded in less than 1% of the drivers observed. Gender-related differences were found for a number of different distractions (i.e., talking to passengers, drinking, and handheld mobile phone conversations), but age emerged as a significant predictor for most secondary tasks, including talking to passengers, smoking, hands-free mobile phone use, handheld mobile phone use, texting/keying numbers, drinking, and engagement in any type of distraction (all distractions combined). The overall pattern for age was that middle-aged and older drivers were less likely to be distracted than younger drivers. This work provides further evidence of the relatively high rate of distracted driving in the UK. The findings clearly indicate that younger drivers are more likely to drive distracted, which probably contributes to their higher crash rates.

  18. Benchmark Comparison of Cloud Analytics Methods Applied to Earth Observations

    NASA Technical Reports Server (NTRS)

    Lynnes, Chris; Little, Mike; Huang, Thomas; Jacob, Joseph; Yang, Phil; Kuo, Kwo-Sen

    2016-01-01

    Cloud computing has the potential to bring high performance computing capabilities to the average science researcher. However, in order to take full advantage of cloud capabilities, the science data used in the analysis must often be reorganized. This typically involves sharding the data across multiple nodes to enable relatively fine-grained parallelism. This can be either via cloud-based file systems or cloud-enabled databases such as Cassandra, Rasdaman or SciDB. Since storing an extra copy of data leads to increased cost and data management complexity, NASA is interested in determining the benefits and costs of various cloud analytics methods for real Earth Observation cases. Accordingly, NASA's Earth Science Technology Office and Earth Science Data and Information Systems project have teamed with cloud analytics practitioners to run a benchmark comparison on cloud analytics methods using the same input data and analysis algorithms. We have particularly looked at analysis algorithms that work over long time series, because these are particularly intractable for many Earth Observation datasets which typically store data with one or just a few time steps per file. This post will present side-by-side cost and performance results for several common Earth observation analysis operations.

  19. Benchmark Comparison of Cloud Analytics Methods Applied to Earth Observations

    NASA Astrophysics Data System (ADS)

    Lynnes, C.; Little, M. M.; Huang, T.; Jacob, J. C.; Yang, C. P.; Kuo, K. S.

    2016-12-01

    Cloud computing has the potential to bring high performance computing capabilities to the average science researcher. However, in order to take full advantage of cloud capabilities, the science data used in the analysis must often be reorganized. This typically involves sharding the data across multiple nodes to enable relatively fine-grained parallelism. This can be either via cloud-based filesystems or cloud-enabled databases such as Cassandra, Rasdaman or SciDB. Since storing an extra copy of data leads to increased cost and data management complexity, NASA is interested in determining the benefits and costs of various cloud analytics methods for real Earth Observation cases. Accordingly, NASA's Earth Science Technology Office and Earth Science Data and Information Systems project have teamed with cloud analytics practitioners to run a benchmark comparison on cloud analytics methods using the same input data and analysis algorithms. We have particularly looked at analysis algorithms that work over long time series, because these are particularly intractable for many Earth Observation datasets which typically store data with one or just a few time steps per file. This post will present side-by-side cost and performance results for several common Earth observation analysis operations.

  20. Workplace Education Initiative: Case Studies and Observations.

    ERIC Educational Resources Information Center

    Astrein, Bruce; And Others

    Seven workplace education projects funded in the first year of the Massachusetts Workplace Education Initiative are reported. This report includes both general observations and specific information in case studies of the projects. Overall information is provided on students served, the importance of partnerships, the emphasis on…

  1. Tire pressure special study : vehicle observation data

    DOT National Transportation Integrated Search

    2001-08-01

    Twenty seven percent of passenger cars with : regular passenger car tires have at least one : tire that is underinflated by 8 psi or more. : Tire Pressure Special Study: Vehicle : Observation Data is the third in a series of : research notes co...

  2. 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.

  3. 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

  4. Empirical Performance of Covariates in Education Observational Studies

    ERIC Educational Resources Information Center

    Wong, Vivian C.; Valentine, Jeffrey C.; Miller-Bains, Kate

    2017-01-01

    This article summarizes results from 12 empirical evaluations of observational methods in education contexts. We look at the performance of three common covariate-types in observational studies where the outcome is a standardized reading or math test. They are: pretest measures, local geographic matching, and rich covariate sets with a strong…

  5. A method for observing gas evolution during plastic laminate cure

    NASA Technical Reports Server (NTRS)

    Nicholls, A. H.

    1969-01-01

    Polyimide, phenolic, and other resins which develop volatiles during laminating or molding cure are studied using optimum cure cycles. The specimen is placed on a platen and sealed in a plastic bag, then heated and observed for gas evolution using a binocular microscope. A cover plate is added to sumulate an autoclave.

  6. Journalistic Observation as a Qualitative Research Method for Sociology.

    ERIC Educational Resources Information Center

    Burd, Gene

    A comparison is made between the tools of observation and research used by journalists to study society and the media, and the qualitative and clinical research tools used in the social and psychological sciences. The first part of the paper, a journalistic approach to sociology, traces the notion of the sociologist as a super-reporter using…

  7. Complications of local anaesthesia. An observational study.

    PubMed

    Brand, H S; Bekker, W; Baart, J A

    2009-11-01

    Local anaesthesia is increasingly used by dental hygienists. As little is known about the incidence of adverse effects during and after the administration of local anaesthetics, we evaluated side-effects associated with local anaesthesia. A prospective observational study was conducted using standard criteria among a group of 103 patients receiving mandibular block anaesthesia. Physical reactions like clenching fists (14.5%), moaning (12.6%) and turning pale (7.8%) were frequently observed. Patients (3.8%) showed a painful reaction because of needle contact with a nerve or the periosteum. Systemic complications were not observed. After the injection, 41.7% said they felt tense during the administration; 4.9% of the patients reported swallowing problems and 3.9% a tachycardia. These results suggest that administration of local anaesthesia has a small risk of adverse events. Complications, if they occur, seem minor and transient in nature.

  8. Observational studies of roAp stars

    NASA Astrophysics Data System (ADS)

    Sachkov, M.

    2014-11-01

    Rapidly oscillating Ap (roAp) stars are high-overtone, low-degree p-mode pulsators that are also chemically peculiar magnetic A stars. Until recently the classical asteroseismic analysis i.e. frequency analysis, of these stars was based on ground and space photometric observations. Significant progress was achieved through access to uninterrupted, ultra-high-precision data from MOST, COROT and Kepler satellites. Over the last ten years the study of roAp stars has been altered drastically from an observational point of view through studies of time-resolved, high-resolution spectra. Their unusual pulsational characteristics, caused by an interplay between the short vertical lengths of the pulsation waves and strong stratification of chemical elements, allow us to examine the upper roAp atmosphere in more detail than is possible for any star except the Sun. In this paper I review the results of recent studies of the pulsations of roAp stars.

  9. LONGITUDINAL COHORT METHODS STUDIES

    EPA Science Inventory

    Accurate exposure classification tools are required to link exposure with health effects in epidemiological studies. Exposure classification for occupational studies is relatively easy compared to predicting residential childhood exposures. Recent NHEXAS (Maryland) study articl...

  10. Determination of Reference Catalogs for Meridian Observations Using Statistical Method

    NASA Astrophysics Data System (ADS)

    Li, Z. Y.

    2014-09-01

    The meridian observational data are useful for developing high-precision planetary ephemerides of the solar system. These historical data are provided by the jet propulsion laboratory (JPL) or the Institut De Mecanique Celeste Et De Calcul Des Ephemerides (IMCCE). However, we find that the reference systems (realized by the fundamental catalogs FK3 (Third Fundamental Catalogue), FK4 (Fourth Fundamental Catalogue), and FK5 (Fifth Fundamental Catalogue), or Hipparcos), to which the observations are referred, are not given explicitly for some sets of data. The incompleteness of information prevents us from eliminating the systematic effects due to the different fundamental catalogs. The purpose of this paper is to specify clearly the reference catalogs of these observations with the problems in their records by using the JPL DE421 ephemeris. The data for the corresponding planets in the geocentric celestial reference system (GCRS) obtained from the DE421 are transformed to the apparent places with different hypothesis regarding the reference catalogs. Then the validations of the hypothesis are tested by two kinds of statistical quantities which are used to indicate the significance of difference between the original and transformed data series. As a result, this method is proved to be effective for specifying the reference catalogs, and the missed information is determined unambiguously. Finally these meridian data are transformed to the GCRS for further applications in the development of planetary ephemerides.

  11. 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.

  12. A method for combining passive microwave and infrared rainfall observations

    NASA Technical Reports Server (NTRS)

    Kummerow, Christian; Giglio, Louis

    1995-01-01

    Because passive microwave instruments are confined to polar-orbiting satellites, rainfall estimates must interpolate across long time periods, during which no measurements are available. In this paper the authors discuss a technique that allows one to partially overcome the sampling limitations by using frequent infrared observations from geosynchronous platforms. To accomplish this, the technique compares all coincident microwave and infrared observations. From each coincident pair, the infrared temperature threshold is selected that corresponds to an area equal to the raining area observed in the microwave image. The mean conditional rainfall rate as determined from the microwave image is then assigned to pixels in the infrared image that are colder than the selected threshold. The calibration is also applied to a fixed threshold of 235 K for comparison with established infrared techniques. Once a calibration is determined, it is applied to all infrared images. Monthly accumulations for both methods are then obtained by summing rainfall from all available infrared images. Two examples are used to evaluate the performance of the technique. The first consists of a one-month period (February 1988) over Darwin, Australia, where good validation data are available from radar and rain gauges. For this case it was found that the technique approximately doubled the rain inferred by the microwave method alone and produced exceptional agreement with the validation data. The second example involved comparisons with atoll rain gauges in the western Pacific for June 1989. Results here are overshadowed by the fact that the hourly infrared estimates from established techniques, by themselves, produced very good correlations with the rain gauges. The calibration technique was not able to improve upon these results.

  13. Ozone Lidar Observations for Air Quality Studies

    NASA Technical Reports Server (NTRS)

    Wang, Lihua; Newchurch, Mike; Kuang, Shi; Burris, John F.; Huang, Guanyu; Pour-Biazar, Arastoo; Koshak, William; Follette-Cook, Melanie B.; Pickering, Kenneth E.; McGee, Thomas J.; hide

    2015-01-01

    Tropospheric ozone lidars are well suited to measuring the high spatio-temporal variability of this important trace gas. Furthermore, lidar measurements in conjunction with balloon soundings, aircraft, and satellite observations provide substantial information about a variety of atmospheric chemical and physical processes. Examples of processes elucidated by ozone-lidar measurements are presented, and modeling studies using WRF-Chem, RAQMS, and DALES/LES models illustrate our current understanding and shortcomings of these processes.

  14. Methods of Studying Persons.

    ERIC Educational Resources Information Center

    Heinemann, Allen W.; Shontz, Franklin C.

    Conventional research strategies typically emphasize behavior-determining tendencies so strongly that the person as a whole is ignored. Research strategies for studying whole persons focus on symbolic structures, formulate specific questions in advance, study persons one at a time, use individualized measures, and regard participants as expert…

  15. Advanced Earth Observation System Instrumentation Study (aeosis)

    NASA Technical Reports Server (NTRS)

    White, R.; Grant, F.; Malchow, H.; Walker, B.

    1975-01-01

    Various types of measurements were studied for estimating the orbit and/or attitude of an Earth Observation Satellite. An investigation was made into the use of known ground targets in the earth sensor imagery, in combination with onboard star sightings and/or range and range rate measurements by ground tracking stations or tracking satellites (TDRSS), to estimate satellite attitude, orbital ephemeris, and gyro bias drift. Generalized measurement equations were derived for star measurements with a particular type of star tracker, and for landmark measurements with a multispectral scanner being proposed for an advanced Earth Observation Satellite. The use of infra-red horizon measurements to estimate the attitude and gyro bias drift of a geosynchronous satellite was explored.

  16. An Observational Study of Cataclysmic Variable Evolution

    NASA Astrophysics Data System (ADS)

    Araujo-Betancor, Sofia

    2004-03-01

    In this thesis I present an observational study of the evolution of Cataclysmic Variables (CVs). Disrupted magnetic braking has been the standard paradigm of CV evolution for the past twenty years. Unfortunately, some of its predictions are in strong disagreement with the observations. In recent years, a number of additions/alternatives to the standard model have been proposed. Yet, none have been able to explain all of the features observed in the currently known CV population. The work presented in this thesis is based mainly on a large-scale search for CVs. The primary aim of this project is to resolve the disagreement between theory and observations by eliminating the observational biases of the present CV sample. Here, I use two complementary approaches to search for CVs: (1) from the spectroscopic appearance in the Hamburg Quasar Survey (HQS), and (2) by using a combination of ROSAT and 2MASS archival data. So far, we have discovered 52 new CVs in the HQS and 11 new CVs (the majority of them magnetic) and 1 pre-CV in the ROSAT/2MASS. Follow-up observations of two newly discovered HQS CVs, 1RXS J062518.2+733433 and HS 2331+3905, resulted in the classification of the first as an Intermediate Polar, with P_orb = 283.0 min and P_spin = 19.8 min, and the second as a short orbital period system, P_orb = 81.0 min, harbouring a white dwarf pulsator. In addition, we found that the dominant ~3.5 h radial velocity variation of HS 2331+3905 does not correspond to the orbital period of the system, contrary to all other CVs. Despite its novel selection criterion, the HQS does not provide many short-period CVs -- even though tests with the known CVs included in the survey have shown that it is very sensitive to those objects. The biggest surprise in the new HQS sample is the discovery of many new SW Sex stars. The clustering of SW Sex stars in the 3-4 h period range is probably an important feature in the evolution of CVs that we currently do not understand at all. To

  17. Assessing the Accuracy of Classwide Direct Observation Methods: Two Analyses Using Simulated and Naturalistic Data

    ERIC Educational Resources Information Center

    Dart, Evan H.; Radley, Keith C.; Briesch, Amy M.; Furlow, Christopher M.; Cavell, Hannah J.; Briesch, Amy M.

    2016-01-01

    Two studies investigated the accuracy of eight different interval-based group observation methods that are commonly used to assess the effects of classwide interventions. In Study 1, a Microsoft Visual Basic program was created to simulate a large set of observational data. Binary data were randomly generated at the student level to represent…

  18. The NOAA Satellite Observing System Architecture Study

    NASA Technical Reports Server (NTRS)

    Volz, Stephen; Maier, Mark; Di Pietro, David

    2016-01-01

    NOAA is beginning a study, the NOAA Satellite Observing System Architecture (NSOSA) study, to plan for the future operational environmental satellite system that will follow GOES and JPSS, beginning about 2030. This is an opportunity to design a modern architecture with no pre-conceived notions regarding instruments, platforms, orbits, etc. The NSOSA study will develop and evaluate architecture alternatives to include partner and commercial alternatives that are likely to become available. The objectives will include both functional needs and strategic characteristics (e.g., flexibility, responsiveness, sustainability). Part of this study is the Space Platform Requirements Working Group (SPRWG), which is being commissioned by NESDIS. The SPRWG is charged to assess new or existing user needs and to provide relative priorities for observational needs in the context of the future architecture. SPRWG results will serve as input to the process for new foundational (Level 0 and Level 1) requirements for the next generation of NOAA satellites that follow the GOES-R, JPSS, DSCOVR, Jason-3, and COSMIC-2 missions.

  19. Globally Gridded Satellite observations for climate studies

    USGS Publications Warehouse

    Knapp, K.R.; Ansari, S.; Bain, C.L.; Bourassa, M.A.; Dickinson, M.J.; Funk, Chris; Helms, C.N.; Hennon, C.C.; Holmes, C.D.; Huffman, G.J.; Kossin, J.P.; Lee, H.-T.; Loew, A.; Magnusdottir, G.

    2011-01-01

    Geostationary satellites have provided routine, high temporal resolution Earth observations since the 1970s. Despite the long period of record, use of these data in climate studies has been limited for numerous reasons, among them that no central archive of geostationary data for all international satellites exists, full temporal and spatial resolution data are voluminous, and diverse calibration and navigation formats encumber the uniform processing needed for multisatellite climate studies. The International Satellite Cloud Climatology Project (ISCCP) set the stage for overcoming these issues by archiving a subset of the full-resolution geostationary data at ~10-km resolution at 3-hourly intervals since 1983. Recent efforts at NOAA's National Climatic Data Center to provide convenient access to these data include remapping the data to a standard map projection, recalibrating the data to optimize temporal homogeneity, extending the record of observations back to 1980, and reformatting the data for broad public distribution. The Gridded Satellite (GridSat) dataset includes observations from the visible, infrared window, and infrared water vapor channels. Data are stored in Network Common Data Format (netCDF) using standards that permit a wide variety of tools and libraries to process the data quickly and easily. A novel data layering approach, together with appropriate satellite and file metadata, allows users to access GridSat data at varying levels of complexity based on their needs. The result is a climate data record already in use by the meteorological community. Examples include reanalysis of tropical cyclones, studies of global precipitation, and detection and tracking of the intertropical convergence zone.

  20. Overview of the Ocean Observer Satellite Study

    NASA Astrophysics Data System (ADS)

    Cunningham, J. D.; McGuire, J. P.; Pichel, W. G.; Gerber, A. J.

    2002-12-01

    A two-year study of ocean satellite remote sensing requirements and instrument/satellite options is nearing completion. This Ocean Observer Study was sponsored by the U.S. Dept. of Commerce/Dept. of Defense/National Aeronautics and Space Administration Integrated Program Office, whose mission is to develop the future U.S. National Polar-Orbiting Operational Environmental Satellite System (NPOESS). A comprehensive Ocean Observer User Requirements Document has been drafted by a team of over 150 government, academic, and private sector scientists, engineers, and administrators. Included are requirements for open and coastal ocean surface, cryospheric, hydrologic, and some land/hazard and atmospheric boundary layer parameters. This document was then used as input to the instrument and satellite study (conducted by the Jet Propulsion Laboratory) which produced five different instrument/satellite configuration options designed to address the maximum number of requirements which will not be met with the already-approved NPOESS instruments. Instruments studied include a synthetic aperture radar (SAR), an altimeter, and a hyper-spectral coastal infrared/visible imager. After analyzing the alternatives, it appears that one of the best options is a two-satellite system consisting of (1) an altimeter mission in the Topex/Poseidon orbit carrying both wide-swath and delayed doppler altimeters, and (2) a multi-polarization, multi-frequency, multi-mode interferometric SAR mission including a coastal imager in a polar sun-synchronous orbit. This paper summarizes the user requirements process, briefly describes the notional satellite configuration, and presents some of the capabilities of the instruments.

  1. Development of a structured observational method for the systematic assessment of school food-choice architecture.

    PubMed

    Ozturk, Orgul D; McInnes, Melayne M; Blake, Christine E; Frongillo, Edward A; Jones, Sonya J

    2016-01-01

    The objective of this study is to develop a structured observational method for the systematic assessment of the food-choice architecture that can be used to identify key points for behavioral economic intervention intended to improve the health quality of children's diets. We use an ethnographic approach with observations at twelve elementary schools to construct our survey instrument. Elements of the structured observational method include decision environment, salience, accessibility/convenience, defaults/verbal prompts, number of choices, serving ware/method/packaging, and social/physical eating environment. Our survey reveals important "nudgeable" components of the elementary school food-choice architecture, including precommitment and default options on the lunch line.

  2. Evaluation of Two Methods for Modeling Measurement Errors When Testing Interaction Effects with Observed Composite Scores

    ERIC Educational Resources Information Center

    Hsiao, Yu-Yu; Kwok, Oi-Man; Lai, Mark H. C.

    2018-01-01

    Path models with observed composites based on multiple items (e.g., mean or sum score of the items) are commonly used to test interaction effects. Under this practice, researchers generally assume that the observed composites are measured without errors. In this study, we reviewed and evaluated two alternative methods within the structural…

  3. Evaluation of Inversion Methods Applied to Ionospheric ro Observations

    NASA Astrophysics Data System (ADS)

    Rios Caceres, Arq. Estela Alejandra; Rios, Victor Hugo; Guyot, Elia

    The new technique of radio-occultation can be used to study the Earth's ionosphere. The retrieval processes of ionospheric profiling from radio occultation observations usually assume spherical symmetry of electron density distribution at the locality of occultation and use the Abel integral transform to invert the measured total electron content (TEC) values. This pa-per presents a set of ionospheric profiles obtained from SAC-C satellite with the Abel inversion technique. The effects of the ionosphere on the GPS signal during occultation, such as bending and scintillation, are examined. Electron density profiles are obtained using the Abel inversion technique. Ionospheric radio occultations are validated using vertical profiles of electron con-centration from inverted ionograms , obtained from ionosonde sounding in the vicinity of the occultation. Results indicate that the Abel transform works well in the mid-latitudes during the daytime, but is less accurate during the night-time.

  4. Safety Alerts: An Observational Study in Portugal.

    PubMed

    Soares, Sara; Roque, Fátima; Teixeira Rodrigues, António; Figueiras, Adolfo; Herdeiro, Maria Teresa

    2015-09-01

    The information that is available when marketing authorizations are approved is limited. Pharmacovigilance has an important role during the postauthorization period, and alerts published by national authorities allow health care professionals to be informed about new data on safety profiles. This study therefore sought to analyze all safety alerts published by the Portuguese National Authority of Medicines and Health Products I.P. (INFARMED). We conducted an observational study of all alerts published on the INFARMED website from January 2002 through December 2014. From the data included in the alerts, the following information was abstracted: active substance name (and trade name), event that led to the alert, and the resulting safety measures. Active substances were classified according to the Anatomical Therapeutic Chemical (ATC) code. A total of 562 alerts were published, and 304 were eligible for inclusion. The musculoskeletal system was the ATC code with more alerts (n = 53), followed by the nervous system (n = 42). Communication of the information and recommendations to the health care professionals and the public in general was the most frequent safety measure (n = 128), followed by changes in the Summary of the Product Characteristics and package information leaflet (n = 66). During the study period, 26 marketing authorizations were temporarily suspended and 10 were revoked. The knowledge of the alerts published during the postmarketing period is very useful to the health care professionals for improving prescription and use of medicines and to the scientific community for the development of new researches. Copyright © 2015 Elsevier HS Journals, Inc. All rights reserved.

  5. 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

  6. Using video-based observation research methods in primary care health encounters to evaluate complex interactions

    PubMed Central

    Asan, Onur; Montague, Enid

    2015-01-01

    Objective The purpose of this paper is to describe the use of video-based observation research methods in primary care environment and highlight important methodological considerations and provide practical guidance for primary care and human factors researchers conducting video studies to understand patient-clinician interaction in primary care settings. Methods We reviewed studies in the literature which used video methods in health care research and, we also used our own experience based on the video studies we conducted in primary care settings. Results This paper highlighted the benefits of using video techniques such as multi-channel recording and video coding and compared “unmanned” video recording with the traditional observation method in primary care research. We proposed a list, which can be followed step by step to conduct an effective video study in a primary care setting for a given problem. This paper also described obstacles researchers should anticipate when using video recording methods in future studies. Conclusion With the new technological improvements, video-based observation research is becoming a promising method in primary care and HFE research. Video recording has been under-utilized as a data collection tool because of confidentiality and privacy issues. However, it has many benefits as opposed to traditional observations, and recent studies using video recording methods have introduced new research areas and approaches. PMID:25479346

  7. Five Methods to Score the Teacher Observation of Classroom Adaptation Checklist and to Examine Group Differences

    ERIC Educational Resources Information Center

    Wang, Ze; Rohrer, David; Chuang, Chi-ching; Fujiki, Mayo; Herman, Keith; Reinke, Wendy

    2015-01-01

    This study compared 5 scoring methods in terms of their statistical assumptions. They were then used to score the Teacher Observation of Classroom Adaptation Checklist, a measure consisting of 3 subscales and 21 Likert-type items. The 5 methods used were (a) sum/average scores of items, (b) latent factor scores with continuous indicators, (c)…

  8. Field Science Ethnography: Methods For Systematic Observation on an Expedition

    NASA Technical Reports Server (NTRS)

    Clancey, William J.; Clancy, Daniel (Technical Monitor)

    2001-01-01

    The Haughton-Mars expedition is a multidisciplinary project, exploring an impact crater in an extreme environment to determine how people might live and work on Mars. The expedition seeks to understand and field test Mars facilities, crew roles, operations, and computer tools. I combine an ethnographic approach to establish a baseline understanding of how scientists prefer to live and work when relatively unemcumbered, with a participatory design approach of experimenting with procedures and tools in the context of use. This paper focuses on field methods for systematically recording and analyzing the expedition's activities. Systematic photography and time-lapse video are combined with concept mapping to organize and present information. This hybrid approach is generally applicable to the study of modern field expeditions having a dozen or more multidisciplinary participants, spread over a large terrain during multiple field seasons.

  9. Partial Variance of Increments Method in Solar Wind Observations and Plasma Simulations

    NASA Astrophysics Data System (ADS)

    Greco, A.; Matthaeus, W. H.; Perri, S.; Osman, K. T.; Servidio, S.; Wan, M.; Dmitruk, P.

    2018-02-01

    The method called "PVI" (Partial Variance of Increments) has been increasingly used in analysis of spacecraft and numerical simulation data since its inception in 2008. The purpose of the method is to study the kinematics and formation of coherent structures in space plasmas, a topic that has gained considerable attention, leading the development of identification methods, observations, and associated theoretical research based on numerical simulations. This review paper will summarize key features of the method and provide a synopsis of the main results obtained by various groups using the method. This will enable new users or those considering methods of this type to find details and background collected in one place.

  10. Strengthening the reliability and credibility of observational epidemiology studies by creating an Observational Studies Register.

    PubMed

    Swaen, Gerard M H; Carmichael, Neil; Doe, John

    2011-05-01

    To evaluate the need for the creation of a system in which observational epidemiology studies are registered; an Observational Studies Register (OSR). The current scientific process for observational epidemiology studies is described. Next, a parallel is made with the clinical trials area, where the creation of clinical trial registers has greatly restored and improved their credibility and reliability. Next, the advantages and disadvantages of an OSR are compared. The advantages of an OSR outweigh its disadvantages. The creation of an OSR, similar to the existing Clinical Trials Registers, will improve the assessment of publication bias and will provide an opportunity to compare the original study protocol with the results reported in the publication. Reliability, credibility, and transparency of observational epidemiology studies are strengthened by the creation of an OSR. We propose a structured, collaborative, and coordinated approach for observational epidemiology studies that can provide solutions for existing weaknesses and will strengthen credibility and reliability, similar to the approach currently used in clinical trials, where Clinical Trials Registers have played a key role in strengthening their scientific value. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Comparison of Observational Methods and Their Relation to Ratings of Engagement in Young Children

    ERIC Educational Resources Information Center

    Wood, Brenna K.; Hojnoski, Robin L.; Laracy, Seth D.; Olson, Christopher L.

    2016-01-01

    Although, collectively, results of earlier direct observation studies suggest momentary time sampling (MTS) may offer certain technical advantages over whole-interval (WIR) and partial-interval (PIR) recording, no study has compared these methods for measuring engagement in young children in naturalistic environments. This study compared direct…

  12. Using video-based observation research methods in primary care health encounters to evaluate complex interactions.

    PubMed

    Asan, Onur; Montague, Enid

    2014-01-01

    The purpose of this paper is to describe the use of video-based observation research methods in primary care environment and highlight important methodological considerations and provide practical guidance for primary care and human factors researchers conducting video studies to understand patient-clinician interaction in primary care settings. We reviewed studies in the literature which used video methods in health care research, and we also used our own experience based on the video studies we conducted in primary care settings. This paper highlighted the benefits of using video techniques, such as multi-channel recording and video coding, and compared "unmanned" video recording with the traditional observation method in primary care research. We proposed a list that can be followed step by step to conduct an effective video study in a primary care setting for a given problem. This paper also described obstacles, researchers should anticipate when using video recording methods in future studies. With the new technological improvements, video-based observation research is becoming a promising method in primary care and HFE research. Video recording has been under-utilised as a data collection tool because of confidentiality and privacy issues. However, it has many benefits as opposed to traditional observations, and recent studies using video recording methods have introduced new research areas and approaches.

  13. HARBO, a simple computer-aided observation method for recording work postures.

    PubMed

    Wiktorin, C; Mortimer, M; Ekenvall, L; Kilbom, A; Hjelm, E W

    1995-12-01

    The aim of the study was to present an observation method focusing on the positions of the hands relative to the body and to evaluate whether this simple observation technique gives a reliable estimate of the total time spent in each of five work postures during one workday. In the first part of the study the interobserver reliability of the observation method was tested with eight blue-collar workers. In the second part the observed time spent with work above the shoulder level was tested in relation to an upper-arm position analyzer, and observed time spent in work below knuckle level was tested in relation to a trunk flexion analyzer, both with 72 blue-collar workers. The interobserver reliability for full-day registrations was high. The intraclass correlation coefficients ranged from 0.99 to 1.00. The observed duration of work with hands above shoulder level correlated well with the measured duration of pronounced arm elevation (> 75 degrees). The product moment correlation coefficient was 0.97. The observed duration of work with hands below knuckle level correlated well with the measured duration of pronounced trunk flexion angles (> 40 degrees). The product moment correlation coefficient was 0.98. The present observation method, designed to make postural observations continuously for several hours, is easy to learn and seems reliable.

  14. Late onset rheumatoid arthritis an observational study.

    PubMed

    Rexhepi, Sylejman; Rexhepi, Mjellma; Sahatçiu-Meka, Vjollca; Rexhepi, Blerta; Bahtiri, Elton; Mahmutaj, Vigan

    Rheumatoid arthritis (RA) may have an onset at older age. The onset of the disease at the age of 60 and over is called late-onset rheumatoid arthritis (LORA). The aim of this study was to analyze the clinical, laboratory, radiological, and treatment characteristics of patients with LORA compared to those with early-onset RA (EaORA), provided that all the patients had an approximately equal duration of the disease. This is an observational single-center study, which involved 120 patients with an established diagnosis of RA, of which 60 patients had LORA, and 60 patients EaORA. The disease activity, measured by the Disease Activity Score 28 (DAS28-ESR), was significantly higher in the LORA group compared to the EaORA group (p<0.05). Significantly more patients with LORA had involvement of the shoulders (LORA vs. EaORA, 30% vs. 15%; p <0.05) and knees (LORA vs. EaORA, 46.7% vs. 16.7%; p <0.05). Radiological erosive changes were significantly more frequent in the LORA group in comparison with EaORA (p <0.05). There was no difference between the groups regarding rheumatoid factor (RF) positivity (p>0.05), while the number of patients positive for anti-citrullinated protein antibody (ACPA) was signifi cantly greater in the EaORA group (p<0.05). The values of C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were significantly higher in the LORA than in the EaORA group. Hemoglobin levels were lower in the LORA group (11.96±1.64 g/dL) than in the EaORA group (12.18±1.56 g/dL). The most used disease-modifying antirheumatic drugs (DMARDs) were methotrexate and sulfasalazine, while biological drugs were not used. In conclusion, based on the results of our study, LORA has some features that distinguish it from EaORA, such as higher disease activity, more frequent involvement of large joints, and more pronounced structural damage. This should be taken in account in clinical practice, especially regarding treatment choices.

  15. Multicenter observational prehospital resuscitation on helicopter study.

    PubMed

    Holcomb, John B; Swartz, Michael D; DeSantis, Stacia M; Greene, Thomas J; Fox, Erin E; Stein, Deborah M; Bulger, Eileen M; Kerby, Jeffrey D; Goodman, Michael; Schreiber, Martin A; Zielinski, Martin D; O'Keeffe, Terence; Inaba, Kenji; Tomasek, Jeffrey S; Podbielski, Jeanette M; Appana, Savitri N; Yi, Misung; Wade, Charles E

    2017-07-01

    Earlier use of in-hospital plasma, platelets, and red blood cells (RBCs) has improved survival in trauma patients with severe hemorrhage. Retrospective studies have associated improved early survival with prehospital blood product transfusion (PHT). We hypothesized that PHT of plasma and/or RBCs would result in improved survival after injury in patients transported by helicopter. Adult trauma patients transported by helicopter from the scene to nine Level 1 trauma centers were prospectively observed from January to November 2015. Five helicopter systems had plasma and/or RBCs, whereas the other four helicopter systems used only crystalloid resuscitation. All patients meeting predetermined high-risk criteria were analyzed. Patients receiving PHT were compared with patients not receiving PHT. Our primary analysis compared mortality at 3 hours, 24 hours, and 30 days, using logistic regression to adjust for confounders and site heterogeneity to model patients who were matched on propensity scores. Twenty-five thousand one hundred eighteen trauma patients were admitted, 2,341 (9%) were transported by helicopter, of which 1,058 (45%) met the highest-risk criteria. Five hundred eighty-five of 1,058 patients were flown on helicopters carrying blood products. In the systems with blood available, prehospital median systolic blood pressure (125 vs 128) and Glasgow Coma Scale (7 vs 14) was significantly lower, whereas median Injury Severity Score was significantly higher (21 vs 14). Unadjusted mortality was significantly higher in the systems with blood products available, at 3 hours (8.4% vs 3.6%), 24 hours (12.6% vs 8.9%), and 30 days (19.3% vs 13.3%). Twenty-four percent of eligible patients received a PHT. A median of 1 unit of RBCs and plasma were transfused prehospital. Of patients receiving PHT, 24% received only plasma, 7% received only RBCs, and 69% received both. In the propensity score matching analysis (n = 109), PHT was not significantly associated with mortality

  16. Consent for pediatric anesthesia: an observational study.

    PubMed

    Lagana, Zoe; Foster, Andrew; Bibbo, Adriana; Dowling, Kate; Cyna, Allan M

    2012-08-01

    Informed consent prior to anesthesia is an important part of the pediatric pre-anesthetic consultation. This study aimed to observe and identify the number and nature of the anesthesia risks considered and communicated to parents/guardians and children during the pediatric informed consent process on the day of elective surgery. A convenience sample of anesthetists had their pre-anesthesia consultations voice recorded, prior to elective surgery, during a 4-month period at the largest tertiary referral centre for pediatric care in South Australia. A data collection form was used to note baseline demographic data, and voice recording transcripts were independently documented by two researchers and subsequently compared for accuracy regarding the number and nature of risks discussed. Of the 96 voice recordings, 91 (92%) were suitable for the analysis. The five most commonly discussed risks were as follows: nausea and vomiting (36%); sore throat (35%); allergy (29%); hypoxia (25%); and emergence delirium (19%). Twenty-seven pre-anesthetic consultations (30%) were found to have had no discussion of anesthetic risk at all while a further 23 consultations (26%) incorporated general statements inferring that anesthesia carried risks, but with no elaboration about their nature, ramifications or incidence. The median number of risks (IQR) specifically mentioned per consultation was higher, 3 (1) vs 1 (1), P < 0.05, when the consultation was performed by a trainee rather than a consultant anesthetist and when the patient had previous anesthesia experience odds ratio 0.34, 95% CI [0.13, 0.87], P = 0.025. The pediatric anesthesia risk discussion is very variable. Trainees tend to discuss more specific risks than consultants and a patient's previous experience of anesthesia was associated with a more limited discussion of anesthesia risk. © 2011 Blackwell Publishing Ltd.

  17. Century Scale Evaporation Trend: An Observational Study

    NASA Technical Reports Server (NTRS)

    Bounoui, Lahouari

    2012-01-01

    Several climate models with different complexity indicate that under increased CO2 forcing, runoff would increase faster than precipitation overland. However, observations over large U.S watersheds indicate otherwise. This inconsistency between models and observations suggests that there may be important feedbacks between climate and land surface unaccounted for in the present generation of models. We have analyzed century-scale observed annual runoff and precipitation time-series over several United States Geological Survey hydrological units covering large forested regions of the Eastern United States not affected by irrigation. Both time-series exhibit a positive long-term trend; however, in contrast to model results, these historic data records show that the rate of precipitation increases at roughly double the rate of runoff increase. We considered several hydrological processes to close the water budget and found that none of these processes acting alone could account for the total water excess generated by the observed difference between precipitation and runoff. We conclude that evaporation has increased over the period of observations and show that the increasing trend in precipitation minus runoff is correlated to observed increase in vegetation density based on the longest available global satellite record. The increase in vegetation density has important implications for climate; it slows but does not alleviate the projected warming associated with greenhouse gases emission.

  18. Improving Method-in-Use through Classroom Observation

    ERIC Educational Resources Information Center

    Nunn, Roger

    2011-01-01

    Method-in-use (Nunn, Describing classroom interaction in intercultural curricular research and development, University of Reading, 1996, International Review of Applied Linguistics in Language Teaching 37: 23-42, 1999) is a description of the method actually being enacted through classroom interaction in a particular context. The description is…

  19. A Genetic Algorithm Method for Direct estimation of paleostress states from heterogeneous fault-slip observations

    NASA Astrophysics Data System (ADS)

    Srivastava, D. C.

    2016-12-01

    A Genetic Algorithm Method for Direct estimation of paleostress states from heterogeneous fault-slip observationsDeepak C. Srivastava, Prithvi Thakur and Pravin K. GuptaDepartment of Earth Sciences, Indian Institute of Technology Roorkee, Roorkee 247667, India. Abstract Paleostress estimation from a group of heterogeneous fault-slip observations entails first the classification of the observations into homogeneous fault sets and then a separate inversion of each homogeneous set. This study combines these two issues into a nonlinear inverse problem and proposes a heuristic search method that inverts the heterogeneous fault-slip observations. The method estimates different paleostress states in a group of heterogeneous fault-slip observations and classifies it into homogeneous sets as a byproduct. It uses the genetic algorithm operators, elitism, selection, encoding, crossover and mutation. These processes translate into a guided search that finds successively fitter solutions and operate iteratively until the termination criteria is met and the globally fittest stress tensors are obtained. We explain the basic steps of the algorithm on a working example and demonstrate validity of the method on several synthetic and a natural group of heterogeneous fault-slip observations. The method is independent of any user-defined bias or any entrapment of solution in a local optimum. It succeeds even in the difficult situations where other classification methods are found to fail.

  20. Air quality: from observation to applied studies

    NASA Astrophysics Data System (ADS)

    Weber, Christiane H.; Wania, Annett; Hirsch, Jacky; Bruse, Michael

    2004-10-01

    Air qualities studies in urban areas embrace several directions that are strongly associated with urban complexity. In the last centuries cities evolution implied changes in urbanization trends: urban sprawl has modified the relationship between cities and surroundings settlements. The existence and protection of urban green and open areas is promoted as a mean to improve the quality of life of their citizens and increase the satisfactory level of the inhabitants against pollution and noise adverse effects. This paper outlines the methods and approaches used in the EU research project Benefits of Urban Green Space (BUGS). The main target of BUGS is to assess the role of urban green spaces in alleviating the adverse effects of urbanization trends by developing an integrative methodology, ranging from participatory planning tools to numerical simulation models. The influence of urban structures on atmospheric pollutants distribution is investigated as a multi-scale problem ranging from micro to macro/regional scale. Traditionally, air quality models are applied on a single scale, seldom considering the joint effects of traffic network and urban development together. In BUGS, several numerical models are applied to cope with urban complexity and to provide quantitative and qualitative results. The differing input data requirements for the various models demanded a methodology which ensures a coherent data extraction and application procedure. In this paper, the stepwise procedure used for BUGS is presented after a general presentation of the research project and the models implied. A discussion part will highlight the statements induced by the choices made and a conclusive part bring to the stage some insights for future investigations.

  1. Relative Efficiency of Several Methods of Direct Observation

    ERIC Educational Resources Information Center

    Kissel, Mary Ann; Yeager, John L.

    1972-01-01

    Conclusion is that it is not necessary to record the behavior of every pupil or an entire class in order to adequately measure a specific dimension of the classroom. Rather, observational efficiency can be attained through the utilization of sampling procedures for a given type of classroom situation. (Authors)

  2. [Therapeutic failure in scabies: An observational study].

    PubMed

    De Sainte Marie, B; Mallet, S; Gaudy-Marqueste, C; Baumstarck, K; Bentaleb, N; Loundou, A; Hesse, S; Monestier, S; Grob, J-J; Richard, M-A

    2016-01-01

    Several sources suggest an escalation of scabies in France. To describe a population of patients continuing to present with scabies despite multiple treatments in order to identify factors associated with persistence of infection. A descriptive cross-sectional study in adults and children consulting for persistent scabies despite at least one previous treatment. A standardized questionnaire explored potential sources of treatment failure. Thirty-one patients were analyzed. Initial symptoms were noted to have started between two and 52 weeks earlier (mean: 19 weeks). The mean number of prior consultations with a general practitioner was 3.1 (0-10) and 1.7 with a dermatologist (0-7). The mean number of patients per household was 3.5 (1-9). At least one dose of oral ivermectin (maximum of 6 doses per household) was prescribed for 84 % of patients (29 % of whom were not fasted at the time). Further, 74 % of patients received at least one local application of esdepallethrin and piperonyl butoxide (maximum: 5 courses), four received benzyl benzoate and two received permethrin; however, 58 % did not reapply the substance after hand washing. All households bought the prescribed treatments despite the costs. Close contacts of patients were treated in 58 % of households. Decontamination of bedding and clothing was carried out properly in 90 % of households. Persistence of infection appears to be linked to: (1) insufficient treatment of close contacts; (2) absence of a second treatment between days 7 and 14; (3) insufficient efficacy of the available treatments, doubtless due to multiple factors (intrinsic resistance of Sarcoptes, failure to repeat treatment, poor explanation of methods for dosing and application, and oral intake of treatments). Access to non-reimbursed treatments was not identified as a problem and decontamination of bedding and clothing was correctly performed in most cases. Though certain fundamental aspects of scabies treatment must be better

  3. Issues of reporting in observational studies in veterinary medicine.

    PubMed

    Sargeant, Jan M; O'Connor, Annette M

    2014-02-15

    Observational studies are common in veterinary medicine; the results may be used to inform decision-making, future research, or as inputs to systematic reviews or risk assessment. To be of use, the results must be published, all of the outcomes that were assessed must be included in the publication, and the research (methods and results) must be reported in sufficient detail that the reader can evaluate the internal and external validity. In human healthcare, concerns about the completeness of reporting - and evidence that poor reporting is associated with study results - have led to the creation of reporting guidelines; these include the STROBE statement for observational studies. There is evidence from a limited body of research that there also are reporting inadequacies in veterinary observational studies. There are differences between human and veterinary observational studies that might be relevant to recommendations for reporting. Such differences include: the use of observational studies in animal populations for simultaneously estimating disease frequency and risk-factor identification; the distinction between the animal owners who consent to participate and the animals that are the study subjects; and the complexity of organizational levels inherent in animal research (in particular, for studies in livestock species). In veterinary medicine, it is common to have clustering within outcomes (due to animal grouping) and clustering of predictor variables. We argue that there is a compelling need for the scientific community involved in veterinary observational studies to use the STROBE statement, use an amended version of STROBE, or to develop and use reporting guidelines that are specific to veterinary medicine to improve reporting of these studies. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. 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.

  5. A picture's worth a thousand words: a food-selection observational method.

    PubMed

    Carins, Julia E; Rundle-Thiele, Sharyn R; Parkinson, Joy E

    2016-05-04

    Issue addressed: Methods are needed to accurately measure and describe behaviour so that social marketers and other behaviour change researchers can gain consumer insights before designing behaviour change strategies and so, in time, they can measure the impact of strategies or interventions when implemented. This paper describes a photographic method developed to meet these needs. Methods: Direct observation and photographic methods were developed and used to capture food-selection behaviour and examine those selections according to their healthfulness. Four meals (two lunches and two dinners) were observed at a workplace buffet-style cafeteria over a 1-week period. The healthfulness of individual meals was assessed using a classification scheme developed for the present study and based on the Australian Dietary Guidelines. Results: Approximately 27% of meals (n = 168) were photographed. Agreement was high between raters classifying dishes using the scheme, as well as between researchers when coding photographs. The subset of photographs was representative of patterns observed in the entire dining room. Diners chose main dishes in line with the proportions presented, but in opposition to the proportions presented for side dishes. Conclusions: The present study developed a rigorous observational method to investigate food choice behaviour. The comprehensive food classification scheme produced consistent classifications of foods. The photographic data collection method was found to be robust and accurate. Combining the two observation methods allows researchers and/or practitioners to accurately measure and interpret food selections. Consumer insights gained suggest that, in this setting, increasing the availability of green (healthful) offerings for main dishes would assist in improving healthfulness, whereas other strategies (e.g. promotion) may be needed for side dishes. So what?: Visual observation methods that accurately measure and interpret food

  6. 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.

  7. Observer Rated Sleepiness and Real Road Driving: An Explorative Study

    PubMed Central

    Anund, Anna; Fors, Carina; Hallvig, David; Åkerstedt, Torbjörn; Kecklund, Göran

    2013-01-01

    The aim of the present study was to explore if observer rated sleepiness (ORS) is a feasible method for quantification of driver sleepiness in field studies. Two measures of ORS were used: (1) one for behavioural signs based on facial expression, body gestures and body movements labelled B-ORS, and (2) one based on driving performance e.g. if swerving and other indicators of impaired driving occurs, labelled D-ORS. A limited number of observers sitting in the back of an experimental vehicle on a motorway about 2 hours repeatedly 3 times per day (before lunch, after lunch, at night) observed 24 participant’s sleepiness level with help of the two observer scales. At the same time the participant reported subjective sleepiness (KSS), EOG was recorded (for calculation of blink duration) and several driving measure were taken and synchronized with the reporting. Based on mixed model Anova and correlation analysis the result showed that observer ratings of sleepiness based on drivers’ impaired performance and behavioural signs are sensitive to extend the general pattern of time awake, circadian phase and time of driving. The detailed analysis of the subjective sleepiness and ORS showed weak correspondence on an individual level. Only 16% of the changes in KSS were predicted by the observer. The correlation between the observer ratings based on performance (D-ORS) and behavioural signs (B-ORS) are high (r = .588), and the B-ORS shows a moderately strong association (r = .360) with blink duration. Both ORS measures show an association (r>0.45) with KSS, whereas the association with driving performance is weak. The results show that the ORS-method detects the expected general variations in sleepy driving in field studies, however, sudden changes in driver sleepiness on a detailed level as 5 minutes is usually not detected; this holds true both when taking into account driving behaviour or driver behavioural signs. PMID:23724094

  8. Inter- and intra- observer reliability of risk assessment of repetitive work without an explicit method.

    PubMed

    Eliasson, Kristina; Palm, Peter; Nyman, Teresia; Forsman, Mikael

    2017-07-01

    A common way to conduct practical risk assessments is to observe a job and report the observed long term risks for musculoskeletal disorders. The aim of this study was to evaluate the inter- and intra-observer reliability of ergonomists' risk assessments without the support of an explicit risk assessment method. Twenty-one experienced ergonomists assessed the risk level (low, moderate, high risk) of eight upper body regions, as well as the global risk of 10 video recorded work tasks. Intra-observer reliability was assessed by having nine of the ergonomists repeat the procedure at least three weeks after the first assessment. The ergonomists made their risk assessment based on his/her experience and knowledge. The statistical parameters of reliability included agreement in %, kappa, linearly weighted kappa, intraclass correlation and Kendall's coefficient of concordance. The average inter-observer agreement of the global risk was 53% and the corresponding weighted kappa (K w ) was 0.32, indicating fair reliability. The intra-observer agreement was 61% and 0.41 (K w ). This study indicates that risk assessments of the upper body, without the use of an explicit observational method, have non-acceptable reliability. It is therefore recommended to use systematic risk assessment methods to a higher degree. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Potential New Lidar Observations for Cloud Studies

    NASA Technical Reports Server (NTRS)

    Winker, Dave; Hu, Yong; Narir, Amin; Cai, Xia

    2015-01-01

    The response of clouds to global warming represents a major uncertainty in estimating climate sensitivity. These uncertainties have been tracked to shallow marine clouds in the tropics and subtropics. CALIOP observations have already been used extensively to evaluate model predictions of shallow cloud fraction and top height (Leahy et al. 2013; Nam et al 2012). Tools are needed to probe the lowest levels of the troposphere. The large footprint of satellite lidars gives large multiple scattering from clouds which presents new possibilities for cloud retrievals to constrain model predictions.

