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Sample records for based observational study

  1. Passive output feedback and observer based autopilots: A comparative study

    Directory of Open Access Journals (Sweden)

    Marit Paulsen

    1996-04-01

    Full Text Available Two methods for course-keeping of a ship are studied where no measurements of the yaw rate are available. The two methods are a passive output feedback controller and a controller-observer structure. A comparison with special attention to stability and wave filtering properties, is provided. Finally, a case study of a ship autopilot is included.

  2. The Reporting of Observational Research Studies in Dermatology Journals A Literature-Based Study

    NARCIS (Netherlands)

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

    2010-01-01

    Objective: To assess the quality of reporting in observational studies in dermatology. Data Sources: Five dermatology journals-the Archives of Dermatology, the British Journal of Dermatology, the Journal of the American Academy of Dermatology, the Journal of Investigative Dermatology, and Acta Derma

  3. Accretion dynamics and disk evolution in NGC 2264: a study based on the Corot photometric observations

    CERN Document Server

    Alencar, S H P; Guimaraes, M M; McGinnis, P T; Gameiro, J F; Bouvier, J; Aigrain, S; Flaccomio, E; Favata, F

    2010-01-01

    The young cluster NGC 2264 was observed with the Corot satellite for 23 days uninterruptedly in March 2008 with unprecedent photometric accuracy. We present here the first results of the analysis of the accreting population. We intended to look for possible light curve variability of the same nature as that observed in the classical T Tauri star AA Tau, which was attributed to a magnetically controlled inner disk warp, which is directly associated with the interaction between the stellar magnetic field and the inner disk region. We analysed the Corot light curves of 83 previously known classical T Tauri stars that belong to NGC 2264 and classified them according to their morphology. We also studied the Corot light curve morphology as a function of a Spitzer-based classification of the star-disk systems. The classification derived on the basis of the Corot light curve morphology agrees very well with the Spitzer IRAC-based classification of the systems. The percentage of AA Tau-like light curves decreases as t...

  4. Wind‐gust parametrizations at heights relevant for wind energy: a study based on mast observations

    DEFF Research Database (Denmark)

    Suomi, I.; Vihma, T.; Gryning, Sven-Erik;

    2013-01-01

    gustiness conditions were studied using observations from two coastal/archipelago weather masts in the Gulf of Finland (northern Europe) with observation heights between 30 and 143 m. Only moderate and strong wind cases were addressed. Both masts were located over relatively flat terrain but the local...

  5. LDA-SVM-based EGFR mutation model for NSCLC brain metastases: an observational study.

    Science.gov (United States)

    Hu, Nan; Wang, Ge; Wu, Yu-Hao; Chen, Shi-Feng; Liu, Guo-Dong; Chen, Chuan; Wang, Dong; He, Zhong-Shi; Yang, Xue-Qin; He, Yong; Xiao, Hua-Liang; Huang, Ding-De; Xiong, Kun-Lin; Wu, Yan; Huang, Ming; Yang, Zhen-Zhou

    2015-02-01

    Epidermal growth factor receptor (EGFR) activating mutations are a predictor of tyrosine kinase inhibitor effectiveness in the treatment of non-small-cell lung cancer (NSCLC). The objective of this study is to build a model for predicting the EGFR mutation status of brain metastasis in patients with NSCLC. Observation and model set-up. This study was conducted between January 2003 and December 2011 in 6 medical centers in Southwest China. The study included 31 NSCLC patients with brain metastases. Eligibility requirements were histological proof of NSCLC, as well as sufficient quantity of paraffin-embedded lung and brain metastases specimens for EGFR mutation detection. The linear discriminant analysis (LDA) method was used for analyzing the dimensional reduction of clinical features, and a support vector machine (SVM) algorithm was employed to generate an EGFR mutation model for NSCLC brain metastases. Training-testing-validation (3 : 1 : 1) processes were applied to find the best fit in 12 patients (validation test set) with NSCLC and brain metastases treated with a tyrosine kinase inhibitor and whole-brain radiotherapy. Primary and secondary outcome measures: EGFR mutation analysis in patients with NSCLC and brain metastases and the development of a LDA-SVM-based EGFR mutation model for NSCLC brain metastases patients. EGFR mutation discordance between the primary lung tumor and brain metastases was found in 5 patients. Using LDA, 13 clinical features were transformed into 9 characteristics, and 3 were selected as primary vectors. The EGFR mutation model constructed with SVM algorithms had an accuracy, sensitivity, and specificity for determining the mutation status of brain metastases of 0.879, 0.886, and 0.875, respectively. Furthermore, the replicability of our model was confirmed by testing 100 random combinations of input values. The LDA-SVM-based model developed in this study could predict the EGFR status of brain metastases in this small cohort of

  6. Land cover change impacts on surface ozone: an observation-based study

    Science.gov (United States)

    Zhang, Yi; Lin, Jintai

    2016-04-01

    Ozone air quality is a critical global environmental issue. Although it is clear that industrialization and urbanization has increased surface ozone through enhanced emissions of its precursors, much less is known about the role of changes in land cover and land use. Human activities have substantially altered the global land cover and land use through agriculture, urbanization, deforestation, and afforestation. Changes in Land cover and land use affect the ozone levels by altering soil emissions of nitrogen oxides (NOx), biogenic emissions of volatile organic compounds (VOCs), and dry deposition of ozone itself. This study performs a series of experiments with a chemical transport model based on satellite observation of land types to analyze the influences of changes in land cover/land use and their impact on surface ozone concentration. Our results indicate that land cover change explains 1-2 ppbv of summertime surface ozone increase in the Western United States and 1-6 ppbv of increase in Southern China between 2001 and 2012. This is largely driven by enhanced isoprene emissions and soil NOx emissions. It is also found that land cover change itself elevates summertime surface zone in Canadian coniferous forests by up to 4 ppbv mainly through substantial decreases in ozone dry deposition associated with increased vegetation density in a warmer climate.

  7. [Observational studies in the era of evidence based medicine: short review on their relevance, taxonomy and designs].

    Science.gov (United States)

    Fronteira, Ines

    2013-01-01

    In this review of the literature, we distinguish between experimental and observational studies, highlighting the importance that the later have gained in the era of evidence-based medicine. We further analyze the value of observational studies in light of experimental studies. We present a taxonomy for observational studies based on units of observation and measurement (cross-sectional or longitudinal). We distinguish between descriptive studies and analytical studies. Then, and given its specificity, we define and present a classification for ecological studies. We define and consider the advantages and disadvantages of cross-sectional, case control and cohort studies. We analyze the strength of the evidence given by each study design. We finished by examining what should guide the choice of a study design.

  8. The impact of European forests on cloud cover: an observation-based study

    Science.gov (United States)

    Teuling, Ryan; Melsen, Lieke; Vila-Guerau de Arellano, Jordi; van Heerwaarden, Chiel; Miralles, Diego; Taylor, Chris; Stegehuis, Annemiek; Fokke Meirink, Jan; Nabuurs, Gert-Jan

    2016-04-01

    The impact of temperate forests on their environment is still uncertain [1]. While forests generally have a lower albedo, the flux partitioning over forests and its relation to weather conditions is still poorly understood [2,3], complicating attempts to study impacts of forest cover on atmospheric conditions through modeling. Effects of land surface conditions on boundary-layer humidity and cloud formation can also be very non-linear [4]. Furthermore, the study of hydrological and climate impacts of temperate European forests is complicated because forests are strongly fragmented and often can be found on hilly terrain, making it impossible to attribute differences in for instance cloud cover or runoff directly to forest cover. Only few regions exist where forests can be found in absence of strong topography of a size large enough to result in near-equilibrium between the atmospheric boundary layer and local surface conditions. In this study, we analyse 10 years (2004-2013) of cloud cover observations from the Meteosat Second Generation satellite platform at a 15-minute temporal resolution. These observations come from a physically-based cloud product at the 6 km resolution [5], and a statistical cloud product based on the high-resolution visible imagery (1 km resolution). We focus on two regions in France where large forests are found which satisfy the following criteria: a) absence of strong topography, and b) presence of sharp contrast between forest and non-forest regions. Cloud occurrence is expressed by the fraction of the daytime that clouds are detected within a pixel. We find that in particular in summer and late summer, clouds are much more likely to occur over forest than over the surrounding non-forest land (difference in the order of 0.2). An opposite signal, but of much weaker magnitude, is found during springtime, when clouds are less likely to develop over forest. Difference in cloud occurrence is consistent with MODIS-derived differences in EVI

  9. Multiple Integrated Examinations: An Observational Study of Different Academic Curricula Based on a Business Administration Assessment

    Science.gov (United States)

    Ardolino, Piermatteo; Noventa, Stefano; Formicuzzi, Maddalena; Cubico, Serena; Favretto, Giuseppe

    2016-01-01

    An observational study has been carried out to analyse differences in performance between students of different undergraduate curricula in the same written business administration examination, focusing particularly on possible effects of "integrated" or "multi-modular" examinations, a recently widespread format in Italian…

  10. A mixed methods observational simulation-based study of interprofessional team communication

    DEFF Research Database (Denmark)

    Paltved, Charlotte; Nielsen, Kurt; Musaeus, Peter

    2013-01-01

    Interprofessional team communication has been identified as an important focus for safety in medical emergency care. However, in-depth insight into the complexity of team communication is limited. Video observational studies might fill a gap in terms of understanding the meaning of specific commu...

  11. On family-based genome-wide association studies with large pedigrees: observations and recommendations

    OpenAIRE

    Fardo, David W.; Zhang, Xue; Ding, Lili; He, Hua; Kurowski, Brad; Alexander, Eileen S.; Mersha, Tesfaye B.; Pilipenko, Valentina; Kottyan, Leah; Nandakumar, Kannabiran; Martin, Lisa

    2014-01-01

    Family based association studies are employed less often than case-control designs in the search for disease-predisposing genes. The optimal statistical genetic approach for complex pedigrees is unclear when evaluating both common and rare variants. We examined the empirical power and type I error rates of 2 common approaches, the measured genotype approach and family-based association testing, through simulations from a set of multigenerational pedigrees. Overall, these results suggest that ...

  12. Reluctance to screening colonoscopy in Arab Americans: a community based observational study.

    Science.gov (United States)

    Talaat, Nizar; Harb, Walid

    2013-08-01

    To explore compliance of Arab-Americans to colorectal cancer (CRC) screening and identify the barriers for non-compliance. An observational community based study. Arab-American Friday prayer attendees' ≥50 years in three mosques in Dearborn, MI volunteered. Demographics, health insurance status, screening history, availability of a primary care physician (PCP) and the ability to communicate in Arabic were inquired. The responses were compared using a student t test between respondents who have had CRC screening with colonoscopy and those who have not had any screening tests. A p value of 0.05 or lower was considered statistically significant. Total number surveyed was 130. Average age is 64 years. Males were 76 % (99) and females 24 % (31). More than 50 % were Lebanese and 28 % were from Yemen. Majority had health insurance (89 %), and 86 % had a primary care physician of which 79 % of them spoke Arabic. Half of the participants had colonoscopy mostly for screening purposes. Fifty-eight (45 %) participants did not have CRC screening. Majority of the females (72.4 %) had colonoscopy compared to 46.8 % of the males (p value = 0.016). The mean length of stay in the U.S was 39.16 years in the colonoscopy group compared to 30.77 years in the non-screening group (p value = 0.006). Participants without a PCP did not have CRC screening (77.8 %) (p value = 0.005). Participants with a non-Arabic speaking PCP had more colonoscopy rates (77.3 %) compared to those with an Arabic speaking PCP (50 %) (p value = 0.027). More Lebanese had colonoscopy (71.9 %) compared to 25.7 % of the surveyed Yemenis (p value = 0.00). Discomfort, unawareness about CRC screening, and nonrecommendation by PCP were reported barriers. Arab-Americans have lower screening colonoscopy rates. Unfamiliarity of the importance of screening is a principal issue. Having a non-arabic speaking PCP is beneficial. Better education to this population about the benefits and ease of

  13. Conversations between community-based neurologists and patients with epilepsy: results of an observational linguistic study.

    Science.gov (United States)

    Gilliam, Frank; Penovich, Patricia E; Eagan, Corey A; Stern, John M; Labiner, David M; Onofrey, Meaghan; Holmes, Gregory L; Mathis, Eileen; Cramer, Joyce

    2009-10-01

    An in-office linguistic study was conducted to assess neurologist-patient discussions of epilepsy. Naturally occurring interactions among 20 neurologists and 60 of their patients with epilepsy were recorded. Participants were interviewed separately postvisit. Transcripts were analyzed using sociolinguistic techniques. Of 59 patients taking antiepileptic drugs previsit, 44 (75%) discussed side effects with their neurologist. Side effect discussions were most often neurologist initiated. Postvisit, patients and neurologists often disagreed about which side effects were experienced. The presence of a caregiver (e.g., spouse) usually resulted in lengthier, more detailed discussions of side effects, without drastically increasing overall visit length. Discussions of mood- and behavior-related comorbidities occurred infrequently (14 of 60 visits); postvisit, neurologists stated that they felt that management of these conditions was outside their area of expertise. Communication gaps observed in discussions of epilepsy and its treatment warrant further exploration. Additional research is currently underway to assess the efficacy of a previsit assessment tool.

  14. A study on the integrity and authentication of weather observation data using Identity Based Encryption.

    Science.gov (United States)

    Seo, Jung Woo; Lee, Sang Jin

    2016-01-01

    Weather information provides a safe working environment by contributing to the economic activity of the nation, and plays role of the prevention of natural disasters, which can cause large scaled casualties and damage of property. Especially during times of war, weather information plays a more important role than strategy, tactics and information about trends of the enemy. Also, it plays an essential role for the taking off and landing of fighter jet and the sailing of warships. If weather information, which plays a major role in national security and economy, gets misused for cyber terrorism resulting false weather information, it could be a huge threat for national security and the economy. We propose a plan to safely transmit the measured value from meteorological sensors through a meteorological telecommunication network in order to guarantee the confidentiality and integrity of the data despite cyber-attacks. Also, such a plan allows one to produce reliable weather forecasts by performing mutual authentication through authentication devices. To make sure of this, one can apply an Identity Based Signature to ensure the integrity of measured data, and transmit the encrypted weather information with mutual authentication about the authentication devices. There are merits of this research: It is not necessary to manage authentication certificates unlike the Public Key Infrastructure methodology, and it provides a powerful security measure with the capability to be realized in a small scale computing environment, such as the meteorological observation system due to the low burden on managing keys.

  15. ACUTE UNDIFFERENTIATED FEBRILE ILLNESS AMONG ADULTS – A HOSPITAL BASED OBSERVATIONAL STUDY

    Directory of Open Access Journals (Sweden)

    Shivkumar

    2013-04-01

    Full Text Available ABSTRACT. BACKGROUND: Fever is a burning issue in the tropics and the mos t common cause of morbidity. Quite frequently this fever goes undi agnosed because of many reasons like the lack of diagnostic facilities, insufficient epidemi ological data available on causes of fever, and so on. This research study was aimed to find out the e tiology and clinical markers of Acute Undifferentiated Febrile Illness [AUFI] among the r ural population of Southern India. METHODOLOGY: This prospective, observational study was conducted at Government Villupuram Medical College and Hospital, a rural ter tiary care centre in Tamil Nadu, India. Consecutive hospitalised adult patients [>16 years] with AUFI[5-14 days fever] were enrolled into the study from August 2010 to February 2012 [1 8 months].Upon enrollment, detailed history was recorded, physical examination done and basic blood tests including biochemical examination, smear study for malaria, blood culture s and serology for the commonly encountered infections were done according to study protocol. The patients were followed up until clinical recovery and convalescence. The data were entered in MS excel and analyzed using Epi-info software 2008 version. RESULTS: A total of 403 patients were included in the study . The distribution of AUFI included Malaria 133[33%], Typhoid 83[20.59%], Dengue 42[10.4%], Leptospirosis 25[6.2%], and other causes 36[8.9%] and unknown cause 84[20.84%]. Malaria patients were significantly associated with jaundice , altered mentation, travel outside the district, elevated AST/ALT levels, thrombocytopenia and splenomegaly. Typhoid fever was associated with longer fever duration, abdominal pai n, coated tongue, relative bradycardia, normal platelet counts and low leucocyte count. Deng ue fever could be predicted by rash, pruritis, petechiae ,retro-orbital pain and low platele t counts. Leptospirosis patients showed significant association with conjunctival suffusion , muscle

  16. Acute hospital admissions among nursing home residents: a population-based observational study

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    Jamtvedt Gro

    2011-05-01

    Full Text Available Abstract Background Nursing home residents are prone to acute illness due to their high age, underlying illnesses and immobility. We examined the incidence of acute hospital admissions among nursing home residents versus the age-matched community dwelling population in a geographically defined area during a two years period. The hospital stays of the nursing home population are described according to diagnosis, length of stay and mortality. Similar studies have previously not been reported in Scandinavia. Methods The acute hospitalisations of the nursing home residents were identified through ambulance records. These were linked to hospital patient records for inclusion of demographics, diagnosis at discharge, length of stay and mortality. Incidence of hospitalisation was calculated based on patient-time at risk. Results The annual hospital admission incidence was 0.62 admissions per person-year among the nursing home residents and 0.26 among the community dwellers. In the nursing home population we found that dominant diagnoses were respiratory diseases, falls-related and circulatory diseases, accounting for 55% of the cases. The median length of stay was 3 days (interquartile range = 4. The in-hospital mortality rate was 16% and 30 day mortality after discharge 30%. Conclusion Acute hospital admission rate among nursing home residents was high in this Scandinavian setting. The pattern of diagnoses causing the admissions appears to be consistent with previous research. The in-hospital and 30 day mortality rates are high.

  17. Fault detection approach based on Bond Graph observers: Hydraulic System Case Study

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    Ghada Saoudi

    2016-10-01

    Full Text Available The present paper deals with a bond graph procedure to design graphical observers for fault detection purpose. First of all, a bond Graph approach to build a graphical proportional observer is shown. The estimators’ performance for fault detection purpose is improved using a residual sensitivity analysis to actuator, structural and parametric faults. For uncertain bond graph models in linear fractional transformation LFT, the method is extended to build a graphical proportional-integralPI observer more robust to the presence of parameter uncertainties. The proposed methods allows the computing of the gain matrix graphically using causal paths and loops on the bond graph model of the system. As application, the method is used over a hydraulic system. The simulation results show the dynamic behavior of system variables and the performance of the developed graphical observers

  18. US Air Force Base Observations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Hourly observations taken by U.S. Air Force personnel at bases in the United States and around the world. Foreign observations concentrated in the Middle East and...

  19. Immigrants’ use of emergency primary health care in Norway: a registry-based observational study

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    Sandvik Hogne

    2012-09-01

    Full Text Available Abstract Background Emigrants are often a selected sample and in good health, but migration can have deleterious effects on health. Many immigrant groups report poor health and increased use of health services, and it is often claimed that they tend to use emergency primary health care (EPHC services for non-urgent purposes. The aim of the present study was to analyse immigrants’ use of EPHC, and to analyse variations according to country of origin, reason for immigration, and length of stay in Norway. Methods We conducted a registry based study of all immigrants to Norway, and a subsample of immigrants from Poland, Germany, Iraq and Somalia, and compared them with native Norwegians. The material comprised all electronic compensation claims for EPHC in Norway during 2008. We calculated total contact rates, contact rates for selected diagnostic groups and for services given during consultations. Adjustments for a series of socio-demographic and socio-economic variables were done by multiple logistic regression analyses. Results Immigrants as a whole had a lower contact rate than native Norwegians (23.7% versus 27.4%. Total contact rates for Polish and German immigrants (mostly work immigrants were 11.9% and 7.0%, but for Somalis and Iraqis (mostly asylum seekers 31.8% and 33.6%. Half of all contacts for Somalis and Iraqis were for non-specific pain, and they had relatively more of their contacts during night than other groups. Immigrants’ rates of psychiatric diagnoses were low, but increased with length of stay in Norway. Work immigrants suffered less from respiratory and gastrointestinal infections, but had more injuries and higher need for sickness certification. All immigrant groups, except Germans, were more often given a sickness certificate than native Norwegians. Use of interpreter was reduced with increasing length of stay. All immigrant groups had an increased need for long consultations, while laboratory tests were most often used

  20. Study on Chaotic Fault Tolerant Synchronization Control Based on Adaptive Observer

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    Dongming Chen

    2014-01-01

    Full Text Available Aiming at the abrupt faults of the chaotic system, an adaptive observer is proposed to trace the states of the master system. The sufficient conditions for synchronization of such chaotic systems are also derived. Then the feasibility and effectiveness of the proposed method are illustrated via numerical simulations of chaotic Chen system. Finally, the proposed synchronization schemes are applied to secure communication system successfully. The experimental results demonstrate that the employed observer can manage real-time fault diagnosis and parameter identification as well as states tracing of the master system, and so the synchronization of master system and slave system is achieved.

  1. Prehospital score for acute disease: a community-based observational study in Japan

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    Fujiwara Hidekazu

    2007-10-01

    Full Text Available Abstract Background Ambulance usage in Japan has increased consistently because it is free under the national health insurance system. The introduction of refusal for ambulance transfer is being debated nationally. The purpose of the present study was to investigate the relationship between prehospital data and hospitalization outcome for acute disease patients, and to develop a simple prehospital evaluation tool using prehospital data for Japan's emergency medical service system. Methods The subjects were 9,160 consecutive acute disease patients aged ≥ 15 years who were transferred to hospital by Kishiwada City Fire Department ambulance between July 2004 and March 2006. The relationship between prehospital data (age, systolic blood pressure, pulse rate, respiration rate, level of consciousness, SpO2 level and ability to walk and outcome (hospitalization or non-hospitalization was analyzed using logistic regression models. The prehospital score component of each item of prehospital data was determined by beta coefficients. Eligible patients were scored retrospectively and the distribution of outcome was examined. For patients transported to the two main hospitals, outcome after hospitalization was also confirmed. Results A total of 8,330 (91% patients were retrospectively evaluated using a prehospital score with a maximum value of 14. The percentage of patients requiring hospitalization rose from 9% with score = 0 to 100% with score = 14. With a cut-off point score ≥ 2, the sensitivity, specificity, positive predictive value and negative predictive value were 97%, 16%, 39% and 89%, respectively. Among the 6,498 patients transported to the two main hospitals, there were no deaths at scores ≤ 1 and the proportion of non-hospitalization was over 90%. The proportion of deaths increased rapidly at scores ≥ 11. Conclusion The prehospital score could be a useful tool for deciding the refusal of ambulance transfer in Japan's emergency medical

  2. Confounding in observational studies based on large health care databases: problems and potential solutions - a primer for the clinician.

    Science.gov (United States)

    Nørgaard, Mette; Ehrenstein, Vera; Vandenbroucke, Jan P

    2017-01-01

    Population-based health care databases are a valuable tool for observational studies as they reflect daily medical practice for large and representative populations. A constant challenge in observational designs is, however, to rule out confounding, and the value of these databases for a given study question accordingly depends on completeness and validity of the information on confounding factors. In this article, we describe the types of potential confounding factors typically lacking in large health care databases and suggest strategies for confounding control when data on important confounders are unavailable. Using Danish health care databases as examples, we present the use of proxy measures for important confounders and the use of external adjustment. We also briefly discuss the potential value of active comparators, high-dimensional propensity scores, self-controlled designs, pseudorandomization, and the use of positive or negative controls.

  3. Confounding in observational studies based on large health care databases: problems and potential solutions – a primer for the clinician

    Science.gov (United States)

    Nørgaard, Mette; Ehrenstein, Vera; Vandenbroucke, Jan P

    2017-01-01

    Population-based health care databases are a valuable tool for observational studies as they reflect daily medical practice for large and representative populations. A constant challenge in observational designs is, however, to rule out confounding, and the value of these databases for a given study question accordingly depends on completeness and validity of the information on confounding factors. In this article, we describe the types of potential confounding factors typically lacking in large health care databases and suggest strategies for confounding control when data on important confounders are unavailable. Using Danish health care databases as examples, we present the use of proxy measures for important confounders and the use of external adjustment. We also briefly discuss the potential value of active comparators, high-dimensional propensity scores, self-controlled designs, pseudorandomization, and the use of positive or negative controls.

  4. Spatial and Temporal Variability of Aerosol Vertical Distribution Based on Lidar Observations: A Haze Case Study over Jinhua Basin

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    Wanchun Zhang

    2015-01-01

    Full Text Available The impacts of haze emphasized significance of hazards for human activities and importance of observations of aerosol vertical distribution. This study aimed to analyze the aerosol vertical distribution during a haze case at temporal and spatial aspects, using space-borne and ground-based Lidar observations over Jinhua Basin, Zhejiang province, as well as the Hybrid Single-Particle Lagrangian Integrated Trajectory (HSPLIT model and optical situ monitoring at Jinhua site. The results highlight three pollution peaks above the surface located in the upper and lower boundary layer in Jinhua Basin. The trajectory analysis shows the pollutants inside and outside the planetary boundary layer from different sources. Planetary boundary layer height (PBLH obtained from the space-borne Lidar observations was compared with that from ground-based Lidar observations. The absolute error between the two instruments is about 0.193 km. It is illustrated that the space-borne Lidar is an effective instrument for obtaining regional aerosol pollution in vertical section. Pollution transport near the ground is closely related with the terrain condition.

  5. Space-Based Observation Technology

    Science.gov (United States)

    2007-11-02

    jusqu’ici par des systèmes aéroportés, par des systèmes spatiaux. Les capteurs spatiaux sont des capteurs radar et optiques . Les capteurs optiques ...de l’observation de la terre à partir de capteurs spatiaux offre de nombreux avantages par rapport à l’observation à partir de capteurs terrestres...résolution optique . Le SAR a également d’autres fonctionnalités telles que la classification basée sur les techniques Doppler ou la polarimétrie, la

  6. Stem cell-based treatments against stroke: observations from human proof-of-concept studies and considerations regarding clinical applicability

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    Thorsten Roland Doeppner

    2014-10-01

    Full Text Available Ischemic stroke remains a heavy burden for industrialized countries. The only causal therapy is the recanalization of occluded vessels via thrombolysis, which due to a narrow time window still can be offered only to a minority of patients. Since the majority of patients continues to exhibit neurological deficits even following successful thrombolysis, restorative therapies are urgently needed that promote brain remodeling and repair once stroke injury has occurred. Due to their unique properties of action, stem cell-based strategies gained increasing interest during recent years. Using various stroke models in both rodents and primates, the transplantation of stem cells, namely of bone marrow derived mesenchymal stem cells (MSCs or neural progenitor cells (NPCs, has been shown to promote neurological recovery most likely via indirect bystander actions. In view of promising observations, clinical proof-of-concept studies are currently under way, in which effects of stem and precursor cells are evaluated in human stroke patients. In this review we summarize already published studies, which due to the broad experience in other medical contexts mostly employed bone marrow-derived MSCs by means of intravenous transplantation. With the overall number of clinical trials limited in number, only a fraction of these studies used non-treated control groups, and only single studies were adequately blinded. Despite these limitations, first promising results justify the need for more elaborate clinical trials in order to make stem cell transplantation a success for stroke treatment in the future.

  7. Should All Women with Polycystic Ovary Syndrome Be Screened for Metabolic Parameters?: A Hospital-Based Observational Study

    Science.gov (United States)

    Li, Hui; Li, Lin; Gu, Jian; Li, Yu; Chen, Xiaoli; Yang, Dongzi

    2016-01-01

    This hospital-based observational study aims to estimate differences in metabolic abnormalities between different polycystic ovary syndrome (PCOS) phenotypes and their distribution characteristics. The prevalence of metabolic abnormalities among different PCOS phenotypes, including diabetes mellitus (DM), metabolic syndrome (MS), pre-diabetes mellitus (pre-DM), insulin resistance (IR) and dyslipidemia were compared. A total of 2436 women who were ≥18 years old and who were hospitalized in Sun Yat-Sen University affiliated hospital from 1998 to 2015 in GuangZhou, China, were included in this study. PCOS phenotypes were recorded according to the 2003 Rotterdam criteria, including the polycystic ovary morphology (PCO), hyperandrogenism (HA) and ovulation dysfunction (OD) phenotype (PCO+HA+OD); the ovulation phenotype (PCO+HA); the non-PCO phenotype (HA+OD); and the non-HA phenotype (PCO+OD). Notably, 56% of the patients had the classic phenotype (PCO+HA+OD). Importantly, there was no significant difference in the prevalence of metabolic abnormalities or the distribution characteristics of the metabolic abnormalities among these four PCOS phenotypes. Our study supports the notion that metabolic abnormalities and the distribution characteristics of metabolic abnormalities should not be used to distinguish among the various clinical PCOS phenotypes. PMID:27902723

  8. MRI-based comparative study of different mild cognitive impairment subtypes: protocol for an observational case–control study

    Science.gov (United States)

    Yu, Yang; Zhao, Weina; Li, Siou; Yin, Changhao

    2017-01-01

    Introduction Amnestic mild cognitive impairment (aMCI) and vascular mild cognitive impairment (VaMCI) comprise the 2 main types of mild cognitive impairment (MCI). The first condition generally progresses to Alzheimer's disease, whereas the second is likely to develop into vascular dementia (VD). The brain structure and function of patients with MCI differ from those of normal elderly individuals. However, whether brain structures or functions differ between these 2 MCI subtypes has not been studied. This study is designed to analyse neuroimages of brain in patients with VaMCI and aMCI using multimodality MRI (structural MRI (sMRI), functional MRI and diffusion tensor imaging (DTI)). Methods and analysis In this study, 80 participants diagnosed with aMCI, 80 participants diagnosed with VaMCI, and 80 age-matched, gender-matched and education-matched normal controls (NCs) will be recruited to the Hongqi Hospital of Mudanjiang Medical University, Heilongjiang, China. All participants will undergo neuroimaging and neuropsychological evaluations. The primary outcome measures will be (1) microstructural alterations revealed by multimodal MRIs, including sMRI, resting-state functional MRI and DTI; and (2) a neuropsychological evaluation, including the Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Auditory Verbal Learning Test (AVLT), Memory and Executive Screening (MES), trail making test, Stroop colour naming condition and Clinical Dementia Rating (CDR) scale, to evaluate global cognition, memory function, attention, visuospatial skills, processing speed, executive function and emotion, respectively. Trial registration number NCT02706210; Pre-results. PMID:28274963

  9. Object-based change detection in rapid urbanization regions with remotely sensed observations: a case study of Shenzhen, China

    Science.gov (United States)

    He, Lihuang; Dong, Guihua; Wang, Wei-Min; Yang, Lijun; Liang, Hong

    2013-10-01

    China, the most populous country on Earth, has experienced rapid urbanization which is one of the main causes of many environmental and ecological problems. Therefore, the monitoring of rapid urbanization regions and the environment is of critical importance for their sustainable development. In this study, the object-based classification is employed to detect the change of land cover in Shenzhen, which is located in South China and has been urbanized rapidly in recent three decades. First, four Landsat TM images, which were acquired on 1990, 2000 and 2010, respectively, are selected from the image database. Atmospheric corrections are conducted on these images with improved dark-object subtraction technique and surface meteorological observations. Geometric correction is processed with ground control points derived from topographic maps. Second, a region growing multi-resolution segmentation and a soft nearest neighbour classifier are used to finish object-based classification. After analyzing the fraction of difference classes over time series, we conclude that the comparison of derived land cover classes with socio-economic statistics demonstrates the strong positive correlation between built-up classes and urban population as well as gross GDP and GDPs in second and tertiary industries. Two different mechanisms of urbanization, namely new land development and redevelopment, are revealed. Consequently, we found that, the districts of Shenzhen were urbanized through different mechanisms.

  10. A Sociocultural-Theory-Based Study of the Impact of Mediation during Post- Observation Conferences on Language Teacher Learning

    Science.gov (United States)

    Harvey, Jane

    2011-01-01

    The post-observation conference offers a potentially fecund context for promoting language teacher learning, but very little research has been conducted into how this actually happens. Taking Vygotskian sociocultural theory as its theoretical framework, this study examined the mediational discourse of a series of post-observation conferences…

  11. A study of variation characteristics of Gobi broadband emissivity based on field observational experiments in northwestern China

    Science.gov (United States)

    Zheng, Zhi-yuan; Wei, Zhi-gang; Wen, Zhi-ping; Dong, Wen-jie; Li, Zhen-chao; Wen, Xiao-hang; Zhu, Xian; Chen, Chen; Hu, Shan-shan

    2017-02-01

    Land surface emissivity is a significant variable in energy budgets, land cover assessments, and environment and climate studies. However, the assumption of an emissivity constant is being used in Gobi broadband emissivity (GbBE) parameterization scheme in numerical models because of limited knowledge surrounding the spatiotemporal variation characteristics of GbBE. To address this issue, we analyzed the variation characteristics of GbBE and possible impact factor-surface soil moisture based on long-term continuous and high temporal resolution field observational experiments over a typical Gobi underlying surface in arid and semiarid areas in northwestern China. The results indicate that GbBE has obvious daily and diurnal variation features, especially diurnal cycle characteristics. The multi-year average of the daily average of GbBE is in the range of 0.932 to 0.970 with an average of 0.951 ± 0.008, and the average diurnal GbBE is in the range of 0.880 to 0.940 with an average of 0.906 ± 0.018. GbBE varies with surface soil moisture content. We observed a slight decrease in GbBE with an increase in soil moisture, although this change was not very obvious because of the low soil moisture in this area. Nevertheless, we think that soil moisture must be one of the most significant impact factors on GbBE in arid and semiarid areas. Soil moisture must be taken into account into the parameterization schemes of bare soil broadband emissivity in land surface models. Additional field experiments and studies should be carried out in order to clarify this issue.

  12. Routine delivery of artemisinin-based combination treatment at fixed health facilities reduces malaria prevalence in Tanzania: an observational study

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    Khatib Rashid A

    2012-04-01

    Full Text Available Abstract Background Artemisinin-based combination therapy (ACT has been promoted as a means to reduce malaria transmission due to their ability to kill both asexual blood stages of malaria parasites, which sustain infections over long periods and the immature derived sexual stages responsible for infecting mosquitoes and onward transmission. Early studies reported a temporal association between ACT introduction and reduced malaria transmission in a number of ecological settings. However, these reports have come from areas with low to moderate malaria transmission, been confounded by the presence of other interventions or environmental changes that may have reduced malaria transmission, and have not included a comparison group without ACT. This report presents results from the first large-scale observational study to assess the impact of case management with ACT on population-level measures of malaria endemicity in an area with intense transmission where the benefits of effective infection clearance might be compromised by frequent and repeated re-infection. Methods A pre-post observational study with a non-randomized comparison group was conducted at two sites in Tanzania. Both sites used sulphadoxine-pyrimethamine (SP monotherapy as a first-line anti-malarial from mid-2001 through 2002. In 2003, the ACT, artesunate (AS co-administered with SP (AS + SP, was introduced in all fixed health facilities in the intervention site, including both public and registered non-governmental facilities. Population-level prevalence of Plasmodium falciparum asexual parasitaemia and gametocytaemia were assessed using light microscopy from samples collected during representative household surveys in 2001, 2002, 2004, 2005 and 2006. Findings Among 37,309 observations included in the analysis, annual asexual parasitaemia prevalence in persons of all ages ranged from 11% to 28% and gametocytaemia prevalence ranged from Interpretation The introduction of ACT at

  13. Mixed layer processes of the Arabian Sea Warm Pool during spring intermonsoon: a study based on observational and satellite data

    Digital Repository Service at National Institute of Oceanography (India)

    Sabu, P.; Revichandran, C.

    The relative importance and contribution of various processes in the total heat budget in the mixed layer of the Arabian Sea Warm Pool (ASWP) during spring intermonsoon (March–April 2004) were studied using in situ observations and satellite data...

  14. Health Care Consumption during Pregnancy in relation to Maternal Body Mass Index: A Swedish Population Based Observational Study

    Directory of Open Access Journals (Sweden)

    Elisabeth S. Lindholm

    2015-01-01

    Full Text Available Objective. To assess whether antenatal health care consumption is associated with maternal body mass index (BMI. Design. A register based observational study. Methods. The Swedish Medical Birth Register, the Maternal Health Care Register, and the Inpatient Register were used to determine antenatal health care consumption according to BMI categories for primiparous women with singleton pregnancies, from 2006 to 2008, n=71,638. Pairwise comparisons among BMI groups are obtained post hoc by Tukey HSD test. Result. Obese women were more often admitted for in-patient care (p<0.001, had longer antenatal hospital stays (p<0.001, and were more often sick-listed by an obstetrician (p<0.001 during their pregnancy, compared to women with normal weight women. Preeclampsia was more than four times as common, hypertension five times as common, and gestational diabetes 11 times as common when comparing in-patient care, obese to normal weight women (p<0.001 for all comparisons. Underweight mothers had longer stay in hospitals (p<0.05 and hydronephrosis and hyperemesis gravidarum were more than twice as common (both p<0.001. Conclusion. Obese and underweight mothers consumed significantly more health care resources and obese women were significantly more often sick-listed during their pregnancy when compared to pregnant women of normal weight.

  15. Does delay in diagnosing colorectal cancer in symptomatic patients affect tumor stage and survival? A population-based observational study

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    Visser Otto

    2010-06-01

    Full Text Available Abstract Background Diagnosing colorectal cancer (CRC at an early stage improves survival. To what extent any delay affects outcome once patients are symptomatic is still unclear. Our objectives were to evaluate the association between diagnostic delay and survival in symptomatic patients with early stage CRC and late stage CRC. Methods Prospective population-based observational study evaluating daily clinical practice in Northern Holland. Diagnostic delay was determined through questionnaire-interviews. Dukes' stage was classified into two groups: early stage (Dukes A or B and late stage (Dukes C or D cancer. Patients were followed up for 3.5 years after diagnosis. Results In total, 272 patients were available for analysis. Early stage CRC was present in 136 patients while 136 patients had late stage CRC. The mean total diagnostic delay (SE was 31 (1.5 weeks in all CRC patients. No significant difference was observed in the mean total diagnostic delay in early versus late stage CRC (p = 0.27. In early stage CRC, no difference in survival was observed between patients with total diagnostic delay shorter and longer than the median (Kaplan-Meier, log-rank p = 0.93. In late stage CRC, patients with a diagnostic delay shorter than the median had a shorter survival than patients with a diagnostic delay longer than the median (log-rank p = 0.01. In the multivariate Cox regression model with survival as dependent variable and median delay, age, open access endoscopy, number and type of symptoms as independent variables, the odd's ratio for survival in patients with long delay (>median versus short delay (≤median was 1.8 (95% confidence interval (CI 1.1 to 3.0; p = 0.01. Tumor-site was not associated with patient survival. When separating late stage CRC in Dukes C and Dukes D tumors, a shorter delay was associated with a shorter survival in Dukes D tumors only and not in Dukes C tumors. Conclusion In symptomatic CRC patients, a longer diagnostic and

  16. Association between Perceived Value and Self-Medication with Antibiotics: An Observational Study Based on Health Belief Model Theory

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    Annisa N. Insany

    2015-06-01

    Full Text Available High prevalence of self medication with antibiotics can increase the probability of irrational use of antibiotics which may lead antibiotics resistance. Thus, shifting of behavior is required to minimize the irrational use of antibiotics. This study was aimed to determine the association between public perceived value and self-medication with antibiotics which can be used to develop an intervention model in order to reduce the practice of self-medication with antibiotics. An observational study was conducted during the period of November–December 2014.The subjects were patients who visit primary health care facilities in Bandung. A structured-interview that has been validated was used to investigate the association between perceived value and self-medication behavior based on the Health Belief Model theory (perceived susceptibility, benefits, barrier, and cues to action. Approximately 506 respondents were drawn randomly from 43 community healthcare centers and 8 pharmacies. Data was analyzed by using descriptive statistics and logistic regression (CI 95%, α = 5%. Validity and reliability of the questionnaire were shown with a correlation coefficient of >0.3 and a cronbach-alpha value of 0.719, respectively. We found that 29.45% of respondents practiced self-medication with antibiotics over the last six months. Additionally, there was no significant association between the perceived susceptibility, benefits, barrier, and cues to action with self-medication behavior (p>0.05. Easiness to access antibiotics without prescription was presumed as a factor that contribute to self-medication with antibiotics, therefore strict regulation in antibiotics use is very needed as a basic intervention to decrease self-medication with antibiotic.

  17. Cardiovascular risk with non-steroidal anti-inflammatory drugs: systematic review of population-based controlled observational studies.

