Science.gov

Sample records for observational studies methods

  1. Problematising Short-Term Participant Observation and Multi-Method Ethnographic Studies

    ERIC Educational Resources Information Center

    Brockmann, Michaela

    2011-01-01

    This article reports on a study of apprentices in England and Germany designed to explore young people's learner identities over time and in relation to particular learning environments. The research adopts a multi-method ethnographic approach, combining biographical interviews with multi-site participant observation. The article problematises the…

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

    PubMed Central

    2016-01-01

    OBJECTIVES: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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. PMID:26797219

  3. 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.

  4. 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

  5. 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.

  6. 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).

  7. Consistency across Methods of Observation -- An In-Depth Study of the Cognitive Preference Test.

    ERIC Educational Resources Information Center

    Jungwirth, Ehud

    1983-01-01

    Two response formats and request for reason-for-choice on a traditional cognitive preference test (CPT) and an open-ended CPT were used to test for consistency across methods of observation at individual/population levels. Results indicate that validation of CPT constructs has not reached state of unequivocality necessary for their application in…

  8. 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 peak 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.

  9. 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…

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

    NASA Technical Reports Server (NTRS)

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

    1990-01-01

    Using nightside electron density profiles obtained with radio occultation data from the Viking orbiters, the nightside ionospheres of Mars and Venus are investigated. It is shown that the Mars nightside ionosphere is generally weaker than the Venus nightside ionosphere, and, when it is present, the peak altitude is higher. Otherwise, there is considerable similarity. In particular, the dependence of peak density on solar zenith angle in the range of the Viking nightside observations (90-130 deg) is found to be similar for both planets.

  11. Evaluation of Teaching Methods in Mass CPCR Training in Different Groups of the Society, an Observational Study.

    PubMed

    Hasani, Hamed; Bahrami, Mojtaba; Malekpour, Abdorrasoul; Dehghani, Mohammadreza; Allahyary, Elaheh; Amini, Mitra; Abdorahimi, Mehdi; khani, Sara; Kalantari Meibodi, Mohammad; Kojuri, Javad

    2015-05-01

    To determine the efficacy of different methods of cardiopulmonary resuscitation (CPCR) training in 3 different groups of the society. In a prospective and observational study of 2000 individuals in 3 different groups including G1, G2, and G3 4 different protocols of CPCR training were applied and their efficacy was compared between the groups. Also, 12 months after the study course, 460 participants from 3 groups were asked to take apart in a theoretical and practical examination to evaluate the long-term efficacy of the 4 protocols. Among 2000 individuals took a parted in the study, 950 (47.5%) were G1, 600 (30%) were G2, and 450 (22.5%) were G3. G1 in 4 groups were 2.37 and 2.65 times more successful in pretest theoretical and 2.61 and 18.20 times more successful in practical examinations compared with G2 and G3 and gained highest improvement in CPCR skills. Other groups also showed significantly improved CPCR skills. Comparison of different methods of CPCR learning showed that the workshop using interactive lecture as well as human model, educational film, and reference CPCR book has the highest efficacy in all groups. This protocol of CPCR training showed more efficacy in long-term postdelayed evaluation. On the contrary, medical students had better long-term outcomes from the course. Although G1 and G2 obtained better results in learning CPCR skills, in G3 also the theoretical and practical knowledge were improved significantly. This course increased confidence for doing CPCR in all groups of the study. Considering that the most of the bystanders at emergency states are general population, training this group of the society and increasing their confidence about performing CPCR can be so effective and lifesaving at emergency states. (Clinical trial. Gov registration: NCT02120573).

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

    PubMed Central

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

    2016-01-01

    Introduction 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. Methods and analysis 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. Ethics and dissemination 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

  13. Evaluation of Teaching Methods in Mass CPCR Training in Different Groups of the Society, an Observational Study

    PubMed Central

    Hasani, Hamed; Bahrami, Mojtaba; Malekpour, Abdorrasoul; Dehghani, Mohammadreza; Allahyary, Elaheh; Amini, Mitra; Abdorahimi, Mehdi; khani, Sara; Kalantari Meibodi, Mohammad; Kojuri, Javad

    2015-01-01

    Abstract To determine the efficacy of different methods of cardiopulmonary resuscitation (CPCR) training in 3 different groups of the society. In a prospective and observational study of 2000 individuals in 3 different groups including G1, G2, and G3 4 different protocols of CPCR training were applied and their efficacy was compared between the groups. Also, 12 months after the study course, 460 participants from 3 groups were asked to take apart in a theoretical and practical examination to evaluate the long-term efficacy of the 4 protocols. Among 2000 individuals took a parted in the study, 950 (47.5%) were G1, 600 (30%) were G2, and 450 (22.5%) were G3. G1 in 4 groups were 2.37 and 2.65 times more successful in pretest theoretical and 2.61 and 18.20 times more successful in practical examinations compared with G2 and G3 and gained highest improvement in CPCR skills. Other groups also showed significantly improved CPCR skills. Comparison of different methods of CPCR learning showed that the workshop using interactive lecture as well as human model, educational film, and reference CPCR book has the highest efficacy in all groups. This protocol of CPCR training showed more efficacy in long-term postdelayed evaluation. On the contrary, medical students had better long-term outcomes from the course. Although G1 and G2 obtained better results in learning CPCR skills, in G3 also the theoretical and practical knowledge were improved significantly. This course increased confidence for doing CPCR in all groups of the study. Considering that the most of the bystanders at emergency states are general population, training this group of the society and increasing their confidence about performing CPCR can be so effective and lifesaving at emergency states. (Clinical trial. Gov registration: NCT02120573) PMID:26020392

  14. 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

  15. Skylab Earth Observation Studies

    NASA Technical Reports Server (NTRS)

    1972-01-01

    This concept illustrates Skylab Earth observation studies, an Earth Resources Experiment Package (EREP). EREP was designed to explore the use of the widest possible portion of the electromagnetic spectrum for Earth resource investigations with sensors that recorded data in the visible, infrared, and microwave spectral regions. Resources subject to this study included a capability of mapping Earth resources and land uses, crop and forestry cover, health of vegetation, types of soil, water storage in snow pack, surface or near-surface mineral deposits, sea surface temperature, and the location of likely feeding areas for fish, etc. A significant feature of EREP was the ability of man to operate the sensors in a laboratory fashion.

  16. 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. PMID:24033245

  17. Using observational methods in nursing research.

    PubMed

    Salmon, Jenny

    2015-07-01

    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.

  18. HARPS Observes the Earth Transiting the Sun — A Method to Study Exoplanet Atmospheres Using Precision Spectroscopy on Large Ground-based Telescopes

    NASA Astrophysics Data System (ADS)

    Yan, F.; Fosbury, R.; Petr-Gotzens, M.; Pallé, E.; Zhao, G.

    2015-09-01

    Exoplanetary transits offer the opportunity to measure the transmission of long, tangential pathlengths through their atmospheres. Since the fraction of the observed stellar light taking these paths is very small, transit photometric and spectrophotometric measurements of light curves require very high levels of measurement stability, favouring the use of intrinsically stable space telescopes. By studying the Rossiter-McLaughlin effect on the radial velocity of the transited star, pure, high-precision radial velocity measurements can be used to estimate the changes in planetary atmospheric transmission with wavelength: a promising method for future studies of small planets with very large ground-based telescopes since it removes the requirement for extreme photometric stability. This article describes a successful feasibility experiment using the HARPS instrument to measure reflected moonlight during the penumbral phases of a Lunar eclipse, effectively providing an observation of an Earth transit.

  19. Assessing observational studies of medical treatments

    PubMed Central

    Hartz, Arthur; Bentler, Suzanne; Charlton, Mary; Lanska, Douglas; Butani, Yogita; Soomro, G Mustafa; Benson, Kjell

    2005-01-01

    Background Previous studies have assessed the validity of the observational study design by comparing results of studies using this design to results from randomized controlled trials. The present study examined design features of observational studies that could have influenced these comparisons. Methods To find at least 4 observational studies that evaluated the same treatment, we reviewed meta-analyses comparing observational studies and randomized controlled trials for the assessment of medical treatments. Details critical for interpretation of these studies were abstracted and analyzed qualitatively. Results Individual articles reviewed included 61 observational studies that assessed 10 treatment comparisons evaluated in two studies comparing randomized controlled trials and observational studies. The majority of studies did not report the following information: details of primary and ancillary treatments, outcome definitions, length of follow-up, inclusion/exclusion criteria, patient characteristics relevant to prognosis or treatment response, or assessment of possible confounding. When information was reported, variations in treatment specifics, outcome definition or confounding were identified as possible causes of differences between observational studies and randomized controlled trials, and of heterogeneity in observational studies. Conclusion Reporting of observational studies of medical treatments was often inadequate to compare study designs or allow other meaningful interpretation of results. All observational studies should report details of treatment, outcome assessment, patient characteristics, and confounding assessment. PMID:16137327

  20. A method to analyse observer disagreement in visual grading studies: example of assessed image quality in paediatric cerebral multidetector CT images.

    PubMed

    Ledenius, K; Svensson, E; Stålhammar, F; Wiklund, L-M; Thilander-Klang, A

    2010-07-01

    The purpose was to demonstrate a non-parametric statistical method that can identify and explain the components of observer disagreement in terms of systematic disagreement as well as additional individual variability, in visual grading studies. As an example, the method was applied to a study where the effect of reduced tube current on diagnostic image quality in paediatric cerebral multidetector CT (MDCT) images was investigated. Quantum noise, representing dose reductions equivalent to steps of 20 mA, was artificially added to the raw data of 25 retrospectively selected paediatric cerebral MDCT examinations. Three radiologists, blindly and randomly, assessed the resulting images from two different levels of the brain with regard to the reproduction of high- and low-contrast structures and overall image quality. Images from three patients were assessed twice for the analysis of intra-observer disagreement. The intra-observer disagreement in test-retest assessments could mainly be explained by a systematic change towards lower image quality the second time the image was reviewed. The inter-observer comparisons showed that the paediatric radiologist was more critical of the overall image quality, while the neuroradiologists were more critical of the reproduction of the basal ganglia. Differences between the radiologists regarding the extent to which they used the whole classification scale were also found. The statistical method used was able to identify and separately measure a presence of bias apart from additional individual variability within and between the radiologists which is, at the time of writing, not attainable by any other statistical approach suitable for paired, ordinal data.

  1. A new method using medical ultrasound for measuring femoral anteversion (torsion): technique and reliability. An intra-observer and inter-observer study on dried bones from human adults.

    PubMed Central

    Upadhyay, S S; O'Neil, T; Burwell, R G; Moulton, A

    1987-01-01

    The purpose of this study was to evaluate an ultrasound method on dried femora to decide if it is sufficiently reliable to consider its application to living subjects in health and disease. It reports the application of a standard static image B-mode ultrasound scanner to measure femoral anteversion (strictly torsion) on dried bones. The method involves creating images of bony surface contours at both the upper and the lower ends of the femur placed in a water bath. The calculation of femoral torsion involves measuring the angular difference between a head-neck line at the upper end and a transcondylar line at the lower end of the femur. This approach, using the surface contour of the bone at the upper end of the femur, is similar to that used by Lange & Pitzen (1921) and differs from conventional ways of measuring anteversion in dried bones using a central femoral head-neck axis. It is shown that in ultrasound scanning of the upper end of the dried femur to measure femoral anteversion, the head-neck line must be at, or rostral to, the base of greater trochanter. The intra- and inter-observer reliability was assessed in 10 femora, each scanned ten times by two observers. It is shown that femoral torsion can be measured by the ultrasound method to an accuracy of +/- 2 degrees (95% confidence limits) without a significant difference between the observers. The ultrasound method is compared with a new mechanical method for creating surface contours at both ends of the femur and found not to be statistically different in 37 femora. Two real-time ultrasound methods reported by other workers for measuring femoral anteversion in dried bones are reviewed. It is suggested that in applying ultrasound to measure femoral anteversion in living subjects, the B-mode static image scanner is superior to the use of real-time scanners. Images Fig. 1 Fig. 2 Fig. 4 Fig. 5 PMID:3332271

  2. Comparison of treatment effect estimates of non-vitamin K antagonist oral anticoagulants versus warfarin between observational studies using propensity score methods and randomized controlled trials.

    PubMed

    Li, Guowei; Holbrook, Anne; Jin, Yanling; Zhang, Yonghong; Levine, Mitchell A H; Mbuagbaw, Lawrence; Witt, Daniel M; Crowther, Mark; Connolly, Stuart; Chai-Adisaksopha, Chatree; Wan, Zhongxiao; Cheng, Ji; Thabane, Lehana

    2016-06-01

    Emerging observational studies using propensity score (PS) methods assessed real-world comparative effectiveness of non-vitamin K antagonist oral anticoagulants (NOACs) versus warfarin in patients with non-valvular atrial fibrillation (AF). We aimed to compare treatment effect estimates of NOACs between PS studies and randomized controlled trials (RCTs). Electronic databases and conference proceedings were searched systematically. Primary outcomes included stroke or systemic embolism (SE) and major bleeding. A random-effects meta-analysis was performed to synthesize the data by pooling the PS- and RCT-derived hazard ratios (HRs) separately. The ratio of HRs (RHR) from the ratio of PS-derived HRs relative to RCT-derived HRs was used to determine whether there was a difference between estimates from PS studies and RCTs. There were 10 PS studies and 5 RCTs included for analysis. No significant difference of treatment effect estimates between the PS studies and RCTs was observed: RHR 1.11, 95 % CI 0.98-1.23 for stroke or SE; RHR 1.07, 95 % CI 0.87-1.34 for major bleeding. A significant association between NOACs and risk of stroke or SE was observed: HR 0.88, 95 % CI 0.83-0.94 for the PS studies; HR 0.79, 95 % CI 0.72-0.87 for the RCTs. However, no relationship between NOACs and risk of major bleeding was found: HR 0.91, 95 % CI 0.79-1.05 for the PS studies; HR 0.85, 95 % CI 0.73-1.00 for the RCTs. In this study, treatment effect estimates of NOACs versus warfarin in patients with non-valvular AF from PS studies are found to be in agreement with those from RCTs. PMID:27370013

  3. Occupational stressors and hypertension: a multi-method study using observer-based job analysis and self-reports in urban transit operators.

    PubMed

    Greiner, Birgit A; Krause, Niklas; Ragland, David; Fisher, June M

    2004-09-01

    This multi-method study aimed to disentangle objective and subjective components of job stressors and determine the role of each for hypertension risk. Because research on job stressors and hypertension has been exclusively based on self-reports of stressors, the tendency of some individuals to use denial and repressive coping might be responsible for the inconclusive results in previous studies. Stressor measures with different degrees of objectivity were contrasted, including (1) an observer-based measure of stressors (job barriers, time pressure) obtained from experts, (2) self-reported frequency and appraised intensity of job problems and time pressures averaged per workplace (group level), (3) self-reported frequency of job problems and time pressures at the individual level, and (4) self-reported appraised intensity of job problems and time pressures at the individual level. The sample consisted of 274 transit operators working on 27 different transit lines and four different vehicle types. Objective stressors (job barriers and time pressure) were each significantly associated with hypertension (casual blood pressure readings and/or currently taking anti-hypertensive medication) after adjustment for age, gender and seniority. Self-reported stressors at the individual level were positively but not significantly associated with hypertension. At the group level, only appraisal of job problems significantly predicted hypertension. In a composite regression model, both observer-based job barriers and self-reported intensity of job problems were independently and significantly associated with hypertension. Associations between self-reported job problems (individual level) and hypertension were dependent on the level of objective stressors. When observer-based stressor level was low, the association between self-reported frequency of stressors and hypertension was high. When the observer-based stressor level was high the association was inverse; this might be

  4. Task-based evaluation of a 4D MAP-RBI-EM image reconstruction method for gated myocardial perfusion SPECT using a human observer study

    NASA Astrophysics Data System (ADS)

    Lee, Taek-Soo; Higuchi, Takahiro; Lautamäki, Riikka; Bengel, Frank M.; Tsui, Benjamin M. W.

    2015-09-01

    We evaluated the performance of a new 4D image reconstruction method for improved 4D gated myocardial perfusion (MP) SPECT using a task-based human observer study. We used a realistic 4D NURBS-based Cardiac-Torso (NCAT) phantom that models cardiac beating motion. Half of the population was normal; the other half had a regional hypokinetic wall motion abnormality. Noise-free and noisy projection data with 16 gates/cardiac cycle were generated using an analytical projector that included the effects of attenuation, collimator-detector response, and scatter (ADS), and were reconstructed using the 3D FBP without and 3D OS-EM with ADS corrections followed by different cut-off frequencies of a 4D linear post-filter. A 4D iterative maximum a posteriori rescaled-block (MAP-RBI)-EM image reconstruction method with ADS corrections was also used to reconstruct the projection data using various values of the weighting factor for its prior. The trade-offs between bias and noise were represented by the normalized mean squared error (NMSE) and averaged normalized standard deviation (NSDav), respectively. They were used to select reasonable ranges of the reconstructed images for use in a human observer study. The observers were trained with the simulated cine images and were instructed to rate their confidence on the absence or presence of a motion defect on a continuous scale. We then applied receiver operating characteristic (ROC) analysis and used the area under the ROC curve (AUC) index. The results showed that significant differences in detection performance among the different NMSE-NSDav combinations were found and the optimal trade-off from optimized reconstruction parameters corresponded to a maximum AUC value. The 4D MAP-RBI-EM with ADS correction, which had the best trade-off among the tested reconstruction methods, also had the highest AUC value, resulting in significantly better human observer detection performance when detecting regional myocardial wall motion

  5. Task-based evaluation of a 4D MAP-RBI-EM image reconstruction method for gated myocardial perfusion SPECT using a human observer study.

    PubMed

    Lee, Taek-Soo; Higuchi, Takahiro; Lautamäki, Riikka; Bengel, Frank M; Tsui, Benjamin M W

    2015-09-01

    We evaluated the performance of a new 4D image reconstruction method for improved 4D gated myocardial perfusion (MP) SPECT using a task-based human observer study. We used a realistic 4D NURBS-based Cardiac-Torso (NCAT) phantom that models cardiac beating motion. Half of the population was normal; the other half had a regional hypokinetic wall motion abnormality. Noise-free and noisy projection data with 16 gates/cardiac cycle were generated using an analytical projector that included the effects of attenuation, collimator-detector response, and scatter (ADS), and were reconstructed using the 3D FBP without and 3D OS-EM with ADS corrections followed by different cut-off frequencies of a 4D linear post-filter. A 4D iterative maximum a posteriori rescaled-block (MAP-RBI)-EM image reconstruction method with ADS corrections was also used to reconstruct the projection data using various values of the weighting factor for its prior. The trade-offs between bias and noise were represented by the normalized mean squared error (NMSE) and averaged normalized standard deviation (NSDav), respectively. They were used to select reasonable ranges of the reconstructed images for use in a human observer study. The observers were trained with the simulated cine images and were instructed to rate their confidence on the absence or presence of a motion defect on a continuous scale. We then applied receiver operating characteristic (ROC) analysis and used the area under the ROC curve (AUC) index. The results showed that significant differences in detection performance among the different NMSE-NSDav combinations were found and the optimal trade-off from optimized reconstruction parameters corresponded to a maximum AUC value. The 4D MAP-RBI-EM with ADS correction, which had the best trade-off among the tested reconstruction methods, also had the highest AUC value, resulting in significantly better human observer detection performance when detecting regional myocardial wall motion

  6. Task-Based Evaluation of a 4D MAP-RBI-EM Image Reconstruction Method for Gated Myocardial Perfusion SPECT using a Human Observer Study

    PubMed Central

    Lee, Taek-Soo; Higuchi, Takahiro; Lautamäki, Riikka; Bengel, Frank M.; Tsui, Benjamin M. W.

    2015-01-01

    We evaluated the performance of a new 4D image reconstruction method for improved 4D gated myocardial perfusion (MP) SPECT using a task-based human observer study. We used a realistic 4D NURBS-based Cardiac-Torso (NCAT) phantom that models cardiac beating motion. Half of the population was normal; the other half had a regional hypokinetic wall motion abnormality. Noise-free and noisy projection data with 16 gates/cardiac cycle were generated using an analytical projector that included the effects of attenuation, collimator-detector response, and scatter (ADS), and were reconstructed using the 3D FBP without and 3D OS-EM with ADS corrections followed by different cut-off frequencies of a 4D linear post-filter. A 4D iterative maximum a posteriori rescaled-block (MAP-RBI)-EM image reconstruction method with ADS corrections was also used to reconstruct the projection data using various values of the weighting factor for its prior. The trade-offs between bias and noise were represented by the normalized mean squared error (NMSE) and averaged normalized standard deviation (NSDav), respectively. They were used to select reasonable ranges of the reconstructed images for use in a human observer study. The observers were trained with the simulated cine images and were instructed to rate their confidence on the absence or presence of a motion defect on a continuous scale. We then applied receiver operating characteristic (ROC) analysis and used the area under the ROC curve (AUC) index. The results showed that significant differences in detection performance among the different NMSE-NSDav combinations were found and the optimal trade-off from optimized reconstruction parameters corresponded to a maximum AUC value. The 4D MAP-RBI-EM with ADS correction, which had the best trade-off among the tested reconstruction methods, also had the highest AUC value, resulting in significantly better human observer detection performance when detecting regional myocardial wall motion

  7. 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

    PubMed Central

    Thompson, J. D.; Chakraborty, D. P.; Szczepura, K.; Tootell, A. K.; Vamvakas, I.; Manning, D. J.; Hogg, P.

    2016-01-01

    Purpose: To evaluate nodule detection in an anthropomorphic chest phantom in computed tomography (CT) images reconstructed with adaptive iterative dose reduction 3D (AIDR3D) 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 to 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 AIDR3D 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 (AIDR3D 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 AIDR3D 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 multiple pairs of mAs settings

  8. Ensemble transform sensitivity method for adaptive observations

    NASA Astrophysics Data System (ADS)

    Zhang, Yu; Xie, Yuanfu; Wang, Hongli; Chen, Dehui; Toth, Zoltan

    2016-01-01

    The Ensemble Transform (ET) method has been shown to be useful in providing guidance for adaptive observation deployment. It predicts forecast error variance reduction for each possible deployment using its corresponding transformation matrix in an ensemble subspace. In this paper, a new ET-based sensitivity (ETS) method, which calculates the gradient of forecast error variance reduction in terms of analysis error variance reduction, is proposed to specify regions for possible adaptive observations. ETS is a first order approximation of the ET; it requires just one calculation of a transformation matrix, increasing computational efficiency (60%-80% reduction in computational cost). An explicit mathematical formulation of the ETS gradient is derived and described. Both the ET and ETS methods are applied to the Hurricane Irene (2011) case and a heavy rainfall case for comparison. The numerical results imply that the sensitive areas estimated by the ETS and ET are similar. However, ETS is much more efficient, particularly when the resolution is higher and the number of ensemble members is larger.

  9. Countesthorpe College: an observant study

    ERIC Educational Resources Information Center

    Riley, Ann; Stamatabis, Kathy

    1974-01-01

    Discussed the objectives and the conditions which made possible a new school embodying radical innovations. The results of a observational study at an early stage of the school's development, undertaken by a group of students, are summarised here by two of them, both now teaching in Leicestershire Upper Schools. (Editor/RK)

  10. 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 Central

    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

    2016-01-01

    Introduction 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. Methods and analyses 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. Ethics and dissemination 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

  11. 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.

  12. Observational Study of Travelers' Diarrhea.

    PubMed

    Meuris

    1995-03-01

    Background: European air travelers returning from Algeria, Egypt, Mexico, Morocco, and Tunisia were interviewed about their experience of travelers' diseases upon arrival in Brussels. Diarrhea was mentioned by 37% of the adults and 27% of the children. These subjects were questioned about the types of measures taken, type and duration of drug treatment (if any), and about duration of diarrhea and side effects experienced. Methods: Final analysis was performed based on 2160 interviews. The largest proportion of diarrhea was reported in the age group 15-24 years (46%). Results: The majority of the 2160 subjects had opted for drug treatment (81%): 927 subjects for loperamide alone, 235 for loperamide in combination with nifuroxazide, and 178 for nifuroxazide alone. Other drugs had been used less frequently. The median time to recovery was 2.4 days with loperamide compared to 3.2 days with nifuroxazide and to 3.4 days for the no-treatment group. Conclusions: A stratification of the results by severity of the diarrhea suggests a rank of antidiarrheal potency as follows: loperamide > nifuroxazide > no-drug treatment. The side effect with the highest incidence was constipation (2.4% with loperamide). (J Travel Med 2:11-15, 1995) Travelers' diarrhea is usually defined as the passage of at least three unformed stools per day or any number of such stools when accompanied by fever, abdominal cramping, or vomiting. The definition may be broadened to include more trivial bowel disturbance.1,2 The duration of this self-limited disease generally is 3 to 5 days. Medical intervention aims at shortening the duration of disease, thus allowing the sufferer to resume his or her usual activities at an early stage. A shortened period of recovery to physical well-being has obvious favorable economic implications if the traveler is on business and may help the maintenance of a desired level of quality of life while a traveler is on holiday. An observational study of various medical

  13. PM 2.5 characterization for time series studies: Organic molecular marker speciation methods and observations from daily measurements in Denver

    NASA Astrophysics Data System (ADS)

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

    Particulate matter less than 2.5 microns in diameter (PM 2.5) 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. PM 2.5 originates from multiple primary sources and is also formed through secondary processes in the atmosphere. It is plausible that some sources form PM 2.5 that is more toxic than PM 2.5 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 PM 2.5 source apportionment and health study. The first step in apportioning the PM 2.5 to different sources is to determine the chemical make-up of the PM 2.5. This paper presents the methodology used during the DASH study for organic speciation of PM 2.5. 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.

  14. 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

  15. Spatial Mapping as a Method for Observing Classroom Art Instruction.

    ERIC Educational Resources Information Center

    Susi, Frank D.

    1985-01-01

    Spatial mapping is a category system for directly observing instruction in art classrooms. A rationale for studying the spatial dimensions of teaching is presented, how to train observers is explained, procedures involved in a mapping episode are described, methods for analyzing data are suggested, and examples of instruments are presented.…

  16. 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.

  17. Evaluation of internal noise methods for Hotelling observer models

    SciTech Connect

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

    2007-08-15

    The inclusion of internal noise in model observers is a common method to allow for quantitative comparisons between human and model observer performance in visual detection tasks. In this article, we studied two different strategies for inserting internal noise into Hotelling model observers. In the first strategy, internal noise was added to the output of individual channels: (a) Independent nonuniform channel noise, (b) independent uniform channel noise. In the second strategy, internal noise was added to the decision variable arising from the combination of channel responses. The standard deviation of the zero mean internal noise was either constant or proportional to: (a) the decision variable's standard deviation due to the external noise, (b) the decision variable's variance caused by the external noise, (c) the decision variable magnitude on a trial to trial basis. We tested three model observers: square window Hotelling observer (HO), channelized Hotelling observer (CHO), and Laguerre-Gauss Hotelling observer (LGHO) using a four alternative forced choice (4AFC) signal known exactly but variable task with a simulated signal embedded in real x-ray coronary angiogram backgrounds. The results showed that the internal noise method that led to the best prediction of human performance differed across the studied model observers. The CHO model best predicted human observer performance with the channel internal noise. The HO and LGHO best predicted human observer performance with the decision variable internal noise. The present results might guide researchers with the choice of methods to include internal noise into Hotelling model observers when evaluating and optimizing medical image quality.

  18. The performance of different propensity-score methods for estimating differences in proportions (risk differences or absolute risk reductions) in observational studies.

    PubMed

    Austin, Peter C

    2010-09-10

    Propensity score methods are increasingly being used to estimate the effects of treatments on health outcomes using observational data. There are four methods for using the propensity score to estimate treatment effects: covariate adjustment using the propensity score, stratification on the propensity score, propensity-score matching, and inverse probability of treatment weighting (IPTW) using the propensity score. When outcomes are binary, the effect of treatment on the outcome can be described using odds ratios, relative risks, risk differences, or the number needed to treat. Several clinical commentators suggested that risk differences and numbers needed to treat are more meaningful for clinical decision making than are odds ratios or relative risks. However, there is a paucity of information about the relative performance of the different propensity-score methods for estimating risk differences. We conducted a series of Monte Carlo simulations to examine this issue. We examined bias, variance estimation, coverage of confidence intervals, mean-squared error (MSE), and type I error rates. A doubly robust version of IPTW had superior performance compared with the other propensity-score methods. It resulted in unbiased estimation of risk differences, treatment effects with the lowest standard errors, confidence intervals with the correct coverage rates, and correct type I error rates. Stratification, matching on the propensity score, and covariate adjustment using the propensity score resulted in minor to modest bias in estimating risk differences. Estimators based on IPTW had lower MSE compared with other propensity-score methods. Differences between IPTW and propensity-score matching may reflect that these two methods estimate the average treatment effect and the average treatment effect for the treated, respectively.

  19. Methods of observation of the centrifugal quantum states of neutrons

    NASA Astrophysics Data System (ADS)

    Cubitt, R.; Nesvizhevsky, V. V.; Petukhov, A. K.; Voronin, A. Yu.; Pignol, G.; Protasov, K. V.; Gurshijants, P.

    2009-12-01

    We propose methods for observation of the quasi-stationary states of neutrons, localized near a curved mirror surface. The bounding effective well is formed by the centrifugal potential and the mirror's optical potential. This phenomenon is an example of an exactly solvable "quantum bouncer" problem that can be studied experimentally. It could provide a new tool for studying fundamental neutron-matter interactions, neutron quantum optics and surface physics effects. The feasibility of observation of such quantum states has been proven in first experiments.

  20. 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

  1. A Comparison of Methods for Ocean Reconstruction from Sparse Observations

    NASA Astrophysics Data System (ADS)

    Streletz, G. J.; Kronenberger, M.; Weber, C.; Gebbie, G.; Hagen, H.; Garth, C.; Hamann, B.; Kreylos, O.; Kellogg, L. H.; Spero, H. J.

    2014-12-01

    We present a comparison of two methods for developing reconstructions of oceanic scalar property fields from sparse scattered observations. Observed data from deep sea core samples provide valuable information regarding the properties of oceans in the past. However, because the locations of sample sites are distributed on the ocean floor in a sparse and irregular manner, developing a global ocean reconstruction is a difficult task. Our methods include a flow-based and a moving least squares -based approximation method. The flow-based method augments the process of interpolating or approximating scattered scalar data by incorporating known flow information. The scheme exploits this additional knowledge to define a non-Euclidean distance measure between points in the spatial domain. This distance measure is used to create a reconstruction of the desired scalar field on the spatial domain. The resulting reconstruction thus incorporates information from both the scattered samples and the known flow field. The second method does not assume a known flow field, but rather works solely with the observed scattered samples. It is based on a modification of the moving least squares approach, a weighted least squares approximation method that blends local approximations into a global result. The modifications target the selection of data used for these local approximations and the construction of the weighting function. The definition of distance used in the weighting function is crucial for this method, so we use a machine learning approach to determine a set of near-optimal parameters for the weighting. We have implemented both of the reconstruction methods and have tested them using several sparse oceanographic datasets. Based upon these studies, we discuss the advantages and disadvantages of each method and suggest possible ways to combine aspects of both methods in order to achieve an overall high-quality reconstruction.

  2. The home observation assessment method (HOAM): real-time naturalistic observation of families in their homes.

    PubMed

    Steinglass, P

    1979-09-01

    The Home Observation Assessment Method (HOAM) is a new method developed to carry out objective coding of family interaction over extended time periods in a home setting. It is a computer-compatible coding system that permits on-line data reduction of interactional variables emphasizing contextual and structural dimensions of family behavior. To date, the HOAM has been applied to the study of 31 families observed for a total of over 250 sessions. Initial analysis of data from these sessions indicates that coder reliability is high and that the HOAM successfully measures dimensions of family behavior independent of architectural aspects of the home setting. Preliminary findings also indicate that although families differ dramatically along the interactional dimensions measured by the HOAM, all families studied spent remarkably little time in decision-making behavior, suggesting that behavior in the home is predominantly "maintenance-oriented."

  3. 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…

  4. A new method for astrometric observations of asteroids

    NASA Technical Reports Server (NTRS)

    Pauwels, Thierry

    1992-01-01

    In this paper we propose a new method for photographic astrometric observations of asteroids. We discuss its advantages and disadvantages and compare them to the advantages and disadvantages of the classical photographic methods. The new method is best suited for observations on a spot where no CCD cameras, blink or stereo comparators are available and when a fast detection of unknown objects is required.

  5. An Observational Assessment Method for Aging Laboratory Rats

    PubMed Central

    Phillips, Pamela M; Jarema, Kimberly A; Kurtz, David M; MacPhail, Robert C

    2010-01-01

    The rapid growth of the aging human population highlights the need for laboratory animal models to study the basic biologic processes of aging and susceptibility to disease, drugs, and environmental pollutants. Methods are needed to evaluate the health of aging animals over time, particularly methods for efficiently monitoring large research colonies. Here we describe an observational assessment method that scores appearance, posture, mobility, and muscle tone on a 5-point scale that can be completed in about 1 min. A score of 1 indicates no deterioration, whereas a score of 5 indicates severe deterioration. Tests were applied to male Brown Norway rats between 12 and 36 mo of age (n = 32). The rats were participating concurrently in experiments on the behavioral effects of intermittent exposure (approximately every 4 mo) to short-acting environmental chemicals. Results demonstrated that aging-related signs of deterioration did not appear before 18 mo of age. Assessment scores and variability then increased with age. Body weights increased until approximately 24 mo, then remained stable, but decreased after 31 mo for the few remaining rats. The incidence of death increased slightly from 20 to 28 mo of age and then rose sharply; median survival age was approximately 30 mo, with a maximum of 36 mo. The results indicate that our observational assessment method supports efficient monitoring of the health of aging rats and may be useful in studies on susceptibility to diseases, drugs, and toxicants during old age. PMID:21205442

  6. Earth Observing System: Global Observations to Study the Earth's Environment

    NASA Technical Reports Server (NTRS)

    King, Michael D.

    2003-01-01

    The Earth Observing System (EOS) is a space-based observing system comprised of a series of satellite sensors by which scientists can monitor the Earth, a Data and Information System (EOSDIS) enabling researchers worldwide to access the satellite data, and an interdisciplinary science research program to interpret the satellite data. During the last couple of years, four EOS science missions were launched, representing observations of (i) total solar irradiance, (ii) Earth radiation budget, (iii) land cover & land use change, (iv) ocean processes (vector wind, sea surface temperature, and ocean color), (v) atmospheric processes (aerosol and cloud properties, water vapor, and temperature and moisture profiles), and (vi) tropospheric chemistry. In succeeding years many more satellites will be launched that will contribute immeasurably to our understanding of the Earth's environment. In this presentation I will describe how scientists are using NASA's Earth science data to examine land use and natural hazards, environmental air quality, including: dust storms over the worlds deserts, cloud and radiation properties, sea surface temperature, and winds over the ocean, with a special emphasis on satellite observations available for studying the southern African environment.

  7. 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. PMID:26817867

  8. Methods for observational post-licensure medical product safety surveillance.

    PubMed

    Nelson, Jennifer C; Cook, Andrea J; Yu, Onchee; Zhao, Shanshan; Jackson, Lisa A; Psaty, Bruce M

    2015-04-01

    Post-licensure medical product safety surveillance is important for detecting adverse events potentially not identified pre-licensure. Historically, post-licensure safety monitoring has been accomplished using passive reporting systems and by conducting formal Phase IV randomized trials or large epidemiological studies, also known as safety surveillance or pharmacovigilance studies. However, crucial gaps in the safety evidence base provided by these approaches have led to high profile product withdrawals and growing public concern about unknown health risks associated with licensed products. To address the limitations of existing surveillance systems and to facilitate more accurate and rapid detection of safety problems, new systems involving active surveillance of large, population-based cohorts using observational health care databases are being developed. In this article, we review common statistical methods that have been employed previously for post-licensure safety monitoring, including data mining and sequential hypothesis testing, and assess which methods may be promising for potential use within this newly proposed prospective observational cohort monitoring framework. We discuss gaps in existing approaches and identify areas where methodological development is needed to improve the success of safety surveillance efforts in this setting.

  9. Can we observe changes in mRNA “state”? Overview of methods to study mRNA interactions with regulatory proteins relevant in cancer related processes

    PubMed Central

    Zurla, C.; Jung, J.; Santangelo, P. J.

    2015-01-01

    RNA binding proteins (RBP) regulate the editing, localization, stabilization, translation, and degradation of ribonucleic acids (RNA) through their interactions with specific cis-acting elements within target RNAs. Post-transcriptional regulatory mechanisms are directly involved in the control of the immune response and stress response and their alterations play a crucial role in cancer related processes. In this review, we discuss mRNAs and RNA binding proteins relevant to tumorigenesis, current methodologies for detecting RNA interactions, and last, we describe a novel method to detect such interactions, which combines peptide modified, RNA imaging probes (FMTRIPs) with proximity ligation (PLA) and rolling circle amplification (RCA). This assay detects native RNA in a sequence specific and single RNA sensitive manner, and PLA allows for the quantification and localization of protein–mRNA interactions with single-interaction sensitivity in situ. PMID:26605378

  10. Qualitative research: Observational methods in health care settings.

    PubMed Central

    Mays, N.; Pope, C.

    1995-01-01

    Clinicians used to observing individual patients, and epidemiologists trained to observe the course of disease, may be forgiven for misunderstanding the term observational method as used in qualitative research. In contrast to the clinician or epidemiologist, the qualitative researcher systematically watches people and events to find out about behaviours and interactions in natural settings. Observation, in this sense, epitomises the idea of the researcher as the research instrument. It involves "going into the field"--describing and analysing what has been seen. In health care settings this method has been insightful and illuminating, but it is not without pitfalls for the unprepared researcher. Images p183-a PMID:7613435

  11. Methods for studying oogenesis

    PubMed Central

    Hudson, Andrew M.; Cooley, Lynn

    2014-01-01

    Drosophila oogenesis is an excellent system for the study of developmental cell biology. Active areas of research include stem cell maintenance, gamete development, pattern formation, cytoskeletal regulation, intercellular communication, intercellular transport, cell polarity, cell migration, cell death, morphogenesis, cell cycle control, and many more. The large size and relatively simple organization of egg chambers make them ideally suited for microscopy of both living and fixed whole mount tissue. A wide range of tools is available for oogenesis research. Newly available shRNA transgenic lines provide an alternative to classic loss-of-function F2 screens and clonal screens. Gene expression can be specifically controlled in either germline or somatic cells using the Gal4/UAS system. Protein trap lines provide fluorescent tags of proteins expressed at endogenous levels for live imaging and screening backgrounds. This review provides information on many available reagents and key methods for research in oogenesis. PMID:24440745

  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. 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.

  14. 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".

  15. 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.

  16. Observation of near earth asteroids with using of combined method

    NASA Astrophysics Data System (ADS)

    Sybiryakova, Yevgeniya; Shulga, Alexandr; Vovk, Vasyl; Kulichenko, Mykola

    2016-07-01

    Observation of many near earth asteroids (NEAs) especially small diameters (less than 140m) are possible only during close approach with Earth when their magnitude and apparent motion increasing. The combined method of observation is used in RI NAO for observation of NEAs with high apparent motion. Combined method consists in separation of processes of observation of reference stars and NEA and using of the short time delay and integration mode (TDI). The main condition of TDI mode using is the fixing the column of CCD in the direction of NEA motion, for this goal the special device camera rotator was developed and applied. Camera rotator rotates the CCD camera around the optical axis of lens. All observations in RI NAO were carried out with using of KT-50 telescope (D=0.5m, F=3.0m). The telescope equipped with CCD-camera Apogee Alta U9000 (3k×3k) and camera rotator. Field of view of the telescope is 0.7°×0.7°. Limiting magnitude is 18.5. Since 2008, 5300 positions of 325 NEAs have been obtained on KT-50 telescope. RI NAO has an experience in the follow-up NEA observation and small size and low elongation (with solar elongation less then 45°) NEA observation. (O-C) of position are within ±1˝.

  17. What health care managers do: applying Mintzberg's structured observation method.

    PubMed

    Arman, Rebecka; Dellve, Lotta; Wikström, Ewa; Törnström, Linda

    2009-09-01

    Aim The aim of the present study was to explore and describe what characterizes first- and second-line health care managers' use of time. Background Many Swedish health care managers experience difficulties managing their time. Methods Structured and unstructured observations were used. Ten first- and second-line managers in different health care settings were studied in detail from 3.5 and 4 days each. Duration and frequency of different types of work activities were analysed. Results The individual variation was considerable. The managers' days consisted to a large degree of short activities (<9 minutes). On average, nearly half of the managers' time was spent in meetings. Most of the managers' time was spent with subordinates and <1% was spent alone with their superiors. Sixteen per cent of their time was spent on administration and only a small fraction on explicit strategic work. Conclusions The individual variations in time use patterns suggest the possibility of interventions to support changes in time use patterns. Implications for nursing management A reliable description of what managers do paves the way for analyses of what they should do to be effective.

  18. Earth Observing System: Global Observations to Study the Earth's Environment

    NASA Technical Reports Server (NTRS)

    King, Michael D.

    2001-01-01

    The Earth Observing System (EOS) is a space-based observing system comprised of a series of satellite sensors by which scientists can monitor the Earth, a Data and Information System (EOSDIS) enabling researchers worldwide to access the satellite data, and an interdisciplinary science research program to interpret the satellite data. During the last couple of years, four EOS science missions were launched, representing observations of (1) total solar irradiance, (2) Earth radiation budget, (3) land cover & land use change, (4) ocean processes (vector wind, sea surface temperature, and ocean color), (5) atmospheric processes (aerosol and cloud properties, water vapor, and temperature and moisture profiles), and (6) tropospheric chemistry. In succeeding years many more satellites will be launched that will contribute immeasurably to our understanding of the Earth's environment. In this presentation I will describe how scientists are using NASA's Earth science data to examine land use and natural hazards, environmental air quality, including dust storms over the world's deserts, cloud and radiation properties, sea surface temperature, and winds over the ocean.

  19. Observer ratings of neighborhoods: comparison of two methods

    PubMed Central

    2013-01-01

    Background Although neighborhood characteristics have important relationships with health outcomes, direct observation involves imperfect measurement. The African American Health (AAH) study included two observer neighborhood rating systems (5-item Krause and 18-item AAH Neighborhood Assessment Scale [NAS]), initially fielded at two different waves. Good measurement characteristics were previously shown for both, but there was more rater variability than desired. In 2010 both measures were re-fielded together, with enhanced training and field methods implemented to decrease rater variability while maintaining psychometric properties. Methods AAH included a poor inner city and more heterogeneous suburban areas. Four interviewers rated 483 blocks, with 120 randomly-selected blocks rated by two interviewers. We conducted confirmatory factor analysis of scales and tested the Krause (5-20 points), AAH 18-item NAS (0-28 points), and a previous 7-item and new 5-item versions of the NAS (0-17 points, 0-11 points). Retest reliability for items (kappa) and scales (Intraclass Correlation Coefficient [ICC]) were calculated overall and among pre-specified subgroups. Linear regression assessed interviewer effects on total scale scores and assessed concurrent validity on lung and lower body functions. Mismeasurement effects on self-rated health were also assessed. Results Scale scores were better in the suburbs than in the inner city. ICC was poor for the Krause scale (ICC=0.19), but improved if the retests occurred within 10 days (ICC=0.49). The 7- and 5-item NAS scales had better ICCs (0.56 and 0.62, respectively), and were higher (0.71 and 0.73) within 10 days. Rater variability for the Kraus and 5- and 7-item NAS scales was 1-3 points (compared to the supervising rater). Concurrent validity was modest, with residents living in worse neighborhood conditions having worse function. Unadjusted estimates were biased towards the null compared with measurement-error corrected

  20. Observations on variational and projector Monte Carlo methods.

    PubMed

    Umrigar, C J

    2015-10-28

    Variational Monte Carlo and various projector Monte Carlo (PMC) methods are presented in a unified manner. Similarities and differences between the methods and choices made in designing the methods are discussed. Both methods where the Monte Carlo walk is performed in a discrete space and methods where it is performed in a continuous space are considered. It is pointed out that the usual prescription for importance sampling may not be advantageous depending on the particular quantum Monte Carlo method used and the observables of interest, so alternate prescriptions are presented. The nature of the sign problem is discussed for various versions of PMC methods. A prescription for an exact PMC method in real space, i.e., a method that does not make a fixed-node or similar approximation and does not have a finite basis error, is presented. This method is likely to be practical for systems with a small number of electrons. Approximate PMC methods that are applicable to larger systems and go beyond the fixed-node approximation are also discussed. PMID:26520496

  1. Observations on variational and projector Monte Carlo methods

    NASA Astrophysics Data System (ADS)

    Umrigar, C. J.

    2015-10-01

    Variational Monte Carlo and various projector Monte Carlo (PMC) methods are presented in a unified manner. Similarities and differences between the methods and choices made in designing the methods are discussed. Both methods where the Monte Carlo walk is performed in a discrete space and methods where it is performed in a continuous space are considered. It is pointed out that the usual prescription for importance sampling may not be advantageous depending on the particular quantum Monte Carlo method used and the observables of interest, so alternate prescriptions are presented. The nature of the sign problem is discussed for various versions of PMC methods. A prescription for an exact PMC method in real space, i.e., a method that does not make a fixed-node or similar approximation and does not have a finite basis error, is presented. This method is likely to be practical for systems with a small number of electrons. Approximate PMC methods that are applicable to larger systems and go beyond the fixed-node approximation are also discussed.

  2. Observations on variational and projector Monte Carlo methods

    SciTech Connect

    Umrigar, C. J.

    2015-10-28

    Variational Monte Carlo and various projector Monte Carlo (PMC) methods are presented in a unified manner. Similarities and differences between the methods and choices made in designing the methods are discussed. Both methods where the Monte Carlo walk is performed in a discrete space and methods where it is performed in a continuous space are considered. It is pointed out that the usual prescription for importance sampling may not be advantageous depending on the particular quantum Monte Carlo method used and the observables of interest, so alternate prescriptions are presented. The nature of the sign problem is discussed for various versions of PMC methods. A prescription for an exact PMC method in real space, i.e., a method that does not make a fixed-node or similar approximation and does not have a finite basis error, is presented. This method is likely to be practical for systems with a small number of electrons. Approximate PMC methods that are applicable to larger systems and go beyond the fixed-node approximation are also discussed.

  3. 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…

  4. Method for observing phase objects without halos or directional shadows.

    PubMed

    Suzuki, Yoshimasa; Kajitani, Kazuo; Ohde, Hisashi

    2015-03-01

    A new microscopy method for observing phase objects without halos or directional shadows is proposed. The method is based on transformation of the surface profile of phase objects into a light intensity pattern. The key optical element is an annular aperture at the front focal plane of a condenser. 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. Theory and experimental results are presented. Phase images of induced pluripotent stem (iPS) cells with clear outlines were obtained with this method.

  5. Testing Fractal Methods on Observed and Simulated Solar Magnetograms

    NASA Technical Reports Server (NTRS)

    Adams, M.; Falconer, D. A.; Lee, J. K.; Jones, C.

    2003-01-01

    The term "magnetic complexity" has not been sufficiently quantified. To accomplish this, we must understand the relationship between the observed magnetic field of solar active regions and fractal dimension measurements. Using data from the Marshall Space Flight Center's vector magnetograph ranging from December 1991 to July 2001, we compare the results of several methods of calculating a fractal dimension, e.g., Hurst coefficient, the Higuchi method, power spectrum, and 2-D Wavelet Packet Analysis. In addition, we apply these methods to synthetic data, beginning with representations of very simple dipole regions, ending with regions that are magnetically complex.

  6. 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.

  7. 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…

  8. Mobile vehicle road and weather observation quality check methods

    NASA Astrophysics Data System (ADS)

    Koller, Daniel Raymond

    Today State Departments of Transportation rely more and more on road weather data to make maintenance decisions. Inaccurate data can result in wrong treatment applications or inadequate staffing levels to maintain the roadway at the desired level of service. Previous methods of road condition data reporting have been limited to static in situ sensor stations. These road weather information systems (RWIS) provide varied data about precipitation, winds, temperature, and more, but their siting does not always provide an accurate representation of weather and road conditions along the roadway. The use of mobile data collection from vehicles travelling the highway corridors may assist in the locations where RWIS sitings are sparse or non-existent. The United States Department of Transporation's "Connected Vehicle" (formally IntelliDrive) research project is designed to create a fully connected transportation system providing road and weather data collection from an extensive array of vehicles. While the implementation of Connected Vehicle is in the future, some of the theories and technologies are already in place today. Several states, as a part of the Pooled Fund Study Maintenance Decision Support System (MDSS), have equipped their winter maintenance vehicles with Mobile Data Collection Automated / Vehicle Location (MDC/AVL) systems. In addition, since 1996, automobiles sold in the United States are required to be equipped with an Onboard Diagnostic Version 2 (OBDII) port that streams live data from sensors located in and around the vehicle. While these sensors were designed for vehicle diagnostics, some of the data can be used to determine weather characteristics around the vehicle. The OBDII data can be collected by a smartphone and sent to a server in real time to be processed. These mobile systems may fill the information gap along the roads that stationary environmental sensor stations are not able to collect. Particular concern and care needs to be focused on

  9. Displacement Monitoring and Sensitivity Analysis in the Observational Method

    NASA Astrophysics Data System (ADS)

    Górska, Karolina; Muszyński, Zbigniew; Rybak, Jarosław

    2013-09-01

    This work discusses the fundamentals of designing deep excavation support by means of observational method. The effective tools for optimum designing with the use of the observational method are both inclinometric and geodetic monitoring, which provide data for the systematically updated calibration of the numerical computational model. The analysis included methods for selecting data for the design (by choosing the basic random variables), as well as methods for an on-going verification of the results of numeric calculations (e.g., MES) by way of measuring the structure displacement using geodetic and inclinometric techniques. The presented example shows the sensitivity analysis of the calculation model for a cantilever wall in non-cohesive soil; that analysis makes it possible to select the data to be later subject to calibration. The paper presents the results of measurements of a sheet pile wall displacement, carried out by means of inclinometric method and, simultaneously, two geodetic methods, successively with the deepening of the excavation. This work includes also critical comments regarding the usefulness of the obtained data, as well as practical aspects of taking measurement in the conditions of on-going construction works.

  10. 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.; Sullivan, John T.; Langford, Andrew O.; Senff, Christoph J.; Alvarez, Raul; Eloranta, Edwin

    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.

  11. 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...

  12. Empirical methods of reducing the observations in geodetic networks

    NASA Astrophysics Data System (ADS)

    Kadaj, Roman

    2016-06-01

    The paper presents empirical methodology of reducing various kinds of observations in geodetic network. A special case of reducing the observation concerns cartographic mapping. For numerical illustration and comparison of methods an application of the conformal Gauss-Krüger mapping was used. Empirical methods are an alternative to the classic differential and multi-stages methods. Numerical benefits concern in particular very long geodesics, created for example by GNSS vectors. In conventional methods the numerical errors of reduction values are significantly dependent on the length of the geodesic. The proposed empirical methods do not have this unfavorable characteristics. Reduction value is determined as a difference (or especially scaled difference) of the corresponding measures of geometric elements (distances, angles), wherein these measures are approximated independently in two spaces based on the known and corresponding approximate coordinates of the network points. Since in the iterative process of the network adjustment, coordinates of the points are systematically improved, approximated reductions also converge to certain optimal values.

  13. 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.

  14. USGEO National Earth Observation Assessment Methods for Evaluating the Relative Contributions of Earth Observing Systems to Societal Benefit

    NASA Astrophysics Data System (ADS)

    Gallo, J.; Stryker, T.