  10. 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

  11. Advanced Earth Observation System Instrumentation Study (AEOSIS)

    NASA Technical Reports Server (NTRS)

    Var, R. E.

    1976-01-01

    The feasibility, practicality, and cost are investigated for establishing a national system or grid of artificial landmarks suitable for automated (near real time) recognition in the multispectral scanner imagery data from an earth observation satellite (EOS). The intended use of such landmarks, for orbit determination and improved mapping accuracy is reviewed. The desirability of using xenon searchlight landmarks for this purpose is explored theoretically and by means of experimental results obtained with LANDSAT 1 and LANDSAT 2. These results are used, in conjunction with the demonstrated efficiency of an automated detection scheme, to determine the size and cost of a xenon searchlight that would be suitable for an EOS Searchlight Landmark Station (SLS), and to facilitate the development of a conceptual design for an automated and environmentally protected EOS SLS.

  12. Experimental land observing data system feasibility study

    NASA Technical Reports Server (NTRS)

    Buckley, J. L.; Kraiman, H.

    1982-01-01

    An end-to-end data system to support a Shuttle-based Multispectral Linear Array (MLA) mission in the mid-1980's was defined. The experimental Land Observing System (ELOS) is discussed. A ground system that exploits extensive assets from the LANDSAT-D Program to effectively meet the objectives of the ELOS Mission was defined. The goal of 10 meter pixel precision, the variety of data acquisition capabilities, and the use of Shuttle are key to the mission requirements, Ground mission management functions are met through the use of GSFC's Multi-Satellite Operations Control Center (MSOCC). The MLA Image Generation Facility (MIGF) combines major hardware elements from the Applications Development Data System (ADDS) facility and LANDSAT Assessment System (LAS) with a special purpose MLA interface unit. LANDSAT-D image processing techniques, adapted to MLA characteristics, form the basis for the use of existing software and the definition of new software required.

  13. Observational database for studies of nearby universe

    NASA Astrophysics Data System (ADS)

    Kaisina, E. I.; Makarov, D. I.; Karachentsev, I. D.; Kaisin, S. S.

    2012-01-01

    We present the description of a database of galaxies of the Local Volume (LVG), located within 10 Mpc around the Milky Way. It contains more than 800 objects. Based on an analysis of functional capabilities, we used the PostgreSQL DBMS as a management system for our LVG database. Applying semantic modelling methods, we developed a physical ER-model of the database. We describe the developed architecture of the database table structure, and the implemented web-access, available at http://www.sao.ru/lv/lvgdb.

  14. Snorkelling between the stars: submarine methods for astronomical observations.

    NASA Astrophysics Data System (ADS)

    Velasco, S.; Quevedo, E.; Font, J.; Oscoz, A.; López, R. L.; Puga, M.; Rebolo, R.; Hernáandez Brito, J.; Llinas, O.; Marrero Callico, G.; Sarmiento, R.

    2017-03-01

    Trying to reach diffraction-limited astronomical observations from ground-based telescopes is very challenging due to the atmospheric effects contributing to a general blurring of the images. However, astronomy is not the only science facing turbulence problems; obtaining quality images of the undersea world is as ambitious as it is on the sky. One of the solutions contemplated to reach high-resolution images is the use of multiple frames of the same target, known as fusion super-resolution (Quevedo et al. 2015), which is the principle for Lucky Imaging (Velasco et al. 2016). Here we present the successful result of joining efforts between the undersea and the astronomical research done at the Canary Islands.

  15. Alternating Renewal Process Models for Behavioral Observation: Simulation Methods, Software, and Validity Illustrations

    ERIC Educational Resources Information Center

    Pustejovsky, James E.; Runyon, Christopher

    2014-01-01

    Direct observation recording procedures produce reductive summary measurements of an underlying stream of behavior. Previous methodological studies of these recording procedures have employed simulation methods for generating random behavior streams, many of which amount to special cases of a statistical model known as the alternating renewal…

  16. A New Method to Directly Observe Tuberculosis Treatment: Skype Observed Therapy, a Patient-Centered Approach.

    PubMed

    Buchman, Tavora; Cabello, Celina

    Tuberculosis (TB) treatment completion is in part determined by patient's adherence to long-term drug regimens. To best ensure compliance, directly observed therapy (DOT) is considered the standard of practice. Nassau County Department of Health TB Control is responsible for providing DOT to patients with TB. Tuberculosis Control sought to use and evaluate Skype Observed Therapy (SOT) as an alternative to DOT for eligible patients. The evaluation included analysis of patient's acceptance and adherence to drug regimen using SOT. Tuberculosis Control assessed staff efficiency and cost savings for this program. Percentages of SOT of patients and successful SOT visits, mileage, and travel time savings. Twenty percent of the caseload used SOT and 100% of patients who were eligible opted in. Average SOT success was 79%. Total mileage savings and time saved were $9,929.07 and 614 hours. Because SOT saves cost and time and is a suitable alternative to DOT for patients, it should be considered as part of new policies and practices in TB control programs.

  17. The Electronically Activated Recorder (EAR): A Method for the Naturalistic Observation of Daily Social Behavior

    PubMed Central

    Mehl, Matthias R.

    2016-01-01

    This article reviews the Electronically Activated Recorder or EAR as an ambulatory ecological momentary assessment tool for the real-world observation of daily behavior. Technically, the EAR is an audio recorder that intermittently records snippets of ambient sounds while participants go about their lives. Conceptually, it is a naturalistic observation method that yields an acoustic log of a person’s day as it unfolds. The power of the EAR lies in unobtrusively collecting authentic real-life observational data. In preserving a high degree of naturalism at the level of the raw recordings, it resembles ethnographic methods; through its sampling and coding, it enables larger empirical studies. The article provides an overview of the EAR method, reviews its validity, utility, and limitations, and discusses it in the context of current developments in ambulatory assessment, specifically the emerging field of mobile sensing. PMID:28529411

  18. The Electronically Activated Recorder (EAR): A Method for the Naturalistic Observation of Daily Social Behavior.

    PubMed

    Mehl, Matthias R

    2017-04-01

    This article reviews the Electronically Activated Recorder or EAR as an ambulatory ecological momentary assessment tool for the real-world observation of daily behavior. Technically, the EAR is an audio recorder that intermittently records snippets of ambient sounds while participants go about their lives. Conceptually, it is a naturalistic observation method that yields an acoustic log of a person's day as it unfolds. The power of the EAR lies in unobtrusively collecting authentic real-life observational data. In preserving a high degree of naturalism at the level of the raw recordings, it resembles ethnographic methods; through its sampling and coding, it enables larger empirical studies. The article provides an overview of the EAR method, reviews its validity, utility, and limitations, and discusses it in the context of current developments in ambulatory assessment, specifically the emerging field of mobile sensing.

  19. What Is Popular Music Studies? Some Observations

    ERIC Educational Resources Information Center

    Cloonan, Martin

    2005-01-01

    Popular Music Studies (PMS) is now taught in over 20 higher education institutions (HEIs) in the UK and numerous others across the world. This article outlines the constituent parts of PMS in the UK and questions its status as a discipline in its own right. It concludes by arguing that, having established itself, PMS will need to deal with two key…

  20. How Many Classroom Observations Are Sufficient? Empirical Findings in the Context of a Longitudinal Study

    ERIC Educational Resources Information Center

    Shih, Jeffrey C.; Ing, Marsha; Tarr, James E.

    2013-01-01

    One method to investigate classroom quality is for a person to observe what is happening in the classroom. However, this method raises practical and technical concerns such as how many observations to collect, when to collect these observations and who should collect these observations. The purpose of this study is to provide empirical evidence to…

  1. Structural equation modeling for observational studies

    USGS Publications Warehouse

    Grace, J.B.

    2008-01-01

    Structural equation modeling (SEM) represents a framework for developing and evaluating complex hypotheses about systems. This method of data analysis differs from conventional univariate and multivariate approaches familiar to most biologists in several ways. First, SEMs are multiequational and capable of representing a wide array of complex hypotheses about how system components interrelate. Second, models are typically developed based on theoretical knowledge and designed to represent competing hypotheses about the processes responsible for data structure. Third, SEM is conceptually based on the analysis of covariance relations. Most commonly, solutions are obtained using maximum-likelihood solution procedures, although a variety of solution procedures are used, including Bayesian estimation. Numerous extensions give SEM a very high degree of flexibility in dealing with nonnormal data, categorical responses, latent variables, hierarchical structure, multigroup comparisons, nonlinearities, and other complicating factors. Structural equation modeling allows researchers to address a variety of questions about systems, such as how different processes work in concert, how the influences of perturbations cascade through systems, and about the relative importance of different influences. I present 2 example applications of SEM, one involving interactions among lynx (Lynx pardinus), mongooses (Herpestes ichneumon), and rabbits (Oryctolagus cuniculus), and the second involving anuran species richness. Many wildlife ecologists may find SEM useful for understanding how populations function within their environments. Along with the capability of the methodology comes a need for care in the proper application of SEM.

  2. Carbon Dioxide Observational Platform System (CO-OPS), feasibility study

    NASA Technical Reports Server (NTRS)

    Bouquet, D. L.; Hall, D. W.; Mcelveen, R. P.

    1987-01-01

    The Carbon Dioxide Observational Platform System (CO-OPS) is a near-space, geostationary, multi-user, unmanned microwave powered monitoring platform system. This systems engineering feasibility study addressed identified existing requirements such as: carbon dioxide observational data requirements, communications requirements, and eye-in-the-sky requirements of other groups like the Defense Department, the Forestry Service, and the Coast Guard. In addition, potential applications in: earth system science, space system sciences, and test and verification (satellite sensors and data management techniques) were considered. The eleven month effort is summarized. Past work and methods of gathering the required observational data were assessed and rough-order-of magnitude cost estimates have shown the CO-OPS system to be most cost effective (less than $30 million within a 10 year lifetime). It was also concluded that there are no technical, schedule, or obstacles that would prevent achieving the objectives of the total 5-year CO-OPS program.

  3. Assessing treatment effects in older breast cancer patients: systematic review of observational research methods.

    PubMed

    de Glas, N A; Kiderlen, M; de Craen, A J M; Hamaker, M E; Portielje, J E A; van de Velde, C J H; Liefers, G J; Bastiaannet, E

    2015-03-01

    Solid evidence of treatment effects in older women with breast cancer is lacking, as they are generally underrepresented in randomized clinical trials on which guideline recommendations are based. An alternative way to study treatment effects in older patients could be to use data from observational studies. However, using appropriate methods in analyzing observational data is a key condition in order to draw valid conclusions, as directly comparing treatments generally results in biased estimates due to confounding by indication. The aim of this systematic review was to investigate the methods that have been used in observational studies that assessed the effects of breast cancer treatment on survival, breast cancer survival and recurrence in older patients (aged 65 years and older). Studies were identified through systematic review of the literature published between January 1st 2009 and December 13th 2013 in the PubMed database and EMBASe. Finally, 31 studies fulfilled the inclusion criteria. Of these, 22 studies directly compared two treatments. Fifteen out of these 22 studies addressed the problem of confounding by indication, while seven studies did not. Nine studies used some form of instrumental variable analysis. In conclusion, the vast majority of observational studies that investigate treatment effects in older breast cancer patients compared treatments directly. These studies are therefore likely to be biased. Observational research will be essential to improve treatment and outcome of older breast cancer patients, but the use of accurate methods is essential to draw valid conclusions from this type of data. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. A method for observing young children's make-believe play

    Treesearch

    Anne Robertson

    1977-01-01

    The influence of toy "realisticness" on the make-believe play of 20- and 26-month old boys and girls was studied by recording their play behaviors when they were presented with specific toys and play suggestions. Results indicate that age changes in make-believe play with the less realistic toys reflect increased competence in symbolic transformation, whereas...

  5. An observational study of defensible space in the neighbourhood park

    NASA Astrophysics Data System (ADS)

    Marzukhi, M. A.; Afiq, M. A.; Zaki, S. Ahmad; Ling, O. H. L.

    2018-02-01

    The planning of neighborhood park is important to provide space for interaction, leisure, and recreation among residents in any neighbourhood area. However, on an almost daily basis, newspapers report inappropriate incidents such as snatch theft, robbery and street attack that occurred in the neighborhood park. These cases reflect the significance of physical planning and design of neighborhood park that directly affect the safety and comfort of the users. Thus, this study attempts to engage with the defensible space concept in ensuring the security elements be applied in the planning of the recreational area. This study adopts a qualitative method form of research that is retrofitted to an observational study. The observational study is significant for revealing the condition of a neighbourhood park in the ‘real-world,’ in which direct observation is conducted on Taman Tasik Puchong Perdana. The observer focused on four elements or variables of defensible space concept including the provision of facilities in the neighborhood park, territoriality, surveillance, image and milieu. The findings revealed that the planning of Taman Tasik Puchong Perdana does not deliberate the defensible space elements, which may contribute to the crime activities in the park. In these circumstances, the planning of neighbourhood park needs to include proposals for the implementation of defensible space in response to the challenges underpinned by crime problems. Besides, the awareness among the residents needs to be emphasized with the support from local authorities and other organizations to manage and sustain the safety environment in the neighborhood park.

  6. Influences on the use of observational methods by practitioners when identifying risk factors in physical work.

    PubMed

    Diego-Mas, Jose-Antonio; Poveda-Bautista, Rocio; Garzon-Leal, Diana-Carolina

    2015-01-01

    Most observational methods for musculoskeletal disorder risk assessment have been developed by researchers to be applied in specific situations, and practitioners could find difficulties in their use in real-work conditions. The main objective of this study was to identify the factors which have an influence on how useful the observational techniques are perceived to be by practitioners and to what extent these factors influence their perception. A survey was conducted on practitioners regarding the problems normally encountered when implementing these methods, as well as the perceived overall utility of these techniques. The results show that practitioners place particular importance on the support the methods provide in making decisions regarding changes in work systems and how applicable they are to different types of jobs. The results of this study can serve as guide to researchers for the development of new assessment techniques that are more useful and applicable in real-work situations.

  7. Observational study of children with aerophagia.

    PubMed

    Loening-Baucke, Vera; Swidsinski, Alexander

    2008-09-01

    Aerophagia is a rare disorder in children. The diagnosis is often delayed, especially when it occurs concomitantly with constipation. The aim of this report is to increase awareness about aerophagia. This study describes 2 girls and 7 boys, 2 to 10.4 years of age, with functional constipation and gaseous abdominal distention. The abdomen was visibly distended, nontender, and tympanitic in all. Documenting less distention on awakening helped to make the diagnosis. Air swallowing, belching, and flatulence were infrequently reported. The rectal examination often revealed a dilated rectal ampulla filled with gas or stool and gas. The abdominal X-ray showed gaseous distention of the colon in all and of the stomach and small bowel in 8 children. Treatment consisted of educating parents and children about air sucking and swallowing, encouraging the children to stop the excessive air swallowing, and suggesting to them not to use drinking straws and not to drink carbonated beverages. The aerophagia resolved in all in 2 to 20 months (mean=8 months).

  8. A novel method for correcting scanline-observational bias of discontinuity orientation

    PubMed Central

    Huang, Lei; Tang, Huiming; Tan, Qinwen; Wang, Dingjian; Wang, Liangqing; Ez Eldin, Mutasim A. M.; Li, Changdong; Wu, Qiong

    2016-01-01

    Scanline observation is known to introduce an angular bias into the probability distribution of orientation in three-dimensional space. In this paper, numerical solutions expressing the functional relationship between the scanline-observational distribution (in one-dimensional space) and the inherent distribution (in three-dimensional space) are derived using probability theory and calculus under the independence hypothesis of dip direction and dip angle. Based on these solutions, a novel method for obtaining the inherent distribution (also for correcting the bias) is proposed, an approach which includes two procedures: 1) Correcting the cumulative probabilities of orientation according to the solutions, and 2) Determining the distribution of the corrected orientations using approximation methods such as the one-sample Kolmogorov-Smirnov test. The inherent distribution corrected by the proposed method can be used for discrete fracture network (DFN) modelling, which is applied to such areas as rockmass stability evaluation, rockmass permeability analysis, rockmass quality calculation and other related fields. To maximize the correction capacity of the proposed method, the observed sample size is suggested through effectiveness tests for different distribution types, dispersions and sample sizes. The performance of the proposed method and the comparison of its correction capacity with existing methods are illustrated with two case studies. PMID:26961249

  9. Assessment of forward head posture in females: observational and photogrammetry methods.

    PubMed

    Salahzadeh, Zahra; Maroufi, Nader; Ahmadi, Amir; Behtash, Hamid; Razmjoo, Arash; Gohari, Mahmoud; Parnianpour, Mohamad

    2014-01-01

    There are different methods to assess forward head posture (FHP) but the accuracy and discrimination ability of these methods are not clear. Here, we want to compare three postural angles for FHP assessment and also study the discrimination accuracy of three photogrammetric methods to differentiate groups categorized based on observational method. All Seventy-eight healthy female participants (23 ± 2.63 years), were classified into three groups: moderate-severe FHP, slight FHP and non FHP based on observational postural assessment rules. Applying three photogrammetric methods - craniovertebral angle, head title angle and head position angle - to measure FHP objectively. One - way ANOVA test showed a significant difference in three categorized group's craniovertebral angle (P< 0.05, F=83.07). There was no dramatic difference in head tilt angle and head position angle methods in three groups. According to Linear Discriminate Analysis (LDA) results, the canonical discriminant function (Wilks'Lambda) was 0.311 for craniovertebral angle with 79.5% of cross-validated grouped cases correctly classified. Our results showed that, craniovertebral angle method may discriminate the females with moderate-severe and non FHP more accurate than head position angle and head tilt angle. The photogrammetric method had excellent inter and intra rater reliability to assess the head and cervical posture.

  10. Comparing methods for estimation of heterogeneous treatment effects using observational data from health care databases.

    PubMed

    Wendling, T; Jung, K; Callahan, A; Schuler, A; Shah, N H; Gallego, B

    2018-06-03

    There is growing interest in using routinely collected data from health care databases to study the safety and effectiveness of therapies in "real-world" conditions, as it can provide complementary evidence to that of randomized controlled trials. Causal inference from health care databases is challenging because the data are typically noisy, high dimensional, and most importantly, observational. It requires methods that can estimate heterogeneous treatment effects while controlling for confounding in high dimensions. Bayesian additive regression trees, causal forests, causal boosting, and causal multivariate adaptive regression splines are off-the-shelf methods that have shown good performance for estimation of heterogeneous treatment effects in observational studies of continuous outcomes. However, it is not clear how these methods would perform in health care database studies where outcomes are often binary and rare and data structures are complex. In this study, we evaluate these methods in simulation studies that recapitulate key characteristics of comparative effectiveness studies. We focus on the conditional average effect of a binary treatment on a binary outcome using the conditional risk difference as an estimand. To emulate health care database studies, we propose a simulation design where real covariate and treatment assignment data are used and only outcomes are simulated based on nonparametric models of the real outcomes. We apply this design to 4 published observational studies that used records from 2 major health care databases in the United States. Our results suggest that Bayesian additive regression trees and causal boosting consistently provide low bias in conditional risk difference estimates in the context of health care database studies. Copyright © 2018 John Wiley & Sons, Ltd.

  11. Linking Indigenous Knowledge and Observed Climate Change Studies

    NASA Technical Reports Server (NTRS)

    Alexander, Chief Clarence; Bynum, Nora; Johnson, Liz; King, Ursula; Mustonen, Tero; Neofotis, Peter; Oettle, Noel; Rosenzweig, Cynthia; Sakakibara, Chie; Shadrin, Chief Vyacheslav; hide

    2010-01-01

    We present indigenous knowledge narratives and explore their connections to documented temperature and other climate changes and observed climate change impact studies. We then propose a framework for enhancing integration of these indigenous narratives of observed climate change with global assessments. Our aim is to contribute to the thoughtful and respectful integration of indigenous knowledge with scientific data and analysis, so that this rich body of knowledge can inform science, and so that indigenous and traditional peoples can use the tools and methods of science for the benefit of their communities if they choose to do so. Enhancing ways of understanding such connections are critical as the Intergovernmental Panel on Climate Change Fifth Assessment process gets underway.

  12. Observation

    ERIC Educational Resources Information Center

    Helfrich, Shannon

    2016-01-01

    Helfrich addresses two perspectives from which to think about observation in the classroom: that of the teacher observing her classroom, her group, and its needs, and that of the outside observer coming into the classroom. Offering advice from her own experience, she encourages and defends both. Do not be afraid of the disruption of outside…

  13. Observations

    ERIC Educational Resources Information Center

    Joosten, Albert Max

    2016-01-01

    Joosten begins his article by telling us that love and knowledge together are the foundation for our work with children. This combination is at the heart of our observation. With this as the foundation, he goes on to offer practical advice to aid our practice of observation. He offers a "List of Objects of Observation" to help guide our…

  14. Pedagogical strategies used in clinical medical education: an observational study

    PubMed Central

    2010-01-01

    Background Clinical teaching is a complex learning situation influenced by the learning content, the setting and the participants' actions and interactions. Few empirical studies have been conducted in order to explore how clinical supervision is carried out in authentic situations. In this study we explore how clinical teaching is carried out in a clinical environment with medical students. Methods Following an ethnographic approach looking for meaning patterns, similarities and differences in how clinical teachers manage clinical teaching; non-participant observations and informal interviews were conducted during a four month period 2004-2005. The setting was at a teaching hospital in Sweden. The participants were clinical teachers and their 4th year medical students taking a course in surgery. The observations were guided by the aim of the study. Observational notes and notes from informal interviews were transcribed after each observation and all data material was analysed qualitatively. Results Seven pedagogical strategies were found to be applied, namely: 1) Questions and answers, 2) Lecturing, 3) Piloting, 4) Prompting, 5) Supplementing, 6) Demonstrating, and 7) Intervening. Conclusions This study contributes to previous research in describing a repertoire of pedagogical strategies used in clinical education. The findings showed that three superordinate qualitatively different ways of teaching could be identified that fit Ramsden's model. Each of these pedagogical strategies encompass different focus in teaching; either a focus on the teacher's knowledge and behaviour or the student's behaviour and understanding. We suggest that an increased awareness of the strategies in use will increase clinical teachers' teaching skills and the consequences they will have on the students' ability to learn. The pedagogical strategies need to be considered and scrutinized in further research in order to verify their impact on students' learning. PMID:20105340

  15. 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).

  16. A new method for quantifying and modeling large scale surface water inundation dynamics and key drivers using multiple time series of Earth observation and river flow data. A case study for Australia's Murray-Darling Basin

    NASA Astrophysics Data System (ADS)

    Heimhuber, Valentin; Tulbure, Mirela G.; Broich, Mark

    2017-04-01

    -floodplain areas (r-squared > 0.24), which were primarily driven by local rainfall. Our results indicate that local climate conditions (i.e. P, ET, SM) had more influence on SW dynamics in the northern compared to the southern MDB and were the most influential in the least regulated and most extended floodplains in the north-west. We also applied the statistical models of two floodplain areas with contrasting flooding regimes to predict SW extents of cloud-affected time steps in the Landsat time series during the large 2010 floods with high validated accuracy (r-squared > 0.97). Our findings illustrate that integrating multi-decadal time series of Earth observation data and in situ measurements with statistical modeling techniques can provide cost-effective tools for improving the management of limited SW resources and floods. The data-driven method is applicable to other large river basins and provides statistical models that can predict SW extent for cloud-affected Landsat observations or during the peak of floods and hence, allows a more detailed quantification of the dynamics of large floods compared to existing approaches. Future research will investigate the potential of image fusion techniques (i.e. ESTARFM) for improving the quantification of rapid changes in SW distribution by combining MODIS and Landsat imagery.

  17. Observation

    ERIC Educational Resources Information Center

    Patell, Hilla

    2016-01-01

    In order to achieve the goal of observation, preparation of the adult, the observer, is necessary. This preparation, says Hilla Patell, requires us to "have an appreciation of the significance of the child's spontaneous activities and a more thorough understanding of the child's needs." She discusses the growth of both the desire to…

  18. Observation

    ERIC Educational Resources Information Center

    Kripalani, Lakshmi A.

    2016-01-01

    The adult who is inexperienced in the art of observation may, even with the best intentions, react to a child's behavior in a way that hinders instead of helping the child's development. Kripalani outlines the need for training and practice in observation in order to "understand the needs of the children and...to understand how to remove…

  19. Rainfall Observed Over Bangladesh 2000-2008: A Comparison of Spatial Interpolation Methods

    NASA Astrophysics Data System (ADS)

    Pervez, M.; Henebry, G. M.

    2010-12-01

    In preparation for a hydrometeorological study of freshwater resources in the greater Ganges-Brahmaputra region, we compared the results of four methods of spatial interpolation applied to point measurements of daily rainfall over Bangladesh during a seven year period (2000-2008). Two univariate (inverse distance weighted and spline-regularized and tension) and two multivariate geostatistical (ordinary kriging and kriging with external drift) methods were used to interpolate daily observations from a network of 221 rain gauges across Bangladesh spanning an area of 143,000 sq km. Elevation and topographic index were used as the covariates in the geostatistical methods. The validity of the interpolated maps was analyzed through cross-validation. The quality of the methods was assessed through the Pearson and Spearman correlations and root mean square error measurements of accuracy in cross-validation. Preliminary results indicated that the univariate methods performed better than the geostatistical methods at daily scales, likely due to the relatively dense sampled point measurements and a weak correlation between the rainfall and covariates at daily scales in this region. Inverse distance weighted produced the better results than the spline. For the days with extreme or high rainfall—spatially and quantitatively—the correlation between observed and interpolated estimates appeared to be high (r2 ~ 0.6 RMSE ~ 10mm), although for low rainfall days the correlations were poor (r2 ~ 0.1 RMSE ~ 3mm). The performance quality of these methods was influenced by the density of the sample point measurements, the quantity of the observed rainfall along with spatial extent, and an appropriate search radius defining the neighboring points. Results indicated that interpolated rainfall estimates at daily scales may introduce uncertainties in the successive hydrometeorological analysis. Interpolations at 5-day, 10-day, 15-day, and monthly time scales are currently under

  20. Observation of autoionization in O 2 by an electron-electron coincidence method

    NASA Astrophysics Data System (ADS)

    Doering, J. P.; Yang, J.; Cooper, J. W.

    1995-01-01

    A strong transition to an autoionizing stata has been observed in O 2 at 16.83 ± 0.11 eV by means of a new electron-electron conincidence method. The method uses the fact that electrons arising from autoionizing states appear at a constant energy loss corresponding to the excitation energy of the autoionizing state rather than at a constant ionization potential as do electrons produced by direct ionization. Comparison of the present data with previous photoionization studies suggests that the autoionizing O 2 state is the same state deduced to be responsible for abnormal vibrational intensities in the O 2+X 2Πg ground state when 16.85 eV Ne(I) photons are used. These electron-electron coincidence experiments provide a direct new method for the study of autoionization produced by electron impact.

  1. Evaluation of methods to derive green-up dates based on daily NDVI satellite observations

    NASA Astrophysics Data System (ADS)

    Doktor, Daniel

    2010-05-01

    Bridging the gap between satellite derived green-up dates and in situ phenological observations has been the purpose of many studies over the last decades. Despite substantial advancements in satellite technology and data quality checks there is as yet no universally accepted method for extracting phenological metrics based on satellite derived vegetation indices. Dependent on the respective method derived green-up dates can vary up to serveral weeks using identical data sets. Consequently, it is difficult to compare various studies and to accurately determine an increased vegetation length due to changing temperature patterns as observed by ground phenological networks. Here, I compared how the characteristic NDVI increase over temperate deciduous forests in Germany in spring relates to respective budburst events observed on the ground. MODIS Terra daily surface reflectances with a 250 m resolution (2000-2008) were gathered to compute daily NDVI values. As ground truth, observations of the extensive phenological network of the German Weather Service were used. About 1500 observations per year and species (Beech, Oak and Birch) were available evenly distributed all over Germany. Two filtering methods were tested to reduce the noisy raw data. The first method only keeps NDVI values which are classified as ‚ideal global quality' and applies on those a temporal moving window where values are removed which differ more than 20% of the mean. The second method uses an adaptation of the BISE (Best Index Slope Extraction) algorithm. Subsequently, three functions were fitted to the selected observations: a simple linear interpolation, a sigmoidal function and a double logistic sigmoidal function allowing to approximate two temporally separated green-up signals. The green-up date was then determined at halfway between minimum and maximum (linear interpolation) or at the inflexion point of the sigmoidal curve. A number of global threshold values (NDVI 0.4,0.5,0.6) and

  2. How safe do teenagers behave on Facebook? An observational study.

    PubMed

    Vanderhoven, Ellen; Schellens, Tammy; Valcke, Martin; Raes, Annelies

    2014-01-01

    The substantial use of social network sites by teenagers has raised concerns about privacy and security. Previous research about behavior on social network sites was mostly based on surveys and interviews. Observational research overcomes problems inherent to this research method, for example social desirability. However, existing observational research mostly focuses on public profiles of young adults. Therefore, the current observation-study includes 1050 public and non-public Facebook-profiles of teenagers (13-18) to investigate (1) what kind of information teenagers post on their profile, (2) to what extent they protect this information using privacy-settings and (3) how much risky information they have on their profile. It was found that young people mostly post pictures, interests and some basic personal information on their profile. Some of them manage their privacy-settings as such that this information is reserved for friends' eyes only, but a lot of information is accessible on the friends-of-friends' pages. Although general risk scores are rather low, more detailed analyses show that teenagers nevertheless post a significant amount of risky information. Moreover, older teenagers and girls post more (risky) information while there are no differences in applying privacy settings. We found no differences in the Facebook behavior of teenagers enrolled in different education forms. Implications of these results are discussed.

  3. How Safe Do Teenagers Behave on Facebook? An Observational Study

    PubMed Central

    Vanderhoven, Ellen; Schellens, Tammy; Valcke, Martin; Raes, Annelies

    2014-01-01

    The substantial use of social network sites by teenagers has raised concerns about privacy and security. Previous research about behavior on social network sites was mostly based on surveys and interviews. Observational research overcomes problems inherent to this research method, for example social desirability. However, existing observational research mostly focuses on public profiles of young adults. Therefore, the current observation-study includes 1050 public and non-public Facebook-profiles of teenagers (13–18) to investigate (1) what kind of information teenagers post on their profile, (2) to what extent they protect this information using privacy-settings and (3) how much risky information they have on their profile. It was found that young people mostly post pictures, interests and some basic personal information on their profile. Some of them manage their privacy-settings as such that this information is reserved for friends' eyes only, but a lot of information is accessible on the friends-of-friends' pages. Although general risk scores are rather low, more detailed analyses show that teenagers nevertheless post a significant amount of risky information. Moreover, older teenagers and girls post more (risky) information while there are no differences in applying privacy settings. We found no differences in the Facebook behavior of teenagers enrolled in different education forms. Implications of these results are discussed. PMID:25162234

  4. Palliative care team visits. Qualitative study through participant observation

    PubMed Central

    Bueno Pernias, Maria José; Hueso Montoro, César; Guardia Mancilla, Plácido; Montoya Juárez, Rafael; García Caro, Maria Paz

    2016-01-01

    Objectives: To describe the clinical encounters that occur when a palliative care team provides patient care and the features that influence these encounters and indicate whether they are favorable or unfavorable depending on the expectations and feelings of the various participants. Methods: A qualitative case study conducted via participant observation. A total of 12 observations of the meetings of palliative care teams with patients and families in different settings (home, hospital and consultation room) were performed. The visits were follow-up or first visits, either scheduled or on demand. Content analysis of the observation was performed. Results: The analysis showed the normal follow-up activity of the palliative care unit that was focused on controlling symptoms, sharing information and providing advice on therapeutic regimens and care. The environment appeared to condition the patients' expressions and the type of patient relationship. Favorable clinical encounter conditions included kindness and gratitude. Unfavorable conditions were deterioration caused by approaching death, unrealistic family objectives and limited resources. Conclusion: Home visits from basic palliative care teams play an important role in patient and family well-being. The visits seem to focus on controlling symptoms and are conditioned by available resources. PMID:27226663

  5. Infants' social withdrawal symptoms assessed with a direct infant observation method in primary health care.

    PubMed

    Puura, Kaija; Mäntymaa, Mirjami; Luoma, Ilona; Kaukonen, Pälvi; Guedeney, Antoine; Salmelin, Raili; Tamminen, Tuula

    2010-12-01

    Distressed infants may withdraw from social interaction, but recognising infants' social withdrawal is difficult. The aims of the study were to see whether an infant observation method can be reliably used by front line workers, and to examine the prevalence of infants' social withdrawal symptoms. A random sample of 363 families with four, eight or 18-month-old infants participated in the study. The infants were examined by general practitioners (GPs) in well-baby clinics with the Alarm Distress BaBy Scale (ADBB), an observation method developed for clinical settings. A score of five or more on the ADBB Scale in two subsequent assessments at a two-week interval was regarded as a sign of clinically significant infant social withdrawal. Kappas were calculated for the GPs' correct rating of withdrawn/not withdrawn against a set of videotapes rated by developer of the method, Professor Guedeney and his research group. The kappas for their ratings ranged from 0.5 to 1. The frequency of infants scoring above the cut off in two subsequent assessments was 3%. The ADBB Scale is a promising method for detecting infant social withdrawal in front line services. Three percents of infants were showing sustained social withdrawal as a sign of distress in this normal population sample. Copyright © 2010 Elsevier Inc. All rights reserved.

  6. Design of a practical model-observer-based image quality assessment method for CT imaging systems

    NASA Astrophysics Data System (ADS)

    Tseng, Hsin-Wu; Fan, Jiahua; Cao, Guangzhi; Kupinski, Matthew A.; Sainath, Paavana

    2014-03-01

    The channelized Hotelling observer (CHO) is a powerful method for quantitative image quality evaluations of CT systems and their image reconstruction algorithms. It has recently been used to validate the dose reduction capability of iterative image-reconstruction algorithms implemented on CT imaging systems. The use of the CHO for routine and frequent system evaluations is desirable both for quality assurance evaluations as well as further system optimizations. The use of channels substantially reduces the amount of data required to achieve accurate estimates of observer performance. However, the number of scans required is still large even with the use of channels. This work explores different data reduction schemes and designs a new approach that requires only a few CT scans of a phantom. For this work, the leave-one-out likelihood (LOOL) method developed by Hoffbeck and Landgrebe is studied as an efficient method of estimating the covariance matrices needed to compute CHO performance. Three different kinds of approaches are included in the study: a conventional CHO estimation technique with a large sample size, a conventional technique with fewer samples, and the new LOOL-based approach with fewer samples. The mean value and standard deviation of area under ROC curve (AUC) is estimated by shuffle method. Both simulation and real data results indicate that an 80% data reduction can be achieved without loss of accuracy. This data reduction makes the proposed approach a practical tool for routine CT system assessment.

  7. Methods of Teaching Reading to EFL Learners: A Case Study

    ERIC Educational Resources Information Center

    Sanjaya, Dedi; Rahmah; Sinulingga, Johan; Lubis, Azhar Aziz; Yusuf, Muhammad

    2014-01-01

    Methods of teaching reading skill are not the same in different countries. It depends on the condition and situation of the learners. Observing the method of teaching in Malaysia was the purpose of this study and the result of the study shows that there are 5 methods that are applied in classroom activities namely Grammar Translation Method (GTM),…

  8. Simple tool for the rapid, automated quantification of glacier advance/retreat observations using multiple methods

    NASA Astrophysics Data System (ADS)

    Lea, J.

    2017-12-01

    The quantification of glacier change is a key variable within glacier monitoring, with the method used potentially being crucial to ensuring that data can be appropriately compared with environmental data. The topic and timescales of study (e.g. land/marine terminating environments; sub-annual/decadal/centennial/millennial timescales) often mean that different methods are more suitable for different problems. However, depending on the GIS/coding expertise of the user, some methods can potentially be time consuming to undertake, making large-scale studies problematic. In addition, examples exist where different users have nominally applied the same methods in different studies, though with minor methodological inconsistencies in their approach. In turn, this will have implications for data homogeneity where regional/global datasets may be constructed. Here, I present a simple toolbox scripted in a Matlab® environment that requires only glacier margin and glacier centreline data to quantify glacier length, glacier change between observations, rate of change, in addition to other metrics. The toolbox includes the option to apply the established centreline or curvilinear box methods, or a new method: the variable box method - designed for tidewater margins where box width is defined as the total width of the individual terminus observation. The toolbox is extremely flexible, and has the option to be applied as either Matlab® functions within user scripts, or via a graphical user interface (GUI) for those unfamiliar with a coding environment. In both instances, there is potential to apply the methods quickly to large datasets (100s-1000s of glaciers, with potentially similar numbers of observations each), thus ensuring large scale methodological consistency (and therefore data homogeneity) and allowing regional/global scale analyses to be achievable for those with limited GIS/coding experience. The toolbox has been evaluated against idealised scenarios demonstrating

  9. Indirect Observation in Everyday Contexts: Concepts and Methodological Guidelines within a Mixed Methods Framework.

    PubMed

    Anguera, M Teresa; Portell, Mariona; Chacón-Moscoso, Salvador; Sanduvete-Chaves, Susana

    2018-01-01

    Indirect observation is a recent concept in systematic observation. It largely involves analyzing textual material generated either indirectly from transcriptions of audio recordings of verbal behavior in natural settings (e.g., conversation, group discussions) or directly from narratives (e.g., letters of complaint, tweets, forum posts). It may also feature seemingly unobtrusive objects that can provide relevant insights into daily routines. All these materials constitute an extremely rich source of information for studying everyday life, and they are continuously growing with the burgeoning of new technologies for data recording, dissemination, and storage. Narratives are an excellent vehicle for studying everyday life, and quantitization is proposed as a means of integrating qualitative and quantitative elements. However, this analysis requires a structured system that enables researchers to analyze varying forms and sources of information objectively. In this paper, we present a methodological framework detailing the steps and decisions required to quantitatively analyze a set of data that was originally qualitative. We provide guidelines on study dimensions, text segmentation criteria, ad hoc observation instruments, data quality controls, and coding and preparation of text for quantitative analysis. The quality control stage is essential to ensure that the code matrices generated from the qualitative data are reliable. We provide examples of how an indirect observation study can produce data for quantitative analysis and also describe the different software tools available for the various stages of the process. The proposed method is framed within a specific mixed methods approach that involves collecting qualitative data and subsequently transforming these into matrices of codes (not frequencies) for quantitative analysis to detect underlying structures and behavioral patterns. The data collection and quality control procedures fully meet the requirement of

  10. Indirect Observation in Everyday Contexts: Concepts and Methodological Guidelines within a Mixed Methods Framework

    PubMed Central

    Anguera, M. Teresa; Portell, Mariona; Chacón-Moscoso, Salvador; Sanduvete-Chaves, Susana

    2018-01-01

    Indirect observation is a recent concept in systematic observation. It largely involves analyzing textual material generated either indirectly from transcriptions of audio recordings of verbal behavior in natural settings (e.g., conversation, group discussions) or directly from narratives (e.g., letters of complaint, tweets, forum posts). It may also feature seemingly unobtrusive objects that can provide relevant insights into daily routines. All these materials constitute an extremely rich source of information for studying everyday life, and they are continuously growing with the burgeoning of new technologies for data recording, dissemination, and storage. Narratives are an excellent vehicle for studying everyday life, and quantitization is proposed as a means of integrating qualitative and quantitative elements. However, this analysis requires a structured system that enables researchers to analyze varying forms and sources of information objectively. In this paper, we present a methodological framework detailing the steps and decisions required to quantitatively analyze a set of data that was originally qualitative. We provide guidelines on study dimensions, text segmentation criteria, ad hoc observation instruments, data quality controls, and coding and preparation of text for quantitative analysis. The quality control stage is essential to ensure that the code matrices generated from the qualitative data are reliable. We provide examples of how an indirect observation study can produce data for quantitative analysis and also describe the different software tools available for the various stages of the process. The proposed method is framed within a specific mixed methods approach that involves collecting qualitative data and subsequently transforming these into matrices of codes (not frequencies) for quantitative analysis to detect underlying structures and behavioral patterns. The data collection and quality control procedures fully meet the requirement of

  11. Squeezing observational data for better causal inference: Methods and examples for prevention research.

    PubMed

    Garcia-Huidobro, Diego; Michael Oakes, J

    2017-04-01

    Randomised controlled trials (RCTs) are typically viewed as the gold standard for causal inference. This is because effects of interest can be identified with the fewest assumptions, especially imbalance in background characteristics. Yet because conducting RCTs are expensive, time consuming and sometimes unethical, observational studies are frequently used to study causal associations. In these studies, imbalance, or confounding, is usually controlled with multiple regression, which entails strong assumptions. The purpose of this manuscript is to describe strengths and weaknesses of several methods to control for confounding in observational studies, and to demonstrate their use in cross-sectional dataset that use patient registration data from the Juan Pablo II Primary Care Clinic in La Pintana-Chile. The dataset contains responses from 5855 families who provided complete information on family socio-demographics, family functioning and health problems among their family members. We employ regression adjustment, stratification, restriction, matching, propensity score matching, standardisation and inverse probability weighting to illustrate the approaches to better causal inference in non-experimental data and compare results. By applying study design and data analysis techniques that control for confounding in different ways than regression adjustment, researchers may strengthen the scientific relevance of observational studies. © 2016 International Union of Psychological Science.

  12. A double-observer method for reducing bias in faecal pellet surveys of forest ungulates

    USGS Publications Warehouse

    Jenkins, K.J.; Manly, B.F.J.

    2008-01-01

    1. Faecal surveys are used widely to study variations in abundance and distribution of forest-dwelling mammals when direct enumeration is not feasible. The utility of faecal indices of abundance is limited, however, by observational bias and variation in faecal disappearance rates that obscure their relationship to population size. We developed methods to reduce variability in faecal surveys and improve reliability of faecal indices. 2. We used double-observer transect sampling to estimate observational bias of faecal surveys of Roosevelt elk Cervus elaphus roosevelti and Columbian black-tailed deer Odocoileus hemionus columbianus in Olympic National Park, Washington, USA. We also modelled differences in counts of faecal groups obtained from paired cleared and uncleared transect segments as a means to adjust standing crop faecal counts for a standard accumulation interval and to reduce bias resulting from variable decay rates. 3. Estimated detection probabilities of faecal groups ranged from < 0.2-1.0 depending upon the observer, whether the faecal group was from elk or deer, faecal group size, distance of the faecal group from the sampling transect, ground vegetation cover, and the interaction between faecal group size and distance from the transect. 4. Models of plot-clearing effects indicated that standing crop counts of deer faecal groups required 34% reduction on flat terrain and 53% reduction on sloping terrain to represent faeces accumulated over a standard 100-day interval, whereas counts of elk faecal groups required 0% and 46% reductions on flat and sloping terrain, respectively. 5. Synthesis and applications. Double-observer transect sampling provides a cost-effective means of reducing observational bias and variation in faecal decay rates that obscure the interpretation of faecal indices of large mammal abundance. Given the variation we observed in observational bias of faecal surveys and persistence of faeces, we emphasize the need for future

  13. Comparing Simulations and Observations of Galaxy Evolution: Methods for Constraining the Nature of Stellar Feedback

    NASA Astrophysics Data System (ADS)

    Hummels, Cameron

    Computational hydrodynamical simulations are a very useful tool for understanding how galaxies form and evolve over cosmological timescales not easily revealed through observations. However, they are only useful if they reproduce the sorts of galaxies that we see in the real universe. One of the ways in which simulations of this sort tend to fail is in the prescription of stellar feedback, the process by which nascent stars return material and energy to their immediate environments. Careful treatment of this interaction in subgrid models, so-called because they operate on scales below the resolution of the simulation, is crucial for the development of realistic galaxy models. Equally important is developing effective methods for comparing simulation data against observations to ensure galaxy models which mimic reality and inform us about natural phenomena. This thesis examines the formation and evolution of galaxies and the observable characteristics of the resulting systems. We employ extensive use of cosmological hydrodynamical simulations in order to simulate and interpret the evolution of massive spiral galaxies like our own Milky Way. First, we create a method for producing synthetic photometric images of grid-based hydrodynamical models for use in a direct comparison against observations in a variety of filter bands. We apply this method to a simulation of a cluster of galaxies to investigate the nature of the red-sequence/blue-cloud dichotomy in the galaxy color-magnitude diagram. Second, we implement several subgrid models governing the complex behavior of gas and stars on small scales in our galaxy models. Several numerical simulations are conducted with similar initial conditions, where we systematically vary the subgrid models, afterward assessing their efficacy through comparisons of their internal kinematics with observed systems. Third, we generate an additional method to compare observations with simulations, focusing on the tenuous circumgalactic

  14. Evaluation of Multiclass Model Observers in PET LROC Studies

    NASA Astrophysics Data System (ADS)

    Gifford, H. C.; Kinahan, P. E.; Lartizien, C.; King, M. A.

    2007-02-01

    A localization ROC (LROC) study was conducted to evaluate nonprewhitening matched-filter (NPW) and channelized NPW (CNPW) versions of a multiclass model observer as predictors of human tumor-detection performance with PET images. Target localization is explicitly performed by these model observers. Tumors were placed in the liver, lungs, and background soft tissue of a mathematical phantom, and the data simulation modeled a full-3D acquisition mode. Reconstructions were performed with the FORE+AWOSEM algorithm. The LROC study measured observer performance with 2D images consisting of either coronal, sagittal, or transverse views of the same set of cases. Versions of the CNPW observer based on two previously published difference-of-Gaussian channel models demonstrated good quantitative agreement with human observers. One interpretation of these results treats the CNPW observer as a channelized Hotelling observer with implicit internal noise

  15. Using non-specialist observers in 4AFC human observer studies

    NASA Astrophysics Data System (ADS)

    Elangovan, Premkumar; Mackenzie, Alistair; Dance, David R.; Young, Kenneth C.; Wells, Kevin

    2017-03-01

    Virtual clinical trials (VCTs) are an emergent approach for rapid evaluation and comparison of various breast imaging technologies and techniques using computer-based modeling tools. Increasingly 4AFC (Four alternative forced choice) virtual clinical trials are used to compare detection performances of different breast imaging modalities. Most prior studies have used physicists and/or radiologists and physicists interchangeably. However, large scale use of statistically significant 4AFC observer studies is challenged by the individual time commitment and cost of such observers, often drawn from a limited local pool of specialists. This work aims to investigate whether non-specialist observers can be used to supplement such studies. A team of five specialist observers (medical physicists) and five non-specialists participated in a 4AFC study containing simulated 2D-mammography and DBT (digital breast tomosynthesis) images, produced using the OPTIMAM toolbox for VCTs. The images contained 4mm irregular solid masses and 4mm spherical targets at a range of contrast levels embedded in a realistic breast phantom background. There was no statistically significant difference between the detection performance of medical physicists and non-specialists (p>0.05). However, non-specialists took longer to complete the study than their physicist counterparts, which was statistically significant (p<0.05). Overall, the results from both observer groups indicate that DBT has a lower detectable threshold contrast than 2D-mammography for both masses and spheres, and both groups found spheres easier to detect than irregular solid masses.

  16. Study of Rayleigh-Love coupling from Spatial Gradient Observation

    NASA Astrophysics Data System (ADS)

    Lin, C. J.; Hosseini, K.; Donner, S.; Vernon, F.; Wassermann, J. M.; Igel, H.

    2017-12-01

    We present a new method to study Rayleigh-Love coupling. Instead of using seismograms solely, where ground motion is recorded as function of time, we incorporate with rotation and strain, also called spatial gradient where ground is represented as function of distance. Seismic rotation and strain are intrinsic different observable wavefield so are helpful to indentify wave type and wave propagation. A Mw 7.5 earthquake on 29 March 2015 occurred in Kokopo, Papua New Guinea recorded by a dense seismic array at PFO, California are used to obtaint seismic spatial gradient. We firstly estimate time series of azimuthal direction and phase velocity of SH wave and Rayleigh wave by analyzing collocated seismograms and rotations. This result also compares with frequency wavenumber methods using a nearby ANZA seismic array. We find the direction of Rayleigh wave fits well with great-circle back azimuth during wave propagation, while the direction of Love wave deviates from that, especially when main energy of Rayleigh wave arrives. From the analysis of cross-correlation between areal strain and vertical rotation, it reveals that high coherence, either positive or negative, happens at the same time when Love wave deparate from great-circle path. We also find the observed azimuth of Love wave and polarized particle motion of Rayleigh wave fits well with the fast direction of Rayleigh wave, for the period of 50 secs. We conclude the cause of deviated azimuth of Love wave is due to Rayleigh-Love coupling, as surface wave propagates through the area with anisotropic structure.