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    Patricia McGettigan

    2011-09-01

    Full Text Available BACKGROUND: Randomised trials have highlighted the cardiovascular risks of non-steroidal anti-inflammatory drugs (NSAIDs in high doses and sometimes atypical settings. Here, we provide estimates of the comparative risks with individual NSAIDs at typical doses in community settings. METHODS AND FINDINGS: We performed a systematic review of community-based controlled observational studies. We conducted comprehensive literature searches, extracted adjusted relative risk (RR estimates, and pooled the estimates for major cardiovascular events associated with use of individual NSAIDs, in different doses, and in populations with low and high background risks of cardiovascular events. We also compared individual drugs in pair-wise (within study analyses, generating ratios of RRs (RRRs. Thirty case-control studies included 184,946 cardiovascular events, and 21 cohort studies described outcomes in >2.7 million exposed individuals. Of the extensively studied drugs (ten or more studies, the highest overall risks were seen with rofecoxib, 1.45 (95% CI 1.33, 1.59, and diclofenac, 1.40 (1.27, 1.55, and the lowest with ibuprofen, 1.18 (1.11, 1.25, and naproxen, 1.09 (1.02, 1.16. In a sub-set of studies, risk was elevated with low doses of rofecoxib, 1.37 (1.20, 1.57, celecoxib, 1.26 (1.09, 1.47, and diclofenac, 1.22 (1.12, 1.33, and rose in each case with higher doses. Ibuprofen risk was seen only with higher doses. Naproxen was risk-neutral at all doses. Of the less studied drugs etoricoxib, 2.05 (1.45, 2.88, etodolac, 1.55 (1.28, 1.87, and indomethacin, 1.30 (1.19, 1.41, had the highest risks. In pair-wise comparisons, etoricoxib had a higher RR than ibuprofen, RRR = 1.68 (99% CI 1.14, 2.49, and naproxen, RRR = 1.75 (1.16, 2.64; etodolac was not significantly different from naproxen and ibuprofen. Naproxen had a significantly lower risk than ibuprofen, RRR = 0.92 (0.87, 0.99. RR estimates were constant with different background risks for

  18. Association between the Value-Based Purchasing pay for performance program and patient mortality in US hospitals: observational study

    Science.gov (United States)

    Figueroa, Jose F; Tsugawa, Yusuke; Zheng, Jie; Orav, E John

    2016-01-01

    Objective To determine the impact of the Hospital Value-Based Purchasing (HVBP) program—the US pay for performance program introduced by Medicare to incentivize higher quality care—on 30 day mortality for three incentivized conditions: acute myocardial infarction, heart failure, and pneumonia. Design Observational study. Setting 4267 acute care hospitals in the United States: 2919 participated in the HVBP program and 1348 were ineligible and used as controls (44 in general hospitals in Maryland and 1304 critical access hospitals across the United States). Participants 2 430 618 patients admitted to US hospitals from 2008 through 2013. Main outcome measures 30 day risk adjusted mortality for acute myocardial infarction, heart failure, and pneumonia using a patient level linear spline analysis to examine the association between the introduction of the HVBP program and 30 day mortality. Non-incentivized, medical conditions were the comparators. A secondary outcome measure was to determine whether the introduction of the HVBP program was particularly beneficial for a subgroup of hospital—poor performers at baseline—that may benefit the most. Results Mortality rates of incentivized conditions in hospitals participating in the HVBP program declined at −0.13% for each quarter during the preintervention period and −0.03% point difference for each quarter during the post-intervention period. For non-HVBP hospitals, mortality rates declined at −0.14% point difference for each quarter during the preintervention period and −0.01% point difference for each quarter during the post-intervention period. The difference in the mortality trends between the two groups was small and non-significant (difference in difference in trends −0.03% point difference for each quarter, 95% confidence interval −0.08% to 0.13% point difference, P=0.35). In no subgroups of hospitals was HVBP associated with better outcomes, including poor performers at baseline

  19. Place and cause of death in centenarians: a population-based observational study in England, 2001 to 2010.

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    Catherine J Evans

    2014-06-01

    Full Text Available Centenarians are a rapidly growing demographic group worldwide, yet their health and social care needs are seldom considered. This study aims to examine trends in place of death and associations for centenarians in England over 10 years to consider policy implications of extreme longevity.This is a population-based observational study using death registration data linked with area-level indices of multiple deprivations for people aged ≥100 years who died 2001 to 2010 in England, compared with those dying at ages 80-99. We used linear regression to examine the time trends in number of deaths and place of death, and Poisson regression to evaluate factors associated with centenarians' place of death. The cohort totalled 35,867 people with a median age at death of 101 years (range: 100-115 years. Centenarian deaths increased 56% (95% CI 53.8%-57.4% in 10 years. Most died in a care home with (26.7%, 95% CI 26.3%-27.2% or without nursing (34.5%, 95% CI 34.0%-35.0% or in hospital (27.2%, 95% CI 26.7%-27.6%. The proportion of deaths in nursing homes decreased over 10 years (-0.36% annually, 95% CI -0.63% to -0.09%, p = 0.014, while hospital deaths changed little (0.25% annually, 95% CI -0.06% to 0.57%, p = 0.09. Dying with frailty was common with "old age" stated in 75.6% of death certifications. Centenarians were more likely to die of pneumonia (e.g., 17.7% [95% CI 17.3%-18.1%] versus 6.0% [5.9%-6.0%] for those aged 80-84 years and old age/frailty (28.1% [27.6%-28.5%] versus 0.9% [0.9%-0.9%] for those aged 80-84 years and less likely to die of cancer (4.4% [4.2%-4.6%] versus 24.5% [24.6%-25.4%] for those aged 80-84 years and ischemic heart disease (8.6% [8.3%-8.9%] versus 19.0% [18.9%-19.0%] for those aged 80-84 years than were younger elderly patients. More care home beds available per 1,000 population were associated with fewer deaths in hospital (PR 0.98, 95% CI 0.98-0.99, p<0.001.Centenarians are more likely to have causes of death certified as

  20. A MiniReview of the Use of Hospital-based Databases in Observational Inpatient Studies of Drugs

    DEFF Research Database (Denmark)

    Larsen, Michael Due; Cars, Thomas; Hallas, Jesper

    2013-01-01

    The majority of pharmacoepidemiological data resources are based on data generated in primary health care. Although inpatient data resources have existed since the 1960s, inpatient pharmacoepidemiological studies are relatively scarce. The objectives of this MiniReview were to describe pharmacoep......The majority of pharmacoepidemiological data resources are based on data generated in primary health care. Although inpatient data resources have existed since the 1960s, inpatient pharmacoepidemiological studies are relatively scarce. The objectives of this MiniReview were to describe...... pharmacoepidemiological studies in hospital settings and the underlying databases to provide an overview of research questions addressed by such databases. The studies were retrieved by chain searching. We included pharmacoepidemiological studies in hospital settings containing data on inpatient drug use. Twelve...... inpatient databases in Asia, the United States and Europe were found. Most databases were automatically collected from claims data or generated from electronic medical records. The contents of the databases varied as well as the potential for linkage with other data sources such as laboratory and outpatient...

  1. Countesthorpe College: an observant study

    Science.gov (United States)

    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)

  2. A large web-based observer reliability study of early ischaemic signs on computed tomography. The Acute Cerebral CT Evaluation of Stroke Study (ACCESS.

    Directory of Open Access Journals (Sweden)

    Joanna M Wardlaw

    Full Text Available BACKGROUND: Early signs of ischaemic stroke on computerised tomography (CT scanning are subtle but CT is the most widely available diagnostic test for stroke. Scoring methods that code for the extent of brain ischaemia may improve stroke diagnosis and quantification of the impact of ischaemia. METHODOLOGY AND PRINCIPAL FINDINGS: We showed CT scans from patients with acute ischaemic stroke (n = 32, with different patient characteristics and ischaemia signs to doctors in stroke-related specialties world-wide over the web. CT scans were shown twice, randomly and blindly. Observers entered their scan readings, including early ischaemic signs by three scoring methods, into the web database. We compared observers' scorings to a reference standard neuroradiologist using area under receiver operator characteristic curve (AUC analysis, Cronbach's alpha and logistic regression to determine the effect of scales, patient, scan and observer variables on detection of early ischaemic changes. Amongst 258 readers representing 33 nationalities and six specialties, the AUCs comparing readers with the reference standard detection of ischaemic signs were similar for all scales and both occasions. Being a neuroradiologist, slower scan reading, more pronounced ischaemic signs and later time to CT all improved detection of early ischaemic signs and agreement on the rating scales. Scan quality, stroke severity and number of years of training did not affect agreement. CONCLUSIONS: Large-scale observer reliability studies are possible using web-based tools and inform routine practice. Slower scan reading and use of CT infarct rating scales improve detection of acute ischaemic signs and should be encouraged to improve stroke diagnosis.

  3. A Large Web-Based Observer Reliability Study of Early Ischaemic Signs on Computed Tomography. The Acute Cerebral CT Evaluation of Stroke Study (ACCESS)

    Science.gov (United States)

    Wardlaw, Joanna M.; von Kummer, Rüdiger; Farrall, Andrew J.; Chappell, Francesca M.; Hill, Michael; Perry, David

    2010-01-01

    Background Early signs of ischaemic stroke on computerised tomography (CT) scanning are subtle but CT is the most widely available diagnostic test for stroke. Scoring methods that code for the extent of brain ischaemia may improve stroke diagnosis and quantification of the impact of ischaemia. Methodology and Principal Findings We showed CT scans from patients with acute ischaemic stroke (n = 32, with different patient characteristics and ischaemia signs) to doctors in stroke-related specialties world-wide over the web. CT scans were shown twice, randomly and blindly. Observers entered their scan readings, including early ischaemic signs by three scoring methods, into the web database. We compared observers' scorings to a reference standard neuroradiologist using area under receiver operator characteristic curve (AUC) analysis, Cronbach's alpha and logistic regression to determine the effect of scales, patient, scan and observer variables on detection of early ischaemic changes. Amongst 258 readers representing 33 nationalities and six specialties, the AUCs comparing readers with the reference standard detection of ischaemic signs were similar for all scales and both occasions. Being a neuroradiologist, slower scan reading, more pronounced ischaemic signs and later time to CT all improved detection of early ischaemic signs and agreement on the rating scales. Scan quality, stroke severity and number of years of training did not affect agreement. Conclusions Large-scale observer reliability studies are possible using web-based tools and inform routine practice. Slower scan reading and use of CT infarct rating scales improve detection of acute ischaemic signs and should be encouraged to improve stroke diagnosis. PMID:21209901

  4. Space-based long-term observation of shrinking grassland habitat: A case-study from central India

    Science.gov (United States)

    Lele, N.; Singh, C. P.; Singh, R. P.; Chauhan, J. S.; Parihar, J. S.

    2015-10-01

    Grassland ecosystem is critical for survival of herbivores and plays an important role in conservation and management of wildlife. These habitats are widely studied for various issues, including biodiversity, biomass assessment, carrying capacity, etc. Woody species ingression in grasslands is one such important aspect that needs critical attention in protected area as this leads to shrinking of grasslands habitat. This study presents a case of Ronda grassland in Kanha National Park - a well-known protected area in India, known for its herbivore diversity and hard-ground Barasingha (Rucervus duvaceli branderi), in particular. Long-term satellite observation for five decades was carried out to understand spatio-temporal changes. Declassified Corona satellite data, aerial photographs along with satellite datasets in the subsequent period were utilised for this study. The study revealed that 88 ha (16% of Ronda and surrounding) have been ingressed during 1962-2011, in and around Ronda grassland of Kanha National Park. Rates of ingression on linear transects were found to be 60-120 m per decade. Field studies and NDVI analysis along the edge of grassland pixels as well as inside region using 1972 as baseline data, indicated woody vegetation replacing area of grassland. It was noted that Butea monosperma is invading more than other species in Ronda grassland, particularly along the stream where moisture availability is higher. Grassland habitats in Kanha are thus shrinking and thus leading to reduction in the area available for herbivore population which has increased in recent years. This can lead to severe impact on carrying capacity of these grasslands.

  5. Frequency of GP communication addressing the patient's resources and coping strategies in medical interviews: a video-based observational study

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    Finset Arnstein

    2009-07-01

    Full Text Available Abstract Background There is increasing focus on patient-centred communicative approaches in medical consultations, but few studies have shown the extent to which patients' positive coping strategies and psychological assets are addressed by general practitioners (GPs on a regular day at the office. This study measures the frequency of GPs' use of questions and comments addressing their patients' coping strategies or resources. Methods Twenty-four GPs were video-recorded in 145 consultations. The consultations were coded using a modified version of the Roter Interaction Analysis System. In this study, we also developed four additional coding categories based on cognitive therapy and solution-focused therapy: attribution, resources, coping, and solution-focused techniques. The reliability between coders was established, a factor analysis was applied to test the relationship between the communication categories, and a tentative validating exercise was performed by reversed coding. Results Cohen's kappa was 0.52 between coders. Only 2% of the utterances could be categorized as resource or coping oriented. Six GPs contributed 59% of these utterances. The factor analysis identified two factors, one task oriented and one patient oriented. Conclusion The frequency of communication about coping and resources was very low. Communication skills training for GPs in this field is required. Further validating studies of this kind of measurement tool are warranted.

  6. Breakdown study based on direct in situ observation of inner surfaces of an rf accelerating cavity during a high-gradient test

    Science.gov (United States)

    Abe, Tetsuo; Kageyama, Tatsuya; Sakai, Hiroshi; Takeuchi, Yasunao; Yoshino, Kazuo

    2016-10-01

    We have developed normal-conducting accelerating single-cell cavities with a complete higher-order-mode (HOM) heavily damped structure, into which we feed a 508.9-MHz continuous wave. During a high-gradient test of the second production version of the cavity, we performed a breakdown study based on direct in situ observation of the inner surfaces of the cavity. This paper presents our experimental findings obtained from this observation.

  7. Observational Study of Travelers' Diarrhea.

    Science.gov (United States)

    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

  8. Systematic study of intermediate-scale structures of equatorial plasma irregularities in the ionosphere based on CHAMP observations

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    Hermann eLühr

    2014-03-01

    Full Text Available Equatorial spread-F ionospheric plasma irregularities on the night-side, commonly called equatorial plasma bubbles (EPB, include electron density variations over a wide range of spatial scales. Here we focus on intermediate-scale structures ranging from 100 m to 10 km, which play an important role in the evolution of EPBs. High-resolution CHAMP magnetic field measurements sampled along north-south track at 50 Hz are interpreted in terms of diamagnetic effect for illustrating the details of electron density variations. We provide the first comprehensive study on intermediate-scale density structures associated with EPBs, covering a whole solar cycle from 2000 to 2010. The large number of detected events, almost 9000, allows us to draw a detailed picture of the plasma fine structure. The occurrence of intermediate-scale events is strongly favoured by high solar flux. During times of F10.7 < 100 sfu practically no events were observed. The longitudinal distribution of our events with respect to season or local time agrees well with that of the EPBs, qualifying the fine structure as a common feature, but the occurrence rates are smaller by a factor of 4 during the period 2000-2005. Largest amplitude electron density variations appear at the poleward boundaries of plasma bubbles. Above the dip-equator recorded amplitudes are small and fall commonly below our resolution. Events can generally be found at local times between 19 and 24 LT, with a peak lasting from 20 to 22 LT. The signal spectrum can be approximated by a power law. Over the frequency range 1 – 25 Hz we observe spectral indices between -1.4 and -2.6 with peak occurrence rates around -1.9. There is a weak dependence observed of the spectral index on local time. Towards later hours the spectrum becomes shallower. Similarly for the latitude dependence, there is a preference of shallower spectra for latitudes poleward of the ionisation anomaly crest. Our data suggest that the generation of

  9. A General Framework for Considering Selection Bias in EHR-Based Studies: What Data Are Observed and Why?

    Science.gov (United States)

    Haneuse, Sebastien; Daniels, Michael

    2016-01-01

    Electronic health records (EHR) data are increasingly seen as a resource for cost-effective comparative effectiveness research (CER). Since EHR data are collected primarily for clinical and/or billing purposes, their use for CER requires consideration of numerous methodologic challenges including the potential for confounding bias, due to a lack of randomization, and for selection bias, due to missing data. In contrast to the recent literature on confounding bias in EHR-based CER, virtually no attention has been paid to selection bias possibly due to the belief that standard methods for missing data can be readily-applied. Such methods, however, hinge on an overly simplistic view of the available/missing EHR data, so that their application in the EHR setting will often fail to completely control selection bias. Motivated by challenges we face in an on-going EHR-based comparative effectiveness study of choice of antidepressant treatment and long-term weight change, we propose a new general framework for selection bias in EHR-based CER. Crucially, the framework provides structure within which researchers can consider the complex interplay between numerous decisions, made by patients and health care providers, which give rise to health-related information being recorded in the EHR system, as well as the wide variability across EHR systems themselves. This, in turn, provides structure within which: (i) the transparency of assumptions regarding missing data can be enhanced, (ii) factors relevant to each decision can be elicited, and (iii) statistical methods can be better aligned with the complexity of the data. PMID:27668265

  10. A study of M Mira variables based on IRAS LRS observations. II. Model fits and derived parameters for 109 Miras

    Energy Technology Data Exchange (ETDEWEB)

    Onaka, T.; Jong, T. de; Willems, F.J. (Amsterdam Univ. (NL))

    1989-12-01

    We have fitted dust shell models to the IRAS LRS spectra of 109 M Mira variables. The main assumptions in the model calculations are: (i) the dust shell is spherical and optically thin, (ii) the dust grains consist of aluminum oxide and amorphous magnesium silicate, (iii) the mass loss rate is constant, (iv) the stellar photosphere is characterized by R = 3 x 10{sup 13} cm and T = 2500 K. Best fit models are calculated for each star. A model is completely determined by five parameters: the dust temperatures at the inner boundaries of the aluminum oxide and silicate dust shells, the column densities of each dust grain component, and the distance to the star. It turns out that the 1 - 200 {mu}m infrared energy distributions calculated for the best fit parameters also provide quite satisfactory fits to the observed near- and far-infrared broad-band data for most sources. The material presented here forms the basis for a study of dust condensation in the circumstellar shells around Mira variables.

  11. A multi-transition study of molecules toward NGC 1068 based on high-resolution imaging observations with ALMA

    Science.gov (United States)

    Nakajima, Taku; Takano, Shuro; Kohno, Kotaro; Harada, Nanase; Herbst, Eric; Tamura, Yoichi; Izumi, Takuma; Taniguchi, Akio; Tosaki, Tomoka

    2015-02-01

    We present 0.8-mm band molecular images and spectra obtained with the Atacama Large Millimeter/submillimeter Array (ALMA) toward one of the nearest galaxies with an active galactic nucleus (AGN), NGC 1068. Distributions of CO isotopic species (13CO and C18O) J = 3-2, CN N = 3-2, and CS J = 7-6 are observed toward the circumnuclear disk (CND) and a part of the starburst ring with an angular resolution of ˜ 1.3" × 1.2". The physical properties of these molecules and shock-related molecules, such as HNCO, CH3CN, SO, and CH3OH, detected in the 3-mm band were estimated using rotation diagrams under the assumption of local thermodynamic equilibrium. The rotational temperatures of the CO isotopic species and the shock-related molecules in the CND are, respectively, 14-22 K and upper limits of 20-40 K. Although the column densities of the CO isotopic species in the CND are only from one-fifth to one-third of that in the starburst ring, those of the shock-related molecules are enhanced by a factor of 3-10 in the CND. We also discuss the chemistry of each species, and compare the fractional abundances in the CND and starburst ring with those of Galactic sources such as cold cores, hot cores, and shocked molecular clouds in order to study the overall characteristics. We find that the abundances of shock-related molecules are more similar to abundances in hot cores and/or shocked clouds than to cold cores. The CND hosts relatively complex molecules, which are often associated with shocked molecular clouds or hot cores. Because a high X-ray flux can dissociate these molecules, they must also reside in regions shielded from X-rays.

  12. Demographic and circumstantial accounts of burn mortality in Cape Town, South Africa, 2001-2004: An observational register based study

    Directory of Open Access Journals (Sweden)

    Laflamme L

    2009-10-01

    Full Text Available Abstract Background Burns are a persisting public health problem in low- and middle-income countries; however, epidemiologic data for these settings is scarce. South Africa is no exception although there is an emerging knowledge base, especially for paediatric burns. The current study describes the epidemiology of burn mortality across the lifespan in Cape Town (2.9 million inhabitants in 2001, one of the six South African metropolitan centres. Methods The distribution of burn mortality across socio-demographic groups and also their circumstances of occurrence were investigated using four year (2001 to 2004 surveillance data from the National Injury Mortality Surveillance System (n = 1024 cases. Results Burn mortality occurred at a rate of 7.9 per 100 000 person-years (95% CI: 7.3-8.3. Males sustained fatal rates 2.2 times more than that for females (p Conclusion Besides paediatric burns, the high prevalence and circumstances of occurrence of burns among middle age men are a source of concern. There are reasons to believe that this over-representation is a reflection of detrimental living conditions, life-style and poor socio-economic status. It is recommended that there be greater prioritisation of prevention activities that involve the control or management of kerosene heat sources, the provision of alternatives to flammable housing materials, and the implementation of strategies to reduce harmful drinking practices.

  13. Study of diatoms/aqueous solution interface. I. Acid-base equilibria and spectroscopic observation of freshwater and marine species

    Science.gov (United States)

    Gélabert, A.; Pokrovsky, O. S.; Schott, J.; Boudou, A.; Feurtet-Mazel, A.; Mielczarski, J.; Mielczarski, E.; Mesmer-Dudons, N.; Spalla, O.

    2004-10-01

    This work reports on a concerted study of diatom-water interfaces for two marine planktonic ( Thalassiosira weissflogii= TW, Skeletonema costatum= SC) and two freshwater periphytic species ( Achnanthidium minutissimum= AMIN, Navicula minima= NMIN). Proton surface adsorption was measured at 25°C, pH of 3 to 11 and ionic strength of 0.001 to 1.0 M via potentiometric titration using a limited residence time reactor. Electrophoretic mobility of living cells and their frustules was measured as a function of pH and ionic strength. Information on the chemical composition and molecular structure of diatoms surfaces was obtained using FT-IR (in situ attenuated total reflectance) and X-ray Photoelectron Spectroscopy (XPS). The surface area of living cells and their frustules in aqueous solutions was quantified using Small Angle X-ray Scattering Spectroscopy (SAXS). These observations allowed us to identify the nature and to determine the concentration of the major surface functional groups (carboxyl, amine and silanol) responsible for the amphoteric behavior of cell surfaces in aqueous solutions. Taking into account the relative proportion of surface sites inferred from XPS and FT-IR measurements, a surface complexation model of diatom-solution interfaces was generated on the basis of surface titration results. The cell-normalized ratios of the three major surface sites {>COOH}: {>NH 3}: {>SiOH} are 1:1:0.1, 1:10:0, 1:1:0.4 and 1:1:0.3 for TW, SC, AMIN and NMIN, respectively. The total amount of proton/hydroxyl active surface sites for investigated species ranges from 1 (NMIN) to 9 (SC) mmol/g dry weight. Normalization of these site densities to the area of siliceous skeleton yields values between 0.3 (NMIN) and 0.9 mmol/m 2 (SC) which are an order of magnitude higher than corresponding values for organic-free frustules or amorphous silica. This suggests that the amphoteric properties and possibly the affinity for metal adsorption of diatom cultures are essentially

  14. Verbal and physical violence towards hospital- and community-based physicians in the Negev: an observational study

    Directory of Open Access Journals (Sweden)

    Freud Tami

    2005-08-01

    Full Text Available Abstract Background Over recent years there has been an increasing prevalence of verbal and physical violence in Israel, including in the work place. Physicians are exposed to violence in hospitals and in the community. The objective was to characterize acts of verbal and physical violence towards hospital- and community-based physicians. Methods A convenience sample of physicians working in the hospital and community completed an anonymous questionnaire about their experience with violence. Data collection took place between November 2001 and July 2002. One hundred seventy seven physicians participated in the study, 95 from the hospital and 82 from community clinics. The community sample included general physicians, pediatricians, specialists and residents. Results Ninety-nine physicians (56% reported at least one act of verbal violence and 16 physicians (9% reported exposure to at least one act of physical violence during the previous year. Fifty-one hospital physicians (53.7% were exposed to verbal violence and 9 (9.5% to physical violence. Forty-eight community physicians (58.5% were exposed to verbal violence and 7 (8.5% to physical violence. Seventeen community physicians (36.2% compared to eleven hospital physicians (17.2% said that the violence had a negative impact on their family and on their quality of life (p Conclusion Verbal and/or physical violence against physicians is common in both the hospital and in community clinics. The impatience that accompanies waiting times may have a cultural element. Shortening waiting times and providing more information to patients and families could reduce the rate of violence, but a cultural change may also be required.

  15. A study of solar flare energy transport based on coordinated H-alpha and X-ray observations

    Science.gov (United States)

    Canfield, Richard C.; Wulser, Jean-Pierre; Zarro, Dominic M.; Dennis, Brian R.

    1991-01-01

    The temporal evolution of the ratio between H-alpha to nonthermal hard X-ray emission was investigated using coordinated H-alpha and hard- and soft-X-ray observations of five solar flares (on May 7, June 23, June 24, and June 25, 1980 and on April 30, 1985). These observations were used to estimate the emitted flare energy flux F(H-alpha) in H-alpha, the flux of F(2O) energy deposited by nonthermal electrons with energies above 20 keV, and the pressure p(c) of soft X-ray-emitting plasma as functions of time during the impulsive phase of each flare. It was found that the F(H-alpha)/F(2O) ratio shows a power-law dependence on F(2O), with a slope that differs slightly from that predicted by the static thick-target model of solar transport. Results also indicate that the power-law dependence is modified by hydrostatic pressure effects.

  16. An 8-Week Web-Based Weight Loss Challenge With Celebrity Endorsement and Enhanced Social Support: Observational Study

    Science.gov (United States)

    Collins, Clare E; Morgan, Philip J; Callister, Robin

    2013-01-01

    Background Initial engagement and weight loss within Web-based weight loss programs may predict long-term success. The integration of persuasive Web-based features may boost engagement and therefore weight loss. Objective To determine whether an 8-week challenge within a commercial Web-based weight loss program influenced weight loss, website use, and attrition in the short term, when compared to the standard program. Methods De-identified data for participants (mean age 36.7±10.3 years; 86% female) who enrolled in the Biggest Loser Club (BLC) (n=952) and the BLC’s Shannan Ponton Fast Track Challenge (SC) for 8 weeks (n=381) were compared. The BLC program used standard evidence-based website features, with individualized calorie and exercise targets to facilitate a weight loss of 0.5-1 kg per week (–500kcal/day less than estimated energy expenditure). SC used the same website features but in addition promoted greater initial weight loss using a 1200 kcal/day energy intake target and physical activity energy expenditure of 600 kcal/day. SC used persuasive features to facilitate greater user engagement, including offering additional opportunities for social support (eg, webinar meetings with a celebrity personal trainer and social networking) endorsed by a celebrity personal trainer. Self-reported weekly weight records were used to determine weight change after 8 weeks. A primary analysis was undertaken using a generalized linear mixed model (GLMM) with all available weight records for all participants included. Dropout (participants who cancelled their subscription) and nonusage (participants who stopped using the Web-based features) attrition rates at 8 weeks were calculated. The number of participants who accessed each website feature and the total number of days each feature was used were calculated. The difference between attrition rates and website use for the two programs were tested using chi-square and Wilcoxon Rank Sum tests, respectively. Results

  17. Utilities/industries joint study on seismic isolation systems for LWRs. Pt. 2; Observed behaviors of base-isolated general buildings under real earthquakes

    Energy Technology Data Exchange (ETDEWEB)

    Matsumura, Takao; Sato, Shoji; Kato, Muneaki (Kansai Electric Power Co., Inc., Osaka (Japan))

    1991-06-01

    This paper describes the observed behavior of base-isolated buildings under real earthquake conditions. These buildings were constructed by five construction companies participating in the Joint Study on Seismic Isolation Systems for light-water reactors (LWRs). All the buildings are medium- or low-height buildings or reinforced-concrete structures with combinations of laminated rubber bearings or sliding bearings and various damping devices. (orig.).

  18. Study on chaos control of second-order non-autonomous phase-locked loop based on state observer

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Yibo [College of physics and Electronic Information, Anhui Normal University, Wuhu 241000 (China)], E-mail: zhyb26@yahoo.com.cn; Wei Duqu; Luo Xiaoshu [College of Physics and Electronic engineering, Guangxi Normal University, Guilin 541004 (China)

    2009-02-28

    With system parameters falling into a certain area, the second-order non-autonomous phase locked loop (PLL) is experiencing chaotic behavior which is undesirable in system, where it is necessary to estimate the phase of a received signal. In order to control chaos in PLL and drive it to the locked state, dynamical equation for phase error model of PLL is firstly derived. Then, the state values of phase and transient frequency errors were estimated by a state observer. Moreover, by exploiting these state estimations, a non-linear feedback controller is designed. Since the presented controller does not need to change the controlled system structure and not to use any information of system except the system state variables, the designed controller is simple and desirable. Simulation results show that the presented control law is very effective.

  19. A proposal on the study of solar-terrestrial coupling processes with atmospheric radars and ground-based observation network

    Science.gov (United States)

    Tsuda, Toshitaka; Yamamoto, Mamoru; Hashiguchi, Hiroyuki; Shiokawa, Kazuo; Ogawa, Yasunobu; Nozawa, Satonori; Miyaoka, Hiroshi; Yoshikawa, Akimasa

    2016-09-01

    The solar energy can mainly be divided into two categories: the solar radiation and the solar wind. The former maximizes at the equator, generating various disturbances over a wide height range and causing vertical coupling processes of the atmosphere between the troposphere and middle and upper atmospheres by upward propagating atmospheric waves. The energy and material flows that occur in all height regions of the equatorial atmosphere are named as "Equatorial Fountain." These processes from the bottom also cause various space weather effects, such as satellite communication and Global Navigation Satellite System positioning. While, the electromagnetic energy and high-energy plasma particles in the solar wind converge into the polar region through geomagnetic fields. These energy/particle inflow results in auroral Joule heating and ion drag of the atmosphere particularly during geomagnetic storms and substorms. The ion outflow from the polar ionosphere controls ambient plasma constituents in the magnetosphere and may cause long-term variation of the atmosphere. We propose to clarify these overall coupling processes in the solar-terrestrial system from the bottom and from above through high-resolution observations at key latitudes in the equator and in the polar region. We will establish a large radar with active phased array antenna, called the Equatorial Middle and Upper atmosphere radar, in west Sumatra, Indonesia. We will participate in construction of the EISCAT_3D radar in northern Scandinavia. These radars will enhance the existing international radar network. We will also develop a global observation network of compact radio and optical remote sensing equipment from the equator to polar region.

  20. Observation, Sherlock Holmes, and Evidence Based Medicine.

    Science.gov (United States)

    Osborn, John

    2002-01-01

    Sir Arthur Conan Doyle, the creator of the fictional detective Sherlock Holmes, studied medicine at the University of Edinburgh between 1876 and 1881 under Doctor Joseph Bell who emphasised in his teaching the importance of observation, deduction and evidence. Sherlock Holmes was modelled on Joseph Bell. The modern notions of Evidence Based Medicine (EBM) are not new. A very brief indication of some of the history of EBM is presented including a discussion of the important and usually overlooked contribution of statisticians to the Popperian philosophy of EBM.

  1. A Multi-Transition Study of Molecules toward NGC 1068 based on High-Resolution Imaging Observations with ALMA

    CERN Document Server

    Nakajima, Taku; Kohno, Kotaro; Harada, Nanase; Herbst, Eric; Tamura, Yoichi; Izumi, Takuma; Taniguchi, Akio; Tosaki, Tomoka

    2014-01-01

    We present 0.8-mm band molecular images and spectra obtained with the Atacama Large Millimeter/submillimeter Array (ALMA) toward one of the nearest galaxies with an active galactic nucleus (AGN), NGC 1068. Distributions of CO isotopic species ($^{13}$CO and C$^{18}$O) $\\it{J}$ = 3--2, CN $\\it{N}$ = 3--2 and CS $\\it{J}$ = 7--6 are observed toward the circumnuclear disk (CND) and a part of the starburst ring with an angular resolution of $\\sim$1.$^{\\prime\\prime}$3 $\\times$ 1.$^{\\prime\\prime}$2. The physical properties of these molecules and shock-related molecules such as HNCO, CH$_{3}$CN, SO, and CH$_{3}$OH detected in the 3-mm band were estimated using rotation diagrams under the assumption of local thermodynamic equilibrium. The rotational temperatures of the CO isotopic species and the shock-related molecules in the CND are, respectively, 14--22 K and upper limits of 20--40 K. Although the column densities of the CO isotopic species in the CND are only from one-fifth to one-third of that in the starburst ri...

  2. Evaluation of serum ferritin in in type II diabetes mellitus: a hospital based observational study from Dibrugarh, Assam, India

    Directory of Open Access Journals (Sweden)

    Meghna Borah

    2016-11-01

    Conclusions: Therefore, the findings in the present study indicates that serum ferritin was increased in diabetes as long as glycemic control was not achieved and that this increase may contribute to the pathogenesis of this disease as well as in the development of complications. Thus, routine screening for serum ferritin concentration in pre-diabetes and diabetic patients can be done to assess the body iron stores. [Int J Res Med Sci 2016; 4(11.000: 4916-4921

  3. A Left-Sided Prevalence of Lentigo Maligna: A UK Based Observational Study and Review of the Evidence

    Directory of Open Access Journals (Sweden)

    Mark Gorman

    2015-01-01

    Full Text Available Skin cancer has been shown to present asymmetrically, prevalent on the left side of the body, more so in subtypes of cutaneous melanoma such as lentigo maligna. Biases have been linked to cumulative UV light exposure and automobile driving patterns. Though left-right ratios have previously correlated with the side men or women tend to position themselves or countries drive on, more recent trends indicate a consistent left-sided bias. To clarify reasons for changing trends, a review of the evidence base and LM’s laterality in a UK cohort (99 cases 2000–2011 was conducted for the first time. The strong correlation of left-sided excess, found in both genders (ratios 1.381–1.5, P<0.05  X2 0.841, is congruent with more recent findings. Though evidence indicates that driving position is no longer a risk factor for LM, due most likely to improved car window UV protection, it remains the most commonly attributed cause. Understanding phenomena such as UV lights “scatter effect” or that cumulative exposure may not be a significant risk factor helps rationalize older conclusions that would otherwise appear contradictory. The reasons for left-sided excess remain unclear but may be due to factors requiring further research such as the body’s anatomical/embryological asymmetry.

  4. External fixation versus open reduction and internal fixation for tibial pilon fractures: A meta-analysis based on observational studies

    Institute of Scientific and Technical Information of China (English)

    Yi-Chen Meng; Xu-Hui Zhou

    2016-01-01

    Purpose:Tibial pilon fractures remain challenging for an orthopaedic surgeon to repair.External fixation (ExFix) and open reduction and internal fixation (ORIF) are two widely used methods for repairing tibial pilon fractures.However,conclusions of comparative studies regarding which method is superior are controversial.Our aim is to compare ORIF and ExFix and clarify which method is better in terms of reduction and union results and major complications.Methods:A computerized research of MEDLINE,EMBASE,Springer,and Cochrane Library (before December 2014) for studies of any design comparing ORIF and ExFix was conducted.Weighted mean difference (WMD),risk ratio (RR) and corresponding 95% confidence intervals (CI) were used for estimating the effects of the two methods.Statistical analyses were done using Review Manager Version 5.2.Results:Ten cohort studies and one randomized clinical trial were included in our ultimate analysis.And the analysis found no significant difference between the two methods in deep infection (p =0.13),reduction (p =0.11),clinical evaluation (p =0.82),post-traumatic arthrosis (p =0.87),and union time (p =0.35).Besides,ExFix group was found to have a higher rate of superficial infection (p =0.001),malunion (p =0.01) and nonunion (p =0.02),but have a lower risk of unplanned hardware removal (p =0.0002).Conclusions:We suggest that ORIF has a relatively lower incidence rate of superficial infection,malunion and nonunion,but a higher rate of unplanned hardware removal.No difference was found in deep infection,reduction,clinical evaluation,post-traumatic arthrosis and union time.

  5. Glycaemic Control and Associated Self-Management Behaviours in Diabetic Outpatients: A Hospital Based Observation Study in Lusaka, Zambia

    Directory of Open Access Journals (Sweden)

    Emmanuel Mwila Musenge

    2016-01-01

    Full Text Available Background. The control of diabetes mellitus depends on several factors that also include individual lifestyles. We assessed glycaemic control status and self-management behaviours that may influence glycaemic control among diabetic outpatients. Methods. This cross-sectional study among 198 consenting randomly selected patients was conducted at the University Teaching Hospital diabetic clinic between September and December 2013 in Lusaka, Zambia. A structured interview schedule was used to collect data on demographic characteristics, self-management behaviours, and laboratory measurements. Binary logistic regression analysis using IBM SPSS for Windows version 20.0 was carried out to predict behaviours that were associated with glycaemic control status. Results. The proportion of patients that had good glycaemic control status (HbA1c≤ 48 mmol/mol was 38.7% compared to 61.3% that had poor glycaemic control status (HbA1c≥ 49 mmol/mol. Adherence to antidiabetic treatment and fasting plasma glucose predicted glycaemic control status of the patients. However, self-blood glucose monitoring, self-blood glucose monitoring means and exercise did not predict glycaemic control status of the patients.  Conclusion. We find evidence of poor glycaemic control status among most diabetic patients suggesting that health promotion messages need to take into account both individual and community factors to promote behaviours likely to reduce nonadherence.

  6. Erythropoietin has an anti-myeloma effect - a hypothesis based on a clinical observation supported by animal studies.

    Science.gov (United States)

    Mittelman, Moshe; Zeidman, Aliza; Kanter, Pazit; Katz, Odelia; Oster, Howard; Rund, Debbora; Neumann, Drorit

    2004-03-01

    Recombinant human erythropoietin (rHuEpo) was introduced into clinical practice more than a decade ago, and has been found to be effective in the treatment of several types of anemia, including anemia of end-stage renal failure and cancer-related anemia. No study has suggested that Epo might have an effect on the biology of the disease, nor any survival advantage to cancer patients treated with Epo for anemia has been reported. Here we report six patients with advanced multiple myeloma (MM) with very poor prognostic features, whose expected survival was cells. We then presented evidence that the mechanism is a new immune-mediated phenomenon, via activation of CD8+ T cells. Furthermore, evidence from the literature supports the antineoplastic effect of Epo. Epo might be used as an adjunct immune treatment in various malignant diseases, in addition to the current regimens and chemotherapeutic protocols. Future trials should determine the role of Epo in myeloma and cancer treatment, besides clarifying concerns about the presence of Epo receptors on some tumor cells.

  7. Primary nocturnal enuresis as a risk factor for sleep disorders: an observational questionnaire-based multicenter study

    Directory of Open Access Journals (Sweden)

    Esposito M

    2013-03-01

    Full Text Available Maria Esposito,1 Beatrice Gallai,2 Lucia Parisi,3 Michele Roccella,3 Rosa Marotta,4 Serena Marianna Lavano,4 Giovanni Mazzotta,5 Marco Carotenuto11Center for Childhood Headache, Clinic of Child and Adolescent Neuropsychiatry, Department of Mental Health, Physical and Preventive Medicine, Second University of Naples, Naples, Italy; 2Unit of Child and Adolescent Neuropsychiatry, University of Perugia, Perugia, Italy; 3Child Neuropsychiatry, Department of Psychology, University of Palermo, Palermo, Italy; 4Department of Psychiatry, “Magna Graecia” University of Catanzaro, Catanzaro, Italy; 5Unit of Child and Adolescent Neuropsychiatry, AUSL Umbria 2, Terni, ItalyIntroduction: Primary nocturnal enuresis (PNE is a common problem in developmental age with an estimated overall prevalence ranging from 1.6% to 15%, and possible persistence during adolescence. There is a growing interest in the sleep habits of children affected by PNE, which is derived from the contradictory data present in clinical literature. The aim of the present study was to evaluate the presence of sleep disturbances in a population of children affected by PNE, and to identify whether PNE could be considered as a risk factor for sleep disturbances among children.Materials and methods: A total of 190 PNE children (97 males, 93 females aged 7–15 years, (mean 9.64 ± 1.35 years, and 766 typically developing children matched for age (P = 0.131 and gender (P = 0.963 were enrolled. To evaluate the presence of sleep habits and disturbances, all of the subjects’ mothers filled out the Sleep Disturbances Scale for Children (SDSC, a questionnaire consisting of six subscales: Disorders in Initiating and Maintaining Sleep (DIMS, Sleep Breathing Disorders (SBD, Disorders of Arousal (DA, Sleep–Wake Transition Disorders (SWTD, Disorders of Excessive Somnolence (DOES, and Nocturnal Hyperhidrosis (SHY. The results were divided into “pathological” and “normal” scores using a cut

  8. The safety and efficacy of EGF-based cream for the prevention of radiotherapy-induced skin injury: results from a multicenter observational study

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Hyun Cheol [Dept.of Radiation Oncology, Seoul National University College of Medicine, Seoul (Korea, Republic of); Ahn, Seung Do [Dept.of Radiation Oncology, Asan Medical Center, Seoul (Korea, Republic of); Choi, Doo Ho [Dept.of Radiation Oncology, Samsung Medical Center, Seoul (Korea, Republic of); Kang, Min Kyu [Dept.of Radiation Oncology, eungnam University College of Medicine, Daegu (Korea, Republic of); Wu, Hong Gyun [Dept.of Radiation Oncology, Chonnam National University Hwasun Hospital, Huasun (Korea, Republic of)

    2014-09-15

    This study was designed to evaluate the efficacy and safety of topically applied recombinant human epidermal growth factor (rhEGF) for the prevention of radiation-induced dermatitis in cancer patients. From December 2010 to April 2012, a total of 1,172 cancer patients who received radiotherapy (RT) of more than 50 Gy were prospectively enrolled and treated with EGF-based cream. An acute skin reaction classified according to the Radiation Therapy Oncology Group 6-point rating scale was the primary end point and we also assessed the occurrence of edema, dry skin, or pruritus. The percentage of radiation dermatitis with maximum grade 0 and grade 1 was 19% and 58% at the time of 50 Gy, and it became 29% and 47% after completion of planned RT. This increment was observed only in breast cancer patients (from 18%/62% to 32%/49%). Adverse events related to the EGF-based cream developed in 49 patients (4%) with mild erythema the most common. Skin toxicity grade >2 was observed in 5% of the patients. Edema, dry skin, and pruritus grade > or =3 developed in 9%, 9%, and 1% of the patients, respectively. Prophylactic use of an EGF-based cream is effective in preventing radiation dermatitis with tolerable toxicity. Further studies comparing EGF cream with other topical agents may be necessary.

  9. Observer-Based Fuel Control Using Oxygen Measurement. A study based on a first-principles model of a pulverized coal fired Benson Boiler

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, Palle; Bendtsen, Jan Dimon; Mortensen, Jan Henrik; Just Nielsen, Rene; Soendergaard Pedersen, Tom [Aalborg Univ. (Denmark). Dept. of Control Engineering

    2005-01-01

    This report describes an attempt to improve the existing control of coal mills used at the Danish power plant Nordjyllandsvaerket Unit 3. The coal mills pulverize raw coal to a fine-grained powder, which is injected into the furnace of the power plant. In the furnace the coal is combusted, producing heat, which is used for steam production. With better control of the coal mills, the power plant can be controlled more efficiently during load changes, thus improving the overall availability and efficiency of the plant. One of the main difficulties from a control point of view is that the coal mills are not equipped with sensors that detect how much coal is injected into the furnace. During the project, a fairly detailed, non-linear differential equation model of the furnace and the steam circuit was constructed and validated against data obtained at the plant. It was observed that this model was able to capture most of the important dynamics found in the data. Based on this model, it is possible to extract linearized models in various operating points. The report discusses this approach and illustrates how the model can be linearized and reduced to a lower-order linear model that is valid in the vicinity of an operating point by removing states that have little influence on the overall response. A viable adaptive control strategy would then be to design controllers for each of these simplified linear models, i.e., the control loop that sets references to the coal mills and feedwater, and use the load as a separate input to the control. The control gains should then be scheduled according to the load. However, the variations and uncertainties in the coal mill are not addressed directly in this approach. Another control approach was taken in this project, where a Kalman filter based on measurements of air flow blown into the furnace and the oxygen concentration in the flue gas is designed to estimate the actual coal flow injected into the furnace. With this estimate

  10. Ground-based observations of exoplanet atmospheres

    NARCIS (Netherlands)

    Mooij, Ernst Johan Walter de

    2011-01-01

    This thesis focuses on the properties of exoplanet atmospheres. The results for ground-based near-infrared secondary eclipse observations of three different exoplanets, TrES-3b, HAT-P-1b and WASP-33b, are presented which have been obtained with ground-based telescopes as part of the GROUSE project.