    2015-12-01

    The second National Civil Earth Observation Assessment identifies the inputs and relative contributions of the portfolio of observing systems currently relied upon by Federal agencies to meet key Earth observing objectives. The Assessment employs a hierarchical value-tree framework that traces the pathways through which Earth observing systems contribute value across 13 societal benefit areas, utilizing multiple levels to provide logical traceability. This presentation describes the methods used to construct societal benefit area value-trees that include key objectives and the information products, services, and research derived from Earth observations that help satisfy them. It describes the methods for weighting nodes at multiple levels of each value-tree and the expert elicitation process for assessing the relative contributions of Earth observing systems to the development of information products, services, and research. The methodology employed in the Assessment is especially useful at assessing the interdependence and relative contributions of multiple Earth observing systems on the development of blended information products and tracing information pathways from direct observations through intermediate products, such as models, to end-products used to improve decision-making. This presentation will highlight case study examples from the 13 societal benefit areas (agriculture and forestry, biodiversity, climate, disasters, ecosystems, energy and mineral resources, human health, ocean and costal resources, space weather, transportation, water resources weather, and reference measurements) to demonstrate tractability from Earth observing systems, through information products and research that satisfy key objectives, to societal benefit.

  15. 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.

  16. 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…

  17. [The advantages and limitations of observational studies].

    PubMed

    Onder, Graziano

    2013-03-01

    Randomized clinical trials are considered the gold standard for establishing treatment efficacy and generate evidence-based medicine. Nonetheless, because of the stringent exclusion criteria used in selecting study populations, concerns are raised about the limited generalizability of evidence they provide. Indeed, randomized clinical trials assess treatment efficacy for an "average" patient, quite often far from older adults characterized by chronic comorbidities of different severity, or by functional and/or cognitive impairment. Observational studies have been proposed as alternative means of testing intervention effectiveness in older populations with multifaceted problems. Unlike randomized clinical trials, they assess outcomes in regular clinical practice, thereby reflecting real adherence to treatment/intervention. The availability of huge, high quality databases offers the potential to bring research closer to practice and audit. Databases provide fertile grounds for observational studies, and can generate hypotheses and provide ready access to trialists as well, setting new possibilities for epidemiological research. They must include complete data on all consecutive patients, use standard definitions of conditions and outcomes, and include all clinical characteristics likely to affect outcomes. In addition, their potential for research and audit is greatly enhanced by linking to other databases, like the census ones, which allow evaluation of geographical and contextual information.

  18. 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, C.; 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.

  19. 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…

  20. Reported Significant Observation (RSO) studies. Revision 1

    SciTech Connect

    Eicher, R.W.

    1992-12-01

    The Reported Significant Observation (RSO) study used in the field of safety is an information-gathering technique where employee-participants describe situations they have personally witnessed involving good and bad practices and safe and unsafe conditions. This information is useful in the risk assessment process because it focuses on hazards and thereby facilitates their elimination. However, RSO cannot be the only component in a risk assessment program. Used by the Air Force in their aviation psychology program and further developed by John C. Flanagan, RSO is more commonly known as the ``Critical Incident Technique.`` However, the words ``Critical`` and ``Incident`` had other connotations in nuclear safety, prompting early users within the Aerojet Nuclear Company to coin the more fitting title of ``Reported Significant Observations.`` The technique spread slowly in the safety field primarily because the majority of users were researchers interested in after-the-fact data, with application to everyday problems and behavioral factors. RSO was formally recognized as a significant hazard reduction tool during the development of the Management Oversight and Risk Tree (MORT) program for the US Atomic Energy Commission. The Department of Energy (DOE) has, in turn, adopted MORT for its system safety program, and this has resulted in RSO being a modern and viable technique for DOE contractor safety programs.

  1. The Effects of Integrating Technology, Observation and Writing into a Teacher Education Method Course

    ERIC Educational Resources Information Center

    Jang, Syh-Jong

    2008-01-01

    The purpose of this study was to integrate asynchronous learning technology with teaching strategies on observation and writing into a teacher education method course. The research questions were to explore the effects of the innovative teaching method and to compare it with the traditional teaching method. There were 134 preservice teachers…

  2. 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.

  3. Observational and Modeling Study of Mesopheric Bores

    NASA Astrophysics Data System (ADS)

    Loughmiller, P.; Hickey, M.; Franke, S.; Kelley, M.

    In mid-ladtitude studies of the dynamics of the mesosphere and lower thermosphere, some of the most intriguing phenomena observed high over the Hawaiian night skies are internal bores. These events affecting chemiluminescence are documented in monochromatic airglow images taken by high performance all-sky CCD imaging systems operating at the Maui Space Surveillance Site on top of Haleakala Crater. Data continues to be collected as part of the ongoing, collaborative Maui - Mesosphere and Lower Thermosphere (MALT) campaign, jointly sponsored by the National Science Foundation and the Air Force Office of Scientific Research. Bolstered by the Maui-MALT dataset, several theories now exist for mesospheric bores, agreeing in principle that they are likely nonlinear structures spawned by gravity waves and propagating within ducted waveguide regions. We investigate these plausible theories using a multi-instrument 2 approach, looking for correlation between bores and thermal inversion layers or wind shears, both potential guiding structures for lateral, geographic bore propagation.

  4. Observational and modelling study of mesospheric bores

    NASA Astrophysics Data System (ADS)

    Loughmiller, P. J.; Kelley, M. C.; Hickey, M. P.

    In studies of the dynamics of the upper atmosphere some of the most intriguing mesospheric phenomena observed high over the Hawaiian night skies are wall waves and internal bores These events are documented in airglow images taken by high performance all-sky CCD imaging systems operating on top of Haleakala Crater as part of the ongoing collaborative Maui - Mesosphere and Lower Thermosphere MALT campaign jointly sponsored by the National Science Foundation and the Air Force Office of Scientific Research Bolstered by the Maui-MALT dataset several theories now exist for mesospheric bores agreeing in principle that they are likely nonlinear structures spawned by gravity waves and propagating within a thermal inversion layer A new investigation will model optical emissions using a robust time-dependent chemical dynamics model to explore the airglow response to ducted gravity waves and in turn the geographical and vertical coupling relationships which may exist

  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. 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.

  7. BAYESIAN SHRINKAGE METHODS FOR PARTIALLY OBSERVED DATA WITH MANY PREDICTORS*

    PubMed Central

    Boonstra, Philip S.; Mukherjee, Bhramar; Taylor, Jeremy MG

    2013-01-01

    Motivated by the increasing use of and rapid changes in array technologies, we consider the prediction problem of fitting a linear regression relating a continuous outcome Y to a large number of covariates X, eg measurements from current, state-of-the-art technology. For most of the samples, only the outcome Y and surrogate covariates, W, are available. These surrogates may be data from prior studies using older technologies. Owing to the dimension of the problem and the large fraction of missing information, a critical issue is appropriate shrinkage of model parameters for an optimal bias-variance tradeoff. We discuss a variety of fully Bayesian and Empirical Bayes algorithms which account for uncertainty in the missing data and adaptively shrink parameter estimates for superior prediction. These methods are evaluated via a comprehensive simulation study. In addition, we apply our methods to a lung cancer dataset, predicting survival time (Y) using qRT-PCR (X) and microarray (W) measurements. PMID:24436727

  8. Observations from the CDX Nonlinear Sawtooth Study

    NASA Astrophysics Data System (ADS)

    Breslau, J.; Park, W.; Hudson, S.; Jardin, S.; Strauss, H.

    2006-04-01

    We present two separate sets of observations from modeling sawteeth in the CDX tokamak with the M3D code [1] as part of a cross-code benchmark. One is that, in addition to the internal kink, the starting equilibrium is linearly unstable to a range of high-n resistive ballooning-like modes [2], which can only be suppressed by the assumption of extremely high perpendicular heat transport. There is evidence that such transport is present in CDX itself, possibly induced by the edge modes [3], which would thereby saturate nonlinearly. Analysis of field line stochasticity as a mechanism for this saturation will be presented. The second topic is the finding that the sawtooth, though fundamentally a 1,1 mode, has considerable structure in the toroidal direction which is not easily resolved even with the retention of tens of mode numbers in the nonlinear run. The demands of a convergence study are therefore more stringent than might at first be supposed; implications for the development of predictive capability are discussed. [1] W. Park et al., Phys. Plasmas 6, 1796 (1999). [2] H.R. Strauss. Phys. Fluids 24, 2004 (1981). [3] B.A. Carreras and P.H. Diamond, Phys. Fluids B 1, 1011 (1989).

  9. Observational and Modeling Study of Mesopheric Bores

    NASA Astrophysics Data System (ADS)

    Loughmiller, P.; Kelley, M.; Hickey, M.

    In our studies of the dynamics of the upper atmosphere, some of the most intriguing mesospheric phenomena we observe high over the Hawaiian night skies are internal bores. These events affecting chemiluminescence are documented in monochromatic airglow images taken by high performance all-sky CCD imaging systems operating at the Maui Space Surveillance Site on top of Haleakala Crater. Data is collected as part of the ongoing, collaborative Maui - Mesosphere and Lower Thermosphere (MALT) campaign, jointly sponsored by the National Science Foundation and the Air Force Office of Scientific Research. Bolstered by the Maui-MALT dataset, several theories now exist for mesospheric bores, agreeing in principle that they are likely nonlinear structures spawned by gravity waves and propagating within ducted waveguide regions, such as thermal inversion layers. A new investigation will model optical emissions using a robust, time-dependent, chemical dynamics model to explore the airglow response to ducted gravity waves and, in turn, the geographical and vertical coupling relationships which may exist.

  10. Observational study of subclinical diabetic macular edema

    PubMed Central

    Bressler, N M; Miller, K M; Beck, R W; Bressler, S B; Glassman, A R; Kitchens, J W; Melia, M; Schlossman, D K

    2012-01-01

    Purpose To determine the rate of progression of eyes with subclinical diabetic macular edema (DME) to clinically apparent DME or DME necessitating treatment during a 2-year period. Methods In all, 43 eyes from 39 study participants with subclinical DME, defined as absence of foveal center edema as determined with slit lamp biomicroscopy but a center point thickness (CPT) between 225 and 299 μm on time domain (Stratus, Carl Zeiss Meditec) optical coherence tomography (OCT) scan, were enrolled from 891 eyes of 582 subjects screened. Eyes were evaluated annually for up to 2 years for the primary outcome, which was an increase in OCT CPT of at least 50 μm from baseline and a CPT of at least 300 μm, or treatment for DME (performed at the discretion of the investigator). Results The cumulative probability of meeting an increase in OCT CPT of at least 50 μm from baseline and a CPT of at least 300 μm, or treatment for DME was 27% (95% confidence interval (CI): 14%, 38%) by 1 year and 38% (95% CI: 23%, 50%) by 2 years. Conclusions Although subclinical DME may be uncommon, this study suggests that between approximately one-quarter and one-half of eyes with subclinical DME will progress to more definite thickening or be judged to need treatment for DME within 2 years after its identification. PMID:22441027

  11. 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.

  12. A processing method and results of meteor shower radar observations

    NASA Technical Reports Server (NTRS)

    Belkovich, O. I.; Suleimanov, N. I.; Tokhtasjev, V. S.

    1987-01-01

    Studies of meteor showers permit the solving of some principal problems of meteor astronomy: to obtain the structure of a stream in cross section and along its orbits; to retrace the evolution of particle orbits of the stream taking into account gravitational and nongravitational forces and to discover the orbital elements of its parent body; to find out the total mass of solid particles ejected from the parent body taking into account physical and chemical evolution of meteor bodies; and to use meteor streams as natural probes for investigation of the average characteristics of the meteor complex in the solar system. A simple and effective method of determining the flux density and mass exponent parameter was worked out. This method and its results are discussed.

  13. An observational study of the dryline

    SciTech Connect

    Ziegler, C.L. ); Hane, C.E. )

    1993-04-01

    This study Presents analyses of data collected in the vicinity of a cloud-free dryline that occurred in western, Oklahoma on 24 May 1989. Observations reveal sharp contrasts across the quasi-stationary, north-south dryline during midafternoon. Of greatest significance is a pronounced gradient of virtual potential temperature, although horizontal convergence and vorticity also maximize at the dryline. The environment of the 24 May dryline is dominated by vertical mixing that maintains a convective boundary layer (CBL) on both sides of the dryline. The dryline resembies a [open quotes]mixing zone[close quotes] containing varying portions of hot, dry air to the west side and warm, moist air from the lowest 200 m within 10 km to the east of the dryline. The mixing zone slopes eastward from the surface dryline location, then becomes a quasi-horizontal elevated moist layer above the CBL east of the dryline. Saturation-point analysis indicates that the mixing zone is characterized by a single mixing-line structure defined by the respective quasi-homogeneous air masses on either side of the dryline. Dynamical analysis reveals that near-surface westerly flow is accelerated upward and over relatively cool air above the surface by an elevated low pressure region at the dryline. Flow accelerations are nonhydrostatic at the dryline, while the flow is in hydrostatic balance both to the west and to the east of the dryline. Magnitudes of the inertial, pressure, and Coriolis accelerations are comparable to the east of the dryline, implying a considerable ageostrophic flow component as well as a quasigeostrophic linkage between the low-level jet and the west-east horizontal pressure gradient. 27 refs., 14 figs.

  14. 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.

  15. [Methods of studying the microcirculation].

    PubMed

    Shagal, D I; Tsvik, A I; Razygrin, B A

    1980-01-01

    The article shows possibilities of thermography in the study of peripheral blood circulation. Data are presented on examining the patients with diverse pathology forms by means of conjunctival biomicroscopy and television capillaroscopy of the nail bed. Evaluation of these methods and analysis of the data obtained are presented. The authors believe in more extended possibilities of applying microcirculation study methods together with thermography for disclosure of some diseases. PMID:7402036

  16. 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…

  17. 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)…

  18. 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.

  19. A double-observer method to estimate detection rate during aerial waterfowl surveys

    USGS Publications Warehouse

    Koneff, M.D.; Royle, J. Andrew; Otto, M.C.; Wortham, J.S.; Bidwell, J.K.

    2008-01-01

    We evaluated double-observer methods for aerial surveys as a means to adjust counts of waterfowl for incomplete detection. We conducted our study in eastern Canada and the northeast United States utilizing 3 aerial-survey crews flying 3 different types of fixed-wing aircraft. We reconciled counts of front- and rear-seat observers immediately following an observation by the rear-seat observer (i.e., on-the-fly reconciliation). We evaluated 6 a priori models containing a combination of several factors thought to influence detection probability including observer, seat position, aircraft type, and group size. We analyzed data for American black ducks (Anas rubripes) and mallards (A. platyrhynchos), which are among the most abundant duck species in this region. The best-supported model for both black ducks and mallards included observer effects. Sample sizes of black ducks were sufficient to estimate observer-specific detection rates for each crew. Estimated detection rates for black ducks were 0.62 (SE = 0.10), 0.63 (SE = 0.06), and 0.74 (SE = 0.07) for pilot-observers, 0.61 (SE = 0.08), 0.62 (SE = 0.06), and 0.81 (SE = 0.07) for other front-seat observers, and 0.43 (SE = 0.05), 0.58 (SE = 0.06), and 0.73 (SE = 0.04) for rear-seat observers. For mallards, sample sizes were adequate to generate stable maximum-likelihood estimates of observer-specific detection rates for only one aerial crew. Estimated observer-specific detection rates for that crew were 0.84 (SE = 0.04) for the pilot-observer, 0.74 (SE = 0.05) for the other front-seat observer, and 0.47 (SE = 0.03) for the rear-seat observer. Estimated observer detection rates were confounded by the position of the seat occupied by an observer, because observers did not switch seats, and by land-cover because vegetation and landform varied among crew areas. Double-observer methods with on-the-fly reconciliation, although not without challenges, offer one viable option to account for detection bias in aerial waterfowl

  20. Promotion Method of the Mission Concerning an Astronomical Observation

    NASA Astrophysics Data System (ADS)

    Okuda, Haruyuki

    1996-01-01

    Astronomical observation from space station can utilize big resource and there are possibilities of repairing parts and instruments. On the other hand, there are drawbacks such as strong limitation to the observing posture, difficulty in precise pointing and reduction of optical system function due to exhaust emission contamination. From these point of view, the following mission are listed as the candidate: (1) whole sky monitor observation by X rays and gamma rays; (2) high energy cosmic rays observation; (3) sun observation; and (4) cosmic dust experiment. The space station plan are not only big but also worldwide international cooperation work. So there are still many factors not cleared yet.

  1. 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

  2. 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.

  3. 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

  4. Age estimation in forensic anthropology: quantification of observer error in phase versus component-based methods.

    PubMed

    Shirley, Natalie R; Ramirez Montes, Paula Andrea

    2015-01-01

    The purpose of this study was to assess observer error in phase versus component-based scoring systems used to develop age estimation methods in forensic anthropology. A method preferred by forensic anthropologists in the AAFS was selected for this evaluation (the Suchey-Brooks method for the pubic symphysis). The Suchey-Brooks descriptions were used to develop a corresponding component-based scoring system for comparison. Several commonly used reliability statistics (kappa, weighted kappa, and the intraclass correlation coefficient) were calculated to assess observer agreement between two observers and to evaluate the efficacy of each of these statistics for this study. The linear weighted kappa was determined to be the most suitable measure of observer agreement. The results show that a component-based system offers the possibility for more objective scoring than a phase system as long as the coding possibilities for each trait do not exceed three states of expression, each with as little overlap as possible.

  5. 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.

  6. 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.

  7. 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.

  8. A simple method to evaluate the reliability of OWAS observations.

    PubMed

    de Bruijn, I; Engels, J A; van der Gulden, J W

    1998-08-01

    Slides showing nurses in different working postures were used to determine the reliability of OWAS observations. Each slide could be looked at for 3 seconds, while a new slide was shown every 30 seconds to resemble the normal practice of observation. Two observers twice scored a series of slides, some of them being identical at both viewings. To reduce effects of recall there was a time interval of 4 weeks or more between the two viewings and the slides were in a different order the second time. Different series were used to evaluate inter- and intra-observer reliability. The OWAS scores of corresponding slides were compared. In almost all comparisons percentages of agreement over 85% and kappa's over 0.6 were found, which is considered as good agreement. The procedure described seems to be a useful and simple technique to determine such reliability.

  9. 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.

  10. 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…

  11. 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…

  12. Environmental SEM and dye penetration observation on resin-tooth interface using different light curing method.

    PubMed

    Yoshikawa, Takako; Morigami, Makoto; Sadr, Alireza; Tagami, Junji

    2016-01-01

    The aim of this study was the effects of different light curing methods on marginal sealing and resin composite adaptation to the cavity wall using the dye penetration test and environmental scanning electron microscope (SEM) observations. Cylindrical cavities were prepared on cervical regions. The teeth were restored with Clearfil Liner Bond 2 V adhesive and filled with Clearfil Photo Bright or Palfique Estelite resin composites. These resins were cured with a conventional light-curing method or a slow-start curing method. After thermal cycling, the specimens were subjected to the dye penetration test to evaluate marginal sealing and adaptation of the resin composites to the cavity walls. These resin-tooth interfaces were then observed using environmental SEM. The light-cured resin composite, which exhibited increased contrast ratios during polymerization, suggests high compensation for polymerization stress using the slow-start curing method. There was a high correlation between dye penetration test and environmental SEM observation.

  13. Driving violations observed: an Australian study.

    PubMed

    Glendon, A Ian

    2007-08-01

    This study analyses 2,765 cases of driving behaviours in three Australian states - New South Wales, Queensland and Victoria. Data were gathered from in-car coordinated video and audio recording sequences in free-flowing traffic along two-, three- and four-lane highways with varying speed limits on all days of the week in daylight and fine weather conditions. Explanatory variables included driver age group and gender, passenger characteristics and vehicle age and type. Response variables included driving violations and other driving behaviours, including lane use, speeding, close following (tailgating), driver's hands position and mobile phone use. Data were analysed qualitatively and quantitatively. By focusing upon vehicle and driver characteristics, and their impact on driving behaviours, including identified violations, this study explores some implications both for future research and for traffic policy makers.

  14. 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.

  15. Observation as a Method of Diagnosis and Prescription.

    ERIC Educational Resources Information Center

    Van Nagel, Clint

    The author describes a diagnostic-prescriptive approach in which teachers use observation skills to identify visual, auditory, and behavioral deficits in learning disabled students. Teachers are advised to ask themselves seven questions, including whether a real learning disability exists; where the student is currently functioning in reading,…

  16. Observational studies of highly evolved cataclysmic variables

    NASA Astrophysics Data System (ADS)

    Uthas, Helena

    2011-05-01

    According to standard evolutionary theory for cataclysmic variables (CVs), angular momentum loss drives CVs to initially evolve from longer to shorter orbital periods until a minimum period is reached (approx 80 min). At roughly this stage, the donors becomes degenerate, expand in size, and the systems move towards longer Porb. Theory predicts that 70% of all CVs should have passed their minimum period and have sub-stellar donors, but until recently, no such systems were known. I present one CV showing evidence of harbouring a sub-dwarf donor, SDSS J1507+52. Due to the system's unusually short Porb of about 65 min, and very high space velocity, two origins for SDSS J1507+52 have been proposed; either the system was formed from a young WD/brown-dwarf binary, or the system is a halo CV. In order to distinguish between these two theories, I present UV spectroscopy and find a metallicity consistent with halo origin. Systems close to Pmin are expected to have low accretion rates. Some of these CVs show absorption in their spectra, implying that the underlying WD is exposed. This yields a rare opportunity to study the WD in a CV. I introduce two new systems showing WD signatures in their light curves and spectra, SDSS J1457+51 and BW Scl. Despite the fact that CVs close to Pmin should be faint, we find systems that are much too bright for their Porb. Such a system is T Pyx - a recurrent nova with an unusually high accretion rate and a photometrically determined Porb < 2 hr. T Pyx is about 2 times brighter than any other CV at its period. However, to confirm its evolutionary status, a more reliable period determination is needed. Here, I present a spectroscopic study, confirming T Pyx as a short-period CV. In this thesis, I discuss what implications these systems may have on the current understanding of CV evolution, and the importance of studying individual systems in general.

  17. Quality Reporting of Multivariable Regression Models in Observational Studies

    PubMed Central

    Real, Jordi; Forné, Carles; Roso-Llorach, Albert; Martínez-Sánchez, Jose M.

    2016-01-01

    Abstract Controlling for confounders is a crucial step in analytical observational studies, and multivariable models are widely used as statistical adjustment techniques. However, the validation of the assumptions of the multivariable regression models (MRMs) should be made clear in scientific reporting. The objective of this study is to review the quality of statistical reporting of the most commonly used MRMs (logistic, linear, and Cox regression) that were applied in analytical observational studies published between 2003 and 2014 by journals indexed in MEDLINE. Review of a representative sample of articles indexed in MEDLINE (n = 428) with observational design and use of MRMs (logistic, linear, and Cox regression). We assessed the quality of reporting about: model assumptions and goodness-of-fit, interactions, sensitivity analysis, crude and adjusted effect estimate, and specification of more than 1 adjusted model. The tests of underlying assumptions or goodness-of-fit of the MRMs used were described in 26.2% (95% CI: 22.0–30.3) of the articles and 18.5% (95% CI: 14.8–22.1) reported the interaction analysis. Reporting of all items assessed was higher in articles published in journals with a higher impact factor. A low percentage of articles indexed in MEDLINE that used multivariable techniques provided information demonstrating rigorous application of the model selected as an adjustment method. Given the importance of these methods to the final results and conclusions of observational studies, greater rigor is required in reporting the use of MRMs in the scientific literature. PMID:27196467

  18. Effects of the observation method (direct v. from video) and of the presence of an observer on behavioural results in veal calves.

    PubMed

    Leruste, H; Bokkers, E A M; Sergent, O; Wolthuis-Fillerup, M; van Reenen, C G; Lensink, B J

    2013-11-01

    This study aimed at assessing the effect of the observation method (direct or from video) and the effect of the presence of an observer on the behavioural results in veal calves kept on a commercial farm. To evaluate the effect of the observation method, 20 pens (four to five calves per pen) were observed by an observer for 60 min (two observation sessions of 30 min) and video-recorded at the same time. To evaluate the effect of the presence of the observer in front of the pen, 24 pens were video-recorded on 4 consecutive days and an observer was present in front of each pen for 60 min (two observation sessions of 30 min) on the third day. Behaviour was recorded using instantaneous scan sampling. For the study of the observer's effect, the analysis was limited to the posture, abnormal oral behaviour and manipulation of substrates. The two observation methods gave similar results for the time spent standing, but different results for all other behaviours. The presence of an observer did not affect the behaviour of calves at day level; however, their behaviour was affected when the observer was actually present in front of the pens. A higher percentage of calves were standing and were manipulating substrate in the presence of the observer, but there was no effect on abnormal oral behaviour. In conclusion, direct observations are a more suitable observation method than observations from video recordings for detailed behaviours in veal calves. The presence of an observer has a short-term effect on certain behaviours of calves that will have to be taken into consideration when monitoring these behaviours.

  19. [Observation of repair of wounded rat skin by affinity histochemical method of SJA].

    PubMed

    Li, Z H; Jin, H L; Zhu, J Z

    1999-02-01

    Time expression of SJA tissue receptors surrounding wounded skin of 40 rats was studied by affinity histochemical method. The results were compared to that by EGFR immunohistochemical method and c-myc situ hydridization method. It was observed that SJA receptors began to decrease after the skin was injured and reached the lowest quantities in 15 minutes. After that, they began to increase and reached the highest quantities in 2 hours. It needs to be further studied whether there is the correlation between SJA receptors and EGFR has the function of repairing wounded skin. PMID:12536384

  20. A prospective, observational study of a chest pain observation unit in a British hospital

    PubMed Central

    Goodacre, S; Morris, F; Campbell, S; Arnold, J; Angelini, K

    2002-01-01

    Objectives: To establish a chest pain observation unit, monitor its performance in terms of appropriate discharge after assessment, and estimate the cost per patient. Methods: Prospective, observational, cohort study of patients attending a large, city, teaching hospital accident and emergency department between 1 March 1999 and 29 February 2000 with acute undifferentiated chest pain. Patients were managed on a chest pain observation unit, entailing two to six hours of observation, serial electrocardiograph recording, cardiac enzyme measurement, and, where appropriate, exercise stress test. Patients were discharged home if all tests were negative and admitted to hospital if tests were positive or equivocal. The following outcomes were measured—proportion of participants discharged after assessment; clinical status three days after discharge; cardiac events and procedures during the following six months; and cost of assessment and admission. Results: Twenty three participants (4.3%) had a final diagnosis of myocardial infarction. All were detected and admitted to hospital. A total of 461 patients (86.3%) were discharged after assessment, 357 (66.9%) avoided hospital admission entirely. At review three days later these patients had no new ECG changes and only one raised troponin T measurement. In the six months after assessment, three cardiac deaths, two myocardial infarctions, and two revascularisation procedures were recorded among those discharged. The mean cost of assessment and hospital admission was £221 per patient, or £323 if subsequent interventional cardiology costs were included. Conclusions: The chest pain observation unit is a practical alternative to routine care for acute chest pain in the United Kingdom. Negative assessment effectively rules out immediate, serious morbidity, but not longer term morbidity and mortality. Costs seem to be similar to routine care. PMID:11904256

  1. Nuclear structure from direct reactions with rare isotopes: observables, methods and highlights

    NASA Astrophysics Data System (ADS)

    Obertelli, Alexandre

    2016-09-01

    An overview of direct reactions employed for nuclear structure studies is presented. The basic and most used analysis methods of elastic and inelastic scattering, transfer reactions and intermediate-energy removal reactions are reviewed. The most relevant observables from direct reactions regarding the nuclear many-body problem, as well as related experimental techniques, are illustrated through recent achievements with unstable nuclei.

  2. 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…

  3. Folic Acid Supplementation and Preterm Birth: Results from Observational Studies

    PubMed Central

    Franchi, Massimo

    2014-01-01

    Introduction. 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. Aim of the Study. The aim of this review was to examine the results from recent observational studies about the effect of FA supplementation on PTB. Materials and Methods. 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. Results. 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. PMID:24724083

  4. 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. PMID:26654767

  5. 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; Vicarelli, Marta; Waterhouse, Jon; Weeks, Brian

    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.

  6. The value of site-based observations complementary to naturalistic driving observations: a pilot study on the right turn manoeuvre.

    PubMed

    van Nes, Nicole; Christoph, Michiel; Hoedemaeker, Marika; van der Horst, Richard A

    2013-09-01

    Naturalistic driving studies are increasingly applied in different shapes and sizes. The European project PROLOGUE has investigated the value and feasibility of a large-scale naturalistic driving study in Europe. Within PROLOGUE several pilot studies have been conducted in different countries. The Dutch field trial investigated the value and feasibility of adding site-based observations to in-vehicle observations. In this trial, one intersection was equipped with cameras for site-based observation. Additionally eight cars were equipped of drivers crossing this intersection regularly. On this small scale, combining the two observation methods turned out to be technically feasible. It was possible to recognise the instrumented vehicles in the site-based video data, to match cases from the different observations and the speed measures from the separate studies appeared to be similar. The value of combining these two observation methods lies in the possibility to enrich the data from one study with complementary data from the other study. The study illustrated that each type of observation has its unique values. From in-vehicle data it is possible to look in detail at the driving behaviour of the participants over time and in different situations. The site-based study offers information about the position and speed of other road users surrounding the participant's vehicle, including vulnerable road users such as cyclists and pedestrians. Two values of adding site-based observations to in-vehicle observations were identified: to obtain more in depth understanding and to relate the behaviour of participants of the naturalistic driving study to behaviour of the full population of drivers (non-participants). For a future (large-scale) naturalistic driving study two research topics are identified that could benefit from these complementary observations: driving behaviour in relation to specific infrastructure and the interaction between drivers and vulnerable road users.

  7. Factors affecting recruitment to an observational multicentre palliative care study

    PubMed Central

    Stone, Patrick C; Gwilliam, Bridget; Keeley, Vaughan; Todd, Chris; Kelly, Laura C; Barclay, Stephen

    2013-01-01

    Objectives To identify those factors which adversely affected recruitment to a large multicentre palliative care study. Methods Patient accrual to a multicentre, observational, palliative care study was monitored at three critical junctures in the research process. (1) Eligibility—did the patient fulfil the study entry criteria? (2) Accessibility—was it possible to access the patient to be able to inform them about the study? (3) Consent—did the patient agree to participate in the study? The reasons why patients were ineligible, inaccessible or refused consent were recorded. Results 12 412 consecutive referrals to participating clinical services were screened for study inclusion of whom 5394 (43%) were deemed to be ineligible. Of the remaining patients 4617/7018 (66%) were inaccessible to the research team. The most common reasons being precipitous death, ‘gatekeeping’ by clinical staff or rapid discharge. Of the 2410 patients who were visited by the research team and asked to participate in the study 1378 (57%) declined. Overall 8.2% (1018/12 412) of patients screened participated in the study. There were significant differences in recruitment patterns between hospice inpatient units, hospital support and community palliative care teams. Conclusions Systematic monitoring and analysis of patient flows through the clinical trial accrual process provided valuable insights about the reasons for failure to recruit patients to a clinical trial and may help to improve recruitment in future studies. PMID:24644750

  8. The joint observation and study project for slowly rotating asteroids

    NASA Astrophysics Data System (ADS)

    Wang, Xiaobin; Muninonen, karri; Han, Xianming L.; Wang, Yibo

    2015-08-01

    The study for the spin rates and shapes of asteroids provides us important information to understand asteroids' structure and their physical processes. For example, a single Maxwellian distribution of the spin rates of larger asteroids (e.g. larger than 50km in diameter) reflects they had undergone collison history; a more dispersed distribution of smaller asteroids may be associated with the affect of radiation pressure torques( Pravec& Harris2000). Therefore, larger samples of spin parameters are needed for understanding deeply the evolution of asteroids. Meanwhile, some special subsets of asteroids, such as the slow rotators which probably represent a different physical process for asteroids, can open other windows to understand asteroids. Here we focus on a subset of larger asteroids with spin rates around 1 or 0.5 revolution per day. For these asteroids, the same rotational phases are observed repeatly by a telescope in different time. Under such cases, some ambigous spin periods are guessed, and it is impossible to determine their shapes. For determining the accurate spin parameters and shapes of these asteroids, a collaboration among several countries was established in 2014. Till now, the joint observations for a few of slow rotators have been made by several different telescopes distributed in China, USA and Chile. As samples, here we present new jiont observations in 2014 and analysis results for asteroids (346) Hermentaria and (168) Sibylla.Considering reasonable shapes of asteroids, the spin parameters of the two asteroids are analyzed carefully. Firstly, the procedure of analysis involves the MCMC method to find the initial spin parameters, which is based on a triaxial ellipsoid shape and a Lommel-Seeliger surface scattering law(Muinonen et al.2014). Then, the fine spin parameters accompanying with uncertainties and convex shapes of the asteroids are derived using the light curve inversion method(Kaasalainen et al 2002) and virtual photometric method

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

    PubMed

    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

  10. 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

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

    NASA Astrophysics Data System (ADS)

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

    2016-03-01

    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.

  12. 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

  13. 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. PMID:25162234

  14. 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

  15. 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.

  16. Performance of statistical methods to correct food intake distribution: comparison between observed and estimated usual intake.

    PubMed

    Verly-Jr, Eliseu; Oliveira, Dayan C R S; Fisberg, Regina M; Marchioni, Dirce Maria L

    2016-09-01

    There are statistical methods that remove the within-person random error and estimate the usual intake when there is a second 24-h recall (24HR) for at least a subsample of the study population. We aimed to compare the distribution of usual food intake estimated by statistical models with the distribution of observed usual intake. A total of 302 individuals from Rio de Janeiro (Brazil) answered twenty, non-consecutive 24HR; the average length of follow-up was 3 months. The usual food intake was considered as the average of the 20 collection days of food intake. Using data sets with a pair of 2 collection days, usual percentiles of intake of the selected foods using two methods were estimated (National Cancer Institute (NCI) method and Multiple Source Method (MSM)). These estimates were compared with the percentiles of the observed usual intake. Selected foods comprised a range of parameter distributions: skewness, percentage of zero intakes and within- and between-person intakes. Both methods performed well but failed in some situations. In most cases, NCI and MSM produced similar percentiles between each other and values very close to the true intake, and they better represented the usual intake compared with 2-d mean. The smallest precision was observed in the upper tail of the distribution. In spite of the underestimation and overestimation of percentiles of intake, from a public health standpoint, these biases appear not to be of major concern. PMID:27523187

  17. Observation of Paramagnetic Supercurrent in Mesoscopic Superconducting Rings and Disks Using Multiple-Small Method

    NASA Astrophysics Data System (ADS)

    Kanda, A.; Baelus, B. J.; Peeters, F. M.; Kadowaki, K.; Ootuka, Y.

    2005-08-01

    Responses of mesoscopic superconducting rings and disks to perpendicular magnetic fields are studied by using the multiple-small-tunnel-junction method, in which transport properties of several small tunnel junctions attached to the sample are measured simultaneously. This allows us for a direct experimental observation of the paramagnetic supercurrent, which is closely related to the paramagnetic Meissner effect. The results are compared with numerical results based on the nonlinear Ginzburg-Landau theory.

  18. 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.

  19. Concatenation of observed grasp phases with observer's distal movements: a behavioural and TMS study.

    PubMed

    De Stefani, Elisa; Innocenti, Alessandro; De Marco, Doriana; Gentilucci, Maurizio

    2013-01-01

    The present study aimed at determining how actions executed by two conspecifics can be coordinated with each other, or more specifically, how the observation of different phases of a reaching-grasping action is temporary related to the execution of a movement of the observer. Participants observed postures of initial finger opening, maximal finger aperture, and final finger closing of grasp after observation of an initial hand posture. Then, they opened or closed their right thumb and index finger (experiments 1, 2 and 3). Response times decreased, whereas acceleration and velocity of actual finger movements increased when observing the two late phases of grasp. In addition, the results ruled out the possibility that this effect was due to salience of the visual stimulus when the hand was close to the target and confirmed an effect of even hand postures in addition to hand apparent motion due to the succession of initial hand posture and grasp phase. In experiments 4 and 5, the observation of grasp phases modulated even foot movements and pronunciation of syllables. Finally, in experiment 6, transcranial magnetic stimulation applied to primary motor cortex 300 ms post-stimulus induced an increase in hand motor evoked potentials of opponens pollicis muscle when observing the two late phases of grasp. These data suggest that the observation of grasp phases induced simulation which was stronger during observation of finger closing. This produced shorter response times, greater acceleration and velocity of the successive movement. In general, our data suggest best concatenation between two movements (one observed and the other executed) when the observed (and simulated) movement was to be accomplished. The mechanism joining the observation of a conspecific's action with our own movement may be precursor of social functions. It may be at the basis for interactions between conspecifics, and related to communication between individuals.

  20. Bias correction methods for regional climate model simulations considering the distributional parametric uncertainty underlying the observations

    NASA Astrophysics Data System (ADS)

    Kim, Kue Bum; Kwon, Hyun-Han; Han, Dawei

    2015-11-01

    In this paper, we present a comparative study of bias correction methods for regional climate model simulations considering the distributional parametric uncertainty underlying the observations/models. In traditional bias correction schemes, the statistics of the simulated model outputs are adjusted to those of the observation data. However, the model output and the observation data are only one case (i.e., realization) out of many possibilities, rather than being sampled from the entire population of a certain distribution due to internal climate variability. This issue has not been considered in the bias correction schemes of the existing climate change studies. Here, three approaches are employed to explore this issue, with the intention of providing a practical tool for bias correction of daily rainfall for use in hydrologic models ((1) conventional method, (2) non-informative Bayesian method, and (3) informative Bayesian method using a Weather Generator (WG) data). The results show some plausible uncertainty ranges of precipitation after correcting for the bias of RCM precipitation. The informative Bayesian approach shows a narrower uncertainty range by approximately 25-45% than the non-informative Bayesian method after bias correction for the baseline period. This indicates that the prior distribution derived from WG may assist in reducing the uncertainty associated with parameters. The implications of our results are of great importance in hydrological impact assessments of climate change because they are related to actions for mitigation and adaptation to climate change. Since this is a proof of concept study that mainly illustrates the logic of the analysis for uncertainty-based bias correction, future research exploring the impacts of uncertainty on climate impact assessments and how to utilize uncertainty while planning mitigation and adaptation strategies is still needed.

  1. A passive acoustic monitoring method applied to observation and group size estimation of finless porpoises.

    PubMed

    Wang, Kexiong; Wang, Ding; Akamatsu, Tomonari; Li, Songhai; Xiao, Jianqiang

    2005-08-01

    The present study aimed at determining the detection capabilities of an acoustic observation system to recognize porpoises under local riverine conditions and compare the results with sighting observations. Arrays of three to five acoustic data loggers were stationed across the main channel of the Tian-e-zhou Oxbow of China's Yangtze River at intervals of 100-150 m to record sonar signals of free-ranging finless porpoises (Neophocaena phocaenoides). Acoustic observations, concurrent with visual observations, were conducted at two occasions on 20-22 October 2003 and 17-19 October 2004. During a total of 42 h of observation, 316 finless porpoises were sighted and 7041 sonar signals were recorded by loggers. The acoustic data loggers recorded ultrasonic signals of porpoises clearly, and detected the presence of porpoises with a correct detection level of 77.6% and a false alarm level of 5.8% within an effective distance of 150 m. Results indicated that the stationed passive acoustic observation method was effective in detecting the presence of porpoises and showed potential in estimating the group size. A positive linear correlation between the number of recorded signals and the group size of sighted porpoises was indicated, although it is faced with some uncertainty and requires further investigation. PMID:16158672

  2. A passive acoustic monitoring method applied to observation and group size estimation of finless porpoises.

    PubMed

    Wang, Kexiong; Wang, Ding; Akamatsu, Tomonari; Li, Songhai; Xiao, Jianqiang

    2005-08-01

    The present study aimed at determining the detection capabilities of an acoustic observation system to recognize porpoises under local riverine conditions and compare the results with sighting observations. Arrays of three to five acoustic data loggers were stationed across the main channel of the Tian-e-zhou Oxbow of China's Yangtze River at intervals of 100-150 m to record sonar signals of free-ranging finless porpoises (Neophocaena phocaenoides). Acoustic observations, concurrent with visual observations, were conducted at two occasions on 20-22 October 2003 and 17-19 October 2004. During a total of 42 h of observation, 316 finless porpoises were sighted and 7041 sonar signals were recorded by loggers. The acoustic data loggers recorded ultrasonic signals of porpoises clearly, and detected the presence of porpoises with a correct detection level of 77.6% and a false alarm level of 5.8% within an effective distance of 150 m. Results indicated that the stationed passive acoustic observation method was effective in detecting the presence of porpoises and showed potential in estimating the group size. A positive linear correlation between the number of recorded signals and the group size of sighted porpoises was indicated, although it is faced with some uncertainty and requires further investigation.

  3. 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

  4. Cause versus association in observational studies in psychopharmacology.

    PubMed

    Andrade, Chittaranjan

    2014-08-01

    Hypotheses may be generated (and conclusions drawn) from observational studies in areas where information from randomized controlled trials (RCTs) is unavailable. However, observational studies can only establish that significant associations exist between predictor and outcome variables. Observational studies cannot establish that the associations identified represent cause-and-effect relationships. This article discusses examples of associations that were identified in observational studies and that were subsequently refuted in RCTs. Examples are also provided of associations that have yet to be confirmed or refuted but that are nevertheless influential in psychopharmacologic practice. Explanations are offered about how confounding might explain significant relationships between variables that are not related by cause and effect. As a conclusion of this exercise, clinicians are cautioned against placing too much reliance on the findings of observational research.

  5. 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%…

  6. 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

  7. 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.…

  8. 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…

  9. An Observational Study of Social Processes in Microcomputer Classrooms.

    ERIC Educational Resources Information Center

    Feldmann, Shirley C.; And Others

    This observational study examined student and teacher verbal and nonverbal behaviors in microcomputer classrooms in a high school where most of the students are Black, Hispanic, or Asian, and almost half of them are classified as economically disadvantaged. A total of 125 students in grades 9 to 12 were observed, with 47 students in marketing, 18…

  10. MOOSES: Multiple Option Observation System for Experimental Studies.

    ERIC Educational Resources Information Center

    Tapp, Jon; Wehby, Joseph

    The Multiple Option Observation System for Experimental Studies (MOOSES) is a flexible data collection and analysis package for applied behavioral research that addresses the needs of researchers interested in live coding of observational data. MOOSES allows the researcher to design a coding system for a particular research question. General types…

  11. Aneurysm Study of Pipeline in an Observational Registry (ASPIRe)

    PubMed Central

    Kallmes, David F.; Brinjikji, Waleed; Boccardi, Edoardo; Ciceri, Elisa; Diaz, Orlando; Tawk, Rabih; Woo, Henry; Jabbour, Pascal; Albuquerque, Felipe; Chapot, Rene; Bonafe, Alain; Dashti, Shervin R.; Almandoz, Josser E. Delgado; Given, Curtis; Kelly, Michael E.; Cross, DeWitte T.; Duckwiler, Gary; Razack, Nasser; Powers, Ciaran J.; Fischer, Sebastian; Lopes, Demetrius; Harrigan, Mark R.; Huddle, Daniel; Turner, Raymond; Zaidat, Osama O.; Defreyne, Luc; Pereira, Vitor Mendes; Cekirge, Saruhan; Fiorella, David; Hanel, Ricardo A.; Lylyk, Pedro; McDougall, Cameron; Siddiqui, Adnan; Szikora, Istvan; Levy, Elad

    2016-01-01

    Background and Objective Few prospective studies exist evaluating the safety and efficacy of the Pipeline Embolization Device (PED) in the treatment of intracranial aneurysms. The Aneurysm Study of Pipeline In an observational Registry (ASPIRe) study prospectively analyzed rates of complete aneurysm occlusion and neurologic adverse events following PED treatment of intracranial aneurysms. Materials and Methods We performed a multicenter study prospectively evaluating patients with unruptured intracranial aneurysms treated with PED. Primary outcomes included (1) spontaneous rupture of the Pipeline-treated aneurysm; (2) spontaneous nonaneurysmal intracranial hemorrhage (ICH); (3) acute ischemic stroke; (4) parent artery stenosis, and (5) permanent cranial neuropathy. Secondary endpoints were (1) treatment success and (2) morbidity and mortality at the 6-month follow-up. Vascular imaging was evaluated at an independent core laboratory. Results One hundred and ninety-one patients with 207 treated aneurysms were included in this registry. The mean aneurysm size was 14.5 ± 6.9 mm, and the median imaging follow-up was 7.8 months. Twenty-four aneurysms (11.6%) were small, 162 (78.3%) were large and 21 (10.1%) were giant. The median clinical follow-up time was 6.2 months. The neurological morbidity rate was 6.8% (13/191), and the neurological mortality rate was 1.6% (3/191). The combined neurological morbidity/mortality rate was 6.8% (13/191). The most common adverse events were ischemic stroke (4.7%, 9/191) and spontaneous ICH (3.7%, 7/191). The complete occlusion rate at the last follow-up was 74.8% (77/103). Conclusions Our prospective postmarket study confirms that PED treatment of aneurysms in a heterogeneous patient population is safe with low rates of neurological morbidity and mortality. Patients with angiographic follow-up had complete occlusion rates of 75% at 8 months.

  12. Aneurysm Study of Pipeline in an Observational Registry (ASPIRe)

    PubMed Central

    Kallmes, David F.; Brinjikji, Waleed; Boccardi, Edoardo; Ciceri, Elisa; Diaz, Orlando; Tawk, Rabih; Woo, Henry; Jabbour, Pascal; Albuquerque, Felipe; Chapot, Rene; Bonafe, Alain; Dashti, Shervin R.; Almandoz, Josser E. Delgado; Given, Curtis; Kelly, Michael E.; Cross, DeWitte T.; Duckwiler, Gary; Razack, Nasser; Powers, Ciaran J.; Fischer, Sebastian; Lopes, Demetrius; Harrigan, Mark R.; Huddle, Daniel; Turner, Raymond; Zaidat, Osama O.; Defreyne, Luc; Pereira, Vitor Mendes; Cekirge, Saruhan; Fiorella, David; Hanel, Ricardo A.; Lylyk, Pedro; McDougall, Cameron; Siddiqui, Adnan; Szikora, Istvan; Levy, Elad

    2016-01-01

    Background and Objective Few prospective studies exist evaluating the safety and efficacy of the Pipeline Embolization Device (PED) in the treatment of intracranial aneurysms. The Aneurysm Study of Pipeline In an observational Registry (ASPIRe) study prospectively analyzed rates of complete aneurysm occlusion and neurologic adverse events following PED treatment of intracranial aneurysms. Materials and Methods We performed a multicenter study prospectively evaluating patients with unruptured intracranial aneurysms treated with PED. Primary outcomes included (1) spontaneous rupture of the Pipeline-treated aneurysm; (2) spontaneous nonaneurysmal intracranial hemorrhage (ICH); (3) acute ischemic stroke; (4) parent artery stenosis, and (5) permanent cranial neuropathy. Secondary endpoints were (1) treatment success and (2) morbidity and mortality at the 6-month follow-up. Vascular imaging was evaluated at an independent core laboratory. Results One hundred and ninety-one patients with 207 treated aneurysms were included in this registry. The mean aneurysm size was 14.5 ± 6.9 mm, and the median imaging follow-up was 7.8 months. Twenty-four aneurysms (11.6%) were small, 162 (78.3%) were large and 21 (10.1%) were giant. The median clinical follow-up time was 6.2 months. The neurological morbidity rate was 6.8% (13/191), and the neurological mortality rate was 1.6% (3/191). The combined neurological morbidity/mortality rate was 6.8% (13/191). The most common adverse events were ischemic stroke (4.7%, 9/191) and spontaneous ICH (3.7%, 7/191). The complete occlusion rate at the last follow-up was 74.8% (77/103). Conclusions Our prospective postmarket study confirms that PED treatment of aneurysms in a heterogeneous patient population is safe with low rates of neurological morbidity and mortality. Patients with angiographic follow-up had complete occlusion rates of 75% at 8 months. PMID:27610126

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

    PubMed Central

    Bottle, A; Aylin, P

    2015-01-01

    Study question What is the association between day of delivery and measures of quality and safety of maternity services, particularly comparing weekend with weekday performance? Methods 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. Study answer and limitations 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. What this study adds This study provides an evaluation of the “weekend effect” in obstetric care

  15. A Method for the Systematic Observation of Examiner Behavior during Psychoeducational Assessments.

    ERIC Educational Resources Information Center

    Strein, William

    1984-01-01

    Describes a specific empirical method for the systematic observation of examiner behavior during psychoeducational assessments, the Systematic Observation Scale for Assessments (SOS-A). Discusses development of the instrument and presents data on intra- and interobserver agreement. The instrument is regarded as an initially adequate method for…

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

    USGS Publications Warehouse

    Miller, Holly; 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.

  17. Cardiovascular events in patients with obesity: an observational study

    PubMed Central

    Buitrago, Francisco; Calvo, Juan Ignacio; Redondo-López, Verónica; Cañón-Barroso, Lourdes; Rodríguez-Pérez, Leoncio; Hinojosa-Díaz, José Francisco

    2010-01-01

    Background Overweight and obesity are positively correlated with increased risk of morbidity and mortality. Aim To evaluate whether obesity may be considered an independent cardiovascular risk factor in patients of ages from 35 to 74 years followed-up for 10 years. Design of study Observational, longitudinal retrospective study. Setting Primary care practices in Badajoz (Spain). Method A cohort of 899 patients (mean 55.7 years; 58.2% female) without evidence of cardiovascular disease was studied. Results A total of 33.5% of the population were obese (body mass index ≥30 kg/m2). Patients meeting the obesity criteria were more commonly female (36.6%) and were older, had higher mean values of blood pressure and triglycerides, higher percentages of diabetes, and higher coronary risk using either the original Framingham or the Framingham function calibrated for the Spanish population (Framingham-REGICOR). During the follow-up period, the rates of cardiovascular events and death in patients with obesity tended to be higher: 16.3% versus 11.7%, P = 0.056 and 4.7% versus 2.2%, P<0.05, respectively. In the final model of the logistic regression multivariate analysis, the significant predictors of cardiovascular events in patients with obesity were age, sex (male), diastolic blood pressure, diabetes, and smoking. The highest odds ratio corresponded to smoking (odds ratio 2.03; 95% confidence interval = 1.22 to 3.38). Conclusion Obesity may not be considered an independent cardiovascular risk factor in patients aged from 35 to 74 years followed-up for 10 years. PMID:20822691

  18. 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

  19. Non-destructive dental-age calculation methods in adults: intra- and inter-observer effects.

    PubMed

    Willems, Guy; Moulin-Romsee, Christian; Solheim, Tore

    2002-05-23

    The aim of the present study was to obtain data on the reliability and reproducibility of two non-destructive dental-age estimation methods in adults by calculating inter- and intra-observer effects. Both a morphological and a radiological technique available in the scientific literature were evaluated on a number of recently extracted teeth: the morphological technique was evaluated on a total of 160 teeth by two examiners, while three examiners applied the radiological technique on apical radiographs of 72 extracted teeth. Paired t-tests were used to calculate intra- and inter-observer differences. For the morphological method, both examiners were able to produce dental-age estimations that did not differ significantly from the real age of the teeth, obtaining a mean error between 0.5 and 1.8 years and a standard deviation of this error between 9.0 and 11.3 years. When using the radiological technique according to the original protocol, all three examiners produced age estimations that were statistically comparable to the real age of the teeth with a mean error of 0.5-2.5 years and a standard deviation of 4.6-9.8 years. For both techniques, intra-observer differences were observed. Based on the results of this study, it can be concluded that both non-destructive dental-age estimation techniques were able to produce reasonably accurate dental-age estimations, at least when these techniques were applied appropriately. However, the forensic odontologist is recommended to use different age estimation techniques and perform repetitive measurements in order to verify the reproducibility of the calculations performed. PMID:12062945

  20. 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

  1. Regional Satellite Observations for Dryland Degradation Studies (Invited)

    NASA Astrophysics Data System (ADS)

    Prince, S. D.

    2009-12-01

    The lack of global scale maps of degraded drylands remains a significant obstacle to identification, prevention and mitigation of desertification. To fill this gap, maps are needed that have some or all of the following characteristics. i Use quantitative variables that have defined biogeophysical meaning. ii Identify areas that are currently in a state of desertification as well as showing areas having higher risk of degradation. iii Provide a synopsis of the condition of land over a number of years, not only a single point in time. iv Repeatable, using consistent observations and an explicit methodology, with a clear link to methods for monitoring and change detection. v Flexible enough to allow adaptation to regional needs while not compromising the ability to compare regions on the basis of consistent criteria. vi At a scale adequate to identify the normal spatial scales of desertification - sub-national, but greater than individual land holdings. vii Down-scalable to allow the specific factors and processes responsible for degradation in a specific location to be identified. viii Can be used as state variables in household-scale studies. ix Up-scalable to allow impacts on processes such as climate change that are relevant at a coarse spatial resolution. x Presented in a data base with appropriate additional maps, such as topography, land use, soil properties, and rainfall, to allow interpretation. xi Can be validated and have information on potential error. xii Not reliant on a single data source nor on a single institution.