  17. Developing methods of determining unknown roational periods of asteroids via observations of (3122) Florence by the Harvard Observing Project

    NASA Astrophysics Data System (ADS)

    Abrams, Natasha Sarah; Bieryla, Allyson; Gomez, Sebastian; Huang, Jane; Lewis, John; Todd, Zoe; Alam, Munazza; Carmichael, Theron; Garrison, Lehman H.; Weaver, Ian; Chen, Chen; McGruder, Chima; Medina, Amber

    2018-06-01

    (3122) Florence is an asteroid that made the headlines with its close approach to Earth in late 2017. It is one of the biggest and brightest near-Earth asteroids that has been discovered and it has recently been found to have two moons. By observing the light reflected off an asteroid, we can measure its brightness over time and determine the rotational period of the asteroid. An asteroid’s rotational period can reveal information about its physical characteristics, such as its shape, and further our knowledge about processes that contribute to asteroid rotation in general. The Harvard Observing Project (HOP) is an initiative that allows undergraduates to learn about observational astronomy and take part in formal data collection and analysis. Over the course of the fall 2017 semester, HOP obtained four multi-hour, continuous observations in the R-band of the asteroid using the Harvard University 16-inch Clay Telescope. In our analysis, we reduced the images and performed astrometry and photometry on the data. The asteroid’s light curve was produced using AstroImageJ and we used the Python package gatspy to determine its rotational period. We found the rotational period to be 2.22 hours +/- 0.25, which agrees with the known rotational period of 2.3580 hours +/- 0.0002. This spring 2018 semester we are applying our methods to data collected on asteroids with unknown rotational periods and plan to present our findings.

  18. Informing urban carbon emissions with atmospheric observations: motivation, methods, and reducing uncertainties.

    NASA Astrophysics Data System (ADS)

    Kort, E. A.; Ware, J.; Duren, R. M.; Schimel, D.; Miller, C. E.; Decola, P.

    2014-12-01

    Urban regions play a dominant role in the anthropogenic perturbation to atmospheric carbon dioxide and methane. With increasing urbanization (notably in developing nations) and increasing emissions, quantitative observational information on emissions of CO2 and CH4 becomes critical for improved understanding of the global carbon cycle and for carbon management/policy decisions. In this presentation, we will discuss the impact uncertainty in anthropogenic emissions has on global carbon-climate understanding, providing broad geophysical motivation for urban studies. We will further discuss observations of urban regions at different scales (satellite vs. in-situ), and investigate the information content of these complementary methods for answering targeted questions on both global carbon fluxes and regional management decisions. Finally, we will present new attempts at reducing uncertainty in high-resolution inversions leveraging remotely sensed aerosol profiles to constrain both mixing depths and vertical distributions of trace gases.

  19. The value of earth observations: methods and findings on the value of Landsat imagery

    USGS Publications Warehouse

    Miller, Holly M.; Serbina, Larisa O.; Richardson, Leslie A.; Ryker, Sarah J.; Newman, Timothy R.

    2016-01-01

    Data from Earth observation systems are used extensively in managing and monitoring natural resources, natural hazards, and the impacts of climate change, but the value of such data can be difficult to estimate, particularly when it is available at no cost. Assessing the socioeconomic and scientific value of these data provides a better understanding of the existing and emerging research, science, and applications related to this information and contributes to the decision making process regarding current and future Earth observation systems. Recent USGS research on Landsat data has advanced the literature in this area by using a variety of methods to estimate value. The results of a 2012 survey of Landsat users, a 2013 requirements assessment, and 2013 case studies of applications of Landsat imagery are discussed.

  20. A New Quality Control Method base on IRMCD for Wind Profiler Observation towards Future Assimilation Application

    NASA Astrophysics Data System (ADS)

    Chen, Min; Zhang, Yu

    2017-04-01

    A wind profiler network with a total of 65 profiling radars was operated by the MOC/CMA in China until July 2015. In this study, a quality control procedure is constructed to incorporate the profiler data from the wind-profiling network into the local data assimilation and forecasting system (BJRUC). The procedure applies a blacklisting check that removes stations with gross errors and an outlier check that rejects data with large deviations from the background. Instead of the bi-weighting method, which has been commonly implemented in outlier elimination for one-dimensional scalar observations, an outlier elimination method is developed based on the iterated reweighted minimum covariance determinant (IRMCD) for multi-variate observations such as wind profiler data. A quality control experiment is separately performed for subsets containing profiler data tagged in parallel with/without rain flags at every 00UTC/12UTC from 20 June to 30 Sep 2015. From the results, we find that with the quality control, the frequency distributions of the differences between the observations and model background become more Gaussian-like and meet the requirements of a Gaussian distribution for data assimilation. Further intensive assessment for each quality control step reveals that the stations rejected by blacklisting contain poor data quality, and the IRMCD rejects outliers in a robust and physically reasonable manner.

  1. Detecting surface runoff location in a small catchment using distributed and simple observation method

    NASA Astrophysics Data System (ADS)

    Dehotin, Judicaël; Breil, Pascal; Braud, Isabelle; de Lavenne, Alban; Lagouy, Mickaël; Sarrazin, Benoît

    2015-06-01

    Surface runoff is one of the hydrological processes involved in floods, pollution transfer, soil erosion and mudslide. Many models allow the simulation and the mapping of surface runoff and erosion hazards. Field observations of this hydrological process are not common although they are crucial to evaluate surface runoff models and to investigate or assess different kinds of hazards linked to this process. In this study, a simple field monitoring network is implemented to assess the relevance of a surface runoff susceptibility mapping method. The network is based on spatially distributed observations (nine different locations in the catchment) of soil water content and rainfall events. These data are analyzed to determine if surface runoff occurs. Two surface runoff mechanisms are considered: surface runoff by saturation of the soil surface horizon and surface runoff by infiltration excess (also called hortonian runoff). The monitoring strategy includes continuous records of soil surface water content and rainfall with a 5 min time step. Soil infiltration capacity time series are calculated using field soil water content and in situ measurements of soil hydraulic conductivity. Comparison of soil infiltration capacity and rainfall intensity time series allows detecting the occurrence of surface runoff by infiltration-excess. Comparison of surface soil water content with saturated water content values allows detecting the occurrence of surface runoff by saturation of the soil surface horizon. Automatic records were complemented with direct field observations of surface runoff in the experimental catchment after each significant rainfall event. The presented observation method allows the identification of fast and short-lived surface runoff processes at a small spatial and temporal resolution in natural conditions. The results also highlight the relationship between surface runoff and factors usually integrated in surface runoff mapping such as topography, rainfall

  2. Home Videophones Improve Direct Observation in Tuberculosis Treatment: A Mixed Methods Evaluation

    PubMed Central

    Wade, Victoria A.; Karnon, Jonathan; Eliott, Jaklin A.; Hiller, Janet E.

    2012-01-01

    Background The use of direct observation to monitor tuberculosis treatment is controversial: cost, practical difficulties, and lack of patient acceptability limit effectiveness. Telehealth is a promising alternative delivery method for improving implementation. This study aimed to evaluate the clinical and cost-effectiveness of a telehealth service delivering direct observation, compared to an in-person drive-around service. Methodology/Principal Findings The study was conducted within a community nursing service in South Australia. Telehealth patients received daily video calls at home on a desktop videophone provided by the nursing call center. A retrospective cohort study assessed the effectiveness of the telehealth and traditional forms of observation, defined by the proportion of missed observations recorded in case notes. This data was inputted to a model, estimating the incremental cost-effectiveness ratio (ICER) of telehealth. Semi-structured interviews were conducted with current patients, community nursing and Chest Clinic staff, concerning service acceptability, usability and sustainability. The percentage of missed observations for the telehealth service was 12.1 (n = 58), compared to 31.1 for the in-person service (n = 70). Most of the difference of 18.9% (95% CI: 12.2 – 25.4) was due to fewer pre-arranged absences. The economic analysis calculated the ICER to be AUD$1.32 (95% CI: $0.51 – $2.26) per extra day of successful observation. The video service used less staff time, and became dominant if implemented on a larger scale and/or with decreased technology costs. Qualitative analysis found enabling factors of flexible timing, high patient acceptance, staff efficiency, and Chest Clinic support. Substantial technical problems were manageable, and improved liaison between the nursing service and Chest Clinic was an unexpected side-benefit. Conclusions/Significance Home video observation is a patient-centered, resource efficient way of

  3. Intelligent Photovoltaic Systems by Combining the Improved Perturbation Method of Observation and Sun Location Tracking.

    PubMed

    Wang, Yajie; Shi, Yunbo; Yu, Xiaoyu; Liu, Yongjie

    2016-01-01

    Currently, tracking in photovoltaic (PV) systems suffers from some problems such as high energy consumption, poor anti-interference performance, and large tracking errors. This paper presents a solar PV tracking system on the basis of an improved perturbation and observation method, which maximizes photoelectric conversion efficiency. According to the projection principle, we design a sensor module with a light-intensity-detection module for environmental light-intensity measurement. The effect of environmental factors on the system operation is reduced, and intelligent identification of the weather is realized. This system adopts the discrete-type tracking method to reduce power consumption. A mechanical structure with a level-pitch double-degree-of-freedom is designed, and attitude correction is performed by closed-loop control. A worm-and-gear mechanism is added, and the reliability, stability, and precision of the system are improved. Finally, the perturbation and observation method designed and improved by this study was tested by simulated experiments. The experiments verified that the photoelectric sensor resolution can reach 0.344°, the tracking error is less than 2.5°, the largest improvement in the charge efficiency can reach 44.5%, and the system steadily and reliably works.

  4. Intelligent Photovoltaic Systems by Combining the Improved Perturbation Method of Observation and Sun Location Tracking

    PubMed Central

    Wang, Yajie; Shi, Yunbo; Yu, Xiaoyu; Liu, Yongjie

    2016-01-01

    Currently, tracking in photovoltaic (PV) systems suffers from some problems such as high energy consumption, poor anti-interference performance, and large tracking errors. This paper presents a solar PV tracking system on the basis of an improved perturbation and observation method, which maximizes photoelectric conversion efficiency. According to the projection principle, we design a sensor module with a light-intensity-detection module for environmental light-intensity measurement. The effect of environmental factors on the system operation is reduced, and intelligent identification of the weather is realized. This system adopts the discrete-type tracking method to reduce power consumption. A mechanical structure with a level-pitch double-degree-of-freedom is designed, and attitude correction is performed by closed-loop control. A worm-and-gear mechanism is added, and the reliability, stability, and precision of the system are improved. Finally, the perturbation and observation method designed and improved by this study was tested by simulated experiments. The experiments verified that the photoelectric sensor resolution can reach 0.344°, the tracking error is less than 2.5°, the largest improvement in the charge efficiency can reach 44.5%, and the system steadily and reliably works. PMID:27327657

  5. Explaining transgression in respiratory rate observation methods in the emergency department: A classic grounded theory analysis.

    PubMed

    Flenady, Tracy; Dwyer, Trudy; Applegarth, Judith

    2017-09-01

    Abnormal respiratory rates are one of the first indicators of clinical deterioration in emergency department(ED) patients. Despite the importance of respiratory rate observations, this vital sign is often inaccurately recorded on ED observation charts, compromising patient safety. Concurrently, there is a paucity of research reporting why this phenomenon occurs. To develop a substantive theory explaining ED registered nurses' reasoning when they miss or misreport respiratory rate observations. This research project employed a classic grounded theory analysis of qualitative data. Seventy-nine registered nurses currently working in EDs within Australia. Data collected included detailed responses from individual interviews and open-ended responses from an online questionnaire. Classic grounded theory (CGT) research methods were utilised, therefore coding was central to the abstraction of data and its reintegration as theory. Constant comparison synonymous with CGT methods were employed to code data. This approach facilitated the identification of the main concern of the participants and aided in the generation of theory explaining how the participants processed this issue. The main concern identified is that ED registered nurses do not believe that collecting an accurate respiratory rate for ALL patients at EVERY round of observations is a requirement, and yet organizational requirements often dictate that a value for the respiratory rate be included each time vital signs are collected. The theory 'Rationalising Transgression', explains how participants continually resolve this problem. The study found that despite feeling professionally conflicted, nurses often erroneously record respiratory rate observations, and then rationalise this behaviour by employing strategies that adjust the significance of the organisational requirement. These strategies include; Compensating, when nurses believe they are compensating for errant behaviour by enhancing the patient's outcome

  6. A simple method for identifying parameter correlations in partially observed linear dynamic models.

    PubMed

    Li, Pu; Vu, Quoc Dong

    2015-12-14

    Parameter estimation represents one of the most significant challenges in systems biology. This is because biological models commonly contain a large number of parameters among which there may be functional interrelationships, thus leading to the problem of non-identifiability. Although identifiability analysis has been extensively studied by analytical as well as numerical approaches, systematic methods for remedying practically non-identifiable models have rarely been investigated. We propose a simple method for identifying pairwise correlations and higher order interrelationships of parameters in partially observed linear dynamic models. This is made by derivation of the output sensitivity matrix and analysis of the linear dependencies of its columns. Consequently, analytical relations between the identifiability of the model parameters and the initial conditions as well as the input functions can be achieved. In the case of structural non-identifiability, identifiable combinations can be obtained by solving the resulting homogenous linear equations. In the case of practical non-identifiability, experiment conditions (i.e. initial condition and constant control signals) can be provided which are necessary for remedying the non-identifiability and unique parameter estimation. It is noted that the approach does not consider noisy data. In this way, the practical non-identifiability issue, which is popular for linear biological models, can be remedied. Several linear compartment models including an insulin receptor dynamics model are taken to illustrate the application of the proposed approach. Both structural and practical identifiability of partially observed linear dynamic models can be clarified by the proposed method. The result of this method provides important information for experimental design to remedy the practical non-identifiability if applicable. The derivation of the method is straightforward and thus the algorithm can be easily implemented into a

  7. Utility of Liquid Biopsy by Improved PNA-LNA PCR Clamp Method for Detecting EGFR Mutation at Initial Diagnosis of Non-Small-Cell Lung Cancer: Observational Study of 190 Consecutive Cases in Clinical Practice.

    PubMed

    Ito, Kentaro; Suzuki, Yuta; Saiki, Haruko; Sakaguchi, Tadashi; Hayashi, Kosuke; Nishii, Yoichi; Watanabe, Fumiaki; Hataji, Osamu

    2018-03-01

    The clinical benefit of liquid biopsy for unselected patients at initial diagnosis has thus far been unclear. We aimed to evaluate the utility of liquid biopsy at initial diagnosis, as well as the efficacy of epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) based on liquid biopsy results in clinical practice, using the improved peptide nucleic acid-locked nucleic acid (PNA-LNA) PCR clamp method. We routinely performed liquid biopsy using the improved PNA-LNA PCR clamp method for all patients diagnosed with non-small-cell lung cancer (NSCLC) between June 2015 and October 2016. We retrospectively evaluated the reliability of liquid biopsy based either on clinical stage or between sensitizing EGFR mutation and T790M mutation, and the clinical benefit of EGFR-TKI based on the liquid biopsy results in practice. A total of 244 patients underwent liquid biopsies, with 168 patients tested at diagnosis and 22 tested for T790M after pretreatment of EGFR-TKI. For detecting a sensitizing EGFR mutation, the sensitivity, specificity, positive predictive value, and negative predictive value were 72.7%, 100%, 100%, and 93.7% in the group with advanced-stage NSCLC and 0, 100%, not evaluable, and 70.5% in the group with early-stage NSCLC. The positive predictive value and negative predictive value for T790M were 33.3% and 55.6%, respectively. Fourteen patients in the liquid-positive group and 16 patients in the tissue-positive group received EGFR-TKI. The objective response rates of first- and second-generation EGFR-TKI for the liquid-positive and tissue-positive groups were 90.0% and 90.9%, respectively. There was no significant difference in median progression-free survival between the liquid-positive and tissue-positive groups (P = .839). Patients with early-stage NSCLC should not be candidates for this liquid biopsy method. We recommend tissue biopsy as the preferred initial method of molecular analysis, with the exception of patients who are T790M

  8. Comparison of different methods to compute a preliminary orbit of Space Debris using radar observations

    NASA Astrophysics Data System (ADS)

    Ma, Hélène; Gronchi, Giovanni F.

    2014-07-01

    We advertise a new method of preliminary orbit determination for space debris using radar observations, which we call Infang †. We can perform a linkage of two sets of four observations collected at close times. The context is characterized by the accuracy of the range ρ, whereas the right ascension α and the declination δ are much more inaccurate due to observational errors. This method can correct α, δ, assuming the exact knowledge of the range ρ. Considering no perturbations from the J 2 effect, but including errors in the observations, we can compare the new method, the classical method of Gibbs, and the more recent Keplerian integrals method. The development of Infang is still on-going and will be further improved and tested.

  9. In-Hospital Recruitment to Observational Studies of Stroke

    ERIC Educational Resources Information Center

    Pickering, Ruth M.; Kunkel, Dorit; Fitton, Carolyn; Ashburn, Ann; Jenkinson, Damian

    2010-01-01

    The objective of this study was to examine recruitment in three observational follow-up studies of patients with stroke, focusing on reasons for nonparticipation and the role of potential factors in explaining recruitment rates. It comprised secondary analysis of the three studies. Recruitment rates varied between the studies. Between 10 and 50%…

  10. HRO: A New Forward-Scatter Observation Method Using a Ham-Band Beacon

    NASA Astrophysics Data System (ADS)

    Maegawa, K.

    1999-02-01

    A new forward-scatter meteor observation method has been used since 1996 in Japan. It uses its own 50 W continuous wave beacon with a broad directivity antenna on 53.750 MHz. To compensate for the weak echo power from the beacon, observers use SSB mode receivers and narrow band echo detection methods with Fast Fourier Transform software on personal computers. More than 250000 echoes have been counted per year so far. >From these results, diurnal and seasonal variations have been derived and are presented and discussed here. This method (HRO) will continue to play a leading radio observation role in Japan for the future.

  11. An Observational Study of Print Literacy in Canadian Preschool Classrooms

    ERIC Educational Resources Information Center

    Lynch, Jacqueline

    2011-01-01

    The purpose of this study was to examine the role of print literacy in preschool classrooms. There were seven preschool teachers working in central Canada who were observed over three sessions. The process of analytic induction was used to formulate categories based on interviews, classroom observations and documents. The following categories were…

  12. Characterizing Musculoskeletal Injury among Aeromedical Evacuation Personnel: An Observational Study

    DTIC Science & Technology

    2016-09-28

    three phases: a sampling study, laboratory observations, and field observations. In Phase I, 43 active duty AECMs volunteered to complete a...was administered via SurveyMonkey to volunteers from the USAFSAM Education and Training Department and the four active duty AE squadrons. The

  13. An Observational Study of Skilled Memory in Waitresses.

    ERIC Educational Resources Information Center

    Stevens, Joy

    A two-phase study about skilled memory as it is used by waitresses included a participant-observer phase and an observational phase. Participants were three experienced waitresses who had worked at a midtown Manhattan restaurant for 14, 7, and 3 years respectively and a team of 5 confederate customers. Waitresses and customers wore microphones.…

  14. The Value of Mixed Methods Research: A Mixed Methods Study

    ERIC Educational Resources Information Center

    McKim, Courtney A.

    2017-01-01

    The purpose of this explanatory mixed methods study was to examine the perceived value of mixed methods research for graduate students. The quantitative phase was an experiment examining the effect of a passage's methodology on students' perceived value. Results indicated students scored the mixed methods passage as more valuable than those who…

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

    PubMed

    Malmivaara, Antti

    2016-09-01

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

  16. 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.

  17. Theoretical and Observational Studies of Meteor Interactions with the Ionosphere

    DTIC Science & Technology

    2006-06-01

    within an order of magnitude. The histograms of scattering mass, calculated from data collected at the ALTAIR rada are contained in Figure 1 . These...RTO-MP-IST-056 12 - 1 UNCLASSIFIED/UNLIMITED UNCLASSIFIED/UNLIMITED Theoretical and Observational Studies of Meteor Interactions with the...Observational Studies of Meteor Interactions with the Ionosphere. In Characterising the Ionosphere (pp. 12- 1 – 12-12). Meeting Proceedings RTO-MP-IST-056

  18. Resuscitative Hyperkalemia in Noncrush Trauma: A Prospective, Observational Study

    DTIC Science & Technology

    2006-12-01

    Resuscitative Hyperkalemia in Noncrush Trauma: A Prospective, Observational Study Robert M. Perkins,*† Matthew C. Aboudara,* Kevin C. Abbott,*† and...Surgical Research, San Antonio, Texas The trauma patient is exposed to physiologic processes and life-saving interventions that predispose to hyperkalemia ...in the care of the massively traumatized patient may or may not increase the risk for hyperkalemia . This prospective, observational study was

  19. Multiple indices method for real-time tsunami inundation forecast using a dense offshore observation network

    NASA Astrophysics Data System (ADS)

    Yamamoto, N.; Aoi, S.; Hirata, K.; Suzuki, W.; Kunugi, T.; Nakamura, H.

    2015-12-01

    We started to develop a new methodology for real-time tsunami inundation forecast system (Aoi et al., 2015, this meeting) using densely offshore tsunami observations of the Seafloor Observation Network for Earthquakes and Tsunamis (S-net), which is under construction along the Japan Trench (Kanazawa et al., 2012, JpGU; Uehira et al., 2015, IUGG). In our method, the most important concept is involving any type and/or form uncertainties in the tsunami forecast, which cannot be dealt with any of standard linear/nonlinear least square approaches. We first prepare a Tsunami Scenario Bank (TSB), which contains offshore tsunami waveforms at the S-net stations and tsunami inundation information calculated from any possible tsunami source. We then quickly select several acceptable tsunami scenarios that can explain offshore observations by using multiple indices and appropriate thresholds, after a tsunami occurrence. At that time, possible tsunami inundations coupled with selected scenarios are forecasted (Yamamoto et al., 2014, AGU). Currently, we define three indices: correlation coefficient and two variance reductions, whose L2-norm part is normalized either by observations or calculations (Suzuki et al., 2015, JpGU; Yamamoto et al., 2015, IUGG). In this study, we construct the TSB, which contains various tsunami source models prepared for the probabilistic tsunami hazard assessment in the Japan Trench region (Hirata et al., 2014, AGU). To evaluate the propriety of our method, we adopt the fault model based on the 2011 Tohoku earthquake as a pseudo "observation". We also calculate three indices using coastal maximum tsunami height distributions between observation and calculation. We then obtain the correlation between coastal and offshore indices. We notice that the index value of coastal maximum tsunami heights is closer to 1 than the index value of offshore waveforms, i.e., the coastal maximum tsunami height may be predictable within appropriate thresholds defined for

  20. Maximum ikelihood estimation for the double-count method with independent observers

    USGS Publications Warehouse

    Manly, Bryan F.J.; McDonald, Lyman L.; Garner, Gerald W.

    1996-01-01

    Data collected under a double-count protocol during line transect surveys were analyzed using new maximum likelihood methods combined with Akaike's information criterion to provide estimates of the abundance of polar bear (Ursus maritimus Phipps) in a pilot study off the coast of Alaska. Visibility biases were corrected by modeling the detection probabilities using logistic regression functions. Independent variables that influenced the detection probabilities included perpendicular distance of bear groups from the flight line and the number of individuals in the groups. A series of models were considered which vary from (1) the simplest, where the probability of detection was the same for both observers and was not affected by either distance from the flight line or group size, to (2) models where probability of detection is different for the two observers and depends on both distance from the transect and group size. Estimation procedures are developed for the case when additional variables may affect detection probabilities. The methods are illustrated using data from the pilot polar bear survey and some recommendations are given for design of a survey over the larger Chukchi Sea between Russia and the United States.

  1. Mosaic CCD method: A new technique for observing dynamics of cometary magnetospheres

    NASA Technical Reports Server (NTRS)

    Saito, T.; Takeuchi, H.; Kozuba, Y.; Okamura, S.; Konno, I.; Hamabe, M.; Aoki, T.; Minami, S.; Isobe, S.

    1992-01-01

    On April 29, 1990, the plasma tail of Comet Austin was observed with a CCD camera on the 105-cm Schmidt telescope at the Kiso Observatory of the University of Tokyo. The area of the CCD used in this observation is only about 1 sq cm. When this CCD is used on the 105-cm Schmidt telescope at the Kiso Observatory, the area corresponds to a narrow square view of 12 ft x 12 ft. By comparison with the photograph of Comet Austin taken by Numazawa (personal communication) on the same night, we see that only a small part of the plasma tail can be photographed at one time with the CCD. However, by shifting the view on the CCD after each exposure, we succeeded in imaging the entire length of the cometary magnetosphere of 1.6 x 10(exp 6) km. This new technique is called 'the mosaic CCD method'. In order to study the dynamics of cometary plasma tails, seven frames of the comet from the head to the tail region were twice imaged with the mosaic CCD method and two sets of images were obtained. Six microstructures, including arcade structures, were identified in both the images. Sketches of the plasma tail including microstructures are included.

  2. A method for three-dimensional quantitative observation of the microstructure of biological samples

    NASA Astrophysics Data System (ADS)

    Wang, Pengfei; Chen, Dieyan; Ma, Wanyun; Wu, Hongxin; Ji, Liang; Sun, Jialin; Lv, Danyu; Zhang, Lu; Li, Ying; Tian, Ning; Zheng, Jinggao; Zhao, Fengying

    2009-07-01

    Contemporary biology has developed into the era of cell biology and molecular biology, and people try to study the mechanism of all kinds of biological phenomena at the microcosmic level now. Accurate description of the microstructure of biological samples is exigent need from many biomedical experiments. This paper introduces a method for 3-dimensional quantitative observation on the microstructure of vital biological samples based on two photon laser scanning microscopy (TPLSM). TPLSM is a novel kind of fluorescence microscopy, which has excellence in its low optical damage, high resolution, deep penetration depth and suitability for 3-dimensional (3D) imaging. Fluorescent stained samples were observed by TPLSM, and afterward the original shapes of them were obtained through 3D image reconstruction. The spatial distribution of all objects in samples as well as their volumes could be derived by image segmentation and mathematic calculation. Thus the 3-dimensionally and quantitatively depicted microstructure of the samples was finally derived. We applied this method to quantitative analysis of the spatial distribution of chromosomes in meiotic mouse oocytes at metaphase, and wonderful results came out last.

  3. Method for optimizing channelized quadratic observers for binary classification of large-dimensional image datasets

    PubMed Central

    Kupinski, M. K.; Clarkson, E.

    2015-01-01

    We present a new method for computing optimized channels for channelized quadratic observers (CQO) that is feasible for high-dimensional image data. The method for calculating channels is applicable in general and optimal for Gaussian distributed image data. Gradient-based algorithms for determining the channels are presented for five different information-based figures of merit (FOMs). Analytic solutions for the optimum channels for each of the five FOMs are derived for the case of equal mean data for both classes. The optimum channels for three of the FOMs under the equal mean condition are shown to be the same. This result is critical since some of the FOMs are much easier to compute. Implementing the CQO requires a set of channels and the first- and second-order statistics of channelized image data from both classes. The dimensionality reduction from M measurements to L channels is a critical advantage of CQO since estimating image statistics from channelized data requires smaller sample sizes and inverting a smaller covariance matrix is easier. In a simulation study we compare the performance of ideal and Hotelling observers to CQO. The optimal CQO channels are calculated using both eigenanalysis and a new gradient-based algorithm for maximizing Jeffrey's divergence (J). Optimal channel selection without eigenanalysis makes the J-CQO on large-dimensional image data feasible. PMID:26366764

  4. The Effects of Three Methods of Observation on Couples in Interactional Research.

    ERIC Educational Resources Information Center

    Carpenter, Linda J.; Merkel, William T.

    1988-01-01

    Assessed the effects of three different methods of observation of couples (one-way mirror, audio recording, and video recording) on 30 volunteer, nonclinical married couples. Results suggest that types of observation do not produce significantly different effects on nonclinical couples. (Author/ABL)

  5. Deriving brown carbon from multiwavelength absorption measurements: Method and application to AERONET and Aethalometer observations

    DOE PAGES

    Wang, X.; Heald, C. L.; Sedlacek, A.; ...

    2016-10-13

    The radiative impact of organic aerosols (OA) is a large source of uncertainty in estimating the global direct radiative effect (DRE) of aerosols. This radiative impact includes not only light scattering but also light absorption from a subclass of OA referred to as brown carbon (BrC). However the absorption properties of BrC are poorly understood leading to large uncertainties in modelling studies. To obtain observational constraints from measurements, a simple Absorption Ångström Exponent (AAE) method is often used to separate the contribution of BrC absorption from that of black carbon (BC). However, this attribution method is based on assumptions regardingmore » the spectral dependence of BC that are often violated in the ambient atmosphere. Here we develop a new method that decreases the uncertainties associated with estimating BrC absorption. By applying this method to multi-wavelength absorption aerosol optical depth (AAOD) measurements at AERONET sites worldwide and surface aerosol absorption measurements at multiple ambient sites, we estimate that BrC globally contributes 6-40% of the absorption at 440nm. We find that the mass absorption coefficient of OA (OA-MAC) is positively correlated with BC/OA mass ratio. Based on the variability of BC properties and BC/OA emission ratio, we estimate a range of 0.05-1.2 m 2/g for OA-MAC at 440nm. Using the combination of AERONET and OMI UV absorption observations we estimate that the AAE 388/440nm for BrC is generally ~4 world-wide, with a smaller value in Europe (< 2). Our analyses of two surface sites (Cape Cod, to the southeast of Boston, and the GoAmazon2014/5 T3 site, to the west of Manaus, Brazil) reveal no significant relationship between BrC absorptivity and photochemical aging in typical urban influenced conditions. However, the absorption of BrC measured during the biomass burning season near Manaus is found to decrease with photochemical aging with a lifetime of ~1 day. This lifetime is comparable to

  6. Nontraditional method for determining unperturbed orbits of unknown space objects using incomplete optical observational data

    NASA Astrophysics Data System (ADS)

    Perov, N. I.

    1985-02-01

    A physical-geometrical method for computing the orbits of earth satellites on the basis of an inadequate number of angular observations (N3) was developed. Specifically, a new method has been developed for calculating the elements of Keplerian orbits of unidentified artificial satellites using two angular observations (alpha sub k, S sub k, k = 1). The first section gives procedures for determining the topocentric distance to AES on the basis of one optical observation. This is followed by description of a very simple method for determining unperturbed orbits using two satellite position vectors and a time interval which is applicable even in the case of antiparallel AED position vectors, a method designated the R sub 2 iterations method.

  7. Studies of Accreting Neutron Stars with RXTE Cycle 4 Observations: III: TOO Observations of Atoll Sources

    NASA Technical Reports Server (NTRS)

    Paciesas, William S.

    2002-01-01

    NASA Grant NAG 5-9244 provided funds for the research projects 'ASM-Triggered TOO Observations of Kilohertz Oscillations in Five Atoll Sources' and 'Further Measurements of the Kilohertz Oscillations in 4U 1705-44' approved under the Rossi X-ray Timing Explorer (RXTE) Guest Observer Program Cycle 4 and funded under the 1999 NASA Astrophysics Data Program. The principal investigator of the observing time proposals was Dr. E. C. Ford (U. of Amsterdam). The grant was funded for one year beginning 3/15/2000. The original ADP proposal was submitted by Prof. Jan van Paradijs, who passed away in 1999 before the funds were distributed. Prof. Wilham S. Padesas administered the grant during the period of performance. In spite of a wealth of observational data on the kHz QPO in low-mass X-ray binaries (LMXBs), the interpretation of this phenomenon is currently uncertain because the pairs of kHz QPO peaks and the oscillations seen in some Type I X-ray bursts are almost, but not quite, connected by a simple beat frequency relation. Further systematic studies of systems with known QPOs are required in order to better understand the phenomenon. The proposals were intended to contribute to a solution to this confusion by observing the sources as they vary over a wide range of X-ray flux. RXTE target-of-opportunity observations of six transient atoll sources, 4U 0614+09, KS 1732-260, Ser X-1, 4U 1702-42, 4U 1820-30 and 4U 1705-44 were to be performed at various flux levels based on ASM measurements.

  8. "Lies, damned lies ..." and observational studies in comparative effectiveness research.

    PubMed

    Albert, Richard K

    2013-06-01

    A new federal initiative has allocated $1.1 billion to comparative effectiveness research, and many have emphasized the importance of including observational studies in this effort. The rationale for using observational studies to assess comparative effectiveness is based on concerns that randomized controlled trials (RCTs) are not "real world" because they enroll homogeneous patient populations, measure study outcomes that are not important to patients, use protocols that are overly complex, are conducted in specialized centers, and use study treatments that are not consistent with usual care, and that RCTs are not always feasible because of a lack of equipoise, the need to assess delayed endpoints, and concerns that they take years to complete and are expensive. This essay questions the validity of each of these proposed limitations, summarizes concerns raised about the accuracy of results generated by observational studies, provides some examples of discrepancies between results of observational studies and RCTs that pertain to pulmonary and critical care, and suggests that using observational studies for comparative effectiveness research may increase rather than decrease the cost of health care and may harm patients.

  9. Evaluation of Xerostomia in Different Psychological Disorders: An Observational Study

    PubMed Central

    Chandrappa, Pramod Redder; Patil, Snehal; Roodmal, Seema Yadav; Kumarswamy, Akshay; Chappi, Mounesh Kumar

    2016-01-01

    Introduction Psychiatric diseases like anxiety, depression, schizophrenia and bipolar disorders are increasing at an alarming rate. These diseases can affect the quantity and quality of saliva leading to multiple oral diseases. Although many researchers have evaluated xerostomia in general population, its prevalence is not been assessed in patients suffering from different psychological disorders. Aim To investigate the prevalence of xerostomia and to assess the correlation between xerostomia and dryness of lip and mucosa in different psychological disorders. Materials and Methods A cross-sectional observational study was conducted over a period of six months in Department of Psychiatry and Department of Oral Medicine. Patients with anxiety, depression, schizophrenia and bipolar disorder, as diagnosed by an experienced psychiatrist, were given a questionnaire to evaluate the xerostomia. Patients with symptoms of xerostomia were subjected to oral examination by a skilled oral diagnostician to check for dryness of lips and mucosa. One hundred patients from each group of psychiatric diseases were included in the study using a consecutive sampling technique. An equal number of healthy individuals reporting to oral medicine department for routine oral screening were included as control group after initial psychiatric evaluation. Results In this study statistically significant increase in the xerostomia in psychiatric patients was recorded when compared to the control group (p<0.01). Xerostomia was significantly higher in anxiety patients (51%) followed by depression (47%), bipolar disorder (41%), schizophrenia (39%) and control group (27%). The majority of the psychiatric patients had ‘moderate’ to ‘severe’ xerostomia whereas the control group had ‘mild’ xerostomia. Xerostomia was significantly higher in younger age group (18–49 years) than in older age group and females patients had higher xerostomia than male patients. Psychiatric patients had

  10. Development of Creative Behavior Observation Form: A Study on Validity and Reliability

    ERIC Educational Resources Information Center

    Dere, Zeynep; Ömeroglu, Esra

    2018-01-01

    This study, Creative Behavior Observation Form was developed to assess creativity of the children. While the study group on the reliability and validity of Creative Behavior Observation Form was being developed, 257 children in total who were at the ages of 5-6 were used as samples with stratified sampling method. Content Validity Index (CVI) and…

  11. Preequating with Empirical Item Characteristic Curves: An Observed-Score Preequating Method

    ERIC Educational Resources Information Center

    Zu, Jiyun; Puhan, Gautam

    2014-01-01

    Preequating is in demand because it reduces score reporting time. In this article, we evaluated an observed-score preequating method: the empirical item characteristic curve (EICC) method, which makes preequating without item response theory (IRT) possible. EICC preequating results were compared with a criterion equating and with IRT true-score…

  12. Subtle Emotional Process in Early Childhood Pedagogy: Evaluating the Contribution of the Tavistock Observation Method

    ERIC Educational Resources Information Center

    Elfer, Peter

    2017-01-01

    Nursery experience is now common for young children and their families. Questions of quality have focussed mainly on safety and early learning. The roles of subtle emotional processes in daily pedagogic interactions have received surprisingly little attention. This paper discusses the Tavistock Observation Method (TOM), a naturalistic method of…

  13. 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.

  14. A Reliable, Feasible Method to Observe Neighborhoods at High Spatial Resolution

    PubMed Central

    Kepper, Maura M.; Sothern, Melinda S.; Theall, Katherine P.; Griffiths, Lauren A.; Scribner, Richard; Tseng, Tung-Sung; Schaettle, Paul; Cwik, Jessica M.; Felker-Kantor, Erica; Broyles, Stephanie T.

    2016-01-01

    Introduction Systematic social observation (SSO) methods traditionally measure neighborhoods at street level and have been performed reliably using virtual applications to increase feasibility. Research indicates that collection at even higher spatial resolution may better elucidate the health impact of neighborhood factors, but whether virtual applications can reliably capture social determinants of health at the smallest geographic resolution (parcel level) remains uncertain. This paper presents a novel, parcel-level SSO methodology and assesses whether this new method can be collected reliably using Google Street View and is feasible. Methods Multiple raters (N=5) observed 42 neighborhoods. In 2016, inter-rater reliability (observed agreement and kappa coefficient) was compared for four SSO methods: (1) street-level in person; (2) street-level virtual; (3) parcel-level in person; and (4) parcel-level virtual. Intra-rater reliability (observed agreement and kappa coefficient) was calculated to determine whether parcel-level methods produce results comparable to traditional street-level observation. Results Substantial levels of inter-rater agreement were documented across all four methods; all methods had >70% of items with at least substantial agreement. Only physical decay showed higher levels of agreement (83% of items with >75% agreement) for direct versus virtual rating source. Intra-rater agreement comparing street- versus parcel-level methods resulted in observed agreement >75% for all but one item (90%). Conclusions Results support the use of Google Street View as a reliable, feasible tool for performing SSO at the smallest geographic resolution. Validation of a new parcel-level method collected virtually may improve the assessment of social determinants contributing to disparities in health behaviors and outcomes. PMID:27989289

  15. Radiation energy budget studies using collocated AVHRR and ERBE observations

    NASA Technical Reports Server (NTRS)

    Ackerman, Steven A.; Inoue, Toshiro

    1994-01-01

    Changes in the energy balance at the top of the atmosphere are specified as a function of atmospheric and surface properties using observations from the Advanced Very High Resolution Radiometer (AVHRR) and the Earth Radiation Budget Experiment (ERBE) scanner. By collocating the observations from the two instruments, flown on NOAA-9, the authors take advantage of the remote-sensing capabilities of each instrument. The AVHRR spectral channels were selected based on regions that are strongly transparent to clear sky conditions and are therefore useful for characterizing both surface and cloud-top conditions. The ERBE instruments make broadband observations that are important for climate studies. The approach of collocating these observations in time and space is used to study the radiative energy budget of three geographic regions: oceanic, savanna, and desert.

  16. Live versus Video Observations: Comparing the Reliability and Validity of Two Methods of Assessing Classroom Quality

    ERIC Educational Resources Information Center

    Curby, Timothy W.; Johnson, Price; Mashburn, Andrew J.; Carlis, Lydia

    2016-01-01

    When conducting classroom observations, researchers are often confronted with the decision of whether to conduct observations live or by using pre-recorded video. The present study focuses on comparing and contrasting observations of live and video administrations of the Classroom Assessment Scoring System-PreK (CLASS-PreK). Associations between…

  17. Some observations on a new numerical method for solving Navier-Stokes equations

    NASA Technical Reports Server (NTRS)

    Kumar, A.

    1981-01-01

    An explicit-implicit technique for solving Navier-Stokes equations is described which, is much less complex than other implicit methods. It is used to solve a complex, two-dimensional, steady-state, supersonic-flow problem. The computational efficiency of the method and the quality of the solution obtained from it at high Courant-Friedrich-Lewy (CFL) numbers are discussed. Modifications are discussed and certain observations are made about the method which may be helpful in using it successfully.

  18. Observation of Bright Ring Phenomenon for Red Blood Cells by Lattice Boltzmann Method

    NASA Astrophysics Data System (ADS)

    Kim, Young Woo; Moon, Ji Young; Lee, Joon Sang

    2017-11-01

    RBC (Red Blood Cell) aggregation is one of interests for various biomechanical fields such as cell chip or visualization. The unique phenomenon called ``bright ring'' is due to RBC aggregation in pulsatile flow of blood. Shear rate and flow acceleration on RBC causes them to repeat aggregating and scattering from center of the channel. The reason that this phenomenon is called bright ring is because that when observed by ultrasound imaging, the bright ring occurs periodically. Many studies tried to observe this bright ring phenomenon experimentally. However, there are yet not many studies trying to make use of this phenomenon for practical purposes. Bright ring phenomenon has high potential when used for cell separation or other microchip devices. In this paper, the Lattice Boltzmann method is used to control this bright ring phenomenon. The purpose of this paper is to find conditions when bright ring phenomenon occurs, and to control the aggregating-scattering frequency and degree. Deformability of RBC is calculated following the work of Moon JY et al. (2016). The result of this paper could be further extended to the optimization of cell-separating microchips. This work was also supported by the National Research Foundation of Korea (NRF) Grant funded by the Korean Government (MSIP) (No. 2015R1A5A1037668) and Brain Korea 21 Plus.

  19. Teacher Effectiveness and Causal Inference in Observational Studies

    ERIC Educational Resources Information Center

    Rose, Roderick A.

    2013-01-01

    An important target of education policy is to improve overall teacher effectiveness using evidence-based policies. Randomized control trials (RCTs), which randomly assign study participants or groups of participants to treatment and control conditions, are not always practical or possible and observational studies using rigorous quasi-experimental…

  20. External Validation of the HERNIAscore: An Observational Study.

    PubMed

    Cherla, Deepa V; Moses, Maya L; Mueck, Krislynn M; Hannon, Craig; Ko, Tien C; Kao, Lillian S; Liang, Mike K

    2017-09-01

    The HERNIAscore is a ventral incisional hernia (VIH) risk assessment tool that uses only preoperative variables and predictable intraoperative variables. The aim of this study was to validate and modify, if needed, the HERNIAscore in an external dataset. This was a retrospective observational study of all patients undergoing resection for gastrointestinal malignancy from 2011 through 2015 at a safety-net hospital. The primary end point was clinical postoperative VIH. Patients were stratified into low-risk, medium-risk, and high-risk groups based on HERNIAscore. A revised HERNIAscore was calculated with the addition of earlier abdominal operation as a categorical variable. Cox regression of incisional hernia with stratification by risk class was performed. Incidence rates of clinical VIH formation within each risk class were also calculated. Two hundred and forty-seven patents were enrolled. On Cox regression, in addition to the 3 variables of the HERNIAscore (BMI, COPD, and incision length), earlier abdominal operation was also predictive of VIH. The revised HERNIAscore demonstrated improved predictive accuracy for clinical VIH. Although the original HERNIAscore effectively stratified the risk of an incisional radiographic VIH developing, the revised HERNIAscore provided a statistically significant stratification for both clinical and radiographic VIHs in this patient cohort. We have externally validated and improved the HERNIAscore. The revised HERNIAscore uses BMI, incision length, COPD, and earlier abdominal operation to predict risk of postoperative incisional hernia. Future research should assess methods to prevent incisional hernias in moderate-to-high risk patients. Copyright © 2017 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  1. Classical methods and modern analysis for studying fungal diversity

    Treesearch

    John Paul Schmit

    2005-01-01

    In this chapter, we examine the use of classical methods to study fungal diversity. Classical methods rely on the direct observation of fungi, rather than sampling fungal DNA. We summarize a wide variety of classical methods, including direct sampling of fungal fruiting bodies, incubation of substrata in moist chambers, culturing of endophytes, and particle plating. We...

  2. Classical Methods and Modern Analysis for Studying Fungal Diversity

    Treesearch

    J. P. Schmit; D. J. Lodge

    2005-01-01

    In this chapter, we examine the use of classical methods to study fungal diversity. Classical methods rely on the direct observation of fungi, rather than sampling fungal DNA. We summarize a wide variety of classical methods, including direct sampling of fungal fruiting bodies, incubation of substrata in moist chambers, culturing of endophytes, and particle plating. We...

  3. Applications of neural network methods to the processing of earth observation satellite data.

    PubMed

    Loyola, Diego G

    2006-03-01

    The new generation of earth observation satellites carries advanced sensors that will gather very precise data for studying the Earth system and global climate. This paper shows that neural network methods can be successfully used for solving forward and inverse remote sensing problems, providing both accurate and fast solutions. Two examples of multi-neural network systems for the determination of cloud properties and for the retrieval of total columns of ozone using satellite data are presented. The developed algorithms based on multi-neural network are currently being used for the operational processing of European atmospheric satellite sensors and will play a key role in related satellite missions planed for the near future.

  4. Lateralization in motor facilitation during action observation: a TMS study.

    PubMed

    Aziz-Zadeh, Lisa; Maeda, Fumiko; Zaidel, Eran; Mazziotta, John; Iacoboni, Marco

    2002-05-01

    Action observation facilitates corticospinal excitability. This is presumably due to a premotor neural system that is active when we perform actions and when we observe actions performed by others. It has been speculated that this neural system is a precursor of neural systems subserving language. If this theory is true, we may expect hemispheric differences in the motor facilitation produced by action observation, with the language-dominant left hemisphere showing stronger facilitation than the right hemisphere. Furthermore, it has been suggested that body parts are recognized via cortical regions controlling sensory and motor processing associated with that body part. If this is true, then corticospinal facilitation during action observation should be modulated by the laterality of the observed body part. The present study addressed these two issues using TMS for each motor cortex separately as participants observed actions being performed by a left hand, a right hand, or a control stimulus on the computer screen. We found no overall difference between the right and left hemisphere for motor-evoked potential (MEP) size during action observation. However, when TMS was applied to the left motor cortex, MEPs were larger while observing right hand actions. Likewise, when TMS was applied to the right motor cortex, MEPs were larger while observing left hand actions. Our data do not suggest left hemisphere superiority in the facilitating effects of action observation on the motor system. However, they do support the notion of a sensory-motor loop according to which sensory stimulus properties (for example, the image of a left hand or a right hand) directly affect motor cortex activity, even when no motor output is required. The pattern of this effect is congruent with the pattern of motor representation in each hemisphere.

  5. Methods to study Drosophila immunity.

    PubMed

    Neyen, Claudine; Bretscher, Andrew J; Binggeli, Olivier; Lemaitre, Bruno

    2014-06-15

    Innate immune mechanisms are well conserved throughout evolution, and many theoretical concepts, molecular pathways and gene networks are applicable to invertebrate model organisms as much as vertebrate ones. Drosophila immunity research benefits from an easily manipulated genome, a fantastic international resource of transgenic tools and over a quarter century of accumulated techniques and approaches to study innate immunity. Here we present a short collection of ways to challenge the fruit fly immune system with various pathogens and parasites, as well as read-outs to assess its functions, including cellular and humoral immune responses. Our review covers techniques for assessing the kinetics and efficiency of immune responses quantitatively and qualitatively, such as survival analysis, bacterial persistence, antimicrobial peptide gene expression, phagocytosis and melanisation assays. Finally, we offer a toolkit of Drosophila strains available to the research community for current and future research. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. A stepwedge-based method for measuring breast density: observer variability and comparison with human reading

    NASA Astrophysics Data System (ADS)

    Diffey, Jenny; Berks, Michael; Hufton, Alan; Chung, Camilla; Verow, Rosanne; Morrison, Joanna; Wilson, Mary; Boggis, Caroline; Morris, Julie; Maxwell, Anthony; Astley, Susan

    2010-04-01

    Breast density is positively linked to the risk of developing breast cancer. We have developed a semi-automated, stepwedge-based method that has been applied to the mammograms of 1,289 women in the UK breast screening programme to measure breast density by volume and area. 116 images were analysed by three independent operators to assess inter-observer variability; 24 of these were analysed on 10 separate occasions by the same operator to determine intra-observer variability. 168 separate images were analysed using the stepwedge method and by two radiologists who independently estimated percentage breast density by area. There was little intra-observer variability in the stepwedge method (average coefficients of variation 3.49% - 5.73%). There were significant differences in the volumes of glandular tissue obtained by the three operators. This was attributed to variations in the operators' definition of the breast edge. For fatty and dense breasts, there was good correlation between breast density assessed by the stepwedge method and the radiologists. This was also observed between radiologists, despite significant inter-observer variation. Based on analysis of thresholds used in the stepwedge method, radiologists' definition of a dense pixel is one in which the percentage of glandular tissue is between 10 and 20% of the total thickness of tissue.