  11. Does lumbar spinal degeneration begin with the anterior structures? A study of the observed epidemiology in a community-based population

    Directory of Open Access Journals (Sweden)

    Jarvik Jeffrey G

    2011-09-01

    Full Text Available Abstract Background- Prior studies that have concluded that disk degeneration uniformly precedes facet degeneration have been based on convenience samples of individuals with low back pain. We conducted a study to examine whether the view that spinal degeneration begins with the anterior spinal structures is supported by epidemiologic observations of degeneration in a community-based population. Methods- 361 participants from the Framingham Heart Study were included in this study. The prevalences of anterior vertebral structure degeneration (disk height loss and posterior vertebral structure degeneration (facet joint osteoarthritis were characterized by CT imaging. The cohort was divided into the structural subgroups of participants with 1 no degeneration, 2 isolated anterior degeneration (without posterior degeneration, 3 combined anterior and posterior degeneration, and 4 isolated posterior degeneration (without anterior structure degeneration. We determined the prevalence of each degeneration pattern by age group Results- As the prevalence of the no degeneration and isolated anterior degeneration patterns decreased with increasing age group, the prevalence of the combined anterior/posterior degeneration pattern increased. 22% of individuals demonstrated isolated posterior degeneration, without an increase in prevalence by age group. Isolated posterior degeneration was most common at the L5-S1 and L4-L5 spinal levels. In multivariate analyses, disk height loss was independently associated with facet joint osteoarthritis, as were increased age (years, female sex, and increased BMI (kg/m2, but not smoking. Conclusions- The observed epidemiology of lumbar spinal degeneration in the community-based population is consistent with an ordered progression beginning in the anterior structures, for the majority of individuals. However, some individuals demonstrate atypical patterns of degeneration, beginning in the posterior joints. Increased age and BMI

  12. Linkage to and engagement in HIV care in western Kenya: An observational study using population-based estimates from home-based counseling and testing

    Science.gov (United States)

    Genberg, Becky L.; Naanyu, Violet; Wachira, Juddy; Hogan, Joseph W.; Sang, Edwin; Nyambura, Monicah; Odawa, Michael; Duefield, Corey; Ndege, Samson; Braitstein, Paula

    2015-01-01

    Summary Background There is limited research characterizing the HIV care continuum with population-based data in sub-Saharan Africa. The objectives of this study were to: 1) describe engagement in care among all known HIV-positive adults in one sub-county of western Kenya; and 2) determine the time to and predictors of linkage and engagement among adults newly diagnosed via home-based counseling and testing (HBCT). Methods AMPATH (Academic Model Providing Access to Healthcare) has provided HIV care in western Kenya since 2001 and HBCT since 2007. Following a widespread HBCT program in Bunyala sub-county, electronic medical records (EMR) were reviewed to identify uptake of care among individuals with previously known (self-reported) infection and new (identified by HBCT) HIV diagnoses as of June 2014. Engagement in HIV care was defined as an initial encounter with an HIV care provider. Cox regression analysis was used to examine the predictors of engagement among those newly diagnosed. Findings Of the 3,482 infected adults identified, 61% had previously known infections, among whom 84% (n = 1778/2122) had ever had at least one clinical encounter within AMPATH. While 73% were registered in the EMR, only 15% (n = 209/1360) of the newly diagnosed had seen a clinician over a median of 3·4 years. The median time to engagement among the newly diagnosed was 60 days (interquartile range: 10–411 days). Interpretation Engagement in care was high among those who at the time of HBCT were already known HIV-positive, but few who were newly diagnosed in HBCT saw an HIV care provider. Funding This research was supported by the President’s Emergency Plan for AIDS Relief (PEPFAR) through USAID under the terms of Cooperative Agreement No. AID-623-A-12-0001. The HBCT program was supported by grants from Abbott Laboratories, the Purple ville Foundation, and the Global Business Coalition. Abbott Laboratories provided test kits and logistical support. Further support was provided by

  13. UFOs: Observations, Studies and Extrapolations

    CERN Document Server

    Baer, T; Barnes, M J; Bartmann, W; Bracco, C; Carlier, E; Cerutti, F; Dehning, B; Ducimetière, L; Ferrari, A; Ferro-Luzzi, M; Garrel, N; Gerardin, A; Goddard, B; Holzer, E B; Jackson, S; Jimenez, J M; Kain, V; Zimmermann, F; Lechner, A; Mertens, V; Misiowiec, M; Nebot Del Busto, E; Morón Ballester, R; Norderhaug Drosdal, L; Nordt, A; Papotti, G; Redaelli, S; Uythoven, J; Velghe, B; Vlachoudis, V; Wenninger, J; Zamantzas, C; Zerlauth, M; Fuster Martinez, N

    2012-01-01

    UFOs (“ Unidentified Falling Objects”) could be one of the major performance limitations for nominal LHC operation. Therefore, in 2011, the diagnostics for UFO events were significantly improved, dedicated experiments and measurements in the LHC and in the laboratory were made and complemented by FLUKA simulations and theoretical studies. The state of knowledge is summarized and extrapolations for LHC operation in 2012 and beyond are presented. Mitigation strategies are proposed and related tests and measures for 2012 are specified.

  14. An observational study of excellence in science teaching based on a sample of outstanding science teachers: Methods of teaching excellence in science

    Science.gov (United States)

    Mazmanian, Victor

    The aim of this study was to document the teaching and learning strategies utilized by a group of science teachers, who were recipients of the Presidential Awards for Excellence in Science and Math Teaching (PAESMT). Six science teachers were observed in their classrooms while they were teaching. Thirty-six lessons were analyzed using a framework of categories of analysis to determine the special traits and common exceptional methods that these teachers had. The findings confirmed the ones predicted by theoretical frameworks of cognitive science and current models of constructivism in teaching. The results of the study supported the importance of the role of the teacher as an active agent in construction of knowledge while also providing sufficient student freedom of exploration and self-realization as needed to grow intellectually and develop skills in metacognition (e.g., reflective critical thought, and learning how to learn). Further, the analyses revealed the complementarity between the teacher's methodology and the processes of student cognition. Some misconceptions that commonly appeared among the observed science students were also documented. The study also explored possible methods to rectify these misconceptions, based in part on prior publications and also on observations of the PAESMT teachers' strategies. The results of this study showed the unique methods of teaching employed by PAESMT recipients to an extent that reached beyond the results of previous research, which published traits and characteristics of such teachers. This study determined the common traits among these teachers and identified their common methods of teaching science. The teacher's role as a facilitator was documented repeatedly among these award-winning teachers and was determined to be an integral tool for the students' successful knowledge construction and development of accurate scientific ways of thinking.

  15. A model of scientific attitudes assessment by observation in physics learning based scientific approach: case study of dynamic fluid topic in high school

    Science.gov (United States)

    Yusliana Ekawati, Elvin

    2017-01-01

    This study aimed to produce a model of scientific attitude assessment in terms of the observations for physics learning based scientific approach (case study of dynamic fluid topic in high school). Development of instruments in this study adaptation of the Plomp model, the procedure includes the initial investigation, design, construction, testing, evaluation and revision. The test is done in Surakarta, so that the data obtained are analyzed using Aiken formula to determine the validity of the content of the instrument, Cronbach’s alpha to determine the reliability of the instrument, and construct validity using confirmatory factor analysis with LISREL 8.50 program. The results of this research were conceptual models, instruments and guidelines on scientific attitudes assessment by observation. The construct assessment instruments include components of curiosity, objectivity, suspended judgment, open-mindedness, honesty and perseverance. The construct validity of instruments has been qualified (rated load factor > 0.3). The reliability of the model is quite good with the Alpha value 0.899 (> 0.7). The test showed that the model fits the theoretical models are supported by empirical data, namely p-value 0.315 (≥ 0.05), RMSEA 0.027 (≤ 0.08)

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

    Science.gov (United States)

    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

  17. Earth Observation-Based Dwelling Detection Approaches in a Highly Complex Refugee Camp Environment — A Comparative Study

    Directory of Open Access Journals (Sweden)

    Kristin Spröhnle

    2014-09-01

    Full Text Available For effective management of refugee camps or camps for internally displaced persons (IDPs relief organizations need up-to-date information on the camp situation. In cases where detailed field assessments are not available, Earth observation (EO data can provide important information to get a better overview about the general situation on the ground. In this study, different approaches for dwelling detection were tested using the example of a highly complex camp site in Somalia. On the basis of GeoEye-1 imagery, semi-automatic object-based and manual image analysis approaches were applied, compared and evaluated regarding their analysis results (absolute numbers, population estimation, spatial pattern, statistical correlations and production time. Although even the results of the visual image interpretation vary considerably between the interpreters, there is a similar pattern resulting from all methods, which shows same tendencies for dense and sparse populated areas. The statistical analyses revealed that all approaches have problems in the more complex areas, whereas there is a higher variance in manual interpretations with increasing complexity. The application of advanced rule sets in an object-based environment allowed a more consistent feature extraction in the area under investigation that can be obtained at a fraction of the time compared to visual image interpretation if large areas have to be observed.

  18. Assessing observational studies of medical treatments

    Directory of Open Access Journals (Sweden)

    Butani Yogita

    2005-09-01

    Full Text Available Abstract 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.

  19. Aerosols optical properties in dynamic atmosphere in the northwestern part of the Indian Himalaya: A comparative study from ground and satellite based observations

    Science.gov (United States)

    Guleria, Raj Paul; Kuniyal, Jagdish Chandra; Rawat, Pan Singh; Thakur, Harinder Kumar; Sharma, Manum; Sharma, Nand Lal; Singh, Mahavir; Chand, Kesar; Sharma, Priyanka; Thakur, Ajay Kumar; Dhyani, Pitamber Prasad; Bhuyan, Pradip Kumar

    2011-08-01

    The present study deals with the aerosol optical property which carried out during April 2006 to March 2007 over Mohal (31.9°N, 77.12°E) in the northwestern Indian Himalaya. The study was conducted using ground based Multi-wavelength Radiometer (MWR) and Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. The daily average aerosol optical depth (AOD) at 500 nm was found to be (mean ± standard deviation) 0.24 ± 0.10. The afternoon AOD values have been noticed to be higher than the forenoon AOD values. Spectral AOD values exhibited larger day-to-day variation in finer aerosols during the observation period. The daily average value of Ångström exponent 'α' and turbidity coefficient 'β' obtained was 1.10 ± 0.38 and 0.12 ± 0.08 respectively. Higher value of AOD ~ 0.39 ± 0.06 during summer associated with low α ~ 0.73 ± 0.28 has attributed to the increase in the relative dominance of coarse size particles. In winter α ~ 1.21 ± 0.32 indicating a considerable increase in fine size particles, attributed to the anthropogenic activities. The AOD spectra seem to be more wavelength dependent in winter as compared to summer. Comparison of MWR observation with MODIS observation indicates a good conformity between ground-based and satellite derived AOD. The root mean square deviation (RMSD), mean absolute bias deviation (MABD) and correlation coefficient have been found to be ~ 0.08, ~ 0.06 and ~ 0.77 respectively. These results suggest that the AOD retrieval through satellite can be able to characterize AOD distribution over Mohal. However, further efforts to eliminate systematic errors in the existing MODIS products are needed. During the observation period ~ 30%, ~ 47% and ~ 62% air parcels drawn at 4000, 5500 and 8000 m above ground level respectively reached at Mohal which passed through or originated from The Great Sahara. The maximum AOD at 500 nm occurred on 8 May 2006. This has caused a significant reduction in surface reaching solar irradiance by

  20. Neural network-based estimates of Southern Ocean net community production from in-situ O2 / Ar and satellite observation: a methodological study

    Directory of Open Access Journals (Sweden)

    C.-H. Chang

    2013-10-01

    Full Text Available Southern Ocean organic carbon export plays an important role in the global carbon cycle, yet its basin-scale climatology and variability are uncertain due to limited coverage of in situ observations. In this study, a neural network approach based on the self-organizing map (SOM is adopted to construct weekly gridded (1° × 1° maps of organic carbon export for the Southern Ocean from 1998 to 2009. The SOM is trained with in situ measurements of O2 / Ar-derived net community production (NCP that are tightly linked to the carbon export in the mixed layer on timescales of 1–2 weeks, and six potential NCP predictors: photosynthetically available radiation (PAR, particulate organic carbon (POC, chlorophyll (Chl, sea surface temperature (SST, sea surface height (SSH, and mixed layer depth (MLD. This non-parametric approach is based entirely on the observed statistical relationships between NCP and the predictors, and therefore is strongly constrained by observations. A thorough cross-validation yields three retained NCP predictors, Chl, PAR, and MLD. Our constructed NCP is further validated by good agreement with previously published independent in situ derived NCP of weekly or longer temporal resolution through real-time and climatological comparisons at various sampling sites. The resulting November–March NCP climatology reveals a pronounced zonal band of high NCP roughly following the subtropical front in the Atlantic, Indian and western Pacific sectors, and turns southeastward shortly after the dateline. Other regions of elevated NCP include the upwelling zones off Chile and Namibia, Patagonian Shelf, Antarctic coast, and areas surrounding the Islands of Kerguelen, South Georgia, and Crozet. This basin-scale NCP climatology closely resembles that of the satellite POC field and observed air-sea CO2 flux. The long-term mean area-integrated NCP south of 50° S from our dataset, 14 mmol C m–2 d–1, falls within the range of 8.3–24 mmol C m

  1. Observation of an Aligned Gas - Solid "Eutectic" during Controlled Directional Solidification Aboard the International Space Station - Comparison with Ground-based Studies

    Science.gov (United States)

    Grugel, R. N.; Anilkumar, A.

    2005-01-01

    Direct observation of the controlled melting and solidification of succinonitrile was conducted in the glovebox facility of the International Space Station (ISS). The experimental samples were prepared on ground by filling glass tubes, 1 cm ID and approximately 30 cm in length, with pure succinonitrile (SCN) in an atmosphere of nitrogen at 450 millibar pressure for eventual processing in the Pore Formation and Mobility Investigation (PFMI) apparatus in the glovebox facility (GBX) on board the ISS. Real time visualization during controlled directional melt back of the sample showed nitrogen bubbles emerging from the interface and moving through the liquid up the imposed temperature gradient. Over a period of time these bubbles disappear by dissolving into the melt. Translation is stopped after melting back of about 9 cm of the sample, with an equilibrium solid-liquid interface established. During controlled re-solidification, aligned tubes of gas were seen growing perpendicular to the planar solid/liquid interface, inferring that the nitrogen previously dissolved into the liquid SCN was now coming out at the solid/liquid interface and forming the little studied liquid = solid + gas eutectic-type reaction. The observed structure is evaluated in terms of spacing dimensions, interface undercooling, and mechanisms for spacing adjustments. Finally, the significance of processing in a microgravity environment is ascertained in view of ground-based results.

  2. A Complex Multiherbal Regimen Based on Ayurveda Medicine for the Management of Hepatic Cirrhosis Complicated by Ascites: Nonrandomized, Uncontrolled, Single Group, Open-Label Observational Clinical Study

    Directory of Open Access Journals (Sweden)

    Manish V. Patel

    2015-01-01

    Full Text Available Hepatic cirrhosis is one of the leading causes of death worldwide, especially if complicated by ascites. This chronic condition can be related to the classical disease entity jalodara in Traditional Indian Medicine (Ayurveda. The present paper aims to evaluate the general potential of Ayurvedic therapy for overall clinical outcomes in hepatic cirrhosis complicated by ascites (HCcA. In form of a nonrandomized, uncontrolled, single group, open-label observational clinical study, 56 patients fulfilling standardized diagnostic criteria for HCcA were observed during their treatment at the P. D. Patel Ayurveda Hospital, Nadiad, India. Based on Ayurvedic tradition, a standardized treatment protocol was developed and implemented, consisting of oral administration of single and compound herbal preparations combined with purificatory measures as well as dietary and lifestyle regimens. The outcomes were assessed by measuring liver functions through specific clinical features and laboratory parameters and by evaluating the Child-Pugh prognostic grade score. After 6 weeks of treatment and a follow-up period of 18 weeks, the outcomes showed statistically significant and clinically relevant improvements. Further larger and randomized trials on effectiveness, safety, and quality of the Ayurvedic approach in the treatment of HCcA are warranted to support these preliminary findings.

  3. A Complex Multiherbal Regimen Based on Ayurveda Medicine for the Management of Hepatic Cirrhosis Complicated by Ascites: Nonrandomized, Uncontrolled, Single Group, Open-Label Observational Clinical Study.

    Science.gov (United States)

    Patel, Manish V; Patel, Kalapi B; Gupta, Shivenarain; Michalsen, Andreas; Stapelfeldt, Elmar; Kessler, Christian S

    2015-01-01

    Hepatic cirrhosis is one of the leading causes of death worldwide, especially if complicated by ascites. This chronic condition can be related to the classical disease entity jalodara in Traditional Indian Medicine (Ayurveda). The present paper aims to evaluate the general potential of Ayurvedic therapy for overall clinical outcomes in hepatic cirrhosis complicated by ascites (HCcA). In form of a nonrandomized, uncontrolled, single group, open-label observational clinical study, 56 patients fulfilling standardized diagnostic criteria for HCcA were observed during their treatment at the P. D. Patel Ayurveda Hospital, Nadiad, India. Based on Ayurvedic tradition, a standardized treatment protocol was developed and implemented, consisting of oral administration of single and compound herbal preparations combined with purificatory measures as well as dietary and lifestyle regimens. The outcomes were assessed by measuring liver functions through specific clinical features and laboratory parameters and by evaluating the Child-Pugh prognostic grade score. After 6 weeks of treatment and a follow-up period of 18 weeks, the outcomes showed statistically significant and clinically relevant improvements. Further larger and randomized trials on effectiveness, safety, and quality of the Ayurvedic approach in the treatment of HCcA are warranted to support these preliminary findings.

  4. In-vehicle and site-based observations of vehicles and cyclists : a small-scale ND study in The Netherlands. PROmoting real Life Observations for Gaining Understanding of road user behaviour in Europe PROLOGUE, Deliverable D3.4

    NARCIS (Netherlands)

    Christoph, M. Nes, N. van Pauwelussen, J. Mansvelders, R. Horst, A.R.A. van der & Hoedemaeker, M.

    2011-01-01

    The main objective of the project PROLOGUE (PROmoting real Life Observations for Gaining Understanding of road user behaviour in Europe) is to explore the feasibility and usefulness of a large-scale European naturalistic driving observation study. The work described in this deliverable focused on th

  5. Family-based study of HTR2A in suicide attempts: observed gene, gene × environment and parent-of-origin associations.

    Science.gov (United States)

    Ben-Efraim, Y J; Wasserman, D; Wasserman, J; Sokolowski, M

    2013-07-01

    While suicidal behavior is frequently accompanied by serotonergic system alterations, specific associations with genetic variation in the serotonin 2A receptor (HTR2A) gene have been inconsistent. Using a family-based study design of 660 offspring who have made a suicide attempt (SA) and both parents, we conducted an association and linkage analysis using single-nucleotide polymorphisms (SNPs) with extensive gene coverage, and included the study of parent-of-origin (POE) and gene-environment interaction (G × E), also using previously unstudied exposures. The main finding was a G × E between the exon 1 SNP rs6313 and exposure to cumulative types of lifetime stressful life events (SLEs), driven by overtransmission of CT and undertransmission of TT, both in relation to other genotypes. Further exploratory analysis revealed a significant POE in this G × E in female subjects, which followed a polar overdominant inheritance pattern. In addition, rs6310 and rs6305 were found to significantly associate with SA in the total sample. A G × E in female subjects (rs7322347 × physical assault in childhood/adolescence) confirmed features of a previously observed association with SA. Other potentially interesting nominally significant findings were observed, but like the G × E of rs7322347 did not pass a false-discovery rate cutoff. Taken together, this study found multiple associations of HTR2A SNPs on SA, with strongest statistical evidence for a G × E involving rs6313, and further suggested the importance of taking into account different inheritance patterns and G × Es with regard to HTR2A.

  6. Evidence-based obstetrics in four hospitals in China: An observational study to explore clinical practice, women's preferences and provider's views

    Directory of Open Access Journals (Sweden)

    Liang Ji

    2001-05-01

    Full Text Available Abstract Background Evidence-based obstetric care is widely promoted in developing countries, but the success of implementation is not known. Using selected childbirth care procedures in four hospitals in Shanghai, we compared practice against evidence-based information, and explored user and provider views about each procedure. Methods Observational study. Using the Cochrane Library, we identified six procedures that should be avoided as routine and two that should be encouraged. Procedure rate determined by exit interviews with women, verified using hospital notes. Views of women and providers explored with in depth interviews. The study sites were three hospitals in Shanghai and one in neighbouring province of Jiangsu. 150 women at each centre for procedure rate, and 48 in-depth interviews with women and providers. Results Vaginal births were 50% (303/599 of the total. Of the six practices where evidence suggests they should be avoided as routine, three were performed with rates above 70%: pubic shaving (3 hospitals, rectal examination (3 hospitals, and episiotomy (3 hospitals. Most women delivered lying down, pain relief was rarely given, and only in the urban district hospital did women routinely have a companion. Most women wanted support or companionship during labour and to be given pain relief; but current practice is insufficient to meet women's needs. Conclusion Obstetric practice is not following best available evidence in the hospitals studied. There is a need to adjust hospital policy to support the use of interventions proven to be of benefit to women during childbirth, and develop approaches that ensure clinical practice changes.

  7. In-vehicle and site-based observations of vehicles and cyclists. A small-scale ND study in the Netherlands. PROLOGUE Deliverable D3.4

    NARCIS (Netherlands)

    Christoph, M.; Nes, N. van; Pauwelussen, J.J.A.; Mansvelders, R.; Horst, A.R.A. van der; Hoedemaeker, D.M.

    2010-01-01

    The main objective of the project PROLOGUE (PROmoting real Life Observations for Gaining Understanding of road user behaviour in Europe) is to explore the feasibility and usefulness of a large-scale European naturalistic driving observation study. The work described in this deliverable focused on th

  8. Confounding in publications of observational intervention studies

    NARCIS (Netherlands)

    Groenwold, Rolf H. H.; Hoes, Arno W.; Hak, Eelko

    2007-01-01

    We conducted a systematic literature search in Medline to assess the proportion of observational intervention studies appreciating confounding bias in peer-reviewed medical literature from 1985 through 2005. This study shows only 9% of all papers on observational intervention studies published in pe

  9. Fuzzy model-based observers for fault detection in CSTR.

    Science.gov (United States)

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

    2015-11-01

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

  10. Burden of herpes zoster and postherpetic neuralgia in Japanese adults 60 years of age or older: Results from an observational, prospective, physician practice-based cohort study.

    Science.gov (United States)

    Sato, Keiko; Adachi, Koichi; Nakamura, Hiroyuki; Asano, Kazuhiro; Watanabe, Akihiro; Adachi, Riri; Kiuchi, Mariko; Kobayashi, Keiju; Matsuki, Taizo; Kaise, Toshihiko; Gopala, Kusuma; Holl, Katsiaryna

    2016-12-05

    Approximately one in three persons will develop herpes zoster during their lifetime, and it can lead to serious complications such as postherpetic neuralgia. However, evidence on burden of herpes zoster and postherpetic neuralgia in Japan is limited. This prospective, observational, multicenter, physician practice-based cohort study was conducted in Kushiro, Hokkaido, Japan (Clinicaltrials.gov identifier NCT01873365) to assess the incidence and hospitalization rates of herpes zoster, and the proportion, clinical burden and risk factors for postherpetic neuralgia in adults aged 60 years or more. Within the study area, 800 subjects developed herpes zoster and 412 were eligible for the study. Herpes zoster incidence was 10.2/1000 person-years and higher among women and older subjects. Subjects with herpes zoster required on average 5.7 outpatient consultations. Herpes zoster-associated hospitalization rate was 3.4% (27/800). The proportion of postherpetic neuralgia and other complications was 9.2% (38/412) and 26.5% (109/412), respectively. Statistically significant association with the development of postherpetic neuralgia was male sex (odds ratio [OR], 2.51; 95% confidence interval [CI], 1.17-5.38), age of 70-74 years (OR, 3.51; 95% CI, 1.09-11.3), immunosuppressive therapy (OR, 6.44; 95% CI, 1.26-32.9), severe herpes zoster pain at first consultation (OR, 3.08; 95% CI, 1.10-8.62) and rash on upper arms (vs no rash on upper arms; OR, 3.46; 95% CI, 1.10-10.9). Considerable herpes zoster and postherpetic neuralgia burden exists among elderly in Japan, and there may be predictive factors at the first visit which could be indicative of the risk of developing postherpetic neuralgia.

  11. Burden and outcomes of pressure ulcers in cancer patients receiving the Kerala model of home based palliative care in India: Results from a prospective observational study

    Directory of Open Access Journals (Sweden)

    Biji M Sankaran

    2015-01-01

    Full Text Available Aim: To report the prevalence and outcomes of pressure ulcers (PU seen in a cohort of cancer patients requiring home-based palliative care. Materials and Methods: All patients referred for home care were eligible for this prospective observational study, provided they were living within a distance of 35 km from the institute and gave informed consent. During each visit, caregivers were trained and educated for providing nursing care for the patient. Dressing material for PU care was provided to all patients free of cost and care methods were demonstrated. Factors influencing the occurrence and healing of PUs were analyzed using logistic regression. Duration for healing of PU was calculated using the Kaplan Meier method. P < 0.05 are taken as significant. Results: Twenty-one of 108 (19.4% enrolled patients had PU at the start of homecare services. None of the patients developed new PU during the course of home care. Complete healing of PU was seen in 9 (42.9% patients. The median duration for healing of PU was found to be 56 days. Median expenditure incurred in patients with PU was Rs. 2323.40 with a median daily expenditure of Rs. 77.56. Conclusions: The present model of homecare service delivery was found to be effective in the prevention and management of PUs. The high prevalence of PU in this cohort indicates a need for greater awareness for this complication. Clinical Trial Registry Number: CTRI/2014/03/004477

  12. Effect of eprosartan-based therapy on systolic blood pressure and total cardiovascular risk in a large international population: preliminary report of the observational POWER study

    Directory of Open Access Journals (Sweden)

    Goudev A

    2012-09-01

    Full Text Available Assen Goudev,1 Jean-Pascal Berrou,2 Atul Pathak3 On behalf of the POWER Investigators1Department of Cardiology, Queen Giovanna University Hospital, Sofia, Bulgaria; 2Strategic Medical Affairs, CardioMetabolic Established Products, Abbott Products Operations AG, Allschwil, Switzerland; 3Faculte´ de Médecine et CHU Toulouse, Unité de Pharmacologie Cardiovasculaire et Autonome, Service de Pharmacologie et Cardiologie, INSERM U 1048, Université Paul Sabatier, Toulouse, FranceBackground: Estimation of total cardiovascular risk is useful for developing preventive strategies for individual patients. The POWER (Physicians' Observational Work on Patient Education According to their Vascular Risk survey, a 6-month, open-label, multinational, post-marketing observational evaluation of eprosartan, an angiotensin II receptor blocker, was undertaken to assess the efficacy and safety of eprosartan-based therapy in the treatment of high arterial blood pressure in a large population recruited from 16 countries with varying degrees of baseline cardiovascular risk, and the effect of eprosartan-based therapy on total cardiovascular risk, as represented by the SCORE® (Systematic Coronary Risk Assessment or Framingham risk equations.Methods: Participating physicians recruited > 29,000 hypertensive patients whom they considered to be candidates (according to specified criteria for treatment with eprosartan 600 mg/day, with other drugs added at the discretion of the physician.Results: During treatment, systolic blood pressure decreased by 25.8 ± 14.4 mmHg to 134.6 ± 11.4 mmHg (P < 0.001, mean diastolic blood pressure fell by 12.6 ± 9.5 mmHg to 81.1 ± 7.6 mmHg, and pulse pressure fell by 13.2 ± 13.5 mmHg to 53.6 ± 11.4 mmHg (both P < 0.01. Calculated total cardiovascular risk declined in parallel with the reduction in blood pressure.Conclusion: The POWER study has demonstrated, in a large and nonselected population, the feasibility and practicability of

  13. An Observer-Based Foundation of Geometry

    Science.gov (United States)

    Bahreyni, Newshaw; Knuth, Kevin H.

    2012-02-01

    The fact that some events influence other events enables one to define a partially ordered set (poset) of events, often referred to as a causal set. A chain of events, called observer chain, can be quantified by labeling its events numerically. Other events in a poset may be quantified with respect to an observer chain/chains by projecting them onto the chain, resulting in a pair of numbers. Similarly, pairs of events, called intervals, can be quantified with four numbers. Under certain conditions, this leads to the Minkowski metric, Lorentz transformations and the mathematics of special relativity (Bahreyni & Knuth, APS March Meeting 2011). We exploit the same techniques to demonstrate that geometric concepts can be derived from order-theoretic concepts. We show how chains in a poset can be used to define points and line segments. Subsequent quantification results in the Pythagorean Theorem and the inner product as well as other geometric concepts and measures. Thus the geometry of space, which is assumed to be fundamental, emerges as a result of quantifying a partially ordered set. More importantly, this proposed foundation of geometry is entirely observer-based, which may provide a natural way toward integration with quantum mechanics.

  14. Reduced order observer based identification of base isolated buildings

    Institute of Scientific and Technical Information of China (English)

    Satish Nagarajaiah; Prasad Dharap

    2003-01-01

    The objective of this study is to identify system parameters from the recorded response of base isolated buildings, such as USC hospital building, during the 1994 Northridge earthquake. Full state measurements are not available for identification. Additionally, the response is nonlinear due to the yielding of the lead-rubber bearings. Two new approaches are presented in this paper to solve the aforementioned problems. First, a reduced order observer is used to estimate the unmeasured states. Second, a least squares technique with time segments is developed to identify the piece-wise linear system properties. The observer is used to estimate the initial conditions needed for the time segmented identification. A series of equivalent linear system parameters are identified in different time segments. It is shown that the change in system parameters, such as frequencies and damping ratios, due to nonlinear behavior of the lead-rubber bearings, are reliably estimated using the presented technique. It is shown that the response was reduced due to yielding of the lead-rubber bearings and period lengthening.

  15. STRengthening analytical thinking for observational studies

    DEFF Research Database (Denmark)

    Altman, Douglas G.; le Cessie, Saskia; Abrahamowicz, Michal

    2014-01-01

    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...

  16. Transport pathways of CO in the African upper troposphere during the monsoon season: a study based upon the assimilation of spaceborne observations

    Directory of Open Access Journals (Sweden)

    B. Barret

    2008-06-01

    Full Text Available The transport pathways of carbon monoxide (CO in the African Upper Troposphere (UT during the West African Monsoon (WAM is investigated through the assimilation of CO observations by the Aura Microwave Limb Sounder (MLS in the MOCAGE Chemistry Transport Model (CTM. The assimilation setup, based on a 3-D First Guess at Assimilation Time (3-D-FGAT variational method is described. Comparisons between the assimilated CO fields and in situ airborne observations from the MOZAIC program between Europe and both Southern Africa and Southeast Asia show an overall good agreement around the lowermost pressure level sampled by MLS (~215 hPa. The 4-D assimilated fields averaged over the month of July 2006 have been used to determine the main dynamical processes responsible for the transport of CO in the African UT. The studied period corresponds to the second AMMA (African Monsoon Multidisciplinary Analyses aircraft campaign. At 220 hPa, the CO distribution is characterized by a latitudinal maximum around 5° N mostly driven by convective uplift of air masses impacted by biomass burning from Southern Africa, uplifted within the WAM region and vented predominantly southward by the upper branch of the winter hemisphere Hadley cell. Above 150 hPa, the African CO distribution is characterized by a broad maximum over northern Africa. This maximum is mostly controlled by the large scale UT circulation driven by the Asian Summer Monsoon (ASM and characterized by the Asian Monsoon Anticyclone (AMA centered at 30° N and the Tropical Easterly Jet (TEJ on the southern flank of the anticyclone. Asian pollution uplifted to the UT over large region of Southeast Asia is trapped within the AMA and transported by the anticyclonic circulation over Northeast Africa. South of the AMA, the TEJ is responsible for the tranport of CO-enriched air masses from India and Southeast Asia over Africa. Using the high time resolution provided by the 4-D assimilated fields, we give evidence

  17. Classical method of coherence estimation based on mutual wavelet-spectra of time variations of studied processes observed in the Earth atmosphere

    Science.gov (United States)

    Fahrutdinova, Antonina; Rizhov, Dmitriy; Magdeev, Konstantin

    In the present article the authors offer to conduct a research into influence exerted by solar effects (Wolf number) on time variations of average monthly values of the zonal wind, obtained in Kazan Federal University with the help of a meteoric radar complex KGU-M5 within the mesosphere - lower thermosphere during the period from 1978 to 2007. There exists a wide variety of signal processing methods that can be used to identify connection between two processes. A classical method of coherence calculation based on a mutual wavelet-spectrum has become widely used. Due to limited duration of the studied time series of dynamic parameters we have found coherent structures of time variations in solar activity (Wolf number) and zonal wind within the mesosphere-lower thermosphere for the scales of about 0.5, 1, 1.5, 2, 3, and 4-5 years. SCM values have been calculated for the most pronounced periodicities observed for scales of about 3 years during the period from 1986 to 1997. The average SCM value was equal to 0.75. Confidence interval of obtained SCM values was in the range of [0.54, 0.88] for the significance level As the atmosphere is a non-linear medium, this can lead to shifting and broadening of spectral components. In addition to the above mentioned periodicities (0.5 - 5 years), a wavelet spectrum calculated in the zonal wind field indicates possible presence of time periodicities in the range of 11-20 years.

  18. Community Engagement in Observational Human Exposure Studies

    Science.gov (United States)

    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...

  19. Observing Protein & Energy Nutrition (OPEN) Study

    Science.gov (United States)

    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.

  20. Operational evapotranspiration based on Earth observation satellites

    Science.gov (United States)

    Gellens-Meulenberghs, Françoise; Ghilain, Nicolas; Arboleda, Alirio; Barrios, Jose-Miguel

    2016-04-01

    Geostationary satellites have the potential to follow fast evolving atmospheric and Earth surface phenomena such those related to cloud cover evolution and diurnal cycle. Since about 15 years, EUMETSAT has set up a network named 'Satellite Application Facility' (SAF, http://www.eumetsat.int/website/home/Satellites/GroundSegment/Safs/index.html) to complement its ground segment. The Land Surface Analysis (LSA) SAF (http://landsaf.meteo.pt/) is devoted to the development of operational products derived from the European meteorological satellites. In particular, an evapotranspiration (ET) product has been developed by the Royal Meteorological Institute of Belgium. Instantaneous and daily integrated results are produced in near real time and are freely available respectively since the end of 2009 and 2010. The products cover Europe, Africa and the Eastern part of South America with the spatial resolution of the SEVIRI sensor on-board Meteosat Second Generation (MSG) satellites. The ET product algorithm (Ghilain et al., 2011) is based on a simplified Soil-Vegetation-Atmosphere transfer (SVAT) scheme, forced with MSG derived radiative products (LSA SAF short and longwave surface fluxes, albedo). It has been extensively validated against in-situ validation data, mainly FLUXNET observations, demonstrating its good performances except in some arid or semi-arid areas. Research has then been pursued to develop an improved version for those areas. Solutions have been found in reviewing some of the model parameterizations and in assimilating additional satellite products (mainly vegetation indices and land surface temperature) into the model. The ET products will be complemented with related latent and sensible heat fluxes, to allow the monitoring of land surface energy partitioning. The new algorithm version should be tested in the LSA-SAF operational computer system in 2016 and results should become accessible to beta-users/regular users by the end of 2016/early 2017. In

  1. [The Strengthening the Reporting of Observational Studies in Epidemiology [STROBE] statement: guidelines for reporting observational studies

    DEFF Research Database (Denmark)

    Elm, E. von; Altman, D.G.; Egger, M.;

    2008-01-01

    Much biomedical research is observational. The reporting of such research is often inadequate, which hampers the assessment of its strengths and weaknesses and of a study's generalisability. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) initiative developed rec...

  2. Study of the opportunities of analytical determination of the origin-destination flows in roundabout intersections based on data provided by fixed observers

    Science.gov (United States)

    Neagu, E.; Boroiu, A. A.; Rizea, V.; Boroiu, A.

    2016-08-01

    For the purposes of the analysis of road traffic at the level of the area surrounding a roundabout intersection there are times when the flows of Origin-Destination (O-D flows) of the respective intersection are of interest - when it is not possible to improve the level of service of the intersection by means of increasing its capacity, but only by diverting some traffic flows from the respective area. Currently, the determining of these O-D flows is based on video recordings of the intersection traffic, followed by laborious and lengthy analyses of the images obtained. But a prolific way, yet not explored in specialised literature, can be the identification of the analytic relations between O-D flow volumes and the volumes of the intersection traffic flows that can be measured by fixed observers (incoming flows, outgoing flows and conflict flows). As a result, this paper presents the research conducted to identify the possible relationships between these deterministic O-D flows and the flows that can be measured by fixed observers. It was demonstrated that, when performing measuring of the flow of vehicles that turn right with fixed observers, there will be analytical deterministic relationships for the 3-armed intersection with return flows, as well as for the 4-armed intersection without return flows. This means that, for 3-armed intersections with return flows and for 4-armed intersections without return flows, it is possible to fully know the O-D flows based on the flows measured by fixed observers (compulsorily involving right-turn flows), which is an absolutely exciting and unique achievement, as knowing these Origin-Destination flows will allow better regulation of the traffic in the area where the roundabout intersection is, in order to facilitate the upstream diversion of some of O-D flows passing through the roundabout intersection.

  3. Comparative study of the Martian suprathermal electron depletions based on Mars Global Surveyor, Mars Express, and Mars Atmosphere and Volatile EvolutioN mission observations

    Science.gov (United States)

    Steckiewicz, M.; Garnier, P.; André, N.; Mitchell, D. L.; Andersson, L.; Penou, E.; Beth, A.; Fedorov, A.; Sauvaud, J.-A.; Mazelle, C.; Brain, D. A.; Espley, J. R.; McFadden, J.; Halekas, J. S.; Larson, D. E.; Lillis, R. J.; Luhmann, J. G.; Soobiah, Y.; Jakosky, B. M.

    2017-01-01

    Nightside suprathermal electron depletions have been observed at Mars by three spacecraft to date: Mars Global Surveyor, Mars Express, and the Mars Atmosphere and Volatile EvolutioN (MAVEN) mission. This spatial and temporal diversity of measurements allows us to propose here a comprehensive view of the Martian electron depletions through the first multispacecraft study of the phenomenon. We have analyzed data recorded by the three spacecraft from 1999 to 2015 in order to better understand the distribution of the electron depletions and their creation mechanisms. Three simple criteria adapted to each mission have been implemented to identify more than 134,500 electron depletions observed between 125 and 900 km altitude. The geographical distribution maps of the electron depletions detected by the three spacecraft confirm the strong link existing between electron depletions and crustal magnetic field at altitudes greater than 170 km. At these altitudes, the distribution of electron depletions is strongly different in the two hemispheres, with a far greater chance to observe an electron depletion in the Southern Hemisphere, where the strongest crustal magnetic sources are located. However, the unique MAVEN observations reveal that below a transition region near 160-170 km altitude the distribution of electron depletions is the same in both hemispheres, with no particular dependence on crustal magnetic fields. This result supports the suggestion made by previous studies that these low-altitudes events are produced through electron absorption by atmospheric CO2.

  4. Statistical challenges in observational cohort studies

    NARCIS (Netherlands)

    Hof, M.H.P.

    2015-01-01

    For over a century observational cohort studies have been used to study determinants of health and disease. Within a sample from the population, we can determine the relation between health outcomes (e.g. death) and a broad range of factors as genetic markers, environmental exposures, and lifestyle

  5. An evaluation of seasonal variations in footwear worn by adults with inflammatory arthritis: a cross-sectional observational study using a web-based survey

    OpenAIRE

    Brenton-Rule, Angela; Hendry, Gordon J; Barr, Georgina; Rome, Keith

    2014-01-01

    Background Foot problems are common in adults with inflammatory arthritis and therapeutic footwear can be effective in managing arthritic foot problems. Accessing appropriate footwear has been identified as a major barrier, resulting in poor adherence to treatment plans involving footwear. Indeed, previous New Zealand based studies found that many people with rheumatoid arthritis and gout wore inappropriate footwear. However, these studies were conducted in a single teaching hospital during t...

  6. Impact of specialist home-based palliative care services in a tertiary oncology set up: A prospective non-randomized observational study

    Directory of Open Access Journals (Sweden)

    Sunil R Dhiliwal

    2015-01-01

    Full Text Available Background: Home-based specialist palliative care services are developed to meet the needs of the patients in advanced stage of cancer at home with physical symptoms and distress. Specialist home care services are intended to improve symptom control and quality of life, enable patients to stay at home, and avoid unnecessary hospital admission. Materials and Methods: Total 690 new cases registered under home-based palliative care service in the year 2012 were prospectively studied to assess the impact of specialist home-based services using Edmonton symptom assessment scale (ESAS and other parameters. Results: Out of the 690 registered cases, 506 patients received home-based palliative care. 50.98% patients were cared for at home, 28.85% patients needed hospice referral and 20.15% patients needed brief period of hospitalization. All patients receiving specialist home care had good relief of physical symptoms ( P < 0.005. 83.2% patients received out of hours care (OOH through liaising with local general practitioners; 42.68% received home based bereavement care and 91.66% had good bereavement outcomes. Conclusion: Specialist home-based palliative care improved symptom control, health-related communication and psychosocial support. It promoted increased number of home-based death, appropriate and early hospice referral, and averted needless hospitalization. It improved bereavement outcomes, and caregiver satisfaction.

  7. Century Scale Evaporation Trend: An Observational Study

    Science.gov (United States)

    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.

  8. Variation of adverse drug reaction profile of platinum-based chemotherapy with body mass index in patients with solid tumors: An observational study

    Directory of Open Access Journals (Sweden)

    Dattatreyo Chatterjee

    2014-01-01

    Full Text Available Objectives: Toxicity of cancer chemotherapy may be affected by nutritional status of patients which is reflected in the body mass index (BMI. We sought to assess whether the adverse drug reaction (ADR profile of platinum-based chemotherapy varies with BMI status. Materials and Methods: Adult patients of either sex, suffering from a solid tumor (lung, head and neck, ovary, gall bladder, stomach, colon and started on platinum-based chemotherapy as initial treatment were included. BMI at chemotherapy commencement was obtained from medical records. Events were recorded and graded as per Eastern Co-operative Oncology Group Common Toxicity Criteria-patients′ complaints; clinically evident signs and laboratory reports were considered. Frequencies of individual adverse events were compared between low BMI (<18.5 kg/m 2 and satisfactory BMI groups. Similar comparisons were done for events with grades 2 or 3 severities. Results: A total of 50 patients were observed over a 3-month period of whom 17 (34% belonged to the low BMI group. Nausea, vomiting, diarrhea, stomatitis, anemia, alopecia, tinnitus and paresthesia were the commonly observed ADRs. The frequencies of anemia (P = 0.152 and vomiting (P = 0.140 and severity of grades of nausea (P = 0.066, anemia (P = 0.120 and paresthesia (P = 0.128 showed a higher trend in the low BMI group though differences were not statistically significant. The frequencies of tinnitus (P = 0.021 and paresthesia overall (P = 0.036 were significantly higher in the low BMI group. Conclusion: ADR profile of primary platinum-based chemotherapy appears to be partly influenced by BMI. This suggests the importance of maintaining adequate nutrition in patients and the need for greater vigilance in those with low BMI.