  2. 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…

  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. 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. PMID:27327657

  6. 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.

  7. Using Kinect™ sensor in observational methods for assessing postures at work.

    PubMed

    Diego-Mas, Jose Antonio; Alcaide-Marzal, Jorge

    2014-07-01

    This paper examines the potential use of Kinect™ range sensor in observational methods for assessing postural loads. Range sensors can detect the position of the joints at high sampling rates without attaching sensors or markers directly to the subject under study. First, a computerized OWAS ergonomic assessment system was implemented to permit the data acquisition from Kinect™ and data processing in order to identify the risk level of each recorded postures. Output data were compared with the results provided by human observers, and were used to determine the influence of the sensor view angle relative to the worker. The tests show high inter-method agreement in the classification of risk categories (Proportion agreement index = 0.89 κ = 0.83) when the tracked subject is facing the sensor. The camera's point of view relative to the position of the tracked subject significantly affects the correct classification of the postures. Although the results are promising, some aspects involved in the use of low-cost range sensors should be further studied for their use in real environments.

  8. Active Bleeding after Cardiac Surgery: A Prospective Observational Multicenter Study

    PubMed Central

    Fellahi, Jean-Luc; Bertet, Héléna; Faucanie, Marie; Amour, Julien; Blanloeil, Yvonnick; Lanquetot, Hervé; Ouattara, Alexandre; Picot, Marie Christine

    2016-01-01

    Main Objectives To estimate the incidence of active bleeding after cardiac surgery (AB) based on a definition directly related on blood flow from chest drainage; to describe the AB characteristics and its management; to identify factors of postoperative complications. Methods AB was defined as a blood loss > 1.5 ml/kg/h for 6 consecutive hours within the first 24 hours or in case of reoperation for hemostasis during the first 12 postoperative hours. The definition was applied in a prospective longitudinal observational study involving 29 French centers; all adult patients undergoing cardiac surgery with cardiopulmonary bypass were included over a 3-month period. Perioperative data (including blood product administration) were collected. To study possible variation in clinical practice among centers, patients were classified into two groups according to the AB incidence of the center compared to the overall incidence: “Low incidence” if incidence is lower and “High incidence” if incidence is equal or greater than overall incidence. Logistic regression analysis was used to identify risk factors of postoperative complications. Results Among 4,904 patients, 129 experienced AB (2.6%), among them 52 reoperation. Postoperative bleeding loss was 1,000 [820;1,375] ml and 1,680 [1,280;2,300] ml at 6 and 24 hours respectively. Incidence of AB varied between centers (0 to 16%) but was independent of in-centre cardiac surgical experience. Comparisons between groups according to AB incidence showed differences in postoperative management. Body surface area, preoperative creatinine, emergency surgery, postoperative acidosis and red blood cell transfusion were risk factors of postoperative complication. Conclusions A blood loss > 1.5 ml/kg/h for 6 consecutive hours within the first 24 hours or early reoperation for hemostasis seems a relevant definition of AB. This definition, independent of transfusion, adjusted to body weight, may assess real time bleeding occurring

  9. Study on Bridge of Violin by Photoelastic Observation

    NASA Astrophysics Data System (ADS)

    Matsutani, Akihiro

    2002-10-01

    The stress of the bridge of a violin was observed by means of the photoelastic method, and a frequency analysis of the tones of two violins was performed. It was found that the stress of the bridge and the tone of the violin depended on the shape and the tilt of the bridge, the direction of force applied by bowing and so on. In addition, it was demonstrated scientifically that adjustment of the instrument is very important and that players should maintain the instrument properly. The proposed visualization method may be helpful for violin teaching and for practice of bowing skills of amateur violinists.

  10. 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.

  11. 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.

  12. CLEM Methods for Studying Primary Cilia.

    PubMed

    Macaluso, Frank P; Perumal, Geoffrey S; Kolstrup, Johan; Satir, Peter

    2016-01-01

    CLEM (correlated light and electron microscope) imaging is a highly useful technique for examining primary cilia. With CLEM, it is possible to determine the distribution of tagged proteins along the ciliary membrane and axoneme with high precision. Scanning electron microscopy (SEM) permits measurement of ciliary length and orientation in relation to nearby cellular structures in a 3D image; in optimal cases, this can be combined with superresolution microscopy of selected ciliary components as they enter or leave the cilium. This chapter discusses CLEM methods. In the method described in detail, samples are completely processed for sequential fluorescence and SEM observation. This method is ideal for robust antibody localization and minimizes image manipulation in correlating the fluorescent and SEM images. Alternative methods prepare samples for fluorescence imaging followed by processing for SEM then observation in the SEM. This method is ideal for optimal fluorescence imaging, particularly live cell imaging. PMID:27514923

  13. Inverse Method for Estimating the Spatial Variability of Soil Particle Size Distribution from Observed Soil Moisture

    SciTech Connect

    Pan, Feifei; Peters-lidard, Christa D.; King, Anthony Wayne

    2010-11-01

    Soil particle size distribution (PSD) (i.e., clay, silt, sand, and rock contents) information is one of critical factors for understanding water cycle since it affects almost all of water cycle processes, e.g., drainage, runoff, soil moisture, evaporation, and evapotranspiration. With information about soil PSD, we can estimate almost all soil hydraulic properties (e.g., saturated soil moisture, field capacity, wilting point, residual soil moisture, saturated hydraulic conductivity, pore-size distribution index, and bubbling capillary pressure) based on published empirical relationships. Therefore, a regional or global soil PSD database is essential for studying water cycle regionally or globally. At the present stage, three soil geographic databases are commonly used, i.e., the Soil Survey Geographic database, the State Soil Geographic database, and the National Soil Geographic database. Those soil data are map unit based and associated with great uncertainty. Ground soil surveys are a way to reduce this uncertainty. However, ground surveys are time consuming and labor intensive. In this study, an inverse method for estimating mean and standard deviation of soil PSD from observed soil moisture is proposed and applied to Throughfall Displacement Experiment sites in Walker Branch Watershed in eastern Tennessee. This method is based on the relationship between spatial mean and standard deviation of soil moisture. The results indicate that the suggested method is feasible and has potential for retrieving soil PSD information globally from remotely sensed soil moisture data.

  14. 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

  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. 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.

  17. Studies of the observed and theoretical variations of atmospheric ozone

    NASA Technical Reports Server (NTRS)

    London, Julius

    1990-01-01

    The four related topics covered include: (1) distributions of total and upper atmospheric ozone and their time and space variations; (2) observed and theoretical models of the quasi-biennial oscillation (QBO) ozone variation; (3) radiative processes in the upper atmosphere; and (4) relations between ozone and solar variations. The results of these studies are presented. They come from twenty-three published papers.

  18. 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…

  19. Mixing and administration times of bypassing agents: observations from the Dosing Observational Study in Hemophilia (DOSE)

    PubMed Central

    Maahs, Jennifer; Donkin, Jennifer; Recht, Michael; Cooper, David L

    2014-01-01

    DOSE (Dosing Observational Study in Hemophilia) was a prospective, observational diary study designed to evaluate the use of bypassing agents in patients prescribed recombinant activated factor VII (rFVIIa) as first-line treatment in the home setting. Patients with congenital hemophilia with inhibitors and caregivers participated, and as part of the study, the time spent preparing and administering product was recorded for bypassing agent (BPA) infusions. The aim of this manuscript is to present the results of the analysis of the time spent preparing and administering a single dose of either rFVIIa or plasma-derived activated prothrombin complex concentrate (pd-aPCC). Diaries were completed for 18 adult patients and 19 caregivers of 21 children with 176 BPA-treated bleeding episodes and 1,350 BPA infusions (1,270 rFVIIa, 80 pd-aPCC). The median preparation and administration times were 5.0 minutes and 5.0 minutes for rFVIIa and 29.0 minutes and 24.5 minutes for pd-aPCC, respectively. Preparation and administration times were significantly shorter with rFVIIa than pd-aPCC (P<0.0001). The significantly shorter combined preparation and administration time of rFVIIa, taking into consideration the faster-than-recommended aPCC infusion rates, suggests that rFVIIa permits a rapid and safe initiation of treatment once a bleeding episode is identified and a decision is made to treat at home. PMID:25187744

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

    DOE PAGESBeta

    Wang, X.; Heald, C. L.; Sedlacek, A.; de Sa, S. S.; Martin, S. T.; Alexander, M. L.; Watson, T. B.; Aiken, A. C.; Springston, S. R.; Artaxo, P.

    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 m2/g for OA-MAC at 440nm. Using the combination of AERONET and OMI UV absorption observations we estimate that the AAE388/440nm 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

  1. Method for Determining the Radius Vector for a Planet from Two Observations of Position

    ERIC Educational Resources Information Center

    Gainer, Michael Kizinski

    1977-01-01

    Presents a method for determining the approximate radius vector of a planet or asteroid from two closely separated observation positions, using mathematics suitable for lower division college students. (MLH)

  2. Observer study to evaluate the simulation of mammographic calcification clusters

    NASA Astrophysics Data System (ADS)

    Sousa, Maria A. Z.; Marcomini, Karem D.; Bakic, Predrag R.; Maidment, Andrew D. A.; Schiabel, Homero

    2016-03-01

    Numerous breast phantoms have been developed to be as realistic as possible to ensure the accuracy of image quality analysis, covering a greater range of applications. In this study, we simulated three different densities of the breast parenchyma using paraffin gel, acrylic plates and PVC films. Hydroxyapatite was used to simulate calcification clusters. From the images acquired with a GE Senographe DR 2000D mammography system, we selected 68 regions of interest (ROIs) with and 68 without a simulated calcification cluster. To validate the phantom simulation, we selected 136 ROIs from the University of South Florida's Digital Database for Screening Mammography (DDSM). Seven trained observers performed two observer experiments by using a high-resolution monitor Barco mod. E-3620. In the first experiment, the observers had to distinguish between real or phantom ROIs (with and without calcification). In the second one, the observers had to indicate the ROI with calcifications between a pair of ROIs. Results from our study show that the hydroxyapatite calcifications had poor contrast in the simulated breast parenchyma, thus observers had more difficulty in identifying the presence of calcification clusters in phantom images. Preliminary analysis of the power spectrum was conducted to investigate the radiographic density and the contrast thresholds for calcification detection. The values obtained for the power spectrum exponent (β) were comparable with those found in the literature.

  3. Videotaped recording as a method of participant observation in psychiatric nursing research.

    PubMed

    Latvala, E; Vuokila-Oikkonen, P; Janhonen, S

    2000-05-01

    This paper describes videotaped recording as a data collection method when conducting participant observation in a psychiatric nursing study. The videotaped episodes were part of the daily life of psychiatric nursing in a hospital environment. The advantages and limitations of using videotaped recording in nursing research will be discussed. This paper is based on two studies. The data consisted of 21 videotaped episodes of nursing report sessions or interdisciplinary team meetings in the psychiatric clinic of a university hospital. The participants consisted of patients, their significant others, nurses, doctors, social workers and physiotherapists. All videotaped material was transcribed verbatim. An essential advantage of videotaping is that most potentially useful interaction and behaviour can be captured. The advantage in terms of the credibility of videotaping was that the investigator was able to review the same videotaped situations again and again. Videotaped material is rich and provides several possibilities for analysing the data. In these studies data and source triangulation enabled the researchers to reduce personal influence on the results. The investigator must also be aware of the limitations concerning this method. The most essential limitations are mechanical problems and the influence of videotaping on behaviour. Careful ethical considerations are important concerning personal privacy, informed consent and respect for the self-determination of psychiatric patients.

  4. An Observational Method in the Foreign Language Classroom: A Closer Look at Interaction Analysis

    ERIC Educational Resources Information Center

    Bailey, Leona G.

    1975-01-01

    This paper analyzes both Flanders' and the Foreign Language Interaction (FLint) methods of classroom observation and concludes that both systems are deficient in accuracy, reliability and practicality. Observing, recording and decision-making difficulties are inherent, and system complexities and teacher biases add to the problems. (CHK)

  5. 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.

  6. 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

  7. Transurethral resection syndrome in elderly patients: a retrospective observational study

    PubMed Central

    2014-01-01

    Background Transurethral resection of the prostate (TURP) involves the risk of transurethral resection (TUR) syndrome owing to hyponatremia. Irrigation fluid type, duration of operation, and weight of resected mass have been evaluated as risk factors for TUR syndrome. The purpose of the present study was to identify risk factors related to TUR syndrome in the elderly. Methods After obtaining approval from the Institutional Review Board, data on all elderly males (aged 70 years and older) who underwent TURP under regional anesthesia over a 6-year period at our institution were retrospectively reviewed. TUR syndrome was defined as evidence of a central nervous system disturbance such as nausea, vomiting, restlessness, confusion, or even coma with a circulatory abnormality both intra- and post-operatively. Patients were divided into two groups, positive and negative, for the occurrence of the syndrome. Data such as previous medical history, preoperative and postoperative serum data, weight of resected mass, duration of operation, irrigation fluid drainage technique, anesthetic technique, operative infusion and transfusion volume, and neurological symptoms were collected. Only observational variables with p < 0.05 on univariate analyses were included in the multivariate logistic regression model to ascertain their independent effects on TUR syndrome. Results Of the 98 patients studied, 23 had TUR syndrome (23.5%, 95% confidence interval [CI] 14.9–32.0%). Multivariate regression analysis revealed that volume of plasma substitute ≥ 500 ml (odds ratio [OR] 14.7, 95% CI 2.9–74.5), continuous irrigation through a suprapubic cystostomy (OR 4.7, 95% CI 1.3–16.7), and weight of resected mass > 45 g (OR 4.1, 95% CI 1.2–14.7) were associated with significantly increased risks for TUR syndrome (Hosmer-Lemeshow test, p = 0.94, accuracy 84.7%). Conclusions These results suggest that the use of a plasma substitute and continuous irrigation through a

  8. Deriving brown carbon from multiwavelength absorption measurements: method and application to AERONET and Aethalometer observations

    NASA Astrophysics Data System (ADS)

    Wang, Xuan; Heald, Colette L.; Sedlacek, Arthur J.; de Sá, Suzane S.; Martin, Scot T.; Lizabeth Alexander, M.; Watson, Thomas B.; Aiken, Allison C.; Springston, Stephen R.; Artaxo, Paulo

    2016-10-01

    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 modeling 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 regarding the spectral dependence of BC that are often violated in the ambient atmosphere. Here we develop a new AAE method which improves upon previous approaches by using the information from the wavelength-dependent measurements themselves and by allowing for an atmospherically relevant range of BC properties, rather than fixing these at a single assumed value. We note that constraints on BC optical properties and mixing state would help further improve this method. We apply this method to multiwavelength 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 up to 40 % of the seasonally averaged absorption at 440 nm. We find that the mass absorption coefficient of OA (OA-MAC) is positively correlated with the BC / OA mass ratio. Based on the variability in BC properties and BC / OA emission ratio, we estimate a range of 0.05-1.5 m2 g-1 for OA-MAC at 440 nm. Using the combination of AERONET and OMI UV absorption observations we estimate that the AAE388/440 nm for BrC is generally ˜ 4 worldwide, with a smaller value in Europe (< 2). Our analyses of observations at two surface sites (Cape Cod, to the southeast of Boston, and the GoAmazon2014/5 T3 site, to the west of

  9. 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;…

  10. Developing best practices teaching procedures for skinfold assessment: observational examination using the Think Aloud method.

    PubMed

    Holmstrup, Michael E; Verba, Steven D; Lynn, Jeffrey S

    2015-12-01

    Skinfold assessment is valid and economical; however, it has a steep learning curve, and many programs only include one exposure to the technique. Increasing the number of exposures to skinfold assessment within an undergraduate curriculum would likely increase skill proficiency. The present study combined observational and Think Aloud methodologies to quantify procedural and cognitive characteristics of skinfold assessment. It was hypothesized that 1) increased curricular exposure to skinfold assessment would improve proficiency and 2) the combination of an observational and Think Aloud analysis would provide quantifiable areas of emphasis for instructing skinfold assessment. Seventy-five undergraduates with varied curricular exposure performed a seven-site skinfold assessment on a test subject while expressing their thoughts aloud. A trained practitioner recorded procedural observations, with transcripts generated from audio recordings to capture cognitive information. Skinfold measurements were compared with a criterion value, and bias scores were generated. Participants whose total bias fell within ±3.5% of the criterion value were proficient, with the remainder nonproficient. An independent-samples t-test was used to compare procedural and cognitive observations across experience and proficiency groups. Additional curricular exposure improved performance of skinfold assessment in areas such as the measurement of specific sites (e.g., chest, abdomen, and thigh) and procedural (e.g., landmark identification) and cognitive skills (e.g., complete site explanation). Furthermore, the Think Aloud method is a valuable tool for determining curricular strengths and weaknesses with skinfold assessment and as a pedagogical tool for individual instruction and feedback in the classroom. PMID:26628650

  11. Developing best practices teaching procedures for skinfold assessment: observational examination using the Think Aloud method.

    PubMed

    Holmstrup, Michael E; Verba, Steven D; Lynn, Jeffrey S

    2015-12-01

    Skinfold assessment is valid and economical; however, it has a steep learning curve, and many programs only include one exposure to the technique. Increasing the number of exposures to skinfold assessment within an undergraduate curriculum would likely increase skill proficiency. The present study combined observational and Think Aloud methodologies to quantify procedural and cognitive characteristics of skinfold assessment. It was hypothesized that 1) increased curricular exposure to skinfold assessment would improve proficiency and 2) the combination of an observational and Think Aloud analysis would provide quantifiable areas of emphasis for instructing skinfold assessment. Seventy-five undergraduates with varied curricular exposure performed a seven-site skinfold assessment on a test subject while expressing their thoughts aloud. A trained practitioner recorded procedural observations, with transcripts generated from audio recordings to capture cognitive information. Skinfold measurements were compared with a criterion value, and bias scores were generated. Participants whose total bias fell within ±3.5% of the criterion value were proficient, with the remainder nonproficient. An independent-samples t-test was used to compare procedural and cognitive observations across experience and proficiency groups. Additional curricular exposure improved performance of skinfold assessment in areas such as the measurement of specific sites (e.g., chest, abdomen, and thigh) and procedural (e.g., landmark identification) and cognitive skills (e.g., complete site explanation). Furthermore, the Think Aloud method is a valuable tool for determining curricular strengths and weaknesses with skinfold assessment and as a pedagogical tool for individual instruction and feedback in the classroom.

  12. Critical study of observation of the sternal end of the right 4th rib.

    PubMed

    Fanton, Laurent; Gustin, Marie-Paule; Paultre, Ulysse; Schrag, Bettina; Malicier, Daniel

    2010-03-01

    Studies of the method of estimating age at death by the 4th rib exclusively concerned the phase method without fundamentally challenging the method as such. The present study analyzed observation of the variables on which the Işcan method is based. Ten observers made two assessments of the stage of pit depth, pit shape, rim and wall configurations of 59 right 4th ribs harvested from males (mean age: 49 years; range: 47-94 years). Observation showed poor reproducibility and repeatability for all three variables (Wilcoxon test, kappa-coefficient). Analysis of problem ribs revealed difficulty in measuring and imprecision in describing pit depth and failure to take account of continual aging for the other two variables. Despite these results, Işcan's variables provide objective information on age at death. It is recommended that the method be improved by better description of the variables and use of multivariate statistical analysis.

  13. Fog forecasting: ``old fashioned'' semi-empirical methods from radio sounding observations versus ``modern'' numerical models

    NASA Astrophysics Data System (ADS)

    Holtslag, M. C.; Steeneveld, G. J.; Holtslag, A. A. M.

    2010-07-01

    Fog forecasting is a very challenging task due to the local and small-scale nature of the relevant physical processes and land surface heterogeneities. Despite the many research efforts, numerical models remain to have difficulties with fog forecasting, and forecast skill from direct model output is relatively poor. In order to put the progress of fog forecasting in the last decades into a historical perspective, we compare the fog forecasting skill of a semi-empirical method based on radio sounding observations (developed in the 60s and 70s) with the forecasting skill of a state-of-the-art numerical weather prediction model (MM5) for The Netherlands. The semi-empirical method under investigation, the Fog Stability Index, depends solely on the temperature difference between the surface and 850 hPa, the surface dew point depression and the wind speed at 850 hPa, and a threshold value to indicate the probability of fog in the coming hours. Using the critical success index (CSI) as a criterion for forecast quality, we find that the Fog Stability Index is a rather successful predictor for fog, with similar performance as MM5. The FSI could even been optimized for different observational stations in the Netherlands. Also, it appears that adding the 10 m wind as a predictor did not increase the CSI score for all stations. The results of the current study clearly indicate that the current state of knowledge requires improvement of the physical insight in different physical processes in order to beat simple semi-empirical methods.

  14. Determining Best Method for Estimating Observed Level of Maximum Convective Detrainment based on Radar Reflectivity

    NASA Astrophysics Data System (ADS)

    Carletta, N.; Mullendore, G. L.; Xi, B.; Feng, Z.; Dong, X.

    2013-12-01

    Convective mass transport is the transport of mass from near the surface up to the upper troposphere and lower stratosphere (UTLS) by a deep convective updraft. This transport can alter the chemical makeup and water vapor balance of the UTLS, which can affect cloud formation and the radiative properties of the atmosphere. It is therefore important to understand the exact altitudes at which mass is detrained from convection. The purpose of this study is to improve upon previously published methodologies for estimating the level of maximum detrainment (LMD) within convection using data from individual radars. Three methods were used to identify the LMD and validated against dual-Doppler derived vertical mass divergence fields. The best method for locating the LMD was determined to be the method that uses a horizontal reflectivity texture-based technique to determine convective cores and a multi-layer echo identification to determine anvil locations. The methodology was found to work in many but not all cases. The methodology works best when applied to convective systems with mature updrafts, and is most accurate with convective lines and single cells. A time lag is present in the reflectivity based LMD compared to the vertical mass divergence based LMD because the reflectivity method is dependent on anvil growth. This methodology was then applied to archived NEXRAD 3D mosaic radar data. The regions of analysis were chosen to coincide with the observation regions for the Deep Convective Clouds and Chemistry Experiment (DC3): the Colorado Foothills, Southern Plains (OK/TX), and Southeast US (AL). These three regions provide a wide variety of convection. The dates analyzed were from May and June of 2012 so the results can be compared to future DC3 studies. The variability of detrainment heights for the early convective season for these different geographical regions will be presented.

  15. Development and evaluation of an observational method for assessing repetition in hand tasks.

    PubMed

    Latko, W A; Armstrong, T J; Foulke, J A; Herrin, G D; Rabourn, R A; Ulin, S S

    1997-04-01

    Several physical stressors, including repetitive, sustained, and forceful exertions, awkward postures, localized mechanical stress, highly dynamic movements, exposures to low temperatures, and vibration have been linked to increased risk of work-related musculoskeletal disorders. Repetitive exertions have been among the most widely studied of these stressors, but there is no single metric for assessing exposure to repetitive work. A new methodology enables repetitive hand activity to be rated based on observable characteristics of manual work. This method uses a series of 10-cm visual-analog scales with verbal anchors and benchmark examples. Ratings for repetition reflect both the dynamic aspect of hand movements and the amount of recovery or idle hand time. Trained job analysis experts rate the jobs individually and then agree on ratings. For a group of 33 jobs, repetition ratings using this system were compared to measurements of recovery time within the cycle, exertion counts, and cycle time. Amount of recovery time within the job cycle was found to be significantly correlated with the analysis ratings (r2 = 0.58), as were the number of exertions per second (r2 = 0.53). Cycle time was not related to the analyst ratings. Repeated analyses using the new method were performed 1 1/2 to 2 years apart on the same jobs with the same group of raters. Ratings for repetition differed less than 1 point (on the 10-cm scale), on average, among the different sessions. These results indicate that the method is sensitive to exertion level and recovery time, and that the decision criteria and benchmark examples allow for a consistent application of these methods over a period of time. This method of rating repetition can be combined with similar scales for other physical stressors. PMID:9115085

  16. 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.

  17. An Observational Method for Verifying Trends in Urban CO2 Emissions Using Continuous Measurements and High Resolution Meteorology (Invited)

    NASA Astrophysics Data System (ADS)

    Wofsy, S. C.; McKain, K.; Eluszkiewicz, J.; Nehrkorn, T.; Pataki, D. E.; Ehleringer, J.

    2010-12-01

    Nations of the world are attempting to reach international and domestic agreements to limit greenhouse gas emissions. Participants will demonstrate their compliance to such commitments with self-reported emissions estimates based largely on measurements of behavior and generalized conversion factors. Atmospheric observations are the only source of information that will allow reported emissions to be independently and directly verified. Testing of observation-based verification methods is required to establish current capabilities, identify and prioritize areas for improvement, and ensure that policy goals are verifiable. In particular, observations made in major source regions, such as cities, could provide a great deal of information about trends and patterns in anthropogenic emissions with relatively modest investment. This study presents an inaugural effort to estimate carbon dioxide (CO2) emissions from a city using atmospheric measurements. We have developed an observation-modeling framework to track changes in urban emissions, which, in addition to the observations, utilizes an atmospheric transport model and a prior emissions estimates. We have conducted a pilot study of the method using an existing longterm dataset of CO2 observations from Salt Lake City, Utah. Model-simulated CO2 concentrations track diurnal and synoptic patterns in observations reasonably well, although areas for improvement are evident. The modeling framework tends to underestimate observed CO2 enhancements, especially at night, which could be due to underestimated emissions and/or to excessive ventilation in the modeled meteorology. Despite some deficiencies, modeled and observed CO2 values are quantitatively and systematically related and application of a scaling factor to previously estimated emissions improves the match between modeled and observed values. This pilot-study presents a generalized, albeit provisional, method for using urban atmospheric greenhouse gas observations to

  18. Solar Flare Predictions Using Time Series of SDO/HMI Observations and Machine Learning Methods

    NASA Astrophysics Data System (ADS)

    Ilonidis, Stathis; Bobra, Monica; Couvidat, Sebastien

    2015-08-01

    Solar active regions are dynamic systems that can rapidly evolve in time and produce flare eruptions. The temporal evolution of an active region can provide important information about its potential to produce major flares. In this study, we build a flare forecasting model using supervised machine learning methods and time series of SDO/HMI data for all the flaring regions with magnitude M1.0 or higher that have been observed with HMI and several thousand non-flaring regions. We define and compute hundreds of features that characterize the temporal evolution of physical properties related to the size, non-potentiality, and complexity of the active region, as well as its flaring history, for several days before the flare eruption. Using these features, we implement and test the performance of several machine learning algorithms, including support vector machines, neural networks, decision trees, discriminant analysis, and others. We also apply feature selection algorithms that aim to discard features with low predictive power and improve the performance of the machine learning methods. Our results show that support vector machines provide the best forecasts for the next 24 hours, achieving a True Skill Statistic of 0.923, an accuracy of 0.985, and a Heidke skill score of 0.861, which improve the scores obtained by Bobra and Couvidat (2015). The results of this study contribute to the development of a more reliable and fully automated data-driven flare forecasting system.

  19. Intra-observer reliability of Prechtl’s method for the qualitative assessment of general movements in Taiwanese infants

    PubMed Central

    Yeh, Kuo-Kuang; Liu, Wen-Yu; Wong, Alice May-Kuen; Chung, Chia-Ying; Lien, Reyin; Chuang, Yu-Fen

    2016-01-01

    [Purpose] The aim of this study was to examine the intra-observer reliability for Prechtl’s General Movements Assessment in Taiwanese infants. This includes the global General Movements Assessment, the Optimality List for Preterm General Movements and Writhing Movements, and the Assessment of Motor Repertoire—3 to 5 Months. [Subjects and Methods] Fifty-nine videos of 37 infants were observed and rated by one physical therapist twice. [Results] The intra-observer reliability ranged from good to very good for the global General Movements Assessment. The overall intra-observer reliabilities for the total score of the Optimality List from preterm up to postmenstrual age 46 weeks and the total score of the Assessment of Motor Repertoire for postmenstrual age 49 to 60 weeks were both good. [Conclusion] The results suggest that the intra-observer reliability of a certified physical therapist was satisfactory for Prechtl’s method in Taiwanese infants. PMID:27313378

  20. Intra-observer reliability of Prechtl's method for the qualitative assessment of general movements in Taiwanese infants.

    PubMed

    Yeh, Kuo-Kuang; Liu, Wen-Yu; Wong, Alice May-Kuen; Chung, Chia-Ying; Lien, Reyin; Chuang, Yu-Fen

    2016-05-01

    [Purpose] The aim of this study was to examine the intra-observer reliability for Prechtl's General Movements Assessment in Taiwanese infants. This includes the global General Movements Assessment, the Optimality List for Preterm General Movements and Writhing Movements, and the Assessment of Motor Repertoire-3 to 5 Months. [Subjects and Methods] Fifty-nine videos of 37 infants were observed and rated by one physical therapist twice. [Results] The intra-observer reliability ranged from good to very good for the global General Movements Assessment. The overall intra-observer reliabilities for the total score of the Optimality List from preterm up to postmenstrual age 46 weeks and the total score of the Assessment of Motor Repertoire for postmenstrual age 49 to 60 weeks were both good. [Conclusion] The results suggest that the intra-observer reliability of a certified physical therapist was satisfactory for Prechtl's method in Taiwanese infants. PMID:27313378

  1. 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

  2. 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.

  3. The new worlds observer: The astrophysics strategic mission concept study

    NASA Astrophysics Data System (ADS)

    Cash, W.

    2011-07-01

    We present some results of the Astrophysics Strategic Mission Concept Study for the New Worlds Observer (NWO). We show that the use of starshades is the most effective and affordable path to mapping and understanding our neighboring planetary systems, to opening the search for life outside our solar system, while serving the needs of the greater astronomy community. A starshade-based mission can be implemented immediately with a near term program of technology demonstration.

  4. Observational studies of reconnection in the solar corona

    SciTech Connect

    McKenzie, David E.

    2011-11-15

    In recent years, observational studies of the corona have shifted focus. Where they were once purely qualitative morphological explorations seeking to support the presence of reconnection, more investigations are providing empirical estimates of the physical conditions in the reconnecting corona. These studies are enabled and enhanced by orbiting telescopes with high angular and temporal resolution. In this article, some recent findings about the empirical quantities are reviewed, including recent estimates of the flux transferred in individual patchy reconnection episodes, the size distribution of post-reconnection flux tubes, and the energy released by the flux tubes as they shrink.

  5. A simple method to hide data loggers safely in observation wells.

    PubMed

    Lorenzen, Gunnar; Sprenger, Christoph; Pekdeger, Asaf

    2011-01-01

    Submersible data loggers are widely used for groundwater monitoring, but their application often runs the risk of hardware and data loss through vandalism or theft. During a field study in India, the authors of this article experienced that well locks attract the attention of unauthorized persons and do not provide secure protection in unattended areas. To minimize the risk of losing data loggers, a cheap and simple solution has been invented to hide the instruments and associated attachments below the ground surface, inside observation wells. It relies on attaching the logger to a length of small-diameter pipe that is submerged at the bottom of the well, instead of attaching it to the top of the well. The small-diameter pipe with the logger is connected to a small bottle containing a magnet that floats on the water surface of the well and can be recovered using another bottle also with a magnet. A logger that is concealed in this way is difficult to detect and access without knowledge of the method and adequate removal tools. The system was tested and successfully applied for monitoring shallow observation wells at three field sites in Greater Delhi, India. PMID:21087249

  6. A generic method to constrain the dark matter model parameters from Fermi observations of dwarf spheroids

    NASA Astrophysics Data System (ADS)

    Sming Tsai, Yue-Lin; Yuan, Qiang; Huang, Xiaoyuan

    2013-03-01

    Observation of γ-rays from dwarf galaxies is an effective way to search for particle dark matter. Using 4-year data of Fermi-LAT observations on a series of Milky Way satellites, we develop a general way to search for the signals from dark matter annihilation in such objects. Instead of giving prior information about the energy spectrum of dark matter annihilation, we bin the Fermi-LAT data into several energy bins and build a likelihood map in the ``energy bin - flux'' plane. The final likelihood of any spectrum can be easily derived through combining the likelihood of all the energy bins. It gives consistent result with that directly calculated using the Fermi Scientific Tool. This method is very efficient for the study of any specific dark matter models with γ-rays. We use the new likelihood map with Fermi-LAT 4 year data to fit the parameter space in three representative dark matter models: i) toy dark matter model, ii) effective dark matter operators, and iii) supersymmetric neutralino dark matter.

  7. A generic method to constrain the dark matter model parameters from Fermi observations of dwarf spheroids

    SciTech Connect

    Tsai, Yue-Lin Sming; Yuan, Qiang; Huang, Xiaoyuan E-mail: yuanq@ihep.ac.cn

    2013-03-01

    Observation of γ-rays from dwarf galaxies is an effective way to search for particle dark matter. Using 4-year data of Fermi-LAT observations on a series of Milky Way satellites, we develop a general way to search for the signals from dark matter annihilation in such objects. Instead of giving prior information about the energy spectrum of dark matter annihilation, we bin the Fermi-LAT data into several energy bins and build a likelihood map in the ''energy bin - flux'' plane. The final likelihood of any spectrum can be easily derived through combining the likelihood of all the energy bins. It gives consistent result with that directly calculated using the Fermi Scientific Tool. This method is very efficient for the study of any specific dark matter models with γ-rays. We use the new likelihood map with Fermi-LAT 4 year data to fit the parameter space in three representative dark matter models: i) toy dark matter model, ii) effective dark matter operators, and iii) supersymmetric neutralino dark matter.

  8. Determination of miscibility pressure by direct-observation method. Quarterly report, July 1-September 30, 1982

    SciTech Connect

    Wang, G.C.

    1982-01-01

    The objective of the project is to conduct laboratory tests to: (1) develop a method for determining miscibility pressure (MMP) through direct observation using a high pressure cell; and (2) determine feasibility of in-situ foam generation by visual observation and microphotographic technique. The project is organized and carried out in three major tasks, i.e., (1) MMP test; (2) high pressure sampling and chemical analysis; and (3) foam study and displacement test. The MMP test was 100% completed. The summary and results were presented in the last quarterly report. Chemical analysis using the HP5880-A was continued for SACROC crude oil at 76/sup 0/F and 150/sup 0/F and was also conducted for Rock Creek crude oil at 78/sup 0/F and 120/sup 0/F. Generally speaking, the changes of crude oil composition caused by CO/sub 2/ extraction are similar for both crude oils. During this reporting period, 29 displacements were performed for SACROC and Rock Creek crude soils. Results are discussed. 5 figures, 1 table.

  9. Studies of Tropical/Mid-Latitude Exchange Using UARS Observations

    NASA Technical Reports Server (NTRS)

    Avallone, Linnea

    2001-01-01

    At the time this proposal was submitted, recent publications had suggested an important role for transport of midlatitude air into the tropical lower stratosphere. Most of these studies had employed data that gave only a time-averaged picture, making it difficult to determine the nature of the transport processes responsible for the observed behavior. We proposed to analyze observations of long-lived trace gases, such as nitric acid, methane, nitrous oxide, and chlorofluorocarbons, made from the Upper Atmosphere Research Satellite, to investigate the seasonal behavior of mixing between the midlatitudes and tropics. We planned to construct probability distributions of the concentrations of these species over small altitude ranges and to compare them to expectations based on modeled mean concentrations and knowledge of instrument precision. Differences from expectation were to be analyzed with respect to meteorological parameters to determine whether wave activity may have induced apparent mixing.

  10. Combining geophysical methods for the observation of hydrological processes at the hillslope-scale

    NASA Astrophysics Data System (ADS)

    Martini, E.; Kögler, S.; Dierke, C.; Wollschlaeger, U.; Werban, U.; Behrens, T.; Schmidt, K.; Dietrich, P.; Zacharias, S.

    2012-12-01

    Knowledge of soil moisture dynamics beyond the point scale is of crucial importance e.g. for water management, hydrological studies, and for calibration and validation of soil water balance models. There is a clear need for robust and flexible monitoring technologies that are able to capture high resolution information over large areas. Fast, precise, and ideally in-situ, measurements may be obtained from geophysical surveys and distributed in-situ wireless soil moisture sensor networks. In the Harz Mountains (Central Germany), a 2.5 ha hillslope was chosen as study site, to be monitored using a wireless sensor network, consisting of Time-Domain Transmission (TDT) sensors, that are able to measure soil water content and, in addition, soil temperature. Along the hillslope, pedological features are correlated with topography, and lateral flows are expected to be a relevant component of the runoff process. The aim of the work is (i) to test and validate geophysical platforms at the small-catchment scale in terms of technological improvement and suitability for hydrological studies; (ii) to design spatially optimized monitoring strategies using geophysical methods; (iii) to validate soil moisture estimation using geophysical methods. For the preliminary study, a larger area of the catchment (144 ha in size) was investigated using three electromagnetical induction (EMI) sensors (EM38-DD, EM38-MK2 and EM31-MK2, Geonics Ltd., Canada) and a gamma-ray spectrometer (GF Instruments, Czech Republic).On the hillslope, time-lapse EMI data were collected, and measurements will be repeated in future surveys to monitor patterns in electrical conductivity of soil that are related to changes in the soil moisture content. Based on these data, a Latin Hypercube Sampling strategy (LHS) was applied to provide 30 sampling points for the soil moisture monitoring network. In order to intensify the observations at shorter distances, 10 additional points were added to the network. Before the

  11. A simple method of observation impact analysis for operational storm surge forecasting systems

    NASA Astrophysics Data System (ADS)

    Sumihar, Julius; Verlaan, Martin

    2016-04-01

    In this work, a simple method is developed for analyzing the impact of assimilating observations in improving forecast accuracy of a model. The method simply makes use of observation time series and the corresponding model output that are generated without data assimilation. These two time series are usually available in an operational database. The method is therefore easy to implement. Moreover, it can be used before actually implementing any data assimilation to the forecasting system. In this respect, it can be used as a tool for designing a data assimilation system, namely for searching for an optimal observing network. The method can also be used as a diagnostic tool, for example, for evaluating an existing operational data assimilation system to check if all observations are contributing positively to the forecast accuracy. The method has been validated with some twin experiments using a simple one-dimensional advection model as well as with an operational storm surge forecasting system based on the Dutch Continental Shelf model version 5 (DCSMv5). It has been applied for evaluating the impact of observations in the operational data assimilation system with DCSMv5 and for designing a data assimilation system for the new model DCSMv6. References: Verlaan, M. and J. Sumihar (2016), Observation impact analysis methods for storm surge forecasting systems, Ocean Dynamics, ODYN-D-15-00061R1 (in press) Zijl, F., J. Sumihar, and M. Verlaan (2015), Application of data assimilation for improved operational water level forecasting of the northwest European shelf and North Sea, Ocean Dynamics, 65, Issue 12, pp 1699-1716.

  12. A Multipurpose Method for Global Capacity Building in Using Earth Observations for Wetlands and Biodiversity

    NASA Astrophysics Data System (ADS)

    Bye, B. L.

    2015-12-01

    Monitoring and surveying biodiversity and wetlands involves the collection of vast amounts of data, most of which are Earth observations. Observations on the ground or from space and everything in between, across all time and spatial scales, represent precious information for our understanding and management of both biodiversity and wetlands. Cross-disciplinary problem solving and development of new tools are the most efficient ways to enhance our capabilities to monitor biodiversity and wetlands. To accomplish that, experts from different communities need to refresh and upgrade their knowledge of other field(s). An event based method that consists of both live active participation and the production of capacity building material for re-use in other settings, will be presented. The method includes using the vast global networks of international organizations representing the application areas as well as the field of Earth observations. An example from a cooperation between the Group of Earth Observations and the Ramsar Convention of Wetlands will be used to illustrate the method. Within the global Earth observation community there is a great potential for efficient capacity building, targeting both experts, decision-makers and the general public. The method presented is demonstrating one way of tapping into that potential.

  13. 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…

  14. 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.

  15. 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.

  16. 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

  17. 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.; Kossin, James P.; Lee, Hai-Tien; Loew, Alexander; Magnusdottir, Gudrun

    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.

  18. 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

  19. 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.

  20. Correlation studies on surface particle detection methods

    NASA Technical Reports Server (NTRS)

    Peterson, Ronald V.; White, James C.

    1988-01-01

    The accurate determination of dust levels on optical surfaces is necessary to assess sensor system performance. A comparison study was made on several particle measurement methods including those based on direct imaging and light scattering. The effectiveness of removing the particles from the surface prior to determining particle size distributions was also assessed. These studies revealed that some methods, especially those requiring particle removal before analysis, are subject to large systematic errors affecting particle size distributions. Thus, an understanding of the particle measurement methods employed is necessary before any surface cleanliness or obstruction value assignments are accepted as true representations of an optical surface contamination condition.

  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. Inter-Observer Reliability Assessments in Time Motion Studies: The Foundation for Meaningful Clinical Workflow Analysis

    PubMed Central

    Lopetegui, Marcelo A.; Bai, Shasha; Yen, Po-Yin; Lai, Albert; Embi, Peter; Payne, Philip R.O.

    2013-01-01

    Understanding clinical workflow is critical for researchers and healthcare decision makers. Current workflow studies tend to oversimplify and underrepresent the complexity of clinical workflow. Continuous observation time motion studies (TMS) could enhance clinical workflow studies by providing rich quantitative data required for in-depth workflow analyses. However, methodological inconsistencies have been reported in continuous observation TMS, potentially reducing the validity of TMS’ data and limiting their contribution to the general state of knowledge. We believe that a cornerstone in standardizing TMS is to ensure the reliability of the human observers. In this manuscript we review the approaches for inter-observer reliability assessment (IORA) in a representative sample of TMS focusing on clinical workflow. We found that IORA is an uncommon practice, inconsistently reported, and often uses methods that provide partial and overestimated measures of agreement. Since a comprehensive approach to IORA is yet to be proposed and validated, we provide initial recommendations for IORA reporting in continuous observation TMS. PMID:24551381

  3. 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.

  4. An observational study of entrainment rate in deep convection

    SciTech Connect

    Guo, Xiaohao; Lu, Chunsong; Zhao, Tianliang; Zhang, Guang Jun; Liu, Yangang

    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, 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.

  5. An observational study of entrainment rate in deep convection

    DOE PAGESBeta

    Guo, Xiaohao; Lu, Chunsong; Zhao, Tianliang; Zhang, Guang Jun; Liu, Yangang

    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

  6. 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

  7. Estimating transient climate response using consistent temperature reconstruction methods in models and observations

    NASA Astrophysics Data System (ADS)

    Richardson, M.; Cowtan, K.; Hawkins, E.; Stolpe, M.

    2015-12-01

    Observational temperature records such as HadCRUT4 typically have incomplete geographical coverage and blend air temperature over land with sea surface temperatures over ocean, in contrast to model output which is commonly reported as global air temperature. This complicates estimation of properties such as the transient climate response (TCR). Observation-based estimates of TCR have been made using energy-budget constraints applied to time series of historical radiative forcing and surface temperature changes, while model TCR is formally derived from simulations where CO2 increases at 1% per year. We perform a like-with-like comparison using three published energy-budget methods to derive modelled TCR from historical CMIP5 temperature series sampled in a manner consistent with HadCRUT4. Observation-based TCR estimates agree to within 0.12 K of the multi-model mean in each case and for 2 of the 3 energy-budget methods the observation-based TCR is higher than the multi-model mean. For one energy-budget method, using the HadCRUT4 blending method leads to a TCR underestimate of 0.3±0.1 K, relative to that estimated using global near-surface air temperatures.

  8. Spatiotemporal multiplexing method for visual field of view extension in holographic displays with naked eye observation

    NASA Astrophysics Data System (ADS)

    Finke, G.; Kujawińska, M.; Kozacki, T.; Zaperty, W.

    2016-09-01

    In this paper we propose a method which allows to overcome the basic functional problems in holographic displays with naked eye observation caused by delivering too small images visible in narrow viewing angles. The solution is based on combining the spatiotemporal multiplexing method with a 4f optical system. It enables to increase an aperture of a holographic display and extend the angular visual field of view. The applicability of the modified display is evidenced by Wigner distribution analysis of holographic imaging with spatiotemporal multiplexing method and by the experiments performed at the display demonstrator.

  9. 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)

  10. An observational study of post-asymptotic-giant-branch stars

    NASA Astrophysics Data System (ADS)

    Sahin, T.

    2008-05-01

    In this thesis, we present an LTE model atmosphere analyses of a group of early B-type postasymptotic giant branch (pAGB) stars. With initial masses ≤ 9M⊙, post-AGB stars form an important group of evolved stars and provide a unique opportunity to study stellar evolution almost on a human time-scale. Post-AGB stars have spectral types ranging from K to B and luminosities between 103 and 104L⊙. These objects ended their asymptotic giant branch (AGB) evolution phase with a period of strong mass loss (10-7 - 10-4M⊙ yr-1) and have been evolving from cooler to hotter temperatures at almost constant luminosity on a timescale of ˜ 104yr. B-type pAGB stars span a wide range in effective temperature (10 000 - 30 000K). Their expected surface gravities (log g ) and effective temperatures ( Teff ) coincide with those of B stars evolving from the main sequence. Therefore systematic observational analyses are required to distinguish these two groups. Furthermore, p! ost-AGB stars may be divided into four distinct groups based on their chemical composition. In this thesis, groups I and II represent post-AGB stars which are very metal deficient with C/O ≈ 1 and metal poor with C/O<1, when compared with the Sun, respectively. The question is whether hot pAGB stars belong to either of these four groups. Three further objectives included: 1. to discover whether post-AGB star have helium-normal or helium-rich photospheres. 2. the detection and measurement of s-process element abundances (e.g. Sr, Y, Ba, Hf). 3. to determine whether they show any anomaly in phosphorus abundance such as that seen in the extreme helium stars (EHes). High-resolution ´echelle spectra of several post-AGB stars were obtained at the AAT in 1999 and 2005 in order to study chemical composition, rotation velocities and other fundamental properties. Echelle spectra present many difficulties for data reduction, including the problems of order rectification and merging. To address these problems we

  11. Determination of miscibility pressure by direct observation method. Quarterly report, January 1-March 31, 1982

    SciTech Connect

    Wang, G. C.

    1982-01-01

    The objective of the project is to conduct laboratory tests to: (1) develop a method for determining MMP through direct observation using a high pressure cell; (2) determine feasibility of in-situ foam generation by visual observation and microphotographic technique. The project is presently organized and carried out in three major fronts: (1) MMP test; (2) high pressure sampling and chemical analysis; and (3) foam study and displacement test. The technical progress in each of these areas is discussed. The effects of temperature on MMP and appearance of CO/sub 2/-rich phase for four crude oils tested are plotted. The MMP is the pressure at which the CO/sub 2/-rich phase becomes miscible with CO/sub 2/ vapor. The results of gas chromatographic analysis for the four crude oils tested are presented. As previously stated the richness of C/sub 5/ to C/sub 20/ components is the key factor for determining the quality and stability of the miscible transition zone. The surfactant/CO/sub 2/ ratio relative to foam quality and foam quantity are presented in a table and also plotted. The plotted figures show: (1) the foam qualities increased as the surfactant rates are decreased; (2) at 75/sup 0/F, the foam quality increases as the pressure is decreased whereas the reverse is true for temperature at 120/sup 0/F; (3) foam generating rate increased with increasing surfactant/CO/sub 2/ ratio; (4) high temperatures tend to lower the rate and high pressures tend to increase the rate at 120/sup 0/F but to decrease at 75/sup 0/F; (5) foam quality was found to be affected more by surfactant/CO/sub 2/ ratio, and to a lesser degree by pressure and temperature. (ATT)

  12. Mucocutaneous manifestations of acquired hypoparathyroidism: An observational study.

    PubMed

    Sarkar, Somenath; Mondal, Modhuchanda; Das, Kapildev; Shrimal, Arpit

    2012-09-01

    Hypoparathyroidism is a disorder of calcium and phosphorus metabolism due to decreased secretion of parathyroid hormone. Hypoparathyroidism can be hereditary and acquired. Acquired hypoparathyroidism usually occurs following neck surgery (thyroid surgery or parathyroid surgery). Along with systemic manifestations, hypoparathyroidism produces some skin manifestations. Lack of study regarding mucocutaneous manifestations of acquired hypoparathyroidism prompted us to undertake this study. To evaluate the mucocutaneous manifestations of acquired hypoparathyroidism. An observational study done in a tertiary care hospital of Kolkata by comprehensive history taking, through clinical examination and relevant laboratory investigations. Twenty-one patients were included in the study. The commonest form of acquired hypoparathyroidism was neck surgery (thyroidectomy and parathyroidectomy operation). Mucocutaneous manifestations were present in 76.19% of patients. The most frequent mucocutaneous manifestation was found in the hairs like the loss of axillary hair (61.9%), loss of pubic hair (52.38%), coarsening of body hair (47.62%), and alopecia areata (9.52%). The nail changes noted were brittle and ridged nail, followed by onycholysis, onychosezia, and onychomedesis. The most common skin features were xerotic skin in 11 patients (52.38%), followed by pellagra-like skin pigmentation, pustular psoriasis and acne form eruption, bullous impetigo, etc. Mucosa was normal in all the cases excepting the one which showed oral candidiasis. PMID:23087872

  13. 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.

  14. [Economic assessment, a field between clinical research and observational studies].

    PubMed

    Launois, Robert

    2003-01-01

    Health technology assessments propose to study the differential impact of health interventions in a complex care system which is characterised by the multitude of individual behaviours and the diverse nature of the institutions involved. Current systems for data collection lend themselves poorly to this rigorous analysis of efficacy of treatments in the actual situations where they are used. Randomised trials endeavour to neutralise any parasitic interference which could compromise testing for a causal relationship between the treatment administered and the result obtained. Their methodology which establishes the term ceteris paribus in the principle of good practice lends itself poorly to an analysis of individual behaviour. Observational studies are start from actual treatment situations to describe them as reliably as possible. By definition, however, these assume that the natural course of events is not deviated by any intervention. The absence of an experimental plan increases the likelihood of bias and makes it more difficult to test for causal relationships. They lend themselves poorly to testing for incremental efficacy. The two instruments to be preferred are decisional analysis and quasi-experimental studies. Decisional analysis help to avoid the problems of external validity associated with randomised clinical trials by associating parameters which are extracted from data obtained from everyday practice. Quasi-experimental studies or pragmatic trials are based on the reality of behaviour of the prescriber and his/her patients; their impact on efficacy, quality of life social costs of the disease and of treatments may be identified under normal conditions of use. PMID:12609811

  15. Simulation Study Of Early Afterglows Observed With Swift

    NASA Astrophysics Data System (ADS)

    Nishikawa, Ken-Ichi; Hededal, C.; Hardee, P.; Mizuno, Y.; Fishman, G. J.

    2006-09-01

    A 3-D relativistic particle-in-cell code has been used to simulate the dynamics of forward and reverse shocks with thin and thick shells within the parameter constraints provided by present Swift observations and the present models of GRB emission. Our 3-D RPIC simulations have provided the dynamics of collisionless shocks in electron-ion and electron-positron plasmas with and without initial ambient magnetic fields and revealed the importance of ``jitter radiation'' with prompt and afterglow spectra due to the inhomogeneous magnetic fields generated by the Weibel instability. It is different from synchrotron radiation, which is usually assumed to be the dominant radiation process. We have investigated gamma-ray burst emissions from prompt, early, and late afterglows considering microscopic processes. Based on our previous investigation of the Weibel instability for each stage of evolution of ejecta propagating in the ISM, we have incorporated the plasma conditions (relativistic jets) with the density and composition of the plasmas, the magnetic field strength ($\\sigma$-values (the ratio of the electromagnetic energy flux to the particle energy flux)) and its direction, and the Lorentz factor for the different stages in prompt and afterglows. Systematic simulation studies of the relativistic collisionless shocks, associated particle acceleration, magnetic field generation and self-consistent radiation provide insight into undetermined issues in prompt and afterglows observed by Swift. Self-consistently calculated lightcurves, spectra, spectral evolutions, and polarization as function of viewing angle will be done to light a shed on recent new observations by Swift, in particular, X-ray flares, early steep decay, and shallow decay.