  7. 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.

  8. A Coarse Alignment Method Based on Digital Filters and Reconstructed Observation Vectors

    PubMed Central

    Xu, Xiang; Xu, Xiaosu; Zhang, Tao; Li, Yao; Wang, Zhicheng

    2017-01-01

    In this paper, a coarse alignment method based on apparent gravitational motion is proposed. Due to the interference of the complex situations, the true observation vectors, which are calculated by the apparent gravity, are contaminated. The sources of the interference are analyzed in detail, and then a low-pass digital filter is designed in this paper for eliminating the high-frequency noise of the measurement observation vectors. To extract the effective observation vectors from the inertial sensors’ outputs, a parameter recognition and vector reconstruction method are designed, where an adaptive Kalman filter is employed to estimate the unknown parameters. Furthermore, a robust filter, which is based on Huber’s M-estimation theory, is developed for addressing the outliers of the measurement observation vectors due to the maneuver of the vehicle. A comprehensive experiment, which contains a simulation test and physical test, is designed to verify the performance of the proposed method, and the results show that the proposed method is equivalent to the popular apparent velocity method in swaying mode, but it is superior to the current methods while in moving mode when the strapdown inertial navigation system (SINS) is under entirely self-contained conditions. PMID:28353682

  9. New methods to benchmark simulations of accreting black holes systems against observations

    NASA Astrophysics Data System (ADS)

    Markoff, Sera; Chatterjee, Koushik; Liska, Matthew; Tchekhovskoy, Alexander; Hesp, Casper; Ceccobello, Chiara; Russell, Thomas

    2017-08-01

    The field of black hole accretion has been significantly advanced by the use of complex ideal general relativistic magnetohydrodynamics (GRMHD) codes, now capable of simulating scales from the event horizon out to ~10^5 gravitational radii at high resolution. The challenge remains how to test these simulations against data, because the self-consistent treatment of radiation is still in its early days, and is complicated by dependence on non-ideal/microphysical processes not yet included in the codes. On the other extreme, a variety of phenomenological models (disk, corona, jet, wind) can well-describe spectra or variability signatures in a particular waveband, although often not both. To bring these two methodologies together, we need robust observational “benchmarks” that can be identified and studied in simulations. I will focus on one example of such a benchmark, from recent observational campaigns on black holes across the mass scale: the jet break. I will describe new work attempting to understand what drives this feature by searching for regions that share similar trends in terms of dependence on accretion power or magnetisation. Such methods can allow early tests of simulation assumptions and help pinpoint which regions will dominate the light production, well before full radiative processes are incorporated, and will help guide the interpretation of, e.g. Event Horizon Telescope data.

  10. A simple method for correcting spatially resolved solar intensity oscillation observations for variations in scattered light

    NASA Technical Reports Server (NTRS)

    Jefferies, S. M.; Duvall, T. L., Jr.

    1991-01-01

    A measurement of the intensity distribution in an image of the solar disk will be corrupted by a spatial redistribution of the light that is caused by the earth's atmosphere and the observing instrument. A simple correction method is introduced here that is applicable for solar p-mode intensity observations obtained over a period of time in which there is a significant change in the scattering component of the point spread function. The method circumvents the problems incurred with an accurate determination of the spatial point spread function and its subsequent deconvolution from the observations. The method only corrects the spherical harmonic coefficients that represent the spatial frequencies present in the image and does not correct the image itself.

  11. A Novel Observational Method for Assessing Acute Responses to Cannabis: Preliminary Validation Using Legal Market Strains.

    PubMed

    Bidwell, L Cinnamon; Mueller, Raeghan; YorkWilliams, Sophie L; Hagerty, Sarah; Bryan, Angela D; Hutchison, Kent E

    2018-01-01

    Background: The development of novel cannabis research methods that are compatible with current federal regulations is imperative to conduct studies of the effects of legal market cannabis. There is very little research on higher strength, higher Δ9-tetrahydrocannabinol (THC), which has become increasingly available since legalization. Research on strains containing cannabidiol (CBD), a second primary, but nonpsychotomimetic, cannabinoid, is very limited. Materials and Methods: Using a novel observational methodology, regular cannabis users were asked to use one of two legal market cannabis strains that they purchased from a local dispensary (one strain containing 8% THC and 16% CBD (THC+CBD) and one containing a 17% THC concentration, but no CBD (THC). After using their suggested cannabis strain as they typically would for a 3-day period, participants returned to the laboratory immediately after their final use. Measures included a blood draw to measure cannabinoid blood levels and circulating cytokines, self-reported subjective drug effects, and verbal recall memory. Results: Analysis of CBD/THC concentration levels in the blood following the 3-day strain manipulation suggests that all, but one participant ( n =23/24) followed instructions and used their assigned strain. Individuals in the THC group ( n =11) smoked no more than their usual amount, and participants who used the THC+CBD ( n =12) strain smoked more than their reported usual amount, but did not have significantly different THC+metabolite blood levels from the THC group. The THC+CBD strain was also associated with less desire to smoke, lower levels of subjective drug effects, and lower levels of circulating cytokines (TNF-α, IL-6, and IL-1β) immediately after use. Conclusions: Initial results support the feasibility of this novel observational methodology involving brief manipulation of strain use. Preliminary findings indicate that participants may self-titrate cannabis use based on cannabinoid

  12. SABRE observations of Pi2 pulsations: case studies

    NASA Astrophysics Data System (ADS)

    Bradshaw, E. G.; Lester, M.

    1997-01-01

    The characteristics of substorm-associated Pi2 pulsations observed by the SABRE coherent radar system during three separate case studies are presented. The SABRE field of view is well positioned to observe the differences between the auroral zone pulsation signature and that observed at mid-latitudes. During the first case study the SABRE field of view is initially in the eastward electrojet, equatorward and to the west of the substorm-enhanced electrojet current. As the interval progresses, the western, upward field-aligned current of the substorm current wedge moves westward across the longitudes of the radar field of view. The westward motion of the wedge is apparent in the spatial and temporal signatures of the associated Pi2 pulsation spectra and polarisation sense. During the second case study, the complex field-aligned and ionospheric currents associated with the pulsation generation region move equatorward into the SABRE field of view and then poleward out of it again after the third pulsation in the series. The spectral content of the four pulsations during the interval indicate different auroral zone and mid-latitude signatures. The final case study is from a period of low magnetic activity when SABRE observes a Pi2 pulsation signature from regions equatorward of the enhanced substorm currents. There is an apparent mode change between the signature observed by SABRE in the ionosphere and that on the ground by magnetometers at latitudes slightly equatorward of the radar field of view. The observations are discussed in terms of published theories of the generation mechanisms for this type of pulsation. Different signatures are observed by SABRE depending on the level of magnetic activity and the position of the SABRE field of view relative to the pulsation generation region. A twin source model for Pi2 pulsation generation provides the clearest explanation of the signatures observed Acknowledgements. The authors are grateful to Prof. D. J. Southwood

  13. Multicenter Observational Prehospital Resuscitation on Helicopter Study (PROHS)

    PubMed Central

    Holcomb, John B.; Swartz, Michael D.; DeSantis, Stacia M.; Greene, Thomas J.; Fox, Erin E.; Stein, Deborah M.; Bulger, Eileen M.; Kerby, Jeffrey D.; Goodman, Michael; Schreiber, Martin A.; Zielinski, Martin D.; O’Keeffe, Terence; Inaba, Kenji; Tomasek, Jeffrey S.; Podbielski, Jeanette M.; Appana, Savitri; Yi, Misung; Wade, Charles E.

    2017-01-01

    BACKGROUND Earlier use of in-hospital plasma, platelets and red blood cells (RBCs) has improved survival in trauma patients with severe hemorrhage. Retrospective studies have associated improved early survival with prehospital blood product transfusion (PHT). We hypothesized that PHT of plasma and/or RBCs would result in improved survival after injury in patients transported by helicopter. METHODS Adult trauma patients transported by helicopter from the scene to nine Level 1 trauma centers were prospectively observed from Jan–Nov 2015. Five helicopter systems had plasma and/or RBCs while the other four helicopter systems used only crystalloid resuscitation. All patients meeting predetermined high risk criteria were analyzed. Patients receiving PHT were compared to patients not receiving PHT. Our primary analysis compared mortality at 3 hours, 24 hours, and 30 days, using logistic regression to adjust for confounders and site heterogeneity to model patients who were matched on propensity scores. RESULTS 25,118 trauma patients were admitted, 2341 (9%) were transported by helicopter, of which 1058 (45%) met the highest risk criteria. 585/1058 patients were flown on helicopters carrying blood products. In the systems with blood available, prehospital median systolic blood pressure (125 vs 128) and GCS (7 vs 14) was significantly lower, while median ISS was significantly higher (21 vs 14). Unadjusted mortality was significantly higher in the systems with blood products available, at 3 (8.4% vs 3.6%), 24 (12.6% vs 8.9%) hours and 30 days (19.3% vs 13.3%). 24% of eligible patients received a prehospital transfusion. A median of 1 unit of RBCs and plasma were transfused prehospital. Of patients receiving PHT, 24% received only plasma, 7% received only RBCs and 69% received both. In the propensity score matching analysis (n=109), PHT was not significantly associated with mortality at any time point, although only 10% of the high risk sample were able to be matched

  14. Theoretical Cognitive Principles Observed in the Social Studies Classroom

    ERIC Educational Resources Information Center

    Walker, Juan; Langan, Elise; Kemp, Andrew; Pagnotti, John; Russell, William

    2016-01-01

    Pre-service elementary social studies teachers in the south eastern United States participated in a mixed methods study to determine the degree to which they utilized critical thinking skills. Insight Assessments administered analysis of their reflections, critical thinking skills, and dispositions test. The researchers developed a post survey for…

  15. Scientific and Ethical Approaches for Observational Exposure Studies

    EPA Science Inventory

    Researchers conduct observational human exposure studies to understand how and the extent to which people come into contact with chemicals and environmental stressors in their everyday lives, through the air they breathe, the food and liquids they consume, and the things they tou...

  16. The Indiana Science Initiative: Lessons from a Classroom Observation Study

    ERIC Educational Resources Information Center

    Cook, Nicole D.; Walker, William S.; Weaver, Gabriela C.; Sorge, Brandon H.

    2015-01-01

    The Indiana Science Initiative (ISI) is a systemic effort to reform K-8 science education. The program provides teachers with professional development, reform-oriented science modules, and materials support. To examine the impact of the initiative's professional development, a participant observation study was conducted in the program's pilot…

  17. Space observations for global and regional studies of the biosphere

    NASA Technical Reports Server (NTRS)

    Cihlar, J.; Li, Z.; Chen, J.; Sellers, P.; Hall, F.

    1994-01-01

    The capability to make space-based measurements of Earth at high spatial and temporal resolutions, which would not otherwise be economically or practically feasible, became available just in time to contribute to scientific understanding of the interactive processes governing the total Earth system. Such understanding has now become essential in order to take practical steps which would counteract or mitigate the pervasive impact of the growing human population on the future habitability of the Earth. The paper reviews the rationale for using space observations for studies of climate and terrestrial ecosystems at global and regional scales, as well as the requirements for such observations for studies of climate and ecosystem dynamics. The present status of these developments is reported along with initiatives under way to advance the use of satellite observations for Earth system studies. The most important contribution of space observations is the provision of physical or biophysical parameters for models representing various components of the Earth system. Examples of such parameters are given for climatic and ecosystem studies.

  18. Observing position and movements in hydrotherapy: a pilot study.

    PubMed

    Stark, Mary Ann; Rudell, Barb; Haus, George

    2008-01-01

    To observe and describe the positions and movements women choose while immersed in water during the first stage of labor. Descriptive, observational pilot study. A rural community hospital that provided hydrotherapy in labor. Women (N = 7) who intended to use hydrotherapy in labor were recruited prenatally from a midwife-managed practice. For 15 minutes of each hour during the first stage of labor, position and movements of the participants were observed and recorded on a laptop computer. The observational tool was developed for this study from a review of the literature and interviews with nursing experts; 435 observations were recorded. Women were free to choose when and how long to use hydrotherapy and had no restriction on their positions and movements. Only 3 of the 7 participants labored in the tub. Women demonstrated a greater range of positions and movements in the tub than in bed, both throughout labor and during late first-stage labor (7-10 cm of dilatation). Women had more contractions and made more rhythmic movements while in the tub than in bed. Hydrotherapy may encourage upright positions and movements that facilitate labor progress and coping, helping women avoid unnecessary interventions.

  19. Method for determining the octane rating of gasoline samples by observing corresponding acoustic resonances therein

    DOEpatents

    Sinha, Dipen N.; Anthony, Brian W.

    1997-01-01

    A method for determining the octane rating of gasoline samples by observing corresponding acoustic resonances therein. A direct correlation between the octane rating of gasoline and the frequency of corresponding acoustic resonances therein has been experimentally observed. Therefore, the octane rating of a gasoline sample can be directly determined through speed of sound measurements instead of by the cumbersome process of quantifying the knocking quality of the gasoline. Various receptacle geometries and construction materials may be employed. Moreover, it is anticipated that the measurements can be performed on flowing samples in pipes, thereby rendering the present method useful in refineries and distilleries.

  20. Method for determining the octane rating of gasoline samples by observing corresponding acoustic resonances therein

    DOEpatents

    Sinha, D.N.; Anthony, B.W.

    1997-02-25

    A method is described for determining the octane rating of gasoline samples by observing corresponding acoustic resonances therein. A direct correlation between the octane rating of gasoline and the frequency of corresponding acoustic resonances therein has been experimentally observed. Therefore, the octane rating of a gasoline sample can be directly determined through speed of sound measurements instead of by the cumbersome process of quantifying the knocking quality of the gasoline. Various receptacle geometries and construction materials may be employed. Moreover, it is anticipated that the measurements can be performed on flowing samples in pipes, thereby rendering the present method useful in refineries and distilleries. 3 figs.

  1. Propensity Score Estimation With Boosted Regression for Evaluating Causal Effects in Observational Studies

    ERIC Educational Resources Information Center

    McCaffrey, Daniel F.; Ridgeway, Greg; Morral, Andrew R.

    2004-01-01

    Causal effect modeling with naturalistic rather than experimental data is challenging. In observational studies participants in different treatment conditions may also differ on pretreatment characteristics that influence outcomes. Propensity score methods can theoretically eliminate these confounds for all observed covariates, but accurate…

  2. A Study of the Extratropical Tropopause from Observations and Models

    NASA Astrophysics Data System (ADS)

    Wang, Shu Meir

    adequate horizontal resolution is needed to resolve the baroclinic mixing and the small-scale filamentary structures. We used many methods in this study to show that there is more baroclinic activity seen in higher horizontal resolution. We also compared the correlations of the tropopause height with three variations in different quantities (PV fluxes, the upper tropospheric vorticity, and heat fluxes), and found that the correlations of the tropopause height and PV fluxes are the highest among the three. Thus, we conclude that baroclinic mixing is the most important factor that controls the extratropical tropopause sharpness. This also explains why the extratropical tropopause is sharper at midlatitudes when higher horizontal resolution is used (see figure 2.4 in the thesis and figure 2 in Son and Polvani's (2007)) since there is more baroclinic activity in the higher horizontal resolution models. Since there is more baroclinic activity seen in higher horizontal resolution, the baroclinic eddy drag is larger, which intensifies the thermally direct cell. The stronger thermally direct cell with higher horizontal resolution has greater downward motion in higher latitudes, and thus lowers the extratropical tropopause more in higher horizontal resolution models, which explains why the extratropical tropopause is lower in higher horizontal than in lower horizontal resolution models, as in Son and Polvani's (2007) paper.

  3. Assessing the Impact of Observations on Numerical Weather Forecasts Using the Adjoint Method

    NASA Technical Reports Server (NTRS)

    Gelaro, Ronald

    2012-01-01

    The adjoint of a data assimilation system provides a flexible and efficient tool for estimating observation impacts on short-range weather forecasts. The impacts of any or all observations can be estimated simultaneously based on a single execution of the adjoint system. The results can be easily aggregated according to data type, location, channel, etc., making this technique especially attractive for examining the impacts of new hyper-spectral satellite instruments and for conducting regular, even near-real time, monitoring of the entire observing system. This talk provides a general overview of the adjoint method, including the theoretical basis and practical implementation of the technique. Results are presented from the adjoint-based observation impact monitoring tool in NASA's GEOS-5 global atmospheric data assimilation and forecast system. When performed in conjunction with standard observing system experiments (OSEs), the adjoint results reveal both redundancies and dependencies between observing system impacts as observations are added or removed from the assimilation system. Understanding these dependencies may be important for optimizing the use of the current observational network and defining requirements for future observing systems

  4. Driving performance while using cell phones: an observational study.

    PubMed

    Rosenbloom, Tova

    2006-01-01

    Through spontaneous driving observations, this study sought to examine the impact of using a hands-free cell phone while driving on speed and safe gap keeping behaviors. The study also examined the association between the measure of disturbance created by using a cell phone and the driver's awareness of the disturbance. Twenty-three male adults were observed while driving for an hour and a half each; drivers were unaware of being observed. During the session, each of the participants received a phone call, initiated by an associate of the observer. The experiment was divided into two periods during which the experimental parameters were monitored: 10 minutes during conversation on a cell phone and 10 minutes of non-conversation on a hands-free cell phone. After the experiment, the driver was questioned concerning the extent to which his/her driving was disturbed by the cell phone conversation. T-test for matched samples revealed that the gaps between the drivers' cars and those in front of them diminished when drivers were engaged in the cell phone conversations. Repeated measures ANOVA revealed that drivers that had short conversations did not change their speed, while drivers who were engaged in long (over 16 minutes) conversations drove faster. No effect of drivers' awareness toward cell phone-related disturbance on actual driving behavior monitored in the present study was found.

  5. Association between day of delivery and obstetric outcomes: observational study.

    PubMed

    Palmer, William L; Bottle, A; Aylin, P

    2015-11-24

    What is the association between day of delivery and measures of quality and safety of maternity services, particularly comparing weekend with weekday performance? This observational study examined outcomes for maternal and neonatal records (1,332,835 deliveries and 1,349,599 births between 1 April 2010 and 31 March 2012) within the nationwide administrative dataset for English National Health Service hospitals by day of the week. Groups were defined by day of admission (for maternal indicators) or delivery (for neonatal indicators) rather than by day of complication. Logistic regression was used to adjust for case mix factors including gestational age, birth weight, and maternal age. Staffing factors were also investigated using multilevel models to evaluate the association between outcomes and level of consultant presence. The primary outcomes were perinatal mortality and-for both neonate and mother-infections, emergency readmissions, and injuries. Performance across four of the seven measures was significantly worse for women admitted, and babies born, at weekends. In particular, the perinatal mortality rate was 7.3 per 1000 babies delivered at weekends, 0.9 per 1000 higher than for weekdays (adjusted odds ratio 1.07, 95% confidence interval 1.02 to 1.13). No consistent association between outcomes and staffing was identified, although trusts that complied with recommended levels of consultant presence had a perineal tear rate of 3.0% compared with 3.3% for non-compliant services (adjusted odds ratio 1.21, 1.00 to 1.45). Limitations of the analysis include the method of categorising performance temporally, which was mitigated by using a midweek reference day (Tuesday). Further research is needed to investigate possible bias from unmeasured confounders and explore the nature of the causal relationship. This study provides an evaluation of the "weekend effect" in obstetric care, covering a range of outcomes. The results would suggest approximately 770 perinatal

  6. A simple linear regression method for quantitative trait loci linkage analysis with censored observations.

    PubMed

    Anderson, Carl A; McRae, Allan F; Visscher, Peter M

    2006-07-01

    Standard quantitative trait loci (QTL) mapping techniques commonly assume that the trait is both fully observed and normally distributed. When considering survival or age-at-onset traits these assumptions are often incorrect. Methods have been developed to map QTL for survival traits; however, they are both computationally intensive and not available in standard genome analysis software packages. We propose a grouped linear regression method for the analysis of continuous survival data. Using simulation we compare this method to both the Cox and Weibull proportional hazards models and a standard linear regression method that ignores censoring. The grouped linear regression method is of equivalent power to both the Cox and Weibull proportional hazards methods and is significantly better than the standard linear regression method when censored observations are present. The method is also robust to the proportion of censored individuals and the underlying distribution of the trait. On the basis of linear regression methodology, the grouped linear regression model is computationally simple and fast and can be implemented readily in freely available statistical software.

  7. Evaluating performance of risk identification methods through a large-scale simulation of observational data.

    PubMed

    Ryan, Patrick B; Schuemie, Martijn J

    2013-10-01

    There has been only limited evaluation of statistical methods for identifying safety risks of drug exposure in observational healthcare data. Simulations can support empirical evaluation, but have not been shown to adequately model the real-world phenomena that challenge observational analyses. To design and evaluate a probabilistic framework (OSIM2) for generating simulated observational healthcare data, and to use this data for evaluating the performance of methods in identifying associations between drug exposure and health outcomes of interest. Seven observational designs, including case-control, cohort, self-controlled case series, and self-controlled cohort design were applied to 399 drug-outcome scenarios in 6 simulated datasets with no effect and injected relative risks of 1.25, 1.5, 2, 4, and 10, respectively. Longitudinal data for 10 million simulated patients were generated using a model derived from an administrative claims database, with associated demographics, periods of drug exposure derived from pharmacy dispensings, and medical conditions derived from diagnoses on medical claims. Simulation validation was performed through descriptive comparison with real source data. Method performance was evaluated using Area Under ROC Curve (AUC), bias, and mean squared error. OSIM2 replicates prevalence and types of confounding observed in real claims data. When simulated data are injected with relative risks (RR) ≥ 2, all designs have good predictive accuracy (AUC > 0.90), but when RR < 2, no methods achieve 100 % predictions. Each method exhibits a different bias profile, which changes with the effect size. OSIM2 can support methodological research. Results from simulation suggest method operating characteristics are far from nominal properties.

  8. AMR Studies of Star Formation: Simulations and Simulated Observations

    NASA Astrophysics Data System (ADS)

    Offner, Stella; McKee, C. F.; Klein, R. I.

    2009-01-01

    Molecular clouds are typically observed to be approximately virialized with gravitational and turbulent energy in balance, yielding a star formation rate of a few percent. The origin and characteristics of the observed supersonic turbulence are poorly understood, and without continued energy injection the turbulence is predicted to decay within a cloud dynamical time. Recent observations and analytic work have suggested a strong connection between the initial stellar mass function, the core mass function, and turbulence characteristics. The role of magnetic fields in determining core lifetimes, shapes, and kinematic properties remains hotly debated. Simulations are a formidable tool for studying the complex process of star formation and addressing these puzzles. I present my results modeling low-mass star formation using the ORION adaptive mesh refinement (AMR) code. I investigate the properties of forming cores and protostars in simulations in which the turbulence is driven to maintain virial balance and where it is allowed to decay. I will discuss simulated observations of cores in dust emission and in molecular tracers and compare to observations of local star-forming clouds. I will also present results from ORION cluster simulations including flux-limited diffusion radiative transfer and show that radiative feedback, even from low-mass stars, has a significant effect on core fragmentation, disk properties, and the IMF. Finally, I will discuss the new simulation frontier of AMR multigroup radiative transfer.

  9. Effects of observers using different methods upon the total population estimates of two resident island birds

    Treesearch

    Sheila Conant; Mark S. Collins; C. John Ralph

    1981-01-01

    During a 5-week study of the Nihoa Millerbird and Nihoa Finch, we censused birds using these techniques: two line transect methods, a variable-distance circular plot method, and spot-mapping of territories (millerbirds only). Densities derived from these methods varied greatly. Due to differences in behavior, it appeared that the two species reacted differently to the...

  10. The reporting of observational research studies in dermatology journals: a literature-based study.

    PubMed

    Langan, Sinéad; Schmitt, Jochen; Coenraads, Pieter-Jan; Svensson, Ake; von Elm, Erik; Williams, Hywel

    2010-05-01

    To assess the quality of reporting in observational studies in dermatology. Five dermatology journals-the Archives of Dermatology, the British Journal of Dermatology, the Journal of the American Academy of Dermatology, the Journal of Investigative Dermatology, and Acta Dermato-Venereologica. Cohort, case-control, and cross-sectional studies published as original articles during the period January 2005 through December 2007. Studies were identified with a literature search of PubMed combining the journal title and the term epidemiological studies (free text) and by hand searching all of the issues of each journal to identify relevant articles. All articles were extracted by 2 reviewers independently using standardized checklists based on the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) recommendations. The number and proportion of reported STROBE items were analyzed for each article. The proportion of studies with good reporting for each item was also assessed. A total of 138 articles were included and analyzed. Reporting quality was very mixed. Key areas that were infrequently reported included sample size calculations (n = 10 [7%]), missing data (n = 8 [6%]), losses to follow-up (n = 17 [12%]), and statistical methods (n = 19 [14%]). Only 13 studies (9%) explained the role of funders in the research. The quality of reporting was similar across study designs for "critical" questions with the exception of reporting of participant details, which was better reported in cohort studies (96%) compared with cross-sectional (80%) and case-control (70%) studies. It is difficult to judge the quality of dermatological research unless it is reported well. This study has identified a clear need to improve the quality of reporting of observational studies in dermatology. We recommend that dermatology journals adopt the STROBE criteria.

  11. Intrinsic nonlinearity and method of disturbed observations in inverse problems of celestial mechanics

    NASA Astrophysics Data System (ADS)

    Avdyushev, Victor A.

    2017-12-01

    Orbit determination from a small sample of observations over a very short observed orbital arc is a strongly nonlinear inverse problem. In such problems an evaluation of orbital uncertainty due to random observation errors is greatly complicated, since linear estimations conventionally used are no longer acceptable for describing the uncertainty even as a rough approximation. Nevertheless, if an inverse problem is weakly intrinsically nonlinear, then one can resort to the so-called method of disturbed observations (aka observational Monte Carlo). Previously, we showed that the weaker the intrinsic nonlinearity, the more efficient the method, i.e. the more accurate it enables one to simulate stochastically the orbital uncertainty, while it is strictly exact only when the problem is intrinsically linear. However, as we ascertained experimentally, its efficiency was found to be higher than that of other stochastic methods widely applied in practice. In the present paper we investigate the intrinsic nonlinearity in complicated inverse problems of Celestial Mechanics when orbits are determined from little informative samples of observations, which typically occurs for recently discovered asteroids. To inquire into the question, we introduce an index of intrinsic nonlinearity. In asteroid problems it evinces that the intrinsic nonlinearity can be strong enough to affect appreciably probabilistic estimates, especially at the very short observed orbital arcs that the asteroids travel on for about a hundredth of their orbital periods and less. As it is known from regression analysis, the source of intrinsic nonlinearity is the nonflatness of the estimation subspace specified by a dynamical model in the observation space. Our numerical results indicate that when determining asteroid orbits it is actually very slight. However, in the parametric space the effect of intrinsic nonlinearity is exaggerated mainly by the ill-conditioning of the inverse problem. Even so, as for the

  12. Continuing Studies in Support of Ultraviolet Observations of Planetary Atmospheres

    NASA Technical Reports Server (NTRS)

    Clark, John

    1997-01-01

    This program was a one-year extension of an earlier Planetary Atmospheres program grant, covering the period 1 August 1996 through 30 September 1997. The grant was for supporting work to complement an active program observing planetary atmospheres with Earth-orbital telescopes, principally the Hubble Space Telescope (HST). The recent concentration of this work has been on HST observations of Jupiter's upper atmosphere and aurora, but it has also included observations of Io, serendipitous observations of asteroids, and observations of the velocity structure in the interplanetary medium. The observations of Jupiter have been at vacuum ultraviolet wavelengths, including imaging and spectroscopy of the auroral and airglow emissions. The most recent HST observations have been at the same time as in situ measurements made by the Galileo orbiter instruments, as reflected in the meeting presentations listed below. Concentrated efforts have been applied in this year to the following projects: The analysis of HST WFPC 2 images of Jupiter's aurora, including the Io footprint emissions. We have performed a comparative analysis of the lo footprint locations with two magnetic field models, studied the statistical properties of the apparent dawn auroral storms on Jupiter, and found various other repeated patterns in Jupiter's aurora. Analysis and modeling of airglow and auroral Ly alpha emission line profiles from Jupiter. This has included modeling the aurora] line profiles, including the energy degradation of precipitating charged particles and radiative transfer of the emerging emissions. Jupiter's auroral emission line profile is self-absorbed, since it is produced by an internal source, and the resulting emission with a deep central absorption from the overlying atmosphere permits modeling of the depth of the emissions, plus the motion of the emitting layer with respect to the overlying atmospheric column from the observed Doppler shift of the central absorption. By contrast

  13. Outcomes from massive paracetamol overdose: a retrospective observational study

    PubMed Central

    Marks, Daniel J. B.; Dargan, Paul I.; Archer, John R. H.; Davies, Charlotte L.; Dines, Alison M.; Wood, David M.

    2017-01-01

    LINKED ARTICLE This article is commented on by Bateman DN and Dear JW. Should we treat very large paracetamol overdose differently? Br J Clin Pharmacol 2017; 83: 1163–5. https://doi.org/10.1111/bcp.13279 Aims Treatment of paracetamol (acetaminophen) overdose with acetylcysteine is standardized, with dose determined only by patient weight. The validity of this approach for massive overdoses has been questioned. We systematically compared outcomes in massive and non‐massive overdoses, to guide whether alternative treatment strategies should be considered, and whether the ratio between measured timed paracetamol concentrations (APAPpl) and treatment nomogram thresholds at those time points (APAPt) provides a useful assessment tool. Methods This is a retrospective observational study of all patients (n = 545) between 2005 and 2013 admitted to a tertiary care toxicology service with acute non‐staggered paracetamol overdose. Massive overdoses were defined as extrapolated 4‐h plasma paracetamol concentrations >250 mg l−1, or reported ingestions ≥30 g. Outcomes (liver injury, coagulopathy and kidney injury) were assessed in relation to reported dose and APAPpl:APAPt ratio (based on a treatment line through 100 mg l−1 at 4 h), and time to acetylcysteine. Results Ingestions of ≥30 g paracetamol correlated with higher peak serum aminotransferase (r = 0.212, P < 0.0001) and creatinine (r = 0.138, P = 0.002) concentrations. Acute liver injury, hepatotoxicity and coagulopathy were more frequent with APAPpl:APAPt ≥ 3 with odds ratios (OR) and 95% confidence intervals (CI) of 9.19 (5.04–16.68), 35.95 (8.80–158.1) and 8.34 (4.43–15.84), respectively (P < 0.0001). Heightened risk persisted in patients receiving acetylcysteine within 8 h of overdose. Conclusion Patients presenting following massive paracetamol overdose are at higher risk of organ injury, even when acetylcysteine is administered early. Enhanced therapeutic strategies

  14. Corneal permeability changes in dry eye disease: an observational study.

    PubMed

    Fujitani, Kenji; Gadaria, Neha; Lee, Kyu-In; Barry, Brendan; Asbell, Penny

    2016-05-13

    Diagnostic tests for dry eye disease (DED), including ocular surface disease index (OSDI), tear breakup time (TBUT), corneal fluorescein staining, and lissamine staining, have great deal of variability. We investigated whether fluorophotometry correlated with previously established DED diagnostic tests and whether it could serve as a novel objective metric to evaluate DED. Dry eye patients who have had established signs or symptoms for at least 6 months were included in this observational study. Normal subjects with no symptoms of dry eyes served as controls. Each eye had a baseline fluorescein scan prior to any fluorescein dye. Fluorescein dye was then placed into both eyes, rinsed with saline solution, and scanned at 5, 10, 15, and 30 min. Patients were administered the following diagnostic tests to correlate with fluorophotometry: OSDI, TBUT, fluorescein, and lissamine. Standard protocols were used. P < 0.05 was considered significant. Fifty eyes from 25 patients (DED = 22 eyes, 11 patients; Normal = 28 eyes, 14 patients) were included. Baseline scans of the dry eye and control groups did not show any statistical difference (p = 0.84). Fluorescein concentration of DED and normal patients showed statistical significance at all time intervals (p < 10(-5), 0.001, 0.002, 0.049 for 5, 10, 15, & 30 min respectively). Fluorophotometry values converged towards baseline as time elapsed, but both groups were still statistically different at 30 min (p < 0.01). We used four fluorophotometry scoring methods and correlated them with OSDI, TBUT, fluorescein, and lissamine along with adjusted and aggregate scores. The four scoring schemes did not show any significant correlations with the other tests, except for correlations seen with lissamine and 10 (p = 0.045, 0.034) and 15 min (p = 0.013, 0.012), and with aggregate scores and 15 min (p = 0.042, 0.017). Fluorophotometry generally did not correlate with any other DED tests, even

  15. A new method to evaluate image quality of CBCT images quantitatively without observers

    PubMed Central

    Shimizu, Mayumi; Okamura, Kazutoshi; Yoshida, Shoko; Weerawanich, Warangkana; Tokumori, Kenji; Jasa, Gainer R; Yoshiura, Kazunori

    2017-01-01

    Objectives: To develop an observer-free method for quantitatively evaluating the image quality of CBCT images by applying just-noticeable difference (JND). Methods: We used two test objects: (1) a Teflon (polytetrafluoroethylene) plate phantom attached to a dry human mandible; and (2) a block phantom consisting of a Teflon step phantom and an aluminium step phantom. These phantoms had holes with different depths. They were immersed in water and scanned with a CB MercuRay (Hitachi Medical Corporation, Tokyo, Japan) at tube voltages of 120 kV, 100 kV, 80 kV and 60 kV. Superimposed images of the phantoms with holes were used for evaluation. The number of detectable holes was used as an index of image quality. In detecting holes quantitatively, the threshold grey value (ΔG), which differentiated holes from the background, was calculated using a specific threshold (the JND), and we extracted the holes with grey values above ΔG. The indices obtained by this quantitative method (the extracted hole values) were compared with the observer evaluations (the observed hole values). In addition, the contrast-to-noise ratio (CNR) of the shallowest detectable holes and the deepest undetectable holes were measured to evaluate the contribution of CNR to detectability. Results: The results of this evaluation method corresponded almost exactly with the evaluations made by observers. The extracted hole values reflected the influence of different tube voltages. All extracted holes had an area with a CNR of ≥1.5. Conclusions: This quantitative method of evaluating CBCT image quality may be more useful and less time-consuming than evaluation by observation. PMID:28045343

  16. Interference data correction methods for lunar observation with a large-aperture static imaging spectrometer.

    PubMed

    Zhang, Geng; Wang, Shuang; Li, Libo; Hu, Xiuqing; Hu, Bingliang

    2016-11-01

    The lunar spectrum has been used in radiometric calibration and sensor stability monitoring for spaceborne optical sensors. A ground-based large-aperture static image spectrometer (LASIS) can be used to acquire the lunar spectral image for lunar radiance model improvement when the moon orbits over its viewing field. The lunar orbiting behavior is not consistent with the desired scanning speed and direction of LASIS. To correctly extract interferograms from the obtained data, a translation correction method based on image correlation is proposed. This method registers the frames to a reference frame to reduce accumulative errors. Furthermore, we propose a circle-matching-based approach to achieve even higher accuracy during observation of the full moon. To demonstrate the effectiveness of our approaches, experiments are run on true lunar observation data. The results show that the proposed approaches outperform the state-of-the-art methods.

  17. Strategies GeoCape Intelligent Observation Studies @ GSFC

    NASA Technical Reports Server (NTRS)

    Cappelaere, Pat; Frye, Stu; Moe, Karen; Mandl, Dan; LeMoigne, Jacqueline; Flatley, Tom; Geist, Alessandro

    2015-01-01

    This presentation provides information a summary of the tradeoff studies conducted for GeoCape by the GSFC team in terms of how to optimize GeoCape observation efficiency. Tradeoffs include total ground scheduling with simple priorities, ground scheduling with cloud forecast, ground scheduling with sub-area forecast, onboard scheduling with onboard cloud detection and smart onboard scheduling and onboard image processing. The tradeoffs considered optimzing cost, downlink bandwidth and total number of images acquired.

  18. Observational Study of Human Electrical Muscle Incapacitation and Cardiac Effects

    DTIC Science & Technology

    2016-05-01

    the American College of Cardiology Foundation. Circulation. 2010 Mar 2; 121(8):1047-1060. 12. U.S. Department of Health and Human Services, Food and...AFRL-RH-FS-TR-2016-0010 Observational Study of Human Electrical Muscle Incapacitation and Cardiac Effects John A. Gibbons Brian B. Lupfer Alan...Ashworth Human Effectiveness Directorate Bioeffects Division Andrew J. Mojica KBRwyle Inc. Mark E. Peele USARMY MEDCOM Brooke Army Medical Center

  19. Folic acid supplementation and preterm birth: results from observational studies.

    PubMed

    Mantovani, Elena; Filippini, Francesca; Bortolus, Renata; Franchi, Massimo

    2014-01-01

    Folic acid (FA) supplementation is recommended worldwide in the periconceptional period for the prevention of neural tube defects. Due to its involvement in a number of cellular processes, its role in other pregnancy outcomes such as miscarriage, recurrent miscarriage, low birth weight, preterm birth (PTB), preeclampsia, abruptio placentae, and stillbirth has been investigated. PTB is a leading cause of perinatal mortality and morbidity; therefore its association with FA supplementation is of major interest. The analysis of a small number of randomized clinical trials (RCTs) has not found a beneficial role of FA in reducing the rate of PTBs. The aim of this review was to examine the results from recent observational studies about the effect of FA supplementation on PTB. We carried out a search on Medline and by manual search of the observational studies from 2009 onwards that analyzed the rate of PTB in patients who received supplementation with FA before and/or throughout pregnancy. The results from recent observational studies suggest a slight reduction of PTBs that is not consistent with the results from RCTs. Further research is needed to better understand the role of FA supplementation before and during pregnancy in PTB.

  20. Assessing distractors and teamwork during surgery: developing an event-based method for direct observation.

    PubMed

    Seelandt, Julia C; Tschan, Franziska; Keller, Sandra; Beldi, Guido; Jenni, Nadja; Kurmann, Anita; Candinas, Daniel; Semmer, Norbert K

    2014-11-01

    To develop a behavioural observation method to simultaneously assess distractors and communication/teamwork during surgical procedures through direct, on-site observations; to establish the reliability of the method for long (>3 h) procedures. Observational categories for an event-based coding system were developed based on expert interviews, observations and a literature review. Using Cohen's κ and the intraclass correlation coefficient, interobserver agreement was assessed for 29 procedures. Agreement was calculated for the entire surgery, and for the 1st hour. In addition, interobserver agreement was assessed between two tired observers and between a tired and a non-tired observer after 3 h of surgery. The observational system has five codes for distractors (door openings, noise distractors, technical distractors, side conversations and interruptions), eight codes for communication/teamwork (case-relevant communication, teaching, leadership, problem solving, case-irrelevant communication, laughter, tension and communication with external visitors) and five contextual codes (incision, last stitch, personnel changes in the sterile team, location changes around the table and incidents). Based on 5-min intervals, Cohen's κ was good to excellent for distractors (0.74-0.98) and for communication/teamwork (0.70-1). Based on frequency counts, intraclass correlation coefficient was excellent for distractors (0.86-0.99) and good to excellent for communication/teamwork (0.45-0.99). After 3 h of surgery, Cohen's κ was 0.78-0.93 for distractors, and 0.79-1 for communication/teamwork. The observational method developed allows a single observer to simultaneously assess distractors and communication/teamwork. Even for long procedures, high interobserver agreement can be achieved. Data collected with this method allow for investigating separate or combined effects of distractions and communication/teamwork on surgical performance and patient outcomes. Published by the

  1. Comparison of Observation Impacts in Two Forecast Systems using Adjoint Methods

    NASA Technical Reports Server (NTRS)

    Gelaro, Ronald; Langland, Rolf; Todling, Ricardo

    2009-01-01

    An experiment is being conducted to compare directly the impact of all assimilated observations on short-range forecast errors in different operational forecast systems. We use the adjoint-based method developed by Langland and Baker (2004), which allows these impacts to be efficiently calculated. This presentation describes preliminary results for a "baseline" set of observations, including both satellite radiances and conventional observations, used by the Navy/NOGAPS and NASA/GEOS-5 forecast systems for the month of January 2007. In each system, about 65% of the total reduction in 24-h forecast error is provided by satellite observations, although the impact of rawinsonde, aircraft, land, and ship-based observations remains significant. Only a small majority (50- 55%) of all observations assimilated improves the forecast, while the rest degrade it. It is found that most of the total forecast error reduction comes from observations with moderate-size innovations providing small to moderate impacts, not from outliers with very large positive or negative innovations. In a global context, the relative impacts of the major observation types are fairly similar in each system, although regional differences in observation impact can be significant. Of particular interest is the fact that while satellite radiances have a large positive impact overall, they degrade the forecast in certain locations common to both systems, especially over land and ice surfaces. Ongoing comparisons of this type, with results expected from other operational centers, should lead to more robust conclusions about the impacts of the various components of the observing system as well as about the strengths and weaknesses of the methodologies used to assimilate them.

  2. Tropospheric Chemistry Studies using Observations from GOME and TOMS

    NASA Technical Reports Server (NTRS)

    Chance, Kelly; Spurr, Robert J. D.; Kurosu, Thomas P.; Jacob, Daniel J.; Gleason, James F.

    2003-01-01

    Studies to quantitatively determine trace gas and aerosol amounts from the Global Ozone Monitoring Experiment (GOME) and the Total Ozone Monitoring Experiment (TOMS) and to perform chemical modeling studies which utilize these results are given. This includes: 1. Analysis of measurements from the GOME and TOMS instruments for troposphere distributions of O3 and HCHO; troposphere enhancements of SO2, NO2 and aerosols associated with major sources; and springtime events of elevated BrO in the lower Arctic troposphere. 2. Application of a global 3-dimensional model of troposphere chemistry to interpret the GOME observations in terms of the factors controlling the abundances of troposphere ozone and OH.

  3. Using data mining techniques to characterize participation in observational studies.

    PubMed

    Linden, Ariel; Yarnold, Paul R

    2016-12-01

    Data mining techniques are gaining in popularity among health researchers for an array of purposes, such as improving diagnostic accuracy, identifying high-risk patients and extracting concepts from unstructured data. In this paper, we describe how these techniques can be applied to another area in the health research domain: identifying characteristics of individuals who do and do not choose to participate in observational studies. In contrast to randomized studies where individuals have no control over their treatment assignment, participants in observational studies self-select into the treatment arm and therefore have the potential to differ in their characteristics from those who elect not to participate. These differences may explain part, or all, of the difference in the observed outcome, making it crucial to assess whether there is differential participation based on observed characteristics. As compared to traditional approaches to this assessment, data mining offers a more precise understanding of these differences. To describe and illustrate the application of data mining in this domain, we use data from a primary care-based medical home pilot programme and compare the performance of commonly used classification approaches - logistic regression, support vector machines, random forests and classification tree analysis (CTA) - in correctly classifying participants and non-participants. We find that CTA is substantially more accurate than the other models. Moreover, unlike the other models, CTA offers transparency in its computational approach, ease of interpretation via the decision rules produced and provides statistical results familiar to health researchers. Beyond their application to research, data mining techniques could help administrators to identify new candidates for participation who may most benefit from the intervention. © 2016 John Wiley & Sons, Ltd.

  4. Theory, Method, and Triangulation in the Study of Street Children.

    ERIC Educational Resources Information Center

    Lucchini, Riccardo

    1996-01-01

    Describes how a comparative study of street children in Montevideo (Uruguay), Rio de Janeiro, and Mexico City contributes to a synergism between theory and method. Notes how theoretical approaches of symbolic interactionism, genetic structuralism, and habitus theory complement interview, participant observation, and content analysis methods;…

  5. The Asthma Mobile Health Study, a large-scale clinical observational study using ResearchKit.

    PubMed

    Chan, Yu-Feng Yvonne; Wang, Pei; Rogers, Linda; Tignor, Nicole; Zweig, Micol; Hershman, Steven G; Genes, Nicholas; Scott, Erick R; Krock, Eric; Badgeley, Marcus; Edgar, Ron; Violante, Samantha; Wright, Rosalind; Powell, Charles A; Dudley, Joel T; Schadt, Eric E

    2017-04-01

    The feasibility of using mobile health applications to conduct observational clinical studies requires rigorous validation. Here, we report initial findings from the Asthma Mobile Health Study, a research study, including recruitment, consent, and enrollment, conducted entirely remotely by smartphone. We achieved secure bidirectional data flow between investigators and 7,593 participants from across the United States, including many with severe asthma. Our platform enabled prospective collection of longitudinal, multidimensional data (e.g., surveys, devices, geolocation, and air quality) in a subset of users over the 6-month study period. Consistent trending and correlation of interrelated variables support the quality of data obtained via this method. We detected increased reporting of asthma symptoms in regions affected by heat, pollen, and wildfires. Potential challenges with this technology include selection bias, low retention rates, reporting bias, and data security. These issues require attention to realize the full potential of mobile platforms in research and patient care.

  6. The Asthma Mobile Health Study, a large-scale clinical observational study using ResearchKit

    PubMed Central

    Chan, Yu-Feng Yvonne; Wang, Pei; Rogers, Linda; Tignor, Nicole; Zweig, Micol; Hershman, Steven G; Genes, Nicholas; Scott, Erick R; Krock, Eric; Badgeley, Marcus; Edgar, Ron; Violante, Samantha; Wright, Rosalind; Powell, Charles A; Dudley, Joel T; Schadt, Eric E

    2017-01-01

    The feasibility of using mobile health applications to conduct observational clinical studies requires rigorous validation. Here, we report initial findings from the Asthma Mobile Health Study, a research study, including recruitment, consent, and enrollment, conducted entirely remotely by smartphone. We achieved secure bidirectional data flow between investigators and 7,593 participants from across the United States, including many with severe asthma. Our platform enabled prospective collection of longitudinal, multidimensional data (e.g., surveys, devices, geolocation, and air quality) in a subset of users over the 6-month study period. Consistent trending and correlation of interrelated variables support the quality of data obtained via this method. We detected increased reporting of asthma symptoms in regions affected by heat, pollen, and wildfires. Potential challenges with this technology include selection bias, low retention rates, reporting bias, and data security. These issues require attention to realize the full potential of mobile platforms in research and patient care. PMID:28288104

  7. Forecasting Juno Microwave Radiometer Observations of Jupiter's Synchrotron Emission from Data Reconstruction Methods and Theoretical Model

    NASA Astrophysics Data System (ADS)

    Santos-Costa, D.; Bolton, S. J.; Adumitroaie, V.; Janssen, M.; Levin, S.; Sault, R. J.; De Pater, I.; Tao, C.

    2015-12-01

    The Juno spacecraft will go into polar orbit after it arrives at Jupiter in mid-2016. Between November 2016 and March 2017, six MicroWave Radiometers will collect information on Jupiter's atmosphere and electron belt. Here we present simulations of MWR observations of the electron belt synchrotron emission, and discuss the features and dynamical behavior of this emission when observations are carried out from inside the radiation zone. We first present our computation method. We combine a three-dimensional tomographic reconstruction method of Earth-based observations and a theoretical model of Jupiter's electron belt to constrain the calculations of the volume emissivity of the synchrotron radiation for any frequency, location in the Jovian inner magnetosphere (radial distance < 4 Rj), and observational direction. Values of the computed emissivity are incorporated into a synchrotron simulator to predict Juno MWR measurements (full sky maps and temperatures) at any time of the mission. Samples of simulated MWR observations are presented and examined for different segments of Juno trajectory. We also present results of our ongoing investigation of the radiation zone distribution around the planet and the sources of variation on different time-scales. We show that a better understanding of the spatial distribution and variability of the electron belt is key to realistically forecast Juno MWR measurements.