  9. Astrometric studies of the results of a new reduction of old photographic observations of the Saturnian System based on the comparison with the modern theories of satellite motion

    Science.gov (United States)

    Kiseleva, T. P.; Vasil'eva, T. A.; Roshchina, E. A.; Izmailov, I. S.

    2016-11-01

    The paper shows the possibility of increasing the accuracy of the results of photographic observations of Saturn and its moons made in the 1970s and reduced using the old reference star catalogues and semiautomatic measurements. New celestial coordinates of the moons (from the third to the eighth), "satellite minus satellite" relative moon coordinates, and Saturn coordinates by positions of satellites are obtained without measuring its images. The results are stored in the Pulkovo Observatory database on the Solar System bodies and are available online at www.puldb.ru. The efficiency of the reduction method based on digitizing of astronegatives using 21 Mpx Canon digital camera and IZMCCD software is shown. The comparison of new results of old observations with the latest theories of moon motion has revealed a significant increase in satellite positioning accuracy. The investigation of the differences (O-C) of celestial coordinates from satellite positions in their apparent Saturn-centric orbits has revealed a noticeable motion of the differences (O-C) in right ascension depending on their distances from Saturn for all moons.

  10. Effects of Aerosol on Cloud Liquid Water Path: Statistical Method a Potential Source for Divergence in Past Observation Based Correlative Studies

    Directory of Open Access Journals (Sweden)

    Ousmane Sy Savane

    2015-03-01

    Full Text Available Studies show a divergence in correlation between aerosol and cloud proxies, which has been thought of in the past as the results of varying physical mechanisms. Though modeling studies have supported this idea, from an observational standpoint it is difficult to attribute with confidence the correlations to specific physical mechanisms. We explore a methodology to assess the correlation between cloud water path and aerosol optical depth using Moderate-resolution Imaging Spectroradiometer (MODIS Aqua retrieved aerosol and cloud properties for absorbing and non-absorbing aerosol types over land and over the Atlantic Ocean for various meteorological conditions. The data covers a three-month period, June through August, during which different aerosol types are predominant in specific regions. Our approach eliminates outliers; sorts the data into aerosol bins; and the mean Aerosol Optical Depth (AOD value for each bin and the corresponding mean Cloud Water Path (CWP value are determined. The mean CWP is plotted against the mean AOD. The response curve for all aerosol types shows a peak CWP value corresponding to an aerosol loading value AODpeak. The peak is used to divide the total range of aerosol loading into two sub ranges. For AOD value below AODpeak, mean CWP and mean AOD are positively correlated. The correlation between mean CWP and mean AOD is negative for aerosol loading above AODpeak. Irrespective of aerosol type, atmospheric water vapor content and lower tropospheric static stability, the peak observed for each aerosol type seems to describe a universal feature that calls for further investigation. It has been observed for a variety of geographical locations and different seasons.

  11. Observer and observer-based H∞ control of generalized Hamiltonian systems

    Institute of Scientific and Technical Information of China (English)

    WANG Yuzhen; GE S. S.; CHENG Daizhan

    2005-01-01

    This paper deals with observer design for generalized Hamiltonian systems and its applications. First, by using the systems' structural properties, a new observer design method called Augment Plus Feedback is provided and two kinds of observers are obtained: non-adaptive and adaptive ones. Then, based on the obtained observer, H∞ control design is investigated for generalized Hamiltonian systems, and an observer-based control design is proposed. Finally, as an application to power systems, an observer and an observer-based H∞ control law are designed for single-machine infinite-bus systems.Simulations show that both the observer and controller obtained in this paper work very well.

  12. Accelerometer-based physical activity in a large observational cohort - study protocol and design of the activity and function of the elderly in Ulm (ActiFE Ulm study

    Directory of Open Access Journals (Sweden)

    Duran-Tauleria Enric

    2010-07-01

    Full Text Available Abstract Background A large number of studies have demonstrated a positive effect of increased physical activity (PA on various health outcomes. In all large geriatric studies, however, PA has only been assessed by interview-based instruments which are all subject to substantial bias. This may represent one reason why associations of PA with geriatric syndromes such as falls show controversial results. The general aim of the Active-Ulm study was to determine the association of accelerometer-based physical activity with different health-related parameters, and to study the influence of this standardized objective measure of physical activity on health- and disability-related parameters in a longitudinal setting. Methods We have set up an observational cohort study in 1500 community dwelling older persons (65 to 90 years stratified by age and sex. Addresses have been obtained from the local residents registration offices. The study is carried out jointly with the IMCA - Respiratory Health Survey in the Elderly implemented in the context of the European project IMCA II. The study has a cross-sectional part (1 which focuses on PA and disability and two longitudinal parts (2 and (3. The primary information for part (2 is a prospective 1 year falls calendar including assessment of medication change. Part (3 will be performed about 36 months following baseline. Primary variables of interest include disability, PA, falls and cognitive function. Baseline recruitment has started in March 2009 and will be finished in April 2010. All participants are visited three times within one week, either at home or in the study center. Assessments included interviews on quality of life, diagnosed diseases, common risk factors as well as novel cognitive tests and established tests of physical functioning. PA is measured using an accelerometer-based sensor device, carried continuously over a one week period and accompanied by a prospective activity diary. Discussion The

  13. Observer-based monitoring of heat exchangers.

    Science.gov (United States)

    Astorga-Zaragoza, Carlos-Manuel; Alvarado-Martínez, Víctor-Manuel; Zavala-Río, Arturo; Méndez-Ocaña, Rafael-Maxim; Guerrero-Ramírez, Gerardo-Vicente

    2008-01-01

    The goal of this work is to provide a method for monitoring performance degradation in counter-flow double-pipe heat exchangers. The overall heat transfer coefficient is estimated by an adaptive observer and monitored in order to infer when the heat exchanger needs preventive or corrective maintenance. A simplified mathematical model is used to synthesize the adaptive observer and a more complex model is used for simulation. The reliability of the proposed method was demonstrated via numerical simulations and laboratory experiments with a bench-scale pilot plant.

  14. Different responses of northern and southern high latitude ionospheric convection to IMF rotations: a case study based on SuperDARN observations

    Directory of Open Access Journals (Sweden)

    D. Ambrosino

    2009-06-01

    Full Text Available We use SuperDARN data to study high-latitude ionospheric convection over a three hour period (starting at 22:00 UT on 2 January 2003, during which the Interplanetary Magnetic Field (IMF flipped between two states, one with By>>|Bz| and one with Bz>0, both with negative Bx. We find, as expected from previous works, that day side ionospheric convection is controlled by the IMF in both hemispheres. For strongly northward IMF, we observed signatures of two reverse cells, both in the Northern Hemisphere (NH and in the Southern Hemisphere (SH, due to lobe reconnection. On one occasion, we also observed in the NH two viscous cells at the sides of the reverse cell pair. For duskward IMF, we observed in the NH a large dusk clockwise cell, accompanied by a smaller dawn cell, and the signature of a corresponding pattern in the SH. On two occasions, a three cell pattern, composed of a large clockwise cell and two viscous cells, was observed in the NH. As regards the timings of the NH and SH convection reconfigurations, we find that the convection reconfiguration from a positive Bz dominated to a positive By dominated pattern occurred almost simultaneously (i.e. within a few minutes in the two hemispheres. On the contrary, the reconfiguration from a By dominated to a northward IMF pattern started in the NH 8–13 min earlier than in the SH. We suggest that part of such a delay can be due to the following mechanism: as IMF Bx<0, the northward-tailward magnetosheath magnetic field reconnects with the magnetospheric field first tailward of the northern cusp and later on tailward of the southern cusp, due to the IMF draping around the magnetopause.

  15. Ozone Lidar Observations for Air Quality Studies

    Science.gov (United States)

    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.

  16. Chaos synchronization based on intermittent state observer

    Institute of Scientific and Technical Information of China (English)

    Li Guo-Hui; Zhou Shi-Ping; Xu De-Ming

    2004-01-01

    This paper describes the method of synchronizing slave to the master trajectory using an intermittent state observer by constructing a synchronizer which drives the response system globally tracing the driving system asymptotically. It has been shown from the theory of synchronization error-analysis that a satisfactory result of chaos synchronization is expected under an appropriate intermittent period and state observer. Compared with continuous control method,the proposed intermittent method can target the desired orbit more efficiently. The application of the method is demonstrated on the hyperchaotic Rossler systems. Numerical simulations show that the length of the synchronization interval rs is of crucial importance for our scheme, and the method is robust with respect to parameter mismatch.

  17. The NOAA Satellite Observing System Architecture Study

    Science.gov (United States)

    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.

  18. Data base to compare calculations and observations

    Energy Technology Data Exchange (ETDEWEB)

    Tichler, J.L.

    1985-01-01

    Meteorological and climatological data bases were compared with known tritium release points and diffusion calculations to determine if calculated concentrations could replace measure concentrations at the monitoring stations. Daily tritium concentrations were monitored at 8 stations and 16 possible receptors. Automated data retrieval strategies are listed. (PSB)

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

    Science.gov (United States)

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

    2015-03-01

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

  20. A study of the long-term properties of Jovian hot spots from HST and ground-based observations between 1994 and 1998

    Science.gov (United States)

    Arregui, E.; Rojas, J. F.; Sanchez-Lavega, A.; Lecacheux, J.; Colas, F.; Miyazaki, I.; Parker, D.

    2000-10-01

    We have used the HST-WFPC2 archived images of Jupiter in the period 1994-1998 together with a large set of CCD ground based images, to study the zonal distribution, long-term motions, lifetimes, interactions and other properties of the hot spot - plume regions at 7 degrees North. Red and near infrared filters covering the wavelength range 650 - 953 nm have been used since they show the hot spots with a high contrast. We have found that the hot spots have velocities ranging from 95 to 112 m/s and are grouped typically in families of three to six members. We do not found any correlation between their velocity and wavenumber. The long-term survey allowed us to identify mergers and splitting of the hot spots areas. The Spanish team was supported by Gobierno Vasco PI 034/97. The French team was supported by the "Programme National de Planetologie."

  1. Forbush Decrease Prediction Based on the Remote Solar Observations

    CERN Document Server

    Dumbovic, Mateja; Calogovic, Jasa

    2015-01-01

    We employ remote observations of coronal mass ejections (CMEs) and the associated solar flares to forecast the CME-related Forbush decreases, i.e., short-term depressions in the galactic cosmic-ray flux. The relationship between the Forbush effect at the Earth and remote observations of CMEs and associated solar flares is studied via a statistical analysis. Relationships between Forbush decrease magnitude and several CME/flare parameters was found, namely the initial CME speed, apparent width, source position, associated solar-flare class and the effect of successive-CME occurrence. Based on the statistical analysis, remote solar observations are employed for a Forbush-decrease forecast. For that purpose, an empirical probabilistic model is constructed that uses selected remote solar observations of CME and associated solar flare as an input, and gives expected Forbush-decrease magnitude range as an output. The forecast method is evaluated using several verification measures, indicating that as the forecast t...

  2. Shooting history and presence of high-frequency hearing impairment in swedish hunters: A cross-sectional internet-based observational study.

    Science.gov (United States)

    Honeth, Louise; Ström, Peter; Ploner, Alexander; Bagger-Sjöbäck, Dan; Rosenhall, Ulf; Nyrén, Olof

    2015-01-01

    The aim of this cross-sectional study among Swedish hunters was to examine the association between shooting history and presence of high-frequency hearing impairment (HFHI). All hunters registered with an e-mail address in the membership roster of the Swedish Hunters' Association were invited via e-mail to a secure website with a questionnaire and an Internet-based audiometry test. Associations, expressed as prevalence ratio (PR), were multivariately modelled using Poisson regression. The questionnaire was answered by 1771 hunters (age 11-91 years), and 202 of them also completed the audiometry test. Subjective severe hearing loss was reported by 195/1771 (11%), while 23/202 (11%) exhibited HFHI upon testing with Internet-based audiometry. As many as 328/1771 (19%) had never used hearing protection during hunting. In the preceding 5 years, 785/1771 (45%), had fired >6 unprotected gunshots with hunting rifle calibers. The adjusted PR of HFHI when reporting 1-6 such shots, relative to 0, was 1.5 [95% confidence interval (CI) 1.1-2.1; P = 0.02]. We could not verify any excessive HFHI prevalence among 89 hunters reporting unprotected exposure to such gunshot noise >6 times. Nor did the total number of reported rifle shots seem to matter. These findings support the notion of a wide variation in individual susceptibility to impulse noise; that significant sound energy, corresponding to unprotected noise from hunting rifle calibers, seems to be required; that susceptible individuals may sustain irreversible damage to the inner ear from just one or a few shots; and that use of hearing protection should be encouraged from the first shot with such weapons.

  3. Shooting history and presence of high-frequency hearing impairment in swedish hunters: A cross-sectional internet-based observational study

    Directory of Open Access Journals (Sweden)

    Louise Honeth

    2015-01-01

    Full Text Available The aim of this cross-sectional study among Swedish hunters was to examine the association between shooting history and presence of high-frequency hearing impairment (HFHI. All hunters registered with an e-mail address in the membership roster of the Swedish Hunters′ Association were invited via e-mail to a secure website with a questionnaire and an Internet-based audiometry test. Associations, expressed as prevalence ratio (PR, were multivariately modelled using Poisson regression. The questionnaire was answered by 1771 hunters (age 11-91 years, and 202 of them also completed the audiometry test. Subjective severe hearing loss was reported by 195/1771 (11%, while 23/202 (11% exhibited HFHI upon testing with Internet-based audiometry. As many as 328/1771 (19% had never used hearing protection during hunting. In the preceding 5 years, 785/1771 (45%, had fired >6 unprotected gunshots with hunting rifle calibers. The adjusted PR of HFHI when reporting 1-6 such shots, relative to 0, was 1.5 [95% confidence interval (CI 1.1-2.1; P = 0.02]. We could not verify any excessive HFHI prevalence among 89 hunters reporting unprotected exposure to such gunshot noise >6 times. Nor did the total number of reported rifle shots seem to matter. These findings support the notion of a wide variation in individual susceptibility to impulse noise; that significant sound energy, corresponding to unprotected noise from hunting rifle calibers, seems to be required; that susceptible individuals may sustain irreversible damage to the inner ear from just one or a few shots; and that use of hearing protection should be encouraged from the first shot with such weapons.

  4. Hospitalisation with community-acquired pneumonia among patients with type 2 diabetes: an observational population-based study in Spain from 2004 to 2013

    Science.gov (United States)

    López-de-Andrés, Ana; de Miguel-Díez, Javier; Jiménez-Trujillo, Isabel; Hernández-Barrera, Valentín; de Miguel-Yanes, José M; Méndez-Bailón, Manuel; Pérez-Farinós, Napoleón; Salinero-Fort, Miguel Á ngel; Jiménez-García, Rodrigo

    2017-01-01

    Objectives To describe trends in the incidence and outcomes of community-acquired pneumonia (CAP) hospitalisations among patients with or without diabetes in Spain (2004–2013). Design Retrospective, observational study using the Spanish National Hospital Discharge Database (Conjunto Mínimo Básico de Datos (CMBD)). Setting Spain. Participants We used national hospital discharge data to select all hospital admissions for CAP. Main outcome measures Incidence was calculated overall and stratified by diabetes status: type 2 diabetes mellitus (T2DM) and no diabetes. Results We identified 901 136 admissions for CAP (24.8% with T2DM). Incidence rates of CAP increased significantly in patients with T2DM over time. The incidence was higher among people with T2DM for all time periods. Patients with T2DM were older and had higher comorbidity index than non-diabetics. Streptococcus pneumoniae decreased over time for both groups. Time trend analyses showed significant decreases in mortality during admission for CAP for patients with and without T2DM. Factors associated with higher mortality in both groups included: older age, higher comorbidity, mechanical ventilation, red cell transfusion, readmission and Staphylococcus aureus detection. Diabetes was associated with a lower in-hospital mortality (OR 0.92, 95% CI 0.91 to 0.94) after a CAP hospitalisation. Conclusions CAP incidence rates were higher and increased over time at a higher rate among patients with T2DM. Mortality decreased over time in all groups. The presence of diabetes is not a risk factor for death during admission for CAP. PMID:28057653

  5. Assessing the Viability of Social Media for Disseminating Evidence-Based Nutrition Practice Guideline Through Content Analysis of Twitter Messages and Health Professional Interviews: An Observational Study

    Science.gov (United States)

    Kenne, Deric; Wolfram, Taylor M; Abram, Jenica K; Fleming, Michael

    2016-01-01

    Background Given the high penetration of social media use, social media has been proposed as a method for the dissemination of information to health professionals and patients. This study explored the potential for social media dissemination of the Academy of Nutrition and Dietetics Evidence-Based Nutrition Practice Guideline (EBNPG) for Heart Failure (HF). Objectives The objectives were to (1) describe the existing social media content on HF, including message content, source, and target audience, and (2) describe the attitude of physicians and registered dietitian nutritionists (RDNs) who care for outpatient HF patients toward the use of social media as a method to obtain information for themselves and to share this information with patients. Methods The methods were divided into 2 parts. Part 1 involved conducting a content analysis of tweets related to HF, which were downloaded from Twitonomy and assigned codes for message content (19 codes), source (9 codes), and target audience (9 codes); code frequency was described. A comparison in the popularity of tweets (those marked as favorites or retweeted) based on applied codes was made using t tests. Part 2 involved conducting phone interviews with RDNs and physicians to describe health professionals’ attitude toward the use of social media to communicate general health information and information specifically related to the HF EBNPG. Interviews were transcribed and coded; exemplar quotes representing frequent themes are presented. Results The sample included 294 original tweets with the hashtag “#heartfailure.” The most frequent message content codes were “HF awareness” (166/294, 56.5%) and “patient support” (97/294, 33.0%). The most frequent source codes were “professional, government, patient advocacy organization, or charity” (112/277, 40.4%) and “patient or family” (105/277, 37.9%). The most frequent target audience codes were “unable to identify” (111/277, 40.1%) and “other” (55

  6. Space-based observation of the extensive airshowers

    Directory of Open Access Journals (Sweden)

    Ebisuzaki T.

    2013-06-01

    Full Text Available Space based observations of extensive air showers constitute the next experimental challenge for the study of the universe at extreme energy. Space observation will allow a “quantum jump” in the observational area available to detect the UV light tracks produced by particles with energies higher than 1020 eV. These are thought to reach the Earth almost undeflected by the cosmic magnetic field. This new technique will contribute to establish the new field of astronomy and astrophysics performed with charged particles and neutrinos at the highest energies. This idea was created by the incredible efforts of three outstanding comic ray physicists: John Linsley, Livio Scarsi, and Yoshiyuki Takahashi. This challenging technique has four significant merits in comparison with ground-based observations: 1 Very large observational area, 2 Well constrained distances of the showers, 3 Clear and stable atmospheric transmission in the above half troposphere, 4 Uniform Exposure across both the north and south skies. Four proposed and planned missions constitute the roadmap of the community: TUS, JEM-EUSO, KLPVE, and Super-EUSO will contribute step-by-step to establish this challenging field of research.

  7. Universal HbA1c Measurement in Early Pregnancy to Detect Type 2 Diabetes Reduces Ethnic Disparities in Antenatal Diabetes Screening: A Population-Based Observational Study.

    Directory of Open Access Journals (Sweden)

    R C E Hughes

    Full Text Available In response to the type 2 diabetes epidemic, measuring HbA1c with the first-antenatal blood screen was recently recommended in NZ. This would enable prompt treatment of women with unrecognised type 2 diabetes, who may otherwise go undetected until the gestational diabetes (GDM screen. We compare inter-ethnic antenatal screening practices to examine whether the HbA1c test would be accessed by ethnicities most at risk of diabetes, and we determined the prevalence of unrecognised type 2 diabetes and prediabetes in our pregnant population. This is an observational study of pregnancies in Christchurch NZ during 2008-2010. Utilising electronic databases, we matched maternal characteristics to first-antenatal bloods, HbA1c, and GDM screens (glucose challenge tests and oral glucose tolerance tests. Overall uptake of the first-antenatal bloods versus GDM screening was 83.1% and 53.8% respectively in 11,580 pregnancies. GDM screening was lowest in Māori 39.3%, incidence proportion ratio (IPR 0.77 (0.71, 0.84 compared with Europeans. By including HbA1c with the first-antenatal bloods, the number screened for diabetes increases by 28.5% in Europeans, 40.0% in Māori, 28.1% in Pacific People, and 26.7% in 'Others' (majority of Asian descent. The combined prevalence of unrecognised type 2 diabetes and prediabetes by NZ criteria, HbA1c ≥5.9% (41mmol/mol, was 2.1% in Europeans, Māori 4.7% IPR 2.59 (1.71, 3.93, Pacific People 9.5% IPR 4.76 (3.10, 7.30, and 'Others' 6.2% IPR 2.99 (2.19, 4.07. Applying these prevalence data to 2013 NZ national births data, routine antenatal HbA1c testing could have identified type 2 diabetes in 0.44% and prediabetes in 3.96% of women. Routine HbA1c measurement in early pregnancy is an ideal screening opportunity, particularly benefitting vulnerable groups, reducing ethnic disparities in antenatal diabetes screening. This approach is likely to have world-wide relevance and applicability. Further research is underway to

  8. The study of seasonal composition and dynamics of wetland ecosystems and wintering bird habitat at Poyang Lake, PR China using object-based image analysis and field observations

    Science.gov (United States)

    Dronova, Iryna

    Wetlands are among the most productive ecosystems in the world which support critical ecological services and high biological diversity yet are vulnerable to climate change and human activities. In this thesis, I investigated the capabilities of satellite remote sensing with medium spatial resolution and object-based image analysis (OBIA) methods to elucidate seasonal composition and dynamics of wetland ecosystems and indicators of habitat for wintering waterbirds in a large conservation hotspot of Poyang Lake, PR China. I first examined changes in major wetland cover types during the low water period when Poyang Lake provides habitat to large numbers of migratory birds from the East Asian pathway. I used OBIA to map and analyze the transitions among water, vegetation, mudflat and sand classes from four 32-m Beijing-1 microsatellite images between late fall 2007 and early spring 2008. This analysis revealed that, while transitions among wetland classes were strongly associated with precipitation and flood-driven hydrological variation, the overall dynamics were a more complex interplay of vegetation phenology, disturbance and post-flood exposure. Remote sensing signals of environmental processes were more effectively captured by changes in fuzzy memberships to each class per location than by changes in spatial extents of the best-matching classes alone. The highest uncertainty in the image analysis corresponded to transitional wetland states at the end of the major flood recession in November and to heterogeneous mudflat areas at the land-water interface during the whole study period. Results suggest seasonally exposed mudflat features as important targets for future research due to heterogeneity and uncertainty of their composition, variable spatial distribution and sensitivity to hydrological dynamics. I further explored the potential of OBIA to overcome the limitations of the traditional pixel-based image classification methods in characterizing Poyang Lake

  9. Impact of home environment interventions on the risk of influenza-associated ARI in Andean children: observations from a prospective household-based cohort study.

    Directory of Open Access Journals (Sweden)

    Philip J Budge

    Full Text Available BACKGROUND: The Respiratory Infections in Andean Peruvian Children (RESPIRA-PERU study enrolled children who participated in a community-cluster randomized trial of improved stoves, solar water disinfection, and kitchen sinks (IHIP trial and children from additional Andean households. We quantified the burden of influenza-associated acute respiratory illness (ARI in this household-based cohort. METHODS: From May 2009 to September 2011, we conducted active weekly ARI surveillance in 892 children age <3 years, of whom 272 (30.5% had participated in the IHIP trial. We collected nasal swabs during ARI, tested for influenza and other respiratory viruses by RT-PCR, and determined influenza incidence and risk factors using mixed-effects regression models. RESULTS: The overall incidence of influenza-associated ARI was 36.6/100 child-years; incidence of influenza A, B, and C was 20.5, 8.7, and 5.2/100 child-years, respectively. Influenza C was associated with fewer days of subjective fever (median 1 vs. 2 and malaise (median 0 vs. 2 compared to influenza A. Non-influenza ARI also resulted in fewer days of fever and malaise, and fewer healthcare visits than influenza A-associated ARI. Influenza incidence varied by calendar year (80% occurred in the 2010 season and IHIP trial participation. Among households that participated in the IHIP trial, influenza-associated ARI incidence was significantly lower in intervention than in control households (RR 0.40, 95% CI: 0.20-0.82. CONCLUSIONS: Influenza burden is high among Andean children. ARI associated with influenza A and B had longer symptom duration and higher healthcare utilization than influenza C-associated ARI or non-influenza ARI. Environmental community interventions may reduce influenza morbidity.

  10. Observer-based Satellite Attitude Control and Simulation Researches

    Institute of Scientific and Technical Information of China (English)

    王子才; 马克茂

    2002-01-01

    Observer design method is applied to the realization of satellite attitude control law baaed on simplified control model. Exact mathematical model of the satellite attitude control system is also constructed, together with the observer-based control law, to conduct simulation research. The simulation results justify the effectiveness andfeasibility of the observer-based control method.

  11. A LONGITUDINAL-STUDY OF INTERACTION PATTERNS OF A PSYCHIATRIST AND SEVERELY DEPRESSED-PATIENTS BASED ON OBSERVED BEHAVIOR - AN ETHOLOGICAL APPROACH OF INTERPERSONAL THEORIES OF DEPRESSION

    NARCIS (Netherlands)

    BOUHUYS, AL; VANDENHOOFDAKKER, RH

    1993-01-01

    Observed behaviour of a psychiatrist interacting with severely depressed patients during an interview was related to the course of depression during hospitalization. The behavioural structure of such interaction could be described by 6 factors for the patients and 7 factors for the psychiatrist. The

  12. Observer rated sleepiness and real road driving: an explorative study.

    Directory of Open Access Journals (Sweden)

    Anna Anund

    Full Text Available 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.

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

    Directory of Open Access Journals (Sweden)

    Erik von Elm

    2007-10-01

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

  14. Estimating Evapotranspiration Using an Observation Based Terrestrial Water Budget

    Science.gov (United States)

    Rodell, Matthew; McWilliams, Eric B.; Famiglietti, James S.; Beaudoing, Hiroko K.; Nigro, Joseph

    2011-01-01

    Evapotranspiration (ET) is difficult to measure at the scales of climate models and climate variability. While satellite retrieval algorithms do exist, their accuracy is limited by the sparseness of in situ observations available for calibration and validation, which themselves may be unrepresentative of 500m and larger scale satellite footprints and grid pixels. Here, we use a combination of satellite and ground-based observations to close the water budgets of seven continental scale river basins (Mackenzie, Fraser, Nelson, Mississippi, Tocantins, Danube, and Ubangi), estimating mean ET as a residual. For any river basin, ET must equal total precipitation minus net runoff minus the change in total terrestrial water storage (TWS), in order for mass to be conserved. We make use of precipitation from two global observation-based products, archived runoff data, and TWS changes from the Gravity Recovery and Climate Experiment satellite mission. We demonstrate that while uncertainty in the water budget-based estimates of monthly ET is often too large for those estimates to be useful, the uncertainty in the mean annual cycle is small enough that it is practical for evaluating other ET products. Here, we evaluate five land surface model simulations, two operational atmospheric analyses, and a recent global reanalysis product based on our results. An important outcome is that the water budget-based ET time series in two tropical river basins, one in Brazil and the other in central Africa, exhibit a weak annual cycle, which may help to resolve debate about the strength of the annual cycle of ET in such regions and how ET is constrained throughout the year. The methods described will be useful for water and energy budget studies, weather and climate model assessments, and satellite-based ET retrieval optimization.

  15. Identification of precipitation onset based on Cloudsat observations

    Science.gov (United States)

    Wang, Yu; Chen, Yujue; Fu, Yunfei; Liu, Guosheng

    2017-02-01

    Observations of cloud vertical structure by Cloud Profiling Radar on CloudSat satellite provide a unique opportunity to globally identify the onset of precipitation. In this study, based on a conceptual model for an adiabatic cloud, a new method to determine the onset of precipitation in marine warm clouds is developed. The new method uses the slope of radar reflectivities near the cloud top, which gradually reverses its signs as drizzle occurs. By analyzing multiyear CloudSat data, it is found that globally the radar reflectivity threshold for precipitation onset varies from -18 to -13 dBZ with an average value of -16 dBZ. The corresponding liquid water path threshold for precipitation onset is also studied by analyzing satellite microwave observations collocated with CloudSat data. Results show that the liquid water path threshold is 190 g m-2 as a global mean, varying from 150 to over 300 g m-2 depending on regions.

  16. Cassini observations of carbon-based anions in Titan's ionosphere

    Science.gov (United States)

    Desai, Ravindra; Lewis, Gethyn; Waite, J. Hunter; Kataria, Dhiren; Wellbrock, Anne; Jones, Geraint; Coates, Andrew

    2016-07-01

    Cassini observations of Titan's ionosphere revealed an atmosphere rich in positively and negatively charged ions and organic molecules. The detection of large quantities of negatively charged ions was particularly surprising and adds Titan to the growing list of locations where anion chemistry has been observed to play an important role. In this study we present updated analysis on these negatively charged ions through an enhanced understanding of the Cassini CAPS Electron Spectrometer (CAPS-ELS) instrument response. The ionisation of Titan's dominant atmospheric constituent, N2, by the HeII Solar line, results in an observable photoelectron population at 24.1eV which we use to correct for differential spacecraft charging. Correcting for further energy-angle signatures within this dataset, we use an updated fitting procedure to show how the ELS mass spectrum, previously grouped into broad mass ranges, can be resolved into specific peaks at multiples of carbon-based anion species up to over 100amu/q. These peaks are shown to be ubiquitous within Titan's upper atmosphere and reminiscent of carbon-based anions identified in dense molecular clouds beyond our Solar System. It is thus shown how the moon Titan in the Outer Solar System can be used as an analogue to study these even more remote and exotic astrophysical environments.

  17. Observation of supercurrent in graphene-based Josephson junction

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Libin; Li, Sen; Kang, Ning [Key Laboratory for the Physics and Chemistry of Nanodevices and Department of Electronics, Peking University, Beijing 100871 (China); Xu, Chuan; Ren, Wencai [Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China)

    2015-07-01

    Josephson junctions with a normal metal region sandwiched between two superconductors (S) are known as superconductor- normal-superconductor (SNS) structures. It has attracted significant attention especially when changing the normal metal with graphene, which allow for high tunability with the gate voltage and to study the proximity effect of the massless Dirac fermions. Here we report our work on graphene-based Josephson junction with a new two dimensional superconductor crystal, which grown directly on graphene, as superconducting electrodes. At low temperature, we observer proximity effect induced supercurrent flowing through the junction. The temperature and the magnetic field dependences of the critical current characteristics of the junction are also studied. The critical current exhibits a Fraunhofer-type diffraction pattern against magnetic field. Our experiments provided a new route of fabrication of graphene-based Josephson junction.

  18. An Observational Study of Entrainment Rate in Deep Convection

    OpenAIRE

    Xiaohao Guo; Chunsong Lu; Tianliang Zhao; Guang J. Zhang; Yangang Liu

    2015-01-01

    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...

  19. Age at Menarche, Level of Education, Parity and the Risk of Hysterectomy: A Systematic Review and Meta-Analyses of Population-Based Observational Studies.

    Directory of Open Access Journals (Sweden)

    Louise F Wilson

    Full Text Available Although rates have declined, hysterectomy is still a frequent gynaecological procedure. To date, there has been no systematic quantification of the relationships between early/mid-life exposures and hysterectomy. We performed a systematic review and meta-analyses to quantify the associations between age at menarche, education level, parity and hysterectomy.Eligible studies were identified by searches in PubMed and Embase through March 2015. Study-specific estimates were summarised using random effects meta-analysis. Heterogeneity was explored using sub-group analysis and meta-regression.Thirty-two study populations were identified for inclusion in at least one meta-analysis. Each year older at menarche was associated with lower risk of hysterectomy-summary hazard ratio 0.86 (95% confidence interval: 0.78, 0.95; I2 = 0%; summary odds ratio 0.88 (95% confidence interval: 0.82, 0.94; I2 = 61%. Low education levels conferred a higher risk of hysterectomy in the lowest versus highest level meta-analysis (summary hazard ratio 1.87 (95% confidence interval: 1.25, 2.80; I2 = 86%, summary odds ratio 1.51 (95% confidence interval: 1.35, 1.69; I2 = 90% and dose-response meta-analysis (summary odds ratio 1.17 (95% confidence interval: 1.12, 1.23; I2 = 85% per each level lower of education. Sub-group analysis showed that the birth cohort category of study participants, the reference category used for level of education, the year the included article was published, quality of the study (as assessed by the authors and control for the key variables accounted for the high heterogeneity between studies in the education level meta-analyses. In the meta-analyses of studies of parity and hysterectomy the results were not statistically significant.The present meta-analyses suggest that the early life factors of age at menarche and lower education level are associated with hysterectomy, although this evidence should be interpreted with some caution due to variance

  20. Influence of seabed topography on the distribution of manganese nodules and associated features in the Central Indian Basin: A study based on photographic observations

    Digital Repository Service at National Institute of Oceanography (India)

    Sharma, R.; Kodagali, V.N.

    , for their encouragement and guidance. The authors acknowledge the suggestions and comments of the reviewers Drs. G.P. Glasby and M.J. Cruickshank. This study was carried out under the Polymetallic Nodules Programme, financed by the Department of Ocean Develop- ment...

  1. Bumpless Transfer between Observer-based Gain Scheduled Controllers

    DEFF Research Database (Denmark)

    Bendtsen, Jan Dimon; Stoustrup, Jakob; Trangbæk, Klaus

    2005-01-01

    This paper deals with bumpless transfer between a number of observer-based controllers in a gain scheduling architecture. Linear observer-based controllers are designed for a number of linear approximations of a nonlinear system in a set of operating points, and gain scheduling control can...

  2. Factors affecting well-being and socio-occupational functioning in schizophrenia patients following an acute exacerbation: A hospital based observational study

    Directory of Open Access Journals (Sweden)

    Roopa Gopalakrishnan

    2015-01-01

    Full Text Available Background: Improving functioning levels are an important goal of treatment in schizophrenia. Most studies have described long-term course and outcome in schizophrenia. However, understanding factors influencing functioning in the immediate recovery period following an acute exacerbation may be of important clinical relevance. Aim: The aim of this study is to assess the factors that influence well-being and socio-occupational functioning following an acute exacerbation in schizophrenia patients. Materials and Methods: The study included 40 patients during the period from June 2013 to June 2014. The possible effect of gender, duration of illness, duration of untreated psychosis, premorbid adjustment, cognitive impairment, facial affect perception and treatment compliance on well-being, and socio-occupational functioning was examined. Results : About 45% of the individuals experienced below average well-being. On logistic regression analysis poor compliance with medication and poorer cognitive functioning significantly differentiated the patient group with below average well-being from those with an above average well-being. Male gender, poor premorbid adjustment, poor compliance to treatment, poor cognitive functioning, and greater duration of untreated psychosis were found to be associated with a poorer socio-occupational functioning. Conclusion: Clinical interventions focusing on improving cognitive impairment and compliance to treatment could play a role in improving well-being, and socio-occupational functioning in schizophrenia patients following an acute exacerbation.

  3. Simulating Observer in Supervisory Control- A Domain-based Method

    Directory of Open Access Journals (Sweden)

    Seyed Morteza Babamir

    2012-06-01

    Full Text Available An Observer in the supervisory control observes responses of a discrete system to events of its environment and reports an unsafe/ critical situation if the response is undesired. An undesired response from the system indicates the system response does not adhere to users’ requirements of the system. Therefore, events and conditions of the system environment and user’s requirements of the system are basic elements to observer in determining correctness of the system response. However, the noteworthy matter is that the events, conditions, and requirements should be defined based on data of problem domain because discrete data are primary ingredients of the environment in discrete systems and they are used by system users as a gauge to express their requirements playing a vital role in safety-critical systems, such as medical and avionic ones. A large quantity of methods has already been proposed to model and simulate supervisory control of discrete systems however, a systematic method relying on data of problem domain is missing. Having extracted events, conditions, and user’s requirements from data of problem domain, a Petri-Net automaton is constructed for identifying violation of user’s requirements. The net constitutes the core of the observer and it is used to identify undesired responses of the system. In the third step, run-time simulation of the observer is suggested using multithreading mechanism and Task Parallel Library (TPL technology of Microsoft. Finally, a case study of a discrete concurrent system is proposed, the method applied and simulation results are analyzed based on the system implementation on a multi-core computer.

  4. Study on wind resistant design of long-span bridges based on field observation result; Dotai kansoku kekka ni motozuku chodaikyo no taifu sekkei ni kansuru kosatsu

    Energy Technology Data Exchange (ETDEWEB)

    Katsuchi, H.; Tada, K.; Kitagawa, M.

    1996-07-21

    Based on records of strong wind and bridge response to the 19th typhoon in 1991 and 13th typhoon in 1993 at the Onaruto Bridge and the Minami Bisan-Seto Bridge as well as results of numerical analysis, the validity of wind resistant design was investigated. The validity of current wind resistant design was confirmed for the intensity of turbulence and the power spectrum among the natural wind properties. The spatial correlation property was expressed better by Karman`s correlation equation than by usual exponential function equation. The bridge response value was evaluated well by using Karman`s correlation equation, as to bridge response properties, and especially the gust response properties. It was more rational to apply Karman`s correlation equation rather than usual exponential equation to the wind resistant design of long-span bridges. It was suggested that the evaluation of the wind load in the wind resistant design can be reduced. Accordingly, the design of long-span bridges, whose structures can be determined by the wind load, can be rationalized. 20 refs., 13 figs., 2 tabs.

  5. The positive role of breastfeeding on infant health during the first 6 weeks: findings from a prospective observational study based on maternal reports.

    LENUS (Irish Health Repository)

    Tarrant, R C

    2012-03-01

    This study aimed to report on adverse infant and maternal clinical outcomes, and investigate the relationship between infant feeding practice and such adverse clinical outcomes in infants during the first 6 weeks postpartum. From an eligible sample of 450 mother-term infant pairs recruited from the Coombe Women and Infants University Hospital in Dublin, 27.1% of infants (n=122) were maternally reported to have had an illness during the first 6 weeks that necessitated the provision of prescribed medication +\\/- general practitioner\\/paediatrician attendance +\\/- hospitalisation. Of these, 90 infants had > or =1 episode of infection +\\/- viral +\\/- gastro-intestinal-related condition. After adjustment, \\'any\\' breastfeeding to 6 weeks was protective against such adverse infant outcomes (adjusted odds ratio [aOR] 0.44, P = 0.022). Attendance to the GP\\/paediatrician for > 1 visit (aOR 3.44, P = 0.000) and multiparity (aOR 1.76, P = 0.041) were also positively associated with such adverse infant outcomes. To decrease infant morbidity rates in Ireland, government investment in breastfeeding promotion, support and research should be a continued public health priority.

  6. Observational Study of Solar Magnetic Active Phenomena

    Indian Academy of Sciences (India)

    Hongqi Zhang

    2006-06-01

    The electric current separated into two parts reflected the quantative properties of heterogeneity and chirality of magnetic field, and defined them as the shear and twist components of current. We analyze the basic configuration and evolution of superactive region NOAA 6580-6619-6659. It is found that the contribution of the twist component of current cannot be reflected in the normal analysis of the magnetic shear and gradient of the active regions. The observational evidence of kink magnetic ropes generated from the subatmosphere cannot be found completely in some super delta active regions.

  7. Potential New Lidar Observations for Cloud Studies

    Science.gov (United States)

    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.

  8. On estimating the force-freeness based on observed magnetograms

    CERN Document Server

    Zhang, X M; Su, J T

    2016-01-01

    It is a common practice in the solar physics community to test whether or not measured photospheric or chromospheric vector magnetograms are force-free, using the Maxwell stress as a measure. Some previous studies have suggested that magnetic fields of active regions in the solar chromosphere are close to be force-free whereas there is no consistency among previous studies on whether magnetic fields of active regions in the solar photosphere are force-free or not. Here we use three kinds of representative magnetic fields (analytical force-free solutions, modeled solar-like force-free fields and observed non-force-free fields) to discuss on how the measurement issues such as limited field of view, instrument sensitivity and measurement error could affect the estimation of force-freeness based on observed magnetograms. Unlike previous studies that focus on discussing the effect of limited field of view or instrument sensitivity, our calculation shows that just measurement error alone can significantly influence...

  9. Neuronal bases of structural coherence in contemporary dance observation.

    Science.gov (United States)

    Bachrach, Asaf; Jola, Corinne; Pallier, Christophe

    2016-01-01

    The neuronal processes underlying dance observation have been the focus of an increasing number of brain imaging studies over the past decade. However, the existing literature mainly dealt with effects of motor and visual expertise, whereas the neural and cognitive mechanisms that underlie the interpretation of dance choreographies remained unexplored. Hence, much attention has been given to the action observation network (AON) whereas the role of other potentially relevant neuro-cognitive mechanisms such as mentalizing (theory of mind) or language (narrative comprehension) in dance understanding is yet to be elucidated. We report the results of an fMRI study where the structural coherence of short contemporary dance choreographies was manipulated parametrically using the same taped movement material. Our participants were all trained dancers. The whole-brain analysis argues that the interpretation of structurally coherent dance phrases involves a subpart (superior parietal) of the AON as well as mentalizing regions in the dorsomedial prefrontal cortex. An ROI analysis based on a similar study using linguistic materials (Pallier et al., 2011) suggests that structural processing in language and dance might share certain neural mechanisms.