  16. Ragona-Scinà's (1847) Method for, and Observations of, Simultaneous Color Contrast.

    PubMed

    O'Shea, Robert P; Brini, Stefano; Wade, Nicholas J

    2016-03-01

    In 1847, Domenico Ragona-Scinà (1820-1892) published a method of optically superimposing images using an angled piece of colored glass. He showed that if one looks at a black, filled circle through the colored glass and superimposes on it the reflection from the glass of something white, the filled circle looks tinted with the complementary color of the background: simultaneous color contrast or contrast color. Although Ragona-Scinà's method and his observation have been cited into the 21st century, the former for its simplicity and the latter for its challenges to early theories of color vision, some errors have crept in and the phenomenon still lacks an agreed-on explanation. We provide some biographical information about Ragona-Scinà, set the method and the observation into their historical and theoretical contexts, and give a translation into English of Ragona-Scinà's Italian-language paper. PMID:27433327

  17. Ragona-Scinà’s (1847) Method for, and Observations of, Simultaneous Color Contrast

    PubMed Central

    Brini, Stefano; Wade, Nicholas J.

    2016-01-01

    In 1847, Domenico Ragona-Scinà (1820–1892) published a method of optically superimposing images using an angled piece of colored glass. He showed that if one looks at a black, filled circle through the colored glass and superimposes on it the reflection from the glass of something white, the filled circle looks tinted with the complementary color of the background: simultaneous color contrast or contrast color. Although Ragona-Scinà’s method and his observation have been cited into the 21st century, the former for its simplicity and the latter for its challenges to early theories of color vision, some errors have crept in and the phenomenon still lacks an agreed-on explanation. We provide some biographical information about Ragona-Scinà, set the method and the observation into their historical and theoretical contexts, and give a translation into English of Ragona-Scinà’s Italian-language paper. PMID:27433327

  18. Complementary methods of system usability evaluation: surveys and observations during software design and development cycles.

    PubMed

    Horsky, Jan; McColgan, Kerry; Pang, Justine E; Melnikas, Andrea J; Linder, Jeffrey A; Schnipper, Jeffrey L; Middleton, Blackford

    2010-10-01

    Poor usability of clinical information systems delays their adoption by clinicians and limits potential improvements to the efficiency and safety of care. Recurring usability evaluations are therefore, integral to the system design process. We compared four methods employed during the development of outpatient clinical documentation software: clinician email response, online survey, observations and interviews. Results suggest that no single method identifies all or most problems. Rather, each approach is optimal for evaluations at a different stage of design and characterizes different usability aspect. Email responses elicited from clinicians and surveys report mostly technical, biomedical, terminology and control problems and are most effective when a working prototype has been completed. Observations of clinical work and interviews inform conceptual and workflow-related problems and are best performed early in the cycle. Appropriate use of these methods consistently during development may significantly improve system usability and contribute to higher adoption rates among clinicians and to improved quality of care. PMID:20546936

  19. 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. PMID:27300186

  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. PMID:27328098

  1. [Observational study of atmospheric HONO in summer of Beijing].

    PubMed

    Zhu, Yan-Wu; Liu, Wen-Qing; Xie, Pin-Hua; Dou, Ke; Liu, Shi-Sheng; Si, Fu-Qi; Li, Su-Wen; Qin, Min

    2009-06-15

    The concentration of HONO, NO2, O3 and other atmospheric pollutants were observed continuously by using differential optical absorption spectroscopy (DOAS) from 2007-08-14 to 2007-08-24 in Beijing, China. Diurnal variation characteristics of HONO and NO2 were analyzed. The HONO levels originated from the nocturnal direct emission were discussed. And the correlation between the heterogeneous formation of HONO and its related factors (BC, RH, and so on) was studied. The results showed that HONO had two peaks at about 01:00 and 06:00, respectively, while two peaks of NO2 concentrations appeared at about 01:00 and 07:00. The highest HONO(em)/HONO ratio of 31.3% was observed at about 20:00 between 19:00 to 07:00, and the average ratio was 15%. Good correlation of HONO(corr)/NO2 ratio with BC and RH at night was obtained. The correlation suggested that heterogeneous NO2 to HONO conversion processes may occur on BC surfaces by reaction with absorption water, and the average nighttime conversion frequency from NO2 into HONO (HONO/NO2) was calculated about 0.8% x h(-1). At the same time, the results showed that heterogeneous formation of HONO was increased with RH and inhibited at RH > 80%, and the hypothesis was further supported by detailed analysis of selected case. PMID:19662832

  2. Recommendations for observational studies of comorbidity in multiple sclerosis

    PubMed Central

    Miller, Aaron; Sormani, Maria Pia; Thompson, Alan; Waubant, Emmanuelle; Trojano, Maria; O'Connor, Paul; Fiest, Kirsten; Reider, Nadia; Reingold, Stephen; Cohen, Jeffrey A.

    2016-01-01

    Objective: To reach consensus about the most relevant comorbidities to study in multiple sclerosis (MS) with respect to incidence, prevalence, and effect on outcomes; review datasets that may support studies of comorbidity in MS; and identify MS outcomes that should be prioritized in such studies. Methods: We held an international workshop to meet these objectives, informed by a systematic review of the incidence and prevalence of comorbidity in MS, and an international survey regarding research priorities for comorbidity. Results: We recommend establishing age- and sex-specific incidence and prevalence estimates for 5 comorbidities (depression, anxiety, hypertension, hyperlipidemia, and diabetes); evaluating the effect of 7 comorbidities (depression, anxiety, hypertension, diabetes, hyperlipidemia, chronic lung disease, and autoimmune diseases) on disability, quality of life, brain atrophy and other imaging parameters, health care utilization, employment, and mortality, including age, sex, race/ethnicity, socioeconomic status, and disease duration as potential confounders; harmonizing study designs across jurisdictions; and conducting such studies worldwide. Ultimately, clinical trials of treating comorbidity in MS are needed. Conclusion: Our recommendations will help address knowledge gaps regarding the incidence, prevalence, and effect of comorbidity on outcomes in MS. PMID:26865523

  3. Method for residual household waste composition studies.

    PubMed

    Sahimaa, Olli; Hupponen, Mari; Horttanainen, Mika; Sorvari, Jaana

    2015-12-01

    The rising awareness of decreasing natural resources has brought forward the idea of a circular economy and resource efficiency in Europe. As a part of this movement, European countries have identified the need to monitor residual waste flows in order to make recycling more efficient. In Finland, studies on the composition of residual household waste have mostly been conducted using different methods, which makes the comparison of the results difficult. The aim of this study was to develop a reliable method for residual household waste composition studies. First, a literature review on European study methods was performed. Also, 19 Finnish waste composition studies were compared in order to identify the shortcomings of the current Finnish residual household waste composition data. Moreover, the information needs of different waste management authorities concerning residual household waste were studied through a survey and personal interviews. Stratification, sampling, the classification of fractions and statistical analysis were identified as the key factors in a residual household waste composition study. The area studied should be divided into non-overlapping strata in order to decrease the heterogeneity of waste and enable comparisons between different waste producers. A minimum of six subsamples, each 100 kg, from each stratum should be sorted. Confidence intervals for each waste category should be determined in order to evaluate the applicability of the results. A new three-level classification system was created based on Finnish stakeholders' information needs and compared to four other European waste composition study classifications.

  4. Method for residual household waste composition studies.

    PubMed

    Sahimaa, Olli; Hupponen, Mari; Horttanainen, Mika; Sorvari, Jaana

    2015-12-01

    The rising awareness of decreasing natural resources has brought forward the idea of a circular economy and resource efficiency in Europe. As a part of this movement, European countries have identified the need to monitor residual waste flows in order to make recycling more efficient. In Finland, studies on the composition of residual household waste have mostly been conducted using different methods, which makes the comparison of the results difficult. The aim of this study was to develop a reliable method for residual household waste composition studies. First, a literature review on European study methods was performed. Also, 19 Finnish waste composition studies were compared in order to identify the shortcomings of the current Finnish residual household waste composition data. Moreover, the information needs of different waste management authorities concerning residual household waste were studied through a survey and personal interviews. Stratification, sampling, the classification of fractions and statistical analysis were identified as the key factors in a residual household waste composition study. The area studied should be divided into non-overlapping strata in order to decrease the heterogeneity of waste and enable comparisons between different waste producers. A minimum of six subsamples, each 100 kg, from each stratum should be sorted. Confidence intervals for each waste category should be determined in order to evaluate the applicability of the results. A new three-level classification system was created based on Finnish stakeholders' information needs and compared to four other European waste composition study classifications. PMID:26337965

  5. Marital communication in eating disorder patients: a controlled observational study.

    PubMed

    Van den Broucke, S; Vandereycken, W; Vertommen, H

    1995-01-01

    In order to investigate the communication between 21 eating disorder (ED) patients and their husbands, an observational study was carried out using two matched control groups of 21 maritally distressed (MD) and 21 nondistressed (ND) couples. During some discussion tasks the interaction was videotaped and the (verbal and nonverbal) communication skills were rated afterwards according to the Kategoriensystem für Partnerschaftliche Interaktion (KPI) coding system. Unexpectedly, compared with the control groups ED couples do not show a greater disequilibrium (between patient and husband) in the emission rate of positive and negative messages. Also striking is the generally higher degree of self-disclosure in ED couples than in ND couples, but this may reflect their experience of distress. Overall and most importantly, ED couples appear to lack some of the ND couples' skills of constructive communication, but manage to avoid the destructive communication style of MD couples.

  6. 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.; Hipskind, R. Stephen (Technical Monitor)

    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.

  7. 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.

  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. MAGDAS/CPMN Observations for Space Weather Study

    NASA Astrophysics Data System (ADS)

    Yumoto, K.

    2004-05-01

    An objective of the STP (nderline{S}olar nderline{T}errestrial nderline{P}hysics) researches is to support human activities in the geospace in the twenty-first century from an aspect of fundamental study. In order to understand the Sun-Earth system and effects to human lives, the international LWS (nderline{L}iving nderline{W}ith nderline{S}tar) and CAWSES (nderline{C}limate nderline{a}nd nderline{W}eather of nderline{S}un-nderline{E}arth nderline{S}ystem) programs start from 2004. The objective of CAWSES-WG 2 & 3 in Japan for the region from the solar surface through the solar wind, the magnetosphere, the ionosphere, and the thermosphere, to the atmosphere is a creation of new physics; (1) couplings of the complex and composite systems and (2) macro-and-micro-scale couplings in the Solar-Terrestrial system. The goals of CAWSES-WG 2 & 3 in Japan are to construct space weather stations (for observations) and modeling stations (for simulation/empirical modeling) during the period (2004-2008) of the international CAWSES program. Japanese STP groups will coordinate a research network to reach these goals for the space weather study. In order to study the complexity in the solar wind-magnetosphere-ionosphere-Earth's surface system, the nderline{S}pace nderline{E}nvironment nderline{R}esearch nderline{C}enter (SERC), Kyushu University, Fukuoka, Japan will carry out coordinated ground-based network observations for space weather studies, in cooperation with about 30 organizations in the world during the international CAWSES period (2004-2008). In the present paper, we will introduce a real-time nderline{MAC}netic nderline{D}ata nderline{A}cquisition nderline{S}ystem of nderline{C}ircumpan nderline{P}acific nderline{M}agnetometer nderline{N}etwork, i.e. MAGDAS/CPMN system in Kyushu University. By using this system, we will conduct the real-time monitoring and modeling of (1) the global 3-dimensional current system and (2) the plasma density variations for space weather

  10. Shaping the Future: Writing up the Method on Qualitative Studies.

    ERIC Educational Resources Information Center

    Rocco, Tonette S.

    2003-01-01

    Observations on qualitative manuscripts submitted for publication identified problem areas: organization and format, relationship of concept and method, methodological issues (study type, conceptual framework, sample, data collection/analysis, integrity, data management), discussion, and data presentation. Recommendations for improving quality of…

  11. 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.

  12. Evidence of clinical competence by simulation, a hermeneutical observational study.

    PubMed

    Lejonqvist, Gun-Britt; Eriksson, Katie; Meretoja, Riitta

    2016-03-01

    Making the transition from theory to practise easier in nursing education through simulation is widely implemented all over the world, and there is research evidence of the positive effects of simulation. The pre-understanding for this study is based on a definition of clinical competence as encountering, knowing, performing, maturing and developing, and the hypothesis is that these categories should appear in simulated situations. The aim of the study was to explore the forms and expressions of clinical competence in simulated situations and furthermore to explore if and how clinical competence could be developed by simulation. An observational hermeneutic study with a hypothetic-deductive approach was used in 18 simulated situations with 39 bachelor degree nursing students. In the situations, the scenarios, the actors and the plots were described. The story told was "the way from suffering to health" in which three main plots emerged. The first was, doing as performing and knowing, which took the shape of knowing what to do, acting responsibly, using evidence and equipment, appearing confident and feeling comfortable, and sharing work and information with others. The second was, being as encountering the patient, which took the shape of being there for him/her and confirming by listening and answering. The third plot was becoming as maturing and developing which took the shape of learning in co-operation with other students. All the deductive categories, shapes and expressions appeared as dialectic patterns having their negative counterparts. The study showed that clinical competence can be made evident and developed by simulation and that the challenge is in encountering the patient and his/her suffering. PMID:26763209

  13. Success and Failure in Helping SMEs. A Three-Year Observational Study.

    ERIC Educational Resources Information Center

    Stewardson, Dave; Coleman, Shirley

    2003-01-01

    A 3-year observational study of a project to help small and medium-sized enterprises (SMEs) conducted by a British university highlighted initial contacts and working methods that were effective. Results identified why some SMEs do not make full use of facilities offered and reasons for overall success. (Contains 13 references.) (JOW)

  14. 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

  15. 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.

  16. 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.

  17. 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.

  18. Staff reactions to challenging behaviour: an observation study.

    PubMed

    Lambrechts, Greet; Van Den Noortgate, Wim; Eeman, Lieve; Maes, Bea

    2010-01-01

    Staff reactions play an important role in the development and maintaining of clients' challenging behaviour. Because there is a paucity of research on staff reactions in naturalistic settings, this study examined sequential associations between challenging behaviour and staff reactions by means of a descriptive analysis. We analysed video recordings of the reactions of 10 staff members towards challenging behaviour of clients with severe or profound intellectual disabilities who displayed self-injurious behaviour, stereotyped behaviour and/or aggressive/destructive behaviour. As expected, the staff members used much verbal behaviours after challenging behaviour and often immediately tried to stop the challenging behaviour. Furthermore, staff often gave attention to challenging behaviour whereas offering or taking away material or tasks were less frequently observed reactions. Reactions to aggressive/destructive behaviour and self-injurious behaviour were quite similar. After stereotyped behaviour, not that many reactions occurred significantly more. Although this study has clinical implications and made a valuable contribution to research on staff reactions to challenging behaviour, more research is needed, more specifically, about the effectiveness of these staff reactions.

  19. Clipless laparoscopic cholecystectomy--a prospective observational study.

    PubMed

    Shah, J N; Maharjan, S B

    2010-06-01

    In laparoscopic cholecystectomy (LC), cystic duct and artery are normally secured with titanium clips. Intracorporeal ligation is normally superior to extra corporeal knotting. Most studies report of separate and multiple ligations of cystic duct and artery, which are viewed as technically demanding and time consuming. Similarly the harmonic scalpel and 'LigaSure' are prohibitory expensive for resource limited country like Nepal. After several modifications, we observed the success of intracorporeal "single ligation of cystic artery and duct" with free silk tie. From Jul to Oct 2009, after a pilot study and several modifications ofintracorporeal ligation, we successfully used single ligation of cystic artery and duct (SLAD) with free silk 2/0 in symptomatic cholelithiasis patients.80 cases undergoing elective laparoscopic cholecystectomy. There were 80 patients, females 71.0% (n=57). Average age of patients was 39 yr (14-65). We had no bile leak or other complications related to ligature. The time taken for tie varied from 2 to 7 minutes (average 3 min). In 3 cases, a 5th port was made to grasp and ligate the bleeding vessels. There were 19 (25.0%) acute calculus cholecystitis, including mucocele, empyema, gangrenous cholecystitis. Two patients (2.0%) had inflammation of umbilical port which healed spontaneously. This technique of intracorporeal single ligation of cystic artery and duct (SLAD) in LC is simple, safe and economical. SLAD do not increase operative time as only single tie is used. This no clip laparoscopic cholecystectomy (NCLC) eliminates the clip related complications.

  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. Unsafe driving behaviour and four wheel drive vehicles: observational study

    PubMed Central

    Walker, Lesley; Williams, Jonathan; Jamrozik, Konrad

    2006-01-01

    Objective To assess the level of compliance with the new law in the United Kingdom mandating penalties for using a hand held mobile phone while driving, to compare compliance with this law with the one on the use of seat belts, and to compare compliance with these laws between drivers of four wheel drive vehicles and drivers of normal cars. Design Observational study with two phases—one within the “grace” period, the other starting one week after penalties were imposed on drivers using such telephones. Setting Three busy sites in London. Participants Drivers of 38 182 normal cars and 2944 four wheel drive vehicles. Main outcome measures Proportions of drivers seen to be using hand held mobile phones and not using seat belts. Results Drivers of four wheel drive vehicles were more likely than drivers of other cars to be seen using hand held mobile phones (8.2% v 2.0%) and not complying with the law on seat belts (19.5% v 15.0%). Levels of non-compliance with both laws were slightly higher in the penalty phase of observation, and breaking one law was associated with increased likelihood of breaking the other. Conclusions The level of non-compliance with the law on the use of hand held mobile phones by drivers in London is high, as is non-compliance with the law on seat belts. Drivers of four wheel drive vehicles were four times more likely than drivers of other cars to be seen using hand held mobile phones and slightly more likely not to comply with the law on seat belts. PMID:16798755

  2. 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.

  3. 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

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

    PubMed

    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

  5. Quality of Life after Stapled Hemorrhoidopexy: A Prospective Observational Study

    PubMed Central

    Garg, Pankaj Kumar; Kumar, Gopal; Jain, Bhupendra Kumar; Mohanty, Debajyoti

    2013-01-01

    Objective. The objective of the study was to assess the change in quality of life (QOL) of patients undergoing stapled hemorrhoidopexy (SH) using WHO Quality of Life-BREF (WHOQOL-BREF) questionnaire. Methods. The study sample comprised patients with symptomatic II, III, and IV degree hemorrhoids, undergoing SH. The patients were asked to complete WHOQOL-BREF questionnaire before and one month following the surgery. Result. There were 20 patients in the study group. The postoperative pain score measured by visual analogue scale at six hours postoperatively was 7.60 ± 1.23, which reduced to 0.70 ± 0.92 at 24 hours. The items in the WHOQOL-BREF had high-internal consistency or reliability as shown by high Cronbach's alpha coefficient which was 0.82 and 0.90 for pre- and postoperative questionnaires. There was significant improvement in the overall perception of QOL and health, and in physical and psychological domains. There was modest improvement in environmental domain, while no change was noted in social domain. Conclusion. SH improved the quality of life of patients treated for hemorrhoids. PMID:24058916

  6. 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.

  7. Improving Resolution and Depth of Astronomical Observations via Modern Mathematical Methods for Image Analysis

    NASA Astrophysics Data System (ADS)

    Castellano, M.; Ottaviani, D.; Fontana, A.; Merlin, E.; Pilo, S.; Falcone, M.

    2015-09-01

    In the past years modern mathematical methods for image analysis have led to a revolution in many fields, from computer vision to scientific imaging. However, some recently developed image processing techniques successfully exploited by other sectors have been rarely, if ever, experimented on astronomical observations. We present here tests of two classes of variational image enhancement techniques: "structure-texture decomposition" and "super-resolution" showing that they are effective in improving the quality of observations. Structure-texture decomposition allows to recover faint sources previously hidden by the background noise, effectively increasing the depth of available observations. Super-resolution yields an higher-resolution and a better sampled image out of a set of low resolution frames, thus mitigating problematics in data analysis arising from the difference in resolution/sampling between different instruments, as in the case of EUCLID VIS and NIR imagers.

  8. Personality, Study Methods and Academic Performance

    ERIC Educational Resources Information Center

    Entwistle, N. J.; Wilson, J. D.

    1970-01-01

    A questionnaire measuring four student personality types--stable introvert, unstable introvert, stable extrovert and unstable extrovert--along with the Eysenck Personality Inventory (Form A) were give to 72 graduate students at Aberdeen University and the results showed recognizable interaction between study methods, motivation and personality…

  9. 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

  10. Dialyzing women and men: does it matter? An observational study

    PubMed Central

    Artan, Ayse Serra; Kircelli, Fatih; Ok, Ercan; Yilmaz, Murvet; Asci, Gulay; Dogan, Cengiz; Oto, Ozgur; Gunestepe, Kutay; Basci, Ali; Sever, Mehmet Sukru

    2016-01-01

    Background Application and consequences of hemodialysis treatment may differ between genders; focusing on these differences may be useful to optimize outcomes. Methods Data from 1 999 648 hemodialysis sessions performed in 10 984 (3316 incident and 7668 prevalent) patients, treated in 55 centers of the European Clinical Database (EuCliD)–Turkey, were analyzed, and various demographic, clinical, biochemical, therapeutic and prognostic parameters were compared. Results There were 1905 male and 1411 female incident and 4339 male and 3329 female prevalent patients. For females, the mean age in incident (61.8 ± 14.9 years) and prevalent (58.3 ± 15.2 years) patients was higher than for males (60.2 ± 14.8 and 56.5 ± 14.9 years, respectively) (P < 0.001 for both analyses). Also, body mass index was higher, while the hemoglobin level, and the percentage of interdialytic weight gain and arteriovenous fistula were lower. Serum phosphorus was similar in both genders in incident cases, while it was lower in prevalent female patients. Serum parathyroid hormone levels were lower in incident, but higher in prevalent male cases. Erythropoiesis-stimulating agents and vitamin D preparations were more frequently used in female incident and prevalent patients. Hospitalization was more frequent in prevalent females, while it did not differ significantly in the incident cases. Overall, no significant difference was observed in survival rates at 3 years in both incident and prevalent male and female patients. Conclusions Many parameters differ significantly between female and male dialysis patients. Considering the effects of sex on several parameters may be a valuable approach for achieving better outcomes when formulating treatment strategies in this patient population. PMID:27274838

  11. 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.

  12. A method for real-time in vitro observation of cavitation on prosthetic heart valves.

    PubMed

    Zapanta, C M; Liszka, E G; Lamson, T C; Stinebring, D R; Deutsch, S; Geselowitz, D B; Tarbell, J M

    1994-11-01

    A method for real-time in vitro observation of cavitation on a prosthetic heart valve has been developed. Cavitation of four blood analog fluids (distilled water, aqueous glycerin, aqueous polyacrylamide, and aqueous xanthan gum) has been documented for a Medtronic/Hall prosthetic heart valve. This method employed a Penn State Electrical Ventricular Assist Device in a mock circulatory loop that was operated in a partial filling mode associated with reduced atrial filling pressure. The observations were made on a valve that was located in the mitral position, with the cavitation occurring on the inlet side after valve closure on every cycle. Stroboscopic videography was used to document the cavity life cycle. Bubble cavitation was observed on the valve occluder face. Vortex cavitation was observed at two locations in the vicinity of the valve occluder and housing. For each fluid, cavity growth and collapse occurred in less than one millisecond, which provides strong evidence that the cavitation is vaporous rather than gaseous. The cavity duration time was found to decrease with increasing atrial pressure at constant aortic pressure and beat rate. The area of cavitation was found to decrease with increasing delay time at a constant aortic pressure, atrial pressure, and beat rate. Cavitation was found to occur in each of the fluids, with the most cavitation seen in the Newtonian fluids (distilled water and aqueous glycerin). PMID:7869722

  13. 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.

  14. Formal Methods Case Studies for DO-333

    NASA Technical Reports Server (NTRS)

    Cofer, Darren; Miller, Steven P.

    2014-01-01

    RTCA DO-333, Formal Methods Supplement to DO-178C and DO-278A provides guidance for software developers wishing to use formal methods in the certification of airborne systems and air traffic management systems. The supplement identifies the modifications and additions to DO-178C and DO-278A objectives, activities, and software life cycle data that should be addressed when formal methods are used as part of the software development process. This report presents three case studies describing the use of different classes of formal methods to satisfy certification objectives for a common avionics example - a dual-channel Flight Guidance System. The three case studies illustrate the use of theorem proving, model checking, and abstract interpretation. The material presented is not intended to represent a complete certification effort. Rather, the purpose is to illustrate how formal methods can be used in a realistic avionics software development project, with a focus on the evidence produced that could be used to satisfy the verification objectives found in Section 6 of DO-178C.

  15. A European Network for Atmospheric Hydrogen observations and studies: EUROHYDROS

    NASA Astrophysics Data System (ADS)

    Werner, A.; Engel, A.

    2008-12-01

    and the EuroHydros team In a future energy supply chain, molecular hydrogen is expected to play an increasingly important role as a carrier of energy for mobile applications, in particular in the automotive sector. Such an increased use of molecular hydrogen is prone to lead to additional emissions into the atmosphere, due to leakages in the supply chain. While molecular hydrogen does not influence the radiation budget of the atmosphere directly, it affects its oxidation capacity, through reaction with the OH radical. This in turn leads to an increased atmospheric lifetime of many atmospheric constituents (e.g. Methane), making H2 an indirect greenhouse gas. An increase of molecular hydrogen in the atmosphere also leads to increasing H2O in the stratosphere, influencing the radiation budget of the atmosphere and ozone chemistry. In the light of these uncertainties, a thorough understanding of hydrogen in the atmosphere is necessary, and, most notably, a good understanding of the present day global distribution and budget of atmospheric hydrogen. The EU funded project Eurohydros aims at improving the understanding of the budget of molecular hydrogen in the atmosphere through a combination of atmospheric monitoring, source-sink studies and modelling work. In this presentation we focus on the observational network, showing first results from different European and Global sites, from the calibration of the data sets and a first intercomparison experiment.

  16. 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

  17. 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

  18. Safety of Tdap vaccine in pregnant women: an observational study

    PubMed Central

    Petousis-Harris, Helen; Walls, Tony; Watson, Donna; Paynter, Janine; Graham, Patricia; Turner, Nikki

    2016-01-01

    Objectives Actively recruit and intensively follow pregnant women receiving a dose of acellular pertussis vaccine for 4 weeks after vaccination. Design and settings A prospective observational study conducted in 2 New Zealand regions. Participants Women in their 28th–38th week of pregnancy, recruited from primary care and antenatal clinics at the time of Tdap administration. Telephone interviews were conducted at 48 h and 4 weeks postvaccination. Main outcomes measures Outcomes were injection site reactions, systemic symptoms and serious adverse events (SAEs). Where available, data have been classified and reported according to Brighton Collaboration definitions. Results 793 women participated with 27.9% receiving trivalent inactivated influenza vaccine concomitantly. 79% of participants reported mild or moderate pain and 2.6% severe pain. Any swelling was reported by 7.6%, induration by 12.0% (collected from 1 site only, n=326), and erythema by 5.8% of participants. Fever was reported by 17 (2.1%) participants, 14 of these occurred within 24 h. Headache, dizziness, nausea, myalgia or arthralgia was reported by <4% of participants, respectively, and fatigue by 8.4%. During the study period, there were 115 adverse events in 113 participants, most of which were minor. At the end of the reporting period, 31 events were classified as serious (eg, obstetric bleeding, hypertension, infection, tachycardia, preterm labour, exacerbation of pre-existing condition and pre-eclampsia). All had variable onset time from vaccination. There were two perinatal deaths. Clinician assessment of all SAEs found none likely to be vaccine related. Conclusions Vaccination with Tdap in pregnant women was well tolerated with no SAE likely to be caused by the vaccine. Trial registration number ACTRN12613001045707. PMID:27091823

  19. 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.

  20. Application of an inverse method to interpret 231Pa/230Th observations from marine sediments

    NASA Astrophysics Data System (ADS)

    Burke, Andrea; Marchal, Olivier; Bradtmiller, Louisa I.; McManus, Jerry F.; François, Roger

    2011-03-01

    Records of 231Pa/230Th from Atlantic sediments have been interpreted to reflect changes in ocean circulation during the geologic past. Such interpretations should be tested with due regard to the limited spatial coverage of 231Pa/230Th data and the uncertainties in our current understanding of the behavior of both nuclides in the ocean. Here an inverse method is used to evaluate the information contained in 231Pa/230Th compilations for the Holocene, Last Glacial Maximum (LGM), and Heinrich Event 1 (H1). An estimate of the abyssal circulation in the modern Atlantic Ocean is obtained by combining hydrographic observations and dynamical constraints. Then sediment 231Pa/230Th data for each time interval are combined with an advection-scavenging model in order to determine their (in)consistency with the modern circulation estimate. We find that the majority of sediment 231Pa/230Th data for the Holocene, LGM, or H1 can be brought into consistency with the modern circulation if plausible assumptions are made about the large-scale distribution of 231Pa and about model uncertainties. Moreover, the adjustments in the data needed to reach compatibility with a hypothetical state of no flow (no advection) are positively biased for each time interval, suggesting that the 231Pa/230Th data (including that for H1) are more consistent with a persistence of some circulation than with no circulation. Our study does not imply that earlier claims of a circulation change during the LGM or H1 are inaccurate, but that these claims cannot be given a rigorous basis given the current uncertainties involved in the analysis of the 231Pa/230Th data.

  1. Research on a UAV path planning method for ground observation based on threat sources

    NASA Astrophysics Data System (ADS)

    Yan, Hao; Fan, Xing; Xia, Xuezhi; Lin, Linshu

    2008-12-01

    The path planning method is one of the main research directions in current UAV(unmanned aerial vehicle) technologies. In this paper we perform analyses on the adversarial environment which may be broken through during the UAV mission for ground observation, and carry out the grade classification according to the threat level. On the basis of genetic algorithm, the encoding method of dimension reduction and direct quantization is used to combine the threat value of each leg with the flight distance, so as to construct the fitness evaluation function based on the threat amount and design the algorithm. This method is proven to be able to converge effectively and quickly via the simulation experiments, which meet the threat restriction and applicability of UAV in route planning.

  2. 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.

  3. Trigeminocardiac reflex in neurosurgical practice: An observational prospective study

    PubMed Central

    Etezadi, Farhad; Orandi, Amir Ali; Orandi, Amir Hosein; Najafi, Atabak; Amirjamshidi, Abbas; Pourfakhr, Pejman; Khajavi, Mohammad Reza; Abbassioun, Kazem

    2013-01-01

    Background: Considering wide variations regarding the incidence of trigeminocardiac reflex (TCR) during cranial neurosurgical procedures, and paucity of reliable data, we intended to design a prospective study to determine the incidence of TCR in patients undergoing standard general anesthesia for surgery of supra/infra-tentorial cranial and skull base lesions. Methods: A total of 190 consecutive patients candidate for elective surgery of supra-tentorial, infra-tentorial, and skull base lesions were enrolled. All the patients were operated in the neurosurgical operating room of a university-affiliated teaching hospital. All surgeries were performed using sufficient depth of anesthesia achieved by titration of propofol–alfentanil mixture, adjusted according to target Cerebral State Index (CSI) values (40-60). All episodes of bradycardia and hypotension indicating the occurrence of TCR during the surgery (sudden decrease of more than 20% from the previous level) were recorded. Results: Four patients, two female and two male, developed episodes of TCR during surgery (4/190; 2.1%). Three patients showed one episode of TCR just at the end of operation when the skin sutures were applied while CSI values were 70-77 and in the last case, when small tumor samples were taken from just beneath the lateral wall of the cavernous sinus TCR episode was seen while the CSI value was 51. Conclusion: TCR is a rare phenomenon during brain surgeries when patient is anesthetized using standard techniques. Keeping the adequate depth of anesthesia using CSI monitoring method may be an advisable strategy during whole period of a neurosurgical procedure. PMID:24083052

  4. Primary care capitation payments in the UK. An observational study

    PubMed Central

    2010-01-01

    Background In 2004 an allocation formula for primary care services was introduced in England and Wales so practices would receive equitable pay. Modifications were made to this formula to enable local health authorities to pay practices. Similar pay formulae were introduced in Scotland and Northern Ireland, but these are unique to the country and therefore could not be included in this study. Objective To examine the extent to which the Global Sum, and modifications to the original formula, determine practice funding. Methods The allocation formula determines basic practice income, the Global Sum. We compared practice Global Sum entitlements using the original and the modified allocation formula calculations. Practices receive an income supplement if Global Sum payments were below historic income in 2004. We examined current overall funding levels to estimate what the effect will be when the income supplements are removed. Results Virtually every Welsh and English practice (97%) received income supplements in 2004. Without the modifications to the formula only 72% of Welsh practices would have needed supplements. No appreciable change would have occurred in England. The formula modifications increased the Global Sum for 99.5% of English practices, while it reduced entitlement for every Welsh practice. In 2008 Welsh practices received approximately £6.15 (9%) less funding per patient per year than an identical English practice. This deficit will increase to 11.2% when the Minimum Practice Income Guarantee is abolished. Conclusions Identical practices in different UK countries do not receive equitable pay. The pay method disadvantages Wales where the population is older and has higher health needs. PMID:20529330

  5. Developing Best Practices Teaching Procedures for Skinfold Assessment: Observational Examination Using the Think Aloud Method

    ERIC Educational Resources Information Center

    Holmstrup, Michael E.; Verba, Steven D.; Lynn, Jeffrey S.

    2015-01-01

    Skinfold assessment is valid and economical; however, it has a steep learning curve, and many programs only include one exposure to the technique. Increasing the number of exposures to skinfold assessment within an undergraduate curriculum would likely increase skill proficiency. The present study combined observational and Think Aloud…

  6. 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

  7. 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

  8. A systematic review of observational studies evaluating costs of adverse drug reactions

    PubMed Central

    Batel Marques, Francisco; Penedones, Ana; Mendes, Diogo; Alves, Carlos

    2016-01-01

    Introduction The growing evidence of the increased frequency and severity of adverse drug events (ADEs), besides the negative impact on patient’s health status, indicates that costs due to ADEs may be steadily rising. Observational studies are an important tool in pharmacovigilance. Despite these studies being more susceptible to bias than experimental designs, they are more competent in assessing ADEs and their associated costs. Objective To identify and characterize the best available evidence on ADE-associated costs. Methods MEDLINE, Cochrane Library, and Embase were searched from 1995 to 2015. Observational studies were included. The methodological quality of selected studies was assessed by Cochrane Collaboration tool for experimental and observational studies. Studies were classified according to the setting analyzed in “ambulatory”, “hospital”, or both. Costs were classified as “direct” and “indirect”. Data were analyzed using descriptive statistics. The total incremental cost per patient with ADE was estimated. Results Twenty-nine (94%) longitudinal observational studies and two (7%) cross-sectional studies were included. Twenty-three (74%) studies were assessed with the highest methodological quality score. The studies were mainly conducted in the US (61%). Twenty (65%) studies evaluated any therapeutic group. Twenty (65%) studies estimated costs of ADEs leading to or prolonging hospitalization. The “direct costs” were evaluated in all studies, whereas only two (7%) also estimated the “indirect costs”. The “direct costs” in ambulatory ranged from €702.21 to €40,273.08, and the in hospital from €943.40 to €7,192.36. Discussion Methodological heterogeneities were identified among the included studies, such as design, type of ADEs, suspected drugs, and type and structure of costs. Despite such discrepancies, the financial burden associated with ADE costs was found to be high. In the light of the present findings

  9. A systematic review of observational studies evaluating costs of adverse drug reactions

    PubMed Central

    Batel Marques, Francisco; Penedones, Ana; Mendes, Diogo; Alves, Carlos

    2016-01-01

    Introduction The growing evidence of the increased frequency and severity of adverse drug events (ADEs), besides the negative impact on patient’s health status, indicates that costs due to ADEs may be steadily rising. Observational studies are an important tool in pharmacovigilance. Despite these studies being more susceptible to bias than experimental designs, they are more competent in assessing ADEs and their associated costs. Objective To identify and characterize the best available evidence on ADE-associated costs. Methods MEDLINE, Cochrane Library, and Embase were searched from 1995 to 2015. Observational studies were included. The methodological quality of selected studies was assessed by Cochrane Collaboration tool for experimental and observational studies. Studies were classified according to the setting analyzed in “ambulatory”, “hospital”, or both. Costs were classified as “direct” and “indirect”. Data were analyzed using descriptive statistics. The total incremental cost per patient with ADE was estimated. Results Twenty-nine (94%) longitudinal observational studies and two (7%) cross-sectional studies were included. Twenty-three (74%) studies were assessed with the highest methodological quality score. The studies were mainly conducted in the US (61%). Twenty (65%) studies evaluated any therapeutic group. Twenty (65%) studies estimated costs of ADEs leading to or prolonging hospitalization. The “direct costs” were evaluated in all studies, whereas only two (7%) also estimated the “indirect costs”. The “direct costs” in ambulatory ranged from €702.21 to €40,273.08, and the in hospital from €943.40 to €7,192.36. Discussion Methodological heterogeneities were identified among the included studies, such as design, type of ADEs, suspected drugs, and type and structure of costs. Despite such discrepancies, the financial burden associated with ADE costs was found to be high. In the light of the present findings

  10. Study of the Socratic method during cognitive restructuring.

    PubMed

    Froján-Parga, María Xesús; Calero-Elvira, Ana; Montaño-Fidalgo, Montserrat

    2011-01-01

    Cognitive restructuring, in particular in the form of the Socratic method, is widely used by clinicians. However, little research has been published with respect to underlying processes, which has hindered well-accepted explanations of its effectiveness. The aim of this study is to present a new method of analysis of the Socratic method during cognitive restructuring based on the observation of the therapist's verbal behaviour. Using recordings from clinical sessions, 18 sequences were selected in which the Socratic method was applied by six cognitive-behavioural therapists working at a private clinical centre in Madrid. The recordings involved eight patients requiring therapy for various psychological problems. Observations were coded using a category system designed by the authors and that classifies the therapist's verbal behaviour into seven hypothesized functions based on basic behavioural operations. We used the Observer XT software to code the observed sequences. The results are summarized through a preliminary model which considers three different phases of the Socratic method and some functions of the therapist's verbal behaviour in each of these phases: discriminative and reinforcement functions in the starting phase, informative and motivational functions in the course of the debate, and instructional and reinforcement functions in the final phase. We discuss the long-term potential clinical benefits of the current proposal. 

  11. Study of Seismic Activity Using Geophysical and Radio Physical Equipment for Observation

    NASA Astrophysics Data System (ADS)

    Kvavadze, N.; Tsereteli, N. S.

    2015-12-01

    One of the most dangerous and destructive natural hazards are earthquakes, which is confirmed by recent earthquakes such as Nepal 2015, Japan and Turkey 2011. Because of this, study of seismic activity is important. Studying any process, it is necessary to use different methods of observation, which allows us to increase accuracy of obtained data. Seismic activity is a complex problem and its study needs different types of observation methods. Two main problems of seismic activity study are: reliable instrumental observations and earthquake short-term predictions. In case of seismic risks it is necessary to have reliable accelerometer data. One of the most promising field in earthquake short-term prediction is very low frequency (VLF) electromagnetic wave propagation in ionosphere observation. To study Seismic activity of Caucasus region, was created observation complex using Accelerometer, Velocimeter and VLF electromagnetic waves received from communication stations (located in different area of the world) reflected from low ionosphere. System is created and operates at Tbilisi State University Ionosphere Observatory, near Tbilisi in Tabakhmela 42.41'70 N, 44.80'92 E, Georgia. Data obtained is sent to a local server located at M. Nodia Institute of Geophysics, TSU, for storage and processing. Diagram for complex is presented. Also data analysis methods were created and preliminary processing was done. In this paper we present some of the results: Earthquake data from ionosphere observations as well as local earthquakes recorded with accelerometer and velocimeter. Complex is first in 6 that will be placed around Georgia this year. We plan on widening network every year.

  12. 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.

  13. Method for repair of defects in range data observed with a laser range scanner

    NASA Astrophysics Data System (ADS)

    Saito, Takahiro; Komatsu, Takashi; Sunaga, Shin-ichi

    2003-05-01

    Some types of laser range scanner can measure both range data and color texture data simultaneously from the same viewpoint, and are often used to acquire 3D structure of outdoor scenery. However, for outdoor scenery, unfortunately a laser range scanner cannot give us perfect range information about the target objects such as buildings, and various factors incur critical defects of range data. We present a defect detection method based on region segmentation using observed range and color data, and employ a nonlinear PDE (Partial Differential Equation)-based method to repair detected defect regions of range data. As to the defect detection, performing range-and-color segmentation, we divide observed data into several regions that correspond to buildings, trees, the sky, the ground, persons, street furniture, etc. Using the segmentation results, we extract occlusion regions of buildings as defects regions. Once the defect regions are extracted, 3D position data or range data will be repaired from the observed data in their neighborhoods. For that purpose, we adapt the digital inpainting algorithm, originally developed for the color image repair problem, for this 3D range data repair problem. This algorithm is formulated as the nonlinear time-evolution procedure based on the geometrical nonlinear PDE.

  14. A method to improve the utilization of GNSS observation for water vapor tomography

    NASA Astrophysics Data System (ADS)

    Yao, Y. B.; Zhao, Q. Z.; Zhang, B.

    2016-01-01

    Existing water vapor tomographic methods use Global Navigation Satellite System (GNSS) signals penetrating the entire research area while they do not consider signals passing through its sides. This leads to the decreasing use of observed satellite signals and allows for no signals crossing from the bottom or edge areas especially for those voxels in research areas of interest. Consequently, the accuracy of the tomographic results for the bottom of a research area, and the overall reconstructed accuracy do not reach their full potential. To solve this issue, an approach which uses GPS data with both signals that pass the side and top of a research area is proposed. The advantages of proposed approach include improving the utilization of existing GNSS observations and increasing the number of voxels crossed by satellite signals. One point should be noted that the proposed approach needs the support of radiosonde data inside the tomographic region. A tomographic experiment was implemented using observed GPS data from the Continuously Operating Reference System (CORS) Network of Zhejiang Province, China. The comparison of tomographic results with data from a radiosonde shows that the root mean square error (RMS), bias, mean absolute error (MAE), and standard deviation (SD) of the proposed approach are superior to those of the traditional method.

  15. Identifying observational studies of surgical interventions in MEDLINE and EMBASE

    PubMed Central

    Fraser, Cynthia; Murray, Alison; Burr, Jennifer

    2006-01-01

    Background Health technology assessments of surgical interventions frequently require the inclusion of non-randomised evidence. Literature search strategies employed to identify this evidence often exclude a methodological component because of uncertainty surrounding the use of appropriate search terms. This can result in the retrieval of a large number of irrelevant records. Methodological filters would help to minimise this, making literature searching more efficient. Methods An objective approach was employed to develop MEDLINE and EMBASE filters, using a reference standard derived from screening the results of an electronic literature search that contained only subject-related terms. Candidate terms for MEDLINE (N = 37) and EMBASE (N = 35) were derived from examination of the records of the reference standard. The filters were validated on two sets of studies that had been included in previous health technology assessments. Results The final filters were highly sensitive (MEDLINE 99.5%, EMBASE 100%, MEDLINE/EMBASE combined 100%) with precision ranging between 16.7% – 21.1%, specificity 35.3% – 43.5%, and a reduction in retrievals of over 30%. Against the validation standards, the individual filters retrieved 85.2% – 100% of records. In combination, however, the MEDLINE and EMBASE filters retrieved 100% against both validation standards with a reduction in retrieved records of 28.4% and 30.1% Conclusion The MEDLINE and EMBASE filters were highly sensitive and substantially reduced the number of records retrieved, indicating that they are useful tools for efficient literature searching. PMID:16919159

  16. Transgenerational tobacco smoke exposure and childhood cancer: An observational study

    PubMed Central

    Ortega-García, Juan A; Martin, Marlene; López-Fernández, María T; Fuster-Soler, Jose L; Donat-Colomer, Joaquín; López-Ibor, Blanca; Claudio, Luz; Ferrís-Tortajada, Josep

    2011-01-01

    Aim Although tobacco smoke is an established risk factor for adult cancer, studies of the association between parental smoking and childhood cancer have produced inconsistent results. To investigate the transgenerational relationship between pre-natal and post-natal tobacco smoke exposure from the grandmother’s pregnancies until after the post-natal period and childhood cancer. Methods Exposure to tobacco smoke was recorded for three generations. Data were collected through personal interviews using the paediatric environmental history, and were compared among 128 children with cancer and 128 matched controls. The contingency tables and a logistic multivariable regression model were used to control for possible confounding factors. Results Smoke exposure during oogenesis (maternal grandmother smokers) – odds ratio (OR) 2.2 (95% confidence interval (CI) 1.1–4.9) – and during the mother’ pregnancies – OR 1.8 (95% CI 1.1–3.3) – were significantly associated with an increased risk of childhood cancer. Conclusions Tobacco smoke exposure during the grandmother’s and mother’s pregnancies increase the risk of cancer in the descendants. The results suggest that the biological plausibility of the association between parental smoking and paediatric cancer can be explained by the large latency period of paediatric carcinogenesis. PMID:20412413

  17. Reducing impacts of systematic errors in the observation data on inversing ecosystem model parameters using different normalization methods

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Xu, M.; Huang, M.; Yu, G.

    2009-11-01

    Modeling ecosystem carbon cycle on the regional and global scales is crucial to the prediction of future global atmospheric CO2 concentration and thus global temperature which features large uncertainties due mainly to the limitations in our knowledge and in the climate and ecosystem models. There is a growing body of research on parameter estimation against available carbon measurements to reduce model prediction uncertainty at regional and global scales. However, the systematic errors with the observation data have rarely been investigated in the optimization procedures in previous studies. In this study, we examined the feasibility of reducing the impact of systematic errors on parameter estimation using normalization methods, and evaluated the effectiveness of three normalization methods (i.e. maximum normalization, min-max normalization, and z-score normalization) on inversing key parameters, for example the maximum carboxylation rate (Vcmax,25) at a reference temperature of 25°C, in a process-based ecosystem model for deciduous needle-leaf forests in northern China constrained by the leaf area index (LAI) data. The LAI data used for parameter estimation were composed of the model output LAI (truth) and various designated systematic errors and random errors. We found that the estimation of Vcmax,25 could be severely biased with the composite LAI if no normalization was taken. Compared with the maximum normalization and the min-max normalization methods, the z-score normalization method was the most robust in reducing the impact of systematic errors on parameter estimation. The most probable values of estimated Vcmax,25 inversed by the z-score normalized LAI data were consistent with the true parameter values as in the model inputs though the estimation uncertainty increased with the magnitudes of random errors in the observations. We concluded that the z-score normalization method should be applied to the observed or measured data to improve model parameter

  18. A novel method for observing proteins in vivo using a small fluorescent label and multiphoton imaging.

    PubMed

    Botchway, Stanley W; Barba, Ignasi; Jordan, Randolf; Harmston, Rebecca; Haggie, Peter M; Williams, Simon-Peter; Fulton, Alexandra M; Parker, Anthony W; Brindle, Kevin M

    2005-09-15

    A novel method for the fluorescence detection of proteins in cells is described in the present study. Proteins are labelled by the selective biosynthetic incorporation of 5-hydroxytryptophan and the label is detected via selective two-photon excitation of the hydroxyindole and detection of its fluorescence emission at 340 nm. The method is demonstrated in this paper with images of a labelled protein in yeast cells.

  19. Funding sources for continuing medical education: An observational study

    PubMed Central

    Venkataraman, Ramesh; Ranganathan, Lakshmi; Ponnish, Arun S.; Abraham, Babu K.; Ramakrishnan, Nagarajan

    2014-01-01

    Aims: Medical accreditation bodies and licensing authorities are increasingly mandating continuing medical education (CME) credits for maintenance of licensure of healthcare providers. However, the costs involved in participating in these CME activities are often substantial and may be a major deterrent in obtaining these mandatory credits. It is assumed that healthcare providers often obtain sponsorship from their institutions or third party payers (i.e. pharmaceutical-industry) to attend these educational activities. Data currently does not exist exploring the funding sources for CME activities in India. In this study, we examine the relative proportion of CME activities sponsored by self, institution and the pharmaceutical-industry. We also wanted to explore the characteristics of courses that have a high proportion of self-sponsorship. Materials and Methods: This is a retrospective audit of the data during the year 2009 conducted at an autonomous clinical training academy. The details of the sponsor of each CME activity were collected from an existing database. Participants were subsequently categorized as sponsored by self, sponsored by institution or sponsored by pharmaceutical-industry. Results: In the year 2009, a total of 2235 participants attended 40 different CME activities at the training academy. Of the total participants, 881 (39.4%) were sponsored by self, 898 (40.2%) were sponsored by institution and 456 (20.3%) by pharmaceutical-industry. About 47.8% participants attended courses that carried an international accreditation. For the courses that offer international accreditation, 63.3% were sponsored by self, 34.9% were sponsored by institution and 1.6% were sponsored by pharmaceutical-industry. There were 126 participants (5.6%) who returned to the academy for another CME activity during the study period. Self-sponsored (SS) candidates were more likely to sponsor themselves again for subsequent CME activity compared with the other two groups (P < 0

  20. Slip distribution of the 2010 Mentawai earthquake from GPS observation using least squares inversion method

    NASA Astrophysics Data System (ADS)

    Awaluddin, Moehammad; Yuwono, Bambang Darmo; Puspita, Yolanda Adya

    2016-05-01

    Continuous Global Positioning System (GPS) observations showed significant crustal displacements as a result of the 2010 Mentawai earthquake. The Least Square Inversion method of Mentawai earthquake slip distribution from SuGAR observations yielded in an optimum value of slip distribution by giving a weight of smoothing constraint and a weight of slip value constraint = 0 at the edge of the earthquake rupture area. A maximum coseismic slip of the inversion calculation was 1.997 m and concentrated around stations PRKB (Pagai Island). In addition, the values of dip-slip direction tend to be more dominant. The seismic moment calculated from the slip distribution was 6.89 × 10E+20 Nm, which is equivalent to a magnitude of 7.8.

  1. Observational Epidemiologic Studies of Nutrition and Cancer: The Next Generation (with Better Observation)

    PubMed Central

    Schatzkin, Arthur; Subar, Amy F.; Moore, Steven; Park, Yikyung; Potischman, Nancy; Thompson, Frances E.; Leitzmann, Michael; Hollenbeck, Albert; Morrissey, Kerry Grace; Kipnis, Victor

    2009-01-01

    It would be of enormous public health importance if diet and physical activity—both modifiable behavioral factors--were causally related to cancer. Nevertheless, the nutritional epidemiology of cancer remains problematic, in part because of persistent concerns that standard questionnaires measure diet and physical activity with too much error. We present a new strategy for addressing this measurement error problem. First, as background, we note that food frequency and physical activity questionnaires require respondents to report ‘typical’ diet or activity over the previous year or longer. Multiple 24-hour recalls (24HR), based on reporting only the previous day’s behavior, offer potential cognitive advantages over the questionnaires, and biomarker evidence suggests the 24HR is more accurate than the food frequency questionnaire. The expense involved in administering multiple 24HRs in large epidemiologic studies, however, has up to now been prohibitive. In that context, we suggest that internet-based 24HRs, for both diet and physical activity, represent a practical and cost-effective approach for incorporating multiple recalls in large epidemiologic studies. We discuss 1) recent efforts to develop such internet-based instruments and their accompanying software support systems; 2) ongoing studies to evaluate the feasibility of using these new instruments in cohort studies; 3) additional investigations to gauge the accuracy of the internet-based recalls vis-à-vis standard instruments and biomarkers; and 4) new statistical approaches for combining the new instruments with standard assessment tools and biomarkers The incorporation of internet-based 24HRs into large epidemiologic studies may help advance our understanding of the nutritional determinants of cancer. PMID:19336550

  2. ICESat Observations of Inland Surface Water Stage, Slope, and Extent: a New Method for Hydrologic Monitoring

    NASA Technical Reports Server (NTRS)

    Harding, David J.; Jasinski, Michael F.