  8. Analytic Perturbation Method for Estimating Ground Flash Fraction from Satellite Lightning Observations

    NASA Technical Reports Server (NTRS)

    Koshak, William; Solakiewicz, Richard

    2013-01-01

    An analytic perturbation method is introduced for estimating the lightning ground flash fraction in a set of N lightning flashes observed by a satellite lightning mapper. The value of N is large, typically in the thousands, and the observations consist of the maximum optical group area produced by each flash. The method is tested using simulated observations that are based on Optical Transient Detector (OTD) and Lightning Imaging Sensor (LIS) data. National Lightning Detection NetworkTM (NLDN) data is used to determine the flash-type (ground or cloud) of the satellite-observed flashes, and provides the ground flash fraction truth for the simulation runs. It is found that the mean ground flash fraction retrieval errors are below 0.04 across the full range 0-1 under certain simulation conditions. In general, it is demonstrated that the retrieval errors depend on many factors (i.e., the number, N, of satellite observations, the magnitude of random and systematic measurement errors, and the number of samples used to form certain climate distributions employed in the model).

  9. Parental behaviour in paediatric chronic pain: a qualitative observational study.

    PubMed

    Dunford, Emma; Thompson, Miles; Gauntlett-Gilbert, Jeremy

    2014-10-01

    Parental behaviour appears to influence the adjustment of children with chronic pain. However, research in this area has failed to produce consistent evidence. Studies have tended to rely on self-report measures derived from adult pain populations. This qualitative, observational research provides descriptive data of parental behaviour in a clinical environment. A qualitative observational study was made of parents and adolescents in a physically stressful setting. Modified grounded theory was used to analyse verbal and non-verbal behaviours. Eight parent-adolescent dyads seeking treatment for chronic pain were videoed during physical exercise sessions. Verbal and non-verbal behaviours were recorded and transcribed. Four overarching categories emerged: 'monitoring', 'protecting', 'encouraging' and 'instructing'. These often had both verbal and non-verbal aspects. Within these categories, more precise behavioural groups were also identified. This research identifies categories of parental behaviour that were derived directly from observation, rather than imposed on the basis of results from different populations. Four categories of behaviour were derived, which clarify and extend dimensions used in existing self-report instruments. Careful description of parental behaviours showed features that past research has neglected, and highlighted potential drawbacks of apparently positive parental actions. © The Author(s) 2013.

  10. Monte-Carlo Method Application for Precising Meteor Velocity from TV Observations

    NASA Astrophysics Data System (ADS)

    Kozak, P.

    2014-12-01

    Monte-Carlo method (method of statistical trials) as an application for meteor observations processing was developed in author's Ph.D. thesis in 2005 and first used in his works in 2008. The idea of using the method consists in that if we generate random values of input data - equatorial coordinates of the meteor head in a sequence of TV frames - in accordance with their statistical distributions we get a possibility to plot the probability density distributions for all its kinematical parameters, and to obtain their mean values and dispersions. At that the theoretical possibility appears to precise the most important parameter - geocentric velocity of a meteor - which has the highest influence onto precision of meteor heliocentric orbit elements calculation. In classical approach the velocity vector was calculated in two stages: first we calculate the vector direction as a vector multiplication of vectors of poles of meteor trajectory big circles, calculated from two observational points. Then we calculated the absolute value of velocity independently from each observational point selecting any of them from some reasons as a final parameter. In the given method we propose to obtain a statistical distribution of velocity absolute value as an intersection of two distributions corresponding to velocity values obtained from different points. We suppose that such an approach has to substantially increase the precision of meteor velocity calculation and remove any subjective inaccuracies.

  11. A review of the use of a systematic observation method in coaching research between 1997 and 2016.

    PubMed

    Cope, Ed; Partington, Mark; Harvey, Stephen

    2017-10-01

    A systematic observation method has been one of the most popularly employed methods in coaching research. Kahan's review of this method conducted between 1975 and 1997 highlighted the key trends in this research, and offered methodological guidance for researchers wishing to use this method in their research. The purpose of this review was to provide an update of the use of a systematic observation method in coaching research and assess the extent to which the calls made by Kahan have been addressed. While in some respect this field of study has progressed (i.e., the introduction of qualitative methods), researchers adopting this method have failed to attend to many of the issues Kahan raised. For this method to continue to make a positive contribution towards the coaching research literature, researchers need to more critically reflect on how and why they are employing this method. At present, some of the decisions made by researchers who have conducted work in this area are not justified with a rationale. It is our intention that this review will serve as guidance for researchers and practitioners, and editors and reviewers of journals when attempting to assess the quality of this type of work.

  12. The Cystic Fibrosis Foundation Patient Registry. Design and Methods of a National Observational Disease Registry.

    PubMed

    Knapp, Emily A; Fink, Aliza K; Goss, Christopher H; Sewall, Ase; Ostrenga, Josh; Dowd, Christopher; Elbert, Alexander; Petren, Kristofer M; Marshall, Bruce C

    2016-07-01

    The Cystic Fibrosis Foundation Patient Registry (CFFPR) is an ongoing patient registry study that collects longitudinal demographic, clinical, and treatment information about persons with cystic fibrosis (CF) in the United States. CF is a life-shortening genetic disorder that occurs in approximately 1 in 3,500 births in the United States. High-quality observational data is important for clinical research, quality improvement, and clinical management. To describe the data collection, patient population, and key limitations of the CFFPR. Inclusion criteria for the CFFPR include diagnosis with CF or a CFTR-associated disorder, care at an accredited care center program, and provision of informed consent. Data from clinic visits and hospitalizations are collected through a secure website. Loss to follow-up and generalizability were examined using several methods. The accuracy of CFFPR data was evaluated with an audit of 2012 CFFPR data compared to the medical record. Since 1986, the CFFPR contains the records of 48,463 individuals with CF. Participation among individuals seen at accredited care centers is high, and loss to follow-up is low. An audit of 2012 CFFPR data suggests that the CFFPR contains 95% of clinic visits and 90% of hospitalizations found in the medical record for these patients, and nearly all of the audited fields were highly accurate. Registries such as the CFFPR are important tools for research, clinical care, and tracking incidence, mortality and population trends.

  13. Comparison of Columnar Water Vapor Measurements During The Fall 1997 ARM Intensive Observation Period: Optical Methods

    NASA Technical Reports Server (NTRS)

    Schmid, Beat; Michalsky, J.; Slater, D.; Barnard, J.; Halthore, R.; Liljegren, J.; Holben, B.; Eck, T.; Livingston, J.; Russell, P.; hide

    2000-01-01

    In the fall of 1997 the Atmospheric Radiation Measurement (ARM program conducted an intensive Observation Period (IOP) to study water vapor at its Southern Great Plains (SGP) site. Among the large number of instruments, four sun-tracking radiometers were present to measure the columnar water vapor (CWV). All four solar radiometers retrieve CWV by measuring solar transmittance in the 0.94-micrometer water vapor absorption band. As one of the steps in the CWV retrievals the aerosol component is subtracted from the total transmittance, in the 0.94-micrometer band. The aerosol optical depth comparisons among the same four radiometers are presented elsewhere. We have used three different methods to retrieve CWV. Without attempting to standardize on the same radiative transfer model and its underlying water vapor spectroscopy we found the CWV to agree within 0.13 cm (rms) for CWV values ranging from 1 to 5 cm. Preliminary results obtained when using the same updated radiative transfer model with updated spectroscopy for all instruments will also be shown. Comparisons to the microwave radiometer results will be included in the comparisons.

  14. Observational studies in systematic [corrected] reviews of comparative effectiveness: AHRQ and the Effective Health Care Program.

    PubMed

    Norris, Susan L; Atkins, David; Bruening, Wendy; Fox, Steven; Johnson, Eric; Kane, Robert; Morton, Sally C; Oremus, Mark; Ospina, Maria; Randhawa, Gurvaneet; Schoelles, Karen; Shekelle, Paul; Viswanathan, Meera

    2011-11-01

    Systematic reviewers disagree about the ability of observational studies to answer questions about the benefits or intended effects of pharmacotherapeutic, device, or procedural interventions. This study provides a framework for decision making on the inclusion of observational studies to assess benefits and intended effects in comparative effectiveness reviews (CERs). The conceptual model and recommendations were developed using a consensus process by members of the methods workgroup of the Effective Health Care Program of the Agency for Healthcare Research and Quality. In considering whether to use observational studies in CERs for addressing beneficial effects, reviewers should answer two questions: (1) Are there gaps in the evidence from randomized controlled trials (RCTs)? (2) Will observational studies provide valid and useful information? The latter question involves the following: (a) refocusing the study questions on gaps in the evidence from RCTs, (b) assessing the risk of bias of the body of evidence of observational studies, and (c) assessing whether available observational studies address the gap review questions. Because it is unusual to find sufficient evidence from RCTs to answer all key questions concerning benefit or the balance of benefits and harms, comparative effectiveness reviewers should routinely assess the appropriateness of inclusion of observational studies for questions of benefit. Furthermore, reviewers should explicitly state the rationale for inclusion or exclusion of observational studies when conducting CERs. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. Photographic zenith tube of the Zvenigorod INASAN Observatory - Processing method and observation results

    NASA Astrophysics Data System (ADS)

    Yurov, E. A.

    1992-10-01

    A method for the reduction of PZT plates which has been used at the Zvenigorod INASAN Observatory since 1986 is described. The formulas used for computing the coordinates of the stellar image in the focal plane at the midpoint of the exposure are correct to 0.0024 arcsec. Observations from February 1986 to October 1988 are compared with data of BIH and IERS, and the results of the comparison are used to compute the amplitudes of the annual terms of nonpolar variations in the observed latitudes and Delta(UTI).

  16. [A systematic social observation tool: methods and results of inter-rater reliability].

    PubMed

    Freitas, Eulilian Dias de; Camargos, Vitor Passos; Xavier, César Coelho; Caiaffa, Waleska Teixeira; Proietti, Fernando Augusto

    2013-10-01

    Systematic social observation has been used as a health research methodology for collecting information from the neighborhood physical and social environment. The objectives of this article were to describe the operationalization of direct observation of the physical and social environment in urban areas and to evaluate the instrument's reliability. The systematic social observation instrument was designed to collect information in several domains. A total of 1,306 street segments belonging to 149 different neighborhoods in Belo Horizonte, Minas Gerais, Brazil, were observed. For the reliability study, 149 segments (1 per neighborhood) were re-audited, and Fleiss kappa was used to access inter-rater agreement. Mean agreement was 0.57 (SD = 0.24); 53% had substantial or almost perfect agreement, and 20.4%, moderate agreement. The instrument appears to be appropriate for observing neighborhood characteristics that are not time-dependent, especially urban services, property characterization, pedestrian environment, and security.

  17. Observational studies of regions of massive star formation

    NASA Astrophysics Data System (ADS)

    Cooper, Heather Danielle Blythe

    2013-03-01

    Massive stars have a profound influence on their surroundings. However, relatively little is known about their formation. The study of massive star formation is hindered by a lack of observational evidence, primarily due to difficulties observing massive stars at early stages in their development. The Red MSX Source survey (RMS survey) is a valuable tool with which to address these issues. Near-infrared H- and K-band spectra were taken for 247 candidate massive young stellar objects (MYSOs), selected from the RMS survey. 195 (∼80%) of the targets are YSOs, of which 131 are massive YSOs (LBOL>5E3L⊙, M>8 M⊙). This is the largest spectroscopic study of massive YSOs to date. This study covers minimally obscured objects right through to very red, dusty sources. Almost all YSOs show some evidence for emission lines, though there is a wide variety of observed properties, with HI, H2 Fe II, and CO among the most commonly observed lines. Evidence for disks and outflows was frequently seen. Comparisons of Brγ and H2 emission with low mass YSOs suggest that the emission mechanism for these lines is the same for low-, intermediate-, and high-mass YSOs, i.e. high-mass YSOs appear to resemble scaled-up versions of low-mass YSOs. It was found that the YSOs form an evolutionary sequence, based on their spectra, consistent with the existing theoretical models. Type I YSOs have strong H2 emission, no ionized lines, and are redder than the other two subtypes. As such, these are considered to be the youngest sources. The Type III sources are bluest, and therefore considered to be the oldest subtype. They have strong H I lines and fluorescent Fe II 1.6878 μm emission. They may also have weak H2 emission. Type III sources may even be beginning to form a mini-H II region. XSHOOTER data from 10 Herbig Be stars were analysed. The evidence suggests that winds and disks are common among Herbig stars, as they are among their main sequence classical Be star counterparts. Line

  18. Assessment of Interobserver Reliability in Nutrition Studies that Use Direct Observation of School Meals

    PubMed Central

    BAGLIO, MICHELLE L.; BAXTER, SUZANNE DOMEL; GUINN, CAROLINE H.; THOMPSON, WILLIAM O.; SHAFFER, NICOLE M.; FRYE, FRANCESCA H. A.

    2005-01-01

    This article (a) provides a general review of interobserver reliability (IOR) and (b) describes our method for assessing IOR for items and amounts consumed during school meals for a series of studies regarding the accuracy of fourth-grade children's dietary recalls validated with direct observation of school meals. A widely used validation method for dietary assessment is direct observation of meals. Although many studies utilize several people to conduct direct observations, few published studies indicate whether IOR was assessed. Assessment of IOR is necessary to determine that the information collected does not depend on who conducted the observation. Two strengths of our method for assessing IOR are that IOR was assessed regularly throughout the data collection period and that IOR was assessed for foods at the item and amount level instead of at the nutrient level. Adequate agreement among observers is essential to the reasoning behind using observation as a validation tool. Readers are encouraged to question the results of studies that fail to mention and/or to include the results for assessment of IOR when multiple people have conducted observations. PMID:15354155

  19. An accuracy measurement method for star trackers based on direct astronomic observation

    PubMed Central

    Sun, Ting; Xing, Fei; Wang, Xiaochu; You, Zheng; Chu, Daping

    2016-01-01

    Star tracker is one of the most promising optical attitude measurement devices and it is widely used in spacecraft for its high accuracy. However, how to realize and verify such an accuracy remains a crucial but unsolved issue until now. The authenticity of the accuracy measurement method of a star tracker will eventually determine the satellite performance. A new and robust accuracy measurement method for a star tracker based on the direct astronomical observation is proposed here. In comparison with the conventional method with simulated stars, this method utilizes real navigation stars as observation targets which makes the measurement results more authoritative and authentic. Transformations between different coordinate systems are conducted on the account of the precision movements of the Earth, and the error curves of directional vectors are obtained along the three axes. Based on error analysis and accuracy definitions, a three-axis accuracy evaluation criterion has been proposed in this paper, which could determine pointing and rolling accuracy of a star tracker directly. Experimental measurements confirm that this method is effective and convenient to implement. Such a measurement environment is close to the in-orbit conditions and it can satisfy the stringent requirement for high-accuracy star trackers. PMID:26948412

  20. An accuracy measurement method for star trackers based on direct astronomic observation.

    PubMed

    Sun, Ting; Xing, Fei; Wang, Xiaochu; You, Zheng; Chu, Daping

    2016-03-07

    Star tracker is one of the most promising optical attitude measurement devices and it is widely used in spacecraft for its high accuracy. However, how to realize and verify such an accuracy remains a crucial but unsolved issue until now. The authenticity of the accuracy measurement method of a star tracker will eventually determine the satellite performance. A new and robust accuracy measurement method for a star tracker based on the direct astronomical observation is proposed here. In comparison with the conventional method with simulated stars, this method utilizes real navigation stars as observation targets which makes the measurement results more authoritative and authentic. Transformations between different coordinate systems are conducted on the account of the precision movements of the Earth, and the error curves of directional vectors are obtained along the three axes. Based on error analysis and accuracy definitions, a three-axis accuracy evaluation criterion has been proposed in this paper, which could determine pointing and rolling accuracy of a star tracker directly. Experimental measurements confirm that this method is effective and convenient to implement. Such a measurement environment is close to the in-orbit conditions and it can satisfy the stringent requirement for high-accuracy star trackers.

  1. Extending Value of Information Methods to Include the Co-Net Benefits of Earth Observations

    NASA Astrophysics Data System (ADS)

    Macauley, M.

    2015-12-01

    The widening relevance of Earth observations information across the spectrum of natural and environmental resources markedly enhances the value of these observations. An example is observations of forest extent, species composition, health, and change; this information can help in assessing carbon sequestration, biodiversity and habitat, watershed management, fuelwood potential, and other ecosystem services as well as inform the opportunity cost of forest removal for alternative land use such as agriculture, pasture, or development. These "stacked" indicators or co- net benefits add significant value to Earth observations. In part because of reliance on case studies, much previous research about the value of information from Earth observations has assessed individual applications rather than aggregate across applications, thus tending to undervalue the observations. Aggregating across applications is difficult, however, because it requires common units of measurement: controlling for spatial, spectral, and temporal attributes of the observations; and consistent application of value of information techniques. This paper will discuss general principles of co-net benefit aggregation and illustrate its application to attributing value to Earth observations.

  2. Incorporating Animals in Phenological Assessments: USA National Phenology Network Methods to Observe Animal Phenology

    NASA Astrophysics Data System (ADS)

    Miller-Rushing, A. J.; Weltzin, J. F.

    2009-12-01

    Many assessments of phenology, particularly those operating at large scales, focus on the phenology of plants, in part because of the relevance of plants in cycles of leaf greening and browning that are visible from satellite-based remote sensing, and because plants contribute significantly to global and regional biogeochemical cycles. The USA National Phenology Network (USA-NPN), a consortium of individuals, agencies, and organizations, promotes integrated assessments of both plant and animal phenology. The network is currently developing standard methods to add animal phenology to existing assessments of plant phenology. The first phase will of the standard methods will be implemented online in spring 2010. The methods for observing animals will be similar to the standard methods for making on-the-ground observations of plants—observers will be asked to monitor a fixed location regularly throughout the year. During each visit, observers will answer a series of “yes-no” questions that address the phenological state of the species of interest: Is the species present? Is it mating? Is it feeding? And so on. We are currently testing this method in several national parks in the northeastern United States, including Acadia National Park and the Appalachian Trail. By collecting new observations of this sort for a range of animals—amphibians, birds, fish, insects, mammals, and reptiles—we will greatly increase the ability of scientists and natural resource managers to understand how temporal relationships among these species and the plants on which they depend may be changing. To bolster the data available, we are collaborating with existing monitoring programs to develop common monitoring techniques, data sharing technologies, and visualizations. We are also beginning to collect legacy datasets, such as one from North American Bird Phenology Program that includes 90 years of observations of bird migration times from across the continent. We believe that

  3. 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

  4. A conceptual framework for evaluating data suitability for observational studies.

    PubMed

    Shang, Ning; Weng, Chunhua; Hripcsak, George

    2017-09-08

    To contribute a conceptual framework for evaluating data suitability to satisfy the research needs of observational studies. Suitability considerations were derived from a systematic literature review on researchers' common data needs in observational studies and a scoping review on frequent clinical database design considerations, and were harmonized to construct a suitability conceptual framework using a bottom-up approach. The relationships among the suitability categories are explored from the perspective of 4 facets of data: intrinsic, contextual, representational, and accessible. A web-based national survey of domain experts was conducted to validate the framework. Data suitability for observational studies hinges on the following key categories: Explicitness of Policy and Data Governance, Relevance, Availability of Descriptive Metadata and Provenance Documentation, Usability, and Quality. We describe 16 measures and 33 sub-measures. The survey uncovered the relevance of all categories, with a 5-point Likert importance score of 3.9 ± 1.0 for Explicitness of Policy and Data Governance, 4.1 ± 1.0 for Relevance, 3.9 ± 0.9 for Availability of Descriptive Metadata and Provenance Documentation, 4.2 ± 1.0 for Usability, and 4.0 ± 0.9 for Quality. The suitability framework evaluates a clinical data source's fitness for research use. Its construction reflects both researchers' points of view and data custodians' design features. The feedback from domain experts rated Usability, Relevance, and Quality categories as the most important considerations. © The Author 2017. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  5. Globally Gridded Satellite (GridSat) Observations for Climate Studies

    NASA Technical Reports Server (NTRS)

    Knapp, Kenneth R.; Ansari, Steve; Bain, Caroline L.; Bourassa, Mark A.; Dickinson, Michael J.; Funk, Chris; Helms, Chip N.; Hennon, Christopher C.; Holmes, Christopher D.; Huffman, George J.; hide

    2012-01-01

    Geostationary satellites have provided routine, high temporal resolution Earth observations since the 1970s. Despite the long period of record, use of these data in climate studies has been limited for numerous reasons, among them: there is no central archive of geostationary data for all international satellites, full temporal and spatial resolution data are voluminous, and diverse calibration and navigation formats encumber the uniform processing needed for multi-satellite climate studies. The International Satellite Cloud Climatology Project set the stage for overcoming these issues by archiving a subset of the full resolution geostationary data at approx.10 km resolution at 3 hourly intervals since 1983. Recent efforts at NOAA s National Climatic Data Center to provide convenient access to these data include remapping the data to a standard map projection, recalibrating the data to optimize temporal homogeneity, extending the record of observations back to 1980, and reformatting the data for broad public distribution. The Gridded Satellite (GridSat) dataset includes observations from the visible, infrared window, and infrared water vapor channels. Data are stored in the netCDF format using standards that permit a wide variety of tools and libraries to quickly and easily process the data. A novel data layering approach, together with appropriate satellite and file metadata, allows users to access GridSat data at varying levels of complexity based on their needs. The result is a climate data record already in use by the meteorological community. Examples include reanalysis of tropical cyclones, studies of global precipitation, and detection and tracking of the intertropical convergence zone.

  6. Palliative care team visits. Qualitative study through participant observation.

    PubMed

    Alfaya Góngora, Maria Del Mar; Bueno Pernias, Maria José; Hueso Montoro, César; Guardia Mancilla, Plácido; Montoya Juárez, Rafael; García Caro, Maria Paz

    2016-03-30

    To describe the clinical encounters that occur when a palliative care team provides patient care and the features that influence these encounters and indicate whether they are favorable or unfavorable depending on the expectations and feelings of the various participants. A qualitative case study conducted via participant observation. A total of 12 observations of the meetings of palliative care teams with patients and families in different settings (home, hospital and consultation room) were performed. The visits were follow-up or first visits, either scheduled or on demand. Content analysis of the observation was performed. The analysis showed the normal follow-up activity of the palliative care unit that was focused on controlling symptoms, sharing information and providing advice on therapeutic regimens and care. The environment appeared to condition the patients' expressions and the type of patient relationship. Favorable clinical encounter conditions included kindness and gratitude. Unfavorable conditions were deterioration caused by approaching death, unrealistic family objectives and limited resources. Home visits from basic palliative care teams play an important role in patient and family well-being. The visits seem to focus on controlling symptoms and are conditioned by available resources.

  7. A Statistical Study of Interplanetary Type II Bursts: STEREO Observations

    NASA Astrophysics Data System (ADS)

    Krupar, V.; Eastwood, J. P.; Magdalenic, J.; Gopalswamy, N.; Kruparova, O.; Szabo, A.

    2017-12-01

    Coronal mass ejections (CMEs) are the primary cause of the most severe and disruptive space weather events such as solar energetic particle (SEP) events and geomagnetic storms at Earth. Interplanetary type II bursts are generated via the plasma emission mechanism by energetic electrons accelerated at CME-driven shock waves and hence identify CMEs that potentially cause space weather impact. As CMEs propagate outward from the Sun, radio emissions are generated at progressively at lower frequencies corresponding to a decreasing ambient solar wind plasma density. We have performed a statistical study of 153 interplanetary type II bursts observed by the two STEREO spacecraft between March 2008 and August 2014. These events have been correlated with manually-identified CMEs contained in the Heliospheric Cataloguing, Analysis and Techniques Service (HELCATS) catalogue. Our results confirm that faster CMEs are more likely to produce interplanetary type II radio bursts. We have compared observed frequency drifts with white-light observations to estimate angular deviations of type II burst propagation directions from radial. We have found that interplanetary type II bursts preferably arise from CME flanks. Finally, we discuss a visibility of radio emissions in relation to the CME propagation direction.

  8. A 3D tomographic reconstruction method to analyze Jupiter's electron-belt emission observations

    NASA Astrophysics Data System (ADS)

    Santos-Costa, Daniel; Girard, Julien; Tasse, Cyril; Zarka, Philippe; Kita, Hajime; Tsuchiya, Fuminori; Misawa, Hiroaki; Clark, George; Bagenal, Fran; Imai, Masafumi; Becker, Heidi N.; Janssen, Michael A.; Bolton, Scott J.; Levin, Steve M.; Connerney, John E. P.

    2017-04-01

    Multi-dimensional reconstruction techniques of Jupiter's synchrotron radiation from radio-interferometric observations were first developed by Sault et al. [Astron. Astrophys., 324, 1190-1196, 1997]. The tomographic-like technique introduced 20 years ago had permitted the first 3-dimensional mapping of the brightness distribution around the planet. This technique has demonstrated the advantage to be weakly dependent on planetary field models. It also does not require any knowledge on the energy and spatial distributions of the radiating electrons. On the downside, it is assumed that the volume emissivity of any punctual point source around the planet is isotropic. This assumption becomes incorrect when mapping the brightness distribution for non-equatorial point sources or any point sources from Juno's perspective. In this paper, we present our modeling effort to bypass the isotropy issue. Our approach is to use radio-interferometric observations and determine the 3-D brightness distribution in a cylindrical coordinate system. For each set (z, r), we constrain the longitudinal distribution with a Fourier series and the anisotropy is addressed with a simple periodic function when possible. We develop this new method over a wide range of frequencies using past VLA and LOFAR observations of Jupiter. We plan to test this reconstruction method with observations of Jupiter that are currently being carried out with LOFAR and GMRT in support to the Juno mission. We describe how this new 3D tomographic reconstruction method provides new model constraints on the energy and spatial distributions of Jupiter's ultra-relativistic electrons close to the planet and be used to interpret Juno MWR observations of Jupiter's electron-belt emission and assist in evaluating the background noise from the radiation environment in the atmospheric measurements.

  9. A Method to Retrieve Rainfall Rate Over Land from TRMM Microwave Imager Observations

    NASA Technical Reports Server (NTRS)

    Prabhakara, C.; Iacovazzi, R., Jr.; Yoo, J.-M.; Lau, William K. M. (Technical Monitor)

    2002-01-01

    Over tropical land regions, rain rate maxima in mesoscale convective systems revealed by the Precipitation Radar (PR) flown on the Tropical Rainfall Measuring Mission (TRMM) satellite are found to correspond to thunderstorms, i.e., Cbs. These Cbs are reflected as minima in the 85 GHz brightness temperature, T85, observed by the TRMM Microwave Imager (TMI) radiometer. Because the magnitude of TMI observations do not discriminate satisfactorily convective and stratiform rain, we developed here a different TMI discrimination method. In this method, two types of Cbs, strong and weak, are inferred from the Laplacian of T85 at minima. Then, to retrieve rain rate, where T85 is less than 270 K, a weak (background) rain rate is deduced using T85 observations. Furthermore, over a circular area of 10 km radius centered at the location of each T85 minimum, an additional Cb component of rain rate is added to the background rain rate. This Cb component of rain rate is estimated with the help of (T19-T37) and T85 observations. Initially, our algorithm is calibrated with the PR rain rate measurements from 20 MCS rain events. After calibration, this method is applied to TMI data taken from several tropical land regions. With the help of the PR observations, we show that the spatial distribution and intensity of rain rate over land estimated from our algorithm are better than those given by the current TMI-Version-5 Algorithm. For this reason, our algorithm may be used to improve the current state of rain retrievals on land.

  10. A statistical study of merging galaxies: Theory and observations

    NASA Technical Reports Server (NTRS)

    Chatterjee, Tapan K.

    1990-01-01

    A study of the expected frequency of merging galaxies is conducted, using the impulsive approximation. Results indicate that if we consider mergers involving galaxy pairs without halos in a single crossing time or orbital period, the expected frequency of mergers is two orders of magnitude below the observed value for the present epoch. If we consider mergers involving several orbital periods or crossing times, the expected frequency goes up by an order of magnitude. Preliminary calculation indicate that if we consider galaxy mergers between pairs with massive halos, the merger is very much hastened.

  11. An observational study of emergency department intern activities.

    PubMed

    Zhu, Jia Ni; Weiland, Tracey J; Taylor, David M; Dent, Andrew W

    2008-05-05

    To describe how intern time is spent, and the frequency of activities performed by interns during emergency department (ED) rotations. Prospective observational study of 42 ED interns from three Melbourne city teaching hospitals during 5 months in 2006. Direct observations were made by a single researcher for 390.8 hours, sampling all days of the week and all hours of the day. Proportion of time spent on tasks and number of procedures performed or observed by interns. Direct patient-related tasks accounted for 86.6% of total intern time, including 43.9% spent on liaising and documentation, 17.5% obtaining patient histories, 9.3% on physical examinations, 5.6% on procedures, 4.8% ordering or interpreting investigations, 3.0% on handover and 4.9% on other clinical activities. Intern time spent on non-clinical activities included 4.2% on breaks, 3.7% on downtime, 1.7% on education, and 1.3% on teaching others. Adjusted for an 8-week term, the ED intern would take 253 patient histories, consult more senior ED staff on 683 occasions, perform 237 intravenous cannulations/phlebotomies, 39 arterial punctures, 12 wound repairs and apply 16 plasters. They would perform chest compressions under supervision on seven occasions, observe defibrillation twice and intubation once, but may not see a thoracostomy. The ED exposes interns to a broad range of activities. With the anticipated increase in intern numbers, dilution of the emergency medicine experience may occur, and requirements for supervision may increase. Substitution of ED rotations may deprive interns of a valuable learning experience.

  12. Nursing praxis, compassionate caring and interpersonal relations: an observational study.

    PubMed

    Fry, Margaret; MacGregor, Casimir; Ruperto, Kate; Jarrett, Kate; Wheeler, Janet; Fong, Jacqueline; Fetchet, Wendy

    2013-05-01

    The Clinical Initiative Nurse (CIN) is a role that requires experienced emergency nurses to assess, initiate diagnostic tests, treat and manage a range of patient conditions. The CIN role is focused on the waiting room and to 'communicate the wait', initiate diagnostics or treatment and follow-up for waiting room patients. We aim to explore what emergency nurses' do in their extended practice role in observable everyday life in the emergency department (ED). The paper argues that compassionate caring is a core nursing skill that supports CIN interpersonal relations, despite the role's highly clinical nature. Sixteen non-participant observations were undertaken in three EDs in New South Wales, Australia. Nurses were eligible for inclusion if they had two years of emergency experience and had worked in the CIN role for more than one year. All CIN's that were observed were highly experienced with a minimum three year ED experience. The CIN observations revealed how compassionate caring was utilised by CIN's to quickly build a therapeutic relationship with patients and colleagues, and helped to facilitate core communication and interpersonal skills. While the CIN role was viewed as extended practice, the role relied heavily on compassionate care to support interpersonal relationships and to actualise extended practice care. The study supports the contribution made by emergency nurses and demonstrates how compassionate caring is central to nursing praxis. This paper also demonstrates that the CIN role utilises a complex mix between advanced clinical skills and compassion that supports interpersonal and therapeutic relationships. Further research is needed to understand how compassionate care can be optimised within nursing praxis and the duty of care between nurses and patients, nurses and other health care professionals so that future healthcare goals can be realised. Copyright © 2013 College of Emergency Nursing Australasia Ltd. All rights reserved.

  13. Interpolation of Superconducting Gravity Observations Using Least-Squares Collocation Method

    NASA Astrophysics Data System (ADS)

    Habel, Branislav; Janak, Juraj

    2014-05-01

    A pre-processing of the gravity data measured by superconducting gravimeter involves removing of spikes, offsets and gaps. Their presence in observations can limit the data analysis and degrades the quality of obtained results. Short data gaps are filling by theoretical signal in order to get continuous records of gravity. It requires the accurate tidal model and eventually atmospheric pressure at the observed site. The poster presents a design of algorithm for interpolation of gravity observations with a sampling rate of 1 min. Novel approach is based on least-squares collocation which combines adjustment of trend parameters, filtering of noise and prediction. It allows the interpolation of missing data up to a few hours without necessity of any other information. Appropriate parameters for covariance function are found using a Bayes' theorem by modified optimization process. Accuracy of method is improved by the rejection of outliers before interpolation. For filling of longer gaps the collocation model is combined with theoretical tidal signal for the rigid Earth. Finally, the proposed method was tested on the superconducting gravity observations at several selected stations of Global Geodynamics Project. Testing demonstrates its reliability and offers results comparable with the standard approach implemented in ETERNA software package without necessity of an accurate tidal model.

  14. Model Uncertainty Quantification Methods For Data Assimilation In Partially Observed Multi-Scale Systems

    NASA Astrophysics Data System (ADS)

    Pathiraja, S. D.; van Leeuwen, P. J.

    2017-12-01

    Model Uncertainty Quantification remains one of the central challenges of effective Data Assimilation (DA) in complex partially observed non-linear systems. Stochastic parameterization methods have been proposed in recent years as a means of capturing the uncertainty associated with unresolved sub-grid scale processes. Such approaches generally require some knowledge of the true sub-grid scale process or rely on full observations of the larger scale resolved process. We present a methodology for estimating the statistics of sub-grid scale processes using only partial observations of the resolved process. It finds model error realisations over a training period by minimizing their conditional variance, constrained by available observations. Special is that these realisations are binned conditioned on the previous model state during the minimization process, allowing for the recovery of complex error structures. The efficacy of the approach is demonstrated through numerical experiments on the multi-scale Lorenz 96' model. We consider different parameterizations of the model with both small and large time scale separations between slow and fast variables. Results are compared to two existing methods for accounting for model uncertainty in DA and shown to provide improved analyses and forecasts.

  15. Critical Analysis of Different Methods to Retrieve Atmosphere Humidity Profiles from GNSS Radio Occultation Observations

    NASA Astrophysics Data System (ADS)

    Vespe, Francesco; Benedetto, Catia

    2013-04-01

    The huge amount of GPS Radio Occultation (RO) observations currently available thanks to space mission like COSMIC, CHAMP, GRACE, TERRASAR-X etc., have greatly encouraged the research of new algorithms suitable to extract humidity, temperature and pressure profiles of the atmosphere in a more and more precise way. For what concern the humidity profiles in these last years two different approaches have been widely proved and applied: the "Simple" and the 1DVAR methods. The Simple methods essentially determine dry refractivity profiles from temperature analysis profiles and hydrostatic equation. Then the dry refractivity is subtracted from RO refractivity to achieve the wet component. Finally from the wet refractivity is achieved humidity. The 1DVAR approach combines RO observations with profiles given by the background models with both the terms weighted with the inverse of covariance matrix. The advantage of "Simple" methods is that they are not affected by bias due to the background models. We have proposed in the past the BPV approach to retrieve humidity. Our approach can be classified among the "Simple" methods. The BPV approach works with dry atmospheric CIRA-Q models which depend on latitude, DoY and height. The dry CIRA-Q refractivity profile is selected estimating the involved parameters in a non linear least square fashion achieved by fitting RO observed bending angles through the stratosphere. The BPV as well as all the other "Simple" methods, has as drawback the unphysical occurrence of negative "humidity". Thus we propose to apply a modulated weighting of the fit residuals just to minimize the effects of this inconvenient. After a proper tuning of the approach, we plan to present the results of the validation.

  16. Observation method to predict meander migration and vertical degradation of rivers.

    DOT National Transportation Integrated Search

    2014-05-01

    Meander migration and vertical degradation of river bed are processes that have been studied for years. : Different methods have been proposed to make predictions of the behavior of rivers with respect to these : processes. These two erosion controll...

  17. Change Semantic Constrained Online Data Cleaning Method for Real-Time Observational Data Stream

    NASA Astrophysics Data System (ADS)

    Ding, Yulin; Lin, Hui; Li, Rongrong

    2016-06-01

    to large estimation error. In order to achieve the best generalization error, it is an important challenge for the data cleaning methodology to be able to characterize the behavior of data stream distributions and adaptively update a model to include new information and remove old information. However, the complicated data changing property invalidates traditional data cleaning methods, which rely on the assumption of a stationary data distribution, and drives the need for more dynamic and adaptive online data cleaning methods. To overcome these shortcomings, this paper presents a change semantics constrained online filtering method for real-time observational data. Based on the principle that the filter parameter should vary in accordance to the data change patterns, this paper embeds semantic description, which quantitatively depicts the change patterns in the data distribution to self-adapt the filter parameter automatically. Real-time observational water level data streams of different precipitation scenarios are selected for testing. Experimental results prove that by means of this method, more accurate and reliable water level information can be available, which is prior to scientific and prompt flood assessment and decision-making.

  18. Cellular transplants in amyotrophic lateral sclerosis patients: an observational study.

    PubMed

    Gamez, Josep; Carmona, Francesc; Raguer, Nuria; Ferrer-Sancho, Jaume; Martín-Henao, Gregorio A; Martí-Beltrán, Sergi; Badia, Merce; Gratacós, Margarita; Rodriguez-Gónzalez, Esther; Seoane, Jose Luis; Pallero-Castillo, Mercedes; Burgos, Rosa; Puiggros, Carolina; Pasarin, Alejandro; Bori-Fortuny, Inmaculada

    2010-09-01

    Cytotherapy is a promising option for neurodegenerative disease treatment. Because of the fatal prognosis and imperative need for effective treatment, amyotrophic lateral sclerosis (ALS) patients request this therapy before its effectiveness has been verified. The increase in clinics offering cytotherapies but providing little scientific information has prompted considerable medical tourism. We present an observational study of Spanish ALS patients receiving cytotherapy, analyzing the experiences arising from the treatment (TX) and considering two progression markers, FVC and ALSFRS-R. Twelve ALS patients with a mean age of 48.6 years (SD 12.8) received cytotherapy 26.9 months (SD 15.8) after clinical onset. ALSFRS-R and FVC at TX were 32.3 (SD 6.8) and 63.4% (SD 15.3), respectively. TX involved transplants of olfactory ensheathing cells in three patients, and autologous mesenchymal stromal cells in the remainder. One patient died 33 months post-TX after surviving for 49 months. Five required mechanical non-invasive home ventilation 7.4 months post-TX. Two required invasive ventilation 13 months post-TX. Five patients needed gastrostomy feeding 23.3 months post-TX. Survival between clinical onset and the study end date was 50 months (SD 17.2). No significant adverse events or changes in the decline of FVC and ALSFRS-R compared with the disease's natural history were observed. Our observations suggest that these therapies do not halt the course of the disease. Cytotherapy cannot yet be considered a curative treatment for ALS.

  19. Guideline adaptation and implementation planning: a prospective observational study

    PubMed Central

    2013-01-01

    Background Adaptation of high-quality practice guidelines for local use has been advanced as an efficient means to improve acceptability and applicability of evidence-informed care. In a pan-Canadian study, we examined how cancer care groups adapted pre-existing guidelines to their unique context and began implementation planning. Methods Using a mixed-methods, case-study design, five cases were purposefully sampled from self-identified groups and followed as they used a structured method and resources for guideline adaptation. Cases received the ADAPTE Collaboration toolkit, facilitation, methodological and logistical support, resources and assistance as required. Documentary and primary data collection methods captured individual case experience, including monthly summaries of meeting and field notes, email/telephone correspondence, and project records. Site visits, process audits, interviews, and a final evaluation forum with all cases contributed to a comprehensive account of participant experience. Results Study cases took 12 to >24 months to complete guideline adaptation. Although participants appreciated the structure, most found the ADAPTE method complex and lacking practical aspects. They needed assistance establishing individual guideline mandate and infrastructure, articulating health questions, executing search strategies, appraising evidence, and achieving consensus. Facilitation was described as a multi-faceted process, a team effort, and an essential ingredient for guideline adaptation. While front-line care providers implicitly identified implementation issues during adaptation, they identified a need to add an explicit implementation planning component. Conclusions Guideline adaptation is a positive initial step toward evidence-informed care, but adaptation (vs. ‘de novo’ development) did not meet expectations for reducing time or resource commitments. Undertaking adaptation is as much about the process (engagement and capacity building) as it

  20. Hypomagnesemia associated with hypocalcemia after total thyroidectomy: an observational study.

    PubMed

    Mahmoud, Renata Regina da Graça Lorencetti; Neto, Vergilius José Furtado de Araujo; Alves, Wellington; Lin, Chin Shien; Leite, Ana Kober Nogueira; Matos, Leandro Luongo; Filho, Vergilius José Furtado de Araujo; Cernea, Claudio Roberto

    2016-06-01

    Serum magnesium is frequently low in patients with hypocalcemia after total thyroidectomy. The aim of the present study was to analyze the variations in serum magnesium and calcium concentrations after total thyroidectomy, and the relationship between both ions. We conducted an observational study of 142 patients who had undergone total thyroidectomy, measuring serum calcium and magnesium levels preoperatively and on the day following surgery. The incidence of postoperative hypocalcemia was compared with that of postoperative hypomagnesemia. A total of 142, total thyroidectomies were performed: 54 patients (38%) presented with hypocalcemia on the first postoperative day. A marked decrease in blood magnesium in the group of patients with hypocalcemia was observed when compared to those with normal calcemia on the first postoperative day (mean variation respectively, 0.125 ± 0.065 mmol/L versus 0.035 ± 0.020 mmol/L; P = 0.0002). Hypomagnesemia is significantly associated with early hypocalcemia following thyroidectomy.

  1. Safety Hazards During Intrahospital Transport: A Prospective Observational Study.

    PubMed

    Bergman, Lina M; Pettersson, Monica E; Chaboyer, Wendy P; Carlström, Eric D; Ringdal, Mona L

    2017-10-01

    To identify, classify, and describe safety hazards during the process of intrahospital transport of critically ill patients. A prospective observational study. Data from participant observations of the intrahospital transport process were collected over a period of 3 months. The study was undertaken at two ICUs in one university hospital. Critically ill patients transported within the hospital by critical care nurses, unlicensed nurses, and physicians. None. Content analysis was performed using deductive and inductive approaches. We detected a total of 365 safety hazards (median, 7; interquartile range, 4-10) during 51 intrahospital transports of critically ill patients, 80% of whom were mechanically ventilated. The majority of detected safety hazards were assessed as increasing the risk of harm, compromising patient safety (n = 204). Using the System Engineering Initiative for Patient Safety, we identified safety hazards related to the work system, as follows: team (n = 61), tasks (n = 83), tools and technologies (n = 124), environment (n = 48), and organization (n = 49). Inductive analysis provided an in-depth description of those safety hazards, contributing factors, and process-related outcomes. Findings suggest that intrahospital transport is a hazardous process for critically ill patients. We have identified several factors that may contribute to transport-related adverse events, which will provide the opportunity for the redesign of systems to enhance patient safety.

  2. An observational study of entrainment rate in deep convection

    DOE PAGES

    Guo, Xiaohao; Lu, Chunsong; Zhao, Tianliang; ...

    2015-09-22

    This study estimates entrainment rate and investigates its relationships with cloud properties in 156 deep convective clouds based on in-situ aircraft observations during the TOGA-COARE (Tropical Ocean Global Atmosphere Coupled Ocean Atmosphere Response Experiment) field campaign over the western Pacific. To the authors’ knowledge, this is the first study on the probability density function of entrainment rate, the relationships between entrainment rate and cloud microphysics, and the effects of dry air sources on the calculated entrainment rate in deep convection from an observational perspective. Results show that the probability density function of entrainment rate can be well fitted by lognormal,more » gamma or Weibull distribution, with coefficients of determination being 0.82, 0.85 and 0.80, respectively. Entrainment tends to reduce temperature, water vapor content and moist static energy in cloud due to evaporative cooling and dilution. Inspection of the relationships between entrainment rate and microphysical properties reveals a negative correlation between volume-mean radius and entrainment rate, suggesting the potential dominance of homogeneous mechanism in the clouds examined. The entrainment rate and environmental water vapor content show similar tendencies of variation with the distance of the assumed environmental air to the cloud edges. Their variation tendencies are non-monotonic due to the relatively short distance between adjacent clouds.« less

  3. An observational study of entrainment rate in deep convection

    SciTech Connect

    Guo, Xiaohao; Lu, Chunsong; Zhao, Tianliang

    This study estimates entrainment rate and investigates its relationships with cloud properties in 156 deep convective clouds based on in-situ aircraft observations during the TOGA-COARE (Tropical Ocean Global Atmosphere Coupled Ocean Atmosphere Response Experiment) field campaign over the western Pacific. To the authors’ knowledge, this is the first study on the probability density function of entrainment rate, the relationships between entrainment rate and cloud microphysics, and the effects of dry air sources on the calculated entrainment rate in deep convection from an observational perspective. Results show that the probability density function of entrainment rate can be well fitted by lognormal,more » gamma or Weibull distribution, with coefficients of determination being 0.82, 0.85 and 0.80, respectively. Entrainment tends to reduce temperature, water vapor content and moist static energy in cloud due to evaporative cooling and dilution. Inspection of the relationships between entrainment rate and microphysical properties reveals a negative correlation between volume-mean radius and entrainment rate, suggesting the potential dominance of homogeneous mechanism in the clouds examined. The entrainment rate and environmental water vapor content show similar tendencies of variation with the distance of the assumed environmental air to the cloud edges. Their variation tendencies are non-monotonic due to the relatively short distance between adjacent clouds.« less

  4. Technological aspects of hospital communication challenges: an observational study.

    PubMed

    Popovici, Ilinca; Morita, Plinio P; Doran, Diane; Lapinsky, Stephen; Morra, Dante; Shier, Ashleigh; Wu, Robert; Cafazzo, Joseph A

    2015-06-01

    To gain insights into how technological communication tools impact effective communication among clinicians, which is critical for patient safety. This multi-site observational study analyzes inter-clinician communication and interaction with information technology, with a focus on the critical process of patient transfer from the Emergency Department to General Internal Medicine. Mount Sinai Hospital, Sunnybrook Health Sciences Centre and Toronto General Hospital. At least five ED and general internal medicine nurses and physicians directly involved in patient transfers were observed on separate occasions at each institution. N/A. N/A. The study provides insight into clinician workflow, evaluates current hospital communication systems and identifies key issues affecting communication: interruptions, issues with numeric pagers, lack of integrated communication tools, lack of awareness of consultation status, inefficiencies related to the paper chart, unintuitive user interfaces, mixed use of electronic and paper systems and lack of up-to-date contact information. It also identifies design trade-offs to be negotiated: synchronous communication vs. reducing interruptions, notification of patient status vs. reducing interruptions and speed vs. quality of handovers. The issues listed should be considered in the design of new technology for hospital communications. © The Author 2015. Published by Oxford University Press in association with the International Society for Quality in Health Care; all rights reserved.