  10. Forbush Decrease Prediction Based on Remote Solar Observations

    Science.gov (United States)

    Dumbovic, Mateja; Vrsnak, Bojan; Calogovic, Jasa

    2016-04-01

    We study the relation between remote observations of coronal mass ejections (CMEs), their associated solar flares and short-term depressions in the galactic cosmic-ray flux (so called Forbush decreases). Statistical relations between Forbush decrease magnitude and several CME/flare parameters are examined. In general we find that Forbush decrease magnitude is larger for faster CMEs with larger apparent width, which is associated with stronger flares that originate close to the center of the solar disk and are (possibly) involved in a CME-CME interaction. The statistical relations are quantified and employed to forecast expected Forbush decrease magnitude range based on the selected remote solar observations of the CME and associated solar flare. Several verification measures are used to evaluate the forecast method. We find that the forecast is most reliable in predicting whether or not a CME will produce a Forbush decrease with a magnitude >3 %. The main advantage of the method is that it provides an early prediction, 1-4 days in advance. Based on the presented research, an online forecast tool was developed (Forbush Decrease Forecast Tool, FDFT) available at Hvar Observatory web page: http://oh.geof.unizg.hr/FDFT/fdft.php. We acknowledge the support of Croatian Science Foundation under the project 6212 „Solar and Stellar Variability" and of European social fond under the project "PoKRet".

  11. Geomagnetic Observations for Main Field Studies

    DEFF Research Database (Denmark)

    Matzka, Jürgen; Chulliat, A.; Mandea, M.

    2010-01-01

    Direct measurements of the geomagnetic field have been made for more than 400 years, beginning with individual determinations of the angle between geographic and magnetic North. This was followed by the start of continuous time series of full vector measurements at geomagnetic observatories and t...... for magnetic field measurements on ground and in space and covers geomagnetic observatories, repeat stations, automatic observatories, satellites and historic observations. Special emphasis is laid on the global network of geomagnetic observatories....... and the beginning of geomagnetic repeat stations surveys in the 19th century. In the second half of the 20th century, true global coverage with geomagnetic field measurements was accomplished by magnetometer payloads on low-Earth-orbiting satellites. This article describes the procedures and instruments...

  12. Cutaneous hypopigmentary disorders – An observational study

    Directory of Open Access Journals (Sweden)

    Kalegowda Deepadarshan

    2016-04-01

    Full Text Available Background: Hypopigmented skin lesions is very common among people of all age groups. There are limited studies in India about evaluation of hypopigmented skin conditions. The aim of my study is to evaluate the different etiologies of cutaneous hypopigmentation. Aim: The present study was undertaken to find the relative incidence of the various disorders causing a hypopigmented lesion in a random sample of 200 cases and to study site, distribution and characteristics of the lesions. Methods: A random sample of 200 patients presenting with one or more hypopigmented lesions to the outpatient department of Dermatology, Venereology and Leprosy in KVG Medical College and Hospital, Sullia from December 2011 to January 2013 was studied. Detailed history including address and occupation with special reference to onset and duration, preceding skin conditions, exposure to chemicals, topical application and family history was taken. Various characteristics of the lesion like site, size, number, distribution, surface and sensation were studied. After this samples were taken for relevant investigations like complete hemogram, biopsy, slit skin smear, KOH mount and assessed for the causes of hypopigmented lesions. Results: In our study, most common cause with cutaneous hypopigmentation was pityriasis versicolor, seen in 52%, followed by post inflammatory hypopigmentation in 32%, pre vitiligo in 6.5%, Hansen’s disease, idiopathic guttate hypomelanosis, nevus anemicus each in 2%, Woronoff’s ring in 1.5% and miscellaneous conditions in 2% of the cases. Commonest age group affected was 21-30 years. Males (49% and females (51% were almost equally affected. Conclusion: The study concludes that various conditions comes under hypopigmentary disorders. More common in young adults. Most common scaly condition was pityriasis versicolor and non scaly condition was pre vitiligo. Proper counseling and ruling out Hansen’s disease is required to alleviate the patient

  13. Disturbance Observer Based Control of Small Unmanned Aerial Rotorcraft

    Directory of Open Access Journals (Sweden)

    Xusheng Lei

    2013-01-01

    Full Text Available As a complex system, the control performance of small unmanned aerial rotorcraft is easily affected by the dynamic model errors, measurement errors, and environment disturbances. This paper proposes a disturbance observer based control method to improve performance. The disturbance observer based control is constructed by the feedback control and a series of integral filters. The system stability can be guaranteed by the feedback control method. Furthermore, the disturbances can be estimated and eliminated quickly by the integral filters. Therefore, the control performance can be improved effectively. The control performance of the disturbance observer based control has been validated by a series of flight tests. Compared with feedback control, the disturbance observer based control yields a better tracking performance in the presence of disturbances.

  14. Structural equation modeling for observational studies

    Science.gov (United States)

    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. Observer-based Controller For Microrobot in Pulsatile Blood Flow

    OpenAIRE

    Sadelli, Lounis; Fruchard, Matthieu; Ferreira, Antoine

    2014-01-01

    International audience; We propose an observer-based controller for a magnetic microrobot immersed in the human vasculature. The drag force depends on the pulsatile blood velocity and specially acts on the microrobot dynamics. In the design of advanced control laws, the blood velocity is usually assumed to be known or set to a constant mean value to achieve the control objectives, whereas the sole robot position is measured. We prove the stability of the proposed observer-based controller com...

  16. Weight-Based Victimization toward Overweight Adolescents: Observations and Reactions of Peers

    Science.gov (United States)

    Puhl, Rebecca M.; Luedicke, Joerg; Heuer, Cheslea

    2011-01-01

    Background: Weight-based victimization has become increasingly reported among overweight youth, but little is known about adolescents' perceptions and observations of weight-based teasing and bullying. This study examined adolescents' observations of and reactions to weight-based victimization toward overweight students at school. Methods:…

  17. Solar Activity Studies using Microwave Imaging Observations

    CERN Document Server

    Gopalswamy, Nat

    2016-01-01

    We report on the status of solar cycle 24 based on polar prominence eruptions (PEs) and microwave brightness enhancement (MBE) information obtained by the Nobeyama radioheliograph. The north polar region of the Sun had near-zero field strength for more than three years (2012 to 2015) and ended only in September 2015 as indicated by the presence of polar PEs and the lack of MBE. The zero-polar-field condition in the south started only around 2013, but it ended by June 2014. Thus the asymmetry in the times of polarity reversal switched between cycle 23 and 24. The polar MBE is a good proxy for the polar magnetic field strength as indicated by the high degree of correlation between the two. The cross-correlation between the high- and low-latitude MBEs is significant for a lag of ~5.5 to 7.3 years, suggesting that the polar field of one cycle indicates the sunspot number of the next cycle in agreement with the Babcock-Leighton mechanism of solar cycles. The extended period of near-zero field in the north-polar re...

  18. Management of rheumatic chorea: an observational study

    Directory of Open Access Journals (Sweden)

    Araújo Alexandra Prufer de Queiroz Campos

    2002-01-01

    Full Text Available BACKGROUND: Rheumatic chorea (RC has recently been linked to an antibody-mediated immune mechanism. OBJECTIVE/METHOD: To verify if this knowledge reflected in management changes we conceived a descriptive study. RESULTS: The medical charts of 20 children (13 females aged 6 to 12 years (mean 8 years, diagnosed as RC from June 1996 to June 1999, were reviewed. All patients received some medical treatment. Haloperidol was the most prescribed medication (15 patients - 75 %. Sulpiride, diazepam and valproate were also used as symptomatic treatment. Imune-modulating therapy with prednisone was prescribed for seven children. The shortest course of chorea (16 days occurred in a patient treated with prednisone. CONCLUSION: Prednisone has been prescribed for rheumatic chorea besides the traditional symptomatic approach. A great variety of antichoreic drugs are being employed.

  19. A trajectory observer for camera-based underwater motion measurements

    DEFF Research Database (Denmark)

    Berg, Tor; Jouffroy, Jerome; Johansen, Vegar

    This work deals with the issue of estimating the trajectory of a vehicle or object moving underwater based on camera measurements. The proposed approach consists of a diffusion-based trajectory observer (Jouffroy and Opderbecke, 2004) processing whole segments of a trajectory at a time. Additiona......This work deals with the issue of estimating the trajectory of a vehicle or object moving underwater based on camera measurements. The proposed approach consists of a diffusion-based trajectory observer (Jouffroy and Opderbecke, 2004) processing whole segments of a trajectory at a time....... Additionally, the observer contains a Tikhonov regularizer for smoothing the estimates. Then, a method for including the camera measurements in an appropriate manner is proposed....

  20. Ground-based observations of Kepler asteroseismic targets

    CERN Document Server

    Uytterhoeven, K; Southworth, J; Randall, S; Ostensen, R; Molenda-Zakowicz, J; Marconi, M; Kurtz, D W; Kiss, L; Gutierrez-Soto, J; Frandsen, S; De Cat, P; Bruntt, H; Briquet, M; Zhang, X B; Telting, J H; Steslicki, M; Ripepi, V; Pigulski, A; Paparo, M; Oreiro, R; Choong, Ngeow Chow; Niemczura, E; Nemec, J; Narwid, A; Mathias, P; Martin-Ruiz, S; Lehman, H; Kopacki, G; Karoff, C; Jackiewicz, J; Henden, A A; Handler, G; Grigachene, A; Green, E M; Garrido, R; Machado, L Fox; Debosscher, J; Creevey, O L; Catanzaro, G; Bognar, Z; Biazzo, K; Bernabei, S

    2010-01-01

    We present the ground-based activities within the different working groups of the Kepler Asteroseismic Science Consortium (KASC). The activities aim at the systematic characterization of the 5000+ KASC targets, and at the collection of ground-based follow-up time-series data of selected promising Kepler pulsators. So far, 35 different instruments at 30 telescopes on 22 different observatories in 12 countries are in use, and a total of more than 530 observing nights has been awarded. (Based on observations made with the Isaac Newton Telescope, William Herschel Telescope, Nordic Optical Telescope, Telescopio Nazionale Galileo, Mercator Telescope (La Palma, Spain), and IAC-80 (Tenerife, Spain). Also based on observations taken at the observatories of Sierra Nevada, San Pedro Martir, Vienna, Xinglong, Apache Point, Lulin, Tautenburg, Loiano, Serra la Nave, Asiago, McDonald, Skinakas, Pic du Midi, Mauna Kea, Steward Observatory, Bialkow Observatory of the Wroclaw University, Piszkesteto Mountain Station, Observato...

  1. Power active filter control based on a resonant disturbance observer

    OpenAIRE

    Ramos Fuentes, German A.; Cortés Romero, John Alexander; Zou, Zhixiang; Costa Castelló, Ramon; Zhou, Keliang

    2015-01-01

    Active filters are power electronics devices used to eliminate harmonics from the distribution network. This article presents an active disturbance rejection control scheme for active filters. The controller is based on a linear disturbance observer combined with a disturbance rejection scheme. The parameter tuning is based on a combined pole placement and an optimal estimation based on Kalman-Bucy filter. Proposed scheme is validated through simulation and experimental work in an active filter.

  2. HOW TO DESCRIBE THE RESULTS OF OBSERVATIONAL EPIDEMIOLOGICAL STUDIES

    Directory of Open Access Journals (Sweden)

    S. A. Shal'nova

    2016-01-01

    Full Text Available Principles and fundamentals of proper presentation of observational epidemiological study results are focused. Principles of observational study publication developed by expert epidemiologists (STROBE statement are explained in detail.

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

    Science.gov (United States)

    Linden, Ariel; Yarnold, Paul R

    2016-12-01

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

  4. LMI Approach to Observer-based FD Systems Designing

    Institute of Scientific and Technical Information of China (English)

    钟麦英; 汤兵勇; 丁·史蒂芬·先春

    2001-01-01

    Increasing the robustness to the unknown uncertainty and simultaneously enhancing the sensibility to the faults is one of the important issues considered in the fault detection development. Considering the L2-gain of residual system, this paper deals the observer-based fault detection problem. By using of H∞ control theory,an LMI approach to design fault detection observer is given. A numerical example is used to illustrate the effectiveness of the proposed approach.

  5. Controller Based Observer in Switched System with Norm Bounded Uncertainty

    Directory of Open Access Journals (Sweden)

    Mongi Besbes

    2012-01-01

    Full Text Available Problem statement: This study discusses the robust stabilization of norm bounded discrete switched systems. Approach: The proposed method is using the second Lyapunov approach and the poly-quadratic function concept. The stabilization conditions are written through linear matrix inequality relations. The control law is based on a static output feedback with the use of a switched observer. The synthesis conditions of the controller are written in the form of linear matrix inequalities difficult to resolve by current numerical solvers. That’s why relaxations are proposed to mitigate the pessimism of LMI conditions obtained. Results: The poly-quadratic Lyapunov approach provides a constructive way to tackle uncertainty in the switched framework. The feasibility is illustrated by the example of discrete uncertain switched systems. Conclusion: With these results, the study of stability can be achieved for arbitrary switching laws, state-dependent, time dependent or generated by a controller. However, the implementation of the control law is possible only if the switching status is well known in real time.

  6. Likelihood based inference for partially observed renewal processes

    NARCIS (Netherlands)

    Lieshout, van M.N.M.

    2016-01-01

    This paper is concerned with inference for renewal processes on the real line that are observed in a broken interval. For such processes, the classic history-based approach cannot be used. Instead, we adapt tools from sequential spatial point process theory to propose a Monte Carlo maximum likelihoo

  7. A cooperative control algorithm for camera based observational systems.

    Energy Technology Data Exchange (ETDEWEB)

    Young, Joseph G.

    2012-01-01

    Over the last several years, there has been considerable growth in camera based observation systems for a variety of safety, scientific, and recreational applications. In order to improve the effectiveness of these systems, we frequently desire the ability to increase the number of observed objects, but solving this problem is not as simple as adding more cameras. Quite often, there are economic or physical restrictions that prevent us from adding additional cameras to the system. As a result, we require methods that coordinate the tracking of objects between multiple cameras in an optimal way. In order to accomplish this goal, we present a new cooperative control algorithm for a camera based observational system. Specifically, we present a receding horizon control where we model the underlying optimal control problem as a mixed integer linear program. The benefit of this design is that we can coordinate the actions between each camera while simultaneously respecting its kinematics. In addition, we further improve the quality of our solution by coupling our algorithm with a Kalman filter. Through this integration, we not only add a predictive component to our control, but we use the uncertainty estimates provided by the filter to encourage the system to periodically observe any outliers in the observed area. This combined approach allows us to intelligently observe the entire region of interest in an effective and thorough manner.

  8. Disturbance observer based position tracking of electro-hydraulic actuator

    Institute of Scientific and Technical Information of China (English)

    国凯; 魏建华; 田启岩

    2015-01-01

    A nonlinear controller based on an extended second-order disturbance observer is presented to track desired position for an electro-hydraulic single-rod actuator in the presence of both external disturbances and parameter uncertainties. The proposed extended second-order disturbance observer deals with not only the external perturbations, but also parameter uncertainties which are commonly regarded as lumped disturbances in previous researches. Besides, the outer position tracking loop is designed with cylinder load pressure as output; and the inner pressure control loop provides the hydraulic actuator the characteristic of a force generator. The stability of the closed-loop system is provided based on Lyapunov theory. The performance of the controller is verified through simulations and experiments. The results demonstrate that the proposed nonlinear position tracking controller, together with the extended second-order disturbance observer, gives an excellent tracking performance in the presence of parameter uncertainties and external disturbance.

  9. Underwater navigation using diffusion-based trajectory observers

    DEFF Research Database (Denmark)

    Jouffroy, Jerome; Opderbecke, Jan

    2007-01-01

    This paper addresses the issue of estimating underwater vehicle trajectories using gyro-Doppler (body-fixed velocities) and acoustic positioning signals (earth-fixed positions). The approach consists of diffusion-based observers processing a whole trajectory segment at a time, allowing the consid......This paper addresses the issue of estimating underwater vehicle trajectories using gyro-Doppler (body-fixed velocities) and acoustic positioning signals (earth-fixed positions). The approach consists of diffusion-based observers processing a whole trajectory segment at a time, allowing...... the consideration of important practical problems such as different information update rates, outages, and outliers in a very simple framework. Results of contraction theory are used to prove that the observers are convergent, i.e., stable in the incremental sense. Simulation and experimental results are presented...

  10. Lunar-based Earth observation geometrical characteristics research

    Science.gov (United States)

    Ren, Yuanzhen; Liu, Guang; Ye, Hanlin; Guo, Huadong; Ding, Yixing; Chen, Zhaoning

    2016-07-01

    As is known to all, there are various platforms for carrying sensors to observe Earth, such as automobiles, aircrafts and satellites. Nowadays, we focus on a new platform, Moon, because of its longevity, stability and vast space. These advantages make it to be the next potential platform for observing Earth, enabling us to get the consistent and global measurements. In order to get a better understanding of lunar-based Earth observation, we discuss its geometrical characteristics. At present, there are no sensors on the Moon for observing Earth and we are not able to obtain a series of real experiment data. As a result, theoretical modeling and numerical calculation are used in this paper. At first, we construct an approximate geometrical model of lunar-based Earth observation, which assumes that Earth and Moon are spheres. Next, we calculate the position of Sun, Earth and Moon based on the JPL ephemeris. With the help of positions data and geometrical model, it is possible for us to decide the location of terminator and substellar points. However, in order to determine their precise position in the conventional terrestrial coordinate system, reference frames transformations are introduced as well. Besides, taking advantages of the relative positions of Sun, Earth and Moon, we get the total coverage of lunar-based Earth optical observation. Furthermore, we calculate a more precise coverage, considering placing sensors on different positions of Moon, which is influenced by its attitude parameters. In addition, different ephemeris data are compared in our research and little difference is found.

  11. Ground-based optical observation system for LEO objects

    Science.gov (United States)

    Yanagisawa, T.; Kurosaki, H.; Oda, H.; Tagawa, M.

    2015-08-01

    We propose a ground-based optical observation system for monitoring LEO objects, which uses numerous optical sensors to cover a vast region of the sky. Its potential in terms of detection and orbital determination were examined. About 30 cm LEO objects at 1000 km altitude are detectable using an 18 cm telescope, a CCD camera and the analysis software developed. Simulations and a test observation showed that two longitudinally separate observation sites with arrays of optical sensors can identify the same objects from numerous data sets and determine their orbits precisely. The proposed system may complement or replace the current radar observation system for monitoring LEO objects, like space-situation awareness, in the near future.

  12. Context Matters: Systematic Observation of Place-Based Physical Activity.

    Science.gov (United States)

    McKenzie, Thomas L

    2016-12-01

    Physical activity is place-based, and being able to assess the number of people and their characteristics in specific locations is important both for public health surveillance and for practitioners in their design of physical activity spaces and programs. Although physical activity measurement has improved recently, many investigators avoid or are at a loss regarding the assessment of physical activity in explicit locations, especially in open environments where many people come and go in a seemingly indiscriminate fashion. Direct, systematic observation exceeds other methods in simultaneously assessing physical activity and the contexts in which it occurs. This commentary summarizes the development and use of 2 validated observation tools: the System for Observing Play and Leisure in Youth (SOPLAY) and System for Observing Play and Active Recreation in Communities (SOPARC). Their use is well supported by both behavior-analytic principles and social-ecological theory, and their methods have utility for both researchers and practitioners.

  13. Diffusion-Based Trajectory Observers with Variance Constraints

    DEFF Research Database (Denmark)

    Alcocer, Alex; Jouffroy, Jerome; Oliveira, Paulo

    Diffusion-based trajectory observers have been recently proposed as a simple and efficient framework to solve diverse smoothing problems in underwater navigation. For instance, to obtain estimates of the trajectories of an underwater vehicle given position fixes from an acoustic positioning system...... and velocity measurements from a DVL. The observers are conceptually simple and can easily deal with the problems brought about by the occurrence of asynchronous measurements and dropouts. In its original formulation, the trajectory observers depend on a user-defined constant gain that controls the level...... of smoothing and is determined by resorting to trial and error. This paper presents a methodology to choose the observer gain by taking into account a priori information on the variance of the position measurement errors. Experimental results with data from an acoustic positioning system are presented...

  14. Adaptive Observer-Based Fault Estimate for Nonlinear Systems

    Institute of Scientific and Technical Information of China (English)

    ZONG Qun; LIU Wenjing; LIU Li

    2006-01-01

    An approach for adaptive observer-based fault estimate for nonlinear system is proposed.H-infinity theory is applied to analyzing the design method and stable conditions of the adaptive observer,from which both system state and fault can be estimated.It is proved that the fault estimate error is related to the given H-infinity track performance indexes,as well as to the changing rate of the fault and the Lipschitz constant of the nonlinear item.The design steps of the adaptive observer are proposed.The simulation results show that the observer has good performance for fault estimate even when the system includes nonlinear terms,which confirms the effectiveness of the method.

  15. Parameterization of oceanic whitecap fraction based on satellite observations

    Directory of Open Access Journals (Sweden)

    M. F. M. A. Albert

    2015-08-01

    Full Text Available In this study the utility of satellite-based whitecap fraction (W values for the prediction of sea spray aerosol (SSA emission rates is explored. More specifically, the study is aimed at improving the accuracy of the sea spray source function (SSSF derived by using the whitecap method through the reduction of the uncertainties in the parameterization of W by better accounting for its natural variability. The starting point is a dataset containing W data, together with matching environmental and statistical data, for 2006. Whitecap fraction W was estimated from observations of the ocean surface brightness temperature TB by satellite-borne radiometers at two frequencies (10 and 37 GHz. A global scale assessment of the data set to evaluate the wind speed dependence of W revealed a quadratic correlation between W and U10, as well as a relatively larger spread in the 37 GHz data set. The latter could be attributed to secondary factors affecting W in addition to U10. To better visualize these secondary factors, a regional scale assessment over different seasons was performed. This assessment indicates that the influence of secondary factors on W is for the largest part imbedded in the exponent of the wind speed dependence. Hence no further improvement can be expected by looking at effects of other factors on the variation in W explicitly. From the regional analysis, a new globally applicable quadratic W(U10 parameterization was derived. An intrinsic correlation between W and U10 that could have been introduced while estimating W from TB was determined, evaluated and presumed to lie within the error margins of the newly derived W(U10 parameterization. The satellite-based parameterization was compared to parameterizations from other studies and was applied in a SSSF to estimate the global SSA emission rate. The thus obtained SSA production for 2006 of 4.1 × 1012 kg is within previously reported estimates. While recent studies that account for

  16. Forbush Decrease Prediction Based on the Remote Solar Observations

    OpenAIRE

    Dumbovic, Mateja; Vrsnak, Bojan; Calogovic, Jasa

    2015-01-01

    We employ remote observations of coronal mass ejections (CMEs) and the associated solar flares to forecast the CME-related Forbush decreases, i.e., short-term depressions in the galactic cosmic-ray flux. The relationship between the Forbush effect at the Earth and remote observations of CMEs and associated solar flares is studied via a statistical analysis. Relationships between Forbush decrease magnitude and several CME/flare parameters was found, namely the initial CME speed, apparent width...

  17. Empirical study of sensor observation services server instances

    CERN Document Server

    Tamayo, Alain; Granell, Carlos; Huerta, Joaquín; 10.1007/978-3-642-19789-5_10

    2011-01-01

    The number of Sensor Observation Service (SOS) instances available online has been increasing in the last few years. The SOS specification standardises interfaces and data formats for exchanging sensor-related in-formation between information providers and consumers. SOS in conjunction with other specifications in the Sensor Web Enablement initiative, at-tempts to realise the Sensor Web vision, a worldwide system where sensor networks of any kind are interconnected. In this paper we present an empirical study of actual instances of servers implementing SOS. The study focuses mostly in which parts of the specification are more frequently included in real implementations, and how exchanged messages follows the structure defined by XML Schema files. Our findings can be of practical use when implementing servers and clients based on the SOS specification, as they can be optimized for common scenarios.

  18. Virtual estimator for piecewise linear systems based on observability analysis.

    Science.gov (United States)

    Morales-Morales, Cornelio; Adam-Medina, Manuel; Cervantes, Ilse; Vela-Valdés, Luis G; Beltrán, Carlos Daniel García

    2013-02-27

    This article proposes a virtual sensor for piecewise linear systems based on observability analysis that is in function of a commutation law related with the system's outpu. This virtual sensor is also known as a state estimator. Besides, it presents a detector of active mode when the commutation sequences of each linear subsystem are arbitrary and unknown. For the previous, this article proposes a set of virtual estimators that discern the commutation paths of the system and allow estimating their output. In this work a methodology in order to test the observability for piecewise linear systems with discrete time is proposed. An academic example is presented to show the obtained results.

  19. Virtual Estimator for Piecewise Linear Systems Based on Observability Analysis

    Science.gov (United States)

    Morales-Morales, Cornelio; Adam-Medina, Manuel; Cervantes, Ilse; Vela-Valdés and, Luis G.; García Beltrán, Carlos Daniel

    2013-01-01

    This article proposes a virtual sensor for piecewise linear systems based on observability analysis that is in function of a commutation law related with the system's outpu. This virtual sensor is also known as a state estimator. Besides, it presents a detector of active mode when the commutation sequences of each linear subsystem are arbitrary and unknown. For the previous, this article proposes a set of virtual estimators that discern the commutation paths of the system and allow estimating their output. In this work a methodology in order to test the observability for piecewise linear systems with discrete time is proposed. An academic example is presented to show the obtained results. PMID:23447007

  20. Underwater vehicle trajectory estimation using contracting PDE-based observers

    DEFF Research Database (Denmark)

    Jouffroy, Jerome; Opderbecke, Jan

    This paper addresses the issue of estimating underwater vehicle trajectories using Gyro-Doppler (body-fixed velocities) and acoustic signals (earth-fixed positions). The approach consists of diffusion-based observers processing a whole trajectory segment at a time, allowing to consider important...... practical problems such as different information update rates, outages, and outliers in a very simple framework. Results of (Lohmiller and Slotine, 1999) are used to prove that the observers are contracting, i.e. convergent in the sense of contraction analysis. Simulation and experimental results...

  1. Observer-based H∞ control over packet dropping networks

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A new controller design problem of networked control systems with packet dropping is proposed. Depending on the place that the observer is put in the system, the network control systems with packet dropping are modeled as stochastic systems with the random variables satisfying the Bernoulli random binary distribution. The observer-based controller is designed to stabilize the networked system in the sense of mean square, and the prescribed H∞ disturbance attenuation level is achieved. The controller design problem is formulated as the feasibility of the convex optimization problem, which can be solved by a linear matrix inequality (LMI) approach. Numerical examples illustrate the effectiveness of the proposed methods.

  2. Study on Speed Observer for Permanent Magnet Synchronous Servo Motor Based on Sliding Mode Variable Structure MRAS%基于滑模变结构MARS的PMSM速度观测器研究

    Institute of Scientific and Technical Information of China (English)

    潘文英; 屈百达; 徐保国

    2013-01-01

    For studying sensorless speed identification,a speed observer was constructed based on the theory of model reference adaptive system (MRAS) by stator flux reference model and rotor flux adjustable model of permanent magnet synchronous servo motor (PMSM). At the same time,in view of the problem existed in servo system including parametric variation and disturbance,a new ob-serve method was proposed. Sliding mode variable structure control was used to construct self-adaptation principle of rotating speed, and the sigmoid function was introduced to eliminate the common dithering of sliding mode control. By MATLAB/Simulink simulation, it is proved using sliding mode variable structure MRAS speed observer,speed identification can be effectively realized.%  研究无速度传感器速度的辨识,利用永磁同步电机的定子磁链参考模型和可调模型,构造基于模型参考自适应控制的速度观测器。同时针对伺服系统中存在的参数变化、扰动等问题,提出一种新型的观测方法。运用滑模变结构控制来构造转速估计自适应律,并引入Sigmoid函数来克服滑模控制引起的抖振。通过MATLAB/Simulink仿真,表明滑模变结构MARS速度观测器能够更好地实现速度的辨识。

  3. Observational and interventional study design types; an overview

    OpenAIRE

    Thiese, Matthew S.

    2014-01-01

    The appropriate choice in study design is essential for the successful execution of biomedical and public health research. There are many study designs to choose from within two broad categories of observational and interventional studies. Each design has its own strengths and weaknesses, and the need to understand these limitations is necessary to arrive at correct study conclusions. Observational study designs, also called epidemiologic study designs, are often retrospective and are used...

  4. The relationship between observer-based toxicity scoring and patient assessed symptom severity after treatment for head and neck cancer. A correlative cross sectional study of the DAHANCA toxicity scoring system and the EORTC quality of life questionnaires

    DEFF Research Database (Denmark)

    Bonde Jensen, Anders; Grau, Cai; Jensen, Kenneth

    2006-01-01

    BACKGROUND AND PURPOSE: Morbidity is an important issue in cancer       research. The observer-based toxicity scoring system used by DAHANCA (the       Danish head and neck cancer study group) has proved itself sensitive to       differences in toxicity in a large randomised study, but like other......       toxicity scoring systems it has not been formally validated. Conversely,       the EORTC quality of life questionnaire (QLQ) has been validated as a tool       for collecting information about the consequences of disease and treatment       on the well being of cancer patients. The purpose of this study...... toxicity scoring system       and the EORTC QLQ correlated with several clinical endpoints. The       conceptually similar endpoints of the two methods correlated       significantly. The objective endpoints of the DAHANCA scoring system were       only correlated with quality of life endpoints to a very...

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

    Science.gov (United States)

    2016-09-28

    demanding environments in which they work and the excessive lifting and reaching involved in AE tasks. This study characterized the ergonomic risks in...AFRL-SA-WP-TR-2016-0014 Characterizing Musculoskeletal Injury among Aeromedical Evacuation Personnel: An Observational Study ...March 2016 4. TITLE AND SUBTITLE Characterizing Musculoskeletal Injury among Aeromedical Evacuation Personnel: An Observational Study 5a

  6. Observational studies and the difficult quest for causality

    DEFF Research Database (Denmark)

    Lipsitch, Marc; Jha, Ayan; Simonsen, Lone

    2017-01-01

    be answered once the vaccine is in use, from observational studies. However, such studies are inherently at risk for bias. Using a causal framework and illustrating with examples, we review newer approaches to detecting and avoiding confounding and selection bias in three major classes of observational study...

  7. Observer-Based Fuel Control Using Oxygen Measurement

    DEFF Research Database (Denmark)

    Andersen, Palle; Bendtsen, Jan Dimon; Mortensen, Jan Henrik

    is constructed and validated against data obtained at the plant. A Kalman filter based on measurements of combustion air flow led into the furnace and oxygen concentration in the flue gas is designed to estimate the actual coal flow. With this estimate, it becomes possible to close an inner loop around the coal......This report describes an attempt to improve the existing control af coal mills used at the Danish power plant Nordjyllandsværket Unit 3. The coal mills are not equipped with coal flow sensors; thus an observer-based approach is investigated. A nonlinear differential equation model of the boiler...

  8. Disturbance observer based current controller for vector controlled IM drives

    DEFF Research Database (Denmark)

    Teodorescu, Remus; Dal, Mehmet

    2008-01-01

    In order to increase the accuracy of the current control loop, usually, well known parameter compensation and/or cross decoupling techniques are employed for advanced ac drives. In this paper, instead of using these techniques an observer-based current controller is proposed for vector controlled...... coupling effects and increase robustness against parameters change without requiring any other compensation strategies. The experimental implementation results are provided to demonstrate validity and performance of the proposed control scheme.......In order to increase the accuracy of the current control loop, usually, well known parameter compensation and/or cross decoupling techniques are employed for advanced ac drives. In this paper, instead of using these techniques an observer-based current controller is proposed for vector controlled...

  9. Earth Observation Satellites Scheduling Based on Decomposition Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    Feng Yao

    2010-11-01

    Full Text Available A decomposition-based optimization algorithm was proposed for solving Earth Observation Satellites scheduling problem. The problem was decomposed into task assignment main problem and single satellite scheduling sub-problem. In task assignment phase, the tasks were allocated to the satellites, and each satellite would schedule the task respectively in single satellite scheduling phase. We adopted an adaptive ant colony optimization algorithm to search the optimal task assignment scheme. Adaptive parameter adjusting strategy and pheromone trail smoothing strategy were introduced to balance the exploration and the exploitation of search process. A heuristic algorithm and a very fast simulated annealing algorithm were proposed to solve the single satellite scheduling problem. The task assignment scheme was valued by integrating the observation scheduling result of multiple satellites. The result was responded to the ant colony optimization algorithm, which can guide the search process of ant colony optimization. Computation results showed that the approach was effective to the satellites observation scheduling problem.

  10. Verifying Embedded Systems using Component-based Runtime Observers

    DEFF Research Database (Denmark)

    Guan, Wei; Marian, Nicolae; Angelov, Christo K.

    Formal verification methods, such as exhaustive model checking, are often infeasible because of high computational complexity. Runtime observers (monitors) provide an alternative, light-weight verification method, which offers a non-exhaustive yet feasible approach to monitoring system behavior...... against formally specified properties. This paper presents a component-based design method for runtime observers, which are configured from instances of prefabricated reusable components---Predicate Evaluator (PE) and Temporal Evaluator (TE). The PE computes atomic propositions for the TE; the latter...... is a reconfigurable component processing a data structure, representing the state transition diagram of a non-deterministic state machine, i.e. a Buchi automaton derived from a system property specified in Linear Temporal Logic (LTL). Observer components have been implemented using design models and design patterns...

  11. An Efficient Optical Observation Ground Network is the Fundamental basis for any Space Based Debris Observation Segment

    Science.gov (United States)

    Cibin, L.; Chiarini, M.; Annoni, G.; Milani, A.; Bernardi, F.; Dimare, L.; Valsecchi, G.; Rossi, A.; Ragazzoni, R.; Salinari, P.

    2013-08-01

    A matter which is strongly debated in the SSA Community, concerns the observation of Space Debris from Space [1]. This topic has been preliminary studied by our Team for LEO, MEO and GEO orbital belts, allowing to remark a fundamental concept, residing in the fact that to be suitable to provide a functionality unavailable from ground in a cost to performance perspective, any Space Based System must operate in tight collaboration with an efficient Optical Ground Observation Network. In this work an analysis of the different functionalities which can be implemented with this approach for every orbital belt is illustrated, remarking the different achievable targets in terms of population size as a function of the observed orbits. Further, a preliminary definition of the most interesting missions scenarios, together with considerations and assessments on the observation strategy and P/L characteristics are presented.

  12. Information-based physics: an observer-centric foundation

    Science.gov (United States)

    Knuth, Kevin H.

    2014-01-01

    It is generally believed that physical laws, reflecting an inherent order in the universe, are ordained by nature. However, in modern physics the observer plays a central role raising questions about how an observer-centric physics can result in laws apparently worthy of a universal nature-centric physics. Over the last decade, we have found that the consistent apt quantification of algebraic and order-theoretic structures results in calculi that possess constraint equations taking the form of what are often considered to be physical laws. I review recent derivations of the formal relations among relevant variables central to special relativity, probability theory and quantum mechanics in this context by considering a problem where two observers form consistent descriptions of and make optimal inferences about a free particle that simply influences them. I show that this approach to describing such a particle based only on available information leads to the mathematics of relativistic quantum mechanics as well as a description of a free particle that reproduces many of the basic properties of a fermion. The result is an approach to foundational physics where laws derive from both consistent descriptions and optimal information-based inferences made by embedded observers.

  13. Parameter estimation for the subcritical Heston model based on discrete time observations

    OpenAIRE

    2014-01-01

    We study asymptotic properties of some (essentially conditional least squares) parameter estimators for the subcritical Heston model based on discrete time observations derived from conditional least squares estimators of some modified parameters.

  14. Observational studies of regions of massive star formation

    Science.gov (United States)

    Cooper, Heather Danielle Blythe

    2013-03-01

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

  15. An Observational Study of Entrainment Rate in Deep Convection

    Directory of Open Access Journals (Sweden)

    Xiaohao Guo

    2015-09-01

    Full Text Available 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. In addition, 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.

  16. Kalman Based Finite State Controller for Partially Observable Domains

    Directory of Open Access Journals (Sweden)

    H. Levent Akin

    2008-11-01

    Full Text Available A real world environment is often partially observable by the agents either because of noisy sensors or incomplete perception. Moreover, it has continuous state space in nature, and agents must decide on an action for each point in internal continuous belief space. Consequently, it is convenient to model this type of decisionmaking problems as Partially Observable Markov Decision Processes (POMDPs with continuous observation and state space. Most of the POMDP methods whether approximate or exact assume that the underlying world dynamics or POMDP parameters such as transition and observation probabilities are known. However, for many real world environments it is very difficult if not impossible to obtain such information. We assume that only the internal dynamics of the agent, such as the actuator noise, interpretation of the sensor suite, are known. Using these internal dynamics, our algorithm, namely Kalman Based Finite State Controller (KBFSC, constructs an internal world model over the continuous belief space, represented by a finite state automaton. Constructed automaton nodes are points of the continuous belief space sharing a common best action and a common uncertainty level. KBFSC deals with continuous Gaussian-based POMDPs. It makes use of Kalman Filter for belief state estimation, which also is an efficient method to prune unvisited segments of the belief space and can foresee the reachable belief points approximately calculating the horizon N policy. KBFSC does not use an "explore and update" approach in the value calculation as TD-learning. Therefore KBFSC does not have an extensive exploration-exploitation phase. Using the MDP case reward and the internal dynamics of the agent, KBFSC can automatically construct the finite state automaton (FSA representing the approximate optimal policy without the need for discretization of the state and observation space. Moreover, the policy always converges for POMDP problems.

  17. Observation of pentaquark states and perspectives of further studies

    CERN Document Server

    Shen, Cheng-Ping

    2015-01-01

    In this invited short "news and views", we review very briefly the history of pentaquark studies and the recent observations of the tetraquark and pentaquark states. We also discuss further experimental studies such as at Belle-II.

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

    Directory of Open Access Journals (Sweden)

    Elisa De Stefani

    Full Text Available 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.

  19. Mooring System of Ocean Turbulence Observation Based on Submerged Buoy

    Institute of Scientific and Technical Information of China (English)

    SONG Da-lei; SUN Jing-jing; XUE Bing; JIANG Qian-li; WU Bing-wei

    2013-01-01

    A comparison experiment has been taken in the Kiaochow Bay between a newly designed mooring turbulence observation instrument (MTOI) and microstructure profiler MSS60 made by Sea & Sun.The whole observing system is based on a submerged buoy,in which the turbulence observation instrument is embedded,with a streamline-shape floating body,which is made of buoyancy material of glass microsphere.For the movement of seawater and the cable shaking strongly anytime influence the behaviors of the floating body,the accelerate sensors are used for the vibration measurement in the instrument together with the shear probe sensor.Both the vibration data and the shear data are acquired by the instrument at the same time.During data processing,the vibration signals can be removed and leave the shear data which we really need.In order to prove the reliability of the new turbulence instrument MTOI,a comparison experiment was designed.The measuring conditions are the same both in time and space.By this way,the two groups of data are comparable.In this paper,the conclusion gives a good similarity of 0.93 for the two groups of shear data in dissipation rate.The processing of the data acquired by MTOI is based on the cross-spectrum analysis,and the dissipation rate of it matches the Nasmyth spectrum well.

  20. Observers change their target template based on expected context.

    Science.gov (United States)

    Bravo, Mary J; Farid, Hany

    2016-04-01

    Previous studies have shown that when observers search repeatedly for a target in a particular context, they may develop a target template that is biased for that context. Because the same target may appear in multiple contexts, we wondered whether observers are able to develop multiple templates for the same target, with each template biased for a particular context. In a series of behavioral experiments, we show that observers can learn multiple target templates for a single target and that they can voluntarily switch among these templates depending on the context they expect to see. Our results suggest that these biased templates may coexist with an unbiased representation of the target, provided they are learned first.

  1. Observer Based Fault Detection and Moisture Estimating in Coal Mill

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Mataji, Babak

    2008-01-01

    In this paper an observer-based method for detecting faults and estimating moisture content in the coal in coal mills is presented. Handling of faults and operation under special conditions, such as high moisture content in the coal, are of growing importance due to the increasing requirements to......In this paper an observer-based method for detecting faults and estimating moisture content in the coal in coal mills is presented. Handling of faults and operation under special conditions, such as high moisture content in the coal, are of growing importance due to the increasing...... requirements to the general performance of power plants. Detection  of faults and moisture content estimation are consequently of high interest in the handling of the problems caused by faults and moisture content. The coal flow out of the mill is the obvious variable to monitor, when detecting non-intended drops in the coal...... flow out of the coal mill. However, this variable is not measurable. Another estimated variable is the moisture content, which is only "measurable" during steady-state operations of the coal mill. Instead, this paper suggests a method where these unknown variables are estimated based on a simple energy...

  2. Observational Selection Effects with Ground-based Gravitational Wave Detectors

    Science.gov (United States)

    Chen, Hsin-Yu; Essick, Reed; Vitale, Salvatore; Holz, Daniel; Katsavounidis, Erik

    2017-01-01

    Ground-based interferometers are not perfectly all-sky instruments, and it is important to account for their behavior when considering the distribution of detected events. In particular, the LIGO detectors are most sensitive to sources above North America and the Indian Ocean and, as the Earth rotates, the sensitive regions are swept across the sky. However, because the detectors do not acquire data uniformly over time, there is a net bias on detectable sources' right ascensions. Both LIGO detectors preferentially collect data during their local night; it is more than twice as likely to be local midnight than noon when both detectors are operating. We discuss these selection effects and how they impact LIGO's observations and electromagnetic follow-up. These effects can inform electromagnetic follow-up activities and optimization, including the possibility of directing observations even before gravitational-wave events occur.

  3. Longitudinal tire force estimation based on sliding mode observer

    Energy Technology Data Exchange (ETDEWEB)

    El Hadri, A.; Cadiou, J.C.; M' Sirdi, N.K. [Versailles Univ., Paris (France). Lab. de Robotique; Beurier, G.; Delanne, Y. [Lab. Central des Ponts, Centre de Nantes (France)

    2001-07-01

    This paper presents an estimation method for vehicle longitudinal dynamics, particularly the tractive/braking force. The estimation can be used to detect a critical driving situation to improve security. It can be used also in several vehicle control systems. The main characteristics of the vehicle longitudinal dynamics were taken into account in the model used to design an observer and computer simulations. The state variables are the angular wheel velocity, vehicle velocity and the longitudinal tire force. The proposed differential equation of the tractive/braking force is derived using the concept of relaxation length. The observer designed is based on the sliding mode approach using only the angular wheel velocity measurement. The proposed method of estimation is verified through a one-wheel simulation model with a ''Magic formula'' tire model. Simulations results show an excellent reconstruction of the tire force. (orig.)

  4. Virtual Estimator for Piecewise Linear Systems Based on Observability Analysis

    Directory of Open Access Journals (Sweden)

    Ilse Cervantes

    2013-02-01

    Full Text Available This article proposes a virtual sensor for piecewise linear systems based on observability analysis that is in function of a commutation law related with the system’s outpu. This virtual sensor is also known as a state estimator. Besides, it presents a detector of active mode when the commutation sequences of each linear subsystem are arbitrary and unknown. For the previous, this article proposes a set of virtual estimators that discern the commutation paths of the system and allow estimating their output. In this work a methodology in order to test the observability for piecewise linear systems with discrete time is proposed. An academic example is presented to show the obtained results.