    2004-01-01

    River discharge and changes in lake, reservoir and wetland water storage are critical terms in the global surface water balance, yet they are poorly observed globally and the prospects for adequate observations from in-situ networks are poor (Alsdorf et al., 2003). The NASA-sponsored Surface Water Working Group has established a framework for advancing satellite observations of river discharge and water storage changes which focuses on obtaining measurements of water surface height (stage), slope, and extent. Satellite laser altimetry, which can achieve centimeter-level elevation precision for single, small laser footprints, provides a method to obtain these inland water parameters and contribute to global water balance monitoring. Since its launch in January, 2003 the Ice, Cloud, and land Elevation Satellite (ICESat), a NASA Earth Observing System mission, has achieved over 540 million laser pulse observations of ice sheet, ocean surface, land topography, and inland water elevations and cloud and aerosol height distributions. By recording the laser backscatter from 80 m diameter footprints spaced 175 m along track, ICESat acquires globally-distributed elevation profiles, using a 1064 nm laser altimeter channel, and cloud and aerosol profiles, using a 532 nm atmospheric lidar channel. The ICESat mission has demonstrated the following laser altimeter capabilities relevant to observations of inland water: (1) elevation measurements with a precision of 2 to 3 cm for flat surfaces, suitable for detecting river surface slopes along long river reaches or between multiple crossings of a meandering river channel, (2) from the laser backscatter waveform, detection of water surface elevations beneath vegetation canopies, suitable for measuring water stage in flooded forests, (3) single pulse absolute elevation accuracy of about 50 cm (1 sigma) for 1 degree sloped surfaces, with calibration work in progress indicating that a final accuracy of about 12 cm (1 sigma) will be

  3. A method to search for solar flares jointly observed by multiple instruments.

    NASA Astrophysics Data System (ADS)

    Milligan, Ryan

    2016-07-01

    Our current fleet of space-based solar observatories offer us a wealth of opportunities to study solar flares over a range of wavelengths, and the greatest advances in our understanding of flare physics often come from coordinated observations between different instruments. However, despite considerable effort to try and coordinate this armada of instruments over the years (e.g. through the Max Millennium Program of Solar Flare Research), there are frustratingly few solar flares that have been well and truly observed by most or all instruments simultaneously. This is due to a range of factors such as instruments having a limited field of view, satellites in low-Earth orbit going into eclipse, and observing schedules being uploaded days in advance. I shall describe a new technique to retrospectively search archival databases for flares jointly observed by RHESSI, SDO/EVE, Hinode/EIS+SOT, and IRIS. I shall also present a summary of how many flares have been observed by different configurations of these instruments since the launch of SDO.

  4. Method for Fusing Observational Data and Chemical Transport Model Simulations To Estimate Spatiotemporally Resolved Ambient Air Pollution.

    PubMed

    Friberg, Mariel D; Zhai, Xinxin; Holmes, Heather A; Chang, Howard H; Strickland, Matthew J; Sarnat, Stefanie Ebelt; Tolbert, Paige E; Russell, Armistead G; Mulholland, James A

    2016-04-01

    Investigations of ambient air pollution health effects rely on complete and accurate spatiotemporal air pollutant estimates. Three methods are developed for fusing ambient monitor measurements and 12 km resolution chemical transport model (CMAQ) simulations to estimate daily air pollutant concentrations across Georgia. Temporal variance is determined by observations in one method, with the annual mean CMAQ field providing spatial structure. A second method involves scaling daily CMAQ simulated fields using mean observations to reduce bias. Finally, a weighted average of these results based on prediction of temporal variance provides optimized daily estimates for each 12 × 12 km grid. These methods were applied to daily metrics of 12 pollutants (CO, NO2, NOx, O3, SO2, PM10, PM2.5, and five PM2.5 components) over the state of Georgia for a seven-year period (2002-2008). Cross-validation demonstrates a wide range in optimized model performance across pollutants, with SO2 predicted most poorly due to limitations in coal combustion plume monitoring and modeling. For the other pollutants studied, 54-88% of the spatiotemporal variance (Pearson R(2) from cross-validation) was captured, with ozone and PM2.5 predicted best. The optimized fusion approach developed provides daily spatial field estimates of air pollutant concentrations and uncertainties that are consistent with observations, emissions, and meteorology. PMID:26923334

  5. 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.

  6. Observational Studies of Parameters Influencing Air-sea Gas Exchange

    NASA Astrophysics Data System (ADS)

    Schimpf, U.; Frew, N. M.; Bock, E. J.; Hara, T.; Garbe, C. S.; Jaehne, B.

    A physically-based modeling of the air-sea gas transfer that can be used to predict the gas transfer rates with sufficient accuracy as a function of micrometeorological parameters is still lacking. State of the art are still simple gas transfer rate/wind speed relationships. Previous measurements from Coastal Ocean Experiment in the Atlantic revealed positive correlations between mean square slope, near surface turbulent dis- sipation, and wind stress. It also demonstrated a strong negative correlation between mean square slope and the fluorescence of surface-enriched colored dissolved organic matter. Using heat as a proxy tracer for gases the exchange process at the air/water interface and the micro turbulence at the water surface can be investigated. The anal- ysis of infrared image sequences allow the determination of the net heat flux at the ocean surface, the temperature gradient across the air/sea interface and thus the heat transfer velocity and gas transfer velocity respectively. Laboratory studies were carried out in the new Heidelberg wind-wave facility AELOTRON. Direct measurements of the Schmidt number exponent were done in conjunction with classical mass balance methods to estimate the transfer velocity. The laboratory results allowed to validate the basic assumptions of the so called controlled flux technique by applying differ- ent tracers for the gas exchange in a large Schmidt number regime. Thus a modeling of the Schmidt number exponent is able to fill the gap between laboratory and field measurements field. Both, the results from the laboratory and the field measurements should be able to give a further understanding of the mechanisms controlling the trans- port processes across the aqueous boundary layer and to relate the forcing functions to parameters measured by remote sensing.

  7. Observing power blackouts from space - A disaster related study

    NASA Astrophysics Data System (ADS)

    Aubrecht, C.; Elvidge, C. D.; Ziskin, D.; Baugh, K. E.; Tuttle, B.; Erwin, E.; Kerle, N.

    2009-04-01

    In case of emergency disaster managers worldwide require immediate information on affected areas and estimations of the number of affected people. Natural disasters such as earthquakes, hurricanes, tornados, wind and ice storms often involve failures in the electrical power generation system and grid. Near real time identification of power blackouts gives a first impression of the area affected by the event (Elvidge et al. 2007), which can subsequently be linked to population estimations. Power blackouts disrupt societal activities and compound the difficulties associated with search and rescue, clean up, and the provision of food and other supplies following a disastrous event. Locations and spatial extents of power blackouts are key considerations in planning and execution of the primary disaster missions of emergency management organizations. To date only one satellite data source has been used successfully for the detection of power blackouts. Operated by NOAA's National Geophysical Data Center (NGDC) the U.S. Air Force Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) offers a unique capability to observe lights present at the Earth's surface at night. Including a pair of visible and thermal spectral bands and originally designed to detect moonlit clouds, this sensor enables mapping of lights from cities and towns, gas flares and offshore platforms, fires, and heavily lit fishing boats. The low light imaging of the OLS is accomplished using a photomultiplier tube (PMT) which intensifies the visible band signal at night. With 14 orbits collected per day and a 3.000 km swath width, each OLS is capable of collecting a complete set of images of the Earth every 24 hours. NGDC runs the long-term archive for OLS data with the digital version extending back to 1992. OLS data is received by NGDC in near real time (1-2 hours from acquisition) and subscription based services for the near real time data are provided for users all over the

  8. AphasiaBank: Methods for Studying Discourse

    PubMed Central

    MacWhinney, Brian; Fromm, Davida; Forbes, Margaret; Holland, Audrey

    2011-01-01

    Background AphasiaBank is a computerized database of interviews between persons with aphasia (PWAs) and clinicians. By February 2011, the database had grown to include 145 PWAs and 126 controls from 12 sites across the United States. The data and related analysis programs are available free over the web. Aims The overall goal of AphasiaBank is the construction of a system for accumulating and sharing data on language usage by PWAs. To achieve this goal, we have developed a standard elicitation protocol and systematic automatic and manual methods for transcription, coding, and analysis. Methods & Procedures We present sample analyses of transcripts from the retelling of the Cinderella story. These analyses illustrate the application of our methods for the study of phonological, lexical, semantic, morphological, syntactic, temporal, prosodic, gestural, and discourse features. Main Contribution AphasiaBank will allow researchers access to a large, shared database that can facilitate hypothesis testing and increase methodological replicability, precision, and transparency. Conclusions AphasiaBank will provide researchers with an important new tool in the study of aphasia. PMID:22923879

  9. Relevance of the expression “obs stable” in nursing observations: retrospective study

    PubMed Central

    Vijayan, Roshan; Male, Pandora

    2011-01-01

    Objective To ascertain whether use of the term “obs stable” with respect to the nursing observations is so liberal as to render it meaningless. Design Retrospective study. Setting Three teaching hospitals in London, United Kingdom. Methods We searched progress notes for the current admission of 46 inpatients for entries containing the phrases “obs stable” and “observations stable,” and reviewed the nursing observations recorded during the 24 hour period preceding each entry containing at least one phrase. We calculated the frequency of abnormalities and of persistent abnormalities (defined as occurring in every observation) observed during these 24 hour periods, and the range of observation values over a 24 hour period if at least two observations had been recorded. Results We found at least one entry in 36 (78%) progress notes (95% confidence interval 66% to 90%). Observations in the 24 hours preceding an entry included at least one abnormality for 113 (71%) of 159 cases and at least one persistent abnormality for 31 (19%). The most frequently occurring abnormalities were tachypnoea (respiratory rate ≥20 breaths/min) and hypotension (systolic blood pressure <100 mm Hg). An abnormality occurred in the observations immediately preceding an entry in 42% of cases. Mean ranges of observations over 24 hours were within the limits of normal diurnal variation, although we found that some instances of greater than normal variability were described as “stable.” Conclusions The expression “obs stable” does not reliably indicate normal observations or variations in observations within physiological limits. Doctors should avoid using the expression altogether or clarify it with further information. PMID:22187323

  10. Case studies: Soil mapping using multiple methods

    NASA Astrophysics Data System (ADS)

    Petersen, Hauke; Wunderlich, Tina; Hagrey, Said A. Al; Rabbel, Wolfgang; Stümpel, Harald

    2010-05-01

    Soil is a non-renewable resource with fundamental functions like filtering (e.g. water), storing (e.g. carbon), transforming (e.g. nutrients) and buffering (e.g. contamination). Degradation of soils is meanwhile not only to scientists a well known fact, also decision makers in politics have accepted this as a serious problem for several environmental aspects. National and international authorities have already worked out preservation and restoration strategies for soil degradation, though it is still work of active research how to put these strategies into real practice. But common to all strategies the description of soil state and dynamics is required as a base step. This includes collecting information from soils with methods ranging from direct soil sampling to remote applications. In an intermediate scale mobile geophysical methods are applied with the advantage of fast working progress but disadvantage of site specific calibration and interpretation issues. In the framework of the iSOIL project we present here some case studies for soil mapping performed using multiple geophysical methods. We will present examples of combined field measurements with EMI-, GPR-, magnetic and gammaspectrometric techniques carried out with the mobile multi-sensor-system of Kiel University (GER). Depending on soil type and actual environmental conditions, different methods show a different quality of information. With application of diverse methods we want to figure out, which methods or combination of methods will give the most reliable information concerning soil state and properties. To investigate the influence of varying material we performed mapping campaigns on field sites with sandy, loamy and loessy soils. Classification of measured or derived attributes show not only the lateral variability but also gives hints to a variation in the vertical distribution of soil material. For all soils of course soil water content can be a critical factor concerning a succesful

  11. Large-Scale periodic solar velocities: An observational study

    NASA Technical Reports Server (NTRS)

    Dittmer, P. H.

    1977-01-01

    Observations of large-scale solar velocities were made using the mean field telescope and Babcock magnetograph of the Stanford Solar Observatory. Observations were made in the magnetically insensitive ion line at 5124 A, with light from the center (limb) of the disk right (left) circularly polarized, so that the magnetograph measures the difference in wavelength between center and limb. Computer calculations are made of the wavelength difference produced by global pulsations for spherical harmonics up to second order and of the signal produced by displacing the solar image relative to polarizing optics or diffraction grating.

  12. Creation of an ensemble of simulated cardiac cases and a human observer study: tools for the development of numerical observers for SPECT myocardial perfusion imaging

    NASA Astrophysics Data System (ADS)

    O'Connor, J. Michael; Pretorius, P. Hendrik; Gifford, Howard C.; Licho, Robert; Joffe, Samuel; McGuiness, Matthew; Mehurg, Shannon; Zacharias, Michael; Brankov, Jovan G.

    2012-02-01

    Our previous Single Photon Emission Computed Tomography (SPECT) myocardial perfusion imaging (MPI) research explored the utility of numerical observers. We recently created two hundred and eighty simulated SPECT cardiac cases using Dynamic MCAT (DMCAT) and SIMIND Monte Carlo tools. All simulated cases were then processed with two reconstruction methods: iterative ordered subset expectation maximization (OSEM) and filtered back-projection (FBP). Observer study sets were assembled for both OSEM and FBP methods. Five physicians performed an observer study on one hundred and seventy-nine images from the simulated cases. The observer task was to indicate detection of any myocardial perfusion defect using the American Society of Nuclear Cardiology (ASNC) 17-segment cardiac model and the ASNC five-scale rating guidelines. Human observer Receiver Operating Characteristic (ROC) studies established the guidelines for the subsequent evaluation of numerical model observer (NO) performance. Several NOs were formulated and their performance was compared with the human observer performance. One type of NO was based on evaluation of a cardiac polar map that had been pre-processed using a gradient-magnitude watershed segmentation algorithm. The second type of NO was also based on analysis of a cardiac polar map but with use of a priori calculated average image derived from an ensemble of normal cases.

  13. Social media methods for studying rare diseases.

    PubMed

    Schumacher, Kurt R; Stringer, Kathleen A; Donohue, Janet E; Yu, Sunkyung; Shaver, Ashley; Caruthers, Regine L; Zikmund-Fisher, Brian J; Fifer, Carlen; Goldberg, Caren; Russell, Mark W

    2014-05-01

    For pediatric rare diseases, the number of patients available to support traditional research methods is often inadequate. However, patients who have similar diseases cluster "virtually" online via social media. This study aimed to (1) determine whether patients who have the rare diseases Fontan-associated protein losing enteropathy (PLE) and plastic bronchitis (PB) would participate in online research, and (2) explore response patterns to examine social media's role in participation compared with other referral modalities. A novel, internet-based survey querying details of potential pathogenesis, course, and treatment of PLE and PB was created. The study was available online via web and Facebook portals for 1 year. Apart from 2 study-initiated posts on patient-run Facebook pages at the study initiation, all recruitment was driven by study respondents only. Response patterns and referral sources were tracked. A total of 671 respondents with a Fontan palliation completed a valid survey, including 76 who had PLE and 46 who had PB. Responses over time demonstrated periodic, marked increases as new online populations of Fontan patients were reached. Of the responses, 574 (86%) were from the United States and 97 (14%) were international. The leading referral sources were Facebook, internet forums, and traditional websites. Overall, social media outlets referred 84% of all responses, making it the dominant modality for recruiting the largest reported contemporary cohort of Fontan patients and patients who have PLE and PB. The methodology and response patterns from this study can be used to design research applications for other rare diseases.

  14. Why we need observational studies to evaluate the effectiveness of health care.

    PubMed Central

    Black, N.

    1996-01-01

    The view is widely held that experimental methods (randomised controlled trials) are the "gold standard" for evaluation and that observational methods (cohort and case control studies) have little or no value. This ignores the limitations of randomised trials, which may prove unnecessary, inappropriate, impossible, or inadequate. Many of the problems of conducting randomised trials could often, in theory, be overcome, but the practical implications for researchers and funding bodies mean that this is often not possible. The false conflict between those who advocate randomised trials in all situations and those who believe observational data provide sufficient evidence needs to be replaced with mutual recognition of the complementary roles of the two approaches. Researchers should be united in their quest for scientific rigour in evaluation, regardless of the method used. Images p1216-a PMID:8634569

  15. Helping Behaviors: An Observational Study of Preschool Children.

    ERIC Educational Resources Information Center

    Stockdale, Dahlia F.; And Others

    1989-01-01

    Examined the stability and circumstances of helping behaviors of 51 children of 41-69 months in a preschool classroom. Frequency of helping behaviors was not correlated with age or sex and was not stable over four 10-minute observation periods. Most helping acts were performed during nonimaginary play. (RJC)

  16. Sea ice climatology, variations and teleconnections: Observational and modeling studies

    NASA Astrophysics Data System (ADS)

    Liu, Jiping

    Hypotheses, models and observations suggest that sea ice plays an important role in the local, regional and global climate through a variety of processes across a full range of scales. However, our documentation and understanding of the nature of the polar-extrapolar climate teleconnections and their underlying causal and mechanistic links are still rudimentary, and the largest disagreements among model simulations of present and future climate are in the polar regions. In an effort to address these issues, we evaluated the simulated Antarctic sea ice variability and its climate teleconnections in three coupled global climate models (GISS, NCAR and GFDL) as compared to the observations. All the models capture the El Nino-Southern Oscillation (ENSO)-like phenomenon to some degree, although almost all the models miss some observed linkages. The GISS and NCAR models also capture the observed Antarctic Dipole and meridional banding structure through the Pacific. The Antarctic sea ice regions showing the strongest sensitivity to global teleconnections differ among the models and between the models and observations. We then proposed that the changes of the regional mean meridional atmospheric circulation (the regional Ferrel Cell) are one such mechanism leading to the covariability of the ENSO and Antarctic Dipole by modulating the mean meridional heat flux using the observational data. To more accurately represent sea ice simulations and associated feedbacks with the atmosphere and the ocean, the GISS coupled model was used to investigate the sensitivity of sea ice to the following physical parameterizations: (a) two sea ice dynamics (cavitating fluid and viscous-plastic), (b) the specification of oceanic isopyncal mixing coefficients in the Gent and McWillams isopyncal mixing, (c) the Wajsowicz viscosity diffusion, (d) surface albedo, (e) the penetration of solar radiation in sea ice, (f) effects of including a sea ice salinity budget, and (g) the ice-ocean boundary

  17. Critical Illness Outcome Study: An Observational Study on Protocols and Mortality in Intensive Care Units

    PubMed Central

    Ali, Naeem A.; Gutteridge, David; Shahul, Sajid; Checkley, William; Sevransky, Jonathan; Martin, Greg S.

    2014-01-01

    Introduction Many individual Intensive Care Unit (ICU) characteristics have been associated with patient outcomes, including staffing, expertise, continuity and team structure. Separately, many aspects of clinical care in ICUs have been operationalized through the development of complex treatment protocols. The United State Critical Illness and Injury Trials Group-Critical Illness Outcomes Study (USCIITG-CIOS) was designed to determine whether the extent of protocol availability and use in ICUs is associated with hospital survival in a large cohort of United States ICUs. Here, we describe the study protocol and analysis plan approved by the USCIITG-CIOS Steering Committee. Methods USCIITG-CIOS is a prospective, observational, ecological multi-centered “cohort” study of mixed ICUs in the U.S. The data collected include organizational information for the ICU (e.g., protocol availability and utilization, multi-disciplinary staffing assessment) and patient level information (e.g. demographics, acute and chronic medical conditions). The primary outcome is all-cause hospital mortality, with the objective being to determine whether there is an association between protocol number and hospital mortality for ICU patients. USCIITG-CIOS is powered to detect a 3% difference in crude hospital mortality between high and low protocol use ICUs, dichotomized according to protocol number at the median. The analysis will utilize regression modeling to adjust for outcome clustering by ICU, with secondary linear analysis of protocol number and mortality and a variety of a priori planned ancillary studies. There are presently 60 ICUs participating in USCIITG-CIOS to enroll approximately 6,000 study subjects. Conclusions USCIITG-CIOS is a large multicentric study examining the effect of ICU protocol use on patient outcomes. The primary results of this study will inform our understanding of the relationship between protocol availability, use, and patient outcomes in the ICU. Moreover

  18. Mass changes of microparticles in a plasma observed by a phase-resolved resonance method

    SciTech Connect

    Carstensen, Jan; Jung, Hendrik; Greiner, Franko; Piel, Alexander

    2011-03-15

    The influence of a plasma environment on melamine formaldehyde particles is studied. High-precision measurements of the vertical confinement frequency with a phase-resolved resonance method indicate that the particle mass is affected in two ways: the deposition of sputtered material at the particle leads to a mass gain, whereas the outgassing of water causes a mass loss.

  19. Mass changes of microparticles in a plasma observed by a phase-resolved resonance method

    NASA Astrophysics Data System (ADS)

    Carstensen, Jan; Jung, Hendrik; Greiner, Franko; Piel, Alexander

    2011-03-01

    The influence of a plasma environment on melamine formaldehyde particles is studied. High-precision measurements of the vertical confinement frequency with a phase-resolved resonance method indicate that the particle mass is affected in two ways: the deposition of sputtered material at the particle leads to a mass gain, whereas the outgassing of water causes a mass loss.

  20. 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

  1. Orbital Roulette: A New Method of Gravity Estimation from Observed Motions

    NASA Astrophysics Data System (ADS)

    Beloborodov, Andrei M.; Levin, Yuri

    2004-09-01

    The traditional way of estimating the gravitational field from observed motions of test objects is based on the virial relation between their kinetic and potential energy. We find a more efficient method. It is based on the natural presumption that the objects are observed at a random moment of time and therefore have random orbital time phases. The proposed estimator, which we call ``orbital roulette,'' checks the randomness of the phases. The method has the following advantages: (1) It accurately estimates Keplerian (point-mass) potentials as well as non-Keplerian potentials, where the unknown gravitating mass is distributed in space. (2) It is a complete statistical estimator: it checks a trial potential and accepts it or rules it out with a certain significance level; the best-fit measurement is thus supplemented with error bars at any confidence level. (3) It needs no a priori assumptions about the distribution of orbital parameters of the test bodies. We test our estimator with Monte Carlo-generated motions and demonstrate its efficiency. Useful applications include the Galactic Center, dark-matter halo of the Galaxy, and clusters of stars or galaxies.

  2. A new modelling method for non-convex shapes of asteroids based on photometric observations

    NASA Astrophysics Data System (ADS)

    Bartczak, P.; Santana-Ros, T.; Marciniak, A.; Michałowski, T.; Prętka-Ziomek, H.

    2014-04-01

    We present the new SAGE algorithm (Shaping Asteroids with Genetic Evolution) able to derive 3-D nonconvex shapes of asteroids and solving for their spin parameters using only disk-integrated photometry. A triangular mesh of 62 vertices is used as a seed during the parameters minimization, and the Catmull-Clark method is applied to generate bodies with higher resolution. The subroutines search for the sidereal period of rotation in a given range, and the spin axis orientation on the whole celestial sphere. A step-iterative algorithm is used to make the shape evolve under the minimization constrains between the synthetic generated photometry and the real observations. In order to generate the simulated lightcurves we propose the virtual frames algorithm. The algorithm simulates the pictures visible on hypothetical CCD frames and, using only elementary vector operations or quadratic algebraic equations, it takes into account all phase angle effects. Publicly available lightcurve data has been used to obtain a new non-convex model for (9) Metis and (433) Eros. The resulting body shapes are compared with the ones obtained using other observational techniques, such as adaptive optics and stellar occultations (for Metis) or the NEAR Shoemaker observations of Eros during its rendezvous.

  3. 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

  4. An Unroofing Method to Observe the Cytoskeleton Directly at Molecular Resolution Using Atomic Force Microscopy.

    PubMed

    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

  5. Integrating patient teaching into bedside patient care: a participant-observation study of hospital nurses.

    PubMed

    Barber-Parker, Elaine D

    Today's patients are quickly discharged from hospitals and often continue complex treatments at home. Patient teaching is critical and hospital nurses are encouraged to use "every teachable moment." This study explored and described the nature of integrating patient teaching into daily patient care and the factors influencing the delivery of teaching. A fieldwork method, conducted over 12 months, used participant-observation (PO) and a focus group session to answer the research questions. Three experienced registered nurses working on the oncology unit of an acute care community hospital served as informants. Critical attributes and patterns of observed teaching events were described.

  6. Observational and theoretical studies of the nova outburst

    SciTech Connect

    Starrfield, S.; Vanlandingham, K.; Schwarz, G.

    1998-04-01

    A nova outburst is one consequence of the accretion of hydrogen rich material onto a white dwarf in a close binary system. The strong electron degeneracy of a massive white dwarf drives the temperatures in the nuclear burning region to values exceeding 108K under all circumstances. As a result, a major fraction of the CNO nuclei in the envelope are transformed into e{sup +}-decay nuclei, which constrains the nuclear energy generation and yields non-solar CNO isotopic abundance ratios. In addition, the observations demonstrate that white dwarf core material is dredged up into the accreted layers and these nuclei are the catalysts for producing peak rates of energy generation that can exceed 10{sup 16} erg gm{sup -1}s{sup -1}. Observations show that there are two compositional classes of novae, one that occurs on a carbon-oxygen white dwarf and the other that occurs on an oxygen-neon-magnesium white dwarf.

  7. [Gastric magnetic resonance study (methods, semiotics)].

    PubMed

    Stashuk, G A

    2003-01-01

    The paper shows the potentialities of gastric study by magnetic resonance imaging (MRI). The methodic aspects of gastric study have been worked out. The MRI-semiotics of the unchanged and tumor-affected wall of the stomach and techniques in examining patients with gastric cancer of various sites are described. Using the developed procedure, MRI was performed in 199 patients, including 154 patients with gastric pathology and 45 control individuals who had no altered gastric wall. Great emphasis is placed on the role of MRI in the diagnosis of endophytic (diffuse) gastric cancer that is of priority value in its morphological structure. MRI was found to play a role in the diagnosis of the spread of a tumorous process both along the walls of the stomach and to its adjacent anatomic structures.

  8. Observations on ion track structure in semiconductors : a phenomenological study

    NASA Technical Reports Server (NTRS)

    Selva, L. E.; Wallace, R. E.

    2001-01-01

    An ion track structure model at the nanometer scale is presented. The model is based on electrostatic principles and is supported by observed experimental results conducted on power MOSFETs. The model predicts the existence of a transient induced electric field following the passage of an energetic heavy ion. There are two segments to the field (a radial and an axial component). It is the interaction of this transient electric field with the local environment that can trigger a catastrophic failure.

  9. Observational learning in chimpanzees and children studied through 'ghost' conditions.

    PubMed

    Hopper, Lydia M; Lambeth, Susan P; Schapiro, Steven J; Whiten, Andrew

    2008-04-01

    Emulation has been distinguished from imitation as a form of observational learning because it focuses not on the model's actions but on the action's environmental results. Whether a species emulates, imitates or displays only simpler observational learning is expected to have profound implications for its capacity for cultural transmission. Chimpanzees' observational learning has been suggested to be primarily emulative, but this is an inference largely based upon low fidelity copying in experiments when comparing chimpanzees with humans rather than direct testing. Here we test directly for emulation learning by chimpanzees and children using a 'ghost' condition in which a sliding door obscuring a reward was moved to left or right with no agent visible, a context associated with the only published evidence for emulation learning in a non-human species (pigeons). Both children and chimpanzees matched the observed direction of ghost door movement on their first test trial. This is the first evidence for emulation in a non-human primate in the restricted context of a ghost condition. However, only the children continued to match in later trials. Individuals of both species continued to match with 99% or better fidelity when viewing a conspecific model operates the door. We conclude that chimpanzees can and will display emulation learning when the task is as simple as the present one, which contrasts with a failure to do so in a more complex manipulative task tested earlier. However, even with a simple task, emulation alone creates only fleeting fidelity compared with the opportunity to copy a conspecific, when considerable conformity is displayed.

  10. Aerosol properties from 4STAR observations: A sensitivity study

    NASA Astrophysics Data System (ADS)

    Kassianov, E.; Flynn, C.; Redemann, J.; Livingston, J. M.; Schmid, B.; Russell, P. B.; Sinyuk, A.

    2011-12-01

    Multi-spectral direct-beam observations of atmospheric aerosol and gas constituents have been taken successfully at a number of sites around the world by the airborne 14-Channel NASA Ames Airborne Tracking Sunphotometer (AATS-14). The recently developed airborne Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR) is the next generation of AATS-14 with ultraviolet, visible and near-infrared spectral coverage, increased number of channels (more than 1500 pixels) and the sky-scanning ability of the ground-based AERONET sun/sky photometers. While it is generally agreed that more measurements in terms of independent wavelengths and scattering angles would offer enhanced aerosol retrievals, the potential afforded by improved observational capabilities of the 4STAR has not yet been fully characterized. This paper will attempt to place the importance of improved spectrally- and angularly-resolved 4STAR observations within the context of the well-known AERONET intensive-property retrieval. In particular, we have developed model data sets comparable to the 4STAR measurements of direct sun and sky radiances and evaluated the impact on the retrieval from subsampling in wavelength and scattering angle.

  11. CSM research: Methods and application studies

    NASA Technical Reports Server (NTRS)

    Knight, Norman F., Jr.

    1989-01-01

    Computational mechanics is that discipline of applied science and engineering devoted to the study of physical phenomena by means of computational methods based on mathematical modeling and simulation, utilizing digital computers. The discipline combines theoretical and applied mechanics, approximation theory, numerical analysis, and computer science. Computational mechanics has had a major impact on engineering analysis and design. When applied to structural mechanics, the discipline is referred to herein as computational structural mechanics. Complex structures being considered by NASA for the 1990's include composite primary aircraft structures and the space station. These structures will be much more difficult to analyze than today's structures and necessitate a major upgrade in computerized structural analysis technology. NASA has initiated a research activity in structural analysis called Computational Structural Mechanics (CSM). The broad objective of the CSM activity is to develop advanced structural analysis technology that will exploit modern and emerging computers, such as those with vector and/or parallel processing capabilities. Here, the current research directions for the Methods and Application Studies Team of the Langley CSM activity are described.

  12. Arctic stratospheric dehydration - Unprecedented observations and microphysical modeling study

    NASA Astrophysics Data System (ADS)

    Engel, Ines; Luo, Beiping P.; Khaykin, Sergey; Wienhold, Frank G.; Vömel, Holger; Kivi, Rigel; Pitts, Michael C.; Poole, Lamont R.; Santee, Michelle L.; Grooß, Jens-Uwe; Peter, Thomas

    2013-04-01

    Polar stratospheric clouds (PSCs) may form in the lower stratosphere above the winter poles at sufficiently low temperatures. Ice PSCs require the coldest conditions, with temperatures some degrees below the frost point to nucleate ice particles. When the particles grow to sizes large enough to sediment, they may result in dehydration, i.e. irreversible redistribution of water vapor, as it frequently occurs above the Antarctic. Conversely, there are no observations above the Arctic that would have provided clear evidence for vertical redistribution of water vapor. Here we report on unequivocal in situ observations in January 2010 above Sodankylä, Finland, which mesh with vortex-wide satellite measurements. Within the LABPIAT-II field campaign, a series of balloon-borne aerosol backscatter and water vapor measurements has been performed. The balloon payload comprised the backscatter sonde COBALD in combination with the cryogenic frost point hygrometer CFH and the fluorescent Lyman-Alpha stratospheric hygrometer FLASH-B. Together with satellite measurements from the Aura microwave limb sounder MLS and the cloud-aerosol lidar CALIOP, a unique and coherent picture of de- and rehydration in the Arctic vortex will be presented within this paper. An extensive coverage of synoptic scale ice PSCs has been observed by CALIOP and COBALD by mid-January due to exceptionally low temperatures in the Arctic vortex. This observation goes along with a simultaneously measured strong reduction in water vapor by 1.6 ppmv relative to background conditions. Subsequent sedimentation and sublimation of ice particles led to a vertical redistribution of water inside the vortex, which was tracked remotely and could be quantified again by in situ measurements some five days later. By means of a microphysical column model, we are able to connect the individual balloon soundings by trajectories and simulate the formation, evolution and sedimentation of the ice particles. Simulated water vapor

  13. Numerical spherical aberration correction method using spatial light modulator under deep-part fluorescence observation

    NASA Astrophysics Data System (ADS)

    Takiguchi, Yu; Takamoto, Hisayoshi; Kanada, Masamitsu; Inoue, Takashi; Matsumoto, Naoya; Terakawa, Susumu

    2014-03-01

    We have developed a confocal fluorescence laser scanning microscopy (CFLSM) incorporating a liquid crystal on silicon spatial light modulator (LCOS-SLM). To achieve high-resolution and high-contrast imaging for deeper part of the tissue with CFLSM, high numerical aperture objective lenses are required to tightly focus excitation light to meet Rayleigh limit(criterion) for the specimens. However, mismatch of refractive index at the boundary of interfacing materials, such as atmosphere, glass cover, and biological tissues, causes spherical aberration. Recently, we proposed a numerical method for correcting spherical aberration. In this method a pre-distorted wavefront pattern for aberration correction is calculated by ray tracing from a hypothetical focal point inside a specimen to the pupil plane. The resulting microscope can correct such spherical aberration. We observed 6.0μm fluorescent micro-beads dispersed three-dimensionally in agarose gel to confirm effectiveness of aberration correction. We reconstructed a three-dimensional image by taking 20 images by changing the depth with 1 μm interval and stacking them. It was apparent that the longitudinal/depth resolution was improved and that the intensity of fluorescence image was increased with aberration correction. While this method is applicable to other laser scanning microscopes, it has potential to enhance the signals for various super-resolution microscopic techniques, such as stimulated- emission-depletion (STED) fluorescence microscopy.

  14. A fast method for quantifying observational selection effects in asteroid surveys

    NASA Astrophysics Data System (ADS)

    Jedicke, Robert; Bolin, Bryce; Granvik, Mikael; Beshore, Ed

    2016-03-01

    We present a fast method to calculate an asteroid survey's 'bias' - essentially a correction factor from the observed number of objects to the actual number in the population. The method builds upon the work of Jedicke and Metcalfe (Jedicke, R., Metcalfe, T.S. [1998]. Icaurs 131, 245-260) and Granvik et al. (Granvik, M., Vaubaillon, J., Jedicke, R. [2012]. Icarus 218, 262-277) and essentially efficiently maps out the phase space of orbit elements that can appear in a field-of-view. It does so by 'integrating' outwards in geocentric distance along a field's boresite from the topocentric location of the survey and calculating the allowable angular elements for each desired combination of semi-major axis, eccentricity and inclination. We then use a contour algorithm to map out the orbit elements that place an object at the edge of the field-of-view. We illustrate the method's application to calculate the bias correction for near Earth Objects detected with the Catalina Sky Survey (Christensen, E. et al. [2012]. AAS/Division for Planetary Sciences Meeting Abstracts, vol. 44, p. 210.13; Larson, S. et al. [1998]. Bulletin of the American Astronomical Society, vol. 30, p. 1037).

  15. A comparison of reconstruction methods for the estimation of coronal mass ejections kinematics based on SECCHI/HI observations

    SciTech Connect

    Mishra, Wageesh; Srivastava, Nandita; Davies, Jackie A.

    2014-04-01

    A study of the kinematics and arrival times of coronal mass ejections (CMEs) at Earth, derived from time-elongation maps (J-maps) constructed from STEREO/heliospheric imager (HI) observations, provides an opportunity to understand the heliospheric evolution of CMEs in general. We implement various reconstruction techniques, based on the use of time-elongation profiles of propagating CMEs viewed from single or multiple vantage points, to estimate the dynamics of three geo-effective CMEs. We use the kinematic properties, derived from analysis of the elongation profiles, as inputs to the Drag Based Model for the distance beyond which the CMEs cannot be tracked unambiguously in the J-maps. The ambient solar wind into which these CMEs, which travel with different speeds, are launched, is different. Therefore, these CMEs will evolve differently throughout their journey from the Sun to 1 AU. We associate the CMEs, identified and tracked in the J-maps, with signatures observed in situ near 1 AU by the WIND spacecraft. By deriving the kinematic properties of each CME, using a variety of existing methods, we assess the relative performance of each method for the purpose of space weather forecasting. We discuss the limitations of each method, and identify the major constraints in predicting the arrival time of CMEs near 1 AU using HI observations.

  16. 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.

  17. Structural methods for studying IRES function.

    PubMed

    Kieft, Jeffrey S; Costantino, David A; Filbin, Megan E; Hammond, John; Pfingsten, Jennifer S

    2007-01-01

    Internal ribosome entry sites (IRESs) substitute RNA sequences for some or all of the canonical translation initiation protein factors. Therefore, an important component of understanding IRES function is a description of the three-dimensional structure of the IRES RNA underlying this mechanism. This includes determining the degree to which the RNA folds, the global RNA architecture, and higher resolution information when warranted. Knowledge of the RNA structural features guides ongoing mechanistic and functional studies. In this chapter, we present a roadmap to structurally characterize a folded RNA, beginning from initial studies to define the overall architecture and leading to high-resolution structural studies. The experimental strategy presented here is not unique to IRES RNAs but is adaptable to virtually any RNA of interest, although characterization of RNA-protein interactions requires additional methods. Because IRES RNAs have a specific function, we present specific ways in which the data are interpreted to gain insight into that function. We provide protocols for key experiments that are particularly useful for studying IRES RNA structure and that provide a framework onto which additional approaches are integrated. The protocols we present are solution hydroxyl radical probing, RNase T1 probing, native gel electrophoresis, sedimentation velocity analytical ultracentrifugation, and strategies to engineer RNA for crystallization and to obtain initial crystals. PMID:17913644

  18. Methods and software for cosmic ray scintillation studies

    NASA Technical Reports Server (NTRS)

    Gulinsky, O. V.; Dorman, L. I.; Prilutsky, R. E.

    1985-01-01

    The principal instrument used in cosmic ray scintillation studies is the spectra constructed from intensive observation. This method has its drawbacks in that the statistical characteristics of the process undergo essential reconstruction, i.e., the process becomes nonstationary from the viewpoint of such phenomena as Forbush decrease and during solar flares. The software used to process the above includes the direct Fourier transform and its modifications, autoregressive processes, and instantaneous spectrum methods. Used in various combinations, they prove helpful in handling the time series.

  19. Observations on studies useful to asbestos operations and management activities

    SciTech Connect

    Wilmoth, R.C.; Powers, T.J.; Millette, J.R.

    1991-01-01

    Asbestos-containing materials found in buildings may release asbestos fibers into the air. Some of these fibers will eventually settle and attach to room surfaces (walls, furnishings, equipment, floors, and carpet) as part of normal dust. Activities like dusting, sweeping and vacuuming are likely to re-entrain the dust causing exposure to airborne asbestos. The paper discusses data that are largely observational in nature, but are illustrative of general trends of interest to those individuals dealing with the day-to-day problems of asbestos in buildings.

  20. [Temporal sequence in observational studies to establish causality].

    PubMed

    Silva, Luis Carlos

    2014-05-02

    The article includes a brief summary on the scope of the notions of causality and risk and considers some operational difficulties that arise when dealing with problems associated with them. It underscores the vital importance of timing and its link with the most commonly used observational research designs that address causal relationships. The article describes in detail the need to record the order in which the relevant events occur and how to consider this in the analysis. A detailed example of errors that are usually incurred in and their effect is provided.

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

    PubMed Central

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

    2011-01-01

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

  2. Experimental and observational studies in ultraviolet space astronomy

    NASA Astrophysics Data System (ADS)

    Ohl, Raymond George, IV

    2000-12-01

    This work covers the far-ultraviolet (FUV; 900-1200 Å) imaging performance of telescope mirrors for the Far Ultraviolet Spectroscopic Explorer (FUSE) and presents Ultraviolet Imaging Telescope (UIT) observations of early-type galaxies (1550 Å) and FUSE spectra of a subdwarf B star and two O7 supergiants. FUSE Mirror Imaging Performance. The imaging performance of optics at short wavelengths (UV-X-ray) is dependent on figure quality and small-scale surface roughness. We developed a novel interferometric alignment technique for off-axis parabolic mirrors used for laboratory testing. During mirror assembly, we investigated and mitigated mount- related distortions which contributed to figure error. We performed extensive metrology, image testing and analysis to predict the on-orbit, FUV point spread function. The FUSE mirrors meet mission imaging requirements. UIT Observations of Early-Type Galaxies. Early UV space astronomy missions revealed that early-type galaxies harbor a population of stars with effective temperatures greater than that of the main sequence turn-off (~6,000 K) and UV emission that is very sensitive to characteristics of the stellar population. We present UV (1550 Å) surface photometry and UV-B color profiles for 8 E and S0 galaxies observed by UIT. Some objects have de Vaucouleurs surface brightness profiles, while others have disk-like profiles, but we find no other evidence for the presence of a disk or young, massive stars. There is a wide range of UV-B color gradients, but there is no correlation with metallicity gradients. Analysis of the FUSE Spectrum of a Subdwarf B Star. Subdwarf B (sdB) stars are the leading candidate UV emitters in old, high metallicity stellar populations (e.g., early-type galaxies). We observed the Galactic sdB star PG0749+658 with FUSE and derived abundances with the aim of constraining models of the heavy element distribution in sdB atmospheres. All of the elements measured are depleted with respect to solar

  3. A dynamic scheduling method of Earth-observing satellites by employing rolling horizon strategy.

    PubMed

    Dishan, Qiu; Chuan, He; Jin, Liu; Manhao, Ma

    2013-01-01

    Focused on the dynamic scheduling problem for earth-observing satellites (EOS), an integer programming model is constructed after analyzing the main constraints. The rolling horizon (RH) strategy is proposed according to the independent arriving time and deadline of the imaging tasks. This strategy is designed with a mixed triggering mode composed of periodical triggering and event triggering, and the scheduling horizon is decomposed into a series of static scheduling intervals. By optimizing the scheduling schemes in each interval, the dynamic scheduling of EOS is realized. We also propose three dynamic scheduling algorithms by the combination of the RH strategy and various heuristic algorithms. Finally, the scheduling results of different algorithms are compared and the presented methods in this paper are demonstrated to be efficient by extensive experiments.

  4. Comparison of direct observational methods for measuring stereotypic behavior in children with autism spectrum disorders.

    PubMed

    Gardenier, Nicole Ciotti; MacDonald, Rebecca; Green, Gina

    2004-01-01

    We compared partial-interval recording (PIR) and momentary time sampling (MTS) estimates against continuous measures of the actual durations of stereotypic behavior in young children with autism or pervasive developmental disorder-not otherwise specified. Twenty-two videotaped samples of stereotypy were scored using a low-tech duration recording method, and relative durations (i.e., proportions of observation periods consumed by stereotypy) were calculated. Then 10, 20, and 30s MTS and 10s PIR estimates of relative durations were derived from the raw duration data. Across all samples, PIR was found to grossly overestimate the relative duration of stereotypy. Momentary time sampling both over- and under-estimated the relative duration of stereotypy, but with much smaller errors than PIR (Experiment 1). These results were replicated across 27 samples of low, moderate and high levels of stereotypy (Experiment 2).

  5. Development of a Method for the Observation of Lightning in Protoplanetary Disks Using Ion Lines

    NASA Astrophysics Data System (ADS)

    Muranushi, Takayuki; Akiyama, Eiji; Inutsuka, Shu-ichiro; Nomura, Hideko; Okuzumi, Satoshi

    2015-12-01

    In this paper, we propose observational methods for detecting lightning in protoplanetary disks. We do so by calculating the critical electric field strength in the lightning matrix gas (LMG), the parts of the disk where the electric field is strong enough to cause lightning. That electric field accelerates multiple positive ion species to characteristic terminal velocities. In this paper, we present three distinct discharge models with corresponding critical electric fields. We simulate the position-velocity diagrams and the integrated emission maps for the models. We calculate the measure-of-sensitivity values for detection of the models and for distinguishing between the models. At the distance of TW Hya (54 pc), LMG that occupies 2π in azimuth and has 25 AU < r < 50 AU is detectable at 1200σ to 4000σ. The lower limits of the radii of 5σ-detectable LMG clumps are between 1.6 AU and 5.3 AU, depending on the models.

  6. Floating Silicon Method single crystal ribbon - observations and proposed limit cycle theory

    NASA Astrophysics Data System (ADS)

    Kellerman, Peter; Kernan, Brian; Helenbrook, Brian T.; Sun, Dawei; Sinclair, Frank; Carlson, Frederick

    2016-10-01

    In the Floating Silicon Method (FSM), a single-crystal Si ribbon is grown while floating on the surface of a Si melt. In this paper, we describe the phenomenology of FSM, including the observation of approximately regularly spaced "facet lines" on the ribbon surface whose orientation aligns with (111) crystal planes. Sb demarcation experiments sectioned through the thickness of the ribbon reveal that the solid/melt interface consists of dual (111) planes and that the leading edge facet growth is saccadic in nature, rather than steady-state. To explain this behavior, we propose a heuristic solidification limit cycle theory, using a continuum level of description with anisotropic kinetics as developed by others, and generalizing the interface kinetics to include a roughening transition as well as a re-faceting mechanism that involves curvature and the Gibbs-Thomson effect.

  7. Reverse Discrimination by Minority Groups. A Participant Observation Study.

    ERIC Educational Resources Information Center

    Clavner, Jerry B.; Clavner, Catherine

    This study explores reverse discrimination as a cultural phenomenon that should be studied by anthropologists, and to which anthropology has inadvertently contributed. Discrimination by minority group members is taught and encouraged under the guise of ethnic pride and promotion of traditional beliefs. Ethnocentrism may be a cultural defense…

  8. Active commuting to elementary school and adiposity: An observational study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Active commuting to school (ACS; walking or cycling to school) appears promising for decreasing children's obesity risk, although long-term studies are sparse. The aim was to examine whether kindergarten ACS was associated with fifth grade adiposity. This study was a secondary analysis of the Early ...

  9. Theoretical and Observational Studies of the Central Engines of AGN

    NASA Technical Reports Server (NTRS)

    Sivron, Ran

    1995-01-01

    In Active Galactic Nuclei (AGN) the luminosity is so intense that the effect of radiation pressure on a particle may exceed the gravitational attraction. It was shown that when such luminosities are reached, relatively cold (not completely ionized) thermal matter clouds may form in the central engines of AGN, where most of the luminosity originates. We show that the spectrum of emission from cold clouds embedded in hot relativistic matter is similar to the observed spectrum. We also show that within the hot relativistic matter, cold matter moves faster than the speed of sound or the Alfven speed, and shocks form. The shocks provide a mechanism by which a localized perturbation can propagate throughout the central engine. The shocked matter can emit the observed luminosity, and can explain the flux and spectral variability. It may also provide an efficient mechanism for the outward transfer of angular momentum and provide the outward flow of winds. With observations from X-ray satellites, emission features from the cold and hot matter may be revealed. Our analysis of X-ray data from the Seyfert 1 galaxy MCG - 6-30-15 over five years using detectors on the Ginga and Rosat satellites, revealed some interesting variable features. A source with hot matter emits non-thermal radiation which is Compton reflected from cold matter and then absorbed by warm (partially ionized) absorbing matter in the first model, which can be fit to the data if both the cold and warm absorbers are near the central engine. An alternative model in which the emission from the hot matter is partially covered by very warm matter (in which all elements except Iron are mostly ionized) is also successful. In this model the cold and warm matter may be at distances of up to 100 times the size of the central engine, well within the region where broad optical lines are produced. The flux variability is more naturally explained by the second model. Our results support the existence of cold matter in, or

  10. Computational methods for inverse problems in geophysics: inversion of travel time observations

    USGS Publications Warehouse

    Pereyra, V.; Keller, H.B.; Lee, W.H.K.

    1980-01-01

    General ways of solving various inverse problems are studied for given travel time observations between sources and receivers. These problems are separated into three components: (a) the representation of the unknown quantities appearing in the model; (b) the nonlinear least-squares problem; (c) the direct, two-point ray-tracing problem used to compute travel time once the model parameters are given. Novel software is described for (b) and (c), and some ideas given on (a). Numerical results obtained with artificial data and an implementation of the algorithm are also presented. ?? 1980.

  11. Modelling non-Gaussianity of background and observational errors by the Maximum Entropy method

    NASA Astrophysics Data System (ADS)

    Pires, Carlos; Talagrand, Olivier; Bocquet, Marc

    2010-05-01

    The Best Linear Unbiased Estimator (BLUE) has widely been used in atmospheric-oceanic data assimilation. However, when data errors have non-Gaussian pdfs, the BLUE differs from the absolute Minimum Variance Unbiased Estimator (MVUE), minimizing the mean square analysis error. The non-Gaussianity of errors can be due to the statistical skewness and positiveness of some physical observables (e.g. moisture, chemical species) or due to the nonlinearity of the data assimilation models and observation operators acting on Gaussian errors. Non-Gaussianity of assimilated data errors can be justified from a priori hypotheses or inferred from statistical diagnostics of innovations (observation minus background). Following this rationale, we compute measures of innovation non-Gaussianity, namely its skewness and kurtosis, relating it to: a) the non-Gaussianity of the individual error themselves, b) the correlation between nonlinear functions of errors, and c) the heteroscedasticity of errors within diagnostic samples. Those relationships impose bounds for skewness and kurtosis of errors which are critically dependent on the error variances, thus leading to a necessary tuning of error variances in order to accomplish consistency with innovations. We evaluate the sub-optimality of the BLUE as compared to the MVUE, in terms of excess of error variance, under the presence of non-Gaussian errors. The error pdfs are obtained by the maximum entropy method constrained by error moments up to fourth order, from which the Bayesian probability density function and the MVUE are computed. The impact is higher for skewed extreme innovations and grows in average with the skewness of data errors, especially if those skewnesses have the same sign. Application has been performed to the quality-accepted ECMWF innovations of brightness temperatures of a set of High Resolution Infrared Sounder channels. In this context, the MVUE has led in some extreme cases to a potential reduction of 20-60% error

  12. Atmospheric correction of Earth-observation remote sensing images by Monte Carlo method

    NASA Astrophysics Data System (ADS)

    Hadjit, Hanane; Oukebdane, Abdelaziz; Belbachir, Ahmad Hafid

    2013-10-01

    In earth observation, the atmospheric particles contaminate severely, through absorption and scattering, the reflected electromagnetic signal from the earth surface. It will be greatly beneficial for land surface characterization if we can remove these atmospheric effects from imagery and retrieve surface reflectance that characterizes the surface properties with the purpose of atmospheric correction. Giving the geometric parameters of the studied image and assessing the parameters describing the state of the atmosphere, it is possible to evaluate the atmospheric reflectance, and upward and downward transmittances which take part in the garbling data obtained from the image. To that end, an atmospheric correction algorithm for high spectral resolution data over land surfaces has been developed. It is designed to obtain the main atmospheric parameters needed in the image correction and the interpretation of optical observations. It also estimates the optical characteristics of the Earth-observation imagery (LANDSAT and SPOT). The physics underlying the problem of solar radiation propagations that takes into account multiple scattering and sphericity of the atmosphere has been treated using Monte Carlo techniques.

  13. Wake Study Methods of Wind Turbines

    NASA Astrophysics Data System (ADS)

    Suatean, Bogdan; Colidiuc, Alexandra; Galetuse, Stelian; Frunzulica, Florin

    2011-09-01

    Two different methods for determination of the aerodynamic performance of horizontal axis wind turbines (HAWT) are proposed in this paper. The methods presented have various levels of complexity to calculate the aerodynamic performances of HAWT, starting with a simple method, the lifting line method, and ending with a CFD approach.

  14. Observer assessment of multi-pinhole SPECT geometries for prostate cancer imaging: a simulation study

    NASA Astrophysics Data System (ADS)

    Kalantari, Faraz; Sen, Anando; Gifford, Howard C.