  5. Development of a Method to Observe Preschoolers' Packed Lunches in Early Care and Education Centers.

    PubMed

    Sweitzer, Sara J; Byrd-Williams, Courtney E; Ranjit, Nalini; Romo-Palafox, Maria Jose; Briley, Margaret E; Roberts-Gray, Cynthia R; Hoelscher, Deanna M

    2015-08-01

    As early childhood education (ECE) centers become a more common setting for nutrition interventions, a variety of data collection methods are required, based on the center foodservice. ECE centers that require parents to send in meals and/or snacks from home present a unique challenge for accurate nutrition estimation and data collection. We present an observational methodology for recording the contents and temperature of preschool-aged children's lunchboxes and data to support a 2-day vs a 3-day collection period. Lunchbox observers were trained in visual estimation of foods based on Child and Adult Care Food Program and MyPlate servings and household recommended measures. Trainees weighed and measured foods commonly found in preschool-aged children's lunchboxes and practiced recording accurate descriptions and food temperatures. Training included test assessments of whole-grain bread products, mixed dishes such as macaroni and cheese, and a variety of sandwich preparations. Validity of the estimation method was tested by comparing estimated to actual amounts for several distinct food types. Reliability was assessed by computing the intraclass correlation coefficient for each observer as well as an interrater reliability coefficient across observers. To compare 2- and 3-day observations, 2 of the 3 days of observations were randomly selected for each child and analyzed as a separate dataset. Linear model estimated mean and standard error of whole grains, fruits and vegetables, and amounts of energy, carbohydrates, protein, total fat, saturated fat, dietary fiber, thiamin, riboflavin, niacin, vitamins A and C, calcium, iron, sodium, and dietary fiber per lunch were compared across the 2- and 3-day observation datasets. The mean estimated amounts across 11 observers were statistically indistinguishable from the measured portion size for each of the 41 test foods, implying that the visual estimation measurement method was valid: intraobserver intraclass correlation

  6. Inverse Abbe-method for observing small refractive index changes in liquids.

    PubMed

    Räty, Jukka; Peiponen, Kai-Erik

    2015-05-01

    This study concerns an optical method for the detection of minuscule refractive index changes in the liquid phase. The proposed method reverses the operation of the traditional Abbe refractometer and thus utilizes the light dispersion properties of materials, i.e. it involves the dependence of the refractive index on light wavelength. In practice, the method includes the detection of light reflection spectra in the visible spectral range. This inverse Abbe method is suitable for liquid quality studies e.g. for monitoring water purity. Tests have shown that the method reveals less than per mil NaCl or ethanol concentrations in water. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Spacelab Science Results Study. Volume 1; External Observations

    NASA Technical Reports Server (NTRS)

    Naumann, Robert J. (Compiler)

    1999-01-01

    Some of the 36 Spacelab missions were more or less dedicated to specific scientific disciplines, while other carried a eclectic mixture of experiments ranging from astrophysics to life sciences. However, the experiments can be logically classified into two general categories; those that make use of the Shuttle as an observing platform for external phenomena (including those which use the Shuttle in an interactive mode) and those which use the Shuttle as a microgravity laboratory. This first volume of this Spacelab Science Results study will be devoted to experiments of the first category. The disciplines included are Astrophysics, Solar Physics, Space Plasma Physics, Atmospheric Sciences, and Earth Sciences. Because of the large number of microgravity investigations, Volume 2 will be devoted to Microgravity Sciences, which includes Fluid Physics, Combustion Science, Materials Science, and Biotechnology, and Volume 3 will be devoted to Space Life Sciences, which studies the response and adaptability of living organisms to the microgravity environment.

  8. Prospective Observational Study on acute Appendicitis Worldwide (POSAW).

    PubMed

    Sartelli, Massimo; Baiocchi, Gian L; Di Saverio, Salomone; Ferrara, Francesco; Labricciosa, Francesco M; Ansaloni, Luca; Coccolini, Federico; Vijayan, Deepak; Abbas, Ashraf; Abongwa, Hariscine K; Agboola, John; Ahmed, Adamu; Akhmeteli, Lali; Akkapulu, Nezih; Akkucuk, Seckin; Altintoprak, Fatih; Andreiev, Aurelia L; Anyfantakis, Dimitrios; Atanasov, Boiko; Bala, Miklosh; Balalis, Dimitrios; Baraket, Oussama; Bellanova, Giovanni; Beltran, Marcelo; Melo, Renato Bessa; Bini, Roberto; Bouliaris, Konstantinos; Brunelli, Daniele; Castillo, Adrian; Catani, Marco; Che Jusoh, Asri; Chichom-Mefire, Alain; Cocorullo, Gianfranco; Coimbra, Raul; Colak, Elif; Costa, Silvia; Das, Koray; Delibegovic, Samir; Demetrashvili, Zaza; Di Carlo, Isidoro; Kiseleva, Nadezda; El Zalabany, Tamer; Faro, Mario; Ferreira, Margarida; Fraga, Gustavo P; Gachabayov, Mahir; Ghnnam, Wagih M; Giménez Maurel, Teresa; Gkiokas, Georgios; Gomes, Carlos A; Griffiths, Ewen; Guner, Ali; Gupta, Sanjay; Hecker, Andreas; Hirano, Elcio S; Hodonou, Adrien; Hutan, Martin; Ioannidis, Orestis; Isik, Arda; Ivakhov, Georgy; Jain, Sumita; Jokubauskas, Mantas; Karamarkovic, Aleksandar; Kauhanen, Saila; Kaushik, Robin; Kavalakat, Alfie; Kenig, Jakub; Khokha, Vladimir; Khor, Desmond; Kim, Dennis; Kim, Jae I; Kong, Victor; Lasithiotakis, Konstantinos; Leão, Pedro; Leon, Miguel; Litvin, Andrey; Lohsiriwat, Varut; López-Tomassetti Fernandez, Eudaldo; Lostoridis, Eftychios; Maciel, James; Major, Piotr; Dimova, Ana; Manatakis, Dimitrios; Marinis, Athanasio; Martinez-Perez, Aleix; Marwah, Sanjay; McFarlane, Michael; Mesina, Cristian; Pędziwiatr, Michał; Michalopoulos, Nickos; Misiakos, Evangelos; Mohamedahmed, Ali; Moldovanu, Radu; Montori, Giulia; Mysore Narayana, Raghuveer; Negoi, Ionut; Nikolopoulos, Ioannis; Novelli, Giuseppe; Novikovs, Viktors; Olaoye, Iyiade; Omari, Abdelkarim; Ordoñez, Carlos A; Ouadii, Mouaqit; Ozkan, Zeynep; Pal, Ajay; Palini, Gian M; Partecke, Lars I; Pata, Francesco; Pędziwiatr, Michał; Pereira Júnior, Gerson A; Pintar, Tadeja; Pisarska, Magdalena; Ploneda-Valencia, Cesar F; Pouggouras, Konstantinos; Prabhu, Vinod; Ramakrishnapillai, Padmakumar; Regimbeau, Jean-Marc; Reitz, Marianne; Rios-Cruz, Daniel; Saar, Sten; Sakakushev, Boris; Seretis, Charalampos; Sazhin, Alexander; Shelat, Vishal; Skrovina, Matej; Smirnov, Dmitry; Spyropoulos, Charalampos; Strzałka, Marcin; Talving, Peep; Teixeira Gonsaga, Ricardo A; Theobald, George; Tomadze, Gia; Torba, Myftar; Tranà, Cristian; Ulrych, Jan; Uzunoğlu, Mustafa Y; Vasilescu, Alin; Occhionorelli, Savino; Venara, Aurélien; Vereczkei, Andras; Vettoretto, Nereo; Vlad, Nutu; Walędziak, Maciej; Yilmaz, Tonguç U; Yuan, Kuo-Ching; Yunfeng, Cui; Zilinskas, Justas; Grelpois, Gérard; Catena, Fausto

    2018-01-01

    Acute appendicitis (AA) is the most common surgical disease, and appendectomy is the treatment of choice in the majority of cases. A correct diagnosis is key for decreasing the negative appendectomy rate. The management can become difficult in case of complicated appendicitis. The aim of this study is to describe the worldwide clinical and diagnostic work-up and management of AA in surgical departments. This prospective multicenter observational study was performed in 116 worldwide surgical departments from 44 countries over a 6-month period (April 1, 2016-September 30, 2016). All consecutive patients admitted to surgical departments with a clinical diagnosis of AA were included in the study. A total of 4282 patients were enrolled in the POSAW study, 1928 (45%) women and 2354 (55%) men, with a median age of 29 years. Nine hundred and seven (21.2%) patients underwent an abdominal CT scan, 1856 (43.3%) patients an US, and 285 (6.7%) patients both CT scan and US. A total of 4097 (95.7%) patients underwent surgery; 1809 (42.2%) underwent open appendectomy and 2215 (51.7%) had laparoscopic appendectomy. One hundred eighty-five (4.3%) patients were managed conservatively. Major complications occurred in 199 patients (4.6%). The overall mortality rate was 0.28%. The results of the present study confirm the clinical value of imaging techniques and prognostic scores. Appendectomy remains the most effective treatment of acute appendicitis. Mortality rate is low.

  9. A Method to Retrieve Rainfall Rate over Land from TRMM Observations

    NASA Technical Reports Server (NTRS)

    Prabhakara, C.; Iacovazzi, R., Jr.; Yoo, J.-M.

    2002-01-01

    Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR) observations over mesoscale convective systems (MCSs) reveal that there are localized maxima in the rain rate with a scale of about 10 to 20 km that represent thunderstorms (Cbs). Some of these Cbs are developing or intense, while others are decaying or weak. These Cbs constitute only about 20 % of the rain area of a given MCS. Outside of Cbs, the average rain rate is much weaker than that within Cbs. From an analysis of the PR data, we find that the spatial distribution of rain and its character, convective or stratiform, is highly inhomogeneous. This complex nature of rain exists on a scale comparable to that of a Cb. The 85 GHz brightness temperature, T85, observations of the TRMM Microwave Imager (TMI) radiometer taken over an MCS reflect closely the PR rain rate pattern over land. Local maxima in rain rate shown by PR are observed as local minima in T85. Where there are no minima in T85, PR observations indicate there is light rain. However, the TMI brightness temperature measurements (Tbs) have poor ability to discriminate convective rain from stratiform rain. For this reason, a TMI rain retrieval procedure that depends primarily on the magnitude of Tbs performs poorly. In order to retrieve rain rate from TMI data on land one has to include the spatial distribution information deduced from the T85 data in the retrieval method. Then, quantitative estimation of rain rate can be accomplished. A TMI rain retrieval method developed along these lines can yield estimates of rain rate and its frequency distribution which agree closely with that given by PR. We find the current TRMM project TMI (Version 5) rain retrieval algorithm on land could be improved with the retrieval scheme developed here. To support the conceptual frame work of the rain retrieval method developed here, a theoretical analysis of the TMI brightness temperatures in convective and stratiform regions is presented.

  10. Mathematical methods of studying physical phenomena

    NASA Astrophysics Data System (ADS)

    Man'ko, Margarita A.

    2013-03-01

    In recent decades, substantial theoretical and experimental progress was achieved in understanding the quantum nature of physical phenomena that serves as the foundation of present and future quantum technologies. Quantum correlations like the entanglement of the states of composite systems, the phenomenon of quantum discord, which captures other aspects of quantum correlations, quantum contextuality and, connected with these phenomena, uncertainty relations for conjugate variables and entropies, like Shannon and Rényi entropies, and the inequalities for spin states, like Bell inequalities, reflect the recently understood quantum properties of micro and macro systems. The mathematical methods needed to describe all quantum phenomena mentioned above were also the subject of intense studies in the end of the last, and beginning of the new, century. In this section of CAMOP 'Mathematical Methods of Studying Physical Phenomena' new results and new trends in the rapidly developing domain of quantum (and classical) physics are presented. Among the particular topics under discussion there are some reviews on the problems of dynamical invariants and their relations with symmetries of the physical systems. In fact, this is a very old problem of both classical and quantum systems, e.g. the systems of parametric oscillators with time-dependent parameters, like Ermakov systems, which have specific constants of motion depending linearly or quadratically on the oscillator positions and momenta. Such dynamical invariants play an important role in studying the dynamical Casimir effect, the essence of the effect being the creation of photons from the vacuum in a cavity with moving boundaries due to the presence of purely quantum fluctuations of the electromagnetic field in the vacuum. It is remarkable that this effect was recently observed experimentally. The other new direction in developing the mathematical approach in physics is quantum tomography that provides a new vision of

  11. Ten Inquiry Methods Used in Curriculum Studies.

    ERIC Educational Resources Information Center

    Short, Edmund C.

    Ten different methods of inquiry are outlined in this overview of research methodologies currently being employed in the field of curriculum studies: (1) philosophical, (2) historical, (3) scientific, (4) artistic, (5) moral, (6) religious, (7) interpretive, (8) instrumental, (9) deliberative, and (10) action oriented. Each of the 10 methods is…

  12. Critical Appraisal of Mixed Methods Studies

    ERIC Educational Resources Information Center

    Heyvaert, Mieke; Hannes, Karin; Maes, Bea; Onghena, Patrick

    2013-01-01

    In several subdomains of the social, behavioral, health, and human sciences, research questions are increasingly answered through mixed methods studies, combining qualitative and quantitative evidence and research elements. Accordingly, the importance of including those primary mixed methods research articles in systematic reviews grows. It is…

  13. Diffusion of Bevacizumab Across Oncology Practices: An Observational Study.

    PubMed

    Keating, Nancy L; Huskamp, Haiden A; Schrag, Deborah; McWilliams, John M; McNeil, Barbara J; Landon, Bruce E; Chernew, Michael E; Normand, Sharon-Lise T

    2018-01-01

    Technological advances can improve care and outcomes but are a primary driver of health care spending growth. Understanding diffusion and use of new oncology therapies is important, given substantial increases in prices and spending on such treatments. Examine diffusion of bevacizumab, a novel (in 2004) and high-priced biologic cancer therapy, among US oncology practices during 2005-2012 and assess variation in use across practices. Population-based observational study. A total of 2329 US practices providing cancer chemotherapy. Random 20% sample of 236,304 Medicare fee-for-service beneficiaries aged above 65 years in 2004-2012 undergoing infused chemotherapy for cancer. Diffusion of bevacizumab (cumulative time to first use and 10% use) in practices, variation in use across practices overall and by higher versus lower-value use. We used hierarchical models with practice random effects to estimate the between-practice variation in the probability of receiving bevacizumab and to identify factors associated with use. We observed relatively rapid diffusion of bevacizumab, particularly in independent practices and larger versus smaller practices. We observed substantial variation in use; the adjusted odds ratio (95% confidence interval) of bevacizumab use was 2.90 higher (2.73-3.08) for practices 1 SD above versus one standard deviation below the mean. Variation was less for higher-value [odds ratio=2.72 (2.56-2.89)] than lower-value uses [odds ratio=3.61 (3.21-4.06)]. Use of bevacizumab varied widely across oncology practices, particularly for lower-value indications. These findings suggest that interventions targeted to practices have potential for decreasing low-value use of high-cost cancer therapies.

  14. An Observation Capability Semantic-Associated Approach to the Selection of Remote Sensing Satellite Sensors: A Case Study of Flood Observations in the Jinsha River Basin

    PubMed Central

    Hu, Chuli; Li, Jie; Lin, Xin

    2018-01-01

    Observation schedules depend upon the accurate understanding of a single sensor’s observation capability and the interrelated observation capability information on multiple sensors. The general ontologies for sensors and observations are abundant. However, few observation capability ontologies for satellite sensors are available, and no study has described the dynamic associations among the observation capabilities of multiple sensors used for integrated observational planning. This limitation results in a failure to realize effective sensor selection. This paper develops a sensor observation capability association (SOCA) ontology model that is resolved around the task-sensor-observation capability (TSOC) ontology pattern. The pattern is developed considering the stimulus-sensor-observation (SSO) ontology design pattern, which focuses on facilitating sensor selection for one observation task. The core aim of the SOCA ontology model is to achieve an observation capability semantic association. A prototype system called SemOCAssociation was developed, and an experiment was conducted for flood observations in the Jinsha River basin in China. The results of this experiment verified that the SOCA ontology based association method can help sensor planners intuitively and accurately make evidence-based sensor selection decisions for a given flood observation task, which facilitates efficient and effective observational planning for flood satellite sensors. PMID:29883425

  15. An Observation Capability Semantic-Associated Approach to the Selection of Remote Sensing Satellite Sensors: A Case Study of Flood Observations in the Jinsha River Basin.

    PubMed

    Hu, Chuli; Li, Jie; Lin, Xin; Chen, Nengcheng; Yang, Chao

    2018-05-21

    Observation schedules depend upon the accurate understanding of a single sensor’s observation capability and the interrelated observation capability information on multiple sensors. The general ontologies for sensors and observations are abundant. However, few observation capability ontologies for satellite sensors are available, and no study has described the dynamic associations among the observation capabilities of multiple sensors used for integrated observational planning. This limitation results in a failure to realize effective sensor selection. This paper develops a sensor observation capability association (SOCA) ontology model that is resolved around the task-sensor-observation capability (TSOC) ontology pattern. The pattern is developed considering the stimulus-sensor-observation (SSO) ontology design pattern, which focuses on facilitating sensor selection for one observation task. The core aim of the SOCA ontology model is to achieve an observation capability semantic association. A prototype system called SemOCAssociation was developed, and an experiment was conducted for flood observations in the Jinsha River basin in China. The results of this experiment verified that the SOCA ontology based association method can help sensor planners intuitively and accurately make evidence-based sensor selection decisions for a given flood observation task, which facilitates efficient and effective observational planning for flood satellite sensors.

  16. Yogurt and Diabetes: Overview of Recent Observational Studies.

    PubMed

    Salas-Salvadó, Jordi; Guasch-Ferré, Marta; Díaz-López, Andrés; Babio, Nancy

    2017-07-01

    The effects of dairy consumption on the prevention of type 2 diabetes remain controversial and depend on the dairy subtype. Yogurt intake has received special attention because its association with health benefits is more consistent than that of other types of dairy products. In the present article, we review those observational studies that evaluated the association between yogurt consumption and type 2 diabetes. We also discuss the possible mechanisms involved in these associations. We found that 13 prospective studies evaluated the association between yogurt intake and type 2 diabetes, most of which showed an inverse association between the frequency of yogurt consumption and the risk of diabetes. In addition to the scientific evidence accumulated from individual prospective studies, several meta-analyses have shown that yogurt consumption has a potential role in diabetes prevention. The most recent analysis shows a 14% lower risk of type 2 diabetes when yogurt consumption was 80-125 g/d compared with no yogurt consumption. The intake of fermented dairy products, especially yogurt, has been inversely associated with variables of glucose metabolism. Yogurt may have probiotic effects that could modulate glucose metabolism. We conclude that yogurt consumption, in the context of a healthy dietary pattern, may reduce the risk of type 2 diabetes in healthy and older adults at high cardiovascular risk. Large-scale intervention studies and randomized clinical trials are warranted to determine if yogurt consumption has beneficial effects on insulin sensitivity and reduces the risk of type 2 diabetes. © 2017 American Society for Nutrition.

  17. Arctic Sea ice studies with passive microwave satellite observations

    NASA Technical Reports Server (NTRS)

    Cavalieri, D. J.

    1988-01-01

    The objectives of this research are: (1) to improve sea ice concentration determinations from passive microwave space observations; (2) to study the role of Arctic polynyas in the production of sea ice and the associated salinization of Arctic shelf water; and (3) to study large scale sea ice variability in the polar oceans. The strategy is to analyze existing data sets and data acquired from both the DMSP SSM/I and recently completed aircraft underflights. Special attention will be given the high resolution 85.5 GHz SSM/I channels for application to thin ice algorithms and processes studies. Analysis of aircraft and satellite data sets is expected to provide a basis for determining the potential of the SSM/I high frequency channels for improving sea ice algorithms and for investigating oceanic processes. Improved sea ice algorithms will aid the study of Arctic coastal polynyas which in turn will provide a better understanding of the role of these polynyas in maintaining the Arctic watermass structure. Analysis of satellite and archived meteorological data sets will provide improved estimates of annual, seasonal and shorter-term sea ice variability.

  18. Intrauterine temperature during intrapartum amnioinfusion: a prospective observational study.

    PubMed

    Tomlinson, T M; Schaecher, C; Sadovsky, Y; Gross, G

    2012-07-01

    To determine the influence of routine intrapartum amnioinfusion (AI) on intrauterine temperature. Prospective observational study. Maternity unit, Barnes Jewish Hospital, St Louis, MO, USA. Forty women with singleton gestations and an indication for intrapartum intrauterine pressure catheter placement. Using a temperature probe, we digitally recorded intrauterine temperature every 10 minutes during labour. Amnioinfusion was administered according to a standard protocol using saline equilibrated to the ambient temperature. Mean intrauterine temperature during labour. Participants were monitored for a mean of 280 minutes (range 20-820). A total of 164 intrauterine temperature readings in the AI cohort were compared with 797 control measurements. When compared with controls, we observed a lower intrauterine temperature in the AI cohort (36.4 versus 37.4°C, P<0.01). More measurements in the AI cohort were recorded in the presence of intrapartum fever (40% versus 30%). A subgroup analysis of measurements recorded in afebrile parturients revealed an even greater effect of AI (1.5°C decrease, 37.3 versus 35.8°C, P<0.01). Routine intrapartum AI using saline equilibrated to a mean ambient temperature of 25.0°C reduces intrauterine temperature and may thereby affect fetal core temperature. © 2012 The Authors BJOG An International Journal of Obstetrics and Gynaecology © 2012 RCOG.

  19. Six-month observational study of prompted stair climbing.

    PubMed

    Kerr, J; Eves, F; Carroll, D

    2001-11-01

    Despite strong evidence that prompts at the point of choice between escalators and stairs encourage stair use, the long-term effects of stair prompts have not yet been investigated. Presented here are the results of a 6-month observational study of prompted stair climbing. Escalator and adjacent stair use were monitored in a shopping mall in the Midlands region of the United Kingdom. Participants were coded for gender, age, and ethnicity. A 2-week baseline period was followed by a 12-week intervention using motivating messages on the stair risers. Follow-up data were also collected for 2 weeks immediately after the removal of the banners and 6 weeks later. A total of 45,361 escalator/stair-choice observations were made. Stair use increased significantly during the intervention period and, when the banners were removed, remained higher than at baseline. There were also significant interactions with time across the different population groups. The full public health benefits of increasing physical activity levels can only be realized if the activity is sustained. These results demonstrate that stair-riser banners can elicit a sustained increase in stair use and, even when the banners were withdrawn, overall stair use remained higher than at baseline. Copyright 2001 American Health Foundation and Academic Press.

  20. Providers' response to child eating behaviors: A direct observation study.

    PubMed

    Tovar, Alison; Vaughn, Amber E; Fallon, Megan; Hennessy, Erin; Burney, Regan; Østbye, Truls; Ward, Dianne S

    2016-10-01

    Child care providers play an important role in feeding young children, yet little is known about children's influence on providers' feeding practices. This qualitative study examines provider and child (18 months -4 years) feeding interactions. Trained data collectors observed 200 eating occasions in 48 family child care homes and recorded providers' responses to children's meal and snack time behaviors. Child behaviors initiating provider feeding practices were identified and practices were coded according to higher order constructs identified in a recent feeding practices content map. Analysis examined the most common feeding practices providers used to respond to each child behavior. Providers were predominately female (100%), African-American (75%), and obese (77%) and a third of children were overweight/obese (33%). Commonly observed child behaviors were: verbal and non-verbal refusals, verbal and non-verbal acceptance, being "all done", attempts for praise/attention, and asking for seconds. Children's acceptance of food elicited more autonomy supportive practices vs. coercive controlling. Requests for seconds was the most common behavior, resulting in coercive controlling practices (e.g., insisting child eat certain food or clean plate). Future interventions should train providers on responding to children's behaviors and helping children become more aware of internal satiety and hunger cues. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Strengthening the Reporting of Observational Studies in Epidemiology (STROBE): Explanation and Elaboration

    PubMed Central

    Vandenbroucke, Jan P; von Elm, Erik; Altman, Douglas G; Gøtzsche, Peter C; Mulrow, Cynthia D; Pocock, Stuart J; Poole, Charles; Schlesselman, James J; Egger, Matthias

    2007-01-01

    Much medical research is observational. The reporting of observational studies is often of insufficient quality. Poor reporting hampers the assessment of the strengths and weaknesses of a study and the generalisability of its results. Taking into account empirical evidence and theoretical considerations, a group of methodologists, researchers, and editors developed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) recommendations to improve the quality of reporting of observational studies. The STROBE Statement consists of a checklist of 22 items, which relate to the title, abstract, introduction, methods, results and discussion sections of articles. Eighteen items are common to cohort studies, case-control studies and cross-sectional studies and four are specific to each of the three study designs. The STROBE Statement provides guidance to authors about how to improve the reporting of observational studies and facilitates critical appraisal and interpretation of studies by reviewers, journal editors and readers. This explanatory and elaboration document is intended to enhance the use, understanding, and dissemination of the STROBE Statement. The meaning and rationale for each checklist item are presented. For each item, one or several published examples and, where possible, references to relevant empirical studies and methodological literature are provided. Examples of useful flow diagrams are also included. The STROBE Statement, this document, and the associated Web site (http://www.strobe-statement.org/) should be helpful resources to improve reporting of observational research. PMID:17941715

  2. Strengthening the Reporting of Observational Studies in Epidemiology (STROBE): explanation and elaboration.

    PubMed

    Vandenbroucke, Jan P; von Elm, Erik; Altman, Douglas G; Gøtzsche, Peter C; Mulrow, Cynthia D; Pocock, Stuart J; Poole, Charles; Schlesselman, James J; Egger, Matthias

    2014-12-01

    Much medical research is observational. The reporting of observational studies is often of insufficient quality. Poor reporting hampers the assessment of the strengths and weaknesses of a study and the generalisability of its results. Taking into account empirical evidence and theoretical considerations, a group of methodologists, researchers, and editors developed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) recommendations to improve the quality of reporting of observational studies. The STROBE Statement consists of a checklist of 22 items, which relate to the title, abstract, introduction, methods, results and discussion sections of articles. Eighteen items are common to cohort studies, case-control studies and cross-sectional studies and four are specific to each of the three study designs. The STROBE Statement provides guidance to authors about how to improve the reporting of observational studies and facilitates critical appraisal and interpretation of studies by reviewers, journal editors and readers. This explanatory and elaboration document is intended to enhance the use, understanding, and dissemination of the STROBE Statement. The meaning and rationale for each checklist item are presented. For each item, one or several published examples and, where possible, references to relevant empirical studies and methodological literature are provided. Examples of useful flow diagrams are also included. The STROBE Statement, this document, and the associated Web site (http://www.strobe-statement.org/) should be helpful resources to improve reporting of observational research. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. Simultaneous observation of cavitation bubbles generated in biological tissue by high-speed optical and acoustic imaging methods

    NASA Astrophysics Data System (ADS)

    Suzuki, Kai; Iwasaki, Ryosuke; Takagi, Ryo; Yoshizawa, Shin; Umemura, Shin-ichiro

    2017-07-01

    Acoustic cavitation bubbles are useful for enhancing the heating effect in high-intensity focused ultrasound (HIFU) treatment. Many studies were conducted to investigate the behavior of such bubbles in tissue-mimicking materials, such as a transparent gel phantom; however, the detailed behavior in tissue was still unclear owing to the difficulty in optical observation. In this study, a new biological phantom was developed to observe cavitation bubbles generated in an optically shallow area of tissue. Two imaging methods, high-speed photography using light scattering and high-speed ultrasonic imaging, were used for detecting the behavior of the bubbles simultaneously. The results agreed well with each other for the area of bubble formation and the temporal change in the region of bubbles, suggesting that both methods are useful for visualizing the bubbles.

  4. X-Ray Phantom Development For Observer Performance Studies

    NASA Astrophysics Data System (ADS)

    Kelsey, C. A.; Moseley, R. D.; Mettler, F. A.; Parker, T. W.

    1981-07-01

    The requirements for radiographic imaging phantoms for observer performance testing include realistic tasks which mimic at least some portion of the diagnostic examination presented in a setting which approximates clinically derived images. This study describes efforts to simulate chest and vascular diseases for evaluation of conventional and digital radiographic systems. Images of lung nodules, pulmonary infiltrates, as well as hilar and mediastinal masses are generated with a conventional chest phantom to make up chest disease test series. Vascular images are simulated by hollow tubes embedded in tissue density plastic with widening and narrowing added to mimic aneurysms and stenoses. Both sets of phantoms produce images which allow simultaneous determination of true positive and false positive rates as well as complete ROC curves.

  5. Traction force during vacuum extraction: a prospective observational study.

    PubMed

    Pettersson, K; Ajne, J; Yousaf, K; Sturm, D; Westgren, M; Ajne, G

    2015-12-01

    To investigate the traction force employed during vacuum extractions. Observational cross-sectional study. Obstetric Department, Karolinska University Hospital, Sweden, and the Swedish National Congress of Obstetrics and Gynaecology, 2013. Two hundred women with vacuum extraction at term and 130 obstetricians participating in a simulated setting. In a normal clinical setting, we used a specially adapted device to measure and record the force used to undertake vacuum extraction. In a subsequent part of the study, the force employed for vacuum extraction by a group of obstetricians in a fictive setting was estimated and objectively measured. Applied force during vacuum extraction in relation to the estimated level of difficulty in the delivery; perinatal diagnoses of asphyxia or head trauma; estimated force compared with objectively measured force employed in the fictive setting. The median (minimum-maximum) peak forces for minimum, average and excessive vacuum extraction in the clinical setting were 176 N (5-360 N), 225 N (115-436 N), and 241 N (164-452 N), respectively. In 34% of cases a force in excess of 216 N was employed. There was no correlation between the umbilical arterial pH at delivery and the traction force employed during extraction. Four cases of mild hypoxic ischaemic encephalopathy were observed, three of which were associated with a delivery whereby excessive traction force was employed during the vacuum extraction. In the fictive setting, the actual exerted force was twice the quantitative estimation. The measured forces in the clinical setting were four times higher than that estimated in the fictive setting. Higher than expected levels of traction force were used for vacuum extraction delivery. As obstetricians tend to underestimate the force applied during vacuum extraction, objective measurement with instantaneous feedback may be valuable in raising awareness. © 2015 Royal College of Obstetricians and Gynaecologists.

  6. Towards a standardized method to assess straylight in earth observing optical instruments

    NASA Astrophysics Data System (ADS)

    Caron, J.; Taccola, M.; Bézy, J.-L.

    2017-09-01

    Straylight is a spurious effect that can seriously degrade the radiometric accuracy achieved by Earth observing optical instruments, as a result of the high contrast in the observed Earth radiance scenes and spectra. It is considered critical for several ESA missions such as Sentinel-5, FLEX and potential successors to CarbonSat. Although it is traditionally evaluated by Monte-Carlo simulations performed with commercial softwares (e.g. ASAP, Zemax, LightTools), semi-analytical approximate methods [1,2] have drawn some interest in recent years due to their faster computing time and the greater insight they provide in straylight mechanisms. They cannot replace numerical simulations, but may be more advantageous in contexts where many iterations are needed, for instance during the early phases of an instrument design.

  7. Plate measurement techniques and reduction methods used by the West German satellite observers, and resulting consequences for the observation

    NASA Technical Reports Server (NTRS)

    Deker, H.

    1971-01-01

    The West German tracking stations are equipped with ballistic cameras. Plate measurement and plate reduction must therefore follow photogrammetric methods. Approximately 100 star positions and 200 satellite positions are measured on each plate. The mathematical model for spatial rotation of the bundle of rays is extended by including terms for distortion and internal orientation of the camera as well as by providing terms for refraction which are computed for the measured coordinates of the star positions on the plate. From the measuring accuracy of the plate coordinates it follows that the timing accuracy for the exposures has to be about one millisecond, in order to obtain a homogeneous system.

  8. Pediatric fractures through the eyes of parents: an observational study.

    PubMed

    Sofu, Hakan; Gursu, Sarper; Kockara, Nizamettin; Issin, Ahmet; Oner, Ali; Camurcu, Yalkin

    2015-01-01

    The present study is an observational cross-sectional study. The main purpose of this research was to analyze the perception and behaviors of parents in a series of pediatric upper extremity fracture cases. Hundred and seventeen patients younger than 12 years who were conservatively treated for the upper extremity fracture were included in our study. Parents of the patients were requested to answer a family-centered questionnaire related to their child's fracture and its treatment. When the parents were asked whether they believe casting would be sufficient or not as the treatment of their child's fracture, 84.6% answered 'yes', 13.7% answered 'I am not sure,' and 1.7% answered 'no.' Sixty-four of the parents were not worried about any residual defect in joint or extremity functions related to fracture, whereas 21 were worried and 32 were not sure on this. The rate of searching further information about the child's fracture was 34.2% and the mostly used source was the Internet. Twenty-eight of the 117 respondents (23.9%) emphasized that they would reduce the time their child spend outside the home at least for a while after the removal of cast. When conservatively treating a child's fracture, physicians dealing with traumatology should always consider the parents' perception and behaviors as critically important.

  9. 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.

  10. Observational study of sleep disturbances in advanced cancer.

    PubMed

    Davies, Andrew Neil; Patel, Shuchita D; Gregory, Amanda; Lee, Bernadette

    2017-12-01

    To determine the prevalence of nightmares, sleep terrors and vivid dreams in patients with advanced cancer (and the factors associated with them in this group of patients). The study was a multicentre, prospective observational study. Participants were patients with locally advanced/metastatic cancer, who were under the care of a specialist palliative care team. Data were collected on demographics, cancer diagnosis, cancer treatment, current medication, performance status, sleep quality (Pittsburgh Sleep Quality Index), dreams and nightmares, and physical and psychological symptoms (Memorial Symptom Assessment Scale-Short Form). 174 patients completed the study. Sleep quality was poor in 70.5% participants and was worse in younger patients and in inpatients (hospital, hospice). 18% of patients reported nightmares, 8% sleep terrors and 34% vivid dreams. Nightmares were associated with poor sleep quality and greater sleep disturbance; nightmares were also associated with greater physical and psychological burden. Nightmares (and vivid dreams) were not associated with the use of opioid analgesics. Nightmares do not seem to be especially common in patients with advanced cancer, and when they do occur, there is often an association with sleep disturbance, and/or physical and psychological burden. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  11. Molecular Carbon in the Galaxy: Laboratory and Observational Studies

    NASA Technical Reports Server (NTRS)

    Saykally, Richard James

    2003-01-01

    In a collaboration with the Mats Larsson group from Stockholm, we carried out a new measurement of the rate of dissociative recombination of H(sup *, sub j), using a new pulsed supersonic beam source of rotationally cold H(sup *, sub j). This source was first designed and characterized in our lab by IR cavity ringdown spectroscopy, determining a rotationaYtranslationa1 temperature of 20-60K, depending on conditions. This new source was then taken to Stockholm for the recombination rate studies at the CRYRING storage ring. The recombination rate constant measured against temperature yields values consistent with the most recent calculations, whereas previous experimental measurements varied over a range of 10(exp 4) and were poor agreement with theory. This is a crucial achievement for understanding the ion chemistry of diffuse clouds. Moreover, this result in combination with recent observations implies a greatly enhanced (factor of 40) cosmic ray ionization rate in a diffuse cloud (zeta Persei) relative to previous studies. The implications of this are discussed in our recent Nature paper. An enhanced cosmic-ray flux towards zeta Persei inferred from a laboratory study of the H(sup *, sub j)-e(sup -) recombination rate.

  12. [Clinical observation on nanometer acupoint mounting method for alleviation of myospasm complicated by spinal injury].

    PubMed

    Zhang, Su-Jie; Si, Tong; Li, Zhi

    2008-11-01

    To observe clinical effect of nanometer acupoint mounting method for alleviation of myospasm complicated by spinal injury. Sixty cases were randomly divided into an observation group and a control group, 30 cases in each group. The observation group were treated by nanometer mounting at 4 Jiaji (EX-B 2) points each on both sides of the affected spine and Shenshu (BL 23), Shangliao (BL 31), Ciliao (BL 32), Yang-lingquan (GB 34), Xuanzhong (GB 39); and the control group by mounting zinc oxide sticking tablets at the above acupoints. The mounting was replaced once each two days, 7 times constituting one course. One week and one month after the end of 3 courses, their results were recorded, respectively. Before treatment, there was no significant difference between the two groups in grades of the myospasm degree (P > 0.05). One week after the end of treatment, 15 cases were grade I of myospasm, 9 cases were grade II, 5 cases were grade III and 1 case was grade IV in the observation group, and 1 cases grade I, 7 cases grade II, 14 cases grade III, 8 cases grade IV in the control group. Ridit analysis on the data indicated that there were significant differences before and after treatment in the myospasm degree (P < 0.01) and between the two groups after treatment (P < 0.01). One month after the end of treatment, the results were similar to those one week after the end of treatment. Nanometer acupoint mounting method is a new one for alleviation of myospasm complicated by spinal injury, with convenience, safety and no side effect.

  13. 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.

  14. An Observationally-Centred Method to Quantify the Changing Shape of Local Temperature Distributions

    NASA Astrophysics Data System (ADS)

    Chapman, S. C.; Stainforth, D. A.; Watkins, N. W.

    2014-12-01

    For climate sensitive decisions and adaptation planning, guidance on how local climate is changing is needed at the specific thresholds relevant to particular impacts or policy endeavours. This requires the quantification of how the distributions of variables, such as daily temperature, are changing at specific quantiles. These temperature distributions are non-normal and vary both geographically and in time. We present a method[1,2] for analysing local climatic time series data to assess which quantiles of the local climatic distribution show the greatest and most robust changes. We have demonstrated this approach using the E-OBS gridded dataset[3] which consists of time series of local daily temperature across Europe over the last 60 years. Our method extracts the changing cumulative distribution function over time and uses a simple mathematical deconstruction of how the difference between two observations from two different time periods can be assigned to the combination of natural statistical variability and/or the consequences of secular climate change. The change in temperature can be tracked at a temperature threshold, at a likelihood, or at a given return time, independently for each geographical location. Geographical correlations are thus an output of our method and reflect both climatic properties (local and synoptic), and spatial correlations inherent in the observation methodology. We find as an output many regionally consistent patterns of response of potential value in adaptation planning. For instance, in a band from Northern France to Denmark the hottest days in the summer temperature distribution have seen changes of at least 2°C over a 43 year period; over four times the global mean change over the same period. We discuss methods to quantify the robustness of these observed sensitivities and their statistical likelihood. This approach also quantifies the level of detail at which one might wish to see agreement between climate models and

  15. Method for observation of deembedded sections of fish gonad by scanning electron microscopy

    NASA Astrophysics Data System (ADS)

    Mao, Lian-Ju

    2000-09-01

    This article reports a method for examining the intracellular structure of fish gonads using a scanning electron microscope(SEM). The specimen preparation procedure is similar to that for transmission electron microscopy wherein samples cut into semi-thin sections are fixed and embedded in plastic. The embedment matrix was removed by solvents. Risen-free specimens could be observed by SEM. The morphology of matured sperms in the gonad was very clear, and the oocyte internal structures appeared in three-dimensional images. Spheroidal nucleoli and yolk vesicles and several bundles of filaments adhered on the nucleoli could be viewed by SEM for the first time.

  16. Types of propagation of radio waves of the decameter range, according to observations by the OBS method on Cuba--Soviet Union paths

    SciTech Connect

    Berdeyans, D.; Bocharov, V.I.; Lobachevskii, L.A.

    Ionosphere observations by the OBS method were performed to study ionospheric conditions under which radio waves in the decameter range propagate on Cuba--Soviet Union paths. The results of observations in the summer of 1973 are reported. The distance--frequency and distance--time characteristics of back-scattered signals in the sounding direction for each day of observation are discussed. (JFP)

  17. Validation of Satellite-Based Objective Overshooting Cloud-Top Detection Methods Using CloudSat Cloud Profiling Radar Observations

    NASA Technical Reports Server (NTRS)

    Bedka, Kristopher M.; Dworak, Richard; Brunner, Jason; Feltz, Wayne

    2012-01-01

    Two satellite infrared-based overshooting convective cloud-top (OT) detection methods have recently been described in the literature: 1) the 11-mm infrared window channel texture (IRW texture) method, which uses IRW channel brightness temperature (BT) spatial gradients and thresholds, and 2) the water vapor minus IRW BT difference (WV-IRW BTD). While both methods show good performance in published case study examples, it is important to quantitatively validate these methods relative to overshooting top events across the globe. Unfortunately, no overshooting top database currently exists that could be used in such study. This study examines National Aeronautics and Space Administration CloudSat Cloud Profiling Radar data to develop an OT detection validation database that is used to evaluate the IRW-texture and WV-IRW BTD OT detection methods. CloudSat data were manually examined over a 1.5-yr period to identify cases in which the cloud top penetrates above the tropopause height defined by a numerical weather prediction model and the surrounding cirrus anvil cloud top, producing 111 confirmed overshooting top events. When applied to Moderate Resolution Imaging Spectroradiometer (MODIS)-based Geostationary Operational Environmental Satellite-R Series (GOES-R) Advanced Baseline Imager proxy data, the IRW-texture (WV-IRW BTD) method offered a 76% (96%) probability of OT detection (POD) and 16% (81%) false-alarm ratio. Case study examples show that WV-IRW BTD.0 K identifies much of the deep convective cloud top, while the IRW-texture method focuses only on regions with a spatial scale near that of commonly observed OTs. The POD decreases by 20% when IRW-texture is applied to current geostationary imager data, highlighting the importance of imager spatial resolution for observing and detecting OT regions.

  18. Time-of-Flight Measurements as a Possible Method to Observe Anyonic Statistics

    NASA Astrophysics Data System (ADS)

    Umucalılar, R. O.; Macaluso, E.; Comparin, T.; Carusotto, I.

    2018-06-01

    We propose a standard time-of-flight experiment as a method for observing the anyonic statistics of quasiholes in a fractional quantum Hall state of ultracold atoms. The quasihole states can be stably prepared by pinning the quasiholes with localized potentials and a measurement of the mean square radius of the freely expanding cloud, which is related to the average total angular momentum of the initial state, offers direct signatures of the statistical phase. Our proposed method is validated by Monte Carlo calculations for ν =1 /2 and 1 /3 fractional quantum Hall liquids containing a realistic number of particles. Extensions to quantum Hall liquids of light and to non-Abelian anyons are briefly discussed.

  19. Characterizing Suicide in Toronto: An Observational Study and Cluster Analysis

    PubMed Central

    Sinyor, Mark; Schaffer, Ayal; Streiner, David L

    2014-01-01

    Objective: To determine whether people who have died from suicide in a large epidemiologic sample form clusters based on demographic, clinical, and psychosocial factors. Method: We conducted a coroner’s chart review for 2886 people who died in Toronto, Ontario, from 1998 to 2010, and whose death was ruled as suicide by the Office of the Chief Coroner of Ontario. A cluster analysis using known suicide risk factors was performed to determine whether suicide deaths separate into distinct groups. Clusters were compared according to person- and suicide-specific factors. Results: Five clusters emerged. Cluster 1 had the highest proportion of females and nonviolent methods, and all had depression and a past suicide attempt. Cluster 2 had the highest proportion of people with a recent stressor and violent suicide methods, and all were married. Cluster 3 had mostly males between the ages of 20 and 64, and all had either experienced recent stressors, suffered from mental illness, or had a history of substance abuse. Cluster 4 had the youngest people and the highest proportion of deaths by jumping from height, few were married, and nearly one-half had bipolar disorder or schizophrenia. Cluster 5 had all unmarried people with no prior suicide attempts, and were the least likely to have an identified mental illness and most likely to leave a suicide note. Conclusions: People who die from suicide assort into different patterns of demographic, clinical, and death-specific characteristics. Identifying and studying subgroups of suicides may advance our understanding of the heterogeneous nature of suicide and help to inform development of more targeted suicide prevention strategies. PMID:24444321

  20. Satellite Observation Systems for Polar Climate Change Studies

    NASA Technical Reports Server (NTRS)

    Comiso, Josefino C.

    2012-01-01

    The key observational tools for detecting large scale changes of various parameters in the polar regions have been satellite sensors. The sensors include passive and active satellite systems in the visible, infrared and microwave frequencies. The monitoring started with Tiros and Nimbus research satellites series in the 1970s but during the period, not much data was stored digitally because of limitations and cost of the needed storage systems. Continuous global data came about starting with the launch of ocean color, passive microwave, and thermal infrared sensors on board Nimbus-7 and Synthetic Aperture Radar, Radar Altimeter and Scatterometer on board SeaSat satellite both launched in 1978. The Nimbus-7 lasted longer than expected and provided about 9 years of useful data while SeaSat quit working after 3 months but provided very useful data that became the baseline for follow-up systems with similar capabilities. Over the years, many new sensors were launched, some from Japan Aeronautics and Space Agency (JAXA), some from the European Space Agency (ESA) and more recently, from RuSSia, China, Korea, Canada and India. For polar studies, among the most useful sensors has been the passive microwave sensor which provides day/night and almost all weather observation of the surface. The sensor provide sea surface temperature, precipitation, wind, water vapor and sea ice concentration data that have been very useful in monitoring the climate of the region. More than 30 years of such data are now available, starting with the Scanning Multichannel Microwave Radiometer (SMMR) on board the Nimbus-7, the Special Scanning Microwave/Imager (SSM/I) on board a Defense Meteorological Satellite Program (DMSP) and the Advanced Microwave Scanning Radiometer on board the EOS/ Aqua satellite. The techniques that have been developed to derive geophysical parameters from data provided by these and other sensors and associated instrumental and algorithm errors and validation techniques

  1. Oral implications of the vegan diet: observational study.

    PubMed

    Laffranchi, L; Zotti, F; Bonetti, S; Dalessandri, D; Fontana, P

    2010-01-01

    The aim of this study was to investigate oral changes in subjects who have assumed a vegan diet for a long time (at least 18 months), that is to say, a diet completely lacking in meat and animal derivatives. A sample of 15 subjects was analyzed, all from northern Italy and aged 24 to 60 year, composed of 11 men and 4 women who had been following a vegan diet for a minimum of 18 months to a maximum of 20 years. In parallel with the study sample, a control group (15 subjects) with the same criteria of age, sex, and place of origin all following an omnivorous diet was chosen. The sample answered a questionnaire that investigated their eating habits, the frequency with which they eat meals, the main foodstuffs assumed, oral hygiene habits, and any painful symptomatology of the teeth or more general problems in the oral cavity. The sample was then subject to objective examination in which the saliva pH was measured and the teeth were checked for demineralization of the enamel, white spots, and caries (using KaVo DIAGNOdent) with particular attention being paid to the localization of these lesions, and lastly, sounding was carried out to detect any osseous defects and periodontal pockets. The study revealed greater incidence of demineralization and white spots in the vegan subjects compared to the omnivorous ones localized at the neck of the teeth and on the vestibular surfaces of dental elements (with the exception of the lower anterior group). The saliva pH, more acid in the omnivorous patients, ranged between four and six. Changes in oral conditions in both groups of subjects were observed. In order to research into the cause-effect relationship of the vegan diet on the oral cavity effectively, the sample needs to be studied for a longer period of time and the results re-evaluated.

  2. Beyond the traditional definition of breakthrough pain: an observational study.

    PubMed

    Gatti, Antonio; Gentili, Marta; Iorno, Vittorio; Mammucari, Massimo; Tufaro, Giuseppe; Lazzari, Marzia; Sabato, Alessandro Fabrizio

    2013-03-01

    Breakthrough pain (BTP) is traditionally defined as a transitory pain flare in opioid-treated patients with chronic background pain. This definition has, however, been challenged in recent years. This study aimed to analyze BTP prevalence in different pain conditions. This was a prospective, non-interventional, observational study conducted from June to September 2011 in two Italian pain treatment reference centres. Consecutive patients aged >18 years with oncological or non-oncological pain were eligible for this study; background pain was acute/ subacute (<3 months) or chronic (>3 months). The characteristics of pain were evaluated by means of a structured interview by physicians, and patients were asked to complete a dedicated clinical study form. The following outcomes were assessed: chronic pain duration (in patients with chronic pain), BTP prevalence, and number and severity of daily BTP episodes. All outcomes were assessed in four populations of patients with: (a) chronic oncological pain; (b) chronic non-oncological pain; (c) non-chronic oncological pain; (d) non-chronic non-oncological pain. The correlation between BTP and gender was also investigated. Of 1,270 patients with chronic pain, 1,086 had non-oncological pain (85.5%). Most patients (68.6%) with non-oncological pain were female (P = 0.001). Pain duration was significantly longer in non-oncological pain versus oncological pain groups (P = 0.002). BTP prevalence was lower in non-oncological patients (P < 0.001). No differences were reported in terms of number and severity of daily BTP episodes. BTP was more frequent in females with non-oncological pain (P = 0.04). Females had a significantly higher pain severity (P = 0.02) than males. BTP is frequently reported in patients who do not have BTP according to the traditional definition. BTP frequency and severity is similar in oncological and non-oncological pain.

  3. The Saturn Ring Observer: In situ studies of planetary rings

    NASA Astrophysics Data System (ADS)

    Nicholson, P. D.; Tiscareno, M. S.; Spilker, L. J.