  5. Disturbance observer based hierarchical control of coaxial-rotor UAV.

    Science.gov (United States)

    Mokhtari, M Rida; Cherki, Brahim; Braham, Amal Choukchou

    2017-03-01

    This paper propose an hierarchical controller based on a new disturbance observer with finite time convergence (FTDO) to solve the path tracking of a small coaxial-rotor-typs Unmanned Aerial Vehicles (UAVs) despite of unknown aerodynamic efforts. The hierarchical control technique is used to separate the flight control problem into an inner loop that controls attitude and an outer loop that controls the thrust force acting on the vehicle. The new disturbance observer with finite time convergence is intergated to online estimate the unknown uncertainties and disturbances and to actively compensate them in finite time.The analysis further extends to the design of a control law that takes the disturbance estimation procedure into account. Numerical simulations are carried out to demonstrate the efficiency of the proposed control strategy.

  6. Influence of treatment with alendronate on the speed of sound, an ultrasound parameter, of the calcaneus in postmenopausal Japanese women with osteoporosis: a clinical practice-based observational study

    Directory of Open Access Journals (Sweden)

    Iwamoto J

    2012-06-01

    Full Text Available Jun Iwamoto,1 Tetsuya Takada,2 Yoshihiro Sato,3 Hideo Matsumoto11Institute for Integrated Sports Medicine, Keio University School of Medicine, Tokyo, 2Department of Internal Medicine, Hiyoshi Medical Clinic, Kanagawa, 3Department of Neurology, Mitate Hospital, Fukuoka, JapanPurpose: The influence of alendronate (ALN treatment on the quantitative ultrasound parameters of the calcaneus remains to be established in Japanese patients. The aim of the present clinical practice-based observational study was to examine the influence of ALN treatment for 1 year on the speed of sound (SOS of the calcaneus and bone turnover markers in postmenopausal Japanese women with osteoporosis.Patients and methods: Forty-five postmenopausal Japanese women with osteoporosis who had received treatment with ALN for more than 1 year were enrolled in the study. The SOS and bone turnover markers were monitored over 1 year of ALN treatment.Results: The urinary levels of cross-linked N-terminal telopeptides of type I collagen and serum levels of alkaline phosphatase decreased significantly from the baseline values (–44.9% at 3 months and –22.2% at 12 months, respectively. The SOS increased modestly, but significantly, from the baseline value (0.6% at both 6 and 12 months. The percentage decrease in the urinary levels of cross-linked N-terminal telopeptides of type I collagen at 3 months was significantly correlated with the percentage increase in the SOS only at 6 months (correlation coefficient, 0.299.Conclusion: The present study confirmed that ALN treatment suppressed bone turnover, producing a clinically significant increase in the SOS of the calcaneus in postmenopausal Japanese women with osteoporosis.Keywords: postmenopausal osteoporosis, quantitative ultrasound (QUS, SOS, bone turnover, biochemical markers

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

    Science.gov (United States)

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

    2016-05-22

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

  8. Explaining the effects of a multifaceted intervention to improve inpatient care in rural Kenyan hospitals -- interpretation based on retrospective examination of data from participant observation, quantitative and qualitative studies

    Directory of Open Access Journals (Sweden)

    English Mike

    2011-12-01

    Full Text Available Abstract Background We have reported the results of a cluster randomized trial of rural Kenyan hospitals evaluating the effects of an intervention to introduce care based on best-practice guidelines. In parallel work we described the context of the study, explored the process and perceptions of the intervention, and undertook a discrete study on health worker motivation because this was felt likely to be an important contributor to poor performance in Kenyan public sector hospitals. Here, we use data from these multiple studies and insights gained from being participants in and observers of the intervention process to provide our explanation of how intervention effects were achieved as part of an effort to better understand implementation in low-income hospital settings. Methods Initial hypotheses were generated to explain the variation in intervention effects across place, time, and effect measure (indicator based on our understanding of theory and informed by our implementation experience and participant observations. All data sources available for hospitals considered as cases for study were then examined to determine if hypotheses were supported, rejected, or required modification. Data included transcriptions of interviews and group discussions, field notes and that from the detailed longitudinal quantitative investigation. Potentially useful explanatory themes were identified, discussed by the implementing and research team, revised, and merged as part of an iterative process aimed at building more generic explanatory theory. At the end of this process, findings were mapped against a recently reported comprehensive framework for implementation research. Results A normative re-educative intervention approach evolved that sought to reset norms and values concerning good practice and promote 'grass-roots' participation to improve delivery of correct care. Maximal effects were achieved when this strategy and external support supervision helped

  9. Observational Selection Effects with Ground-based Gravitational Wave Detectors

    Science.gov (United States)

    Chen, Hsin-Yu; Essick, Reed; Vitale, Salvatore; Holz, Daniel E.; Katsavounidis, Erik

    2017-01-01

    Ground-based interferometers are not perfect all-sky instruments, and it is important to account for their behavior when considering the distribution of detected events. In particular, the LIGO detectors are most sensitive to sources above North America and the Indian Ocean, and as the Earth rotates, the sensitive regions are swept across the sky. However, because the detectors do not acquire data uniformly over time, there is a net bias on detectable sources’ right ascensions. Both LIGO detectors preferentially collect data during their local night; it is more than twice as likely to be local midnight than noon when both detectors are operating. We discuss these selection effects and how they impact LIGO’s observations and electromagnetic (EM) follow-up. Beyond galactic foregrounds associated with seasonal variations, we find that equatorial observatories can access over 80% of the localization probability, while mid-latitudes will access closer to 70%. Facilities located near the two LIGO sites can observe sources closer to their zenith than their analogs in the south, but the average observation will still be no closer than 44° from zenith. We also find that observatories in Africa or the South Atlantic will wait systematically longer before they can begin observing compared to the rest of the world though, there is a preference for longitudes near the LIGOs. These effects, along with knowledge of the LIGO antenna pattern, can inform EM follow-up activities and optimization, including the possibility of directing observations even before gravitational-wave events occur.

  10. Meta-analysis of observational epidemiological studies: a review.

    OpenAIRE

    Jones, D R

    1992-01-01

    Meta-analyses (integration of findings by quantitative analyses of results of individual studies) are already widely used in the psychological and educational sciences and in the pooling of clinical trial results. Examples of the application of such techniques to the results of observational epidemiological studies are now proliferating. In this paper meta-analysis of the results of observational epidemiological studies is reviewed. Uncritical adoption of techniques used in pooled analyses of...

  11. Simulation Study Of Early Afterglows Observed With Swift

    Science.gov (United States)

    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.

  12. Acceptance of a reusable self-injection device for recombinant human growth hormone: final data from a questionnaire-based, cross-sectional, international, multicenter, observational study in pediatric patients

    Science.gov (United States)

    Schnabel, Dirk; Partsch, Carl-Joachim; Houang, Muriel; Ehtisham, Sarah; Johnstone, Helen; Zabransky, Markus; Kiess, Wieland

    2016-01-01

    Background A questionnaire-based survey was conducted to assess attitudes toward a reusable self-injection system (SurePal™) among pediatric patients with growth disturbances who were prescribed treatment with Omnitrope® within routine clinical practice. Methods This was a multicenter, observational study, incorporated into the noninterventional PAtients TReated with Omnitrope® (PATRO) Children study. Included subjects, or their caregivers, completed a questionnaire on the following five main areas: attractiveness of SurePal™, training received, using the device, the low drug wastage system, and experience versus other devices used previously (pretreated patients). Responses were based on a 5-point scale, with 2 being the best possible outcome and −2 the worst possible outcome. Results In total, 550 patients were included in this study (338 from France, 169 from Germany, and 43 from the UK). The mean age ± standard deviation of participants was 10.8±3.5 years; the majority (57%) were male and growth hormone treatment naïve (88%). Almost half (49.8%) of children prepared their SurePal™ for injection themselves and 45.5% performed injections themselves. As patients progressed into their teens, the majority (≥75%) favored preparing SurePal™ and performing injections themselves, rather than seeking assistance. The attractiveness of SurePal™ was rated as excellent/good by 84.7% of patients overall; this rating was similarly high (≥79%) across countries and age-groups. Preparing (88.8%) and using (83.3%) SurePal™ were rated as very easy/easy by most patients; these ratings were similarly high, irrespective of country or age-group. The dose-memory function was rated as very helpful/helpful by 66.2% of patients. Among 246 patients who reported using the low drug-waste feature, 87.4% found it helpful. Among pretreated patients (n=64), 78.2% reported that SurePal™ was much better/better than their previous device. Conclusion These data confirm the

  13. Observation

    Science.gov (United States)

    Patell, Hilla

    2016-01-01

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

  14. The EULAR Study Group for Registers and Observational Drug Studies

    DEFF Research Database (Denmark)

    Kearsley-Fleet, Lianne; Závada, Jakub; Hetland, Merete Lund;

    2015-01-01

    OBJECTIVE: Under the auspices of the European League Against Rheumatism (EULAR), a study group of investigators representing European biologic DMARD (bDMARD) registers was convened. The purpose of this initial assessment was to collect and compare a cross section of patient characteristics......-morbidities, were collected and compared across 14 European bDMARD registers. RESULTS: A total of 5320 patients were included. Half the registers had restricted recruitment to certain bDMARDs during the study year. All registers` collected data on age, gender, disease duration, seropositivity for IgM-RF and 28...

  15. Calculating track-based observables for the LHC.

    Science.gov (United States)

    Chang, Hsi-Ming; Procura, Massimiliano; Thaler, Jesse; Waalewijn, Wouter J

    2013-09-06

    By using observables that only depend on charged particles (tracks), one can efficiently suppress pileup contamination at the LHC. Such measurements are not infrared safe in perturbation theory, so any calculation of track-based observables must account for hadronization effects. We develop a formalism to perform these calculations in QCD, by matching partonic cross sections onto new nonperturbative objects called track functions which absorb infrared divergences. The track function Ti(x) describes the energy fraction x of a hard parton i which is converted into charged hadrons. We give a field-theoretic definition of the track function and derive its renormalization group evolution, which is in excellent agreement with the pythia parton shower. We then perform a next-to-leading order calculation of the total energy fraction of charged particles in e+ e-→ hadrons. To demonstrate the implications of our framework for the LHC, we match the pythia parton shower onto a set of track functions to describe the track mass distribution in Higgs plus one jet events. We also show how to reduce smearing due to hadronization fluctuations by measuring dimensionless track-based ratios.

  16. Possible satellite-based observations of the 1997 Leonid meteoroids

    Energy Technology Data Exchange (ETDEWEB)

    Pongratz, M.B.; Carlos, R.C.; Cayton, T.

    1998-12-01

    The Block IIA GPS satellites are equipped with a sensor designed to detect electromagnetic transients. Several phenomena will produce triggers in this sensor. They include earth-based electromagnetic transients such as lightning and two space-based phenomena--deep dielectric discharge and meteoroid or hyper-velocity micro-gram particle impact (HMPI). Energetic electrons in the GPS environment cause the deep dielectric charging. HMPIs cause triggers through the transient electric fields generated by the ejecta plasma. During the 1997 Leonid passage the energetic particle fluxes were very low. In the presence of such low fluxes the typical median trigger rate is 20 per minute with a standard deviation of about 20 per minute. Between 0800 UT and 1200 UT on November 17, 1997, the sensor on a specially configured satellite observed trigger rates more than 10 sigma above the nominal median rate. Sensors on other Block IIA GPS satellites also observed excess triggers during November. Detection is enhanced when the sensor antenna is oriented into the Leonid radiant. While many questions persist the authors feel that it is likely that the excess events during the November interval were caused by the close approach of the satellites to the Leonid meteoroid path.

  17. Satellite Type Estination from Ground-based Photometric Observation

    Science.gov (United States)

    Endo, T.; Ono, H.; Suzuki, J.; Ando, T.; Takanezawa, T.

    2016-09-01

    The optical photometric observation is potentially a powerful tool for understanding of the Geostationary Earth Orbit (GEO) objects. At first, we measured in laboratory the surface reflectance of common satellite materials, for example, Multi-layer Insulation (MLI), mono-crystalline silicon cells, and Carbon Fiber Reinforced Plastic (CFRP). Next, we calculated visual magnitude of a satellite by simplified shape and albedo. In this calculation model, solar panels have dimensions of 2 by 8 meters, and the bus area is 2 meters squared with measured optical properties described above. Under these conditions, it clarified the brightness can change the range between 3 and 4 magnitudes in one night, but color index changes only from 1 to 2 magnitudes. Finally, we observed the color photometric data of several GEO satellites visible from Japan multiple times in August and September 2014. We obtained that light curves of GEO satellites recorded in the B and V bands (using Johnson filters) by a ground-base optical telescope. As a result, color index changed approximately from 0.5 to 1 magnitude in one night, and the order of magnitude was not changed in all cases. In this paper, we briefly discuss about satellite type estimation using the relation between brightness and color index obtained from the photometric observation.

  18. The Platform Design of Space-based Optical Observations of Space Debris

    Science.gov (United States)

    Bing-er, Chen; Jian-ning, Xiong

    2017-01-01

    The basic method to design a platform for the space-based optical observations of space debris is introduced. The observation schemes of GEO (geosynchronous equatorial orbit) and LEO (low Earth orbit) debris are given respectively, including the orbital parameters of platforms and the pointing of telescopes, etc. The debris studied here are all taken from the foreign catalog. According to the real orbits of space debris, the observational results of different schemes are simulated. By studying the single platform, the optimal observing altitude for the GEO debris and the optimal telescope's deflection angles at different altitudes for the LEO debris are given. According to these, the multi-platform observation networks are designed. By analyzing the advantages and disadvantages of different schemes, it can provide a reference for the application of space-based optical observations of space debris

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

    Science.gov (United States)

    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…

  20. Cost-efficient measurement strategies for posture observations based on video recordings.

    Science.gov (United States)

    Mathiassen, Svend Erik; Liv, Per; Wahlström, Jens

    2013-07-01

    Assessment of working postures by observation is a common practice in ergonomics. The present study investigated whether monetary resources invested in a video-based posture observation study should preferably be spent in collecting many video recordings of the work and have them observed once by one observer, or in having multiple observers rate postures repeatedly from fewer videos. The study addressed this question from a practitioner's perspective by focusing two plausible scenarios: documenting the mean exposure of one individual, and of a specific occupational group. Using a data set of observed working postures among hairdressers, empirical values of posture variability, observer variability, and costs for recording and observing one video were entered into equations expressing the total cost of data collection and the information (defined as 1/SD) provided by the resulting estimates of two variables: percentage time with the arm elevated 90°. Sixteen measurement strategies involving 1-4 observers repeating their posture ratings 1-4 times were examined for budgets up to €2000. For both posture variables and in both the individual and group scenario, the most cost-efficient strategy at any specific budget was to engage 3-4 observers and/or having observer(s) rate postures multiple times each. Between 17% and 34% less information was produced when using the commonly practiced approach of having one observer rate a number of video recordings one time each. We therefore recommend observational posture assessment to be based on video recordings of work, since this allows for multiple observations; and to allocate monetary resources to repeated observations rather than many video recordings.

  1. Global surface-based cloud observation for ISCCP

    Science.gov (United States)

    1994-01-01

    Visual observations of cloud cover are hindered at night due to inadequate illumination of the clouds. This usually leads to an underestimation of the average cloud cover at night, especially for the amounts of middle and high clouds, in climatologies on surface observations. The diurnal cycles of cloud amounts, if based on all the surface observations, are therefore in error, but they can be obtained more accurately if the nighttime observations are screened to select those made under sufficient moonlight. Ten years of nighttime weather observations from the northern hemisphere in December were classified according to the illuminance of moonlight or twilight on the cloud tops, and a threshold level of illuminance was determined, above which the clouds are apparently detected adequately. This threshold corresponds to light from a full moon at an elevation angle of 6 degrees or from a partial moon at higher elevation, or twilight from the sun less than 9 degrees below the horizon. It permits the use of about 38% of the observations made with the sun below the horizon. The computed diurnal cycles of total cloud cover are altered considerably when this moonlight criterion is imposed. Maximum cloud cover over much of the ocean is now found to be at night or in the morning, whereas computations obtained without benefit of the moonlight criterion, as in our published atlases, showed the time of maximum to be noon or early afternoon in many regions. Cloud cover is greater at night than during the day over the open oceans far from the continents, particularly in summer. However, near noon maxima are still evident in the coastal regions, so that the global annual average oceanic cloud cover is still slightly greater during the day than at night, by 0.3%. Over land, where daytime maxima are still obtained but with reduced amplitude, average cloud cover is 3.3% greater during the daytime. The diurnal cycles of total cloud cover we obtain are compared with those of ISCCP for a

  2. Robust observer-based adaptive fuzzy sliding mode controller

    Science.gov (United States)

    Oveisi, Atta; Nestorović, Tamara

    2016-08-01

    In this paper, a new observer-based adaptive fuzzy integral sliding mode controller is proposed based on the Lyapunov stability theorem. The plant is subjected to a square-integrable disturbance and is assumed to have mismatch uncertainties both in state- and input-matrices. Based on the classical sliding mode controller, the equivalent control effort is obtained to satisfy the sufficient requirement of sliding mode controller and then the control law is modified to guarantee the reachability of the system trajectory to the sliding manifold. In order to relax the norm-bounded constrains on the control law and solve the chattering problem of sliding mode controller, a fuzzy logic inference mechanism is combined with the controller. An adaptive law is then introduced to tune the parameters of the fuzzy system on-line. Finally, for evaluating the controller and the robust performance of the closed-loop system, the proposed regulator is implemented on a real-time mechanical vibrating system.

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

    Science.gov (United States)

    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.

  4. An Observed Voting System Based On Biometric Technique

    Directory of Open Access Journals (Sweden)

    B. Devikiruba

    2015-08-01

    Full Text Available ABSTRACT This article describes a computational framework which can run almost on every computer connected to an IP based network to study biometric techniques. This paper discusses with a system protecting confidential information puts strong security demands on the identification. Biometry provides us with a user-friendly method for this identification and is becoming a competitor for current identification mechanisms. The experimentation section focuses on biometric verification specifically based on fingerprints. This article should be read as a warning to those thinking of using methods of identification without first examine the technical opportunities for compromising mechanisms and the associated legal consequences. The development is based on the java language that easily improves software packages that is useful to test new control techniques.

  5. SCHeMA web-based observation data information system

    Science.gov (United States)

    Novellino, Antonio; Benedetti, Giacomo; D'Angelo, Paolo; Confalonieri, Fabio; Massa, Francesco; Povero, Paolo; Tercier-Waeber, Marie-Louise

    2016-04-01

    It is well recognized that the need of sharing ocean data among non-specialized users is constantly increasing. Initiatives that are built upon international standards will contribute to simplify data processing and dissemination, improve user-accessibility also through web browsers, facilitate the sharing of information across the integrated network of ocean observing systems; and ultimately provide a better understanding of the ocean functioning. The SCHeMA (Integrated in Situ Chemical MApping probe) Project is developing an open and modular sensing solution for autonomous in situ high resolution mapping of a wide range of anthropogenic and natural chemical compounds coupled to master bio-physicochemical parameters (www.schema-ocean.eu). The SCHeMA web system is designed to ensure user-friendly data discovery, access and download as well as interoperability with other projects through a dedicated interface that implements the Global Earth Observation System of Systems - Common Infrastructure (GCI) recommendations and the international Open Geospatial Consortium - Sensor Web Enablement (OGC-SWE) standards. This approach will insure data accessibility in compliance with major European Directives and recommendations. Being modular, the system allows the plug-and-play of commercially available probes as well as new sensor probess under development within the project. The access to the network of monitoring probes is provided via a web-based system interface that, being implemented as a SOS (Sensor Observation Service), is providing standard interoperability and access tosensor observations systems through O&M standard - as well as sensor descriptions - encoded in Sensor Model Language (SensorML). The use of common vocabularies in all metadatabases and data formats, to describe data in an already harmonized and common standard is a prerequisite towards consistency and interoperability. Therefore, the SCHeMA SOS has adopted the SeaVox common vocabularies populated by

  6. Observational Selection Effects with Ground-based Gravitational Wave Detectors

    CERN Document Server

    Chen, Hsin-Yu; Vitale, Salvatore; Holz, Daniel E; Katsavounidis, Erik

    2016-01-01

    Ground-based interferometers are not perfectly all-sky instruments, and it is important to account for their behavior when considering the distribution of detected events. In particular, the LIGO detectors are most sensitive to sources above North America and the Indian Ocean and, as the Earth rotates, the sensitive regions are swept across the sky. However, because the detectors do not acquire data uniformly over time, there is a net bias on detectable sources' right ascensions. Both LIGO detectors preferentially collect data during their local night; it is more than twice as likely to be local midnight than noon when both detectors are operating. We discuss these selection effects and how they impact LIGO's observations and electromagnetic follow-up. Beyond galactic foregrounds associated with seasonal variations, we find that equatorial observatories can access over $80\\%$ of the localization probability, while mid-latitudes will access closer to $70\\%$. Facilities located near the two LIGO sites can obser...

  7. "Sniffing" Jupiter's moon Europa through ground-based IR observations

    Science.gov (United States)

    Paganini, Lucas; Mumma, Michael J.; Hurford, Terry; Roth, Lorenz; Villanueva, Geronimo Luis

    2016-10-01

    The ability to sample possible plumes from the subsurface ocean in Europa represents a major step in our search for extraterrestrial life. If plumes exist, sampling the effluent material would provide insights into their chemistry and relevant information about the prospect that life could exist, or now exists, within the ocean. Most of the difficulties in detecting plumes come from the less frequent observational coverage of Europa, which contrasts strongly with the frequent Cassini flybys of Enceladus (Spencer & Nimmo 2013). Recent observations have been taken with HST/STIS in 2014/2015, but results have shown no evident confirmation of the 2012 plume detection (Roth et al. 2014, 2015). Future in situ observations (Europa Mission) will provide definitive insights, but not before the spacecraft's arrival in ~2025, thus an interim approach is needed to inform such space mission planning and to complement existing observations at other wavelengths.In 2015, we initiated a strong campaign to build a comprehensive survey of possible plumes on Europa through high-resolution IR spectroscopy with Keck/NIRSPEC. We were awarded 10 nights out of 15 total nights available for Key Strategic Mission Support projects for the 2016A, 2016B, 2017A, and 2017B semesters under NASA time with the Keck Observatory. In 2016A, we observed Europa during 10 half-nights and will continue to do so for another 10 half-nights in 2017A. We target a serendipitous search of gaseous activity from Europa to confirm and constrain the chemical composition of possible Europan plumes that can aid the investigation of physical processes underlying (or on) its surface. Ultimately, we seek to: (1) provide information that can inform planning for NASA's Europa mission, (2) further our current understanding of Europa's gas environment, and (3) complement studies that are currently underway with other facilities (like the Hubble Space Telescope). In this presentation, we will discuss preliminary results

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

    Science.gov (United States)

    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.

  9. Observer-based and Regression Model-based Detection of Emerging Faults in Coal Mills

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Lin, Bao; Jørgensen, Sten Bay

    2006-01-01

    In order to improve the reliability of power plants it is important to detect fault as fast as possible. Doing this it is interesting to find the most efficient method. Since modeling of large scale systems is time consuming it is interesting to compare a model-based method with data driven ones....... In this paper three different fault detection approaches are compared using a example of a coal mill, where a fault emerges. The compared methods are based on: an optimal unknown input observer, static and dynamic regression model-based detections. The conclusion on the comparison is that observer-based scheme...

  10. Observer-Based Magnetic Bearing Controller Developed for Aerospace Flywheels

    Science.gov (United States)

    Le, Dzu K.; Provenza, Andrew J.

    2002-01-01

    A prototype of a versatile, observer-based magnetic bearing controller for aerospace flywheels was successfully developed and demonstrated on a magnetic bearing test rig (see the photograph) and an actual flywheel module. The objective of this development included a fast, yet low risk, control development process, and a robust, high-performance controller for a large variety of flywheels. This required a good system model, an efficient development procedure, and a model-based controller that addressed the key problems associated with flywheel and bearing imbalance, sensor error, and vibration. The model used in this control development and tuning procedure included the flexible rotor dynamics and motor-induced vibrations. Such a model was essential for low-risk scheduling of speed-dependent control parameters and for reliable evaluation of novel control strategies. The successfully tested control prototype utilized an extended Kalman filter to estimate the true rotor principal-axis motion from the raw sensor position feedback. For control refinement, the extended Kalman filter also estimated and eliminated the combined effects of mass-imbalance and sensor runouts from the input data. A key advantage of the design based on the extended Kalman filter is its ability to accurately estimate both the rotor's principal-axis position and gyroscopic rates with the least amount of phase lag. This is important for control parameter scheduling to dampen the gyroscopic motions. Because of large uncertainties in the magnetic bearing and imbalance characteristics, this state-estimation scheme alone is insufficient for containing the rotor motion within the desired 1-mil excursion radius. A nonlinear gain adjustment based on an estimation of the principal-axis orbit size was needed to provide a coarse (nonoptimal), but robust, control of the orbit growth. Control current minimization was achieved with a (steepest gradient) search of synchronous errors in the principal

  11. Acceptability of the reusable SurePal™ self-injection device for Omnitrope® among pediatric patients: results from a questionnaire-based, cross-sectional, multicenter observational study

    Directory of Open Access Journals (Sweden)

    Partsch CJ

    2015-09-01

    Full Text Available Carl-Joachim Partsch,1 Dirk Schnabel,2 Sarah Ehtisham,3 Helen C Johnstone,4 Markus Zabransky,5 Wieland Kiess61Endokrinologikum Hamburg, Hamburg, 2Division of Endocrinology and Diabetology, Otto-Heubner-Center for Pediatric and Adolescent Medicine, Charité University, Berlin, Germany; 3Central Manchester University Hospitals NHS Foundation Trust, Manchester, 4The Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle, UK; 5Sandoz International GmbH, Holzkirchen, 6Department of Women and Child Health, Hospital for Children and Adolescents, University Hospitals, University of Leipzig, Leipzig, GermanyBackground: SurePal™ is a reusable self-injection system that has been developed to support daily administration of Omnitrope® (Sandoz, Kundl, Austria. A questionnaire-based cross-sectional survey was conducted to evaluate acceptability of, and preference for, SurePal™ in pediatric patients who were prescribed treatment with Omnitrope® within routine clinical care.Methods: This multicenter, observational study was incorporated into the ongoing non-interventional PATRO (PAtients TReated with Omnitrope® Children study. Patients (or caregivers were provided with a questionnaire that included five main topics; attractiveness of the device, training received, using SurePal™, the low drug wastage system, and experience versus other devices used previously (where applicable. Questions were scored on a 5-point scale, with -2 being the worst possible outcome (eg, very hard/very poor and 2 being the best possible outcome (eg, very easy/excellent.Results: A total of 186 patients were included in this study (Germany, n=154; UK, n=32. The attractiveness of SurePal™ was rated as excellent/good by 87.1% of patients. Overall, 86.5% of patients found that using their SurePal™ was very easy/easy. Almost all patients (96.2% found that preparing their SurePal™ for injection was very easy/easy, and 89.2% found that injecting with SurePal™ was very

  12. Strengthening the Reporting of Observational Studies in Epidemiology (STROBE)

    DEFF Research Database (Denmark)

    Vandenbroucke, Jan P; von Elm, Erik; Altman, Douglas G;

    2014-01-01

    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...

  13. Grid-based platform for training in Earth Observation

    Science.gov (United States)

    Petcu, Dana; Zaharie, Daniela; Panica, Silviu; Frincu, Marc; Neagul, Marian; Gorgan, Dorian; Stefanut, Teodor

    2010-05-01

    GiSHEO platform [1] providing on-demand services for training and high education in Earth Observation is developed, in the frame of an ESA funded project through its PECS programme, to respond to the needs of powerful education resources in remote sensing field. It intends to be a Grid-based platform of which potential for experimentation and extensibility are the key benefits compared with a desktop software solution. Near-real time applications requiring simultaneous multiple short-time-response data-intensive tasks, as in the case of a short time training event, are the ones that are proved to be ideal for this platform. The platform is based on Globus Toolkit 4 facilities for security and process management, and on the clusters of four academic institutions involved in the project. The authorization uses a VOMS service. The main public services are the followings: the EO processing services (represented through special WSRF-type services); the workflow service exposing a particular workflow engine; the data indexing and discovery service for accessing the data management mechanisms; the processing services, a collection allowing easy access to the processing platform. The WSRF-type services for basic satellite image processing are reusing free image processing tools, OpenCV and GDAL. New algorithms and workflows were develop to tackle with challenging problems like detecting the underground remains of old fortifications, walls or houses. More details can be found in [2]. Composed services can be specified through workflows and are easy to be deployed. The workflow engine, OSyRIS (Orchestration System using a Rule based Inference Solution), is based on DROOLS, and a new rule-based workflow language, SILK (SImple Language for worKflow), has been built. Workflow creation in SILK can be done with or without a visual designing tools. The basics of SILK are the tasks and relations (rules) between them. It is similar with the SCUFL language, but not relying on XML in

  14. Data base management study

    Science.gov (United States)

    1976-01-01

    Data base management techniques and applicable equipment are described. Recommendations which will assist potential NASA data users in selecting and using appropriate data base management tools and techniques are presented. Classes of currently available data processing equipment ranging from basic terminals to large minicomputer systems were surveyed as they apply to the needs of potential SEASAT data users. Cost and capabilities projections for this equipment through 1985 were presented. A test of a typical data base management system was described, as well as the results of this test and recommendations to assist potential users in determining when such a system is appropriate for their needs. The representative system tested was UNIVAC's DMS 1100.

  15. Simulation study for measurement of horizontal wind profiles in the polar stratosphere and mesosphere using ground-based observations of ozone and carbon monoxide lines in the 230-250 GHz region

    Science.gov (United States)

    Newnham, David A.; Ford, George P.; Moffat-Griffin, Tracy; Pumphrey, Hugh C.

    2016-07-01

    Meteorological and atmospheric models are being extended up to 80 km altitude but there are very few observing techniques that can measure stratospheric-mesospheric winds at altitudes between 20 and 80 km to verify model datasets. Here we demonstrate the feasibility of horizontal wind profile measurements using ground-based passive millimetre-wave spectroradiometric observations of ozone lines centred at 231.28, 249.79, and 249.96 GHz. Vertical profiles of horizontal winds are retrieved from forward and inverse modelling simulations of the line-of-sight Doppler-shifted atmospheric emission lines above Halley station (75°37' S, 26°14' W), Antarctica. For a radiometer with a system temperature of 1400 K and 30 kHz spectral resolution observing the ozone 231.28 GHz line we estimate that 12 h zonal and meridional wind profiles could be determined over the altitude range 25-74 km in winter, and 28-66 km in summer. Height-dependent measurement uncertainties are in the range 3-8 m s-1 and vertical resolution ˜ 8-16 km. Under optimum observing conditions at Halley a temporal resolution of 1.5 h for measuring either zonal or meridional winds is possible, reducing to 0.5 h for a radiometer with a 700 K system temperature. Combining observations of the 231.28 GHz ozone line and the 230.54 GHz carbon monoxide line gives additional altitude coverage at 85 ± 12 km. The effects of clear-sky seasonal mean winter/summer conditions, zenith angle of the received atmospheric emission, and spectrometer frequency resolution on the altitude coverage, measurement uncertainty, and height and time resolution of the retrieved wind profiles have been determined.

  16. Factors affecting purse seine catches: an observer-based analysis

    Directory of Open Access Journals (Sweden)

    E.V. TSITSIKA

    2012-12-01

    Full Text Available A total of 72 fi shing trips were carried out by fi shery scientists onboard a purse seiner in the Pagasitikos Gulf (Greece in an attempt to identify factors affecting total and individual species’ catches. As trawling is completely banned in the study area, purse seining is the main fi shing method. It was found that month, water depth and fi shing area affected total and Trachurus spp. catches of the purse seine fi shery, with month and water depth alone explaining 77.8% and 6.4% respectively of the total variation of the data. Signifi cant interactions observed indicate that the fl uctuations in total catches differed by month and fi shing area as well as fi shing area and water depth. Fishing area and water depth interaction were found to affect Trachurus spp. catches signifi cantly. Results also suggested that generalized linear modelling of the purse seine catches can be used to obtain representative abundance indices by reducing the observed variability. Fishery scientists’ onboard observations alongside fi sh market recordings during the same period confi rmed that each fi sher has developed an individual decision-making fi shing process. Fisher’s trip choice behaviour was found to be modulated by several factors, such as distance of fi shing grounds from the port, market demands (both in terms of species and market prices, weather conditions, alternative fi shing strategies, previously gathered information, economic pressure and personal skills. These fi ndings are discussed in the light of the need to incorporate additional quantitative information to stock abundance estimates if improved fi sheries management scenarios are to be advanced.

  17. Giant cell arteritis: a multicenter observational study in Brazil

    Directory of Open Access Journals (Sweden)

    Alexandre Wagner Silva de Souza

    2013-01-01

    Full Text Available OBJECTIVE: To describe demographic features, disease manifestations and therapy in patients with giant cell arteritis from referral centers in Brazil. METHODS: A retrospective cohort study was performed on 45 giant cell arteritis patients from three university hospitals in Brazil. Diagnoses were based on the American College of Rheumatology classification criteria for giant cell arteritis or temporal artery biopsy findings. RESULTS: Most patients were Caucasian, and females were slightly more predominant. The frequencies of disease manifestations were as follows: temporal headache in 82.2%, neuro-ophthalmologic manifestations in 68.9%, jaw claudication in 48.9%, systemic symptoms in 44.4%, polymyalgia rheumatica in 35.6% and extra-cranial vessel involvement in 17.8% of cases. Aortic aneurysms were observed in 6.6% of patients. A comparison between patients with biopsy-proven giant cell arteritis and those without temporal artery biopsies did not yield significant differences in disease manifestations. All patients were treated with oral prednisone, and intravenous methylprednisolone was administered to nearly half of the patients. Methotrexate was the most commonly used immunosuppressive agent, and low-dose aspirin was prescribed to the majority of patients. Relapses occurred in 28.9% of patients, and aspirin had a protective effect against relapses. Females had higher prevalences of polymyalgia rheumatica, systemic manifestations and jaw claudication, while permanent visual loss was more prevalent in men. CONCLUSIONS: Most of the clinical features of Brazilian giant cell arteritis patients were similar to those found in other studies, except for the high prevalence of neuro-ophthalmic manifestations and permanent blindness in the Brazilian patients. Aspirin had a protective effect on relapses.

  18. A new permutation-based method for assessing agreement between two observers making replicated quantitative readings.

    Science.gov (United States)

    Pan, Yi; Haber, Michael; Gao, Jingjing; Barnhart, Huiman X

    2012-09-10

    The coefficient of individual equivalence is a permutation-based measure of agreement between two observers making replicated readings on each subject. It compares the observed disagreement between the observers to the expected disagreement under individual equivalence. Individual equivalence of observers requires that for every study subject, the conditional distributions of the readings of the observers given the subject's characteristics are identical. Therefore, under individual equivalence it does not matter which observer is making a particular reading on a given subject. We introduce both nonparametric and parametric methods to estimate the coefficient as well as its standard error. We compare the new coefficient with the coefficient of individual agreement and with the concordance correlation coefficient. We also evaluate the performance of the estimates of the new coefficient via simulations and illustrate this new approach using data from a study comparing two noninvasive techniques for measuring carotid stenosis to an invasive gold standard.

  19. Ground-Based Observing Campaign of Briz-M Debris

    Science.gov (United States)

    Lederer, S. M.; Buckalew, B.; Frith, J.; Cowardin, H. M.; Hickson, P.; Matney, M.; Anz-Meador, P.

    2017-01-01

    In 2015, NASA's Orbital Debris Program Office (ODPO) completed the installation of the Meter Class Autonomous Telescope (MCAT) on Ascension Island. MCAT is a 1.3m optical telescope designed with a fast tracking capability for observing orbital debris at all orbital regimes (Low-Erath orbits to Geosyncronous (GEO) orbits) from a low latitude site. This new asset is dedicated year-round for debris observations, and its location fills a geographical gap in the Ground-based Electro Optical Space Surveillance (GEODSS) network. A commercial off the shelf (COTS) research grade 0.4m telescope (named the Benbrook telescope) will also be installed on Ascension at the end of 2016. This smaller version is controlled by the same master software, designed by Euclid Research, and can be tasked to work independently or in concert with MCAT. Like MCAT, it has a the same suite of filters, a similar field of view, and a fast-tracking Astelco mount, and is also capable of tracking debris at all orbital regimes. These assets are well suited for targeted campagins or surveys of debris. Since 2013, NASA's ODPO has also had extensive access to the 3.8m infrared UKIRT telescope, located on Mauna Kea. At nearly 14,000-ft, this site affords excellent conditions for collecting both photometery and spectroscopy at near-IR (0.9 - 2.5 micrometers SWIR) and thermal-IR (8 - 25 micrometers; LWIR) regimes, ideal for investigating material properties as well as thermal characteristics and sizes of debris. For the purposes of understanding orbital debris, taking data in both survey mode as well as targeting individual objects for more in-depth characterizations are desired. With the recent break-ups of Briz-M rocket bodies, we have collected a suite of data in the optical, near-infrared, and mid-infrared of in-tact objects as well as those classified as debris. A break-up at GEO of a Briz-M rocket occurred in January, 2016, well timed for the first remote observing survey-campaign with MCAT. Access to

  20. CEOS Contributions to Informing Energy Management and Policy Decision Making Using Space-Based Earth Observations

    Science.gov (United States)

    Eckman, Richard S.

    2009-01-01

    Earth observations are playing an increasingly significant role in informing decision making in the energy sector. In renewable energy applications, space-based observations now routinely augment sparse ground-based observations used as input for renewable energy resource assessment applications. As one of the nine Group on Earth Observations (GEO) societal benefit areas, the enhancement of management and policy decision making in the energy sector is receiving attention in activities conducted by the Committee on Earth Observation Satellites (CEOS). CEOS has become the "space arm" for the implementation of the Global Earth Observation System of Systems (GEOSS) vision. It is directly supporting the space-based, near-term tasks articulated in the GEO three-year work plan. This paper describes a coordinated program of demonstration projects conducted by CEOS member agencies and partners to utilize Earth observations to enhance energy management end-user decision support systems. I discuss the importance of engagement with stakeholders and understanding their decision support needs in successfully increasing the uptake of Earth observation products for societal benefit. Several case studies are presented, demonstrating the importance of providing data sets in formats and units familiar and immediately usable by decision makers. These projects show the utility of Earth observations to enhance renewable energy resource assessment in the developing world, forecast space-weather impacts on the power grid, and improve energy efficiency in the built environment.

  1. Study of white-light flares observed by Hinode

    Institute of Scientific and Technical Information of China (English)

    Hai-Min Wang

    2009-01-01

    White-light flares are considered to be the most energetic flaring events that are observable in the optical broad-band continuum of the solar spectrum. They have not been commonly observed. Observations of white-light flares with sub-arcsecond resolution have been very rare. The continuous high resolution observations of Hinode provide a unique opportunity to systematically study the white-light flares with a spatial resolution around 0.2 arcsec. We surveyed all the flares above GOES magnitude C5.0 since the launch of Hinode in 2006 October. 13 of these kinds of flares were covered by the Hinode G-band observations. We analyzed the peak contrasts and equivalent areas (calculated via integrated excess emission contrast) of these flares as a function of the GOES X-ray flux, and found that the cut-off visibility is likely around M1 flares under the observing limit of Hinode. Many other observational and physical factors should affect the visibility of white-light flares; as the observing conditions are improved, smaller flares are likely to have detectable white-light emissions. We are cautious that this limiting visibility is an overestimate, because G-band observations contain emissions from the upper atmosphere.Among the 13 events analyzed, only the M8.7 flare of 2007 June 4 had near-simultaneous observations in both the G-band and the blue continuum. The blue continuum had a peak contrast of 94% vs. 175% in G-band for this event. The equivalent area in the blue continuum is an order of magnitude lower than that in the G-band. Very recently, Jess et al.studied a C2.0 flare with a peak contrast of 300% in the blue continuum. Compared to the events presented in this letter, that event is probably an unusual white-light flare: a very small kernel with a large contrast that can be detected in high resolution observations.

  2. Distributed estimation based on observations prediction in wireless sensor networks

    KAUST Repository

    Bouchoucha, Taha

    2015-03-19

    We consider wireless sensor networks (WSNs) used for distributed estimation of unknown parameters. Due to the limited bandwidth, sensor nodes quantize their noisy observations before transmission to a fusion center (FC) for the estimation process. In this letter, the correlation between observations is exploited to reduce the mean-square error (MSE) of the distributed estimation. Specifically, sensor nodes generate local predictions of their observations and then transmit the quantized prediction errors (innovations) to the FC rather than the quantized observations. The analytic and numerical results show that transmitting the innovations rather than the observations mitigates the effect of quantization noise and hence reduces the MSE. © 2015 IEEE.

  3. Studies on male genitalia of sarcophagidae (Diptera based on scanning electron microscope observations Estudos sobre a genitália masculina de Sarcophagidae (Diptera baseados em observações de microscópio de varredura

    Directory of Open Access Journals (Sweden)

    Antônio Cesar Rios Leite

    1989-06-01

    Full Text Available Male genitalia of Oxyvinia exicisa (Lopes, Oxysarcodexia thomax (Walker, O. fluminensis Lopes, Sarcodexia lambens (Wiedemann, Peckia chrysostoma (Wiedemann and Liopygia ruficornis (Fabricius were studied based on scanning electron microscope photography. Some important details were evidentiated with this method.As genitálias dos machos de Oxyvinia excisa (Lopes, Oxysarcodexia tornax (Walker, O. fluminensis Lopes, sarcodexia lambens (Wiedemann, Peckia chrysostoma (Wiedemann e Liopygia ruficornis (Fabricius foram estudadas com base em fotografias de microscópio de varredura. Alguns detalhes importantes foram evidenciados por este método.

  4. SABRE observations of Pi2 pulsations: case studies

    Science.gov (United States)

    Bradshaw, E. G.; Lester, M.

    1997-01-01

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

  5. Scientific and Ethical Approaches for Observational Exposure Studies

    Science.gov (United States)

    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...

  6. Serum YKL-40 and gestational diabetes - an observational cohort study

    DEFF Research Database (Denmark)

    Gybel-Brask, Dorte; Johansen, Julia S; Christiansen, Ib J;

    2016-01-01

    To examine serum YKL-40 in women developing gestational diabetes mellitus (GDM). In the present large observational cohort study of 1179 pregnant women, we determined serum YKL-40 four times during pregnancy (at gestational age 12, 20, 25, and 32 weeks). Pregnancy outcome was obtained from medical...