    2014-03-01

    SPECT imaging using In-111 ProstaScint is an FDA-approved method for diagnosing prostate cancer metastases within the pelvis. However, conventional medium-energy parallel-hole (MEPAR) collimators produce poor image quality and we are investigating the use of multipinhole (MPH) imaging as an alternative. This paper presents a method for evaluating MPH designs that makes use of sampling-sensitive (SS) mathematical model observers for tumor detectionlocalization tasks. Key to our approach is the redefinition of a normal (or background) reference image that is used with scanning model observers. We used this approach to compare different MPH configurations for the task of small-tumor detection in the prostate and surrounding lymph nodes. Four configurations used 10, 20, 30, and 60 pinholes evenly spaced over a complete circular orbit. A fixed-count acquisition protocol was assumed. Spherical tumors were placed within a digital anthropomorphic phantom having a realistic Prostascint biodistribution. Imaging data sets were generated with an analytical projector and reconstructed volumes were obtained with the OSEM algorithm. The MPH configurations were compared in a localization ROC (LROC) study with 2D pelvic images and both human and model observers. Regular and SS versions of the scanning channelized nonprewhitening (CNPW) and visual-search (VS) model observers were applied. The SS models demonstrated the highest correlations with the average human-observer results

  15. Study on individual stochastic model of GNSS observations for precise kinematic applications

    NASA Astrophysics Data System (ADS)

    Próchniewicz, Dominik; Szpunar, Ryszard

    2015-04-01

    The proper definition of mathematical positioning model, which is defined by functional and stochastic models, is a prerequisite to obtain the optimal estimation of unknown parameters. Especially important in this definition is realistic modelling of stochastic properties of observations, which are more receiver-dependent and time-varying than deterministic relationships. This is particularly true with respect to precise kinematic applications which are characterized by weakening model strength. In this case, incorrect or simplified definition of stochastic model causes that the performance of ambiguity resolution and accuracy of position estimation can be limited. In this study we investigate the methods of describing the measurement noise of GNSS observations and its impact to derive precise kinematic positioning model. In particular stochastic modelling of individual components of the variance-covariance matrix of observation noise performed using observations from a very short baseline and laboratory GNSS signal generator, is analyzed. Experimental test results indicate that the utilizing the individual stochastic model of observations including elevation dependency and cross-correlation instead of assumption that raw measurements are independent with the same variance improves the performance of ambiguity resolution as well as rover positioning accuracy. This shows that the proposed stochastic assessment method could be a important part in complex calibration procedure of GNSS equipment.

  16. An Observational and Theoretical Study of Highly Supercooled Altocumulus.

    NASA Astrophysics Data System (ADS)

    Heymsfield, Andrew J.; Miloshevich, Larry M.; Slingo, Anthony; Sassen, Kenneth; O'C. Starr, David

    1991-04-01

    Two altocumulus clouds, which formed at a temperature of 30°C, were sampled using the NCAR King Air aircraft and coincident lidar during the 1986 FIRE cirrus experiment in Wisconsin. The clouds were structurally and thermodynamically similar to stratocumulus, with extensive cloudtop entrainment, a capping temperature inversion, and a dry layer above.The microphysical and radiative properties of both clouds were characterized and modeled numerically. Calculations of droplet concentration and mean diameter profiles compare favorably with the measurements when entrainment effects are incorporated in the model.Radiative transfer calculations suggest radiation played an important role in driving convection in the more dynamically unstable of the two clouds. A simple model shows that radiative cooling causes sufficient negative buoyancy in cloudtop parcels to produce convective instability and to reproduce the observed downdraft velocities. Entrainment of warmer, drier air near cloudtop is shown to partially counteract the radiatively induced negative buoyancy in the downdrafts.

  17. Deep observation of A2163: studying a new bullet cluster

    NASA Astrophysics Data System (ADS)

    Bourdin, Herve

    2011-10-01

    Exhibiting a clear spatial separation between the gas and dark matter component of a fastly accreted subcluster, the `bullet cluster', 1E 0657-56, has provided us a unique laboratory to investigate the impact of violent cluster mergers on the Intra-Cluster Medium, galaxies and dark matter properties. In recent analyses of X-ray, optical and weak-lensing data, we show that the massive cluster A2163 also exhibits a crossing gas bullet separated from a galaxy and dark matter over-density, and suggest that both A2163 and 1E 0657-56 share a common merging scenario possibly just differing in the time elapsed after the closest cluster encounters. With this deeper XMM observation of A2163, we propose to refine our knowledge of the dynamics and geometry of the on-going subcluster accretion.

  18. Evaluating observational methods to quantify snow duration under diverse forest canopies

    NASA Astrophysics Data System (ADS)

    Dickerson-Lange, Susan E.; Lutz, James A.; Martin, Kael A.; Raleigh, Mark S.; Gersonde, Rolf; Lundquist, Jessica D.

    2015-02-01

    Forests cover almost 40% of the seasonally snow-covered regions in North America. However, operational snow networks are located primarily in forest clearings, and optical remote sensing cannot see through tree canopies to detect forest snowpack. Due to the complex influence of the forest on snowpack duration, ground observations in forests are essential. We therefore consider the effectiveness of different strategies to observe snow-covered area under forests. At our study location in the Pacific Northwest, we simultaneously deployed fiber-optic cable, stand-alone ground temperature sensors, and time-lapse digital cameras in three diverse forest treatments: control second-growth forest, thinned forest, and forest gaps (one tree height in diameter). We derived fractional snow-covered area and snow duration metrics from the colocated instruments to assess optimal spatial resolution and sampling configuration, and snow duration differences between forest treatments. The fiber-optic cable and the cameras indicated that mean snow duration was 8 days longer in the gap plots than in the control plots (p < 0.001). We conducted Monte Carlo experiments for observing mean snow duration in a 40 m forest plot, and found the 95% confidence interval was ±5 days for 10 m spacing between instruments and ±3 days for 6 m spacing. We further tested the representativeness of sampling one plot per treatment group by observing snow duration across replicated forest plots at the same elevation, and at a set of forest plots 250 m higher. Relative relationships between snow duration in the forest treatments are consistent between replicated plots, elevation, and two winters of data.

  19. Disciplinary Culture, Bibliometrics, and Historical Studies: Preliminary Observations.

    ERIC Educational Resources Information Center

    Buchanan, Anne L.; Herubel, Jean-Pierre V. M.

    1997-01-01

    Discusses bibliometrics and its relationship to historical studies in order to examine community formation of scientific and scholarly communication through institutional affiliation. A history journal is investigated and reveals an institutional and geographical mapping of the contributors. (Author/LRW)

  20. Study on short term prediction using observed water quality from 8-day intervals in Nakdong river

    NASA Astrophysics Data System (ADS)

    Kim, M.; Shon, T.; Joo, J.; Kim, J.; Shin, H.

    2012-12-01

    There are lots of accidents on water quality, like green algal blooms, occurring in Nakdong river which is one of the largest river in Korea. This is because of climate change around the world. It is essential to develop scientific and quantitative assessment methods. In this study, artificial neural network based on back propagation algorithm, which is simple and flexible method, was used for forecasting the water quality on the purpose of water resources management. Especially, as used observed water quality data from 8-day intervals in Nakdong river, it makes to increase the accuracy of water quality forecast over short term. This was established for predicting the water quality factors 1, 3, and 7 days ahead. The best model, as evaluated by its performance functions with RMSE and R2, was selected and applied to established models of BOD, DO, COD, and Chl-a using artificial neural network. The results showed that the models were suitable for 1 and 3 days forecasts in particular. This method is strong and convenient to predict water quality factors over the short term easily based on observed data. It is possible to overcome and manage problems related to the water resources. In the future, this will be a powerful method because it is basically based on observed water quality data.

  1. A New Method to Constrain Supernova Fractions Using X-ray Observations of Clusters of Galaxies

    NASA Technical Reports Server (NTRS)

    Bulbul, Esra; Smith, Randall K.; Loewenstein, Michael

    2012-01-01

    Supernova (SN) explosions enrich the intracluster medium (ICM) both by creating and dispersing metals. We introduce a method to measure the number of SNe and relative contribution of Type Ia supernovae (SNe Ia) and core-collapse supernovae (SNe cc) by directly fitting X-ray spectral observations. The method has been implemented as an XSPEC model called snapec. snapec utilizes a single-temperature thermal plasma code (apec) to model the spectral emission based on metal abundances calculated using the latest SN yields from SN Ia and SN cc explosion models. This approach provides a self-consistent single set of uncertainties on the total number of SN explosions and relative fraction of SN types in the ICM over the cluster lifetime by directly allowing these parameters to be determined by SN yields provided by simulations. We apply our approach to XMM-Newton European Photon Imaging Camera (EPIC), Reflection Grating Spectrometer (RGS), and 200 ks simulated Astro-H observations of a cooling flow cluster, A3112.We find that various sets of SN yields present in the literature produce an acceptable fit to the EPIC and RGS spectra of A3112. We infer that 30.3% plus or minus 5.4% to 37.1% plus or minus 7.1% of the total SN explosions are SNe Ia, and the total number of SN explosions required to create the observed metals is in the range of (1.06 plus or minus 0.34) x 10(exp 9), to (1.28 plus or minus 0.43) x 10(exp 9), fromsnapec fits to RGS spectra. These values may be compared to the enrichment expected based on well-established empirically measured SN rates per star formed. The proportions of SNe Ia and SNe cc inferred to have enriched the ICM in the inner 52 kiloparsecs of A3112 is consistent with these specific rates, if one applies a correction for the metals locked up in stars. At the same time, the inferred level of SN enrichment corresponds to a star-to-gas mass ratio that is several times greater than the 10% estimated globally for clusters in the A3112 mass range.

  2. A suggestion for quality assessment in systematic reviews of observational studies in nutritional epidemiology

    PubMed Central

    2016-01-01

    OBJECTIVES: It is important to control the quality level of the observational studies in conducting meta-analyses. The Newcastle-Ottawa Scale (NOS) is a representative tool used for this purpose. We investigated the relationship between high-quality (HQ) defined using NOS and the results of subgroup analysis according to study design. METHODS: We selected systematic review studies with meta-analysis which performed a quality evaluation on observational studies of diet and cancer by NOS. HQ determinations and the distribution of study designs were examined. Subgroup analyses according to quality level as defined by the NOS were also extracted. Equivalence was evaluated based on the summary effect size (sES) and 95% confidence intervals computed in the subgroup analysis. RESULTS: The meta-analysis results of the HQ and cohort groups were identical. The overall sES, which was obtained by combining the sES when equivalence was observed between the cohort and case-control groups, also showed equivalence. CONCLUSIONS: The results of this study suggest that it is more reasonable to control for quality level by performing subgroup analysis according to study design rather than by using HQ based on the NOS quality assessment tool. PMID:27156344

  3. Observing real-time social interaction via telecommunication methods in budgerigars (Melopsittacus undulatus).

    PubMed

    Ikkatai, Yuko; Okanoya, Kazuo; Seki, Yoshimasa

    2016-07-01

    Humans communicate with one another not only face-to-face but also via modern telecommunication methods such as television and video conferencing. We readily detect the difference between people actively communicating with us and people merely acting via a broadcasting system. We developed an animal model of this novel communication method seen in humans to determine whether animals also make this distinction. We built a system for two animals to interact via audio-visual equipment in real-time, to compare behavioral differences between two conditions, an "interactive two-way condition" and a "non-interactive (one-way) condition." We measured birds' responses to stimuli which appeared in these two conditions. We used budgerigars, which are small, gregarious birds, and found that the frequency of vocal interaction with other individuals did not differ between the two conditions. However, body synchrony between the two birds was observed more often in the interactive condition, suggesting budgerigars recognized the difference between these interactive and non-interactive conditions on some level. PMID:27040864

  4. Observing real-time social interaction via telecommunication methods in budgerigars (Melopsittacus undulatus).

    PubMed

    Ikkatai, Yuko; Okanoya, Kazuo; Seki, Yoshimasa

    2016-07-01

    Humans communicate with one another not only face-to-face but also via modern telecommunication methods such as television and video conferencing. We readily detect the difference between people actively communicating with us and people merely acting via a broadcasting system. We developed an animal model of this novel communication method seen in humans to determine whether animals also make this distinction. We built a system for two animals to interact via audio-visual equipment in real-time, to compare behavioral differences between two conditions, an "interactive two-way condition" and a "non-interactive (one-way) condition." We measured birds' responses to stimuli which appeared in these two conditions. We used budgerigars, which are small, gregarious birds, and found that the frequency of vocal interaction with other individuals did not differ between the two conditions. However, body synchrony between the two birds was observed more often in the interactive condition, suggesting budgerigars recognized the difference between these interactive and non-interactive conditions on some level.

  5. cAMP signaling microdomains and their observation by optical methods

    PubMed Central

    Calebiro, Davide; Maiellaro, Isabella

    2014-01-01

    The second messenger cyclic AMP (cAMP) is a major intracellular mediator of many hormones and neurotransmitters and regulates a myriad of cell functions, including synaptic plasticity in neurons. Whereas cAMP can freely diffuse in the cytosol, a growing body of evidence suggests the formation of cAMP gradients and microdomains near the sites of cAMP production, where cAMP signals remain apparently confined. The mechanisms responsible for the formation of such microdomains are subject of intensive investigation. The development of optical methods based on fluorescence resonance energy transfer (FRET), which allow a direct observation of cAMP signaling with high temporal and spatial resolution, is playing a fundamental role in elucidating the nature of such microdomains. Here, we will review the optical methods used for monitoring cAMP and protein kinase A (PKA) signaling in living cells, providing some examples of their application in neurons, and will discuss the major hypotheses on the formation of cAMP/PKA microdomains. PMID:25389388

  6. Image color reduction method for color-defective observers using a color palette composed of 20 particular colors

    NASA Astrophysics Data System (ADS)

    Sakamoto, Takashi

    2015-01-01

    This study describes a color enhancement method that uses a color palette especially designed for protan and deutan defects, commonly known as red-green color blindness. The proposed color reduction method is based on a simple color mapping. Complicated computation and image processing are not required by using the proposed method, and the method can replace protan and deutan confusion (p/d-confusion) colors with protan and deutan safe (p/d-safe) colors. Color palettes for protan and deutan defects proposed by previous studies are composed of few p/d-safe colors. Thus, the colors contained in these palettes are insufficient for replacing colors in photographs. Recently, Ito et al. proposed a p/dsafe color palette composed of 20 particular colors. The author demonstrated that their p/d-safe color palette could be applied to image color reduction in photographs as a means to replace p/d-confusion colors. This study describes the results of the proposed color reduction in photographs that include typical p/d-confusion colors, which can be replaced. After the reduction process is completed, color-defective observers can distinguish these confusion colors.

  7. Extending data worth methods to select multiple observations targeting specific hydrological predictions of interest

    NASA Astrophysics Data System (ADS)

    Vilhelmsen, Troels N.; Ferré, Ty P. A.

    2016-04-01

    Hydrological models are often developed to forecasting future behavior in response due to natural or human induced changes in stresses affecting hydrologic systems. Commonly, these models are conceptualized and calibrated based on existing data/information about the hydrological conditions. However, most hydrologic systems lack sufficient data to constrain models with adequate certainty to support robust decision making. Therefore, a key element of a hydrologic study is the selection of additional data to improve model performance. Given the nature of hydrologic investigations, it is not practical to select data sequentially, i.e. to choose the next observation, collect it, refine the model, and then repeat the process. Rather, for timing and financial reasons, measurement campaigns include multiple wells or sampling points. There is a growing body of literature aimed at defining the expected data worth based on existing models. However, these are almost all limited to identifying single additional observations. In this study, we present a methodology for simultaneously selecting multiple potential new observations based on their expected ability to reduce the uncertainty of the forecasts of interest. This methodology is based on linear estimates of the predictive uncertainty, and it can be used to determine the optimal combinations of measurements (location and number) established to reduce the uncertainty of multiple predictions. The outcome of the analysis is an estimate of the optimal sampling locations; the optimal number of samples; as well as a probability map showing the locations within the investigated area that are most likely to provide useful information about the forecasting of interest.

  8. Scalable Methods for Electronic Excitations and Optical Responses of Nanostructures: Mathematics to Algorithms to Observables

    SciTech Connect

    Carter, Emily A

    2013-02-02

    Kohn-Sham density functional theory (DFT) is a powerful, well-established tool for the study of condensed phase electronic structure. However, there are still a number of situations where its applicability is limited. The basic theme of our research is the development of first principles electronic structure approaches for condensed matter that goes beyond what can currently be done with standard implementations ofKohn-Sham DFT. Our efforts to this end have focused on two classes or' methods. The first addresses the well-lmown inability of DFT to handle strong, many-body electron correlation effects. Our approach is a DFT -based embedding theory, to treat localized features (e.g. impurity, adsorbate, vacancy, etc.) embedded in a periodic, metallic crystal. A description for the embedded region is provided by explicitly correlated, ab initio wave function methods. DFT, as a fo1n1ally ground state theory, does not give a good description of excited states; an additional feature of our approach is the ability to obtain excitations localized in this region. We apply our method to a first-principles study of the adsorption of a single magnetic Co ada tom on non-magnetic Cu( 111 ), a known Kondo system whose behavior is governed by strong electron correlation. The second class of methods that we are developing is an orbital-free density functional theory (OFDFT), which addresses the speed limitations ofKohn-Sham DFT. OFDFT is a powerful, O(N) scaling method for electronic structure calculations. Unlike Kohn-Sham DFT, OFDFT goes back to the original Hohenberg-Kohn idea of directly optimizing an energy functional which is an explicit functional of the density, without invoking an orbital description. This eliminates the need to manipulate orbitals, which leads to O(N{sup 3}) scaling in the Kahn-Sham approach. The speed of OFDFT allows direct electronic structure calculations on large systems on the order of thousands to tens of thousands of atoms, an expensive feat within

  9. The Reporting of Observational Clinical Functional Magnetic Resonance Imaging Studies: A Systematic Review

    PubMed Central

    Guo, Qing; Parlar, Melissa; Truong, Wanda; Hall, Geoffrey; Thabane, Lehana; McKinnon, Margaret; Goeree, Ron; Pullenayegum, Eleanor

    2014-01-01

    Introduction Complete reporting assists readers in confirming the methodological rigor and validity of findings and allows replication. The reporting quality of observational functional magnetic resonance imaging (fMRI) studies involving clinical participants is unclear. Objectives We sought to determine the quality of reporting in observational fMRI studies involving clinical participants. Methods We searched OVID MEDLINE for fMRI studies in six leading journals between January 2010 and December 2011.Three independent reviewers abstracted data from articles using an 83-item checklist adapted from the guidelines proposed by Poldrack et al. (Neuroimage 2008; 40: 409–14). We calculated the percentage of articles reporting each item of the checklist and the percentage of reported items per article. Results A random sample of 100 eligible articles was included in the study. Thirty-one items were reported by fewer than 50% of the articles and 13 items were reported by fewer than 20% of the articles. The median percentage of reported items per article was 51% (ranging from 30% to 78%). Although most articles reported statistical methods for within-subject modeling (92%) and for between-subject group modeling (97%), none of the articles reported observed effect sizes for any negative finding (0%). Few articles reported justifications for fixed-effect inferences used for group modeling (3%) and temporal autocorrelations used to account for within-subject variances and correlations (18%). Other under-reported areas included whether and how the task design was optimized for efficiency (22%) and distributions of inter-trial intervals (23%). Conclusions This study indicates that substantial improvement in the reporting of observational clinical fMRI studies is required. Poldrack et al.'s guidelines provide a means of improving overall reporting quality. Nonetheless, these guidelines are lengthy and may be at odds with strict word limits for publication; creation of a

  10. Morphologic and immunohistochemical observation of otosclerotic stapes: a preliminary study.

    PubMed

    Lim, D J; Robinson, M; Saunders, W H

    1987-01-01

    Stapes with otosclerotic lesions obtained during stapedectomies were examined with light microscopy, histochemistry, immunochemistry, and electron microscopy to elucidate the cellular mechanism(s) involved in this disease process. Three types of lesions were identified: cellular (spongiotic), fibrotic, and sclerotic. The cellular type is characterized by monocyte, macrophage, osteoblast, and osteoclast recruitment and their activation. Macrophage recruitment is an early event of otosclerosis. The fibrotic type is characterized by extensive fibrosis of the bone, and the sclerotic type is characterized by a paucity of bone cells. Cytochemical results showed a large accumulation of granular substances positive for periodic acid-Schiff stain along the edge of the marrow spaces coinciding with ultrastructural calcospherite deposits, suggesting that glycosaminoglycans are involved in the mineralization process. Acid phosphatase is largely localized in the osteoclasts, but a sporadic diffusion of this enzyme was observed in the demineralizing front of the preotosclerotic lesion. Immunoglobulin G and complement C3 were colocalized in pericapillary tissue, suggesting deposit of immune complex in the spongiotic lesion. This finding indicates a possibility that immune mechanisms are involved in otosclerosis. PMID:2829642

  11. Covariate Balance in Bayesian Propensity Score Approaches for Observational Studies

    ERIC Educational Resources Information Center

    Chen, Jianshen; Kaplan, David

    2015-01-01

    Bayesian alternatives to frequentist propensity score approaches have recently been proposed. However, few studies have investigated their covariate balancing properties. This article compares a recently developed two-step Bayesian propensity score approach to the frequentist approach with respect to covariate balance. The effects of different…

  12. Staff Reactions to Challenging Behaviour: An Observation Study

    ERIC Educational Resources Information Center

    Lambrechts, Greet; Van Den Noortgate, Wim; Eeman, Lieve; Maes, Bea

    2010-01-01

    Staff reactions play an important role in the development and maintaining of clients' challenging behaviour. Because there is a paucity of research on staff reactions in naturalistic settings, this study examined sequential associations between challenging behaviour and staff reactions by means of a descriptive analysis. We analysed video…

  13. Experimental and Observational Data in the Study of Interlanguage Pragmatics.

    ERIC Educational Resources Information Center

    Hartford, Beverly S.; Bardovi-Harlig, Kathleen

    1992-01-01

    A study compared (1) data on rejections of advice by native and non-native speakers collected from natural conversation with (2) data collected from a discourse completion task (DCT). Subjects were students in an academic advising session (13 native speakers, 11 non-native speakers of English) who responded to a DCT and students (18 native…

  14. Interpersonal Conflict in Preschoolers: A Naturalistic Observation Study.

    ERIC Educational Resources Information Center

    Shantz, David W.; Schomer, Joyce

    This study of the behavior of a mixed group of male and female preschoolers in an indoor, free-play setting was designed to clarify two general issues: (1) the ratio of aggressive to non-aggressive disputes and the factors in the situation which may be associated with this relationship; and (2) the factors in the conflict episodes themselves which…

  15. Musical Expression: An Observational Study of Instrumental Teaching

    ERIC Educational Resources Information Center

    Karlsson, Jessika; Juslin, Patrik N.

    2008-01-01

    Research has shown that both music students and teachers think that expression is important. Yet, we know little about how expression is taught to students. Such knowledge is needed in order to enhance teaching of expression. The aim of this study was thus to explore the nature of instrumental music teaching in its natural context, with a focus on…

  16. Writing Instruction in First Grade: An Observational Study

    ERIC Educational Resources Information Center

    Coker, David L., Jr.; Farley-Ripple, Elizabeth; Jackson, Allison F.; Wen, Huijing; MacArthur, Charles A.; Jennings, Austin S.

    2016-01-01

    As schools work to meet the ambitious Common Core State Standards in writing in the US, instructional approaches are likely to be examined (National Governors Association Center for Best Practices, Council of Chief State School Officers, 2010). However, there is little research on the current state of instruction. This study was designed to…

  17. Predicting Three Dimensions of Residential Curbside Recycling: An Observational Study.

    ERIC Educational Resources Information Center

    Oskamp, Stuart; Burkhardt, Rachel L.; Schultz, P. Wesley; Hurin, Sharrilyn; Zelezny, Lynnette

    1998-01-01

    Three dependent variables of household recycling behavior were studied in a suburban community over eight weeks, 10 independent variables serving as predictors. Results indicate that many of the independent variables that predicted recycling behavior in past research have weaker relationships in current, more convenient curbside programs.…

  18. ORD BEST PRACTICES FOR OBSERVATIONAL HUMAN EXPOSURE MEASUREMENT STUDIES

    EPA Science Inventory

    This abstract describes a presentation for the 2007 Society of Toxicology Annual Meeting in Charlotte, NC on March 27, 2007. It will be included in a special Issues Session titled "Scientific and Ethical Considerations in Human Exposure Studies." The presentation desc...

  19. Observational Study on Initiation and Acceleration of Coronal Mass Ejections

    NASA Technical Reports Server (NTRS)

    Zhang, Jie

    2005-01-01

    During the performance period, we have successfully carried out all the tasks and fulfilled all the scientific objectives outlined in the proposal, which are about building a C1 Ch4E catalog and studying CME accelerations in both inner and outer corona.

  20. An Observational Study of Co-Rumination in Adolescent Friendships

    ERIC Educational Resources Information Center

    Rose, Amanda J.; Schwartz-Mette, Rebecca A.; Glick, Gary C.; Smith, Rhiannon L.; Luebbe, Aaron M.

    2014-01-01

    Co-rumination is a dyadic process between relationship partners that refers to excessively discussing problems, rehashing problems, speculating about problems, mutual encouragement of problem talk, and dwelling on negative affect. Although studies have addressed youths' "tendency" to co-ruminate, little is known about the nature of…

  1. Methods for environmental change; an exploratory study

    PubMed Central

    2012-01-01

    Background While the interest of health promotion researchers in change methods directed at the target population has a long tradition, interest in change methods directed at the environment is still developing. In this survey, the focus is on methods for environmental change; especially about how these are composed of methods for individual change (‘Bundling’) and how within one environmental level, organizations, methods differ when directed at the management (‘At’) or applied by the management (‘From’). Methods The first part of this online survey dealt with examining the ‘bundling’ of individual level methods to methods at the environmental level. The question asked was to what extent the use of an environmental level method would involve the use of certain individual level methods. In the second part of the survey the question was whether there are differences between applying methods directed ‘at’ an organization (for instance, by a health promoter) versus ‘from’ within an organization itself. All of the 20 respondents are experts in the field of health promotion. Results Methods at the individual level are frequently bundled together as part of a method at a higher ecological level. A number of individual level methods are popular as part of most of the environmental level methods, while others are not chosen very often. Interventions directed at environmental agents often have a strong focus on the motivational part of behavior change. There are different approaches targeting a level or being targeted from a level. The health promoter will use combinations of motivation and facilitation. The manager will use individual level change methods focusing on self-efficacy and skills. Respondents think that any method may be used under the right circumstances, although few endorsed coercive methods. Conclusions Taxonomies of theoretical change methods for environmental change should include combinations of individual level methods that may

  2. Presentation of continuous outcomes in randomised trials: an observational study

    PubMed Central

    Savage, Dan F; Altman, Douglas G

    2012-01-01

    Objective To characterise the percentage of available outcome data being presented in reports of randomised clinical trials with continuous outcome measures, thereby determining the potential for incomplete reporting bias. Design Descriptive cross sectional study. Data sources A random sample of 200 randomised trials from issues of 20 medical journals in a variety of specialties during 2007–09. Main outcome measures For each paper’s best reported primary outcome, we calculated the fraction of data reported using explicit scoring rules. For example, a two arm trial with 100 patients per limb that reported 2 sample sizes, 2 means, and 2 standard deviations reported 6/200 data elements (1.5%), but if that paper included a scatterplot with 200 points it would score 200/200 (100%). We also assessed compliance with 2001 CONSORT items about the reporting of results. Results The median percentage of data reported for the best reported continuous outcome was 9% (interquartile range 3–26%) but only 3.5% (3–7%) when we adjusted studies to 100 patients per arm to control for varying study size; 17% of articles showed 100% of the data. Tables were the predominant means of presenting the most data (59% of articles), but papers that used figures reported a higher proportion of data. There was substantial heterogeneity among journals with respect to our primary outcome and CONSORT compliance. Limitations We studied continuous outcomes of randomised trials in higher impact journals. Results may not apply to categorical outcomes, other study designs, or other journals. Conclusions Trialists present only a small fraction of available data. This paucity of data may increase the potential for incomplete reporting bias, a failure to present all relevant information about a study’s findings. PMID:23249670

  3. Direct observation of molybdenum disulfide, MoS2, domains by using a liquid crystalline texture method.

    PubMed

    Kim, Dae Woo; Ok, Jong Min; Jung, Woo-Bin; Kim, Jong-Seon; Kim, Seon Joon; Choi, Hyung Ouk; Kim, Yun Ho; Jung, Hee-Tae

    2015-01-14

    Because the properties of molybdenum disulfide (MoS2) are strongly influenced by the sizes and boundaries of its domains, the direct visualization of large-area MoS2 domains is one of the most important challenges in MoS2 research. In the current study, we developed a simple and rapid method to observe and determine the boundaries of MoS2 domains. The technique, which depends on observations of nematic liquid crystal textures on the MoS2 surface, does not damage the sample and is not limited by domain size. Thus, this approach should significantly aid not only efforts aimed at gaining an understanding of the relationships between grain boundaries and properties of MoS2 but also those focusing on how domain sizes are controlled during large-area synthesis.

  4. Atmospheric Tides over the Pyrenees. Observational study and numerical simulation

    NASA Astrophysics Data System (ADS)

    Diaz de Argandoña, Javier; Ezcurra, Agustin; Saenz, Jon; Campistron, Bernard; Ibarra-Berastegi, Gabriel; Saïd, Frederique

    2010-05-01

    Atmospheric tides refer to the oscillations in the atmosphere whose periods are integral fractions of a day. In some magnitudes (e.g. temperature), these oscillations are quite evident but in others, such as the pressure in the midlatitudes, they are usually masked by the greater variations produced during the transient pass of synoptic weather systems. The main forcing agent for these oscillations, as opposed to ocean tides, is not the solar or lunar gravity pull, but the daily variations in solar insolation and the thermal effect derived from it. The main components of the solar atmospheric tides are the semidiurnal, with a 12-hour period, and the 24-hour period component or diurnal tide. The global scale tides are usually referred to as migrating tides, and are the result of a gravity wave which travels westerly with the apparent motion of the sun. Nevertheless, a significant part of the tide can be related to local characteristics, and this part is considered as the non-migrating component of the tide. Barometric tides around the Pyrenees mountain range are analyzed by means of ground synoptic stations data recorded during one year, ground data from PYREX experiment and the CRA/LA VHF wind profiler installed in the North of the range. Tides are decomposed in their diurnal and semidiurnal components. Diurnal tides show a strong non migrating component and are very dependent on local conditions. Semidiurnal tides are more homogeneous and present a north-south asymmetry, also noted in the Alps. This cross-range asymmetry seems to be related to some interference effect caused by the mountain range in the migrating semidiurnal tide wave. The diurnal component asymmetry presents a very strong seasonal variation, so its cause must be probably related to thermal local conditions. A three month simulation carried out with NCAR's WRF limited area model reproduces this asymmetry and some of the features of the observed tides.

  5. Study of the low latitude ionospheric turbulence observed by DEMETER

    NASA Astrophysics Data System (ADS)

    Li, F.; Lefeuvre, F.; Parrot, M.

    Following previous works from Molchanov et al 2002a 2002b 2004a 2004b and Hobara et al 2005 data bases dedicated to the systematic analysis of the power and spectral indices of the electric field have been elaborated Two data bases are considered one for the survey mode and the other for the burst mode For the survey mode estimations of the turbulence parameters are performed from the 8 first Fourier components of the averaged power spectra 0-150 Hz frequency band A single slope power law model f - alpha is assumed A quality factor allows to test that hypothesis For the burst mode the power spectra are derived from the waveforms One and two slope models are systematically tested Results are presented and the possibility to use these data bases for correlation with seismic activity is discussed Y Hobara F Lefeuvre M Parrot and O A Molchanov Low-latitude ionospheric turbulence observed by Aureol-3 satellite Annales Geophysicae 23 1259--1270 2005 Molchanov O A Hayakawa M Afonin V V Akentieva O A and Mareev E A Possible influence of seismicity by gravity waves on ionospheric equatorial anomaly from data of IK-24 satellite 1 Search for idea of seismo-ionosphere coupling Seismo Electromagnetics Lithosphere-Atmosphere-Ionosphere Coupling edited by Hayakawa M and Molchanov O A TERRAPUB Tokyo 275--285 2002a Molchanov O A Hayakawa M Afonin V V Akentieva O A Mareev E A and Trakhtengerts V Yu Possible influence of seismicity by gravity waves on ionospheric

  6. Bedside practice of blood transfusion in a large teaching hospital in Uganda: An observational study

    PubMed Central

    de Graaf, J. D.; Kajja, I.; Bimenya, G. S.; Postma, M. J.; Sibinga, C. Th.

    2009-01-01

    Background: Adverse transfusion reactions can cause morbidity and death to patients who receive a blood transfusion. Blood transfusion practice in Mulago Hospital, Kampala, Uganda is analyzed to see if and when these practices play a role in the morbidity and mortality of patients. Materials and Methods: An observational study on three wards of Mulago Hospital. Physicians, paramedics, nurses, medical students and nurse students were observed using two questionnaires. For comparison, a limited observational study was performed in the University Medical Centre Groningen (UMCG) in Groningen, The Netherlands. Results: In Mulago Hospital guidelines for blood transfusion practice were not easily available. Medical staff members work on individual professional levels. Students perform poorly due to inconsistency in their supervision. Documentation of blood transfusion in patient files is scarce. There is no immediate bedside observation, so transfusion reactions and obstructions in the blood transfusion flow are not observed. Conclusion: The poor blood transfusion practice is likely to play a role in the morbidity and mortality of patients who receive a blood transfusion. There is a need for a blood transfusion policy and current practical guidelines. PMID:20808647

  7. Observing power blackouts from space - A disaster related study

    NASA Astrophysics Data System (ADS)

    Aubrecht, C.; Elvidge, C. D.; Ziskin, D.; Baugh, K. E.; Tuttle, B.; Erwin, E.; Kerle, N.

    2009-04-01

    In case of emergency disaster managers worldwide require immediate information on affected areas and estimations of the number of affected people. Natural disasters such as earthquakes, hurricanes, tornados, wind and ice storms often involve failures in the electrical power generation system and grid. Near real time identification of power blackouts gives a first impression of the area affected by the event (Elvidge et al. 2007), which can subsequently be linked to population estimations. Power blackouts disrupt societal activities and compound the difficulties associated with search and rescue, clean up, and the provision of food and other supplies following a disastrous event. Locations and spatial extents of power blackouts are key considerations in planning and execution of the primary disaster missions of emergency management organizations. To date only one satellite data source has been used successfully for the detection of power blackouts. Operated by NOAA's National Geophysical Data Center (NGDC) the U.S. Air Force Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) offers a unique capability to observe lights present at the Earth's surface at night. Including a pair of visible and thermal spectral bands and originally designed to detect moonlit clouds, this sensor enables mapping of lights from cities and towns, gas flares and offshore platforms, fires, and heavily lit fishing boats. The low light imaging of the OLS is accomplished using a photomultiplier tube (PMT) which intensifies the visible band signal at night. With 14 orbits collected per day and a 3.000 km swath width, each OLS is capable of collecting a complete set of images of the Earth every 24 hours. NGDC runs the long-term archive for OLS data with the digital version extending back to 1992. OLS data is received by NGDC in near real time (1-2 hours from acquisition) and subscription based services for the near real time data are provided for users all over the

  8. Physical and dynamical studies of meteors. [radar observation of fragmentation

    NASA Technical Reports Server (NTRS)

    Southworth, R. B.; Sekanina, Z.

    1974-01-01

    Distribution of meteors in streams detected in the synoptic-year meteor sample plus a study of the fragmentation characteristics of the synoptic-year meteor sample are presented. Population coefficients and dispersion coefficients were determined for each meteor stream. These two parameters serve to determine the number of definite members of the stream in the sample used, and to estimate the actual space density of meteor streams. From results of the fragmentation study, it appears that the main body of most radar meteors does not ablate fragments layer by layer, but collapses rather suddenly under dynamic pressures on the order of 0,0002 dynes/cm. Furthermore, it is believed that fragmentation does not cause a serious selection effect in the radar meteor data.

  9. Modified Conditional Merging technique: a new method to estimate a rainfall field combining remote sensed data and raingauge observations

    NASA Astrophysics Data System (ADS)

    Pignone, Flavio; Rebora, Nicola; Silvestro, Francesco

    2015-04-01

    The estimation of the rainfall field, especially its spatial distribution and position, is a crucial task both for rainfall nowcasting and for modeling catchment response to rainfall. Some studies of literature about multisensor datafusion prove that combining data from different sensors (especially raingauges and radar) represents the best way to obtain an enhanced ad more reliable estimation of QPE and of the associated river discharge. Sinclair and Peagram (2004) have proposed the Conditional Merging (CM) technique, a merging algorithm which extract the information content from the observed data and use it within an interpolation method to obtain the rainfall maps. The raingauges provide a punctual measure of the observed "real" rainfall while the remote sensors (radar network or satellite constellation) supply rainfall estimation maps which give an idea of the spatial correlation structure of the observed field. In this work is studied an enhanced algorithm based on CM, called Modified Conditional Merging, which can be used in real-time to produce the optimal rainfall maps. The area of interest, where the CM has been applied, is Italy, where are both available a dense network of raingauge measurements (about 3000 stations) and a QPE estimated by the Italian Radar composite. The main innovation respect to classical CM is to estimate the structure of covariance and the length of spatial correlation λ, for every raingauge, directly from the cumulated radar rainfall fields. The advantages of this method is to estimate the local characteristic of the domain to obtain information at smaller scale, very useful for convective events. A cross-validation of the new method was done and several statistical scores were applied on the results. The validation on a large number of Italian past event along with its operational use are presented and discussed.

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

    ERIC Educational Resources Information Center

    Anliak, Sakire; Sahin, Derya

    2010-01-01

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

  11. Evaluating Observational Methods to Quantify Snow Duration under Diverse Forest Canopies

    NASA Astrophysics Data System (ADS)

    Dickerson-Lange, S. E.; Lutz, J. A.; Martin, K.; Raleigh, M. S.; Gersonde, R.; Lundquist, J. D.

    2014-12-01

    Forests cover over 40% of the seasonally snow-covered regions in North America. However, operational snow networks are located primarily in forest clearings, and optical remote sensing cannot see through tree canopies to detect forest snowpack. Due to the complex influence of the forest on snowpack duration, ground observations in forests are essential. We therefore consider the effectiveness of different strategies to observe snow covered area under forests. At our study location in the Pacific Northwest, we simultaneously deployed fiber-optic cable, stand-alone ground temperature sensors, and time-lapse digital cameras in three different forest treatments: control second-growth forest, thinned forest, and forest gaps (one tree height in diameter). We derived fractional snow covered area and snow duration metrics from the co-located instruments to assess optimal spatial resolution and sampling configuration. The fiber-optic cable and the camera detected a significant difference of 8 days in mean snow duration between the gap and control plots. Monte Carlo experiments based on our results suggest that 10 m spacing of self-recording ground temperature sensors across a 40 m forest plot will capture mean snow duration to ± 5 days whereas 6 m spacing reduces the 95% confidence interval to ± 3 days. We further tested the representativeness of sampling one plot per treatment group by observing snow duration across replicated forest plots at the same elevation, and at a set of forest plots 250 m higher. Relative relationships between snow duration in the forest treatments are consistent between replicated plots, elevation, and two winters of data.

  12. Cost-of-illness studies : a review of current methods.

    PubMed

    Akobundu, Ebere; Ju, Jing; Blatt, Lisa; Mullins, C Daniel

    2006-01-01

    The number of cost-of-illness (COI) studies has expanded considerably over time. One outcome of this growth is that the reported COI estimates are inconsistent across studies, thereby raising concerns over the validity of the estimates and methods. Several factors have been identified in the literature as reasons for the observed variation in COI estimates. To date, the variation in the methods used to calculate costs has not been examined in great detail even though the variations in methods are a major driver of variation in COI estimates. The objective of this review was to document the variation in the methodologies employed in COI studies and to highlight the benefits and limitations of these methods. The review of COI studies was implemented following a four-step procedure: (i) a structured literature search of MEDLINE, JSTOR and EconLit; (ii) a review of abstracts using pre-defined inclusion and exclusion criteria; (iii) a full-text review using pre-defined inclusion and exclusion criteria; and (iv) classification of articles according to the methods used to calculate costs. This review identified four COI estimation methods (Sum_All Medical, Sum_Diagnosis Specific, Matched Control and Regression) that were used in categorising articles. Also, six components of direct medical costs and five components of indirect/non-medical costs were identified and used in categorising articles.365 full-length articles were reflected in the current review following the structured literature search. The top five cost components were emergency room/inpatient hospital costs, outpatient physician costs, drug costs, productivity losses and laboratory costs. The dominant method, Sum_Diagnosis Specific, was a total costing approach that restricted the summation of medical expenditures to those related to a diagnosis of the disease of interest. There was considerable variation in the methods used within disease subcategories. In several disease subcategories (e.g. asthma, dementia

  13. Cost-of-illness studies : a review of current methods.

    PubMed

    Akobundu, Ebere; Ju, Jing; Blatt, Lisa; Mullins, C Daniel

    2006-01-01

    The number of cost-of-illness (COI) studies has expanded considerably over time. One outcome of this growth is that the reported COI estimates are inconsistent across studies, thereby raising concerns over the validity of the estimates and methods. Several factors have been identified in the literature as reasons for the observed variation in COI estimates. To date, the variation in the methods used to calculate costs has not been examined in great detail even though the variations in methods are a major driver of variation in COI estimates. The objective of this review was to document the variation in the methodologies employed in COI studies and to highlight the benefits and limitations of these methods. The review of COI studies was implemented following a four-step procedure: (i) a structured literature search of MEDLINE, JSTOR and EconLit; (ii) a review of abstracts using pre-defined inclusion and exclusion criteria; (iii) a full-text review using pre-defined inclusion and exclusion criteria; and (iv) classification of articles according to the methods used to calculate costs. This review identified four COI estimation methods (Sum_All Medical, Sum_Diagnosis Specific, Matched Control and Regression) that were used in categorising articles. Also, six components of direct medical costs and five components of indirect/non-medical costs were identified and used in categorising articles.365 full-length articles were reflected in the current review following the structured literature search. The top five cost components were emergency room/inpatient hospital costs, outpatient physician costs, drug costs, productivity losses and laboratory costs. The dominant method, Sum_Diagnosis Specific, was a total costing approach that restricted the summation of medical expenditures to those related to a diagnosis of the disease of interest. There was considerable variation in the methods used within disease subcategories. In several disease subcategories (e.g. asthma, dementia

  14. Thermoacoustic CT of the breast: pilot study observations

    NASA Astrophysics Data System (ADS)

    Kruger, Robert A.; Kiser, William L., Jr.; Romilly, A. P.; Scmidt, Phyllis

    2001-06-01

    In order to assess the potential clinical utility of using thermoacoustic computer tomography (TCT) to image the breast, we conducted a retrospective pilot study of 78 patients. We recruited patients in three age groups (<40,40-50,>50 years). The study population was further segregated into normal and suspicious based on the results of the previous x-ray mammography and ultrasound. Image quality was evaluated qualitatively by consensus of two trained mammographers using a 4-point scale. The appearance of normal anatomy, cysts, benign disease and cancer was noted. Patients were also asked to rate the comfort of the TCT exam and to indicate a personal preference for x-ray mammography or TCT. Analysis of the data indicated that TCT image quality was dependent upon both patient age and breast density, improving with both increasing breast density and decreasing patient age. Fibrocystic disease was well seen, cysts appearing as areas of low RF absorption. Fibroadenomas did not demonstrate contrast enhancement with the exception of one patient with associated atypical hyperplasia. Cancer displayed higher RF absorption than surrounding tissues in 4/7 patients in whom cancer was confirmed, including one patient with a 7-mm ductal carcinoma in situ (DCIS).

  15. An observational and theoretical study of Colorado lee cyclogenesis

    NASA Technical Reports Server (NTRS)

    Clark, John H. E.

    1990-01-01

    A cyclogenesis event that occurred over Colorado in early March of 1981 is the focus of this study. Two features that seemed to play a role in storm initiation were a traveling upper troposphere disturbance associated with an undulation on the subtropical front and a warm-cored shallow surface trough that was guided along the eastern slope of the Rockies from Canada to Colorado. The arrival of the latter feature initiated a sudden shift of the surface flow from upslope to downslope on the eastern side of the continental divide. A time-dependent quasi-geostrophic model was used to study the interaction of the traveling short wave and a broad topographic surface ridge in the presence of a baroclinic mainly westerly background flow. Westerly and easterly background surface winds were used to determine whether the surface trough arrival had any influence on the vigor of lee cyclogenesis initiated by the upper troposphere short-wave trough. With surface westerlies rapid cyclogenesis occurred, while with surface easterlies little cyclogenesis was found to the east of the Rockies. Thus, the shallow surface trough's arrival seemed to be crucial to storm initiation. These findings were based on a linear model. It is shown, however, that the height of the Rockies necessitates the inclusion of finite amplitude effects associated with the lower boundary into the model.

  16. Offshore observations of eastern red bats (Lasiurus borealis) in the Mid-Atlantic United States using multiple survey methods.

    PubMed

    Hatch, Shaylyn K; Connelly, Emily E; Divoll, Timothy J; Stenhouse, Iain J; Williams, Kathryn A

    2013-01-01

    Little is known about the migration and movements of migratory tree-roosting bat species in North America, though anecdotal observations of migrating bats over the Atlantic Ocean have been reported since at least the 1890s. Aerial surveys and boat-based surveys of wildlife off the Atlantic Seaboard detected a possible diurnal migration event of eastern red bats (Lasiurus borealis) in September 2012. One bat was sighted approximately 44 km east of Rehoboth Beach, Delaware during a boat-based survey. Eleven additional bats were observed between 16.9 and 41.8 km east of New Jersey, Delaware, and Virginia in high definition video footage collected during digital aerial surveys. Observations were collected incidentally as part of a large baseline study of seabird, marine mammal, and sea turtle distributions and movements in the offshore environment. Digital survey methods also allowed for altitude estimation for several of these bats at >100 m above sea level. These observations provide new evidence of bat movements offshore, and offer insight into their flight heights above sea level and the times of day at which such migrations may occur.

  17. Offshore Observations of Eastern Red Bats (Lasiurus borealis) in the Mid-Atlantic United States Using Multiple Survey Methods

    PubMed Central

    Hatch, Shaylyn K.; Connelly, Emily E.; Divoll, Timothy J.; Stenhouse, Iain J.; Williams, Kathryn A.

    2013-01-01

    Little is known about the migration and movements of migratory tree-roosting bat species in North America, though anecdotal observations of migrating bats over the Atlantic Ocean have been reported since at least the 1890s. Aerial surveys and boat-based surveys of wildlife off the Atlantic Seaboard detected a possible diurnal migration event of eastern red bats (Lasiurus borealis) in September 2012. One bat was sighted approximately 44 km east of Rehoboth Beach, Delaware during a boat-based survey. Eleven additional bats were observed between 16.9 and 41.8 km east of New Jersey, Delaware, and Virginia in high definition video footage collected during digital aerial surveys. Observations were collected incidentally as part of a large baseline study of seabird, marine mammal, and sea turtle distributions and movements in the offshore environment. Digital survey methods also allowed for altitude estimation for several of these bats at >100 m above sea level. These observations provide new evidence of bat movements offshore, and offer insight into their flight heights above sea level and the times of day at which such migrations may occur. PMID:24367614

  18. Enhancement of the accuracy of the ( P-ω) method through the implementation of a nonlinear robust observer

    NASA Astrophysics Data System (ADS)

    Kfoury, G. A.; Chalhoub, N. G.; Henein, N. A.; Bryzik, W.

    2006-04-01

    The ( P-ω) method is a model-based approach developed for determining the instantaneous friction torque in internal combustion engines. This scheme requires measurements of the cylinder gas pressure, the engine load torque, the crankshaft angular displacement and its time derivatives. The effects of the higher order dynamics of the crank-slider mechanism on the measured angular motion of the crankshaft have caused the ( P-ω) method to yield erroneous results, especially, at high engine speeds. To alleviate this problem, a nonlinear sliding mode observer has been developed herein to accurately estimate the rigid and flexible motions of the piston-assembly/connecting-rod/crankshaft mechanism of a single cylinder engine. The observer has been designed to yield a robust performance in the presence of disturbances and modeling imprecision. The digital simulation results, generated under transient conditions representing a decrease in the engine speed, have illustrated the rapid convergence of the estimated state variables to the actual ones in the presence of both structured and unstructured uncertainties. Moreover, this study has proven that the use of the estimated rather than the measured angular displacement of the crankshaft and its time derivatives can significantly improve the accuracy of the ( P-ω) method in determining the instantaneous engine friction torque.

  19. Observing the ocean with different platforms/methods. Advantages, disadvantages and lessons learnt

    NASA Astrophysics Data System (ADS)

    Petihakis, George; Potiris, Manolis; Ntoumas, Manolis; Frangoulis, Kostas; Tsiaras, Kostas; Triantafyllou, George; Pollani, Annika

    2015-04-01

    Methods for observing/measuring the ocean, present remarkable diversity. In situ sampling or remote sensing, automated or not measurements with sensing probes, utilize different measuring principles, sample different parts of the system, are characterized by different accuracy/precision and sample over a large range of spatial and temporal scales with variable resolution. Measurements, quite often are dependent on the platform design and the platform interaction with the highly variable ambient environment. To add to the aforementioned issues that render the combination of data from different sources challenging from a scientific perspective, there are also a number of technical and data issues. These are important for the good operational status of the platforms, the smooth data flow and the collection of appropriate meta-data. Finally the raw data files need to be processed into a user friendly output format so the operator will be able to identify as early as possible sensor drift and failures. In this work, data from different observation platforms/sensors is analysed and compared, while mechanisms and processes responsible for differences are identified. More detailed, temperature, salinity and chlorophyll data from four fixed observing stations, one Ferry Box, satellites and a monthly in situ sampling program, is used. Main results indicate that a) regular calibration according to expected parameter range and well-defined, consistent deployment plan of proven sensors is sufficient for acquiring high quality data in the long term. Better knowledge of site specific response of new instrumentation is required for producing consistent long term data b) duplicate sensors on one platform considerably improve data flow and data quality c) if an area is sampled by multiple platforms, then platform dependent errors can be quantified d) fixed point observatories are efficient tools for assessing regional performance of satellite products. Higher vertical and temporal

  20. On methods for studying stochastic disease dynamics.

    PubMed

    Keeling, M J; Ross, J V

    2008-02-01

    Models that deal with the individual level of populations have shown the importance of stochasticity in ecology, epidemiology and evolution. An increasingly common approach to studying these models is through stochastic (event-driven) simulation. One striking disadvantage of this approach is the need for a large number of replicates to determine the range of expected behaviour. Here, for a class of stochastic models called Markov processes, we present results that overcome this difficulty and provide valuable insights, but which have been largely ignored by applied researchers. For these models, the so-called Kolmogorov forward equation (also called the ensemble or master equation) allows one to simultaneously consider the probability of each possible state occurring. Irrespective of the complexities and nonlinearities of population dynamics, this equation is linear and has a natural matrix formulation that provides many analytical insights into the behaviour of stochastic populations and allows rapid evaluation of process dynamics. Here, using epidemiological models as a template, these ensemble equations are explored and results are compared with traditional stochastic simulations. In addition, we describe further advantages of the matrix formulation of dynamics, providing simple exact methods for evaluating expected eradication (extinction) times of diseases, for comparing expected total costs of possible control programmes and for estimation of disease parameters. PMID:17638650

  1. An observational Study of the "Interstate 5" Dust Storm Case.

    NASA Astrophysics Data System (ADS)

    Pauley, Patricia M.; Baker, Nancy L.; Barker, Edward H.

    1996-04-01

    over the San Joaquin Valley during daytime hours on the day of the collisions, boundary layer mixing associated with solar heating of the earth's surface was then able to generate high surface winds. Once the high surface winds began, a dust storm was inevitable, since winter rains had not yet seed and soil conditions were drier than usual in this sixth consecutive drought year. Surface observations from a variety of sources depict blowing dust and high surface winds at numerous locations in the San Joaguin Valley, the Mojave and other desert sites, and in the Los Angeles Basin and other south coast sites. High surface winds and low visibilities began in the late morning at desert and valley sites and lasted until just after sunset, consistent with the hypothesized heating-induced mixing. The 0000 UTC soundings in California portrayed an adiabatic layer from the surface to at least 750 hPa, also supporting the existence of mixing. On the other hand, the high winds in the Los Angeles Basin began near sunset in the wake of a propagating mesoscale trough that appeared to have formed in the lee of the mountains that separate the Los Angeles Basin from the San Joaquin Valley.