    2010-12-01

    As part of the Planetary Science Decadal Survey recently undertaken by the NRC's Space Studies Board for the National Academy of Sciences, studies were commissioned for a number of potential missions to outer planet targets. One of these studies examined the technological feasibility of a mission to carry out in situ studies of Saturn's rings, from a spacecraft placed in a circular orbit above the ring plane: the Saturn Ring Observer. The technical findings and background are discussed in a companion poster by T. R. Spilker et al. Here we outline the science goals of such a mission. Most of the fundamental interactions in planetary rings occur on spatial scales that are unresolved by flyby or orbiter spacecraft. Typical particle sizes in the rings of Saturn are in the 1 cm - 10 m range, and average interparticle spacings are a few meters. Indirect evidence indicates that the vertical thickness of the rings is as little as 5 - 10 m, which implies a velocity dispersion of only a few mm/sec. Theories of ring structure and evolution depend on the unknown characteristics of interparticle collisions and on the size distribution of the ring particles. The SRO could provide direct measurements of both the coefficient of restitution -- by monitoring individual collisions -- and the particles’ velocity dispersion. High-resolution observations of individual ring particles should also permit estimates of their spin states. Numerical simulations of Saturn’s rings incorporating both collisions and self-gravity predict that the ring particles are not uniformly distributed, but are instead clustered into elongated structures referred to as “self-gravity wakes”, which are continually created and destroyed on an orbital timescale. Theory indicates that the average separation between wakes in the A ring is of order 30-100 m. Direct imaging of self-gravity wakes, including their formation and subsequent dissolution, would provide critical validation of these models. Other

  4. Observational Study on Safety of Prehospital BLS CPAP in Dyspnea.

    PubMed

    Sahu, Novneet; Matthews, Patrick; Groner, Kathryn; Papas, Mia A; Megargel, Ross

    2017-12-01

    Introduction Continuous positive airway pressure (CPAP) improves outcomes in patients with respiratory distress. Additional benefits are seen with CPAP application in the prehospital setting. Theoretical safety concerns regarding Basic Life Support (BLS) providers using CPAP exist. In Delaware's (USA) two-tiered Emergency Medical Service (EMS) system, BLS often arrives before Advanced Life Support (ALS). Hypothesis This study fills a gap in literature by evaluating the safety of CPAP applied by BLS prior to ALS arrival. This was a retrospective, observational study using Quality Assurance (QA) data collected from October 2009 through December 2012 throughout a state BLS CPAP pilot program; CPAP training was provided to BLS providers prior to participation. Collected data include pulse-oximetry (spO2), respiratory rate (RR), heart rate (HR), skin color, and Glasgow Coma Score (GCS) before and after CPAP application. Pre-CPAP and post-CPAP values were compared using McNemar's and t-tests. Advanced practitioners evaluated whether CPAP was correctly applied and monitored and whether the patient condition was "improved," "unchanged," or "worsened." Seventy-four patients received CPAP by BLS; CPAP was correctly indicated and applied for all 74 patients. Respiratory status and CPAP were appropriately monitored and documented in the majority of cases (98.6%). A total of 89.2% of patients improved and 4.1% worsened; CPAP significantly reduced the proportion of patients with SpO224, and cyanosis (P<.01). The GCS improved from mean (standard deviation [SD]) 13.9 (SD=1.9) to 14.1 (SD=1.9) after CPAP (mean difference [MD]=0.17; 95% CI, -0.49 to 0.83; P=.59). The HR decreased from 115.7 (SD=53) to 105.1 (SD=37) after CPAP (MD=-10.9; 95% CI, -3.2 to -18.6; P<.01). The SpO2 increased from 80.8% (SD=11.4) to 96.9% (SD=4.2) after CPAP (MD=17.8; 95% CI, 14.2-21.5; P<.01). The BLS providers were able to determine patients for whom CPAP was indicated, to apply it correctly, and to

  5. [Pregnancy-Associated Breast Cancer: An analytical observational study].

    PubMed

    Baulies, Sonia; Cusidó, Maite; Tresserra, Francisco; Rodríguez, Ignacio; Ubeda, Belén; Ara, Carmen; Fábregas, Rafael

    2014-03-04

    Pregnancy-associated breast cancer is defined as breast cancer diagnosed during pregnancy and up to one year postpartum. A retrospective, analytical, observational study comparing 56 cases of breast cancer and pregnancy (PABC) diagnosed 1976-2008 with 73 patients with breast cancer not associated with pregnancy (non-PABC) was performed. Demographic data, prognostic factors, treatment and survival were reviewed and compared. The prevalence of PABC in our center is 8.3/10,000. The highest frequency (62%) appeared during the postpartum period. The stages are higher in PABC, being 31.3% advanced (EIII and EIV) in PABC versus 13.3% in non-PABC (P < .05). Regarding prognostic factors, 27.3% in PABC had a tumoral grade 3 versus 15.8% of non-PABC. Among women with PABC, 33.3% had negative estrogen receptors, 48.7% negative progesterone receptors and 34.5% positive Her2Neu compared with 22.2, 24.1 and 31%, respectively of non-PABC patients. Finally, positive lymph nodes were found in 52.8% of PABC, versus 33.8% non-PABC (P < .05). Overall and disease-free survival rate at 5 years for PABC was 63.7 and 74.2%, respectively. The poorer survival observed is possibly due to the presence of adverse prognostic features such as lymph node metastases, negative hormone receptors, tumoral grade iii, as well as a delay in diagnosis with a higher rate of advanced stages. Copyright © 2012 Elsevier España, S.L. All rights reserved.

  6. Southeast Atmosphere Studies: Learning from Model-Observation Syntheses

    NASA Technical Reports Server (NTRS)

    Mao, Jingqiu; Carlton, Annmarie; Cohen, Ronald C.; Brune, William H.; Brown, Steven S.; Wolfe, Glenn M.; Jimenez, Jose L.; Pye, Havala O. T.; Ng, Nga Lee; Xu, Lu; hide

    2018-01-01

    Concentrations of atmospheric trace species in the United States have changed dramatically over the past several decades in response to pollution control strategies, shifts in domestic energy policy and economics, and economic development (and resulting emission changes) elsewhere in the world. Reliable projections of the future atmosphere require models to not only accurately describe current atmospheric concentrations, but to do so by representing chemical, physical and biological processes with conceptual and quantitative fidelity. Only through incorporation of the processes controlling emissions and chemical mechanisms that represent the key transformations among reactive molecules can models reliably project the impacts of future policy, energy and climate scenarios. Efforts to properly identify and implement the fundamental and controlling mechanisms in atmospheric models benefit from intensive observation periods, during which collocated measurements of diverse, speciated chemicals in both the gas and condensed phases are obtained. The Southeast Atmosphere Studies (SAS, including SENEX, SOAS, NOMADSS and SEAC4RS) conducted during the summer of 2013 provided an unprecedented opportunity for the atmospheric modeling community to come together to evaluate, diagnose and improve the representation of fundamental climate and air quality processes in models of varying temporal and spatial scales. This paper is aimed at discussing progress in evaluating, diagnosing and improving air quality and climate modeling using comparisons to SAS observations as a guide to thinking about improvements to mechanisms and parameterizations in models. The effort focused primarily on model representation of fundamental atmospheric processes that are essential to the formation of ozone, secondary organic aerosol (SOA) and other trace species in the troposphere, with the ultimate goal of understanding the radiative impacts of these species in the southeast and elsewhere. Here we

  7. Southeast Atmosphere Studies: learning from model-observation syntheses

    NASA Astrophysics Data System (ADS)

    Mao, Jingqiu; Carlton, Annmarie; Cohen, Ronald C.; Brune, William H.; Brown, Steven S.; Wolfe, Glenn M.; Jimenez, Jose L.; Pye, Havala O. T.; Ng, Nga Lee; Xu, Lu; McNeill, V. Faye; Tsigaridis, Kostas; McDonald, Brian C.; Warneke, Carsten; Guenther, Alex; Alvarado, Matthew J.; de Gouw, Joost; Mickley, Loretta J.; Leibensperger, Eric M.; Mathur, Rohit; Nolte, Christopher G.; Portmann, Robert W.; Unger, Nadine; Tosca, Mika; Horowitz, Larry W.

    2018-02-01

    Concentrations of atmospheric trace species in the United States have changed dramatically over the past several decades in response to pollution control strategies, shifts in domestic energy policy and economics, and economic development (and resulting emission changes) elsewhere in the world. Reliable projections of the future atmosphere require models to not only accurately describe current atmospheric concentrations, but to do so by representing chemical, physical and biological processes with conceptual and quantitative fidelity. Only through incorporation of the processes controlling emissions and chemical mechanisms that represent the key transformations among reactive molecules can models reliably project the impacts of future policy, energy and climate scenarios. Efforts to properly identify and implement the fundamental and controlling mechanisms in atmospheric models benefit from intensive observation periods, during which collocated measurements of diverse, speciated chemicals in both the gas and condensed phases are obtained. The Southeast Atmosphere Studies (SAS, including SENEX, SOAS, NOMADSS and SEAC4RS) conducted during the summer of 2013 provided an unprecedented opportunity for the atmospheric modeling community to come together to evaluate, diagnose and improve the representation of fundamental climate and air quality processes in models of varying temporal and spatial scales.This paper is aimed at discussing progress in evaluating, diagnosing and improving air quality and climate modeling using comparisons to SAS observations as a guide to thinking about improvements to mechanisms and parameterizations in models. The effort focused primarily on model representation of fundamental atmospheric processes that are essential to the formation of ozone, secondary organic aerosol (SOA) and other trace species in the troposphere, with the ultimate goal of understanding the radiative impacts of these species in the southeast and elsewhere. Here we

  8. Southeast Atmosphere Studies: learning from model-observation syntheses

    PubMed Central

    Mao, Jingqiu; Carlton, Annmarie; Cohen, Ronald C.; Brune, William H.; Brown, Steven S.; Wolfe, Glenn M.; Jimenez, Jose L.; Pye, Havala O. T.; Ng, Nga Lee; Xu, Lu; McNeill, V. Faye; Tsigaridis, Kostas; McDonald, Brian C.; Warneke, Carsten; Guenther, Alex; Alvarado, Matthew J.; de Gouw, Joost; Mickley, Loretta J.; Leibensperger, Eric M.; Mathur, Rohit; Nolte, Christopher G.; Portmann, Robert W.; Unger, Nadine; Tosca, Mika; Horowitz, Larry W.

    2018-01-01

    Concentrations of atmospheric trace species in the United States have changed dramatically over the past several decades in response to pollution control strategies, shifts in domestic energy policy and economics, and economic development (and resulting emission changes) elsewhere in the world. Reliable projections of the future atmosphere require models to not only accurately describe current atmospheric concentrations, but to do so by representing chemical, physical and biological processes with conceptual and quantitative fidelity. Only through incorporation of the processes controlling emissions and chemical mechanisms that represent the key transformations among reactive molecules can models reliably project the impacts of future policy, energy and climate scenarios. Efforts to properly identify and implement the fundamental and controlling mechanisms in atmospheric models benefit from intensive observation periods, during which collocated measurements of diverse, speciated chemicals in both the gas and condensed phases are obtained. The Southeast Atmosphere Studies (SAS, including SENEX, SOAS, NOMADSS and SEAC4RS) conducted during the summer of 2013 provided an unprecedented opportunity for the atmospheric modeling community to come together to evaluate, diagnose and improve the representation of fundamental climate and air quality processes in models of varying temporal and spatial scales. This paper is aimed at discussing progress in evaluating, diagnosing and improving air quality and climate modeling using comparisons to SAS observations as a guide to thinking about improvements to mechanisms and parameterizations in models. The effort focused primarily on model representation of fundamental atmospheric processes that are essential to the formation of ozone, secondary organic aerosol (SOA) and other trace species in the troposphere, with the ultimate goal of understanding the radiative impacts of these species in the southeast and elsewhere. Here we

  9. Why Rudolph’s nose is red: observational study

    PubMed Central

    van Kuijen, Anne-Marije; Milstein, Dan M J; Yürük, Koray; Folkow, Lars P; Fokkens, Wytske J; Blix, Arnoldus S

    2012-01-01

    Objective To characterise the functional morphology of the nasal microcirculation in humans in comparison with reindeer as a means of testing the hypothesis that the luminous red nose of Rudolph, one of the most well known reindeer pulling Santa Claus’s sleigh, is due to the presence of a highly dense and rich nasal microcirculation. Design Observational study. Setting Tromsø, Norway (near the North Pole), and Amsterdam, the Netherlands. Participants Five healthy human volunteers, two adult reindeer, and a patient with grade 3 nasal polyposis. Main outcome measures Architecture of the microvasculature of the nasal septal mucosa and head of the inferior turbinates, kinetics of red blood cells, and real time reactivity of the microcirculation to topical medicines. Results Similarities between human and reindeer nasal microcirculation were uncovered. Hairpin-like capillaries in the reindeers’ nasal septal mucosa were rich in red blood cells, with a perfused vessel density of 20 (SD 0.7) mm/mm2. Scattered crypt or gland-like structures surrounded by capillaries containing flowing red blood cells were found in human and reindeer noses. In a healthy volunteer, nasal microvascular reactivity was demonstrated by the application of a local anaesthetic with vasoconstrictor activity, which resulted in direct cessation of capillary blood flow. Abnormal microvasculature was observed in the patient with nasal polyposis. Conclusions The nasal microcirculation of reindeer is richly vascularised, with a vascular density 25% higher than that in humans. These results highlight the intrinsic physiological properties of Rudolph’s legendary luminous red nose, which help to protect it from freezing during sleigh rides and to regulate the temperature of the reindeer’s brain, factors essential for flying reindeer pulling Santa Claus’s sleigh under extreme temperatures. PMID:23247980

  10. Prognostic factors of Bell's palsy: prospective patient collected observational study.

    PubMed

    Fujiwara, Takashi; Hato, Naohito; Gyo, Kiyofumi; Yanagihara, Naoaki

    2014-07-01

    The purpose of this study was to evaluate various parameters potentially influencing poor prognosis in Bell's palsy and to assess the predictive value for Bell's palsy. A single-center prospective patient collected observation and validation study was conducted. To evaluate the correlation between patient characteristics and poor prognosis, we performed univariate and multivariate analyzes of age, gender, side of palsy, diabetes mellitus, hypertension, and facial grading score 1 week after onset. To evaluate the accuracy of the facial grading score, we prepared a receiver operating characteristic (ROC) curve and calculated the area under the ROC curve (AUROC). We also calculated sensitivity, specificity, positive/negative likelihood ratio, and positive/negative predictive value. We included Bell's palsy patients who attended Ehime University Hospital within 1 week after onset between 1977 and 2011. We excluded patients who were less than 15 years old and lost-to-follow-up within 6 months. The main outcome was defined as non-recovery at 6 months after onset. In total, 679 adults with Bell's palsy were included. The facial grading score at 1 week showed a correlation with non-recovery in the multivariate analysis, although age, gender, side of palsy, diabetes mellitus, and hypertension did not. The AUROC of the facial grading score was 0.793. The Y-system score at 1 week moderate accurately predicted non-recovery at 6 months in Bell's palsy.

  11. Treatment of Crohn's disease with cannabis: an observational study.

    PubMed

    Naftali, Timna; Lev, Lihi Bar; Yablecovitch, Doron; Yablekovitz, Doron; Half, Elisabeth; Konikoff, Fred M

    2011-08-01

    The marijuana plant cannabis is known to have therapeutic effects, including improvement of inflammatory processes. However, no report of patients using cannabis for Crohn's disease (CD) was ever published. To describe the effects of cannabis use in patients suffering from CD. In this retrospective observational study we examined disease activity, use of medication, need for surgery, and hospitalization before and after cannabis use in 30 patients (26 males) with CD. Disease activity was assessed by the Harvey Bradshaw index for Crohn's disease. Of the 30 patients 21 improved significantly after treatment with cannabis. The average Harvey Bradshaw index improved from 14 +/- 6.7 to 7 +/- 4.7 (P < 0.001). The need for other medication was significantly reduced. Fifteen of the patients had 19 surgeries during an average period of 9 years before cannabis use, but only 2 required surgery during an average period of 3 years of cannabis use. This is the first report of cannabis use in Crohn's disease in humans. The results indicate that cannabis may have a positive effect on disease activity, as reflected by reduction in disease activity index and in the need for other drugs and surgery. Prospective placebo-controlled studies are warranted to fully evaluate the efficacy and side effects of cannabis in CD.

  12. An Observational Study of Pulsations in Proto-Planetary Nebulae

    NASA Astrophysics Data System (ADS)

    Hrivnak, Bruce J.; Lu, Wenxian; Henson, Gary D.; Hillwig, Todd C.

    2016-01-01

    We have been carrying out a long-term monitoring program to study the light variability in proto-planetary nebulae (PPNe). PPNe are post-Asymptotic Giant Branch objects in transition between the AGB and PN phases in the evolution of low and intermediate-mass stars. As such, it is not surprising that they display pulsational variability. We have been carrying out photometric monitoring of 30 of these at the Valparaiso University campus observatory over the last 20 years, with the assistance of undergraduate students. The sample size has been enlarged over the past six years by observations made using telescopes in the SARA consortium at KPNO and CTIO. Periods have been determined for those of F-G spectral types. We have also enlarged the sample with PPNe from outside the Milky Way by determining periods of eight PPNe in the lower metalicity environment of the Magellanic Clouds. Periods for the entire sample range from 35 to 160 days. Some clear patterns have emerged, with those of higher temperature possessing shorter periods and smaller amplitudes, indicating a reduction in period and pulsation amplitude as the objects evolve. Radial velocity monitoring of several of the brightest of these has allowed us to document their changes in brightness, color, and size during a pulsation cycle. The results of this study will be presented. This research is supported by grants from the National Science Foundation (most recently AST 1413660), with additional student support from the Indiana Space Grant Consortium.

  13. Observational study of contracts processing at 29 CTSA sites.

    PubMed

    Kiriakis, James; Gaich, Nicholas; Johnston, S Claiborne; Kitterman, Darlene; Rosenblum, Daniel; Salberg, Libby; Rifkind, Adam

    2013-08-01

    We measured contracts final negotiation (FN) and full execution (FE) times using shared definitions in a prospective observational study of management of contracts for clinical trials at 29 CTSA institutions. Median FN and FE times were reached in 39 and 91 days, respectively; mean times for FN and FE were 55 and 103 days, respectively. Individual site medians ranged from 3 to 116 days for FN and 34 to 197 days for FE. The use of master agreements (MAs) and previously negotiated terms (PNTs) was associated with significant reduction of FN times by a mean of 33 days (p < 0) and 22 days (p < 0.001), respectively. PNTs, but not MAs, were associated with significantly reduced FE time (22 days, p < 0.007). Gap analysis revealed a gap of 22 days between contracts negotiation and Institutional Review Board (IRB) review and intervals of 33 days (contracts) and 48 days (IRB review) during which the process steps were being conducted alone, suggesting a potential benefit with parallel processing. These baseline data support a plan to investigate root causes of prolonged study start-up time by examining causes of variation and outliers. © 2013 Wiley Periodicals, Inc.

  14. Observational Study of Contracts Processing at 29 CTSA Sites

    PubMed Central

    Kiriakis, James; Gaich, Nicholas; Johnston, S. Claiborne; Kitterman, Darlene; Salberg, Libby; Rifkind, Adam

    2013-01-01

    Abstract We measured contracts final negotiation (FN) and full execution (FE) times using shared definitions in a prospective observational study of management of contracts for clinical trials at 29 CTSA institutions. Median FN and FE times were reached in 39 and 91 days, respectively; mean times for FN and FE were 55 and 103 days, respectively. Individual site medians ranged from 3 to 116 days for FN and 34 to 197 days for FE. The use of master agreements (MAs) and previously negotiated terms (PNTs) was associated with significant reduction of FN times by a mean of 33 days (p < 0) and 22 days (p < 0.001), respectively. PNTs, but not MAs, were associated with significantly reduced FE time (22 days, p < 0.007). Gap analysis revealed a gap of 22 days between contracts negotiation and Institutional Review Board (IRB) review and intervals of 33 days (contracts) and 48 days (IRB review) during which the process steps were being conducted alone, suggesting a potential benefit with parallel processing. These baseline data support a plan to investigate root causes of prolonged study start‐up time by examining causes of variation and outliers. PMID:23919362

  15. Safe medication management in specialized home healthcare - an observational study.

    PubMed

    Lindblad, Marléne; Flink, Maria; Ekstedt, Mirjam

    2017-08-24

    Medication management is a complex, error-prone process. The aim of this study was to explore what constitutes the complexity of the medication management process (MMP) in specialized home healthcare and how healthcare professionals handle this complexity. The study is theoretically based in resilience engineering. Data were collected during the MMP at three specialized home healthcare units in Sweden using two strategies: observation of workplaces and shadowing RNs in everyday work, including interviews. Transcribed material was analysed using grounded theory. The MMP in home healthcare was dynamic and complex with unclear boundaries of responsibilities, inadequate information systems and fluctuating work conditions. Healthcare professionals adapted their everyday clinical work by sharing responsibility and simultaneously being authoritative and preserving patients' active participation, autonomy and integrity. To promote a safe MMP, healthcare professionals constantly re-prioritized goals, handled gaps in communication and information transmission at a distance by creating new bridging solutions. Trade-offs and workarounds were necessary elements, but also posed a threat to patient safety, as these interim solutions were not systematically evaluated or devised learning strategies. To manage a safe medication process in home healthcare, healthcare professionals need to adapt to fluctuating conditions and create bridging strategies through multiple parallel activities distributed over time, space and actors. The healthcare professionals' strategies could be integrated in continuous learning, while preserving boundaries of safety, instead of being more or less interim solutions. Patients' and family caregivers' as active partners in the MMP may be an underestimated resource for a resilient home healthcare.

  16. Physical Activity in Public Parks of High and Low Socioeconomic Status in Colombia Using Observational Methods.

    PubMed

    Camargo, Diana Marina; Ramírez, Paula Camila; Quiroga, Vanesa; Ríos, Paola; Férmino, Rogério César; Sarmiento, Olga L

    2018-03-28

    Public parks are an important resource for the promotion of physical activity (PA). This is the first study in Colombia and the fourth in Latin America to describe the characteristics of park users and their levels of PA using objective measures. A systematic observation assessed sex, age, and the level of PA of users of 10 parks in an intermediate-size city in Colombia, classified in low (5 parks) and high (5 parks) socioeconomic status (SES). A total of 10 daily observations were conducted, in 5 days of the week during 3 periods: morning, afternoon, and evening. In total, 16,671 observations were completed, recording 46,047 users. A higher number of users per park, per day, were recorded in high SES (1195) versus low SES (647). More men were observed in low-SES than high-SES parks (70.1% vs 54.2%), as well as more children were observed in low-SES than high-SES parks (30.1% vs 15.9%). Older adults in high-SES parks were more frequent (9.5% vs 5.2%). Moderate to vigorous PA was higher in low-SES parks (71.7% vs 63.2%). Low-SES parks need more green spaces, walk/bike trails, and areas for PA. All parks need new programs to increase the number of users and their PA level, considering sex, age group, and period of the week.

  17. The assessment of cognitive errors using an observer-rated method.

    PubMed

    Drapeau, Martin

    2014-01-01

    Cognitive Errors (CEs) are a key construct in cognitive behavioral therapy (CBT). Integral to CBT is that individuals with depression process information in an overly negative or biased way, and that this bias is reflected in specific depressotypic CEs which are distinct from normal information processing. Despite the importance of this construct in CBT theory, practice, and research, few methods are available to researchers and clinicians to reliably identify CEs as they occur. In this paper, the author presents a rating system, the Cognitive Error Rating Scale, which can be used by trained observers to identify and assess the cognitive errors of patients or research participants in vivo, i.e., as they are used or reported by the patients or participants. The method is described, including some of the more important rating conventions to be considered when using the method. This paper also describes the 15 cognitive errors assessed, and the different summary scores, including valence of the CEs, that can be derived from the method.

  18. Studies on Training Ground Observers to Estimate Range to Aerial Targets.

    ERIC Educational Resources Information Center

    McCluskey, Michael R.; And Others

    Six pilot studies were conducted to determine the effects of training on range estimation performance for aerial targets, and to identify some of the relevant variables. Observers were trained to estimate ranges of 350, 400, 800, 1,500, or 2,500 meters. Several variations of range estimation training methods were used, including immediate…

  19. A Conceptual Study of Visual Training Methods.

    ERIC Educational Resources Information Center

    Aik, Chong-Tek

    2003-01-01

    Proposes a research study to investigate the effects of two visual training methods on the productivity of new workers on an assembly line at a wood products plant in Indonesia. Suggests that such a study would be useful to the managers in deciding what types of training would be most appropriate. (Contains 23 references.) (CAK)

  20. The Effect of DNA Extraction Methods on Observed Microbial Communities from Fibrous and Liquid Rumen Fractions of Dairy Cows.

    PubMed

    Vaidya, Jueeli D; van den Bogert, Bartholomeus; Edwards, Joan E; Boekhorst, Jos; van Gastelen, Sanne; Saccenti, Edoardo; Plugge, Caroline M; Smidt, Hauke

    2018-01-01

    DNA based methods have been widely used to study the complexity of the rumen microbiota, and it is well known that the method of DNA extraction is a critical step in enabling accurate assessment of this complexity. Rumen fluid (RF) and fibrous content (FC) fractions differ substantially in terms of their physical nature and associated microorganisms. The aim of this study was therefore to assess the effect of four DNA extraction methods (RBB, PBB, FDSS, PQIAmini) differing in cell lysis and/or DNA recovery methods on the observed microbial diversity in RF and FC fractions using samples from four rumen cannulated dairy cows fed 100% grass silage (GS100), 67% GS and 33% maize silage (GS67MS33), 33% GS and 67% MS (GS33MS67), or 100% MS (MS100). An ANOVA statistical test was applied on DNA quality and yield measurements, and it was found that the DNA yield was significantly affected by extraction method ( p < 0.001) and fraction ( p < 0.001). The 260/280 ratio was not affected by extraction ( p = 0.08) but was affected by fraction ( p = 0.03). On the other hand, the 260/230 ratio was affected by extraction method ( p < 0.001) but not affected by fraction ( p = 0.8). However, all four extraction procedures yielded DNA suitable for further analysis of bacterial, archaeal and anaerobic fungal communities using quantitative PCR and pyrosequencing of relevant taxonomic markers. Redundancy analysis (RDA) of bacterial 16S rRNA gene sequence data at the family level showed that there was a significant effect of rumen fraction ( p = 0.012), and that PBB ( p = 0.012) and FDSS ( p = 0.024) also significantly contributed to explaining the observed variation in bacterial community composition. Whilst the DNA extraction method affected the apparent bacterial community composition, no single extraction method could be concluded to be ineffective. No obvious effect of DNA extraction method on the anaerobic fungi or archaea was observed, although fraction effects were evident for both

  1. The Effect of DNA Extraction Methods on Observed Microbial Communities from Fibrous and Liquid Rumen Fractions of Dairy Cows

    PubMed Central

    Vaidya, Jueeli D.; van den Bogert, Bartholomeus; Edwards, Joan E.; Boekhorst, Jos; van Gastelen, Sanne; Saccenti, Edoardo; Plugge, Caroline M.; Smidt, Hauke

    2018-01-01

    DNA based methods have been widely used to study the complexity of the rumen microbiota, and it is well known that the method of DNA extraction is a critical step in enabling accurate assessment of this complexity. Rumen fluid (RF) and fibrous content (FC) fractions differ substantially in terms of their physical nature and associated microorganisms. The aim of this study was therefore to assess the effect of four DNA extraction methods (RBB, PBB, FDSS, PQIAmini) differing in cell lysis and/or DNA recovery methods on the observed microbial diversity in RF and FC fractions using samples from four rumen cannulated dairy cows fed 100% grass silage (GS100), 67% GS and 33% maize silage (GS67MS33), 33% GS and 67% MS (GS33MS67), or 100% MS (MS100). An ANOVA statistical test was applied on DNA quality and yield measurements, and it was found that the DNA yield was significantly affected by extraction method (p < 0.001) and fraction (p < 0.001). The 260/280 ratio was not affected by extraction (p = 0.08) but was affected by fraction (p = 0.03). On the other hand, the 260/230 ratio was affected by extraction method (p < 0.001) but not affected by fraction (p = 0.8). However, all four extraction procedures yielded DNA suitable for further analysis of bacterial, archaeal and anaerobic fungal communities using quantitative PCR and pyrosequencing of relevant taxonomic markers. Redundancy analysis (RDA) of bacterial 16S rRNA gene sequence data at the family level showed that there was a significant effect of rumen fraction (p = 0.012), and that PBB (p = 0.012) and FDSS (p = 0.024) also significantly contributed to explaining the observed variation in bacterial community composition. Whilst the DNA extraction method affected the apparent bacterial community composition, no single extraction method could be concluded to be ineffective. No obvious effect of DNA extraction method on the anaerobic fungi or archaea was observed, although fraction effects were evident for both. In

  2. Validity of an Observation Method for Assessing Pain Behavior in Individuals With Multiple Sclerosis

    PubMed Central

    Cook, Karon F.; Roddey, Toni S.; Bamer, Alyssa M.; Amtmann, Dagmar; Keefe, Francis J

    2012-01-01

    Context Pain is a common and complex experience for individuals who live with multiple sclerosis (MS) that interferes with physical, psychological and social function. A valid and reliable tool for quantifying observed pain behaviors in MS is critical to understanding how pain behaviors contribute to pain-related disability in this clinical population. Objectives To evaluate the reliability and validity of a pain behavioral observation protocol in individuals who have MS. Methods Community-dwelling volunteers with multiple sclerosis (N=30), back pain (N=5), or arthritis (N=8) were recruited based on clinician referrals, advertisements, fliers, web postings, and participation in previous research. Participants completed measures of pain severity, pain interference, and self-reported pain behaviors and were videotaped doing typical activities (e.g., walking, sitting). Two coders independently recorded frequencies of pain behaviors by category (e.g., guarding, bracing) and inter-rater reliability statistics were calculated. Naïve observers reviewed videotapes of individuals with MS and rated their pain. Spearman correlations were calculated between pain behavior frequencies and self-reported pain and pain ratings by naïve observers. Results Inter-rater reliability estimates indicated the reliability of pain codes in the MS sample. Kappa coefficients ranged from moderate agreement (sighing = 0.40) to substantial agreement (guarding = 0.83). These values were comparable to those obtained in the combined back pain and arthritis sample. Concurrent validity was supported by correlations with self-reported pain (0.46-0.53) and with self-reports of pain behaviors (0.58). Construct validity was supported by finding of 0.87 correlation between total pain behaviors observed by coders and mean pain ratings by naïve observers. Conclusion Results support use of the pain behavior observation protocol for assessing pain behaviors of individuals with MS. Valid assessments of pain

  3. Digital holographic tomography method for 3D observation of domain patterns in ferroelectric single crystals

    NASA Astrophysics Data System (ADS)

    Mokrý, Pavel; Psota, Pavel; Steiger, Kateřina; Václavík, Jan; Vápenka, David; Doleček, Roman; Vojtíšek, Petr; Sládek, Juraj; Lédl, Vít.

    2016-11-01

    We report on the development and implementation of the digital holographic tomography for the three-dimensio- nal (3D) observations of the domain patterns in the ferroelectric single crystals. Ferroelectric materials represent a group of materials, whose macroscopic dielectric, electromechanical, and elastic properties are greatly in uenced by the presence of domain patterns. Understanding the role of domain patterns on the aforementioned properties require the experimental techniques, which allow the precise 3D measurements of the spatial distribution of ferroelectric domains in the single crystal. Unfortunately, such techniques are rather limited at this time. The most frequently used piezoelectric atomic force microscopy allows 2D observations on the ferroelectric sample surface. Optical methods based on the birefringence measurements provide parameters of the domain patterns averaged over the sample volume. In this paper, we analyze the possibility that the spatial distribution of the ferroelectric domains can be obtained by means of the measurement of the wavefront deformation of the transmitted optical wave. We demonstrate that the spatial distribution of the ferroelectric domains can be determined by means of the measurement of the spatial distribution of the refractive index. Finally, it is demonstrated that the measurements of wavefront deformations generated in ferroelectric polydomain systems with small variations of the refractive index provide data, which can be further processed by means of the conventional tomographic methods.

  4. [Perception of glaucoma and therapeutic adherence: A multicenter observational study].

    PubMed

    Chiche, A; Martin, G; Brasnu de Cenival, E; Rousseau, A; Giocanti, A; Fel, A; Kallel, S; Lombardi, M; Hamard, P; Baudouin, C; Labbe, A

    2017-06-01

    The purpose of this study was to evaluate medication adherence of glaucoma patients through the "Glaucoma treatment compliance assessment tool (GTCAT)" questionnaire and to correlate the results with clinical parameters. This multicenter prospective observational study was performed in the Département hospitalo-universitaire (DHU) Sight Restore, Paris, France. All patients had been followed for chronic open angle glaucoma (COAG) for at least 3 years. A French version of the GTCAT questionnaire was administered to patients. The results were correlated with clinical parameters of glaucoma, such as duration of disease, medications used, intraocular pressure (IOP) and mean deviation (MD) of the most recent visual field. Seventy-three patients were included in our study, with 60.9% declaring that they fully adhered to the treatment. There was a correlation between the amount of days missing treatment and difficulties using the eye drops. The main cause of missing the drops was forgetfulness (75%), followed by unavailability of the drop when it was time to take it (37.5%). The impact of glaucoma on quality of life was correlated to the amount of adverse effects of topical medications. The patient's perception of the importance of preserving vision was correlated to the level of confidence in the physician concerning the diagnosis of glaucoma. In glaucoma patients, the use of the GTCAT questionnaire confirmed the complex relationship between the patient, the disease and its treatment, and even his or her relationship with the ophthalmologist. These results emphasized the importance of therapeutic education but also the negative role of side effects of the eye drops on treatment adherence in glaucoma patients. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  5. Exploring interprofessional, interagency multimorbidity care: case study based observational research

    PubMed Central

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

    2017-01-01

    Background The increase in multimorbidity or co-occurring chronic illnesses is a leading healthcare concern. Patients with multimorbidity require ongoing care from many different professionals and agencies, and often report a lack of integrated care. Objective To explore the daily help-seeking behaviours of patients with multimorbidity, including which health professionals they seek help from, how professionals work together, and perceptions and characteristics of effective interprofessional, interagency multimorbidity care. Design Using a case study observational research design, multiple data sources were assembled for four patients with multimorbidity, identified by two general practitioners in New Zealand. In this paper, two case studies are presented, including the recorded instances of contact and communication between patients and professionals, and between professionals. Professional interactions were categorized as consultation, coordination, or collaboration. Results The two case studies illustrated two female patients with likely similar educational levels, but with different profiles of multimorbidity, social circumstances, and personal capabilities, involving various professionals and agencies. Engagement between professionals showed varying levels of interaction and a lack of clarity about leadership or care coordination. The majority of interactions were one-to-one consultations and rarely involved coordination and collaboration. Patients were rarely included in communications between professionals. Conclusion Cases constructed from multiple data sources illustrate the complexity of day-to-day, interprofessional, interagency multimorbidity care. While consultation is the most frequent mode of professional interaction, targeted coordinated and collaborative interactions (including the patient) are highly effective activities. Greater attention should be given to developing and facilitating these interactions and determining who should lead them. PMID

  6. Methods for the Study of Gonadal Development.

    PubMed

    Piprek, Rafal P

    2016-01-01

    Current knowledge on gonadal development and sex determination is the product of many decades of research involving a variety of scientific methods from different biological disciplines such as histology, genetics, biochemistry, and molecular biology. The earliest embryological investigations, followed by the invention of microscopy and staining methods, were based on histological examinations. The most robust development of histological staining techniques occurred in the second half of the nineteenth century and resulted in structural descriptions of gonadogenesis. These first studies on gonadal development were conducted on domesticated animals; however, currently the mouse is the most extensively studied species. The next key point in the study of gonadogenesis was the advancement of methods allowing for the in vitro culture of fetal gonads. For instance, this led to the description of the origin of cell lines forming the gonads. Protein detection using antibodies and immunolabeling methods and the use of reporter genes were also invaluable for developmental studies, enabling the visualization of the formation of gonadal structure. Recently, genetic and molecular biology techniques, especially gene expression analysis, have revolutionized studies on gonadogenesis and have provided insight into the molecular mechanisms that govern this process. The successive invention of new methods is reflected in the progress of research on gonadal development.

  7. SS-HORSE method for studying resonances

    SciTech Connect

    Blokhintsev, L. D.; Mazur, A. I.; Mazur, I. A., E-mail: 008043@pnu.edu.ru

    A new method for analyzing resonance states based on the Harmonic-Oscillator Representation of Scattering Equations (HORSE) formalism and analytic properties of partial-wave scattering amplitudes is proposed. The method is tested by applying it to the model problem of neutral-particle scattering and can be used to study resonance states on the basis of microscopic calculations performed within various versions of the shell model.

  8. An Unroofing Method to Observe the Cytoskeleton Directly at Molecular Resolution Using Atomic Force Microscopy

    PubMed Central

    Usukura, Eiji; Narita, Akihiro; Yagi, Akira; Ito, Shuichi; Usukura, Jiro

    2016-01-01

    An improved unroofing method enabled the cantilever of an atomic force microscope (AFM) to reach directly into a cell to visualize the intracellular cytoskeletal actin filaments, microtubules, clathrin coats, and caveolae in phosphate-buffered saline (PBS) at a higher resolution than conventional electron microscopy. All of the actin filaments clearly exhibited a short periodicity of approximately 5–6 nm, which was derived from globular actins linked to each other to form filaments, as well as a long helical periodicity. The polarity of the actin filaments appeared to be determined by the shape of the periodic striations. Microtubules were identified based on their thickness. Clathrin coats and caveolae were observed on the cytoplasmic surface of cell membranes. The area containing clathrin molecules and their terminal domains was directly visualized. Characteristic ridge structures located at the surface of the caveolae were observed at high resolution, similar to those observed with electron microscopy (EM). Overall, unroofing allowed intracellular AFM imaging in a liquid environment with a level of quality equivalent or superior to that of EM. Thus, AFMs are anticipated to provide cutting-edge findings in cell biology and histology. PMID:27273367

  9. Quantitative Assessment of Blood Pressure Measurement Accuracy and Variability from Visual Auscultation Method by Observers without Receiving Medical Training

    PubMed Central

    Feng, Yong; Chen, Aiqing

    2017-01-01

    This study aimed to quantify blood pressure (BP) measurement accuracy and variability with different techniques. Thirty video clips of BP recordings from the BHS training database were converted to Korotkoff sound waveforms. Ten observers without receiving medical training were asked to determine BPs using (a) traditional manual auscultatory method and (b) visual auscultation method by visualizing the Korotkoff sound waveform, which was repeated three times on different days. The measurement error was calculated against the reference answers, and the measurement variability was calculated from the SD of the three repeats. Statistical analysis showed that, in comparison with the auscultatory method, visual method significantly reduced overall variability from 2.2 to 1.1 mmHg for SBP and from 1.9 to 0.9 mmHg for DBP (both p < 0.001). It also showed that BP measurement errors were significant for both techniques (all p < 0.01, except DBP from the traditional method). Although significant, the overall mean errors were small (−1.5 and −1.2 mmHg for SBP and −0.7 and 2.6 mmHg for DBP, resp., from the traditional auscultatory and visual auscultation methods). In conclusion, the visual auscultation method had the ability to achieve an acceptable degree of BP measurement accuracy, with smaller variability in comparison with the traditional auscultatory method. PMID:29423405

  10. Physician spending and subsequent risk of malpractice claims: observational study

    PubMed Central

    Schoemaker, Lena; Bhattacharya, Jay; Seabury, Seth A

    2015-01-01

    Study question Is a higher use of resources by physicians associated with a reduced risk of malpractice claims? Methods Using data on nearly all admissions to acute care hospitals in Florida during 2000-09 linked to malpractice history of the attending physician, this study investigated whether physicians in seven specialties with higher average hospital charges in a year were less likely to face an allegation of malpractice in the following year, adjusting for patient characteristics, comorbidities, and diagnosis. To provide clinical context, the study focused on obstetrics, where the choice of caesarean deliveries are suggested to be influenced by defensive medicine, and whether obstetricians with higher adjusted caesarean rates in a year had fewer alleged malpractice incidents the following year. Study answer and limitations The data included 24 637 physicians, 154 725 physician years, and 18 352 391 hospital admissions; 4342 malpractice claims were made against physicians (2.8% per physician year). Across specialties, greater average spending by physicians was associated with reduced risk of incurring a malpractice claim. For example, among internists, the probability of experiencing an alleged malpractice incident in the following year ranged from 1.5% (95% confidence interval 1.2% to 1.7%) in the bottom spending fifth ($19 725 (£12 800; €17 400) per hospital admission) to 0.3% (0.2% to 0.5%) in the top fifth ($39 379 per hospital admission). In six of the specialties, a greater use of resources was associated with statistically significantly lower subsequent rates of alleged malpractice incidents. A principal limitation of this study is that information on illness severity was lacking. It is also uncertain whether higher spending is defensively motivated. What this study adds Within specialty and after adjustment for patient characteristics, higher resource use by physicians is associated with fewer malpractice claims. Funding, competing

  11. TEACH: An Ethogram-Based Method to Observe and Record Teaching Behavior

    ERIC Educational Resources Information Center

    Kline, Michelle Ann

    2017-01-01

    Teaching has attracted growing research attention in studies of human and animal behavior as a crucial behavior that coevolved with human cultural capacities. However, the synthesis of data on teaching across species and across human populations has proven elusive because researchers use a variety of definitions and methods to approach the topic.…

  12. A Study on Feature of Eye Tracking in Difference of Skill Level during Observational Learning of Movement

    NASA Astrophysics Data System (ADS)

    Nuruki, Atsuo; Shimozono, Tomoyuki; Kawabata, Takuro; Yamada, Masafumi; Yunokuchi, Kazutomo; Maruyama, Atsuo

    Recently, it often said that it is one of the means that the observational learning promotes the acquisition of sports and athletic skills. We think that the inexperienced person can efficiently acquire athletic skills by using the observational method of the expert as an index of the observational method in the observational learning. Then, in the present study, the expert and inexperienced person's glance characteristic were compared, and it was examined whether the observational method of the expert was able to be used as an index of the observational method of the inexperienced person. The glance characteristics are a glance transition, glance total moved distance, the gazing duration, moreover glance moved distance and radial velocity between each gaze points. Additionally, we investigated whether there was a change in physical performance before and after the observational learning, and two different observational learning groups (the expert's observational method group, the free observation group). In result, it was clarified that the expert concentrated, observed a constant part of the movement, and the inexperienced person was observing the entire movement. Moreover, the result that glance total moved distance was shorter than the inexperienced person, and expert's gazing duration was longer than the inexperienced person. It was clarified that the expert was efficiently emphatically observing the point of the movement from these results. In addition, the inexperienced persons have advanced physical performance through the observational learning. Then the expert's observational method group advanced physical performance better than the free observation group. Therefore we suggested that the observational method of the expert be able to be used as an index of the method of observing the inexperienced person.

  13. Breast feeding and the weekend effect: an observational study

    PubMed Central

    Fitzsimons, Emla; Vera-Hernández, Marcos

    2016-01-01

    Objective To compare the incidence of breast feeding by day of week of birth. Design Retrospective database study using 16 508 records from the 2005 and 2010 Infant Feeding Surveys. Setting England and Wales, UK. Participants Mothers of a sample of births from among all registered births in the periods August–September 2005 and August–October 2010. Main outcome measure Incidence of breast feeding after birth. Results Among babies of mothers who left full-time education aged 16 or under, the incidence of breast feeding was 6.7 percentage points lower (95% CI 1.4 to 12.1 percentage points) for those born on Saturdays than for those born on Mondays–Thursdays. No such differences by day of week of birth were observed among babies of mothers who left school aged 17 or over. Conclusions Breastfeeding policy should take into account differences in breast feeding by day of week of birth, which are apparent among low-educated mothers. Further research is needed to ascertain the reason for this finding. PMID:27401354

  14. Breast feeding and the weekend effect: an observational study.

    PubMed

    Fitzsimons, Emla; Vera-Hernández, Marcos

    2016-07-08

    To compare the incidence of breast feeding by day of week of birth. Retrospective database study using 16 508 records from the 2005 and 2010 Infant Feeding Surveys. England and Wales, UK. Mothers of a sample of births from among all registered births in the periods August-September 2005 and August-October 2010. Incidence of breast feeding after birth. Among babies of mothers who left full-time education aged 16 or under, the incidence of breast feeding was 6.7 percentage points lower (95% CI 1.4 to 12.1 percentage points) for those born on Saturdays than for those born on Mondays-Thursdays. No such differences by day of week of birth were observed among babies of mothers who left school aged 17 or over. Breastfeeding policy should take into account differences in breast feeding by day of week of birth, which are apparent among low-educated mothers. Further research is needed to ascertain the reason for this finding. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  15. Observed wave characteristics during growth and decay: a case study

    NASA Astrophysics Data System (ADS)

    Prasada Rao, C. V. K.; Baba, M.

    1996-10-01

    Observed 1-h time series data on sea surface waves in the shelf waters off Goa, west coast of India (depth 80 m), during 17-24 March 1986, are analyzed with reference to the prevailing synoptic winds to understand wave growth and decay aspects. Wind speeds ( U10) ranged from 0 to 11.5 m s -1, whereas significant wave height ( Hs) varied between 0.6 and 2.3 m. Cross-correlation analysis between U10 and Hs revealed a time-lag of 4 h. A relationship is obtained between wave steepness ( H s/L ) and wave age ( C/U10) viz. Log 10( H s/L = -0.53 Log 10( C/U 10) - 1.385. Phillips' hypothesis of f-5 formula for equilibrium range of wave spectrum and relationship between non-dimensional energy ( E * = Eg 2/U *4) and non-dimensional peak frequency ( v * = U *f m/g ) are studied. Correlation of non-dimensional wave parameters ( E * and v *) using the present data showed a better aereement with Hasselmann et al. (1976) when comnared to Toba (1978).

  16. DNA Fingerprinting Validates Seed Dispersal Curves from Observational Studies in the Neotropical Legume Parkia

    PubMed Central

    Heymann, Eckhard W.; Lüttmann, Kathrin; Michalczyk, Inga M.; Saboya, Pedro Pablo Pinedo; Ziegenhagen, Birgit; Bialozyt, Ronald

    2012-01-01

    Background Determining the distances over which seeds are dispersed is a crucial component for examining spatial patterns of seed dispersal and their consequences for plant reproductive success and population structure. However, following the fate of individual seeds after removal from the source tree till deposition at a distant place is generally extremely difficult. Here we provide a comparison of observationally and genetically determined seed dispersal distances and dispersal curves in a Neotropical animal-plant system. Methodology/Principal Findings In a field study on the dispersal of seeds of three Parkia (Fabaceae) species by two Neotropical primate species, Saguinus fuscicollis and Saguinus mystax, in Peruvian Amazonia, we observationally determined dispersal distances. These dispersal distances were then validated through DNA fingerprinting, by matching DNA from the maternally derived seed coat to DNA from potential source trees. We found that dispersal distances are strongly right-skewed, and that distributions obtained through observational and genetic methods and fitted distributions do not differ significantly from each other. Conclusions/Significance Our study showed that seed dispersal distances can be reliably estimated through observational methods when a strict criterion for inclusion of seeds is observed. Furthermore, dispersal distances produced by the two primate species indicated that these primates fulfil one of the criteria for efficient seed dispersers. Finally, our study demonstrated that DNA extraction methods so far employed for temperate plant species can be successfully used for hard-seeded tropical plants. PMID:22514748

  17. A concealed observational study of infection control and safe injection practices in Jordanian governmental hospitals.

    PubMed

    Al-Rawajfah, Omar M; Tubaishat, Ahmad

    2017-10-01

    The recognized international organizations on infection prevention recommend using an observational method as the gold standard procedure for assessing health care professional's compliance with standard infection control practices. However, observational studies are rarely used in Jordanian infection control studies. This study aimed to evaluate injection practices among nurses working in Jordanian governmental hospitals. A cross-sectional concealed observational design is used for this study. A convenience sampling technique was used to recruit a sample of nurses working in governmental hospitals in Jordan. Participants were unaware of the time and observer during the observation episode. A total of 384 nurses from 9 different hospitals participated in the study. A total of 835 injections events were observed, of which 73.9% were performed without handwashing, 64.5% without gloving, and 27.5% were followed by needle recapping. Handwashing rate was the lowest (18.9%) when injections were performed by beginner nurses. Subcutaneous injections were associated with the lowest rate (26.7%) of postinjection handwashing compared with other routes. This study demonstrates the need for focused and effective infection control educational programs in Jordanian hospitals. Future studies should consider exploring the whole infection control practices related to waste disposal and the roles of the infection control nurse in this process in Jordanian hospitals. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  18. Travel-related morbidity in children: a prospective observational study.