  7. Observational studies of transiting extrasolar planets (invited review)

    CERN Document Server

    Southworth, John

    2014-01-01

    The study of transiting extrasolar planets is only 15 years old, but has matured into a rich area of research. I review the observational aspects of this work, concentrating on the discovery of transits, the characterisation of planets from photometry and spectroscopy, the Homogeneous Studies project, starspots, orbital obliquities, and the atmospheric properties of the known planets. I begin with historical context and conclude with a glance to a future of TESS, CHEOPS, Gaia and PLATO.

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

    Science.gov (United States)

    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.

  9. Observation-Based Dissipation and Input Terms for Spectral Wave Models, with End-User Testing

    Science.gov (United States)

    2014-09-30

    Zieger, S. “Wave climate in the marginal ice zones of Arctic Seas, observations and modelling”. ONR Sea State DRU project. Studies wave climate in the...Rinke, and H. Matthes, 2014: Projected changes of wind-wave activity in the Arctic Ocean. Proceedings of the 22nd IAHR International Symposium on Ice ...objectives are to use new observation-based source terms for the wind input, wave-breaking (whitecapping) dissipation and swell decay in the third

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

    Science.gov (United States)

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

    2016-01-01

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

  11. Detailed Study of the Internal Structure of a Red-giant Star Observed with Kepler

    DEFF Research Database (Denmark)

    Di Mauro, M. P.; Ventura, R.; Cardini, D.;

    2012-01-01

    We study the internal structure and evolutionary state of KIC 4351319, a red-giant star observed with the Kepler satellite. The use of 25 individual oscillation frequencies, together with the accurate atmospheric data provided by ground-based spectroscopic observations, allowed us to estimate the...

  12. Observations

    DEFF Research Database (Denmark)

    Rossiter, John R.; Percy, Larry

    2013-01-01

    as requiring a new model of how advertising communicates and persuades, which, as the authors' textbooks explain, is sheer nonsense and contrary to the goal of integrated marketing. We provide in this article a translation of practitioners' jargon into more scientifically acceptable terminology as well...... product or service or to achieve a higher price that consumers are willing to pay than would obtain in the absence of advertising. What has changed in recent years is the notable worsening of the academic-practitioner divide, which has seen academic advertising researchers pursuing increasingly...... unrealistic laboratory studies, textbook writers continuing to ignore practitioners' research appearing in trade publications and practitioner-oriented journals, and practitioners peeling off into high-sounding but meaningless jargon. also evident is the tendency to regard the new electronic media...

  13. Observational Studies on Evaluating the Safety and Adverse Effects of Traditional Chinese Medicine

    OpenAIRE

    Jung-Nein Lai; Jin-Ling Tang; Jung-Der Wang

    2013-01-01

    Background. This study aims to share our experiences when carrying out observational studies of traditional Chinese medicine (TCM). Methods. We have proactively monitored the safety profiles of Duhuo Jisheng Tang (DJT), Suan Zao Ren Tang (SZRT), and TMN-1. A list of adverse events (AEs), complete blood counts, and liver and kidney function tests were obtained from the participants during their scheduled hospital visits. Retrospective observational studies were conducted based on the reimburse...

  14. CHATURBEEJA IN PRIMARY DYSMENORRHOEA (KASHTARTAVA: AN OBSERVATIONAL STUDY

    Directory of Open Access Journals (Sweden)

    Dhiman Kamini

    2012-06-01

    Full Text Available In folk medicines, Chaturbeeja(combination of seeds of four plants i.e Trigonella Foenum-graecum, Lepidium sativum , Nigella sativa, Trachyspermum ammi in equal quantity has been traditionally used for variety of applications including treatment of Dysmenorrhoea, the most common gynaecological symptom reported by women. To promote the proper use of such medicines and to determine their potential as sources for new drugs, it is essential to study medicinal plants, which have folklore reputation in a more intensified way. A Single blind, prospective observational clinical study was conducted to evaluate the efficacy of Chaturbeeja powder in Primary Dysmenorrhoea (Kashtartava. 25 patients were administered Chaturbeeja powder in a single dose of 3g with hot water at night, 7 days before starting of menstruation till 3rd day of the menstruation cycle. After assessing the results it was observed that12 patients were markedly improved, 8 moderately improved and 5 were improved.

  15. Cauchy problem for Laplace equation: An observer based approach

    KAUST Repository

    Majeed, Muhammad Usman

    2013-10-01

    A method to solve Cauchy Problem for Laplace equation using state observers is proposed. It is known that this problem is ill-posed. The domain under consideration is simple lipschitz in 2 with a hole. The idea is to recover the solution over whole domain from the observations on outer boundary. Proposed approach adapts one of the space variables as a time variable. The observer developed to solve Cauchy problem for the Laplace\\'s equation is compuationally robust and accurate. © 2013 IEEE.

  16. Study of the upper atmosphere observation by artificial ion beam

    OpenAIRE

    Sugimoto, Sachiko; Kuninaka, Hitoshi; TOKI, Kyoichiro; Arakawa, Yoshihiro; 杉本 幸子; 國中 均; 都木 恭一郎; 荒川 義博

    2005-01-01

    The observing method that uses ENA (Energetic Neutral Atoms), produced by ion beam injected from an ion thruster, is studied and researched in order to estimate the density of neutral particles in the upper atmosphere. The ion beam experiences charge exchange collision (CEX) with neighboring neutral particles to transform into ENAs. The ENA preserves the information about the particles concerned with those collisions. A new method of estimating the density and the composition of the neutral p...

  17. Observed Orbit Effects during Long Range Beam-Beam Studies

    CERN Document Server

    Alemany, R; Buffat, X; Calaga, R; Fitterer, M; Giachino, R; Hemelsoet, GH; Herr, W; Papotti, G; Pieloni, T; Poyer, M; Schaumann, M; Trad, G; Wollmann, D

    2012-01-01

    Possible limitations due to long range beam-beam effects at the LHC have been studied and are presented in this note. With a larger number of bunches and collisions in all interaction points, the crossing angles were reduced to enhance long range beam-beam effects. The analysis of the effects on the dynamic aperture and losses are documented in [1]. This note concentrates on the bunch-by-bunch orbit effects observed during the experiment.

  18. Observational study of maternal anthropometry and fetal insulin

    OpenAIRE

    Soltani-K, H; Bruce, C; Fraser, R

    1999-01-01

    AIMS—To examine the relation between maternal body fat and fetal metabolism.
METHODS—In this observational study, cord blood samples were collected from 60 infants of healthy women for the measurement of insulin and C peptide concentrations. Maternal weight, height, body mass index (BMI) and body composition (skinfold thickness measurements and bioelectrical impedance) were assessed at 13-15 weeks of gestation. Twenty five of the volunteers agreed to have a 75 g oral gluc...

  19. Study of phyllosilicates and carbonates from the Capri Chasma region of Valles Marineris on Mars based on Mars Reconnaissance Orbiter-Compact Reconnaissance Imaging Spectrometer for Mars (MRO-CRISM) observations

    Science.gov (United States)

    Jain, Nirmala; Chauhan, Prakash

    2015-04-01

    Spectral reflectance data from the MRO-CRISM (Mars Reconnaissance Orbiter-Compact Reconnaissance Imaging Spectrometer for Mars) of Capri Chasma, a large canyon within Valles Marineris on Mars, have been studied. Results of this analysis reveal the presence of minerals, such as, phyllosilicates (illite, smectite (montmorillonite)) and carbonates (ankerite and manganocalcite). These minerals hint of the aqueous history of Noachian time on Mars. Phyllosilicates are products of chemical weathering of igneous rocks, whereas carbonates could have formed from local aqueous alteration of olivine and other igneous minerals. Four different locations within the Capri Chasma region were studied for spectral reflectance based mineral detection. The study area also shows the spectral signatures of iron-bearing minerals, e.g. olivine with carbonate, indicating partial weathering of parent rocks primarily rich in ferrous mineral. The present study shows that the minerals of Capri Chasma are characterized by the presence of prominent spectral absorption features at 2.31 μm, 2.33 μm, 2.22 μm, 2.48 μm and 2.52 μm wavelength regions, indicating the existence of hydrous minerals, i.e., carbonates and phyllosilicates. The occurrence of carbonates and phyllosilicates in the study area suggests the presence of alkaline environment during the period of their formation. Results of the study are important to understand the formation processes of these mineral assemblages on Mars, which may help in understanding the evolutionary history of the planet.

  20. Event-based internet biosurveillance: relation to epidemiological observation

    Directory of Open Access Journals (Sweden)

    Nelson Noele P

    2012-06-01

    Full Text Available Abstract Background The World Health Organization (WHO collects and publishes surveillance data and statistics for select diseases, but traditional methods of gathering such data are time and labor intensive. Event-based biosurveillance, which utilizes a variety of Internet sources, complements traditional surveillance. In this study we assess the reliability of Internet biosurveillance and evaluate disease-specific alert criteria against epidemiological data. Methods We reviewed and compared WHO epidemiological data and Argus biosurveillance system data for pandemic (H1N1 2009 (April 2009 – January 2010 from 8 regions and 122 countries to: identify reliable alert criteria among 15 Argus-defined categories; determine the degree of data correlation for disease progression; and assess timeliness of Internet information. Results Argus generated a total of 1,580 unique alerts; 5 alert categories generated statistically significant (p  Conclusion Confirmed pandemic (H1N1 2009 cases collected by Argus and WHO methods returned consistent results and confirmed the reliability and timeliness of Internet information. Disease-specific alert criteria provide situational awareness and may serve as proxy indicators to event progression and escalation in lieu of traditional surveillance data; alerts may identify early-warning indicators to another pandemic, preparing the public health community for disease events.

  1. Handover patterns: an observational study of critical care physicians

    Directory of Open Access Journals (Sweden)

    Ilan Roy

    2012-01-01

    Full Text Available Abstract Background Handover (or 'handoff' is the exchange of information between health professionals that accompanies the transfer of patient care. This process can result in adverse events. Handover 'best practices', with emphasis on standardization, have been widely promoted. However, these recommendations are based mostly on expert opinion and research on medical trainees. By examining handover communication of experienced physicians, we aim to inform future research, education and quality improvement. Thus, our objective is to describe handover communication patterns used by attending critical care physicians in an academic centre and to compare them with currently popular, standardized schemes for handover communication. Methods Prospective, observational study using video recording in an academic intensive care unit in Ontario, Canada. Forty individual patient handovers were randomly selected out of 10 end-of-week handover sessions of attending physicians. Two coders independently reviewed handover transcripts documenting elements of three communication schemes: SBAR (Situation, Background, Assessment, Recommendations; SOAP (Subjective, Objective, Assessment, Plan; and a standard medical admission note. Frequency and extent of questions asked by incoming physicians were measured as well. Analysis consisted of descriptive statistics. Results Mean (± standard deviation duration of patient-specific handovers was 2 min 58 sec (± 57 sec. The majority of handovers' content consisted of recent and current patient status. The remainder included physicians' interpretations and advice. Questions posed by the incoming physicians accounted for 5.8% (± 3.9% of the handovers' content. Elements of all three standardized communication schemes appeared repeatedly throughout the handover dialogs with no consistent pattern. For example, blocks of SOAP's Assessment appeared 5.2 (± 3.0 times in patient handovers; they followed Objective blocks in only 45

  2. Observational cohort study of HIV-infected African children.

    NARCIS (Netherlands)

    Laufer, M.K.; Oosterhout, J.J. van; Perez, M.A.; Kanyanganlika, J.; Taylor, T.E.; Plowe, C.V.; Graham, S.M.

    2006-01-01

    BACKGROUND: Most information about children living with HIV is based on follow up from children identified through mother-to-child transmission studies. Children identified through voluntary counseling and testing (VCT) represent a unique cohort that has not been previously described in the literatu

  3. Ground-based observations of Kepler asteroseismic targets

    DEFF Research Database (Denmark)

    Uyttterhoeven , K.; Karoff, Christoffer

    2010-01-01

    We present the ground-based activities within the different working groups of the Kepler Asteroseismic Science Consortium (KASC). The activities aim at the systematic characterization of the 5000+ KASC targets, and at the collection of ground-based follow-up time-series data of selected promising...

  4. 基于星敏感器双矢量观测信息的卫星姿态确定算法研究%Study of Satellite Attitude Determination Algorithm Based on Two-vector Observation of Star Sensor

    Institute of Scientific and Technical Information of China (English)

    王志刚; 邓逸凡

    2011-01-01

    Presented and probed into algorithms from two vector observation based on star sensor, QUEST algorithm and algorithms using Extended Kalman Filter ( EKF) with gyros measurements, were derived respectively. And higher accuracy of filtering algorithm using star sensor and gyros comparing with the QUEST algorithms through simulation test is validated.%针对三轴稳定卫星,研究基于星敏感器双矢量观测信息的卫星高精度姿态确定算法.建立了姿态运动学模型、敏感器测量模型、QUEST算法模型和扩展卡尔曼滤波(EKF)模型.对比分析了QUEST算法以及星敏感器与陀螺组合的扩展卡尔曼滤波(EKF)算法的定姿精度.通过数学仿真,表明基于星敏感器和陀螺的扩展卡尔曼滤波组合姿态确定算法具有更高的定姿精度.

  5. Ground-Based Observations of Unusual Atmospheric Light Emissions

    Institute of Scientific and Technical Information of China (English)

    杨静; 陆高鹏; 杜艰; 潘蔚琳

    2014-01-01

    Unusual atmospheric light emissions were observed from a station located in Shandong Province of East China. The main morphology of these events includes a bright glowing spot, which differs distinctly from any type of transient luminous events (TLEs) well recognized in literature, such as sprites, halos, elves, gigantic jets, blue jets, and blue starters. A comparison between the observations of four such light emission events and the data from lightning detection networks reveals no correlation between these events and the intense lightning activity in the adjacent area. The events reported in this paper may imply the existence of a new phenomenon with a mechanism that remains to be investigated with further observation and complementary lightning measurement.

  6. Observations of the Geometry of Horizon-Based Optical Navigation

    Science.gov (United States)

    Christian, John; Robinson, Shane

    2016-01-01

    NASA's Orion Project has sparked a renewed interest in horizon-based optical navigation(OPNAV) techniques for spacecraft in the Earth-Moon system. Some approaches have begun to explore the geometry of horizon-based OPNAV and exploit the fact that it is a conic section problem. Therefore, the present paper focuses more deeply on understanding and leveraging the various geometric interpretations of horizon-based OPNAV. These results provide valuable insight into the fundamental workings of OPNAV solution methods, their convergence properties, and associated estimate covariance. Most importantly, the geometry and transformations uncovered in this paper lead to a simple and non-iterative solution to the generic horizon-based OPNAV problem. This represents a significant theoretical advancement over existing methods. Thus, we find that a clear understanding of geometric relationships is central to the prudent design, use, and operation of horizon-based OPNAV techniques.

  7. Observer-based Fault Detection and Isolation for Nonlinear Systems

    DEFF Research Database (Denmark)

    Lootsma, T.F.

    . Then the geometric approach is applied to a nonlinear ship propulsion system benchmark. The calculations and application results are presented in detail to give an illustrative example. The obtained subsystems are considered for the design of nonlinear observers in order to obtain FDI. Additionally, an adaptive...... for the observers designed for the ship propulsion system. Furthermore, it stresses the importance of the time-variant character of the linearization along a trajectory. It leads to a different stability analysis than for linearization at one operation point. Finally, the preliminary concept of (actuator) fault...

  8. Linking Indigenous Knowledge and Observed Climate Change Studies

    Science.gov (United States)

    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.

  9. Implementing earth observation and advanced satellite based atmospheric sounders for water resource and climate modelling

    DEFF Research Database (Denmark)

    Boegh, E.; Dellwik, Ebba; Hahmann, Andrea N.;

    This paper discusses preliminary remote sensing (MODIS) based hydrological modelling results for the Danish island Sjælland (7330 km2) in relation to project objectives and methodologies of a new research project “Implementing Earth observation and advanced satellite based atmospheric sounders...... for effective land surface representation in water resource modeling” (2009- 2012). The purpose of the new research project is to develop remote sensing based model tools capable of quantifying the relative effects of site-specific land use change and climate variability at different spatial scales....... For this purpose, a) internal catchment processes will be studied using a Distributed Temperature Sensing (DTS) system, b) Earth observations will be used to upscale from field to regional scales, and c) at the largest scale, satellite based atmospheric sounders and meso-scale climate modelling will be used...

  10. Unsteady aerodynamic modeling based on POD-observer method

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A new hybrid approach to constructing reduced-order models(ROM)of unsteady aerodynamics applicable to aeroelastic analysis is presented by using proper orthogonal decomposition(POD)in combination with observer techniques.Fluid modes are generated through POD by sampling observations of solutions derived from the full-order model.The response in the POD training is projected onto the fluid modes to determine the time history of the modal amplitudes.The resulting data are used to extract the Markov parameters of the low-dimensional model for modal amplitudes using a related deadbeat observer.The state-space realization is synthesized from the system’s Markov parameters that are processed with the eigensystem realization algorithm.The POD-observer method is applied to a two-dimensional airfoil system in subsonic flow field.The results predicted by the ROM are in general agreement with those from the full-order system.The ROM obtained by the hybrid approach captures the essence of a fluid system and produces vast reduction in both degrees of freedom and computational time relative to the full-order model.

  11. Evidence-Based Novel Changes in Prevalence and Symptom Characteristics of Spleen Deficiency Syndrome in Persons of Varied Health Status and Different Ages: A Cross-Sectional Observational Study

    Directory of Open Access Journals (Sweden)

    Yin Zhang

    2014-01-01

    Full Text Available Deficiency of the organs is a vital pathophysiologic characteristic in the elderly. A core TCM aging theory is known as aging caused by spleen deficiency syndrome (SDS that can be found in ancient and modern literature. The key objectives of this study were to establish a full-scale trial to evaluate the prevalence, symptom severity, frequency, and distribution of SDS in different age groups as related to health status (healthy, subhealthy, and chronic disease to elucidate the role of spleen deficiency in the aging process and deterioration of health status. This cross-sectional observational study was conducted in 4 hospitals in China. 1390 participants aged 20–79 were interviewed by investigators who completed questionnaires recording prevalence, severity, and frequency of symptoms as well as other relevant information. The results revealed that prevalence and symptom characteristics of SDS showed regularities with increasing age and deteriorating health status. It supports the TCM concept that spleen deficiency is an important mechanism of aging, subhealth, and chronic diseases. Early recognition of the warning signs and symptoms of SDS may lead to intervention and even prevention strategies for subhealth and chronic diseases as well as promotion of healthy aging.

  12. Meditation Based Therapies—A Systematic Review and Some Critical Observations

    Directory of Open Access Journals (Sweden)

    Lone Overby Fjorback

    2012-01-01

    Full Text Available This article systematically reviews the evidence for Mindfulness-Based Stress Reduction (MBSR and Mindfulness-Based Cognitive Therapy (MBCT and analyses the conditions around their rising popularity. MBSR, MBCT and Mindfulness Meditation were used as key words. The inclusion criteria were randomized controlled trials using the standard MBSR/MBCT program with a minimum of 33 participants. Twenty four studies were included. MBSR improved mental health in ten studies compared to waitlist control or treatment as usual. Moreover, MBSR was as efficacious as active control group in four studies, and showed a tendency over active control in one study. MBCT reduced the risk of depressive relapse in all five included studies. Evidence supports that MBSR improves mental health and MBCT prevents depressive relapse. It is interesting to observe that meditation based therapy programs are rapidly enjoying popularity. We discuss the cultural and theoretical implications.

  13. Conceptual Research of Lunar-based Earth Observation for Polar Glacier Motion

    Science.gov (United States)

    Ruan, Zhixing; Liu, Guang; Ding, Yixing

    2016-07-01

    The ice flow velocity of glaciers is important for estimating the polar ice sheet mass balance, and it is of great significance for studies into rising sea level under the background of global warming. However so far the long-term and global measurements of these macro-scale motion processes of the polar glaciers have hardly been achieved by Earth Observation (EO) technique from the ground, aircraft or satellites in space. This paper, facing the demand for space technology for large-scale global environmental change observation,especially the changes of polar glaciers, and proposes a new concept involving setting up sensors on the lunar surface and using the Moon as a platform for Earth observation, transmitting the data back to Earth. Lunar-based Earth observation, which enables the Earth's large-scale, continuous, long-term dynamic motions to be measured, is expected to provide a new solution to the problems mentioned above. According to the pattern and characteristics of polar glaciers motion, we will propose a comprehensive investigation of Lunar-based Earth observation with synthetic aperture radar (SAR). Via theoretical modeling and experimental simulation inversion, intensive studies of Lunar-based Earth observation for the glacier motions in the polar regions will be implemented, including the InSAR basics theory, observation modes of InSAR and optimization methods of their key parameters. It will be of a great help to creatively expand the EO technique system from space. In addition, they will contribute to establishing the theoretical foundation for the realization of the global, long-term and continuous observation for the glacier motion phenomena in the Antarctic and the Arctic.

  14. Observer-based output feedback control of discrete-time linear systems with input and output delays

    Science.gov (United States)

    Zhou, Bin

    2014-11-01

    In this paper, we study observer-based output feedback control of discrete-time linear systems with both multiple input and output delays. By generalising our recently developed truncated predictor feedback approach for state feedback stabilisation of discrete-time time-delay systems to the design of observer-based output feedback, two types of observer-based output feedback controllers, one being memory and the other memoryless, are constructed. Both full-order and reduced-order observer-based controllers are established in both the memory and memoryless schemes. It is shown that the separation principle holds for the memory observer-based output feedback controllers, but does not hold for the memoryless ones. We further show that the proposed observer-based output feedback controllers solve both the l2 and l∞ semi-global stabilisation problems. A numerical example is given to illustrate the effectiveness of the proposed approaches.

  15. Neural network-based adaptive controller design of robotic manipulators with an observer.

    Science.gov (United States)

    Sun, F; Sun, Z; Woo, P Y

    2001-01-01

    A neural network (NN)-based adaptive controller with an observer is proposed for the trajectory tracking of robotic manipulators with unknown dynamics nonlinearities. It is assumed that the robotic manipulator has only joint angle position measurements. A linear observer is used to estimate the robot joint angle velocity, while NNs are employed to further improve the control performance of the controlled system through approximating the modified robot dynamics function. The adaptive controller for robots with an observer can guarantee the uniform ultimate bounds of the tracking errors and the observer errors as well as the bounds of the NN weights. For performance comparisons, the conventional adaptive algorithm with an observer using linearity in parameters of the robot dynamics is also developed in the same control framework as the NN approach for online approximating unknown nonlinearities of the robot dynamics. Main theoretical results for designing such an observer-based adaptive controller with the NN approach using multilayer NNs with sigmoidal activation functions, as well as with the conventional adaptive approach using linearity in parameters of the robot dynamics are given. The performance comparisons between the NN approach and the conventional adaptation approach with an observer is carried out to show the advantages of the proposed control approaches through simulation studies.

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

    Directory of Open Access Journals (Sweden)

    María del Mar Alfaya Góngora

    2016-04-01

    Full Text Available 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.

  17. Deep Impact: observations from a worldwide Earth-based campaign.

    Science.gov (United States)

    Meech, K J; Ageorges, N; A'Hearn, M F; Arpigny, C; Ates, A; Aycock, J; Bagnulo, S; Bailey, J; Barber, R; Barrera, L; Barrena, R; Bauer, J M; Belton, M J S; Bensch, F; Bhattacharya, B; Biver, N; Blake, G; Bockelée-Morvan, D; Boehnhardt, H; Bonev, B P; Bonev, T; Buie, M W; Burton, M G; Butner, H M; Cabanac, R; Campbell, R; Campins, H; Capria, M T; Carroll, T; Chaffee, F; Charnley, S B; Cleis, R; Coates, A; Cochran, A; Colom, P; Conrad, A; Coulson, I M; Crovisier, J; deBuizer, J; Dekany, R; de Léon, J; Dello Russo, N; Delsanti, A; DiSanti, M; Drummond, J; Dundon, L; Etzel, P B; Farnham, T L; Feldman, P; Fernández, Y R; Filipovic, M D; Fisher, S; Fitzsimmons, A; Fong, D; Fugate, R; Fujiwara, H; Fujiyoshi, T; Furusho, R; Fuse, T; Gibb, E; Groussin, O; Gulkis, S; Gurwell, M; Hadamcik, E; Hainaut, O; Harker, D; Harrington, D; Harwit, M; Hasegawa, S; Hergenrother, C W; Hirst, P; Hodapp, K; Honda, M; Howell, E S; Hutsemékers, D; Iono, D; Ip, W-H; Jackson, W; Jehin, E; Jiang, Z J; Jones, G H; Jones, P A; Kadono, T; Kamath, U W; Käufl, H U; Kasuga, T; Kawakita, H; Kelley, M S; Kerber, F; Kidger, M; Kinoshita, D; Knight, M; Lara, L; Larson, S M; Lederer, S; Lee, C-F; Levasseur-Regourd, A C; Li, J Y; Li, Q-S; Licandro, J; Lin, Z-Y; Lisse, C M; LoCurto, G; Lovell, A J; Lowry, S C; Lyke, J; Lynch, D; Ma, J; Magee-Sauer, K; Maheswar, G; Manfroid, J; Marco, O; Martin, P; Melnick, G; Miller, S; Miyata, T; Moriarty-Schieven, G H; Moskovitz, N; Mueller, B E A; Mumma, M J; Muneer, S; Neufeld, D A; Ootsubo, T; Osip, D; Pandea, S K; Pantin, E; Paterno-Mahler, R; Patten, B; Penprase, B E; Peck, A; Petitas, G; Pinilla-Alonso, N; Pittichova, J; Pompei, E; Prabhu, T P; Qi, C; Rao, R; Rauer, H; Reitsema, H; Rodgers, S D; Rodriguez, P; Ruane, R; Ruch, G; Rujopakarn, W; Sahu, D K; Sako, S; Sakon, I; Samarasinha, N; Sarkissian, J M; Saviane, I; Schirmer, M; Schultz, P; Schulz, R; Seitzer, P; Sekiguchi, T; Selman, F; Serra-Ricart, M; Sharp, R; Snell, R L; Snodgrass, C; Stallard, T; Stecklein, G; Sterken, C; Stüwe, J A; Sugita, S; Sumner, M; Suntzeff, N; Swaters, R; Takakuwa, S; Takato, N; Thomas-Osip, J; Thompson, E; Tokunaga, A T; Tozzi, G P; Tran, H; Troy, M; Trujillo, C; Van Cleve, J; Vasundhara, R; Vazquez, R; Vilas, F; Villanueva, G; von Braun, K; Vora, P; Wainscoat, R J; Walsh, K; Watanabe, J; Weaver, H A; Weaver, W; Weiler, M; Weissman, P R; Welsh, W F; Wilner, D; Wolk, S; Womack, M; Wooden, D; Woodney, L M; Woodward, C; Wu, Z-Y; Wu, J-H; Yamashita, T; Yang, B; Yang, Y-B; Yokogawa, S; Zook, A C; Zauderer, A; Zhao, X; Zhou, X; Zucconi, J-M

    2005-10-14

    On 4 July 2005, many observatories around the world and in space observed the collision of Deep Impact with comet 9P/Tempel 1 or its aftermath. This was an unprecedented coordinated observational campaign. These data show that (i) there was new material after impact that was compositionally different from that seen before impact; (ii) the ratio of dust mass to gas mass in the ejecta was much larger than before impact; (iii) the new activity did not last more than a few days, and by 9 July the comet's behavior was indistinguishable from its pre-impact behavior; and (iv) there were interesting transient phenomena that may be correlated with cratering physics.

  18. Photometric Observation and Modeling Study of the Asteroid (26) Proserpina

    Science.gov (United States)

    Bin, Li; Hai-bin, Zhao; Xin, Wang

    2016-07-01

    We present the new CCD observations on the asteroid (26) Proserpina performed between 2011 December and 2012 February. Based upon the new observations, a synodic rotation period of (13.107 ± 0.002) h is obtained. Using all the light curves available sofar, the rotation vector, rotation period, and the shape model of the asteroid are determined with the convex-hull inversion method. Further more, a bootstrap method is applied to estimating the uncertainties of the rotation parameters. We derive a pair of possible rotation poles for (26) Proserpina, and believe that it has a retrograde rotation. The rotation poles are determined to be λ1 = 90.8° ± 1.4°, β1 = -53.1° ± 3.2°, and λ2 = 259.3° ± 2.2°, β2 = -62.0° ± 2.0°. The sidereal rotation periods corresponding to the two poles are almost the same as (13.109777 ± 3.8 × 10-6) h. And corresponding to this pair of rotation poles, the convex-hull shapes of the asteroid are the mirror images of each other.

  19. Space-Based Gravitational-Wave Observations as Tools for Testing General Relativity

    Science.gov (United States)

    Will, Clifford M.

    2004-01-01

    We continued a project, to analyse the ways in which detection and study of gravitational waves could provide quantitative tests of general relativity, with particular emphasis on waves that would be detectable by space-based observatories, such as LISA. This work had three foci: 1) Tests of scalar-tensor theories of gravity that, could be done by analyzing gravitational waves from neutron stars inspiralling into massive black holes, as detectable by LISA; 2) Study of alternative theories of gravity in which the graviton could be massive, and of how gravitational-wave observations by space-based detectors, solar-system tests, and cosmological observations could constrain such theories; and 3) Study of gravitational-radiation back reaction of particles orbiting black holes in general relativity, with emphasis on the effects of spin.

  20. Pandemrix™ and narcolepsy: A critical appraisal of the observational studies.

    Science.gov (United States)

    Verstraeten, Thomas; Cohet, Catherine; Dos Santos, Gaël; Ferreira, Germano Lc; Bollaerts, Kaatje; Bauchau, Vincent; Shinde, Vivek

    2016-01-01

    A link between Pandemrix™ (AS03-adjuvanted H1N1 pandemic influenza vaccine, GSK Vaccines, Belgium) and narcolepsy was first suspected in 2010 in Sweden and Finland following a number of reports in children and adolescents. Initial scepticism about the reported association faded as additional countries reported similar findings, leading several regulatory authorities to restrict the use of Pandemrix™. The authors acknowledge that currently available data suggest an increased risk of narcolepsy following vaccination with Pandemrix™; however, from an epidemiologist's perspective, significant methodological limitations of the studies have not been fully addressed and raise questions about the reported risk estimates. We review the most important biases and confounders that potentially occurred in 12 European studies of the observed association between Pandemrix™ and narcolepsy, and call for further analyses and debate.

  1. Complete control, direct observation and study of molecular super rotors

    CERN Document Server

    Korobenko, Aleksey; Milner, Valery

    2013-01-01

    Extremely fast rotating molecules carrying significantly more energy in their rotation than in any other degree of freedom are known as "super rotors". It has been speculated that super rotors may exhibit a number of unique and intriguing properties. Theoretical studies showed that ultrafast molecular rotation may change the character of molecular scattering from solid surfaces, alter molecular trajectories in external fields, make super rotors surprisingly stable against collisions, and lead to the formation of gas vortices. New ways of molecular cooling and selective chemical bond breaking by ultrafast spinning have been proposed. Owing to the fundamental laws of nature, bringing a large number of molecules to fast, directional and synchronous rotation is rather challenging. As a result, only indirect evidence of super rotors has been reported to date. Here we demonstrate the first controlled creation, direct observation and study of molecular super rotors. Using intense laser pulses tailored to produce an ...

  2. A video-based observation method to assess musculoskeletal load in kitchen work.

    Science.gov (United States)

    Pehkonen, Irmeli; Ketola, Ritva; Ranta, Riikka; Takala, Esa-Pekka

    2009-01-01

    This paper describes a new video-based observation method aimed to assess musculoskeletal load in kitchen work, aspects of its repeatability and validity, and problems confronted by the observers. Two pairs of researchers observed individually 117 video clips recorded in kitchens. Interobserver repeatability was assessed by computing the proportion of agreement and weighted kappa values (kappa(w)). Validity was analyzed by studying the distribution of the assessments over the rating scales and the ratings before and after the interventions, which were compared with expert assessments made from the same intervention targets. The proportion of agreement ranged from 57 to 88%. Interobserver repeatability based on weighted kappa values was mainly good to moderate. The method detected the changes in physical load due to the interventions. Direction of the changes corresponded with the expert assessments. Further development of the method is needed to assess the load on the hands and wrists.

  3. Observations on Experience and Flow in Movement-Based Interaction

    NARCIS (Netherlands)

    Nijholt, Anton; Pasch, Marco; Dijk, van Betsy; Reidsma, Dennis; Heylen, Dirk; England, David

    2011-01-01

    Movement-based interfaces assume that their users move. Users have to perform exercises, they have to dance, they have to golf or football, or they want to train particular bodily skills. Many examples of those interfaces exist, sometimes asking for subtle interaction between user and interface and

  4. Observer-based H-infinity output feedback control with feedback gain and observer gain variations for Delta operator system

    Institute of Scientific and Technical Information of China (English)

    Ruiquan LIN; Fuwen YANG; Renchong PENG

    2009-01-01

    Considering that the controller feedback gain and the observer gain are of additive norm-bounded variations, a design method of observer-based H-infinity output feedback controller for uncertain Delta operator systems is proposed in this paper. A sufficient condition of such controllers is presented in linear matrix inequality (LMI) forms. A numerical example is then given to illustrate the effectiveness of this method, that is, the obtained controller guarantees the closed-loop system asymptotically stable and the expected H-infinity performance even if the controller feedback gain and the observer gain are varied.

  5. Partially observable Markov decision processes for risk-based screening

    Science.gov (United States)

    Mrozack, Alex; Liao, Xuejun; Skatter, Sondre; Carin, Lawrence

    2016-05-01

    A long-term goal for checked baggage screening in airports has been to include passenger information, or at least a predetermined passenger risk level, in the screening process. One method for including that information could be treating the checked baggage screening process as a system-of-systems. This would allow for an optimized policy builder, such as one trained using the methodology of partially observable Markov decision processes (POMDP), to navigate the different sensors available for screening. In this paper we describe the necessary steps to tailor a POMDP for baggage screening, as well as results of simulations for specific screening scenarios.

  6. NOISY OBSERVATION BASED STABILIZATION AND OPTIMIZATION FOR UNKNOWN SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    CHEN Hanfu(Han-Fu Chen)

    2003-01-01

    The paper addresses optimization of a performance function which either is optimized via stabilizing and controlling the underlying unknown system or is directly optimized on the basis of its noise-corrupted observations. For the first case the unknown system is identified and then the indirect adaptive control approach is applied to optimize the performance function. For the second case the stochastic approximation method is used to optimize the objective function, and it appears that a number of problems arising from applications may be reduced to the one solvable by this approach. The paper demonstrates some basic results in the area, but with no intention to give a complete survey.

  7. Observer Based Sliding Mode Attitude Control: Theoretical and Experimental Results

    Directory of Open Access Journals (Sweden)

    U. Jørgensen

    2011-07-01

    Full Text Available In this paper we present the design of a sliding mode controller for attitude control of spacecraft actuated by three orthogonal reaction wheels. The equilibrium of the closed loop system is proved to be asymptotically stable in the sense of Lyapunov. Due to cases where spacecraft do not have angular velocity measurements, an estimator for the generalized velocity is derived and asymptotic stability is proven for the observer. The approach is tested on an experimental platform with a sphere shaped Autonomous Underwater Vehicle SATellite: AUVSAT, developed at the Norwegian University of Science and Technology.

  8. Observation-based correction of dynamical models using thermostats

    Science.gov (United States)

    Frank, Jason; Leimkuhler, Benedict

    2017-01-01

    Models used in simulation may give accurate short-term trajectories but distort long-term (statistical) properties. In this work, we augment a given approximate model with a control law (a ‘thermostat’) that gently perturbs the dynamical system to target a thermodynamic state consistent with a set of prescribed (possibly evolving) observations. As proof of concept, we provide an example involving a point vortex fluid model on the sphere, for which we show convergence of equilibrium quantities (in the stationary case) and the ability of the thermostat to dynamically track a transient state. PMID:28265197

  9. Space-Based Observations of Satellites From the MOST Microsatellite

    Science.gov (United States)

    2006-11-01

    observations spatiales canadiennes d’un objet en orbite terrestre . Deux satellites de géolocalisation GPS ont été suivis à l’aide du télescope optique monté...the derived orbital metric data with high precision ephemerides yielded root mean square errors of 13 arcseconds. The errors are shown to result...space surveillance from an orbiting platform. Résumé Le 12 octobre 2005, le microsatellite MOST du Canada a acquis les premières images

  10. A statistical study of giant molecular clouds traced by 13CO, C18O, CS, and CH3OH in the disk of NGC 1068 based on ALMA observations

    Science.gov (United States)

    Tosaki, Tomoka; Kohno, Kotaro; Harada, Nanase; Tanaka, Kunihiko; Egusa, Fumi; Izumi, Takuma; Takano, Shuro; Nakajima, Taku; Taniguchi, Akio; Tamura, Yoichi

    2017-01-01

    We present 1{^''.}4 (98 pc) resolution ALMA observations of 13CO(J = 1-0), C18O(J = 1-0), CS(J = 2-1), and CH3OH(JK = 2K-1K) molecular rotational lines in the central 1' (4.2 kpc) diameter region of NGC 1068 to study the physical and chemical properties of giant molecular clouds (GMCs) and to test whether these GMC-scale properties are linked to the larger-scale galactic environment. Using the derived 13CO cube, we have identified 187 high-significance (>8 σ) GMCs by employing the CLUMPFIND algorithm. The molecular gas masses of GMCs (M_^{13CO}), derived from the 13CO data, range from 1.8 × 104 M⊙ to 4.2 × 107 M⊙. A mass function of GMCs in NGC 1068 has been obtained for the first time at ˜100 pc resolution. We find the slope of the mass function γ = -1.25 ± 0.07 for a mass range of M_^{13CO} ≥ 105 M⊙. This is shallower than the GMCs in the disk regions of the Milky Way, M 51, and NGC 300. Further, we find that the high mass cut-off of the GMC mass function occurs at M_^{13CO} ˜ 6 × 107 M⊙, which is an order of magnitude larger than that in the nuclear bar region of M 51, indicating that the more massive clouds dominate the mass budget in NGC 1068. The observed C18O(J = 1-0)/13CO(J = 1-0) intensity ratios are found to be fairly uniform (0.27 ± 0.05) among the identified GMCs. In contrast, the CH3OH(JK = 2K-1K)/13CO(J = 1-0) ratios exhibit striking spatial variation across the disk, with the smallest values around the bar-end (<0.03), and larger ratios along the spiral arms (˜0.1-0.2). We find that GMCs with detectable methanol emission tend to have systematically larger velocity widths than those without methanol emission, suggesting that (relatively weak) shocks are responsible for the enhancement of the CH3OH/13CO ratios of GMCs in the disk of NGC 1068.

  11. Sensorless DC motor drive via optimal observer-based servo control

    Energy Technology Data Exchange (ETDEWEB)

    Thananchai Keephakpreeda [Thammasat University (Thailand). School of Industrial and Mechanical Engineering

    2002-07-01

    This paper proposes an alternative design of a sensorless DC motor drive via optimal observer-based servo control. Without the speed sensor, the extended Luenberger observer is implemented to estimate the rotor speed of the DC motor in the presence of the disturbance torque. With this knowledge of the speed estimated from the observer, the servo state-feedback controller can drive such a rotor speed to follow the desired one. The stability and performance of the DC drive system can be guaranteed by the optimal control which minimizes the H{sub 2} norm of the closed-loop feedback control and observer system. The simulation and experimental studies are demonstrated for the effectiveness of the proposed control methodology in a practical approach for the sensorless DC drive. (author)

  12. Observer-based robust H-infinity control for uncertain switched systems

    Institute of Scientific and Technical Information of China (English)

    Zhengyi SONG; Jun ZHAO

    2007-01-01

    The problem of observer-based robust H-infinity control is addressed for a class of linear discrete-time switched systems with time-varying norm-bounded uncertainties by using switched Lyapunov function method. None of the individual subsystems is assumed to be robustly H-infinity solvable. A novel switched Lypunov function matrix with diagonal-block form is devised to overcome the difficulties in designing switching laws. For robust H-infinity stability analysis, two linear-matrix-inequality-based sufficient conditions are derived by only using the smallest region function strategy if some parameters are preselected. Then, the robust H-infinity control synthesis is studied using a switching state feedback and an observer-based switching dynamical output feedback. All the switching laws are simultaneously constructively designed. Finally, a simulation example is given to illustrate the validity of the results.

  13. Mucocutaneous manifestations of acquired hypoparathyroidism: An observational study

    Directory of Open Access Journals (Sweden)

    Somenath Sarkar

    2012-01-01

    Full Text Available 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.

  14. A Kalman Filter for SINS Self-Alignment Based on Vector Observation.

    Science.gov (United States)

    Xu, Xiang; Xu, Xiaosu; Zhang, Tao; Li, Yao; Tong, Jinwu

    2017-01-29

    In this paper, a self-alignment method for strapdown inertial navigation systems based on the q-method is studied. In addition, an improved method based on integrating gravitational apparent motion to form apparent velocity is designed, which can reduce the random noises of the observation vectors. For further analysis, a novel self-alignment method using a Kalman filter based on adaptive filter technology is proposed, which transforms the self-alignment procedure into an attitude estimation using the observation vectors. In the proposed method, a linear psuedo-measurement equation is adopted by employing the transfer method between the quaternion and the observation vectors. Analysis and simulation indicate that the accuracy of the self-alignment is improved. Meanwhile, to improve the convergence rate of the proposed method, a new method based on parameter recognition and a reconstruction algorithm for apparent gravitation is devised, which can reduce the influence of the random noises of the observation vectors. Simulations and turntable tests are carried out, and the results indicate that the proposed method can acquire sound alignment results with lower standard variances, and can obtain higher alignment accuracy and a faster convergence rate.

  15. Extended State Observer based control for coaxial-rotor UAV.

    Science.gov (United States)

    Rida Mokhtari, M; Choukchou Braham, Amal; Cherki, Brahim

    2016-03-01

    This paper considers the problem of controlling the position and the orientation of a Coaxial-Rotor Unmanned Aerial Vehicle -CRUAV- despite unknown aerodynamic efforts. A hierarchical flight controller is designed, allowing the trajectory tracking and the stabilization of the vehicle. The designed controller is build through a hierarchical approach yielding two control loops, an inner one to control the attitude and an outer one to control the translational trajectory of the rotorcraft. An Extended State Observer -ESO- is used to estimate the state and the unknown aerodynamic disturbances. The analysis further extends to the design of a control law that takes the disturbance estimation procedure into account. Numerical simulations are carried out to demonstrate the efficiency of the proposed control strategy.