  2. Defining safe criteria to diagnose miscarriage: prospective observational multicentre study

    PubMed Central

    Preisler, Jessica; Kopeika, Julia; Ismail, Laure; Vathanan, Veluppillai; Farren, Jessica; Abdallah, Yazan; Battacharjee, Parijat; Van Holsbeke, Caroline; Bottomley, Cecilia; Gould, Deborah; Johnson, Susanne; Stalder, Catriona; Van Calster, Ben; Hamilton, Judith; Timmerman, Dirk

    2015-01-01

    Objectives To validate recent guidance changes by establishing the performance of cut-off values for embryo crown-rump length and mean gestational sac diameter to diagnose miscarriage with high levels of certainty. Secondary aims were to examine the influence of gestational age on interpretation of mean gestational sac diameter and crown-rump length values, determine the optimal intervals between scans and findings on repeat scans that definitively diagnose pregnancy failure.) Design Prospective multicentre observational trial. Setting Seven hospital based early pregnancy assessment units in the United Kingdom. Participants 2845 women with intrauterine pregnancies of unknown viability included if transvaginal ultrasonography showed an intrauterine pregnancy of uncertain viability. In three hospitals this was initially defined as an empty gestational sac <20 mm mean diameter with or without a visible yolk sac but no embryo, or an embryo with crown-rump length <6 mm with no heartbeat. Following amended guidance in December 2011 this definition changed to a gestational sac size <25 mm or embryo crown-rump length <7 mm. At one unit the definition was extended throughout to include a mean gestational sac diameter <30 mm or embryo crown-rump length <8 mm. Main outcome measures Mean gestational sac diameter, crown-rump length, and presence or absence of embryo heart activity at initial and repeat transvaginal ultrasonography around 7-14 days later. The final outcome was pregnancy viability at 11-14 weeks’ gestation. Results The following indicated a miscarriage at initial scan: mean gestational sac diameter ≥25 mm with an empty sac (364/364 specificity: 100%, 95% confidence interval 99.0% to 100%), embryo with crown-rump length ≥7 mm without visible embryo heart activity (110/110 specificity: 100%, 96.7% to 100%), mean gestational sac diameter ≥18 mm for gestational sacs without an embryo presenting after 70 days’ gestation (907/907 specificity: 100%, 99.6% to

  3. Body Characteristics, Dietary Protein and Body Weight Regulation. Reconciling Conflicting Results from Intervention and Observational Studies?

    PubMed Central

    Ankarfeldt, Mikkel Z.; Ängquist, Lars; Stocks, Tanja; Jakobsen, Marianne U.; Overvad, Kim; Halkjær, Jytte; Saris, Wim H. M.; Astrup, Arne; Sørensen, Thorkild I. A.

    2014-01-01

    Background/Objectives Physiological evidence indicates that high-protein diets reduce caloric intake and increase thermogenic response, which may prevent weight gain and regain after weight loss. Clinical trials have shown such effects, whereas observational cohort studies suggest an association between greater protein intake and weight gain. In both types of studies the results are based on average weight changes, and show considerable diversity in both directions. This study investigates whether the discrepancy in the evidence could be due to recruitment of overweight and obese individuals into clinical trials. Subjects/Methods Data were available from the European Diet, Obesity and Genes (DiOGenes) post-weight-loss weight-maintenance trial and the Danish Diet, Cancer and Health (DCH) cohort. Participants of the DCH cohort were matched with participants from the DiOGenes trial on gender, diet, and body characteristics. Different subsets of the DCH-participants, comparable with the trial participants, were analyzed for weight maintenance according to the randomization status (high or low protein) of the matched trial participants. Results Trial participants were generally heavier, had larger waist circumference and larger fat mass than the participants in the entire DCH cohort. A better weight maintenance in the high-protein group compared to the low protein group was observed in the subgroups of the DCH cohort matching body characteristics of the trial participants. Conclusion This modified observational study, minimized the differences between the RCT and observational data with regard to dietary intake, participant characteristics and statistical analysis. Compared with low protein diet the high protein diet was associated with better weight maintenance when individuals with greater body mass index and waist circumference were analyzed. Selecting subsets of large-scale observational cohort studies with similar characteristics as participants in clinical trials

  4. Unintentional child neglect: literature review and observational study.

    PubMed

    Friedman, Emily; Billick, Stephen B

    2015-06-01

    Child abuse is a problem that affects over six million children in the United States each year. Child neglect accounts for 78% of those cases. Despite this, the issue of child neglect is still not well understood, partially because child neglect does not have a consistent, universally accepted definition. Some researchers consider child neglect and child abuse to be one in the same, while other researchers consider them to be conceptually different. Factors that make child neglect difficult to define include: (1) Cultural differences; motives must be taken into account because parents may believe they are acting in the child's best interests based on cultural beliefs (2) the fact that the effect of child abuse is not always immediately visible; the effects of emotional neglect specifically may not be apparent until later in the child's development, and (3) the large spectrum of actions that fall under the category of child abuse. Some of the risk factors for increased child neglect and maltreatment have been identified. These risk factors include socioeconomic status, education level, family composition, and the presence of dysfunction family characteristics. Studies have found that children from poorer families and children of less educated parents are more likely to sustain fatal unintentional injuries than children of wealthier, better educated parents. Studies have also found that children living with adults unrelated to them are at increased risk for unintentional injuries and maltreatment. Dysfunctional family characteristics may even be more indicative of child neglect. Parental alcohol or drug abuse, parental personal history of neglect, and parental stress greatly increase the odds of neglect. Parental depression doubles the odds of child neglect. However, more research needs to be done to better understand these risk factors and to identify others. Having a clearer understanding of the risk factors could lead to prevention and treatment, as it would allow

  5. Unintentional child neglect: literature review and observational study.

    PubMed

    Friedman, Emily; Billick, Stephen B

    2015-06-01

    Child abuse is a problem that affects over six million children in the United States each year. Child neglect accounts for 78% of those cases. Despite this, the issue of child neglect is still not well understood, partially because child neglect does not have a consistent, universally accepted definition. Some researchers consider child neglect and child abuse to be one in the same, while other researchers consider them to be conceptually different. Factors that make child neglect difficult to define include: (1) Cultural differences; motives must be taken into account because parents may believe they are acting in the child's best interests based on cultural beliefs (2) the fact that the effect of child abuse is not always immediately visible; the effects of emotional neglect specifically may not be apparent until later in the child's development, and (3) the large spectrum of actions that fall under the category of child abuse. Some of the risk factors for increased child neglect and maltreatment have been identified. These risk factors include socioeconomic status, education level, family composition, and the presence of dysfunction family characteristics. Studies have found that children from poorer families and children of less educated parents are more likely to sustain fatal unintentional injuries than children of wealthier, better educated parents. Studies have also found that children living with adults unrelated to them are at increased risk for unintentional injuries and maltreatment. Dysfunctional family characteristics may even be more indicative of child neglect. Parental alcohol or drug abuse, parental personal history of neglect, and parental stress greatly increase the odds of neglect. Parental depression doubles the odds of child neglect. However, more research needs to be done to better understand these risk factors and to identify others. Having a clearer understanding of the risk factors could lead to prevention and treatment, as it would allow

  6. Gender differences in young children’s temperament traits: Comparisons across observational and parent-report methods

    PubMed Central

    Olino, Thomas M.; Durbin, C. Emily; Klein, Daniel N.; Hayden, Elizabeth P.; Dyson, Margaret W.

    2012-01-01

    Objective Evidence supporting the continuity between child temperament and adult personality traits is accumulating. One important indicator of continuity is the presence of reliable gender differences in traits across the lifespan. A substantial literature demonstrates gender differences on certain adult personality traits and recent meta-analytic work on child samples suggests similar gender differences for some broad and narrow domains of temperament. However, most existing studies of children rely only on parent-report measures. The present study investigated gender differences in temperament traits assessed by laboratory observation, maternal-report, and paternal-report measures. Methods Across three independent samples, behavioral observations, maternal-report, and paternal-report measures of temperament were collected on 463 boys and 402 girls. Results Across all three methods, girls demonstrated higher positive affect and fear and lower activity level than boys. For laboratory measures, girls demonstrated higher levels of sociability and lower levels of overall negative emotionality (NE), sadness, anger and impulsivity than boys. However, girls demonstrated higher levels of overall NE and sadness than boys when measured by maternal reports. Finally, girls demonstrated lower levels of sociability based on paternal reports. Conclusions Results are discussed in relation to past meta-analytic work and developmental implications of the findings. PMID:22924826

  7. Heavy metals and neurodegenerative diseases: an observational study.

    PubMed

    Giacoppo, Sabrina; Galuppo, Maria; Calabrò, Rocco Salvatore; D'Aleo, Giangaetano; Marra, Angela; Sessa, Edoardo; Bua, Daniel Giuseppe; Potortì, Angela Giorgia; Dugo, Giacomo; Bramanti, Placido; Mazzon, Emanuela

    2014-11-01

    In this study, we evaluated the levels of some of the most investigated metals (Cu, Se, Zn, Pb, and Hg) in the blood of patients affected by the most common chronic neurodegenerative diseases like Alzheimer's disease (AD) and multiple sclerosis (MS), in order to better clarify their involvement. For the first time, we investigated a Sicilian population living in an area exposed to a potentially contaminated environment from dust and fumes of volcano Etna and consumer of a considerable quantity of fish in their diet, so that this represents a good cohort to demonstrate a possible link between metals levels and development of neurodegenerative disorders. More specifically, 15 patients affected by AD, 41 patients affected by MS, 23 healthy controls, and 10 healthy elderly controls were recruited and subjected to a venous blood sampling. Quantification of heavy metals was performed by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). This technique has allowed us to establish that there is a concomitance of heavy metal unbalance associated with AD more than in other neurodegenerative pathologies, such as MS. Also, we can assess that the concentration of these elements is independent from the diet, especially from occasional or habitual consumption of fruits and vegetables, prevalence in the diet of meat or fish, possible exposure to contaminated environment due both to the occupation and place of residence.

  8. [Observation and study on atmospheric VOCs in Changsha city].

    PubMed

    Liu, Quan; Wang, Yue-Si; Wu, Fang-Kun; Sun, Jie

    2011-12-01

    Volatile organic compounds (VOCs) are one of the key precursors of atmospheric ozone (O3), which also contribute to the production of SOA. During 2008, VOCs were measured near Changsha City. Weekly integrated canister samples were collected and analyzed in the morning and afternoon of each Tuesday. Simultaneously, concentration, potential ozone production and sources of VOCs in the atmosphere of Changsha were studied. The results indicated that the total VOCs species had higher concentrations in the morning (38.4 x 10(-9)), and lower in the afternoon (22.7 x 10(-9)), where the concentration of halo carbon was the highest, and alkanes, aromatics and alkenes came next. The m/p-xylene had the highest OH reactivity concentration (10.71 x 10(-9) C), 1,2,4-trimethylbenzene (6.04 x 10(-9) C) and 1,3,5-trimethylbenzene (2.23 x 10(-9) C) came next. Aromatics (66%) had the most significant contribution to the production of O3 in the atmospheric VOCs of Changsha, and alkenes (26%) and alkanes (8%) came next. The highest concentrations of propane and isopentane indicated vehicular exhaust and liquefied petroleum gas (LPG) appear to be the main source of VOCs in Changsha City. Benzene/toluene ratio was higher than 0.5 which was close to 0.8, showing solvent volatilization was also a main source of VOCs.

  9. RISR Observations of High Ion Temperatures: A Case Study

    NASA Astrophysics Data System (ADS)

    Akbari, H.; Semeter, J. L.

    2015-12-01

    Incoherent scatter radars (ISRs) measure the frequency spectrum of the scattered signal from random thermal fluctuations in the ionospheric plasma. Once fitted to a theoretical model, the shape of the spectrum provides estimates to a number of plasma parameters including the ion temperature. The theoretical models of the frequency spectrum of the scattered signal have been often developed based on a set of assumptions on the state of the plasma. One of the most common assumptions is that the plasma is in thermal equilibrium consisting of electron and ion populations that can be described by Maxwellian distributions. Such an assumption, however, is commonly violated at high latitudes where the interactions between the ionosphere and the magnetosphere result in a very dynamic plasma environment. One example of such violations occurs on the edge of auroral arcs when the presence of strong electric fields (<100 mV/m) may cause the ion velocity distribution to deviate from Maxwellian. In such cases, the assumption of thermal equilibrium in the standard ISR fitting procedure results in significant errors in derivation of the plasma parameters. In this study we investigate an event in which the ion temperature measured by the Resolute Bay incoherent scatter radar (RISR) reaches to values as high as 8000 (K). Based on RISR measurements of the electric fields we calculate the expected Joule heating and investigate the possible role of ISR misfitting (caused by deviation of the ion distribution from Maxwellian) in over estimating the ion temperature.

  10. [Quality of the clinical reports: observational study in Sassari].

    PubMed

    Virdis, A; Licheri, N; Ruiu, A

    2009-01-01

    Within the program of clinical risk management, and in particular in the phase of the "knowledge" of company reality, the work deals with the topic of the case history in Sassari' local health authority. A study is treated where, on a sample of about 400 cases history, four definite aspects are considered, in particular those that are regarded as the most important in the risk management and about medical responsability: 1) formal consent; 2) daily clinical allowance; 3) therapeutic card; 4) operating card. The results we got show the presence of a formal consent filled in correctly in 36 cases (9%), completed a daily allowance in 36 cases (9%), therapeutic card in 14 (3.5%) cases, operation card in 21 cases (19% su 116 surgical cases). These data, that have permitted to estimate the specific company reality as from pointed out critical states, show the necessity of working, with involvement of professional doctors, to build a history case model with clear and shared rules where you can clearly find the clinical path of a patient, where everything made is quoted and easily readable when necessary.

  11. Observation of 2D Ising criticality of liquid-gas transition by the flowgram method

    NASA Astrophysics Data System (ADS)

    Yarmolinsky, Max; Kuklov, Anatoly

    We study the critical properties of the transition in 2D liquid-gas system with the square-well potential interaction by Monte Carlo simulations in the grand canonical ensemble. Due to lack of the underlying Ising symmetry, the analysis cannot be done reliably by the standard methods applicable to lattice systems. In contrast, the analysis based on the flowgram method allowed us to find the critical point to significantly higher (and controllable) accuracy than in previous studies by other authors. Simulations were performed in a progression of sizes L up to size L = 84 , with the particle numbers varying over 3 orders of magnitude and the subcritical behavior not extending beyond L = 10 - 15 . The finite size scaling analysis of the critical exponents and their ratio, μ and γ / ν , gives values consistent with the 2D Ising universality class within 1-2% of errors. Our result essentially closes proposals that the nature of the liquid-gas transition might be different from the Ising model in systems with short-range interactions. This work was supported by the NSF Grant PHY1314469.

  12. The pursuit of clinical truth: role of epidemiology/observation studies.

    PubMed

    Spector, R; Vesell, E S

    2000-11-01

    The need for evidence-based medicine as a foundation for optimal patient care requires application of the best scientific methods. Various methods used in the search for clinical truth are discussed. The most powerful method to test a clinical hypothesis is the randomized, controlled clinical trial. By contrast, epidemiology/observation studies (EOS) have inherent weaknesses that can lead to erroneous conclusions. Five such examples, two older and three very recent, are discussed to provide historical perspective and demonstrate potential problems with EOS. Each incident has produced widespread consternation or confusion among physicians. Types of bias leading to errors in EOS are discussed, and the need is emphasized for more rigorous evaluation of EOS by investigators, as well as editors, to avoid repetition of past mistakes and to ensure publication of correct medical information.

  13. Atmospheric sounding by GPS radio occultation: Simulation studies and comparisons with observations

    NASA Astrophysics Data System (ADS)

    Beyerle, G.; Gorbunov, M. E.; Ao, C. O.; Wickert, J.; Schmidt, T.; Reigber, Ch.

    2003-04-01

    Within the first two years following the activation of the GPS radio occultation experiment aboard the geoscience satellite CHAMP more than~100,000 occultation events have been observed. Between 70 and 80% of these observations were successfully processed to yield vertical profiles of atmospheric refractivity, temperature and humidity. In the upper troposphere and stratosphere the derived atmospheric refractivities agree with ECMWF meteorological analyses to better than 0.5%; in the lower troposphere, however, a negative bias exceeding several percent is observed. End-to-end simulation studies were performed to investigate possible causes for the observed refractivity bias. Using the multiple phase screen method C/A-code modulated L1 signals are propagated through a spherically symmetric refractivity field derived from a high-resolution radio sonde observation. The propagated signals are tracked by a software GPS receiver and converted to refractivity profiles using the canonical transform technique and the Abel inversion. Ignoring noise and assuming an ideal receiver tracking behaviour the true refractivity profiles are reproduced to better than 0.1% at altitude above 2~km. The non-ideal case is simulated by adding between 14 and 24~dB of Gaussian white noise to the signal and tracking the signal with receivers operating at 50 and 200~Hz sampling frequency using two different carrier phase detectors. In the upper troposphere and stratosphere the receiver models reproduce the true refractivity profile to better than 0.1%. However, in the mid-troposphere down to altitudes of about 2~km a Costas-type phase-locked loop tracking induces negative refractivity biases on the order of~-1~to~-2% at 50~Hz sampling frequency. Modifications to the receiver tracking algorithm improve the retrieved signal significantly. Based on these simulation results a heuristic procedure based on the canonical transform method and the sliding spectral technique is proposed. The procedure is

  14. Observations of liver cancer cells in scanning probe acoustic microscope: a preliminary study

    NASA Astrophysics Data System (ADS)

    Chen, Xiaohui; Fang, Xiaoyue; Xi, Qing; Guo, Hua; Zhang, Ning; Ding, Mingyue

    2016-04-01

    Scanning probe acoustic microscope (SPAM) can be used to acquire the morphology image as well as the non-destructive internal structures acoustic image. However, the observations of the morphology image as well as the internal structures acoustic image of liver cancer cells in SPAM are few. In this paper, we cultured 4 different types of liver cancer cells on the silicon wafer and coverslip to observe their morphology images as well as acoustic images in SPAM, and made a preliminary study of the 8 types of cells specimens (hereinafter referred to as the silicon specimens and coverslips specimens). The experimental measurement results showed that some cellular pseudopodium were observed in the morphology images of the coverslip specimens while no such cellular pseupodium were appeared in the morphology images of the silicon specimens, which concluded that the living liver cancer cells were less likely to grow on the silicon wafer. SPAM provides a rapid and sensitive visual method for studying the morphology and internal structures of the cancer cells. The proposed method can be also used to obtain the morphology and internal information in both solid and soft material wafers, such as silicon and cells, with the resolution of nanometer scale.

  15. Occasions and the Reliability of Classroom Observations: Alternative Conceptualizations and Methods of Analysis

    ERIC Educational Resources Information Center

    Meyer, J. Patrick; Cash, Anne H.; Mashburn, Andrew

    2011-01-01

    Student-teacher interactions are dynamic relationships that change and evolve over the course of a school year. Measuring classroom quality through observations that focus on these interactions presents challenges when observations are conducted throughout the school year. Variability in observed scores could reflect true changes in the quality of…

  16. An Observational Study of Group Waterpipe Use in a Natural Environment

    PubMed Central

    2014-01-01

    Introduction: To date research on tobacco smoking with a waterpipe (hookah, narghile, and shisha) has focused primarily on the individual user in a laboratory setting. Yet, waterpipe tobacco smoking is often a social practice that occurs in cafés, homes, and other natural settings. This observational study examined the behavior of waterpipe tobacco smokers and the social and contextual features of waterpipe use among groups in their natural environment. Methods: Trained observers visited urban waterpipe cafés on multiple occasions during an 8-month period. Observations of 241 individual users in naturally formed groups were made on smoking topography (puff frequency, duration, and interpuff interval [IPI]) and engagement in other activities (e.g., food and drink consumption, other tobacco use, and media viewing). Results: Most users were male in group sizes of 3–4 persons, on average, and each table had 1 waterpipe, on average. The predominant social features during observational periods were conversation and nonalcoholic drinking. Greater puff number was associated with smaller group sizes and more waterpipes per group, while longer IPIs were associated with larger group sizes and fewer waterpipes per group. Additionally, greater puff frequency was observed during media viewing and in the absence of other tobacco use. Conclusions: Overall, the results suggest that waterpipe smoking behavior is affected by group size and by certain social activities. Discussion focuses on how these findings enhance our understanding of factors that may influence exposure to waterpipe tobacco smoke toxicants in naturalistic environments. PMID:23943842

  17. What Happens During a Minor Flood: Observations of Bedload Transport in a Gravel Bed River using New Methods

    NASA Astrophysics Data System (ADS)

    Bray, E. N.; Dunne, T.

    2015-12-01

    The question of "does the streambed change over a flood" does not have a clear answer due to lack of measurement methods during high flows. We seek to inform our understanding of bedload transport by linking field measurements using fiber optic distributed temperature sensing (DTS) cable, calculations of disentrainment over time and distance, and in situ measurements of streambed permeability with sediment transport theory and an existing explicit analytical solution to predict depth of sediment deposition and one-dimensional fluid velocity from amplitude and phase information. The method facilitates the study of gravel transport by using near-bed temperature time series to estimate rates of sediment deposition continuously over the duration of a minor flood coinciding with bar formation, including (1) a field method for measuring local rates of deposition and bed elevation change during a minor flood to compute rates of bedload transport, (2) use of an existing analytical solution to quantify the depth of sediment deposition over distance and time from temperature amplitude and phase information, (3) observational and theoretical evidence that incipient motion occurs during a minor flood, (4) observational evidence that suggests rates of sediment transport are not necessarily constant during a constant flow, and (5) field evidence for the persistence of armor layers in gravel bed rivers during a minor flood. These observations of partial bedload transport, taken along a 2 km gravel bed reach of the San Joaquin River, CA, USA during an experimental flow release, suggest that the discharge needed to create the boundary shear is lower than previous estimates, and that partial transport of grain sizes on the bed, including the median particle size, occurs during a minor flood with a current recurrence interval of approximately 1-2 years.

  18. Fireball observations in central Europe and western Australia: instruments, methods, and results

    NASA Astrophysics Data System (ADS)

    Spurny, P.

    2012-01-01

    Penetration of larger meteoroids through the atmosphere which gives rise to spectacular luminous events - fireballs or even superbolides - is of the greatest interest. Their registrations, especially photographic and newly also photoelectric recordings, provide excellent means to examine physical properties as well as the temporal and spatial distribution of extraterrestrial matter in near-Earth space. The most efficient tools for registration of these very scarce events are the fireball networks: systems covering large areas of the Earth's surface, with multiple camera stations designed to image a large fraction of the night sky. Such camera networks for fireball observations have been set up in several nations at various times in the past (European Fireball Network (EN) in the Czech Republic, Germany, Austria, and Slovakia; the Prairie Network in the USA; and the Meteorite Observation and Recovery Project (MORP) in Canada). Of these networks, only the European fireball network is still in operation, and this continuously since it was started up, but recently new networks were established in South-West Australia and in Ontario, Canada. The two main scientific aims of all these programs remain the same as in the very beginning - first, to constrain the flux of extraterrestrial material to the Earth over a range of masses, and second, to provide a statistically significant group of meteorites with accurate orbits. This contribution was focused on the current work and some particular recent results from the European Fireball Network, especially from its Czech part (current status is described, for example, by Spurny et al., 2006) and from the Desert Fireball Network in the Nullarbor Plains of South-West Australia (Bland, 2004; Spurny et al., 2012; and Bland et al., 2012). The mode of operation of both networks and the analysis methods used were described in detail and illustrated by some examples. Similarly, the most important recent results, especially from the

  19. Cruciferous vegetables intake and the risk of colorectal cancer: a meta-analysis of observational studies

    PubMed Central

    Wu, Q. J.; Yang, Y.; Vogtmann, E.; Wang, J.; Han, L. H.; Li, H. L.; Xiang, Y. B.

    2013-01-01

    Background Epidemiological studies have reported inconsistent associations between cruciferous vegetable (CV) intake and colorectal cancer (CRC) risk. To our knowledge, a comprehensive and quantitative assessment of the association between CV intake and CRC has not been reported. Methods Relevant articles were identified by searching MEDLINE. We pooled the relative risks (RR) from individual studies using a random-effect model and carried out heterogeneity and publication bias analyses. Results Twenty-four case–control and 11 prospective studies were included in our analysis. When all studies were pooled, we yielded a significantly inverse association between CV (RR: 0.82; 95% confidence interval 0.75–0.90) intake and CRC risk. Specific analysis for cabbage and broccoli yielded similar result. When separately analyzed, case–control studies of CV intake yield similar results, and the results from the prospective studies showed borderline statistical significance. Moreover, significant inverse associations were also observed in colon cancer and its distal subsite both among prospective and case–control studies. Conclusions Findings from this meta-analysis provide evidence that high intake of CV was inversely associated with the risk of CRC and colon cancer in humans. Further analysis on other specific CV, food preparation methods, stratified results by anatomic cancer site, and subsite of colon cancer should be extended in future study. PMID:23211939

  20. Opportunity for interaction? A naturalistic observation study of dual-earner families after work and school.

    PubMed

    Campos, Belinda; Graesch, Anthony P; Repetti, Rena; Bradbury, Thomas; Ochs, Elinor

    2009-12-01

    Everyday patterns of interaction can strengthen or undermine bonds between family members. This naturalistic observation study focused on an understudied facet of family life: opportunities for interaction among dual-earner family members after work and family members' responses to these opportunities. Thirty dual-earner couples and their children were observed and video-recorded in their homes throughout two weekday afternoons and evenings. Two interaction opportunities were analyzed: (1) the behavior of family members toward a parent returning home from work and (2) the physical proximity of family members throughout the evening. Three main findings emerged. Women, who tended to return home before men, were greeted with positive behavior and reports of the day's information from family members. Men, in contrast, returned home later in the day and received positive behavior or no acknowledgment from family members distracted by other activities. Throughout the evening, mothers spent more time with children whereas fathers spent more time alone. Couples were seldom together without their children. The implications of observed interaction patterns and the contribution of naturalistic observation methods to the study of family relationships are discussed.

  1. Acoustic streaming in lithotripsy fields: preliminary observation using a particle image velocimetry method.

    PubMed

    Choi, Min Joo; Doh, Doeg Hee; Hwang, Tae Gyu; Cho, Chu Hyun; Paeng, Dong Guk; Rim, Gun Hee; Coleman, A J

    2006-02-01

    This study considers the acoustic streaming in water produced by a lithotripsy pulse. Particle image velocimetry (PIV) method was employed to visualize the acoustic streaming produced by an electromagnetic shock wave generator using video images of the light scattering particles suspended in water. Visualized streaming features including several local peaks and vortexes around or at the beam focus were easily seen with naked eyes over all settings of the lithotripter from 10 to 18 kV. Magnitudes of the peak streaming velocity measured vary in the range of 10-40 mm s(-1) with charging voltage settings. Since the streaming velocity was estimated on the basis of a series of the video images of particles averaged over 1/60s, the time resolution limited by the video frame rate which is 1-2 orders of magnitude larger than driving acoustic activities, measured velocities are expected to be underestimated and were shown a similar order of magnitude lower than those calculated from a simple theoretical consideration. Despite such an underestimation, it was shown that, as predicted by theory, the magnitude of the streaming velocity measured by the present PIV method was proportional to acoustic intensity. In particular it has almost a linear correlation with peak negative pressures (r=0.98683, p=0.0018). PMID:16376400

  2. High speed Infrared imaging method for observation of the fast varying temperature phenomena

    NASA Astrophysics Data System (ADS)

    Moghadam, Reza; Alavi, Kambiz; Yuan, Baohong

    With new improvements in high-end commercial R&D camera technologies many challenges have been overcome for exploring the high-speed IR camera imaging. The core benefits of this technology is the ability to capture fast varying phenomena without image blur, acquire enough data to properly characterize dynamic energy, and increase the dynamic range without compromising the number of frames per second. This study presents a noninvasive method for determining the intensity field of a High Intensity Focused Ultrasound Device (HIFU) beam using Infrared imaging. High speed Infrared camera was placed above the tissue-mimicking material that was heated by HIFU with no other sensors present in the HIFU axial beam. A MATLAB simulation code used to perform a finite-element solution to the pressure wave propagation and heat equations within the phantom and temperature rise to the phantom was computed. Three different power levels of HIFU transducers were tested and the predicted temperature increase values were within about 25% of IR measurements. The fundamental theory and methods developed in this research can be used to detect fast varying temperature phenomena in combination with the infrared filters.

  3. A novel nonintrusive method to resolve the thermal dome effect of pyranometers: Instrumentation and observational basis

    NASA Astrophysics Data System (ADS)

    Ji, Qiang; Tsay, Si-Chee

    2010-04-01

    A new method for improving the ground-based pyranometer measurements of solar irradiance has been employed during the East Asian Study of Tropospheric Aerosols and Impact on Regional Climate field experiment, Asian Monsoon Year in China in 2008. Depending on the temperature difference between its detector and domes, a pyranometer's thermal dome effect (TDE) can vary from a few W m-2 at night to over tens of W m-2 during daytime. Yet in traditional calibration procedures only a single calibration constant is determined, and consequently TDE is misrepresented. None of the methods that have been documented in the literature can capture TDE nonintrusively using the same instrument. For example, although adding a temperature sensor to the detector assembly is straightforward, attaching any sensor on a dome is intrusive and will affect its overall optical and physical properties. Furthermore, in response to the solar elevation and atmospheric variables, the dome temperature distribution is both dynamic and uneven, which makes it exceedingly difficult for locating a representative point on the dome for measuring TDE. However, the effective-dome-temperature is proportional to the pressure of the air trapped between the outer and the inner domes; therefore with a minor modification to a pyranometer, we can utilize the ideal gas law to gauge TDE without affecting the domes. Pyranometers can become climate-quality instruments once their TDE are nonintrusively determined.

  4. First Year Wilkinson Microwave Anisotropy Probe(WMAP) Observations: Data Processing Methods and Systematic Errors Limits

    NASA Technical Reports Server (NTRS)

    Hinshaw, G.; Barnes, C.; Bennett, C. L.; Greason, M. R.; Halpern, M.; Hill, R. S.; Jarosik, N.; Kogut, A.; Limon, M.; Meyer, S. S.

    2003-01-01

    We describe the calibration and data processing methods used to generate full-sky maps of the cosmic microwave background (CMB) from the first year of Wilkinson Microwave Anisotropy Probe (WMAP) observations. Detailed limits on residual systematic errors are assigned based largely on analyses of the flight data supplemented, where necessary, with results from ground tests. The data are calibrated in flight using the dipole modulation of the CMB due to the observatory's motion around the Sun. This constitutes a full-beam calibration source. An iterative algorithm simultaneously fits the time-ordered data to obtain calibration parameters and pixelized sky map temperatures. The noise properties are determined by analyzing the time-ordered data with this sky signal estimate subtracted. Based on this, we apply a pre-whitening filter to the time-ordered data to remove a low level of l/f noise. We infer and correct for a small (approx. 1 %) transmission imbalance between the two sky inputs to each differential radiometer, and we subtract a small sidelobe correction from the 23 GHz (K band) map prior to further analysis. No other systematic error corrections are applied to the data. Calibration and baseline artifacts, including the response to environmental perturbations, are negligible. Systematic uncertainties are comparable to statistical uncertainties in the characterization of the beam response. Both are accounted for in the covariance matrix of the window function and are propagated to uncertainties in the final power spectrum. We characterize the combined upper limits to residual systematic uncertainties through the pixel covariance matrix.

  5. Predictive Factors for Anastomotic Leakage After Colorectal Surgery: Study Protocol for a Prospective Observational Study (REVEAL Study)

    PubMed Central

    Bosmans, Joanna WAM; Kartal, Serdar; Lubbers, Tim; Sosef, Meindert; Slooter, Gerrit D; Stoot, Jan H; van Schooten, Frederik-Jan; Bouvy, Nicole D; Derikx, Joep PM

    2016-01-01

    Background Anastomotic leakage (AL) remains the most important complication following colorectal surgery, and is associated with high morbidity and mortality rates. Previous research has focused on identifying risk factors and potential biomarkers for AL, but the sensitivity of these tests remains poor. Objective This prospective multicenter observational study aims at combining multiple parameters to establish a diagnostic algorithm for colorectal AL. Methods This study aims to include 588 patients undergoing surgery for colorectal carcinoma. Patients will be eligible for inclusion when surgery includes the construction of a colorectal anastomosis. Patient characteristics will be collected upon consented inclusion, and buccal swabs, breath, stool, and blood samples will be obtained prior to surgery. These samples will allow for the collection of information regarding patients’ inflammatory status, genetic predisposition, and intestinal microbiota. Additionally, breath and blood samples will be taken postoperatively and patients will be strictly observed during their in-hospital stay, and the period shortly thereafter. Results This study has been open for inclusion since August 2015. Conclusions An estimated 8-10% of patients will develop AL following surgery, and they will be compared to non-leakage patients. The objectives of this study are twofold. The primary aim is to establish and validate a diagnostic algorithm for the pre-operative prediction of the risk of AL development using a combination of inflammatory, immune-related, and genetic parameters. Previously established risk factors and novel parameters will be incorporated into this algorithm, which will aid in the recognition of patients who are at risk for AL. Based on these results, recommendations can be made regarding the construction of an anastomosis or deviating stoma, and possible preventive strategies. Furthermore, we aim to develop a new algorithm for the post-operative diagnosis of AL at an

  6. In operandi observation of dynamic annealing: A case study of boron in germanium nanowire devices

    SciTech Connect

    Koleśnik-Gray, Maria M.; Krstić, Vojislav; Sorger, Christian; Weber, Heiko B.; Biswas, Subhajit; Holmes, Justin D.

    2015-06-08

    We report on the implantation of boron in individual, electrically contacted germanium nanowires with varying diameter and present a technique that monitors the electrical properties of a single device during implantation of ions. This method gives improved access to study the dynamic annealing ability of the nanowire at room temperature promoted by its quasi-one-dimensional confinement. Based on electrical data, we find that the dopant activation efficiency is nontrivially diameter dependent. As the diameter decreases, a transition from a pronounced dynamic-annealing to a radiation-damage dominated regime is observed.

  7. Seismic Study of The Solar Interior: Inferences from SOI/MDI Observations during Solar Activity

    NASA Technical Reports Server (NTRS)

    Korzennik, Sylvain G.

    2003-01-01

    The principal investigator describes several types of solar research conducted during the reporting period and gives a statement of work to be performed in the following year. Research conducted during the reporting period includes: exhaustive analysis of observational and instrumental effects that might cause systematic errors in the characterization of high-degree p-modes; study of the structure, asphericity and dynamics of the solar interior from p-mode frequencies and frequency splittings; characterizing the solar rotation; Time-Distance inversion; and developing and using a new peak-fitting method for very long MDI time series at low degrees.

  8. Observations of the solar plasma using radio scattering and scintillation methods

    NASA Technical Reports Server (NTRS)

    Hewish, A.

    1972-01-01

    Observations of the solar plasma using the interplanetary scintillation technique have been made at radial distances of 0.03 to 1.2 AU. The solar wind is found to be independent of ecliptic latitude and radial distance, except close to the sun where acceleration is observed. Plasma density irregularities on a scale near the proton gyro radius, which modulate the mean density by about 1 percent, are present throughout the observed range of radial distance.

  9. Association between Dairy Intake and Gastric Cancer: A Meta-Analysis of Observational Studies

    PubMed Central

    Tian, Shu-bo; Yu, Jian-chun; Kang, Wei-ming; Ma, Zhi-qiang; Ye, Xin; Cao, Zhan-jiang

    2014-01-01

    Purpose Observational studies have given inconsistent findings on the relationship between intake of dairy products and gastric cancer. We therefore conducted a systematic review with a meta-analysis of observational studies to summarize available evidence on this point. Methods We searched the electronic literature databases of PubMed (Medline), EMBASE and the Chinese Biomedical Literature Database up until August 30, 2013. All studies were limited to the English language. Random-effects models were used to pool study results between dairy products consumption and the risk of gastric cancer. We also performed subgroup, publication bias and sensitivity analysis. Results Eight prospective studies and 18 case-control studies were included in our analysis, with a total number of 7272 gastric cancer cases and 223,355 controls. Pooled relative risks of all studies showed no significant association between dairy intake and gastric cancer (odds ratio [OR]: 1.09, 95% confidence interval [CI]: 0.96–1.25). When study design was separately analyzed, population-based case-control studies showed a positive association between dairy intake and gastric cancer risk (OR: 1.36; 95% CI: 1.07–1.74), whereas no associations were shown by hospital-based case-control studies (OR: 0.86, 95% CI: 0.72–1.02) or cohort studies (OR = 1.01, 95% CI = 0.91–1.13). Conclusions The meta-analysis shows that no clear association apparently exists between consumption of dairy products and gastric cancer risk. Further well-designed cohort and intervention studies should be conducted to verify this lack of association. PMID:25006674

  10. An Observational Case Study of Near-peer Teaching in Medical and Pharmacy Experiential Training

    PubMed Central

    Sharif-Chan, Bayan; Tankala, Dipti; Leong, Christine; Austin, Zubin

    2016-01-01

    Objective. To compare peer teaching in a medical and a pharmacy clinical teaching unit and to provide suggestions for future research in pharmacy near-peer teaching. Methods. This exploratory observational study used principles of ethnographic methodology for data collection and analysis. Observations were collected in a large downtown teaching hospital. An average of 4-6 hours per day were spent observing a team of medical trainees from the Faculty (School) of Medicine in the general internal medicine (unit for two weeks, followed by a team of pharmacy trainees in an ambulatory hemodialysis (HD) unit for two weeks. Data was collected through field notes and informal interviews that were audiotaped and subsequently transcribed. Data was interpreted by the observer and reviewed weekly by two impartial pharmacists. Results. Five major themes emerged: (1) influence of peer teaching hierarchy; (2) educational distance between peer learners and teachers; (3) effect of the clinical teaching unit size on peer learning; (4) trainees’ perception of their teaching role in the clinical teaching unit; and (5) influence of daily schedule and workload on peer teaching. As opposed to pharmacy, a hierarchy and pyramidal structure of peer teaching was observed in medical experiential training. There appeared to be no effect of educational distance on near peer teaching; however, perception of teaching role and influence of daily schedule affected near-peer teaching. Conclusion. Through initial comparisons of medical and pharmacy clinical teaching units, this study provides a reflection of elements that may be necessary to successfully implement near-peer teaching in pharmacy experiential training. Future studies in this area should assess learning outcomes and participant satisfaction, preceptor workload, and impact on patient care. PMID:27756922

  11. Taguchi methods in electronics: A case study

    NASA Astrophysics Data System (ADS)

    Kissel, R.

    1992-05-01

    Total Quality Management (TQM) is becoming more important as a way to improve productivity. One of the technical aspects of TQM is a system called the Taguchi method. This is an optimization method that, with a few precautions, can reduce test effort by an order of magnitude over conventional techniques. The Taguchi method is specifically designed to minimize a product's sensitivity to uncontrollable system disturbances such as aging, temperature, voltage variations, etc., by simultaneously varying both design and disturbance parameters. The analysis produces an optimum set of design parameters. A 3-day class on the Taguchi method was held at the Marshall Space Flight Center (MSFC) in May 1991. A project was needed as a follow-up after the class was over, and the motor controller was selected at that time. Exactly how to proceed was the subject of discussion for some months. It was not clear exactly what to measure, and design kept getting mixed with optimization. There was even some discussion about why the Taguchi method should be used at all.

  12. Exploring the "Sharkcano": Biogeochemical observations of the Kavachi submarine volcano (Solomon Islands) using simple, cost-effective methods.

    NASA Astrophysics Data System (ADS)

    Phillips, B. T.; Albert, S.; Carey, S.; DeCiccio, A.; Dunbabin, M.; Flinders, A. F.; Grinham, A. R.; Henning, B.; Howell, C.; Kelley, K. A.; Scott, J. J.

    2015-12-01

    Kavachi is a highly active undersea volcano located in the Western Province of the Solomon Islands, known for its frequent phreatomagmatic eruptions and ephemeral island-forming activity. The remote location of Kavachi and its explosive behavior has restricted scientific exploration of the volcano, limiting observations to surface imagery and peripheral water-column data. An expedition to Kavachi in January 2015 was timed with a rare lull in volcanic activity, allowing for observation of the inside of Kavachi's caldera and its flanks. Here we present medium-resolution bathymetry of the main peak paired with benthic imagery, petrologic analysis of samples from the caldera rim, measurements of gas flux over the main peak, and hydrothermal plume structure data. A second peak was discovered to the Southwest of the main cone and displayed evidence of diffuse-flow venting. Populations of gelatinous animals, small fish, and sharks were observed inside the active crater, raising new questions about the ecology of active submarine volcanoes. Most equipment used in this study was lightweight, relatively low-cost, and deployed using small boats; these methods may offer developing nations an economic means to explore deep-sea environments within their own territorial waters.

  13. A comparison of methods for smoothing and gap filling time series of remote sensing observations - application to MODIS LAI products

    NASA Astrophysics Data System (ADS)

    Kandasamy, S.; Baret, F.; Verger, A.; Neveux, P.; Weiss, M.

    2013-06-01

    Moderate resolution satellite sensors including MODIS (Moderate Resolution Imaging Spectroradiometer) already provide more than 10 yr of observations well suited to describe and understand the dynamics of earth's surface. However, these time series are associated with significant uncertainties and incomplete because of cloud cover. This study compares eight methods designed to improve the continuity by filling gaps and consistency by smoothing the time course. It includes methods exploiting the time series as a whole (iterative caterpillar singular spectrum analysis (ICSSA), empirical mode decomposition (EMD), low pass filtering (LPF) and Whittaker smoother (Whit)) as well as methods working on limited temporal windows of a few weeks to few months (adaptive Savitzky-Golay filter (SGF), temporal smoothing and gap filling (TSGF), and asymmetric Gaussian function (AGF)), in addition to the simple climatological LAI yearly profile (Clim). Methods were applied to the MODIS leaf area index product for the period 2000-2008 and over 25 sites showed a large range of seasonal patterns. Performances were discussed with emphasis on the balance achieved by each method between accuracy and roughness depending on the fraction of missing observations and the length of the gaps. Results demonstrate that the EMD, LPF and AGF methods were failing because of a significant fraction of gaps (more than 20%), while ICSSA, Whit and SGF were always providing estimates for dates with missing data. TSGF (Clim) was able to fill more than 50% of the gaps for sites with more than 60% (80%) fraction of gaps. However, investigation of the accuracy of the reconstructed values shows that it degrades rapidly for sites with more than 20% missing data, particularly for ICSSA, Whit and SGF. In these conditions, TSGF provides the best performances that are significantly better than the simple Clim for gaps shorter than about 100 days. The roughness of the reconstructed temporal profiles shows large

  14. A comparison of methods for smoothing and gap filling time series of remote sensing observations: application to MODIS LAI products

    NASA Astrophysics Data System (ADS)

    Kandasamy, S.; Baret, F.; Verger, A.; Neveux, P.; Weiss, M.

    2012-12-01

    Moderate resolution satellite sensors including MODIS already provide more than 10 yr of observations well suited to describe and understand the dynamics of the Earth surface. However, these time series are incomplete because of cloud cover and associated with significant uncertainties. This study compares eight methods designed to improve the continuity by filling gaps and the consistency by smoothing the time course. It includes methods exploiting the time series as a whole (Iterative caterpillar singular spectrum analysis (ICSSA), empirical mode decomposition (EMD), low pass filtering (LPF) and Whittaker smoother (Whit)) as well as methods working on limited temporal windows of few weeks to few months (Adaptive Savitzky-Golay filter (SGF), temporal smoothing and gap filling (TSGF) and asymmetric Gaussian function (AGF)) in addition to the simple climatological LAI yearly profile (Clim). Methods were applied to MODIS leaf area index product for the period 2000-2008 over 25 sites showing a large range of seasonal patterns. Performances were discussed with emphasis on the balance achieved by each method between accuracy and roughness depending on the fraction of missing observations and the length of the gaps. Results demonstrate that EMD, LPF and AGF methods were failing in case of significant fraction of gaps (%Gap > 20%), while ICSSA, Whit and SGF were always providing estimates for dates with missing data. TSGF (respectively Clim) was able to fill more than 50% of the gaps for sites with more than 60% (resp. 80%) fraction of gaps. However, investigation of the accuracy of the reconstructed values shows that it degrades rapidly for sites with more than 20% missing data, particularly for ICSSA, Whit and SGF. In these conditions, TSGF provides the best performances significantly better than the simple Clim for gaps shorter than about 100 days. The roughness of the reconstructed temporal profiles shows large differences between the several methods, with a decrease

  15. Statistical Track-Before-Detect Methods Applied to Faint Optical Observations of Resident Space Objects

    NASA Astrophysics Data System (ADS)

    Fujimoto, K.; Yanagisawa, T.; Uetsuhara, M.

    Automated detection and tracking of faint objects in optical, or bearing-only, sensor imagery is a topic of immense interest in space surveillance. Robust methods in this realm will lead to better space situational awareness (SSA) while reducing the cost of sensors and optics. They are especially relevant in the search for high area-to-mass ratio (HAMR) objects, as their apparent brightness can change significantly over time. A track-before-detect (TBD) approach has been shown to be suitable for faint, low signal-to-noise ratio (SNR) images of resident space objects (RSOs). TBD does not rely upon the extraction of feature points within the image based on some thresholding criteria, but rather directly takes as input the intensity information from the image file. Not only is all of the available information from the image used, TBD avoids the computational intractability of the conventional feature-based line detection (i.e., "string of pearls") approach to track detection for low SNR data. Implementation of TBD rooted in finite set statistics (FISST) theory has been proposed recently by Vo, et al. Compared to other TBD methods applied so far to SSA, such as the stacking method or multi-pass multi-period denoising, the FISST approach is statistically rigorous and has been shown to be more computationally efficient, thus paving the path toward on-line processing. In this paper, we intend to apply a multi-Bernoulli filter to actual CCD imagery of RSOs. The multi-Bernoulli filter can explicitly account for the birth and death of multiple targets in a measurement arc. TBD is achieved via a sequential Monte Carlo implementation. Preliminary results with simulated single-target data indicate that a Bernoulli filter can successfully track and detect objects with measurement SNR as low as 2.4. Although the advent of fast-cadence scientific CMOS sensors have made the automation of faint object detection a realistic goal, it is nonetheless a difficult goal, as measurements

  16. Attention-Deficit/Hyperactivity Disorder Drugs and Growth: An Italian Prospective Observational Study

    PubMed Central

    Germinario, Elena A.P.; Arcieri, Romano; Bonati, Maurizio; Zuddas, Alessandro; Masi, Gabriele; Vella, Stefano; Chiarotti, Flavia

    2013-01-01

    Abstract Objective This study was conducted to assess the long-term effect of methylphenidate (MPH) or atomoxetine (ATX) on growth in attention-deficit/hyperactivity disorder (ADHD) drug-naïve children. Design The study was an observational, post-marketing, fourth phase study. Methods Data on height and weight were collected at baseline and every 6 months up to 24 months. Results Both ATX and MPH lead to decreased height gain (assessed by means of z-scores); the effect was significantly higher for ATX than for MPH. At any time, height z-score decrease in the ATX group was higher than the corresponding decrease observed in the MPH group, but the difference was significantly relevant only during the first year of treatment. An increment of average weight was observed both in patients treated with MPH and in those treated with ATX. However, using Tanner's percentile, a subset of patients showed a degree of growth lower than expected. This negative effect was significantly higher for ATX than for MPH. Conclusions We conclude that ADHD drugs show a negative effect on linear growth in children in middle term. Such effect appears more evident for ATX than for MPH. PMID:24024538

  17. The REporting of studies Conducted using Observational Routinely-collected health Data (RECORD) Statement

    PubMed Central

    Benchimol, Eric I.; Smeeth, Liam; Guttmann, Astrid; Harron, Katie; Moher, David; Petersen, Irene; Sørensen, Henrik T.; von Elm, Erik; Langan, Sinéad M.

    2015-01-01

    Routinely collected health data, obtained for administrative and clinical purposes without specific a priori research goals, are increasingly used for research. The rapid evolution and availability of these data have revealed issues not addressed by existing reporting guidelines, such as Strengthening the Reporting of Observational Studies in Epidemiology (STROBE). The REporting of studies Conducted using Observational Routinely collected health Data (RECORD) statement was created to fill these gaps. RECORD was created as an extension to the STROBE statement to address reporting items specific to observational studies using routinely collected health data. RECORD consists of a checklist of 13 items related to the title, abstract, introduction, methods, results, and discussion section of articles, and other information required for inclusion in such research reports. This document contains the checklist and explanatory and elaboration information to enhance the use of the checklist. Examples of good reporting for each RECORD checklist item are also included herein. This document, as well as the accompanying website and message board (http://www.record-statement.org), will enhance the implementation and understanding of RECORD. Through implementation of RECORD, authors, journals editors, and peer reviewers can encourage transparency of research reporting. PMID:26440803

  18. Simulation study comparing exposure matching with regression adjustment in an observational safety setting with group sequential monitoring.

    PubMed

    Stratton, Kelly G; Cook, Andrea J; Jackson, Lisa A; Nelson, Jennifer C

    2015-03-30

    Sequential methods are well established for randomized clinical trials (RCTs), and their use in observational settings has increased with the development of national vaccine and drug safety surveillance systems that monitor large healthcare databases. Observational safety monitoring requires that sequential testing methods be better equipped to incorporate confounder adjustment and accommodate rare adverse events. New methods designed specifically for observational surveillance include a group sequential likelihood ratio test that uses exposure matching and generalized estimating equations approach that involves regression adjustment. However, little is known about the statistical performance of these methods or how they compare to RCT methods in both observational and rare outcome settings. We conducted a simulation study to determine the type I error, power and time-to-surveillance-end of group sequential likelihood ratio test, generalized estimating equations and RCT methods that construct group sequential Lan-DeMets boundaries using data from a matched (group sequential Lan-DeMets-matching) or unmatched regression (group sequential Lan-DeMets-regression) setting. We also compared the methods using data from a multisite vaccine safety study. All methods had acceptable type I error, but regression methods were more powerful, faster at detecting true safety signals and less prone to implementation difficulties with rare events than exposure matching methods. Method performance also depended on the distribution of information and extent of confounding by site. Our results suggest that choice of sequential method, especially the confounder control strategy, is critical in rare event observational settings. These findings provide guidance for choosing methods in this context and, in particular, suggest caution when conducting exposure matching.

  19. Park characteristics, use, and physical activity: A review of studies using SOPARC (System for Observing Play and Recreation in Communities).

    PubMed

    Evenson, Kelly R; Jones, Sydney A; Holliday, Katelyn M; Cohen, Deborah A; McKenzie, Thomas L

    2016-05-01

    The System for Observing Play and Recreation in Communities (SOPARC) can obtain information on park users and their physical activity using momentary time sampling. We conducted a literature review of studies using the SOPARC tool to describe the observational methods of each study, and to extract public park use overall and by demographics and physical activity levels. We searched PubMed, Embase, and SPORTDiscus for full-length observational studies published in English in peer-reviewed journals through 2014. Twenty-four studies from 34 articles were included. The number of parks observed per study ranged from 3 to 50. Most studies observed parks during one season. The number of days parks were observed ranged from 1 to 16, with 16 studies observing 5 or more days. All studies included at least one weekday and all but two included at least one weekend day. Parks were observed from 1 to 14times/day, with most studies observing at least 4 times/day. All studies included both morning and afternoon observations, with one exception. There was a wide range of park users (mean 1.0 to 152.6 people/park/observation period), with typically more males than females visiting parks and older adults less than other age groups. Park user physical activity levels varied greatly across studies, with youths generally more active than adults and younger children more active than adolescents. SOPARC was adapted to numerous settings and these review results can be used to improve future studies using the tool, demonstrate ways to compare park data, and inform park promotions and programming. PMID:26946365

  20. Following Experts at Work in Their Own Information Spaces: Using Observational Methods To Develop Tools for the Digital Library.