    PubMed

    van Rijn, Suzanne F; Driessen, Gertjan; Overbosch, David; van Genderen, Perry J J

    2012-01-01

    Scarce data are available on the occurrence of ailments and diseases in children during travel. We studied the characteristics and frequencies of ailments in children aged 0 to 18 years and their parents during traveling. A prospective observational study on ailments reported by children and parents traveling to (sub)tropical countries was conducted. The ailments were semi-quantitatively graded as mild, moderate, or severe; ailments were expressed as ailment rates per personmonth of travel. A total of 152 children and 47 parents kept track of their ailments for a total of 497 and 154 weeks, respectively. The children reported a mean ailment rate of 7.0 (5.6-8.4) ailments per personmonth of travel; 17.4% of the ailments were graded as moderate and 1.4% as severe. The parents reported a mean ailment rate of 4.4 (3.1-5.7); 10.8% of the ailments were graded as moderate and 5.5% as severe. Skin problems like insect bites, sunburn and itch, and abdominal complaints like diarrhea were frequently reported ailments in both children and parents. Children in the age category 12 to 18 years showed a significantly higher ailment rate of 11.2 (6.8-14.1) than their parents. Skin problems and abdominal problems like diarrhea are frequently reported ailments in children and their parents and show a high tendency to recur during travel. The majority of these ailments are mild but occasionally interfere with planned activities. Children in the age group 12 to 18 years are at a greater risk of developing ailments during a stay in a (sub)tropical country and they should be actively informed about the health risks of traveling to the tropics. © 2011 International Society of Travel Medicine.

  19. The G-spot: an observational MRI pilot study.

    PubMed

    Maratos, Y K; Gombergh, R; Cornier, E; Minart, J P; Amoretti, N; Mpotsaris, A

    2016-08-01

    To identify a G-spot complex (GSC) in vivo in MRI examinations at 1.5 Tesla field strength. Observational study. Single centre. Twenty-one consecutive patients (January-March 2014). Imaging analysis of routine imaging protocols for usual medical indications with and without concomitant opacification of the vaginal cavity with inert ultrasound gel. The gel distends the otherwise collapsed vaginal walls, allowing for an improved discrimination of anatomic features. The macroscopic and histological results recently derived from the dissections of fresh cadavers by Ostrzenski et al. were translated into imaging characteristics to be expected in the respective MRI sequences (e.g. T1- and T2-weighted) in search of an in vivo correlate of the GSC. Age, menopause status, medical indication and diagnosis were co-variables. To analyse primarily whether MRI imaging is able to depict a distinct morphological entity in vivo matching the GSC, based on anatomical descriptions published recently. The elaboration of an appropriate MRI-imaging protocol was a secondary aim. A total of 21 studies were obtained. A GSC was identified within the anterior vaginal wall in 13/21 patients (62%). In all, 10/21 (48%) had vaginal gel opacification. We identified a GSC in 10/10 patients (100%) with opacification in all three planes of the T2 images. This was only true for 3/11 cases (27%) without opacification. There is evidence for an in vivo morphological correlate to the postmortem anatomical findings of a GSC described by Ostrzenski et al.; its visibility in MRI imaging can be significantly improved with vaginal opacification by ultrasound gel. Identification of G-spot by MRI with vaginal gel-opacification in 13/21 patients. © 2016 Royal College of Obstetricians and Gynaecologists.

  20. Survival after postoperative morbidity: a longitudinal observational cohort study.

    PubMed

    Moonesinghe, S R; Harris, S; Mythen, M G; Rowan, K M; Haddad, F S; Emberton, M; Grocott, M P W

    2014-12-01

    Previous studies have suggested that there may be long-term harm associated with postoperative complications. Uncertainty exists however, because of the need for risk adjustment and inconsistent definitions of postoperative morbidity. We did a longitudinal observational cohort study of patients undergoing major surgery. Case-mix adjustment was applied and morbidity was recorded using a validated outcome measure. Cox proportional hazards modelling using time-dependent covariates was used to measure the independent relationship between prolonged postoperative morbidity and longer term survival. Data were analysed for 1362 patients. The median length of stay was 9 days and the median follow-up time was 6.5 yr. Independent of perioperative risk, postoperative neurological morbidity (prevalence 2.9%) was associated with a relative hazard for long-term mortality of 2.00 [P=0.001; 95% confidence interval (CI) 1.32-3.04]. Prolonged postoperative morbidity (prevalence 15.6%) conferred a relative hazard for death in the first 12 months after surgery of 3.51 (P<0.001; 95% CI 2.28-5.42) and for the next 2 yr of 2.44 (P<0.001; 95% CI 1.62-3.65), returning to baseline thereafter. Prolonged morbidity after surgery is associated with a risk of premature death for a longer duration than perhaps is commonly thought; however, this risk falls with time. We suggest that prolonged postoperative morbidity measured in this way may be a valid indicator of the quality of surgical healthcare. Our findings reinforce the importance of research and quality improvement initiatives aimed at reducing the duration and severity of postoperative complications. © The Author 2014. Published by Oxford University Press on behalf of the British Journal of Anaesthesia.

  1. Early Postoperative Perils of Intraventricular Tumors: An Observational Comparative Study.

    PubMed

    Schär, Ralph T; Schwarz, Christa; Söll, Nicole; Raabe, Andreas; Z'Graggen, Werner J; Beck, Jürgen

    2018-05-01

    Early postoperative patient surveillance after removal of intraventricular tumors is often hindered by delayed awakening and prolonged somnolence. The objective of this study was to analyze the incidence of early critical postoperative events after elective craniotomy for intraventricular tumors in adults compared with extraventricular lesions. An observational comparative study was conducted on adult patients who had undergone first-time elective craniotomy between November 2011 and August 2016. Patients were stratified into extraventricular lesions (group 1) and intraventricular tumors (group 2). The rates of late extubation, early postoperative seizures, emergency head computed tomography (CT) scans, and urgent surgical intervention within 48 hours and mortality within 30 days of surgery were analyzed from a prospective database. A total of 977 elective craniotomies were analyzed, including 951 (97.3%) in group 1 and 26 (2.7%) in group 2. Emergency CT scans were ordered significantly more frequently in group 2 (34.6% vs. 8.4%; odds ratio, 5.76; 95% confidence interval [CI], 2.49-13.35; P = 0.0002), and the incidence of urgent surgical intervention was significantly higher in group 2 (11.5% vs. 0.8%; odds ratio, 15.38; 95% CI, 3.83-61.72; P = 0.002). The main reason for urgent surgical intervention in group 2 was acute obstructive hydrocephalus. Overall surgical mortality after 30 days was 0.3% (3 cases in group 1, no cases in group 2). Intraventricular tumors are at significantly higher risk for early emergency head CT and urgent surgical intervention. This patient cohort might benefit from routine intraoperative and early postoperative imaging, as well as intraoperative extraventricular drain placement. Copyright © 2018 Elsevier Inc. All rights reserved.

  2. [The aggression in SPDC: an observational study. Preliminary data].

    PubMed

    Minutolo, Giuseppe; Cannavò, Dario; Petralia, Antonino; Gandolfo, Liliana; Palermo, Filippo; Aguglia, Eugenio

    2010-01-01

    In the different psychiatric disorders the aggression often leads to uncontrolled events, taking aspects of impulsiveness and irrationality. Our research proposes the assessment of socio-demographic and clinical characteristics of patients with a psychiatric disorder, who presented an aggressive event. The observational study was conducted on a sample of 50 patients (34 men and 16 women), hospitalized following the manifestation of an aggressive event. For each patient was provided an assessment of socio-demographic and clinical variables and a psychometric investigation through: the OAS, for the analysis of aggressive episodes; the BDHI, for the hostile behavior and attitudes; the BIS-11, for the impulsiveness and the BPRS for the psychopathological aspects. Among the socio-demographic features investigated, the highest correlation with aggressive behavior was related to the concomitant substance abuse, type of admission to psychiatric hospital and the male gender. The OAS has shown a greater propensity to directed-aggression in males with schizophrenia, and self-directed in females with major depression. The BPRS has shown a positive correlation between hetero-directed aggressive behavior and positive symptomatology, and between the self-directed and depression, risk of suicide, feelings of guilt and somatic concerns. The BDHI has indicated greater suspicion in women's group. The hypothesis that aggression is otherwise related to specific socio-demographic and clinical characteristics was confirmed by our study. The data suggest that early identification and assessment of potential risk factors involved in the genesis of aggressive episodes would allow the clinician to implement a better strategy for prevention and intervention.

  3. Renal Replacement Therapy in Severe Burns: A Multicenter Observational Study.

    PubMed

    Chung, Kevin K; Coates, Elsa C; Hickerson, William L; Arnold-Ross, Angela L; Caruso, Daniel M; Albrecht, Marlene; Arnoldo, Brett D; Howard, Christina; Johnson, Laura S; McLawhorn, Melissa M; Friedman, Bruce; Sprague, Amy M; Mosier, Michael J; Conrad, Peggie F; Smith, David J; Karlnoski, Rachel A; Aden, James K; Mann-Salinas, Elizabeth A; Wolf, Steven E

    2018-06-20

    Acute kidney injury (AKI) after severe burns is historically associated with a high mortality. Over the past two decades, various modes of renal replacement therapy (RRT) have been utilized in this population. The purpose of this multicenter study was to evaluate demographic, treatment and outcomes data among severe burn patients treated with RRT collectively at various burn centers around the United States. After institutional review board approval, a multicenter observational study was conducted. All adult patients 18 or older, admitted with severe burns who were placed on RRT for acute indications but not randomized into a concurrently enrolling interventional trial were included. Across 8 participating burn centers, 171 subjects were enrolled during a 4 year period. Complete data was available in 170 subjects with a mean age of 51±17, percent total body surface area (TBSA) burn of 38±26% and Injury Severity Score of 27±21. 80% of subjects were male and 34% were diagnosed with smoke inhalation injury. The preferred mode of therapy was continuous venovenous hemofiltration at a mean delivered dose of 37±19 (mL/kg/hr) and a treatment duration of 13±24 days. Overall, in hospital mortality was 50%. Among survivors, 21% required RRT upon discharge from the hospital while 9% continued to require RRT 6 months after discharge. This is the first multi-center cohort of burn patients who underwent RRT reported to date. Overall mortality is comparable to other critically ill populations who undergo RRT. Most patients who survive to discharge eventually recover renal function.

  4. Endotoxin Elimination in Patients with Septic Shock: An Observation Study.

    PubMed

    Adamik, Barbara; Zielinski, Stanislaw; Smiechowicz, Jakub; Kübler, Andrzej

    2015-12-01

    To evaluate the effectiveness of endotoxin elimination with an adsorption column in patients with septic shock and endotoxemia. The elimination therapy was guided by a new bedside method of measuring endotoxin activity (EA). Intensive care unit (ICU) patients with septic shock and suspected Gram-negative infection were consecutively added to the study group within the first 24 h. Endotoxin elimination was performed using hemoperfusion with the Alteco LPS Adsorber. The primary endpoint was improvement in organ function within the first 24 h of treatment. A secondary objective was to assess the usefulness of a new method of measuring EA to help guide endotoxin elimination therapy. Out of 64 patients 18 had a high baseline EA [0.70 EA units (0.66-0.77)]. Those patients had endotoxin elimination treatment in addition to conventional medical therapy. At 24 h after endotoxin elimination, the EA had decreased to 0.56 EA units (0.43-0.77), (p = 0.005); MAP increased from 69 (62-80) to 80 mm Hg (68-88), (p = 0.002), and noradrenaline use decreased from 0.28 (0.15-0.80) to 0.1 μg/kg/min (0.00-0.70) at the same time (p = 0.04). The SOFA score had decreased from 11 (9-15) to 9 (7-14) points 24 h after endotoxin elimination (p = 0.01) with a median delta SOFA -2 points. Endotoxin elimination did not have a significant effect on the ICU length of stay or ICU mortality. Effective endotoxin elimination resulted in a significant improvement in hemodynamic parameters and of organ function. The application of the EA assay was useful for the bedside monitoring of endotoxemia in critically ill ICU patients.

  5. Applying Agile Methods to the Development of a Community-Based Sea Ice Observations Database

    NASA Astrophysics Data System (ADS)

    Pulsifer, P. L.; Collins, J. A.; Kaufman, M.; Eicken, H.; Parsons, M. A.; Gearheard, S.

    2011-12-01

    Local and traditional knowledge and community-based monitoring programs are increasingly being recognized as an important part of establishing an Arctic observing network, and understanding Arctic environmental change. The Seasonal Ice Zone Observing Network (SIZONet, http://www.sizonet.org) project has implemented an integrated program for observing seasonal ice in Alaska. Observation and analysis by local sea ice experts helps track seasonal and inter-annual variability of the ice cover and its use by coastal communities. The ELOKA project (http://eloka-arctic.org) is collaborating with SIZONet on the development of a community accessible, Web-based application for collecting and distributing local observations. The SIZONet project is dealing with complicated qualitative and quantitative data collected from a growing number of observers in different communities while concurrently working to design a system that will serve a wide range of different end users including Arctic residents, scientists, educators, and other stakeholders with a need for sea ice information. The benefits of linking and integrating knowledge from communities and university-based researchers are clear, however, development of an information system in this multidisciplinary, multi-participant context is challenging. Participants are geographically distributed, have different levels of technical expertise, and have varying goals for how the system will be used. As previously reported (Pulsifer et al. 2010), new technologies have been used to deal with some of the challenges presented in this complex development context. In this paper, we report on the challenges and innovations related to working as a multi-disciplinary software development team. Specifically, we discuss how Agile software development methods have been used in defining and refining user needs, developing prototypes, and releasing a production level application. We provide an overview of the production application that

  6. 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

  7. Observational and numerical studies of extreme frontal scale contraction

    NASA Technical Reports Server (NTRS)

    Koch, Steven E.

    1995-01-01

    The general objective of this effort is to increase understanding of how frontal scale contraction processes may create and sustain intense mesoscale precipitation along intensifying cold fronts. The five-part project (an expansion of the originally proposed two-part project) employed conventional meteorological data, special mesoscale data, remote sensing measurements, and various numerical models. First an idealized hydrostatic modeling study of the scale contraction effects of differential cloud cover on low-level frontal structure and dynamics was completed and published in a peer-reviewed journal. The second objective was to complete and publish the results from a three dimensional numerical model simulation of a cold front in which differential sensible heating related to cloud coverage patterns was apparently crucial in the formation of a severe frontal squall line. The third objective was to use a nonhydrostatic model to examine the nonlinear interactions between the transverse circulation arising from inhomogeneous cloud cover, the adiabatic frontal circulation related to semi-geostrophic forcing, and diabatic effects related to precipitation processes, in the development of a density current-like microstructure at the leading edge of cold fronts. Although the development of a frontal model that could be used to initialize such a primitive equation model was begun, we decided to focus our efforts instead on a project that could be successfully completed in this short time, due to the lack of prospects for continued NASA funding beyond this first year (our proposal was not accepted for future funding). Thus, a fourth task was added, which was to use the nonhydrostatic model to test tentative hypotheses developed from the most detailed observations ever obtained on a density current (primarily sodar and wind profiler data). These simulations were successfully completed, the findings were reported at a scientific conference, and the results have recently been

  8. Development and reliability of an observation method to assess food intake of young children in child care.

    PubMed

    Ball, Sarah C; Benjamin, Sara E; Ward, Dianne S

    2007-04-01

    To our knowledge, a direct observation protocol for assessing dietary intake among young children in child care has not been published. This article reviews the development and testing of a diet observation system for child care facilities that occurred during a larger intervention trial. Development of this system was divided into five phases, done in conjunction with a larger intervention study; (a) protocol development, (b) training of field staff, (c) certification of field staff in a laboratory setting, (d) implementation in a child-care setting, and (e) certification of field staff in a child-care setting. During the certification phases, methods were used to assess the accuracy and reliability of all observers at estimating types and amounts of food and beverages commonly served in child care. Tests of agreement show strong agreement among five observers, as well as strong accuracy between the observers and 20 measured portions of foods and beverages with a mean intraclass correlation coefficient value of 0.99. This structured observation system shows promise as a valid and reliable approach for assessing dietary intake of children in child care and makes a valuable contribution to the growing body of literature on the dietary assessment of young children.

  9. Method to Rapidly Collect Thousands of Velocity Observations to Validate Million-Element 2D Hydrodynamic Models

    NASA Astrophysics Data System (ADS)

    Barker, J. R.; Pasternack, G. B.; Bratovich, P.; Massa, D.; Reedy, G.; Johnson, T.

    2010-12-01

    Two-dimensional (depth-averaged) hydrodynamic models have existed for decades and are used to study a variety of hydrogeomorphic processes as well as to design river rehabilitation projects. Rapid computer and coding advances are revolutionizing the size and detail of 2D models. Meanwhile, advances in topo mapping and environmental informatics are providing the data inputs to drive large, detailed simulations. Million-element computational meshes are in hand. With simulations of this size and detail, the primary challenge has shifted to finding rapid and inexpensive means for testing model predictions against observations. Standard methods for collecting velocity data include boat-mounted ADCP and point-based sensors on boats or wading rods. These methods are labor intensive and often limited to a narrow flow range. Also, they generate small datasets at a few cross-sections, which is inadequate to characterize the statistical structure of the relation between predictions and observations. Drawing on the long-standing oceanographic method of using drogues to track water currents, previous studies have demonstrated the potential of small dGPS units to obtain surface velocity in rivers. However, dGPS is too inaccurate to test 2D models. Also, there is financial risk in losing drogues in rough currents. In this study, an RTK GPS unit was mounted onto a manned whitewater kayak. The boater positioned himself into the current and used floating debris to maintain a speed and heading consistent with the ambient surface flow field. RTK GPS measurements were taken ever 5 sec. From these positions, a 2D velocity vector was obtained. The method was tested over ~20 km of the lower Yuba River in California in flows ranging from 500-5000 cfs, yielding 5816 observations. To compare velocity magnitude against the 2D model-predicted depth-averaged value, kayak-based surface values were scaled down by an optimized constant (0.72), which had no negative effect on regression analysis

  10. Exploring the Ethics of Observational Research: The Case of an HIV Study in Tanzania

    PubMed Central

    Norris, Alison; Jackson, Ashley; Khoshnood, Kaveh

    2013-01-01

    Background Observational studies have generally been viewed as incurring minimal risk to participants, resulting in fewer ethical obligations for investigators than intervention studies. In 2004, the lead author (AN) carried out an observational study measuring sexual behavior and the prevalence of HIV, syphilis, and herpes simplex virus type 2 (HSV-2), among Tanzanian agricultural plantation residents (results reported elsewhere). This article uses an ethical lens to consider the consequences of the observational study and explore what, if any, effects it had on participants and their community. Methods Using a case study approach, we critically examine three core principles of research ethics—respect for persons/autonomy; beneficence/nonmaleficence; and distributive justice—as manifested in the 2004 observational study. We base our findings on three sources: discussions with plantation residents following presentations of observational research findings; in-depth interviews with key informants; and researcher observations. Results The observational research team was found to have ensured confidentiality and noncoercive recruitment. Ironically, maintenance of confidentiality and voluntary participation led some participants to doubt study results. Receiving HIV test results was important for participants and contributed to changing community norms about HIV testing. Conclusions Observational studies may act like de facto intervention studies and thus incur obligations similar to those of intervention studies. We found that ensuring respect for persons may have compromised the principles of beneficence and distributive justice. While in theory these three ethical principles have equal moral force, in practice, researchers may have to prioritize one over the others. Careful community engagement is necessary to promote well-considered ethical decisions. PMID:24069546

  11. Transient Mass-loss Analysis of Solar Observations Using Stellar Methods

    SciTech Connect

    Crosley, M. K.; Norman, C.; Osten, R. A.

    Low-frequency dynamic spectra of radio bursts from nearby stars offer the best chance to directly detect the stellar signature of transient mass loss on low-mass stars. Crosley et al. (2016) proposes a multi-wavelength methodology to determine coronal mass ejection (CME) parameters, such as speed, mass, and kinetic energy. We test the validity and accuracy of the results derived from the methodology by using Geostationary Operational Environmental Satellite X-ray observations and Bruny Island Radio Spectrometer radio observations. These are analogous observations to those that would be found in the stellar studies. Derived results from these observations are compared to direct whitemore » light measurements of the Large Angle and Spectrometric Coronagraph. We find that, when a pre-event temperature can be determined, the accuracy of CME speeds are within a few hundred km s{sup −1}, and are reliable when specific criteria has been met. CME mass and kinetic energies are only useful in determining the approximate order of magnitude measurements when considering the large errors associated to them. These results will be directly applicable to the interpretation of any detected stellar events and the derivation of stellar CME properties.« less

  12. Observation and Study of Proton Aurora by using Scanning Photometer

    NASA Astrophysics Data System (ADS)

    Mochizuki, T.; Ono, T.; Kadokura, A.; Sato, N.

    2009-12-01

    The proton auroras have significant differences from electron auroras in their spectral shape. They show Doppler-shifted and broadened spectra: the spectra have Doppler-shifted (~0.5 nm shorter) peak and both bluewing (~2-4 nm) and redwing (~1.5 nm) extending. Energy spectra of precipitating protons have been estimated from this shape. Recently it is found that the intensity in the extent of the blue wing reflects more effectively by the change of the mean energy of precipitating protons than the shift of peak wavelength [Lanchester et al., 2003]. Another character of the H-beta aurora is that it is diffuse form because a proton becomes hydrogen atom due to a charge-exchange reaction with atmospheric constituent and then possible to move across the magnetic field line. By using a scanning photometer, the movement of the proton auroral belt and change of a spectrum shape associated with the variation of proton source region due to storm and substorm were reported, however, not discussed in detail yet [Deehr and Lummerzheim, 2001]. The purpose of this study is to obtain the detail characteristics of H-beta aurora for understanding of source region of energetic protons in the magnetosphere. For this purpose, a new meridian-scanning photometer (SPM) was installed at Husafell station in Iceland in last summer season and Syowa Station, Antarctica. It will contribute to investigate the distribution of energetic protons and plasma waves which cause the pitch angle scattering in the magnetosphere. The meridian-scanning photometer is able to observe at five wavelengths for H-beta emission. One channel is to measure the background level. By analyzing the data obtained by the SPM, the H-beta spectrum can be estimated by fitting a model function with it. Then it is possible to obtain distribution of precipitating protons in north-south direction. It is also possible to estimate an energy spectrum of precipitating proton, simultaneously. The instrumental parameters of the SPM is

  13. [Efficacy observation of nonspecific low back pain treated with the dragon-tiger fighting needling method].

    PubMed

    Zhao, Feng; Cao, Dong-bo; Yuan, Yi-qin; Luo, Jian; Wen, Yan-yun; Wang, Yue; Yu, Jie

    2012-06-01

    To compare the difference in the clinical efficacy on nonspecific low back pain (NLBP) treated with the dragon-tiger fighting needling method, the uniform reinforcing-reducing method and the intermediate frequency physiotherapy. Ninety cases of NLBP were randomly divided into a dragon-tiger fighting needling group (group A), an uniform reinforcing-reducing needling group (group B) and an intermediate frequency physiotherapy group (group C), 30 cases in each one. In the group A, the dragon-tiger fighting needling method was used. In the group B, the uniform reinforcing-reducing method was applied. Two groups of acupoints were prescribed. One group included Shenshu (BL 23), Dachangshu (BL 25), Weizhong (BL 40) and Ashi points. The other group included Qihaishu (BL 24), Guanyuanshu (BL 26), Kunlun (BL 60), Yaoyangguan (GV 3). These two groups of acupoints were used alternatively in the above two groups. In the group C, the intermediate frequency physiotherapy was adopted in the pain area of the lumbar region. The treatment was given once per day in each group. Six treatments made one session. Totally, 2 sessions were required. The Visual Analogue Scale (VAS), the Oswestry Disability Index (ODD and the clinical efficacy were observed in each group. The scores of VAS and ODI were reduced obviously after treatment in each group (P < 0.05, P < 0.01). The score reducing in the group A was much more remarkable than those in the other two groups (all P < 0.05). The clinical curative rate was 30.0% (9/30), 23.3% (7/30) and 16.7% (5/30) in the group A, the group B and the group C, respectively. In comparison, the clinical efficacy in the group A was superior to that in either of the other groups (all P< 0.05). The dragon-tiger fighting needling method achieves the much better efficacy on NLBP compared with either the uniform reinforcing-reducing method or the intermediate frequency physiotherapy. It is one of the more effective needling method for analgesia.

  14. Temperature Variability during Delirium in ICU Patients: An Observational Study

    PubMed Central

    van der Kooi, Arendina W.; Kappen, Teus H.; Raijmakers, Rosa J.; Zaal, Irene J.; Slooter, Arjen J. C.

    2013-01-01

    Introduction Delirium is an acute disturbance of consciousness and cognition. It is a common disorder in the intensive care unit (ICU) and associated with impaired long-term outcome. Despite its frequency and impact, delirium is poorly recognized by ICU-physicians and –nurses using delirium screening tools. A completely new approach to detect delirium is to use monitoring of physiological alterations. Temperature variability, a measure for temperature regulation, could be an interesting component to monitor delirium, but whether temperature regulation is different during ICU delirium has not yet been investigated. The aim of this study was to investigate whether ICU delirium is related to temperature variability. Furthermore, we investigated whether ICU delirium is related to absolute body temperature. Methods We included patients who experienced both delirium and delirium free days during ICU stay, based on the Confusion Assessment method for the ICU conducted by a research- physician or –nurse, in combination with inspection of medical records. We excluded patients with conditions affecting thermal regulation or therapies affecting body temperature. Daily temperature variability was determined by computing the mean absolute second derivative of the temperature signal. Temperature variability (primary outcome) and absolute body temperature (secondary outcome) were compared between delirium- and non-delirium days with a linear mixed model and adjusted for daily mean Richmond Agitation and Sedation Scale scores and daily maximum Sequential Organ Failure Assessment scores. Results Temperature variability was increased during delirium-days compared to days without delirium (βunadjusted=0.007, 95% confidence interval (CI)=0.004 to 0.011, p<0.001). Adjustment for confounders did not alter this result (βadjusted=0.005, 95% CI=0.002 to 0.008, p<0.001). Delirium was not associated with absolute body temperature (βunadjusted=-0.03, 95% CI=-0.17 to 0.10, p=0.61). This

  15. An Observational Study of Antibiotic Prescribing Behavior and the Hawthorne Effect

    PubMed Central

    Mangione-Smith, Rita; Elliott, Marc N; McDonald, Laurie; McGlynn, Elizabeth A

    2002-01-01

    Objectives To assess whether prospective, observational study procedures, including questionnaires and audio recording, are associated with different patterns of physician diagnostic decision making and antibiotic prescribing. Data Sources/Setting (1) Survey data from a prospective observational study of treatment patterns for children with acute upper respiratory illnesses (10/96–3/97) and (2) retrospective medical record abstraction data of nonobserved encounters for the same problems occurring during (10/96–3/97) and one year after (10/97–3/98) the observational study period. Ten pediatricians in two community practices were studied. Study Design Patterns of diagnoses recorded in the medical record and antibiotics ordered for visits occurring outside of the observational study (same time period and one year later) were compared with the pattern of diagnoses and antibiotics ordered during the observational study. Data Collection/Extraction Methods For the observational study (10/96–2/97), diagnosis and treatment choices were obtained from questionnaires completed by physicians immediately following the visit. For the nonstudy encounters (10/96–3/97 and 10/97–3/98), data were abstracted from medical records one year after the observational study was completed. Principal Findings The proportion of viral cases in which an antibiotic was prescribed was 29 percentage points lower for the observational study compared to the retrospective analysis (p <.05). In one of two study sites, the proportion of cases assigned a bacterial diagnosis was 29 percentage points lower in the observational study period compared to the retrospective study (p <.05). Conclusions Observational study procedures including questionnaires and audio recording can affect antibiotic prescribing behavior. Future observational studies aimed at examining the frequency of inappropriate antibiotic prescribing should measure and adjust for the Hawthorne effect; without such adjustments, the

  16. Statistical methods for studying disease subtype heterogeneity.

    PubMed

    Wang, Molin; Spiegelman, Donna; Kuchiba, Aya; Lochhead, Paul; Kim, Sehee; Chan, Andrew T; Poole, Elizabeth M; Tamimi, Rulla; Tworoger, Shelley S; Giovannucci, Edward; Rosner, Bernard; Ogino, Shuji

    2016-02-28

    A fundamental goal of epidemiologic research is to investigate the relationship between exposures and disease risk. Cases of the disease are often considered a single outcome and assumed to share a common etiology. However, evidence indicates that many human diseases arise and evolve through a range of heterogeneous molecular pathologic processes, influenced by diverse exposures. Pathogenic heterogeneity has been considered in various neoplasms such as colorectal, lung, prostate, and breast cancers, leukemia and lymphoma, and non-neoplastic diseases, including obesity, type II diabetes, glaucoma, stroke, cardiovascular disease, autism, and autoimmune disease. In this article, we discuss analytic options for studying disease subtype heterogeneity, emphasizing methods for evaluating whether the association of a potential risk factor with disease varies by disease subtype. Methods are described for scenarios where disease subtypes are categorical and ordinal and for cohort studies, matched and unmatched case-control studies, and case-case study designs. For illustration, we apply the methods to a molecular pathological epidemiology study of alcohol intake and colon cancer risk by tumor LINE-1 methylation subtypes. User-friendly software to implement the methods is publicly available. Copyright © 2015 John Wiley & Sons, Ltd.

  17. Results of Observational Studies: Analysis of Findings from the Nurses’ Health Study

    PubMed Central

    Tai, Vicky; Grey, Andrew; Bolland, Mark J.

    2014-01-01

    Background The role of observational studies in informing clinical practice is debated, and high profile examples of discrepancies between the results of observational studies and randomised controlled trials (RCTs) have intensified that debate. We systematically reviewed findings from the Nurses’ Health Study (NHS), one of the longest and largest observational studies, to assess the number and strength of the associations reported and to determine if they have been confirmed in RCTs. Methods We reviewed NHS publication abstracts from 1978–2012, extracted information on associations tested, and graded the strength of the reported effect sizes. We searched PubMed for RCTs or systematic reviews for 3 health outcomes commonly reported in NHS publications: breast cancer, ischaemic heart disease (IHD) and osteoporosis. NHS results were compared with RCT results and deemed concordant when the difference in effect sizes between studies was ≤0.15. Findings 2007 associations between health outcomes and independent variables were reported in 1053 abstracts. 58.0% (1165/2007) were statistically significant, and 22.2% (445/2007) were neutral (no association). Among the statistically significant results that reported a numeric odds ratio (OR) or relative risk (RR), 70.5% (706/1002) reported a weak association (OR/RR 0.5–2.0), 24.5% (246/1002) a moderate association (OR/RR 0.25–0.5 or 2.0–4.0) and 5.0% (50/1002) a strong association (OR/RR ≤0.25 or ≥4.0). 19 associations reported in NHS publications for breast cancer, IHD and osteoporosis have been tested in RCTs, and the concordance between NHS and RCT results was low (≤25%). Conclusions NHS publications contain a large number of analyses, the majority of which reported statistically significant but weak associations. Few of these associations have been tested in RCTs, and where they have, the agreement between NHS results and RCTs is poor. PMID:25330007

  18. The ALFA (Activity Log Files Aggregation) Toolkit: A Method for Precise Observation of the Consultation

    PubMed Central

    2008-01-01

    Background There is a lack of tools to evaluate and compare Electronic patient record (EPR) systems to inform a rational choice or development agenda. Objective To develop a tool kit to measure the impact of different EPR system features on the consultation. Methods We first developed a specification to overcome the limitations of existing methods. We divided this into work packages: (1) developing a method to display multichannel video of the consultation; (2) code and measure activities, including computer use and verbal interactions; (3) automate the capture of nonverbal interactions; (4) aggregate multiple observations into a single navigable output; and (5) produce an output interpretable by software developers. We piloted this method by filming live consultations (n = 22) by 4 general practitioners (GPs) using different EPR systems. We compared the time taken and variations during coded data entry, prescribing, and blood pressure (BP) recording. We used nonparametric tests to make statistical comparisons. We contrasted methods of BP recording using Unified Modeling Language (UML) sequence diagrams. Results We found that 4 channels of video were optimal. We identified an existing application for manual coding of video output. We developed in-house tools for capturing use of keyboard and mouse and to time stamp speech. The transcript is then typed within this time stamp. Although we managed to capture body language using pattern recognition software, we were unable to use this data quantitatively. We loaded these observational outputs into our aggregation tool, which allows simultaneous navigation and viewing of multiple files. This also creates a single exportable file in XML format, which we used to develop UML sequence diagrams. In our pilot, the GP using the EMIS LV (Egton Medical Information Systems Limited, Leeds, UK) system took the longest time to code data (mean 11.5 s, 95% CI 8.7-14.2). Nonparametric comparison of EMIS LV with the other systems showed

  19. A Comparison of Observed Abundances in Five Well-Studied Planetary Nebulae

    NASA Astrophysics Data System (ADS)

    Tanner, Jolene; Balick, B.; Kwitter, K. B.

    2013-01-01

    We have assembled data and derived abundances in several recent careful studies for five bright planetary nebulae (PNe) of low, moderate, and high ionization and relatively simple morphology. Each of the studies employ different apertures, aperture placement, and facilities for the observations. Various methods were used to derive total abundances. All used spectral windows that included [OII]3727 in the UV through Argon lines in the red. Our ultimate goal is to determine the extent to which the derived abundances are consistent. We show that the reddening-corrected line ratios are surprisingly similar despite the different modes of observation and that the various abundance analysis methods yield generally consistent results for He/H, N/H, O/H, and Ne/H (within 50% with a few larger deviations). In addition we processed the line ratios from the different sources using a common abundance derivation method (ELSA) to search for clues of systematic methodological inconsistencies. None were uncovered.

  20. An observational study of the initial management of hypothyroidism in France: the ORCHIDÉE study

    PubMed Central

    Delemer, Brigitte; Aubert, Jean-Pierre; Nys, Pierre; Landron, Frédéric; Bouée, Stéphane

    2012-01-01

    Objective To document the initial management of hypothyroidism in France with respect to diagnostic setting, investigations, and therapeutic approach. Design Observational study of the management by primary care practitioners (PCPs) and endocrinologists of patients diagnosed with, and treated for, hypothyroidism during the enrollment period or the previous 6 months. Methods A representative sample of PCPs and endocrinologists enrolled up to five consecutive patients and reported sociodemographic, clinical, therapeutic, and laboratory data. Data were submitted at baseline and at the first measurement of TSH after starting the treatment. Results The analysis population comprised 1255 patients (mean (s.d.) age 52.8 (16.3) years; 84% female). Hypothyroidism was suspected on clinical grounds in 77% of patients, with goiter in 16%. Autoimmune thyroiditis, supported by positive anti-thyroid antibodies, was the most frequent diagnosis (59%), followed by iatrogenic causes (28%), of which thyroidectomy was the most common. The median baseline TSH was 8.6 mIU/l, suggesting a high incidence of subclinical hypothyroidism. Imaging studies were requested in over 75% of patients, with ultrasound performed in 98% and scintigraphy performed in 19% of these patients. Both groups of physicians treated their patients almost exclusively with levothyroxine. Endocrinologists were more likely than PCPs to provide counseling on how to take medication correctly. Conclusions This observational study of a large cohort of patients with newly diagnosed hypothyroidism in France illustrates current practice and indicates some areas where physician education may be required to optimize adherence to guidelines and cost-effectiveness. PMID:23034782

  1. Using direct clinical observation to assess the quality of cesarean delivery in Afghanistan: an exploratory study

    PubMed Central

    2014-01-01

    Background As part of a National Emergency Obstetric and Newborn Care (EmONC) Needs Assessment, a special study was undertaken in July 2010 to examine the quality of cesarean deliveries in Afghanistan and examine the utility of direct clinical observation as an assessment method in low-resource settings. Methods This cross-sectional assessment of the quality of cesareans at 14 facilities in Afghanistan included a survey of surgeons regarding their routine cesarean practices, direct observation of 29 cesarean deliveries and comparison of observations with facility records for 34 additional cesareans conducted during the 3 days prior to the observation period at each facility. For both observed cases and record reviews, we assessed time intervals between specified points of care-arrival to the ward, first evaluation, detection of a complication, decision for cesarean, incision, and birth. Results All time intervals with the exception of “decision to skin incision” were longer in the record reviews than in observed cases. Prior cesarean was the most common primary indication for all cases. All mothers in both groups observed survived through one hour postpartum. Among newborns there were two stillbirths (7%) in observed births and seven (21%) record reviews. Although our sample is too small to show statistical significance, the difference is noteworthy. In six of the reviewed cesareans resulting in stillbirth, a fetal heart rate was recorded in the operating theater, although four were recorded as macerated. For the two fresh stillbirths, the cesarean surgeries were recorded as scheduled and not urgent. Conclusions Direct observation of cesarean deliveries enabled us to assess a number of preoperative, postoperative, and intraoperative procedures that are often not described in medical records in low resource settings. Comparison of observations with findings from provider interviews and facility records allowed us to infer whether observed practices were typical

  2. Survey and Chase: A New Method of Observations For The Michigan Orbital Debris Survey Telescope (MODEST)

    NASA Technical Reports Server (NTRS)

    Abercromby, Kira J.; Seitzer, Patrick; Rodriquez, Heather M.; Barker, Edwin S.; Matney, Mark J.

    2006-01-01

    For more than 40 years astronauts have been observing Earth, taking photographs or digital images from their spacecraft. Today, a robust program of observation from the International Space Station (ISS) has yielded hundreds of thousands of images of the Earth s surface collected since 2001. Seeing Earth through the eyes of an astronaut is exciting to the general public, and the images are popular in classrooms. Because the ISS has an orbital inclination of 51.6 degrees (the north-south limits of the orbit are at 51.6 degrees latitude), high latitude observations are common. Some of the most striking images collected include views of polar phenomena. Astronauts routinely pass above brilliant red and green aurora; view high, wispy clouds at the top of the atmosphere; or look down on glaciers and floating ice rafts. These images, framed and captured by humans, are easily interpreted by students and teachers. Astronaut observations provide a way to visualize complicated polar phenomena and communicate about them to students of all ages. Over the next two years, astronauts aboard the ISS will formally focus their observations on polar phenomena as participants in the International Polar Year (IPY). Imagery acquisition from the ISS will be coordinated with other IPY scientists staging studies and field campaigns on the ground. The imagery collected from the ISS will be cataloged and served on NASA s web-based database of images, http://eol.jsc.nasa.gov . The website allows investigators, students and teachers to search through the imagery, assemble image datasets, and download the imagery and the metadata. We display some of the most spectacular examples of polar imagery and demonstrate NASA s database of astronaut images of Earth.

  3. Temporomandibular Disorders in Burning Mouth Syndrome Patients: An Observational Study

    PubMed Central

    Corsalini, Massimo; Di Venere, Daniela; Pettini, Francesco; Lauritano, Dorina; Petruzzi, Massimo

    2013-01-01

    BACKGROUND: Burning Mouth Syndrome (BMS) is a chronic disease characterized by absence of any lesions and burning of the oral mucosa associated to a sensation of dry mouth and/or taste alterations. The purpose of our study is to estimate signs and symptoms of Temporomandibular Disorders (TMD) in patients with BMS and to investigate for the existence of an association between BMS and TMD. MATERIALS AND METHODS: Forty-four BMS patients were enrolled; BMS subtype was established according to the classification of Lamey. After a gnathological evaluation, according to the protocol of the European Academy of Craniomandibular Disorders, patients were classified by RDC/TMD criteria. The data were compared and analyzed using a chi-square test to describe the existence of an association between BMS and TMD. RESULTS: 65.9% the BMS patients showed disorders classified as primary signs and symptoms of TMD according to RDC / TMD criteria, and 72.7% showed parafunctional habits. The chi-square test revealed a statistically significant association (p = 0.035) between BMS and TMD. CONCLUSION: The data suggest that there is a possible relationship not yet well understood between BMS and TMD, may be for neurophatic alterations assumed for BMS that could be also engaged in TMD pathogenesis. PMID:24273452

  4. Study of P -wave excitations of observed charmed strange baryons

    NASA Astrophysics Data System (ADS)

    Ye, Dan-Dan; Zhao, Ze; Zhang, Ailin

    2017-12-01

    Many excited charmed strange baryons such as Ξc(2790 ), Ξc(2815 ), Ξc(2930 ), Ξc(2980 ), Ξc(3055 ), Ξc(3080 ), and Ξc(3123 ) have been observed. In order to understand their internal structure and to determine their spin parities, the strong decay properties of these baryons as possible P -wave excited Ξc candidates have been systematically studied in a 3P0 model. The configurations and JP assignments of Ξc(2790 ), Ξc(2815 ), Ξc(2930 ), Ξc(2980 ), Ξc(3055 ), Ξc(3080 ), and Ξc(3123 ) have been explored based on recent experimental data. In our analyses, Ξc(3055 ), Ξc(3080 ), and Ξc(3123 ) seem impossible to be the P -wave excited Ξc. Ξc(2790 ), Ξc(2815 ), Ξc(2930 ), and Ξc(2980 ) may be the P -wave excited Ξc. In particular, Ξc(2790 ) and Ξc(2815 ) are very possibly the P -wave excited Ξc 1(1 /2-) and Ξc 1(3 /2-), respectively. Ξc(2980 ) may be the P -wave excited Ξc1 '(1/2-). Ξc(2930 ) may be the P -wave Ξc0 '(1/2-) , Ξ˜c 0(1/2-), Ξc2 '(3/2-), Ξc2 '(5/2-), Ξ˜c 2(3/2-), or Ξ˜c 2(5/2-). Furthermore, some branching fraction ratios related to the internal structure and quark configuration of P -wave Ξc have also been computed. Measurements of these ratios in the future will be helpful to understand these excited Ξc.

  5. Observational study of treatment space in individual neonatal cot spaces.

    PubMed

    Hignett, Sue; Lu, Jun; Fray, Mike

    2010-01-01

    Technology developments in neonatal intensive care units have increased the spatial requirements for clinical activities. Because the effectiveness of healthcare delivery is determined in part by the design of the physical environment and the spatial organization of work, it is appropriate to apply an evidence-based approach to architectural design. This study aimed to provide empirical evidence of the spatial requirements for an individual cot or incubator space. Observational data from 2 simulation exercises were combined with an expert review to produce a final recommendation. A validated 5-step protocol was used to collect data. Step 1 defined the clinical specialty and space. In step 2, data were collected with 28 staff members and 15 neonates to produce a simulation scenario representing the frequent and safety-critical activities. In step 3, 21 staff members participated in functional space experiments to determine the average spatial requirements. Step 4 incorporated additional data (eg, storage and circulation) to produce a spatial recommendation. Finally, the recommendation was reviewed in step 5 by a national expert clinical panel to consider alternative layouts and technology. The average space requirement for an individual neonatal intensive care unit cot (incubator) space was 13.5 m2 (or 145.3 ft2). The circulation and storage space requirements added in step 4 increased this to 18.46 m2 (or 198.7 ft2). The expert panel reviewed the recommendation and agreed that the average individual cot space (13.5 m2/[or 145.3 ft2]) would accommodate variance in working practices. Care needs to be taken when extrapolating this recommendation to multiple cot areas to maintain the minimum spatial requirement.

  6. Parameter estimation method that directly compares gravitational wave observations to numerical relativity

    NASA Astrophysics Data System (ADS)

    Lange, J.; O'Shaughnessy, R.; Boyle, M.; Calderón Bustillo, J.; Campanelli, M.; Chu, T.; Clark, J. A.; Demos, N.; Fong, H.; Healy, J.; Hemberger, D. A.; Hinder, I.; Jani, K.; Khamesra, B.; Kidder, L. E.; Kumar, P.; Laguna, P.; Lousto, C. O.; Lovelace, G.; Ossokine, S.; Pfeiffer, H.; Scheel, M. A.; Shoemaker, D. M.; Szilagyi, B.; Teukolsky, S.; Zlochower, Y.

    2017-11-01

    We present and assess a Bayesian method to interpret gravitational wave signals from binary black holes. Our method directly compares gravitational wave data to numerical relativity (NR) simulations. In this study, we present a detailed investigation of the systematic and statistical parameter estimation errors of this method. This procedure bypasses approximations used in semianalytical models for compact binary coalescence. In this work, we use the full posterior parameter distribution for only generic nonprecessing binaries, drawing inferences away from the set of NR simulations used, via interpolation of a single scalar quantity (the marginalized log likelihood, ln L ) evaluated by comparing data to nonprecessing binary black hole simulations. We also compare the data to generic simulations, and discuss the effectiveness of this procedure for generic sources. We specifically assess the impact of higher order modes, repeating our interpretation with both l ≤2 as well as l ≤3 harmonic modes. Using the l ≤3 higher modes, we gain more information from the signal and can better constrain the parameters of the gravitational wave signal. We assess and quantify several sources of systematic error that our procedure could introduce, including simulation resolution and duration; most are negligible. We show through examples that our method can recover the parameters for equal mass, zero spin, GW150914-like, and unequal mass, precessing spin sources. Our study of this new parameter estimation method demonstrates that we can quantify and understand the systematic and statistical error. This method allows us to use higher order modes from numerical relativity simulations to better constrain the black hole binary parameters.

  7. Data Quality Assessment of In Situ and Altimeter Observations Through Two-Way Intercomparison Methods

    NASA Astrophysics Data System (ADS)

    Guinehut, Stephanie; Valladeau, Guillaume; Legeais, Jean-Francois; Rio, Marie-Helene; Ablain, Michael; Larnicol, Gilles

    2013-09-01

    This proceeding presents an overview of the two-way inter-comparison activities performed at CLS for both space and in situ observation agencies and why this activity is a required step to obtain accurate and homogenous data sets that can then be used together for climate studies or in assimilation/validation tools. We first describe the work performed in the frame of the SALP program to assess the stability of altimeter missions through SSH comparisons with tide gauges (GLOSS/CLIVAR network). Then, we show how the SSH comparison between the Argo array and altimeter time series allows the detection of drifts or jumps in altimeter (SALP program) but also for some Argo floats (Ifremer/Coriolis center). Lastly, we describe how the combine use of altimeter and wind observations helps the detection of drogue loss of surface drifting buoys (GDP network) and allow the computation of a correction term for wind slippage.

  8. Right Iliac Fossa Pain Treatment (RIFT) Study: protocol for an international, multicentre, prospective observational study

    PubMed Central

    2018-01-01

    Introduction Patients presenting with right iliac fossa (RIF) pain are a common challenge for acute general surgical services. Given the range of potential pathologies, RIF pain creates diagnostic uncertainty and there is subsequent variation in investigation and management. Appendicitis is a diagnosis which must be considered in all patients with RIF pain; however, over a fifth of patients undergoing appendicectomy, in the UK, have been proven to have a histologically normal appendix (negative appendicectomy). The primary aim of this study is to determine the contemporary negative appendicectomy rate. The study’s secondary aims are to determine the rate of laparoscopy for appendicitis and to validate the Appendicitis Inflammatory Response (AIR) and Alvarado prediction scores. Methods and analysis This multicentre, international prospective observational study will include all patients referred to surgical specialists with either RIF pain or suspected appendicitis. Consecutive patients presenting within 2-week long data collection periods will be included. Centres will be invited to participate in up to four data collection periods between February and August 2017. Data will be captured using a secure online data management system. A centre survey will profile local policy and service delivery for management of RIF pain. Ethics and dissemination Research ethics are not required for this study in the UK, as determined using the National Research Ethics Service decision tool. This study will be registered as a clinical audit in participating UK centres. National leads in countries outside the UK will oversee appropriate registration and study approval, which may include completing full ethical review. The study will be disseminated by trainee-led research collaboratives and through social media. Peer-reviewed publications will be published under corporate authorship including ‘RIFT Study Group’ and ‘West Midlands Research Collaborative’. PMID:29331965