    ERIC Educational Resources Information Center

    Gorman, Paul; Lavelle, Mary; Delcambre, Lois; Maier, David

    2002-01-01

    Offers an overview of the authors' experience using several observational methods to better understand one class of users, expert clinicians treating patients in hospital settings. Shows the evolution of understanding of the users and their information-handling tasks based on observations made in the field by a multidisciplinary research team, and…

  1. Study report on a double isotope method of calcium absorption

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Some of the pros and cons of three methods to study gastrointestinal calcium absorption are briefly discussed. The methods are: (1) a balance study; (2) a single isotope method; and (3) a double isotope method. A procedure for the double isotope method is also included.

  2. Automated method for study of drug metabolism

    NASA Technical Reports Server (NTRS)

    Furner, R. L.; Feller, D. D.

    1973-01-01

    Commercially available equipment can be modified to provide automated system for assaying drug metabolism by continuous flow-through. System includes steps and devices for mixing drug with enzyme and cofactor in the presence of pure oxygen, dialyzing resulting metabolite against buffer, and determining amount of metabolite by colorimetric method.

  3. Assessment study of lichenometric methods for dating surfaces

    NASA Astrophysics Data System (ADS)

    Jomelli, Vincent; Grancher, Delphine; Naveau, Philippe; Cooley, Daniel; Brunstein, Daniel

    2007-04-01

    In this paper, we discuss the advantages and drawbacks of the most classical approaches used in lichenometry. In particular, we perform a detailed comparison among methods based on the statistical analysis of either the largest lichen diameters recorded on geomorphic features or the frequency of all lichens. To assess the performance of each method, a careful comparison design with well-defined criteria is proposed and applied to two distinct data sets. First, we study 350 tombstones. This represents an ideal test bed because tombstone dates are known and, therefore, the quality of the estimated lichen growth curve can be easily tested for the different techniques. Secondly, 37 moraines from two tropical glaciers are investigated. This analysis corresponds to our real case study. For both data sets, we apply our list of criteria that reflects precision, error measurements and their theoretical foundations when proposing estimated ages and their associated confidence intervals. From this comparison, it clearly appears that two methods, the mean of the n largest lichen diameters and the recent Bayesian method based on extreme value theory, offer the most reliable estimates of moraine and tombstones dates. Concerning the spread of the error, the latter approach provides the smallest uncertainty and it is the only one that takes advantage of the statistical nature of the observations by fitting an extreme value distribution to the largest diameters.

  4. [Preliminary study on pharmacodynamic evaluation method of Houpo formula particles].

    PubMed

    Ma, Lu; Shao, Li-Jie; Tang, Fang

    2014-04-01

    To discuss the feasibility of the pharmacodynamic evaluation method for traditional Chinese medicine (TCM) formula particles, with traditional decoction for reference and the intervention of Magnoliae Officinalis Cortex in rats with ulcerative colitis (UC). First of all, the similarity of traditional Magnoliae Officinalis Cortex decoction and formula particles of different manufacturers was defined by using the IR fingerprint. The UC rat model was established and given Houpo formula particles of different doses and manufacturers, with the decoction for reference, in order to observe disease activity index (DAI), colon mucosa damage index (CMDI), pathologic changes, nitric oxide (NO), endothdin (ET), substance P, vasoactive intestinal peptide (VIP). Their intervention effects on UC rats were compared to study the difference between Sanjiu and Tianjiang Houpo formula particles, in order to demonstrate the feasibility of the pharmacodynamic evaluation method for Houpo formula particles. According to the results, Houpo formula particles showed similar pharmacodynamic actions with the traditional decoction. The pharmacodynamic comparison of Houpo formula particles of different manufacturers showed no statistical significance. The experiment showed that on the basis of the TCM compounds, a prescription dismantlement study was conducted to define target points of various drugs. The traditional decoction was selected for reference in the comparison of corresponding formula particles for their pharmacodynamic equivalence. This method could avoid controversies about single or combined boiling of formula particles, and give objective comments on the pharmacodynamic effect of the formula particles. The method is proved to be feasible. PMID:25039188

  5. Observational Study of Ion Diffusion Region tailward of the Cusp: Polar and Cluster Observations in 1998-2008

    NASA Astrophysics Data System (ADS)

    Muzamil, F. M.; Farrugia, C. J.; Torbert, R. B.; Argall, M. R.; Wang, S.

    2015-12-01

    Asymmetries in plasma density and the presence of a guide field significantly alter the structure of the ion diffusion region (IDR) in symmetric, collisionless reconnection. These features have been shown by numerical simulations under moderate density asymmetries (~10), and theoretical analyses. However, very few studies have addressed these issues with in-situ observations. We have compiled a collection of Cluster and Polar crossings of the high-latitude magnetopause poleward of the cusp under northward interplanetary magnetic field in the years 1998-2008 when signatures of reconnection inside the IDR are observed. They encompass a wide range of density asymmetries (~10 to 1000), magnetic field asymmetries (~0.2 to 0.9), and guide fields (~10 to ~60 %). In this dedicated observational study, we target the following topics: (1) The alteration of the structure of the IDR -- i.e., its width, the non-colocation of stagnation and X-lines, jet outflow speed, and biasing of the reconnection outflow jet toward the magnetosphere -- as a function of increasing density asymmetry, and (2) the diamagnetic drift of the X-line. Further, focusing on IDR crossings during plasma flow reversals and/or near-simultaneous crossings on either side of the X-line by two spacecraft under steady ambient conditions, we report on the contrast in the Hall fields and the plasma behavior on the sunward versus the tailward sides of the X-line in its dependence on the strength of the guide field.

  6. Demystifying the Enigma of Smoking – An Observational Comparative Study on Tobacco Smoking

    PubMed Central

    Nallakunta, Rajesh; Reddy, Sudhakara Reddy; Chennoju, Sai Kiran

    2016-01-01

    Introduction Smoking is a hazardous habit which causes definite changes in the oral cavity, consequently there exist changes in the mucosa when subjected to smoking. Palatal mucosa is first to be affected. The present study determines the palatal status in reverse smokers and conventional smokers. Aim To study and compare the clinical, cytological and histopathological changes in palatal mucosa among reverse and conventional smokers. Materials and Methods Study sample was categorized into two groups. Group 1 comprised of 20 subjects with the habit of reverse smoking and Group 2 comprised of 20 subjects with the habit of conventional smoking. Initially, clinical appearance of the palatal mucosa was recorded, followed by a cytological smear and biopsy of the involved area among all the subjects. The findings were studied clinically, the specimens were analysed cytologically and histopathologically, and compared among the two groups. Results The severity of clinical changes of the palatal mucosa among reverse smokers was statistically significant when compared to those of conventional smokers. There was no statistically significant difference observed in cytological staging between the groups with a p-value of 0.35. The histopathological changes in both the groups showed a significant difference with a p-value of 0.02. A significant positive correlation was observed between the clinical appearance, and cytological, histopathological changes. Conclusion Profound clinically aggressive changes were observed in group I compared to group II. Severity of dysplastic changes have been detected in few subjects through histopathological examination irrespective of no prominent clinical and cytological changes observed among the two groups. PMID:27190962

  7. Empathy levels among first year Malaysian medical students: an observational study

    PubMed Central

    Williams, Brett; Sadasivan, Sivalal; Kadirvelu, Amudha; Olaussen, Alexander

    2014-01-01

    Background The literature indicates that medical practitioners experience declining empathy levels in clinical practice. This highlights the need to educate medical students about empathy as an attribute early in the academic curriculum. The objective of this study was to evaluate year one students’ self-reported empathy levels following a 2-hour empathy workshop at a large medical school in Malaysia. Methods Changes in empathy scores were examined using a paired repeated-measures t-test in this prospective before and after study. Results Analyzing the matched data, there was a statistically significant difference and moderate effect size between mean empathy scores before and 5 weeks after the workshop (112.08±10.67 versus 117.93±13.13, P<0.0001, d=0.48) using the Jefferson Scale Physician Empathy (Student Version). Conclusion The results of this observational study indicate improved mean self-reported empathy scores following an empathy workshop. PMID:24876799

  8. Observational descriptive study of cutaneous manifestations in patients from Mato Grosso with viral chronic hepatitis*

    PubMed Central

    Rostey, Renato Roberto Liberato; Souto, Francisco José Dutra

    2015-01-01

    BACKGROUND Extrahepatic manifestations are seen in association with chronic infection by hepatitis B or C virus including cutaneous disorders. The frequency of these findings seems to vary among different places and reports. There is a lack of information about this issue in Brazil. OBJECTIVES To estimate the prevalence of cutaneous findings affecting HBV or HCV carriers from a reference outpatient unit in Mato Grosso. METHODS A cross-sectional observational study. RESULTS 108 patients were studied. 88.9% presented some cutaneous findings but must of them were nonrelated to chronic viral infection. Four patients had cutaneous or autoimmune syndromes that may be HBV or HCV related. CONCLUSION In our study we found no statistical association between viral hepatitis and skin diseases. PMID:26734863

  9. An observer study methodology for evaluating detection of motion abnormalities in gated myocardial perfusion SPECT.

    PubMed

    Lalush, David S; Jatko, Megan K; Segars, W Paul

    2005-03-01

    To address the task of detecting nonischemic motion abnormalities from animated displays of gated myocardial perfusion single photon emission computed tomography data, we performed an observer study to evaluate the difference in detection performance between gating to 8 and 16 frames. Images were created from the NCAT mathematical phantom with a realistic heart simulating hypokinetic motion in the left lateral wall. Realistic noise-free projection data were simulated for both normal and defective hearts to obtain 16 frames for the cardiac cycle. Poisson noise was then simulated for each frame to create 50 realizations of each heart, All datasets were processed in two ways: reconstructed as a 16-frame set, and collapsed to 8 frames and reconstructed. Ten observers viewed the cardiac images animated with a realistic real-time frame rate. Observers trained on 100 images and tested on 100 images, rating their confidence on the presence of a motion defect on a continuous scale. None of the observers showed a significant difference in performance between the two gating methods. The 95% confidence interval on the difference in areas under the ROC curve (Az8 - Az16) was -0.029-0.085. Our test did not find a significant difference in detection performance between 8-frame gating and 16-frame gating. We conclude that, for the task of detecting abnormal motion, increasing the number of gated frames from 8 to 16 offers no apparent advantage.

  10. Self-reported and observed seat belt use--A case study: Bosnia and Herzegovina.

    PubMed

    Lipovac, Krsto; Tešić, Milan; Marić, Bojan; Đerić, Miroslav

    2015-11-01

    The issue of seat belt use in middle- and low-income countries is strongly evident and has as a result higher rates of fatalities and seriously injured on the roads. The first systematic field research of the seat belt use while driving was carried out in Bosnia and Herzegovina, in 2011-2012. Research methodology consisted of two mutually conditioned parts (observation and self-reported behavior). Specific features of the methodology used are in the relationship between the observed and interviewed drivers which enabled the analysis of their observed and self-reported behavior while driving. The logistic regression method was used in this work to make the analysis of the influence of personal human characteristics (gender, age, education, exposure) and vehicles' characteristics (age) on the observed and self-reported driving behavior, from the point of view of seat belt use while driving. The influence of the listed factors on driving behavior, depending on road type (urban or rural), was given special attention in the analysis. The paper shows that certain factors do not have the same impact on driving behavior, in various conditions. Based on results from this study, it will be possible to define certain critical groups of road users and the way in which they must be addressed in order to increase the seat belt wearing rate. PMID:26320737

  11. A Mixed Methods Sampling Methodology for a Multisite Case Study

    ERIC Educational Resources Information Center

    Sharp, Julia L.; Mobley, Catherine; Hammond, Cathy; Withington, Cairen; Drew, Sam; Stringfield, Sam; Stipanovic, Natalie

    2012-01-01

    The flexibility of mixed methods research strategies makes such approaches especially suitable for multisite case studies. Yet the utilization of mixed methods to select sites for these studies is rarely reported. The authors describe their pragmatic mixed methods approach to select a sample for their multisite mixed methods case study of a…

  12. A new method of producing casts for anatomical studies.

    PubMed

    De Sordi, Nadia; Bombardi, Cristiano; Chiocchetti, Roberto; Clavenzani, Paolo; Trerè, Claudio; Canova, Marco; Grandis, Annamaria

    2014-09-01

    The objective of the present study was to verify if polyurethane foam is a suitable material to make accurate casts of vessels and viscera, and to develop a method based on its use for anatomical studies. This new technique has been tested primarily on the lungs of different animals, but also on the renal, intestinal and equine digital vessels. It consisted of three steps: specimen preparation, injection of the foam and corrosion of the cast. All structures injected with foam were properly filled. The bronchial tree and the vessels could be observed up to their finer branches. The method is inexpensive, simple and requires no special equipment. The pre-casting procedure does not require perfusion of the specimens with formalin, or prolonged flushing with carbon dioxide gas or air for drying. The polyurethane foam does not need a catalyst. It is simply diluted with acetone, which does not cause shrinkage of the cast due to evaporation during hardening. The foam naturally expands into the cavities without high pressure of the inoculum, and hardens in just 2 or 3 h at room temperature. Only two drawbacks were observed. The first is the fact that multiple injections cannot be made in the same cavity since the foam solidifies quickly; the second is the slight brittleness of the cast, due to the low elasticity of polyurethane foam. In conclusion, polyurethane foam was a suitable material for producing accurate casts of vessels and viscera. PMID:24788383

  13. Peak Bagging of red giant stars observed by Kepler: first results with a new method based on Bayesian nested sampling

    NASA Astrophysics Data System (ADS)

    Corsaro, Enrico; De Ridder, Joris

    2015-09-01

    The peak bagging analysis, namely the fitting and identification of single oscillation modes in stars' power spectra, coupled to the very high-quality light curves of red giant stars observed by Kepler, can play a crucial role for studying stellar oscillations of different flavor with an unprecedented level of detail. A thorough study of stellar oscillations would thus allow for deeper testing of stellar structure models and new insights in stellar evolution theory. However, peak bagging inferences are in general very challenging problems due to the large number of observed oscillation modes, hence of free parameters that can be involved in the fitting models. Efficiency and robustness in performing the analysis is what may be needed to proceed further. For this purpose, we developed a new code implementing the Nested Sampling Monte Carlo (NSMC) algorithm, a powerful statistical method well suited for Bayesian analyses of complex problems. In this talk we show the peak bagging of a sample of high signal-to-noise red giant stars by exploiting recent Kepler datasets and a new criterion for the detection of an oscillation mode based on the computation of the Bayesian evidence. Preliminary results for frequencies and lifetimes for single oscillation modes, together with acoustic glitches, are therefore presented.

  14. A systematic review of observational studies on oxidative/nitrosative stress involvement in dengue pathogenesis

    PubMed Central

    Pinzón, Hernando Samuel; Alvis-Guzman, Nelson

    2015-01-01

    Objective: Our objective was to systematically review the published observational research related to the role of oxidative-nitrosative stress in pathogenesis of dengue. Methods: We searched electronic databases (PubMed, EMBASE, The COCHRANE library, ScienceDirect, Scopus, SciELO, LILACS via Virtual Health Library, Google Scholar) using the term: dengue, dengue virus, severe dengue, oxidative stress, nitrosative stress, antioxidants, oxidants, free radicals, oxidized lipid products, lipid peroxides, nitric oxide, and nitric oxide synthase. Articles were selected for review by title and abstract excluding letter, review, in vivo and in vitro studies, and duplicates studies. Selected articles were reviewed for study design, original purposes, sample size, main outcomes, methods, and oxidative-nitrosative stress markers values. Results: In total, 4,331 non-duplicates articles were identified from electronic databases searches, of which 16 were eligible for full text searching. Data from the observational studies originate from Asian countries (50%; 8/16), South American countries (31.2%; 5/16), and Central America and the Caribbean countries (18.8%; 3/16). Case-control study was the type of design most common in researches reviewed. The 1997 World Health Organization (WHO) dengue case classification criteria were used in all studies included in this review. Conclusions: Based on published data found in peer-reviewed literature, oxidative and nitrosative stress are demonstrated by changes in plasma levels of nitric oxide, antioxidants, lipid peroxidation and protein oxidation markers in patients with dengue infection. Additionally, elevated serum protein carbonyls and malondialdehyde levels appear to be associated with dengue disease severity. PMID:26600629

  15. Study Methods to Standardize Thermography NDE

    NASA Technical Reports Server (NTRS)

    Walker, James L.; Workman, Gary L.

    1998-01-01

    The purpose of this work is to develop thermographic inspection methods and standards for use in evaluating structural composites and aerospace hardware. Qualification techniques and calibration methods are investigated to standardize the thermographic method for use in the field. Along with the inspections of test standards structural hardware, support hardware is designed and fabricated to aid in the thermographic process. Also, a standard operating procedure is developed for performing inspections with the Bales Thermal Image Processor (TIP). Inspections are performed on a broad range of structural composites. These materials include graphite/epoxies, graphite/cyanide-ester, graphite/silicon-carbide, graphite phenolic and Kevlar/epoxy. Also metal honeycomb (titanium and aluminum faceplates over an aluminum honeycomb core) structures are investigated. Various structural shapes are investigated and the thickness of the structures vary from as few as 3 plies to as many as 80 plies. Special emphasis is placed on characterizing defects in attachment holes and bondlines, in addition to those resulting from impact damage and the inclusion of foreign matter. Image processing through statistical analysis and digital filtering is investigated to enhance the quality and quantify the NDE thermal images when necessary.

  16. Study Methods to Standardize Thermography NDE

    NASA Technical Reports Server (NTRS)

    Walker, James L.; Workman, Gary L.

    1998-01-01

    The purpose of this work is to develop thermographic inspection methods and standards for use in evaluating structural composites and aerospace hardware. Qualification techniques and calibration methods are investigated to standardize the thermographic method for use in the field. Along with the inspections of test standards structural hardware, support hardware is designed and fabricated to aid in the thermographic process. Also, a standard operating procedure is developed for performing inspections with the Bales Thermal Image Processor (TIP). Inspections are performed on a broad range of structural composites. These materials include various graphite/epoxies, graphite/cyanide-ester, graphite/silicon-carbide, graphite phenolic and Keviar/epoxy. Also metal honeycomb (titanium and aluminum faceplates over an aluminum honeycomb core) structures are investigated. Various structural shapes are investigated and the thickness of the structures vary from as few as 3 plies to as many as 80 plies. Special emphasis is placed on characterizing defects in attachment holes and bondlines, in addition to those resulting from impact damage and the inclusion of foreign matter. Image processing through statistical analysis and digital filtering is investigated to enhance the quality and quantify the NDE thermal images when necessary.

  17. Feeling respected: a Parse method study.

    PubMed

    Parse, Rosemarie Rizzo

    2006-01-01

    This article reports a Parse research study on feeling respected with 10 participants. The finding of this study is the structure: The lived experience of feeling respected is fortifying assuredness amid potential disregard emerging with the fulfilling delight of prized alliances. The structure is discussed in light of the human becoming school of thought and related literature.

  18. A New Standard Installation Method of the Offline Seismic Observation Station in Heavy Snowfall Area of Tohoku Region

    NASA Astrophysics Data System (ADS)

    Hirahara, S.; Nakayama, T.; Hori, S.; Sato, T.; Chiba, Y.; Okada, T.; Matsuzawa, T.

    2015-12-01

    Soon after the 2011 Tohoku earthquake, seismic activity of Tohoku region, NE Japan is induced in the inland area of Akita prefecture and the border area between Fukushima and Yamagata prefectures. We plan to install a total of 80 offline seismic observation stations in these areas for studying the effect of megathrust earthquake on the activities of inland earthquakes. In our project, maintenance will be held twice-a-year for 4 years from 2015 by using 2.0Hz short-period 3-component seismometer, KVS-300 and ultra-low-power data logger, EDR-X7000 (DC12V 0.08W power supply). We installed seismometer on the rock surface or the slope of the natural ground at the possible sites confirmed with low noise level to obtain distinct seismic waveform data. We report an improvement in installation method of the offline seismic observation station in the heavy snowfall area of Tohoku region based on the retrieved data. In the conventional method, seismometer was installed in the hand-dug hole of a slope in case it is not waterproof. Data logger and battery were installed in the box container on the ground surface, and then, GPS antenna was installed on the pole fixed by stepladder. There are risks of the inclination of seismometer and the damage of equipment in heavy snowfall area. In the new method, seismometer is installed in the robust concrete box on the buried basement consists of precast concrete mass to keep its horizontality. Data logger, battery, and GPS antenna are installed on a high place by using a single pole with anchor bolt and a pole mount cabinet to enhance their safety. As a result, total costs of installation are kept down because most of the equipment is reusable. Furthermore, an environmental burden of waste products is reduced.

  19. A method of observing cherenkov light from extensive air shower at Yakutsk EAS array

    NASA Astrophysics Data System (ADS)

    Timofeev, Lev; Anatoly, Ivanov

    2016-07-01

    Proposed a new method for measuring the cherenkov light from the extensive air shower (EAS) of cosmic rays (CR), which allows to determine not only the primary particle energy and angle of arrival, but also the parameters of the shower in the atmosphere - the maximum depth and "age". For measurements Cherenkov light produced by EAS is proposed to use a ground network of wide-angle telescopes which are separated from each other by a distance 100-300 m depending on the total number of telescopes operating in the coincidence signals, acting autonomously, or includes a detector of the charged components, radio waves, etc. as part of EAS. In a results such array could developed, energy measurement and CR angle of arrival data on the depth of the maximum and the associated mass of the primary particle generating by EAS. This is particularly important in the study of galactic cosmic ray in E> 10^14 eV, where currently there are no direct measurements of the maximum depth of the EAS.

  20. Generalizability and Decision Studies to Inform Observational and Experimental Research in Classroom Settings

    ERIC Educational Resources Information Center

    Bottema-Beutel, Kristen; Lloyd, Blair; Carter, Erik W.; Asmus, Jennifer M.

    2014-01-01

    Attaining reliable estimates of observational measures can be challenging in school and classroom settings, as behavior can be influenced by multiple contextual factors. Generalizability (G) studies can enable researchers to estimate the reliability of observational data, and decision (D) studies can inform how many observation sessions are…

  1. Functional Outcome Following Arthroscopic ACL Reconstruction with Rigid Fix: A Retrospective Observational Study

    PubMed Central

    Shervegar, Satish; Nagaraj, Prashanth; Grover, Amit; DJ, Niranthara Ganesh; Ravoof, Abdul

    2015-01-01

    Background: No uniform consensus exists to decide type of fixation for arthroscopic anterior cruciate ligament reconstruction. Hypothsis: There is similar functional outcome after rigid fix compared to other methods of fixation which has been published. Study design: Retrospective observational study. Methods: A total of 50 patients underwent arthroscopic anterior cruciate ligament reconstruction with hamstring tendons using femoral Rigid fix cross-pin and interference screw tibial fixation. The evaluation methods were clinical examination, IKDC scores, Lysholm and pre injury and post reconstruction Tegner score. Patients were followed up from minimum of 6 months to 4 year seven months. Results: C In our study of sample size 50 we found that mean age of patients was 30.8 Years with male preponderance. Mean post operative IKDC and Lysholm score has been 75.6 and 84.4 respectively. Mean Tegner pre-injury score and post reconstruction score has been 5.4 and 4.26. Box plot comparison of pre injury and post operativeTegner score reveals a statistically significant difference with respect to paired t test P<0.001. Conclusions: Arthroscopic anterior cruciate ligament reconstruction with femoral rigid fix cross pins and tibial interference screws results in comparable short term to midterm functional results compared to other types of fixation PMID:26550591

  2. IPS observations at 140 MHz to study solar wind speeds and density fluctuations by MEXART

    NASA Astrophysics Data System (ADS)

    Chang, Oyuki; Gonzalez-Esparza, J. A.; Mejia-Ambriz, J.

    2016-03-01

    The interplanetary scintillation (IPS) technique is a remote-sensing method for monitoring the inner heliosphere. These observations supply information on solar wind conditions covering heliocentric ranges that no other technique can provide. The Mexican Array Radio Telescope (MEXART) is a single-station instrument operating at 140 MHz, fully dedicated to performing solar-wind studies employing the IPS technique. We present solar-wind parameters (scintillation indices and solar-wind speeds), using the initial measurements from this array of four IPS sources (3C273, 3C283, 3C286, 3C298) detected during October-December 2014. We report the transit of an IPS radio source (3C298), observed at 140 MHz, from weak- to strong-scattering regions at around 0.36 AU, and sky projection maps of solar wind conditions associated presumably with the passing of one or more Coronal Mass Ejections (CMEs). These results show the progress to operate the full array in the near future. The MEXART observations will complement the solar wind IPS studies using other frequencies, and the tracking of solar wind disturbances by other stations located at different longitudes. These solar wind measurements, provided in real time, can have space-weather forecasting applications.

  3. The Effects of Nutritional Juice Supplementation on the Extent of Climacteric Symptoms: An Observational Study

    PubMed Central

    Gresser, Ursula; Richartz, Barbara M.

    2016-01-01

    Objective. This study aims to evaluate the effect of daily dietary nutritional supplement on somatic, psychological, and urogenital symptoms in postmenopausal women. Material and Methods. In this study 28 healthy, symptomatic, peri- and postmenopausal women of 47–67 years of age were allocated to use the nutritional supplement JuicePLUS+®. Primary research parameters: Menopause Rating Scale (MRS) was used to assess menopausal symptoms at baseline and after 8 and 16 weeks of treatment. Secondary parameters: proliferation behaviour of vaginal smear was scored at baseline and after treatment. Results. Treatment with the supplement resulted in a reduction of somatic, psychological, and urogenital symptoms. The overall MRS score showed an average improvement of 44.01%. Most benefits were observed for the psychological symptoms irritability (60.55%) and physical and mental exhaustion (49.08%); modest effects were observed for hot flashes (44.86%) and sleeping problems (35.56%). There was a minor improvement in sexual problems; 6 women reported an increased libido. No statistically significant effect was found in vaginal dryness and proliferation behaviour of vaginal mucosa. No adverse effects were observed. Conclusion. Dietary nutritional supplement may constitute an effective alternative therapy to conventional alternative medicine for somatic, psychological, and sexual symptoms.

  4. The Effects of Nutritional Juice Supplementation on the Extent of Climacteric Symptoms: An Observational Study.

    PubMed

    Siebler, Stefanie I; Gresser, Ursula; Richartz, Barbara M

    2016-01-01

    Objective. This study aims to evaluate the effect of daily dietary nutritional supplement on somatic, psychological, and urogenital symptoms in postmenopausal women. Material and Methods. In this study 28 healthy, symptomatic, peri- and postmenopausal women of 47-67 years of age were allocated to use the nutritional supplement JuicePLUS+®. Primary research parameters: Menopause Rating Scale (MRS) was used to assess menopausal symptoms at baseline and after 8 and 16 weeks of treatment. Secondary parameters: proliferation behaviour of vaginal smear was scored at baseline and after treatment. Results. Treatment with the supplement resulted in a reduction of somatic, psychological, and urogenital symptoms. The overall MRS score showed an average improvement of 44.01%. Most benefits were observed for the psychological symptoms irritability (60.55%) and physical and mental exhaustion (49.08%); modest effects were observed for hot flashes (44.86%) and sleeping problems (35.56%). There was a minor improvement in sexual problems; 6 women reported an increased libido. No statistically significant effect was found in vaginal dryness and proliferation behaviour of vaginal mucosa. No adverse effects were observed. Conclusion. Dietary nutritional supplement may constitute an effective alternative therapy to conventional alternative medicine for somatic, psychological, and sexual symptoms. PMID:27668002

  5. The Effects of Nutritional Juice Supplementation on the Extent of Climacteric Symptoms: An Observational Study

    PubMed Central

    Gresser, Ursula; Richartz, Barbara M.

    2016-01-01

    Objective. This study aims to evaluate the effect of daily dietary nutritional supplement on somatic, psychological, and urogenital symptoms in postmenopausal women. Material and Methods. In this study 28 healthy, symptomatic, peri- and postmenopausal women of 47–67 years of age were allocated to use the nutritional supplement JuicePLUS+®. Primary research parameters: Menopause Rating Scale (MRS) was used to assess menopausal symptoms at baseline and after 8 and 16 weeks of treatment. Secondary parameters: proliferation behaviour of vaginal smear was scored at baseline and after treatment. Results. Treatment with the supplement resulted in a reduction of somatic, psychological, and urogenital symptoms. The overall MRS score showed an average improvement of 44.01%. Most benefits were observed for the psychological symptoms irritability (60.55%) and physical and mental exhaustion (49.08%); modest effects were observed for hot flashes (44.86%) and sleeping problems (35.56%). There was a minor improvement in sexual problems; 6 women reported an increased libido. No statistically significant effect was found in vaginal dryness and proliferation behaviour of vaginal mucosa. No adverse effects were observed. Conclusion. Dietary nutritional supplement may constitute an effective alternative therapy to conventional alternative medicine for somatic, psychological, and sexual symptoms. PMID:27668002

  6. Can we observe and study the Mediterranean outflow and meddies from satellite remote sensing?

    NASA Astrophysics Data System (ADS)

    Yan, Xiao-Hai; Jo, Young-Heon; Liu, W. Timothy; He, Ming-Xia

    2004-02-01

    Previous studies of the Mediterranean outflow and meddies (O&M) were limited by poor spatial and temporal resolution of the conventional observations. Little is known about meddies formation and transport, and the spatial and temporal variation of its trajectories. Generally speaking, most of the satellite observations are confined to the ocean's surface or its surface layer, while meddies were located, on an average, at a depth of 1000m. We developed a new remote sensing method to observe and study the O&M through unique approaches in satellite multi-sensor data integration analyses. Satellite altimeter, scatterometer, SST and XBT data were used to detect and calculate the trajectories and the relative transport of the O&M. We found that more northwestward meddies occurred in the spring and more southward meddies occurred in the fall than previously thought. Since the O&M play a significant role in carrying salty water from the Mediterranean into the Atlantic and contribute to the North Atlantic Deep Water (NADW) formation, such new knowledge about their trajectories, transport and life histories is important to understand their mixing and interaction with the North Atlantic water, adn hence, to lead to a better understanding of the global ocean circulation and the global change.

  7. Automated Parameter Studies Using a Cartesian Method

    NASA Technical Reports Server (NTRS)

    Murman, Scott M.; Aftosimis, Michael J.; Nemec, Marian

    2004-01-01

    Computational Fluid Dynamics (CFD) is now routinely used to analyze isolated points in a design space by performing steady-state computations at fixed flight conditions (Mach number, angle of attack, sideslip), for a fixed geometric configuration of interest. This "point analysis" provides detailed information about the flowfield, which aides an engineer in understanding, or correcting, a design. A point analysis is typically performed using high fidelity methods at a handful of critical design points, e.g. a cruise or landing configuration, or a sample of points along a flight trajectory.

  8. Lung cancer detection with digital chest tomosynthesis: first round results from the SOS observational study

    PubMed Central

    Viti, Andrea; Tavella, Chiara; Priotto, Roberto; Ghirardo, Donatella; Grosso, Maurizio; Terzi, Alberto

    2015-01-01

    Objective Baseline results of the Studio OSservazionale (SOS), observational study, a single-arm observational study of digital chest tomosynthesis for lung cancer detection in an at-risk population demonstrated a detection rate of lung cancer comparable to that of studies that used low dose CT scan (LDCT). We present the results of the first round. Methods Totally 1,703 out of 1,843 (92%) subjects who had a baseline digital chest tomosynthesis underwent a first round reevaluation after 1 year. Results At first round chest digital tomosynthesis, 13 (0.7%) subjects had an indeterminate nodule larger than 5 mm and underwent low-dose CT scan for nodule confirmation. PET/CT study was obtained in 10 (0.5%) subjects and 2 subjects had a low-dose CT follow up. Surgery, either video-assisted thoracoscopic or open surgery for indeterminate pulmonary nodules was performed in 10 (0.2%) subjects. A lung cancer was diagnosed and resected in five patients. The lung cancer detection rate at first round was 0.3% (5/1,703). Conclusions The detection rate of lung cancer at first round for tomosynthesis is comparable to rates reported for CT. In addition, results of first round digital chest tomosynthesis confirm chest tomosynthesis as a possible first-line lung cancer-screening tool. PMID:25992366

  9. Band-limited angular spectrum numerical propagation method with selective scaling of observation window size and sample number.

    PubMed

    Yu, Xiao; Xiahui, Tang; Yingxiong, Qin; Hao, Peng; Wei, Wang

    2012-11-01

    Band-limited angular spectrum (BLAS) methods can be used for simulating the diffractional propagation in the near field, the far field, the tilted system, and the nonparaxial system. However, it does not allow free sample interval on the output calculation window. In this paper, an improved BLAS method is proposed. This new algorithm permits a selective scaling of observation window size and sample number on the observation plane. The method is based on the linear convolution, which can be calculated by fast Fourier transform effectively.

  10. The Effects of Lesson Study on Classroom Observations and Perceptions of Lesson Effectiveness

    ERIC Educational Resources Information Center

    Myers, Julia

    2012-01-01

    This study examined the effects of lesson study on participants' classroom observations and perceptions of lesson effectiveness, by investigating the focus of their observations during a mathematics lesson and their ratings of the lesson's effectiveness, both preceding and subsequent to the lesson study experience. Prior to the lesson study,…

  11. Antithrombin III in patients admitted to intensive care units: a multicenter observational study

    PubMed Central

    Messori, Andrea; Vacca, Franca; Vaiani, Monica; Trippoli, Sabrina

    2002-01-01

    Introduction The administration of antithrombin III (ATIII) is useful in patients with congenital deficiency, but evidence for the other therapeutic indications of this drug is still uncertain. In Italy, the use of ATIII is very common in intensive care units (ICUs). For this reason we undertook an observational study to determine the pattern of use of ATIII in ICUs and to assess the outcome of patients given this treatment. Methods From 20 May to 20 July 2001 all consecutive patients admitted to ICUs in 20 Italian hospitals and treated with ATIII were enrolled. The following information was recorded from each patient: congenital deficiency, indication for use of ATIII, daily dose and duration of ATIII treatment, outcome of hospitalization (alive or dead). The outcome data of our observational study were compared with those reported in previously published randomized controlled trials (RCTs). Results Two hundred and sixteen patients were enrolled in the study. The clinical indications for using ATIII were sepsis (25.9%), disseminated intravascular coagulation (23.1%), and other clinical conditions (46.8%). At the end of the study, 65.3% of the patients were alive, 24.5% died and 10.2% were still in the hospital. Among the patients with sepsis (n = 56), 19 died during the observation period (33.9%; 95% confidence interval 22.1–47.5%). Discussion Our study described the pattern of use of ATIII in Italian hospitals and provided information on the outcome of the subgroup treated with sepsis. A meta-analysis of current data from RCTs, together with our findings, indicates that there is no sound basis for using this drug in ICU patients with sepsis. PMID:12398786

  12. A method for direct variational data assimilation from various observing systems

    NASA Astrophysics Data System (ADS)

    Penenko, Vladimir V.

    2015-11-01

    A new method for the joint use of mathematical models and heterogeneous data from various monitoring systems for ground and space based assets, including the sequence of images, is presented. The method is based on variational principles with weak constraints. The algorithm for its implementation allows us to use images in the problems of prediction and reconstruction of multidimensional fields of the state functions.

  13. Causal inference methods to study nonrandomized, preexisting development interventions.

    PubMed

    Arnold, Benjamin F; Khush, Ranjiv S; Ramaswamy, Padmavathi; London, Alicia G; Rajkumar, Paramasivan; Ramaprabha, Prabhakar; Durairaj, Natesan; Hubbard, Alan E; Balakrishnan, Kalpana; Colford, John M

    2010-12-28

    Empirical measurement of interventions to address significant global health and development problems is necessary to ensure that resources are applied appropriately. Such intervention programs are often deployed at the group or community level. The gold standard design to measure the effectiveness of community-level interventions is the community-randomized trial, but the conditions of these trials often make it difficult to assess their external validity and sustainability. The sheer number of community interventions, relative to randomized studies, speaks to a need for rigorous observational methods to measure their impact. In this article, we use the potential outcomes model for causal inference to motivate a matched cohort design to study the impact and sustainability of nonrandomized, preexisting interventions. We illustrate the method using a sanitation mobilization, water supply, and hygiene intervention in rural India. In a matched sample of 25 villages, we enrolled 1,284 children <5 y old and measured outcomes over 12 mo. Although we found a 33 percentage point difference in new toilet construction [95% confidence interval (CI) = 28%, 39%], we found no impacts on height-for-age Z scores (adjusted difference = 0.01, 95% CI = -0.15, 0.19) or diarrhea (adjusted longitudinal prevalence difference = 0.003, 95% CI = -0.001, 0.008) among children <5 y old. This study demonstrates that matched cohort designs can estimate impacts from nonrandomized, preexisting interventions that are used widely in development efforts. Interpreting the impacts as causal, however, requires stronger assumptions than prospective, randomized studies.

  14. Study methods for disinfection water for injection

    NASA Astrophysics Data System (ADS)

    Grishkanich, Alexander; Zhevlakov, Alexander; Kascheev, Sergey; Polyakov, Vladimir; Sidorov, Igor; Ruzankina, Julia; Yakovlev, Alexey; Mak, Andrey

    2016-04-01

    Experimental results presented in this study tends to explore viruses in the water for their further decontamination under the influence of laser radiation (λ=220-390 nm). Conducted a series of experiments to study the dependence of water quality from the effects of laser radiation. Correlation between degree of survival of viruses and power density. The results showed that all the analyzed samples of water is clearing from bacteria to 98%. Preliminary tests of the prototype laboratory system UFOVI has opened up new opportunities for water sterilizing.

  15. Paracetamol: not as safe as we thought? A systematic literature review of observational studies

    PubMed Central

    Roberts, Emmert; Delgado Nunes, Vanessa; Buckner, Sara; Latchem, Susan; Constanti, Margaret; Miller, Paul; Doherty, Michael; Zhang, Weiya; Birrell, Fraser; Porcheret, Mark; Dziedzic, Krysia; Bernstein, Ian; Wise, Elspeth; Conaghan, Philip G

    2016-01-01

    Objectives We conducted a systematic literature review to assess the adverse event (AE) profile of paracetamol. Methods We searched Medline and Embase from database inception to 1 May 2013. We screened for observational studies in English, which reported mortality, cardiovascular, gastrointestinal (GI) or renal AEs in the general adult population at standard analgesic doses of paracetamol. Study quality was assessed using Grading of Recommendations Assessment, Development and Evaluation. Pooled or adjusted summary statistics were presented for each outcome. Results Of 1888 studies retrieved, 8 met inclusion criteria, and all were cohort studies. Comparing paracetamol use versus no use, of two studies reporting mortality one showed a dose–response and reported an increased relative rate of mortality from 0.95 (0.92 to 0.98) to 1.63 (1.58 to 1.68). Of four studies reporting cardiovascular AEs, all showed a dose–response with one reporting an increased risk ratio of all cardiovascular AEs from 1.19 (0.81 to 1.75) to 1.68 (1.10 to 2.57). One study reporting GI AEs reported a dose–response with increased relative rate of GI AEs or bleeds from 1.11 (1.04 to 1.18) to 1.49 (1.34 to 1.66). Of four studies reporting renal AEs, three reported a dose–response with one reporting an increasing OR of ≥30% decrease in estimated glomerular filtration rate from 1.40 (0.79 to 2.48) to 2.19 (1.4 to 3.43). Discussion Given the observational nature of the data, channelling bias may have had an important impact. However, the dose–response seen for most endpoints suggests a considerable degree of paracetamol toxicity especially at the upper end of standard analgesic doses. PMID:25732175

  16. Methods for Studying Ciliary Import Mechanisms.

    PubMed

    Takao, Daisuke; Verhey, Kristen J

    2016-01-01

    Cilia and flagella are microtubule-based organelles that play important roles in human health by contributing to cellular motility as well as sensing and responding to environmental cues. Defects in cilia formation and function cause a broad class of human genetic diseases called ciliopathies. To carry out their specialized functions, cilia contain a unique complement of proteins that must be imported into the ciliary compartment. In this chapter, we describe methods to measure the permeability barrier of the ciliary gate by microinjection of fluorescent proteins and dextrans of different sizes into ciliated cells. We also describe a fluorescence recovery after photobleaching (FRAP) assay to measure the entry of ciliary proteins into the ciliary compartment. These assays can be used to determine the molecular mechanisms that regulate the formation and function of cilia in mammalian cells. PMID:27514912

  17. The Hydrological Cycle on the Tibetan Plateau - Observed by Multisensoral Remote Sensing Methods

    NASA Astrophysics Data System (ADS)

    Hochschild, V.

    2015-12-01

    Climate change and its potential effects are of global interest. Lake ice and snow coverage act as effective indicators of climate change due to their sensitivity to climate elements (like air temperature in the case of the lake ice), and can be observed on a large-scale with the help of remote sensing. The lakes on the Tibetan Plateau are important indicators for the development of the high mountain ecosystems facing the impacts of future climatic warming on runoff from snow and ice. Many of these Tibetan lakes are remote and hard to access, so multi-sensoral remote sensing is a valuable tool to generate hydrological relevant information as modeling input (land cover, soil moisture, trends in mountain lake ice cover, etc.) or validation base (lake level changes) . Tibetan lakes are remote and hard to access. For the monitoring of the lake ice, the first and the last day of the partial ice cover and the period of total ice cover are defined on the basis of temporal high temporal resolution MODIS data. The larger lakes were compared and put into regional groups in order to delineate and define different local trends. For obtaining a better spatial resolution for the calculation of the ice covered area, additional medium and high resolution optical and microwave data (ERS-1, ERS-2, ENVISAT A-SAR, LANDSAT, Kompsat-2, RapidEye) were considered, which at the same time, have a smaller temporal resolution. By means of correlation of the different data, the respective advantages of each data type are merged and were then exploited for the exaction of the iced surface and calculation of its area extent calculation. The study is enhanced by the use of passive microwave data (SSM/I, AMSR-E) which provides very high temporal resolution information as validation input. Simultaneously TerraSAR-X ScanSAR data was analysed for the whole winter period 2011 (December until April) in order to derive the spatial distribution of different ice types. The snow cover is an important

  18. Galactic cold cores. VII. Filament formation and evolution: Methods and observational constraints

    NASA Astrophysics Data System (ADS)

    Rivera-Ingraham, A.; Ristorcelli, I.; Juvela, M.; Montillaud, J.; Men'shchikov, A.; Malinen, J.; Pelkonen, V.-M.; Marston, A.; Martin, P. G.; Pagani, L.; Paladini, R.; Paradis, D.; Ysard, N.; Ward-Thompson, D.; Bernard, J.-P.; Marshall, D. J.; Montier, L.; Tóth, L. V.

    2016-06-01

    Context. The association of filaments with protostellar objects has made these structures a priority target in star formation studies. However, little is known about the link between filament properties and their local environment. Aims: The datasets from the Herschel Galactic Cold cores key programme allow for a statistical study of filaments with a wide range of intrinsic and environmental characteristics. Characterisation of this sample can therefore be used to identify key physical parameters and quantify the role of the environment in the formation of supercritical filaments. These results are necessary to constrain theoretical models of filament formation and evolution. Methods: Filaments were extracted from fields at distance D< 500 pc with the getfilaments algorithm and characterised according to their column density profiles and intrinsic properties. Each profile was fitted with a beam-convolved Plummer-like function, and the filament structure was quantified based on the relative contributions from the filament "core", represented by a Gaussian, and "wing" component, dominated by the power-law behaviour of the Plummer-like function. These filament parameters were examined for populations associated with different background levels. Results: Filaments increase their core (Mline,core) and wing (Mline,wing) contributions while increasing their total linear mass density (Mline,tot). Both components appear to be linked to the local environment, with filaments in higher backgrounds having systematically more massive Mline,core and Mline,wing. This dependence on the environment supports an accretion-based model of filament evolution in the local neighbourhood (D ≤ 500 pc). Structures located in the highest backgrounds develop the highest central AV, Mline,core, and Mline,wing as Mline,tot increases with time, favoured by the local availability of material and the enhanced gravitational potential. Our results indicate that filaments acquiring a significantly

  19. An inversion method for retrieving soil moisture information from satellite altimetry observations

    NASA Astrophysics Data System (ADS)

    Uebbing, Bernd; Forootan, Ehsan; Kusche, Jürgen; Braakmann-Folgmann, Anne

    2016-04-01

    Soil moisture represents an important component of the terrestrial water cycle that controls., evapotranspiration and vegetation growth. Consequently, knowledge on soil moisture variability is essential to understand the interactions between land and atmosphere. Yet, terrestrial measurements are sparse and their information content is limited due to the large spatial variability of soil moisture. Therefore, over the last two decades, several active and passive radar and satellite missions such as ERS/SCAT, AMSR, SMOS or SMAP have been providing backscatter information that can be used to estimate surface conditions including soil moisture which is proportional to the dielectric constant of the upper (few cm) soil layers . Another source of soil moisture information are satellite radar altimeters, originally designed to measure sea surface height over the oceans. Measurements of Jason-1/2 (Ku- and C-Band) or Envisat (Ku- and S-Band) nadir radar backscatter provide high-resolution along-track information (~ 300m along-track resolution) on backscatter every ~10 days (Jason-1/2) or ~35 days (Envisat). Recent studies found good correlation between backscatter and soil moisture in upper layers, especially in arid and semi-arid regions, indicating the potential of satellite altimetry both to reconstruct and to monitor soil moisture variability. However, measuring soil moisture using altimetry has some drawbacks that include: (1) the noisy behavior of the altimetry-derived backscatter (due to e.g., existence of surface water in the radar foot-print), (2) the strong assumptions for converting altimetry backscatters to the soil moisture storage changes, and (3) the need for interpolating between the tracks. In this study, we suggest a new inversion framework that allows to retrieve soil moisture information from along-track Jason-2 and Envisat satellite altimetry data, and we test this scheme over the Australian arid and semi-arid regions. Our method consists of: (i

  20. Study of Supported Particle Catalysts by Electron Microscopy Methods.

    NASA Astrophysics Data System (ADS)

    Yao, Ming-Hui

    1994-01-01

    The imaging conditions for electron microscopy study of supported ultrafine particle catalysts were investigated both theoretically and experimentally. Particles supported on crystalline supports were simulated and compared in high resolution electron microscopy (HREM) plan view and profile view as a function of defocus, voltage, aperture size, and support thickness. Possibilities and techniques for improving particle visibility and resolution by selecting objective lens defocus, Fourier filtering, and profile imaging were discussed. Various microscopy techniques, including HREM, high resolution scanning electron microscopy (HRSEM) and high-angle annular dark field imaging (HAADF) were used in parallel to study supported metal particle catalysts, and relative merits and shortcomings of each method were evaluated. It was pointed out that HREM profile imaging was the most effective technique for direct observation of microstructure, especially the surface structure of supported particles, whereas HRSEM and HAADF, respectively, were preferred for characterizing the surface topology of catalyst supports and the size distribution of supported particles. The HREM profile imaging method was used to study the strong metal-support interaction on various temperature treated Pt/CeO_2, and Pt/TiO _2 samples. Ti oxide monolayer on Pt/TiO _2 was observed, and related to the suppressed hydrogenolysis activity observed after high temperature reduction. No similar surface layer was observed on Pt/CeO_2 after high temperature treatment even though the hydrogenolysis activity was also strongly suppressed. It is proposed that decoration model is the main mechanism responsible for the SMSI for Pt/TiO _2, while morphological change and epitaxial relation is the major cause for the metal-support interaction for Pt/CeO_2. As well as surface structure, surface area was also studied in detail. A procedure for measuring surface area of supported particles by TEM was developed and applied to

  1. Studying Distance Students: Methods, Findings, Actions

    ERIC Educational Resources Information Center

    Wahl, Diane; Avery, Beth; Henry, Lisa

    2013-01-01

    University of North Texas (UNT) Libraries began studying the library needs of distance learners in 2009 using a variety of approaches to explore and confirm these needs as well as obtain input into how to meet them. Approaches used to date include analysis of both quantitative and qualitative responses by online students to the LibQUAL+[R] surveys…

  2. Using Qualitative Methods to Study Friendships

    ERIC Educational Resources Information Center

    Bukowski, William; Lisboa, Carolina

    2005-01-01

    Basic concepts and procedures of qualitative analysis are discussed, especially as they relate to the study of the features, processes, and effects of friendships. The contributions of the previous chapters are presented according to theory and research on friendship as a developmental process.

  3. [Study methods of drugs in Alzheimer disease].

    PubMed

    Dubois, B; Stehlé, B; Lehner, J P; Derouesné, C; Bourin, M; Lamour, Y; Blin, O; Jourdain, G; Alperovitch, A

    1996-01-01

    The availability of new drugs for Alzheimer's disease, with different pharmacological profiles, leads to a redefinition the relevant methodology for developing drugs in this indication, including the inclusion/exclusion criteria, the duration of the studies, and therefore, the relevant guidelines. This was the purpose of the Giens Round-table devoted to the new methodology for drug development in Alzheimer disease.

  4. Solar EUV/FUV line polarimetry. I - Observational parameters and theoretical considerations. II - Instruments and methods

    NASA Technical Reports Server (NTRS)

    Fineschi, Silvano; Hoover, Richard B.; Fontenla, Juan M.; Walker, Arthur B. C., Jr.

    1991-01-01

    The paper discusses theoretical considerations and presents the observational parameters for the development of reflective FUV coronagraph/polarimeter and EUV imaging polarimeter instruments. New EUV/FUV polarimeter instrument concepts for solar research are described. One of these is a new coronagraph/polarimeter operating at 1215.6 A, which could observe the neutral hydrogen Ly-alpha line in the near solar corona and lead to the first direct measurements of both the strength and the direction of coronal magnetic fields. The other is a new multilayer EUV imaging polarimeter, operating at the wavelengths of strong He emission lines, which could observe impact polarization phenomena and provide information concerning the relative importance of thermal and nonthermal processes in solar flares.

  5. A Sparse Representation-Based Deployment Method for Optimizing the Observation Quality of Camera Networks

    PubMed Central

    Wang, Chang; Qi, Fei; Shi, Guangming; Wang, Xiaotian

    2013-01-01

    Deployment is a critical issue affecting the quality of service of camera networks. The deployment aims at adopting the least number of cameras to cover the whole scene, which may have obstacles to occlude the line of sight, with expected observation quality. This is generally formulated as a non-convex optimization problem, which is hard to solve in polynomial time. In this paper, we propose an efficient convex solution for deployment optimizing the observation quality based on a novel anisotropic sensing model of cameras, which provides a reliable measurement of the observation quality. The deployment is formulated as the selection of a subset of nodes from a redundant initial deployment with numerous cameras, which is an ℓ0 minimization problem. Then, we relax this non-convex optimization to a convex ℓ1 minimization employing the sparse representation. Therefore, the high quality deployment is efficiently obtained via convex optimization. Simulation results confirm the effectiveness of the proposed camera deployment algorithms. PMID:23989826

  6. Study of banana and coconut fibers Botanical composition, thermal degradation and textural observations.

    PubMed

    Bilba, Ketty; Arsene, Marie-Ange; Ouensanga, Alex

    2007-01-01

    Four fibers from banana-trees (leaf, trunk) and coconut-tree (husk, fabric) were examined before their incorporation in cementitious matrices, in order to prepare insulating material for construction. Their botanical compositions have been determined following a method described previously. Thermal degradation of these fibers were studied between 200 and 700 degrees C under nitrogen gas flow. Temperature of pyrolysis was the experimental parameter investigated. The solid residues obtained were analyzed by classical elemental analysis, Fourier Transform Infra Red (FTIR) spectroscopy and were observed by Scanning Electron Microscopy (SEM). This study has shown (1) the relation between botanical, chemical composition with both localization of fibers in the tree and type of tree; (2) the rapid and preferential decomposition of banana fibers with increasing temperature of pyrolysis and (3) the rough samples are made of hollow fibers.

  7. Evaluating outpatient transition clinics: a mixed-methods study protocol

    PubMed Central

    Sattoe, Jane N T; Peeters, Mariëlle A C; Hilberink, Sander R; Ista, Erwin; van Staa, AnneLoes

    2016-01-01

    Introduction To support young people in their transition to adulthood and transfer to adult care, a number of interventions have been developed. One particularly important intervention is the transition clinic (TC), where paediatric and adult providers collaborate. TCs are often advocated as best practices in transition care for young people with chronic conditions, but little is known about TC models and effects. The proposed study aims to gain insight into the added value of