  16. Critical Observation on Methodologies of Select Doctoral Research Studies

    Directory of Open Access Journals (Sweden)

    Dr Indrajit Goswami

    2014-12-01

    Full Text Available The present article aims to critically observe and interpret the methodological deficiencies as found in randomly selected 14 doctoral theses submitted to two different universities in India. Despite their serious deviation from the expected methodological standards, all those theses were accepted and approved by the universities and scholars concerned conferred with PhD degrees. Undoubtedly, those theses kept in the reference sections at the respective university libraries would potentially misguide and mislead the future researchers. Some of the common technical deficiencies, as have been noticed, include (1 absence of careful thoughts in framing research titles, (ii biased method of data collection, (ii absence of logical explanation in favour of sample size and sample selection process, (iii designing and execution of instrument for data collection, (iv theory formulation in terms of framing of objectives, hypotheses and operational definitions etc. The article attempts to present the critical observations on case-to-case basis so that their conceptual, instrumental and procedural deficiencies and deviations are easily understood by the academicians, researchers and students. The content of this article is divided in to three broad sections. The first section deals with an introduction to quantitative and qualitative research methods and their advantages and limitations. The next section deals with the review of the selected theses followed by conclusion and suggested remedial measures. The objective of this article is purely academic and its scope is limited to enhancement of quality of future research studies in the domains and related fields.

  17. Providers' response to child eating behaviors: A direct observation study.

    Science.gov (United States)

    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.

  18. Nursing diagnoses in patients with chronic venous ulcer: observational study

    Directory of Open Access Journals (Sweden)

    Glycia de Almeida Nogueira

    2015-06-01

    Full Text Available This study aimed to analyze nursing diagnoses in people with chronic venous ulcer. An observational, descriptive, quantitative research conducted in an ambulatory specialized in wound treatment, with a non-probabilistic sample of 20 patients.  Data collection was performed in an institutional form denominated Assessment Protocol for Clients with Tissue Lesions. Diagnoses were established by consensus among four researchers with experience in nursing diagnoses and wound treatments. From data analysis, 16 diagnoses were identified, with 100% of participants presenting: Impaired tissue integrity, Ineffective peripheral tissue perfusion, Risk of infection, Impaired physical mobility and Ineffective health self-control. These diagnoses are found in Safety/Protection, Activity/Rest and Health promotion domains, which from the clinical practice stand point should be priority focuses in nursing intervention and assessment.

  19. PolarBase: a data base of high resolution spectropolarimetric stellar observations

    CERN Document Server

    Petit, P; Théado, S; Paletou, F; Manset, N; Morin, J; Marsden, S C; Jeffers, S V

    2014-01-01

    PolarBase is an evolving data base that contains all stellar data collected with the ESPaDOnS and NARVAL high-resolution spectropolarimeters, in their reduced form, as soon as they become public. As of early 2014, observations of 2,000 stellar objects throughout the Hertzsprung-Russell diagram are available. Intensity spectra are available for all targets, and the majority of the observations also include simultaneous spectra in circular or linear polarization, with the majority of the polarimetric measurements being performed only in circularly polarized light (Stokes V). Observations are associated with a cross-correlation pseudo-line profile in all available Stokes parameters, greatly increasing the detectability of weak polarized signatures. Stokes V signatures are detected for more than 300 stars of all masses and evolutionary stages, and linear polarization is detected in 35 targets. The detection rate in Stokes V is found to be anti-correlated with the stellar effective temperature. This unique set of ...

  20. Molecular Carbon in the Galaxy: Laboratory and Observational Studies

    Science.gov (United States)

    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.

  1. Atmospheric contamination for CMB ground-based observations

    CERN Document Server

    Errard, J; Akiba, Y; Arnold, K; Atlas, M; Baccigalupi, C; Barron, D; Boettger, D; Borrill, J; Chapman, S; Chinone, Y; Cukierman, A; Delabrouille, J; Dobbs, M; Ducout, A; Elleflot, T; Fabbian, G; Feng, C; Feeney, S; Gilbert, A; Goeckner-Wald, N; Halverson, N W; Hasegawa, M; Hattori, K; Hazumi, M; Hill, C; Holzapfel, W L; Hori, Y; Inoue, Y; Jaehnig, G C; Jaffe, A H; Jeong, O; Katayama, N; Kaufman, J; Keating, B; Kermish, Z; Keskitalo, R; Kisner, T; Jeune, M Le; Lee, A T; Leitch, E M; Leon, D; Linder, E; Matsuda, F; Matsumura, T; Miller, N J; Myers, M J; Navaroli, M; Nishino, H; Okamura, T; Paar, H; Peloton, J; Poletti, D; Puglisi, G; Rebeiz, G; Reichardt, C L; Richards, P L; Ross, C; Rotermund, K M; Schenck, D E; Sherwin, B D; Siritanasak, P; Smecher, G; Stebor, N; Steinbach, B; Stompor, R; Suzuki, A; Tajima, O; Takakura, S; Tikhomirov, A; Tomaru, T; Whitehorn, N; Wilson, B; Yadav, A; Zahn, O

    2015-01-01

    Atmosphere is one of the most important noise sources for ground-based Cosmic Microwave Background (CMB) experiments. By increasing optical loading on the detectors, it amplifies their effective noise, while its fluctuations introduce spatial and temporal correlations between detected signals. We present a physically motivated 3d-model of the atmosphere total intensity emission in the millimeter and sub-millimeter wavelengths. We derive an analytical estimate for the correlation between detectors time-ordered data as a function of the instrument and survey design, as well as several atmospheric parameters such as wind, relative humidity, temperature and turbulence characteristics. Using numerical computation, we examine the effect of each physical parameter on the correlations in the time series of a given experiment. We then use a parametric-likelihood approach to validate the modeling and estimate atmosphere parameters from the POLARBEAR-I project first season data set. We compare our results to previous st...

  2. Entamoeba histolytica: observations on metabolism based on thegenome sequence

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Iain J.; Loftus, Brendan J.

    2005-07-01

    The sequencing of the genome of Entamoeba histolytica has allowed a reconstruction of its metabolic pathways, many of which are unusual for a eukaryote. Based on the genome sequence, it appears that amino acids may play a larger role than previously thought in energy metabolism, with roles in both ATP synthesis and NAD regeneration. Arginine decarboxylase may be involved in survival of E. histolytica during its passage through the stomach. The usual pyrimidine synthesis pathway is absent, but a partial pyrimidine degradation pathway could be part of a novel pyrimidine synthesis pathway. Ribonucleotide reductase was not found in the E. histolytica genome, but it was found in the close relatives Entamoeba invadens and Entamoeba moshkovskii, suggesting a recent loss from E. histolytica. The usual eukaryotic glucose transporters are not present, but members of a prokaryotic monosaccharide transporter family are present.

  3. Statistical region-based active contours with exponential family observations

    CERN Document Server

    Lecellier, François; Fadili, Jalal; Aubert, Gilles; Revenu, Marinette

    2008-01-01

    In this paper, we focus on statistical region-based active contour models where image features (e.g. intensity) are random variables whose distribution belongs to some parametric family (e.g. exponential) rather than confining ourselves to the special Gaussian case. Using shape derivation tools, our effort focuses on constructing a general expression for the derivative of the energy (with respect to a domain) and derive the corresponding evolution speed. A general result is stated within the framework of multi-parameter exponential family. More particularly, when using Maximum Likelihood estimators, the evolution speed has a closed-form expression that depends simply on the probability density function, while complicating additive terms appear when using other estimators, e.g. moments method. Experimental results on both synthesized and real images demonstrate the applicability of our approach.

  4. Model-based reinforcement learning for partially observable games with sampling-based state estimation.

    Science.gov (United States)

    Fujita, Hajime; Ishii, Shin

    2007-11-01

    Games constitute a challenging domain of reinforcement learning (RL) for acquiring strategies because many of them include multiple players and many unobservable variables in a large state space. The difficulty of solving such realistic multiagent problems with partial observability arises mainly from the fact that the computational cost for the estimation and prediction in the whole state space, including unobservable variables, is too heavy. To overcome this intractability and enable an agent to learn in an unknown environment, an effective approximation method is required with explicit learning of the environmental model. We present a model-based RL scheme for large-scale multiagent problems with partial observability and apply it to a card game, hearts. This game is a well-defined example of an imperfect information game and can be approximately formulated as a partially observable Markov decision process (POMDP) for a single learning agent. To reduce the computational cost, we use a sampling technique in which the heavy integration required for the estimation and prediction can be approximated by a plausible number of samples. Computer simulation results show that our method is effective in solving such a difficult, partially observable multiagent problem.

  5. Wave energy resource assessment based on satellite observations around Indonesia

    Science.gov (United States)

    Ribal, Agustinus; Zieger, Stefan

    2016-06-01

    A preliminary assessment of wave energy resource around Indonesian's ocean has been carried out by means of analyzing satellite observations. The wave energy flux or wave power can be approximated using parameterized sea states. Wave power scales with significant wave height, characteristic wave period and water depth. In this approach, the significant wave heights were obtained from ENVISAT (Environmental Satellite) data which have been calibrated. However, as the characteristic wave period is rarely specified and therefore must be estimated from other variables when information about the wave spectra is unknown. Here, the characteristic wave period was calculated with an empirical model that utilizes altimeter estimates of wave height and backscatter coefficient originally proposed. For the Indonesian region, wave power energy is calculated over two periods of one year each and was compared with the results from global hindcast carried out with a recent release of wave model WAVEWATCH III. We found that, the most promising wave power energy regions around the Indonesian archipelago are located in the south of Java island and the south west of Sumatera island. In these locations, about 20 - 30 kW/m (90th percentile: 30-50 kW/m, 99th percentile: 40-60 kW/m) wave power energy on average has been found around south of Java island during 2010. Similar results have been found during 2011 at the same locations. Some small areas which are located around north of Irian Jaya (West Papua) are also very promising and need further investigation to determine its capacity as a wave energy resource.

  6. Foot Length, Chest Circumference, and Mid Upper Arm Circumference Are Good Predictors of Low Birth Weight and Prematurity in Ethnic Minority Newborns in Vietnam: A Hospital-Based Observational Study.

    Directory of Open Access Journals (Sweden)

    Hai Nguyen Thi

    Full Text Available The evaluation of tools to accurately identify low birth weight (LBW and/or premature newborns in resource-limited countries is a research priority. We explored the use of foot length, chest circumference, and mid-upper arm circumference (MUAC measured within 24 h as diagnostic tools for identifying newborns who are LBW, premature, or both; and compared measurements taken at birth with those taken at five days of age.An observational study was undertaken in Hoa Binh Province General Hospital, Vietnam, in ethnic minority newborns. Birth weight, foot length, chest circumference, and MUAC were measured within 24 h of birth and in a subset of 200, were repeated on day five of life. Gestational age was estimated using the New Ballard Score. Receiver Operating Characteristic curves and optimal cut-points (the point with the highest sensitivity and specificity where the sensitivity was at least 0.8 were calculated, for predicting prematurity, LBW, and both. Measurements within 24 h and at five days of life were compared.485 newborns were recruited. Chest circumference and MUAC measured within 24 h of birth were found to be highly predictive of LBW (both yielding area under the curve [AUC] of 0.98, 95% confidence interval [CI] 0.96-0.99, and performed marginally better than foot length (AUC 0.94, 95%CI 0.92-0.96. The optimal cut-points for measurements within 24 h of birth were ≤ 7.4 cm for foot length; ≤ 30.4 cm for chest circumference; and ≤ 9.0 cm for MUAC. There was statistical evidence that anthropometric measurements taken within 24 h of birth were higher than measurements on day five (p<0.02 for all anthropometric measurements but the magnitude of these differences was small (at most 2mm.All measurements taken within 24 h of birth were good predictors of LBW, prematurity and both. Differences in measurements taken within 24 h and on day five were not clinically relevant. Further research will ensure that the application of these measures is

  7. Observation of Neutron Skyshine from an Accelerator Based Neutron Source

    Energy Technology Data Exchange (ETDEWEB)

    Franklyn, C. B. [Radiation Science Department, Necsa, PO Box 582, Pretoria 0001 (South Africa)

    2011-12-13

    A key feature of neutron based interrogation systems is the need for adequate provision of shielding around the facility. Accelerator facilities adapted for fast neutron generation are not necessarily suitably equipped to ensure complete containment of the vast quantity of neutrons generated, typically >10{sup 11} n{center_dot}s{sup -1}. Simulating the neutron leakage from a facility is not a simple exercise since the energy and directional distribution can only be approximated. Although adequate horizontal, planar shielding provision is made for a neutron generator facility, it is sometimes the case that vertical shielding is minimized, due to structural and economic constraints. It is further justified by assuming the atmosphere above a facility functions as an adequate radiation shield. It has become apparent that multiple neutron scattering within the atmosphere can result in a measurable dose of neutrons reaching ground level some distance from a facility, an effect commonly known as skyshine. This paper describes a neutron detection system developed to monitor neutrons detected several hundred metres from a neutron source due to the effect of skyshine.

  8. Theoretical validation of ground-based microwave ozone observations

    Directory of Open Access Journals (Sweden)

    P. Ricaud

    Full Text Available Ground-based microwave measurements of the diurnal and seasonal variations of ozoneat 42±4.5 and 55±8 km are validated by comparing with results from a zero-dimensional photochemical model and a two-dimensional (2D chemical/radiative/dynamical model, respectively. O3 diurnal amplitudes measured in Bordeaux are shown to be in agreement with theory to within 5%. For the seasonal analysis of O3 variation, at 42±4.5 km, the 2D model underestimates the yearly averaged ozone concentration compared with the measurements. A double maximum oscillation (~3.5% is measured in Bordeaux with an extended maximum in September and a maximum in February, whilst the 2D model predicts only a single large maximum (17% in August and a pronounced minimum in January. Evidence suggests that dynamical transport causes the winter O3 maximum by propagation of planetary waves, phenomena which are not explicitly reproduced by the 2D model. At 55±8 km, the modeled yearly averaged O3 concentration is in very good agreement with the measured yearly average. A strong annual oscillation is both measured and modeled with differences in the amplitude shown to be exclusively linked to temperature fields.

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

    Science.gov (United States)

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

    2016-01-01

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

  10. Study of the NWC electrons belt observed on DEMETER Satellite

    CERN Document Server

    Li, Xinqiao; Wang, Ping; Wang, Huanyu; Lu, Hong; Zhang, Xuemin; Huang, Jianping; Shi, Feng; Yu, Xiaoxia; Xu, Yanbing; Meng, Xiangcheng; Wang, Hui; Zhao, Xiaoyun; Parrot, M

    2010-01-01

    We analyzed the data from 2007 to 2008, which is observed by IDP onboard DEMETER satellite, during ten months of NWC working and seven months of NWC shutdown. The characteristic of the space instantaneous electron belts, which come from the influence of the VLF transmitted by NWC, is studied comprehensively. The main distribution region of the NWC electron belts and the flux change are given. We also studied the distribution characteristic of the average energy spectrum in different magnetic shell at the height of DEMETER orbit and the difference of the average energy spectrum of the electrons in the drift loss-cone between day and night. As a result, the powerful power of NWC transmitter and the 19.8 kHz narrow bandwidth VLF emission not only created a momentary electrons enhancement region, which strides 180 degree in them longitude direction and from 1.6 to 1.9 in L value, with the rise of the electrons flux reaching to 3 orders of magnitude mostly, but also induced the enhancement or loss of electrons in ...

  11. 2D vs. 3D mammography observer study

    Science.gov (United States)

    Fernandez, James Reza F.; Hovanessian-Larsen, Linda; Liu, Brent

    2011-03-01

    Breast cancer is the most common type of non-skin cancer in women. 2D mammography is a screening tool to aid in the early detection of breast cancer, but has diagnostic limitations of overlapping tissues, especially in dense breasts. 3D mammography has the potential to improve detection outcomes by increasing specificity, and a new 3D screening tool with a 3D display for mammography aims to improve performance and efficiency as compared to 2D mammography. An observer study using a mammography phantom was performed to compare traditional 2D mammography with this ne 3D mammography technique. In comparing 3D and 2D mammography there was no difference in calcification detection, and mass detection was better in 2D as compared to 3D. There was a significant decrease in reading time for masses, calcifications, and normals in 3D compared to 2D, however, as well as more favorable confidence levels in reading normal cases. Given the limitations of the mammography phantom used, however, a clearer picture in comparing 3D and 2D mammography may be better acquired with the incorporation of human studies in the future.

  12. Recognising advancing nursing practice: evidence from two observational studies.

    Science.gov (United States)

    Wilson-Barnett, J; Barriball, K L; Reynolds, H; Jowett, S; Ryrie, I

    2000-10-01

    Debates over title, grades and relationships across the profession has tended to dominate the literature in advancing nursing practice. Fewer research projects have attempted to study the activities of nurses who are designated as undertaking advancing nursing roles. One study evaluating Masters courses for Clinical Nursing Practice and a second addressing the impact of the 'Scope of Professional Practice' (United Kingdom Central Council for Nursing, Midwifery & Health Visiting, 1992) document by this team of authors afforded these research opportunities. In this paper empirical data from 'reflective' observation with 19 nurses (including midwives and health visitors) are presented to illustrate the range and type of functions undertaken by a small group of practitioners developing their practice. A number of characteristic features emerged. Assessment of individual and group needs, positive motivation to constantly improve practice, inter-disciplinary and cross agency working for planned change and an ability to identify and prioritize service requirements were recognised in these nurses' roles. Certain personal attributes were seen to be essential for successful role development such as confidence, commitment and problem solving powers combined with a positive working environment and supportive managers.

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

    DEFF Research Database (Denmark)

    Ankarfeldt, Mikkel Z; Angquist, Lars; Stocks, Tanja;

    2014-01-01

    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......: 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...

  14. Synchronized observations by using the STEREO and the largest ground-based decametre radio telescope

    Science.gov (United States)

    Konovalenko, A. A.; Stanislavsky, A. A.; Rucker, H. O.; Lecacheux, A.; Mann, G.; Bougeret, J.-L.; Kaiser, M. L.; Briand, C.; Zarka, P.; Abranin, E. P.; Dorovsky, V. V.; Koval, A. A.; Mel'nik, V. N.; Mukha, D. V.; Panchenko, M.

    2013-08-01

    We consider the approach to simultaneous (synchronous) solar observations of radio emission by using the STEREO-WAVES instruments (frequency range 0.125-16 MHz) and the largest ground-based low-frequency radio telescope. We illustrate it by the UTR-2 radio telescope implementation (10-30 MHz). The antenna system of the radio telescope is a T-shape-like array of broadband dipoles and is located near the village Grakovo in the Kharkiv region (Ukraine). The third observation point on the ground in addition to two space-based ones improves the space-mission performance capabilities for the determination of radio-emission source directivity. The observational results from the high sensitivity antenna UTR-2 are particularly useful for analysis of STEREO data in the condition of weak event appearances during solar activity minima. In order to improve the accuracy of flux density measurements, we also provide simultaneous observations with a large part of the UTR-2 radio telescope array and its single dipole close to the STEREO-WAVES antennas in sensitivity. This concept has been studied by comparing the STEREO data with ground-based records from 2007-2011 and shown to be effective. The capabilities will be useful in the implementation of new instruments (LOFAR, LWA, MWA, etc.) and during the future Solar Orbiter mission.

  15. Current problems of dynamics of moons of planets and binary asteroids based on observations

    Science.gov (United States)

    Emel'yanov, N. V.

    2017-01-01

    The general approach to studying the dynamics of moons of planets and asteroids consists in developing more and more accurate models of motion based on observational data. Not only the necessary ephemerides, but also some physical parameters of planets and moons are obtained this way. It is demonstrated in the present study that progress in this field is driven not only by the increase in accuracy of observations. The accuracy of ephemerides may be increased by expanding the observation time interval. Several problems arise on the way toward this goal. Some of them become apparent only when the procedure of observational data processing and use is examined in detail. The method used to derive astrometric data by processing the results of photometric observations of mutual occultations and eclipses of planetary moons is explained below. The primary contribution to the error of astrometric results is produced by the unaccounted noise level in photometric readings and the inaccuracy of received values of the albedo of moons. It is demonstrated that the current methods do not allow one to eliminate the noise completely. Extensive additional photometric measurements should be performed at different angles of rotation of moons and in different spectral bands of the visible wavelength range in order to obtain correct values of the albedo of moons. Many new distant moons of the major planets have been discovered in the early 21st century. However, the observations of these moons are scarce and were performed over short time intervals; as a result, some of the moons were lost. The necessity of further observations of these Solar System bodies is pointed out in the present study. Insufficient knowledge of asteroid masses is an obstacle to improving the accuracy of the ephemerides of Mars. The basic method for determining the masses of large asteroids consists in analyzing their influence on the motion of Mars, the Earth, and spacecraft. The masses of more than 100 large

  16. Profiling float-based observations of net respiration beneath the mixed layer

    Science.gov (United States)

    Hennon, Tyler D.; Riser, Stephen C.; Mecking, Sabine

    2016-06-01

    We employ profiling floats with dissolved oxygen sensors to observe in situ temporal oxygen evolution below the mixed layer, allowing us to characterize net respiration of organic carbon in eight distinct regions over the globe. Export and export efficiency are generally high in locations with strong seasonal variability and low in locations of weak seasonality. Vertically integrated respiration is weakly, yet significantly, correlated with remote observations of chlorophyll, net primary production, and planktonic community size structure. These correlations suggest that regimes of high net primary production and large phytoplankton fuel elevated respiration at depth. Several regions of float-based observations intersect with sites of other detailed observations (e.g., Hawaii and Sargasso Sea), which allows us to compare our results to independent studies. We find that there is good agreement among export production estimates at highly seasonal locations, and that float-based observations may be biased low at weakly seasonal locations. We posit that the reason for the low-latitude discrepancy is the relative steady state of oxygen concentration caused by weak seasonality and shallow wintertime mixed layer depths.

  17. 24 Hours in the Children's Section: An Observational Study at the Public Library

    Science.gov (United States)

    Becker, Katherine

    2012-01-01

    The purpose of this study was to explore patronage and usage of the children's section of a public library. Patrons of the children's section of a public library in a small Northern Arizona city were observed for a total of 24 h over 12 sessions. Analytic induction was used to formulate categories based on field notes made during these…

  18. Runge-Kutta model-based nonlinear observer for synchronization and control of chaotic systems.

    Science.gov (United States)

    Beyhan, Selami

    2013-07-01

    This paper proposes a novel nonlinear gradient-based observer for synchronization and observer-based control of chaotic systems. The model is based on a Runge-Kutta model of the chaotic system where the evolution of the states or parameters is derived based on the error-square minimization. The stability and convergence conditions of observer and control methods are analyzed using a Lyapunov stability approach. In numerical simulations, the proposed observer and well-known sliding-mode observer are compared for the synchronization of a Lü chaotic system and observer-based stabilization of a Chen chaotic system. The noisy case for synchronization and parameter uncertainty case for stabilization are also considered for both observer-based methods.

  19. Simulation study on heterogeneous variance adjustment for observations with different measurement error variance

    DEFF Research Database (Denmark)

    Pitkänen, Timo; Mäntysaari, Esa A; Nielsen, Ulrik Sander

    2013-01-01

    of variance correction is developed for the same observations. As automated milking systems are becoming more popular the current evaluation model needs to be enhanced to account for the different measurement error variances of observations from automated milking systems. In this simulation study different...... models and different approaches to account for heterogeneous variance when observations have different measurement error variances were investigated. Based on the results we propose to upgrade the currently applied models and to calibrate the heterogeneous variance adjustment method to yield same genetic...

  20. A parameterization of observer-based controllers: Bumpless transfer by covariance interpolation

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Komareji, Mohammad

    2009-01-01

    This paper presents an algorithm to interpolate between two observer-based controllers for a linear multivariable system such that the closed loop system remains stable throughout the interpolation. The method interpolates between the inverse Lyapunov functions for the two original state feedbacks...... and between the Lyapunov functions for the two original observer gains to determine an intermediate observer based controller....

  1. The compression mechanism of garnets based on in situ observations

    Science.gov (United States)

    Dymshits, Anna; Sharygin, Igor; Litasov, Konstantin; Shatskiy, Anton

    2014-05-01

    freedom is minimized and such relations between the XO8 and YO6 sites provide evidence for comparatively more rigid structure. In case of uvarovite the bulk modulus is 162 GPa (Leger et al., 1990), while for Knr we obtain 154 GPa. Such relations between the XO8 and YO6 sites provide evidence for comparatively more rigid structure. As a result, Na-maj with all octahedral sites occupied by silicon has the largest value of the bulk modulus among garnets. It would be interesting to study compressibility of Li-majorite expressed by Yang et al. (2009). That phase has smaller cell volume (1430 Å3) and X-O distance (2.26 Å) but the same YO6 polyhedra fully occupied by silicon. The study was supported by Ministry of Education and Science of Russian Federation, project Nos 14.B25.31.0032, MK-265.2014.5, Russian Foundation for Basic Research No 14-05-00957-a. Hazen, R.M., Downs, R.T., Conrad, P.G., Finger, L.W., Gasparik, T. Comparative compressibilities of majorite-type garnets // Physics and Chemistry of Minerals, 1994, v.21, p.344-349. Leger, J., Redon, A., Chateau, C. Compressions of synthetic pyrope, spessartine and uvarovite garnets up to 25 GPa // Physics and Chemistry of Minerals, 1990, v.17, p.161-167. Milman, V., Akhmatskaya, E., Nobes, R., Winkler, B., Pickard, C., White, J. Systematic ab initio study of the compressibility of silicate garnets // Acta Crystallographica Section B: Structural Science, 2001, v.57, p.163-177. Yang, H., Konzett, J., Frost, D.J., Downs, R.T. X-ray diffraction and Raman spectroscopic study of clinopyroxenes with six-coordinated Si in the Na(Mg0.5Si0.5)Si2O6-NaAlSi2O6 system // American Mineralogist, 2009, v.94, p.942-949.

  2. Detection of Cardiovascular Anomalies: An Observer-Based Approach

    KAUST Repository

    Ledezma, Fernando

    2012-07-01

    In this thesis, a methodology for the detection of anomalies in the cardiovascular system is presented. The cardiovascular system is one of the most fascinating and complex physiological systems. Nowadays, cardiovascular diseases constitute one of the most important causes of mortality in the world. For instance, an estimate of 17.3 million people died in 2008 from cardiovascular diseases. Therefore, many studies have been devoted to modeling the cardiovascular system in order to better understand its behavior and find new reliable diagnosis techniques. The lumped parameter model of the cardiovascular system proposed in [1] is restructured using a hybrid systems approach in order to include a discrete input vector that represents the influence of the mitral and aortic valves in the different phases of the cardiac cycle. Parting from this model, a Taylor expansion around the nominal values of a vector of parameters is conducted. This expansion serves as the foundation for a component fault detection process to detect changes in the physiological parameters of the cardiovascular system which could be associated with cardiovascular anomalies such as atherosclerosis, aneurysm, high blood pressure, etc. An Extended Kalman Filter is used in order to achieve a joint estimation of the state vector and the changes in the considered parameters. Finally, a bank of filters is, as in [2], used in order to detect the appearance of heart valve diseases, particularly stenosis and regurgitation. The first numerical results obtained are presented.

  3. Ground-based Observations of the Solar Sources of Space Weather (Invited Review)

    CERN Document Server

    Veronig, Astrid M

    2016-01-01

    Monitoring of the Sun and its activity is a task of growing importance in the frame of space weather research and awareness. Major space weather disturbances at Earth have their origin in energetic outbursts from the Sun: solar flares, coronal mass ejections and associated solar energetic particles. In this review we discuss the importance and complementarity of ground-based and space-based observations for space weather studies. The main focus is drawn on ground-based observations in the visible range of the spectrum, in particular in the diagnostically manifold H$\\alpha$ spectral line, which enables us to detect and study solar flares, filaments, filament eruptions, and Moreton waves. Existing H$\\alpha$ networks such as the GONG and the Global High-Resolution H$\\alpha$ Network are discussed. As an example of solar observations from space weather research to operations, we present the system of real-time detection of H$\\alpha$ flares and filaments established at Kanzelh\\"ohe Observatory (KSO; Austria) in the...

  4. Comparison of Precipitation Observations from a Prototype Space-based Cloud Radar and Ground-based Radars

    Institute of Scientific and Technical Information of China (English)

    LIU Liping; ZHANG Zhiqiang; YU Danru; YANG Hu; ZHAO Chonghui; ZHONG Lingzhi

    2012-01-01

    A prototype space-based cloud radar has been developed and was installed on an airplane to observe a precipitation system over Tianjin,China in July 2010.Ground-based S-band and Ka-band radars were used to examine the observational capability of the prototype. A cross-comparison algorithm between different wavelengths,spatial resolutions and platform radars is presented.The reflectivity biases,correlation coefficients and standard deviations between the radars are analyzed.The equivalent reflectivity bias between the S- and Ka-band radars were simulated with a given raindrop size distribution.The results indicated that reflectivity bias between the S- and Ka-band radars due to scattering properties was less than 5 dB,and for weak precipitation the bias was negligible. The prototype space-based cloud radar was able to measure a reasonable vertical profile of reflectivity,but the reflectivity below an altitude of 1.5 km above ground level was obscured by ground clutter.The measured reflectivity by the prototype space-based cloud radar was approximately 10.9 dB stronger than that by the S-band Doppler radar (SA radar),and 13.7 dB stronger than that by the ground-based cloud radar.The reflectivity measured by the SA radar was 0.4 dB stronger than that by the ground-based cloud radar.This study could provide a method for the quantitative examination of the observation ability for space-based radars.

  5. Observational attachment theory-based parenting measures predict children's attachment narratives independently from social learning theory-based measures.

    Science.gov (United States)

    Matias, Carla; O'Connor, Thomas G; Futh, Annabel; Scott, Stephen

    2014-01-01

    Conceptually and methodologically distinct models exist for assessing quality of parent-child relationships, but few studies contrast competing models or assess their overlap in predicting developmental outcomes. Using observational methodology, the current study examined the distinctiveness of attachment theory-based and social learning theory-based measures of parenting in predicting two key measures of child adjustment: security of attachment narratives and social acceptance in peer nominations. A total of 113 5-6-year-old children from ethnically diverse families participated. Parent-child relationships were rated using standard paradigms. Measures derived from attachment theory included sensitive responding and mutuality; measures derived from social learning theory included positive attending, directives, and criticism. Child outcomes were independently-rated attachment narrative representations and peer nominations. Results indicated that Attachment theory-based and Social Learning theory-based measures were modestly correlated; nonetheless, parent-child mutuality predicted secure child attachment narratives independently of social learning theory-based measures; in contrast, criticism predicted peer-nominated fighting independently of attachment theory-based measures. In young children, there is some evidence that attachment theory-based measures may be particularly predictive of attachment narratives; however, no single model of measuring parent-child relationships is likely to best predict multiple developmental outcomes. Assessment in research and applied settings may benefit from integration of different theoretical and methodological paradigms.

  6. Complex state variable- and disturbance observer-based current controllers for AC drives

    DEFF Research Database (Denmark)

    Dal, Mehmet; Teodorescu, Remus; Blaabjerg, Frede

    2013-01-01

    , extracted by a disturbance observer and then injected into the current controller. In this study, a revised version of a disturbance observer-based controller and a well known complex variable model-based design with a single set of complex pole are compared in terms of design aspects and performance...... of the parameter and the cross-coupling effect. Moreover, it provides a better performance, smooth and low noisy operation with respect to the complex variable controller....... of the stator current. In order to improve the current control performance an alternative current control strategy was proposed previously aiming to avoid the undesired cross-coupling and non-linearities between the state variables. These effects are assumed as disturbances arisen in the closed-loop path...

  7. Comparison of hydrological simulations of climate change using perturbation of observations and distribution-based scaling

    DEFF Research Database (Denmark)

    Van Roosmalen, Lieke Petronella G; Sonnenborg, Torben; Jensen, Karsten Høgh;

    2011-01-01

    Projected climate change eff ects on groundwater and stream discharges were investigated through simulations with a distributed, physically based, surface water–groundwater model. Input to the hydrological model includes precipitation, reference evapotranspiration, and temperature data...... of the HIRHAM4 regional climate model (RCM). The aim of this study was to determine whether the choice of bias-correction method, applied to the RCM data, aff ected the projected hydrological changes. One method consisted of perturbation of observed data (POD) using climate change signals derived from the RCM...... output, while the other consisted of distribution-based scaling (DBS) of the RCM output. Distributionbased scaling resulted in RCM control period data closely approaching the observed climate data and thereby considerably improved the simulation of recharge and stream discharges. When comparing...

  8. Ozone distributions over southern Lake Michigan: comparisons between ferry-based observations, shoreline-based DOAS observations and air quality forecast models

    Directory of Open Access Journals (Sweden)

    P. A. Cleary

    2014-09-01

    Full Text Available Air quality forecast models typically predict large ozone abundances over water relative to land in the Great Lakes region. While each state bordering Lake Michigan has dedicated monitoring systems, offshore measurements have been sparse, mainly executed through specific short-term campaigns. This study examines ozone abundances over Lake Michigan as measured on the Lake Express ferry, by shoreline Differential Optical Absorption Spectroscopy (DOAS observations in southeastern Wisconsin, and as predicted by the National Air Quality Forecast System. From 2008–2009 measurements of O3, SO2, NO2 and formaldehyde were made in the summertime by DOAS at a shoreline site in Kenosha, WI. From 2008–2010 measurements of ambient ozone conducted on the Lake Express, a high-speed ferry that travels between Milwaukee, WI and Muskegon, MI up to 6 times daily from spring to fall. Ferry ozone observations over Lake Michigan were an average of 3.8 ppb higher than those measured at shoreline in Kenosha with little dependence on position of the ferry or temperature but with highest differences during evening and night. Concurrent ozone forecast images from National Weather System's National Air Quality Forecast System in the upper Midwestern region surrounding Lake Michigan were saved over the ferry ozone sampling period in 2009. The bias of the model O3 forecast was computed and evaluated with respect to ferry-based measurements. The model 1 and 8 h ozone mean biases were both 12 ppb higher than observed ozone, and maximum daily 1 h ozone mean bias was 10 ppb, indicating substantial ozone over-prediction over water. Trends in the bias with respect to location and time of day or month were also explored showing non-uniformity in model bias. Extreme ozone events were predicted by the model but not observed by ferry measurements.

  9. Fatal poisonings in Oslo: a one-year observational study

    Directory of Open Access Journals (Sweden)

    Heyerdahl Fridtjof

    2010-06-01

    Full Text Available Abstract Background Acute poisonings are common and are treated at different levels of the health care system. Since most fatal poisonings occur outside hospital, these must be included when studying characteristics of such deaths. The pattern of toxic agents differs between fatal and non-fatal poisonings. By including all poisoning episodes, cause-fatality rates can be calculated. Methods Fatal and non-fatal acute poisonings in subjects aged ≥16 years in Oslo (428 198 inhabitants were included consecutively in an observational multi-centre study including the ambulance services, the Oslo Emergency Ward (outpatient clinic, and hospitals, as well as medico-legal autopsies from 1st April 2003 to 31st March 2004. Characteristics of fatal poisonings were examined, and a comparison of toxic agents was made between fatal and non-fatal acute poisoning. Results In Oslo, during the one-year period studied, 103 subjects aged ≥16 years died of acute poisoning. The annual mortality rate was 24 per 100 000. The male-female ratio was 2:1, and the mean age was 44 years (range 19-86 years. In 92 cases (89%, death occurred outside hospital. The main toxic agents were opiates or opioids (65% of cases, followed by ethanol (9%, tricyclic anti-depressants (TCAs (4%, benzodiazepines (4%, and zopiclone (4%. Seventy-one (69% were evaluated as accidental deaths and 32 (31% as suicides. In 70% of all cases, and in 34% of suicides, the deceased was classified as drug or alcohol dependent. When compared with the 2981 non-fatal acute poisonings registered during the study period, the case fatality rate was 3% (95% C.I., 0.03-0.04. Methanol, TCAs, and antihistamines had the highest case fatality rates; 33% (95% C.I., 0.008-0.91, 14% (95% C.I., 0.04-0.33, and 10% (95% C.I., 0.02-0.27, respectively. Conclusions Three per cent of all acute poisonings were fatal, and nine out of ten deaths by acute poisonings occurred outside hospital. Two-thirds were evaluated as accidental

  10. Ventilation strategies in burn intensive care: A retrospective observational study

    Directory of Open Access Journals (Sweden)

    Stefano Palazzo

    2014-01-01

    Full Text Available Consensus regarding optimal burns intensive care (BICU patient management is lacking. This study aimed to assess whether ventilation strategies, cardiovascular support and sedation in BICU patients have changed over time, and whether this affects outcome. A retrospective observational study comparing two 12-patient BICU cohorts (2005/06 and 2010/11 was undertaken. Demographic and admission characteristics, ventilation parameters, sedation, fluid resuscitation, cardiovascular support and outcome (length of stay, mortality data were collected from patient notes. Data was analysed using T-tests, Fisher's exact and Mann-Whitney U tests. In our study cohort groups were equivalent in demographic and admission parameters. There were equal ventilator-free days in the two cohorts 10 ± 12.7 vs. 13.3 ± 12.2 ventilator free days; P = 0.447. The 2005/06 cohort were mechanically ventilated more often than in 2010/11 cohort (568 ventilator days/1000 patient BICU days vs. 206 ventilator days/1000 patient BICU days; P = 0.001. The 2005/06 cohort were ventilated less commonly in tracheostomy group/endotracheal tube spontaneous (17.8% vs. 26%; P = 0.001 and volume-controlled modes (34.4% vs. 40.8%; P = 0.001. Patients in 2010/11 cohort were more heavily sedated (P = 0.001 with more long-acting sedative drug use (P = 0.001 than the 2005/06 cohort, fluid administration was equivalent. Patient outcome did not vary. Inhalational injury patients were ventilated in volume-controlled (44.5% vs. 28.1%; P = 0.001 and pressure-controlled modes (18.2% vs. 9.5%; P = 0.001 more frequently than those without. Outcome did not vary. This study showed there has been shift away from mechanical ventilation, with increased use of tracheostomy/tracheal tube airway spontaneous ventilation. Inhalation injury patients require more ventilatory support though patient outcomes do not differ. Prospective trials are required to establish which strategies confer benefit.

  11. A performance weighting procedure for GCMs based on explicit probabilistic models and accounting for observation uncertainty

    Science.gov (United States)

    Renard, Benjamin; Vidal, Jean-Philippe

    2016-04-01

    In recent years, the climate modeling community has put a lot of effort into releasing the outputs of multimodel experiments for use by the wider scientific community. In such experiments, several structurally distinct GCMs are run using the same observed forcings (for the historical period) or the same projected forcings (for the future period). In addition, several members are produced for a single given model structure, by running each GCM with slightly different initial conditions. This multiplicity of GCM outputs offers many opportunities in terms of uncertainty quantification or GCM comparisons. In this presentation, we propose a new procedure to weight GCMs according to their ability to reproduce the observed climate. Such weights can be used to combine the outputs of several models in a way that rewards good-performing models and discards poorly-performing ones. The proposed procedure has the following main properties: 1. It is based on explicit probabilistic models describing the time series produced by the GCMs and the corresponding historical observations, 2. It can use several members whenever available, 3. It accounts for the uncertainty in observations, 4. It assigns a weight to each GCM (all weights summing up to one), 5. It can also assign a weight to the "H0 hypothesis" that all GCMs in the multimodel ensemble are not compatible with observations. The application of the weighting procedure is illustrated with several case studies including synthetic experiments, simple cases where the target GCM output is a simple univariate variable and more realistic cases where the target GCM output is a multivariate and/or a spatial variable. These case studies illustrate the generality of the procedure which can be applied in a wide range of situations, as long as the analyst is prepared to make an explicit probabilistic assumption on the target variable. Moreover, these case studies highlight several interesting properties of the weighting procedure. In

  12. A LEKID-based CMB instrument design for large-scale observations in Greenland

    Science.gov (United States)

    Araujo, D. C.; Ade, P. A. R.; Bond, J. R.; Bradford, K. J.; Chapman, D.; Che, G.; Day, P. K.; Didier, J.; Doyle, S.; Eriksen, H. K.; Flanigan, D.; Groppi, C. E.; Hillbrand, Seth N.; Johnson, B. R.; Jones, G.; Limon, Michele; Miller, A. D.; Mauskopf, P.; McCarrick, H.; Mroczkowski, T.; Reichborn-Kjennerud, B.; Smiley, B.; Sobrin, Joshua; Wehus, I. K.; Zmuidzinas, J.

    2014-08-01

    We present the results of a feasibility study, which examined deployment of a ground-based millimeter-wave polarimeter, tailored for observing the cosmic microwave background (CMB), to Isi Station in Greenland. The instrument for this study is based on lumped-element kinetic inductance detectors (LEKIDs) and an F/2.4 catoptric, crossed-Dragone telescope with a 500 mm aperture. The telescope is mounted inside the receiver and cooled to Linearly polarized signals from the sky are modulated with a metal-mesh half-wave plate that is rotated at the aperture stop of the telescope with a hollow-shaft motor based on a superconducting magnetic bearing. The modular detector array design includes at least 2300 LEKIDs, and it can be configured for spectral bands centered on 150 GHz or greater. Our study considered configurations for observing in spectral bands centered on 150, 210 and 267 GHz. The entire polarimeter is mounted on a commercial precision rotary air bearing, which allows fast azimuth scan speeds with negligible vibration and mechanical wear over time. A slip ring provides power to the instrument, enabling circular scans (360 degrees of continuous rotation). This mount, when combined with sky rotation and the latitude of the observation site, produces a hypotrochoid scan pattern, which yields excellent cross-linking and enables 34% of the sky to be observed using a range of constant elevation scans. This scan pattern and sky coverage combined with the beam size (15 arcmin at 150 GHz) makes the instrument sensitive to 5 < ` < 1000 in the angular power spectra.

  13. OGLE-2015-BLG-0196: Ground-based Gravitational Microlens Parallax Confirmed By Space-Based Observation

    CERN Document Server

    Han, C; Gould, A; Zhu, Wei; Szymański, M K; Soszyński, I; Skowron, J; Mróz, P; Poleski, R; Pietrukowicz, P; Kozłowski, S; Ulaczyk, K; Pawlak, M; Yee, J C; Beichman, C; Novati, S Calchi; Carey, S; Bryden, C; Fausnaugh, M; Gaudi, B S; Henderson, Calen B; Shvartzvald, Y; Wibking, B

    2016-01-01

    In this paper, we present the analysis of the binary gravitational microlensing event OGLE-2015-BLG-0196. The event lasted for almost a year and the light curve exhibited significant deviations from the lensing model based on the rectilinear lens-source relative motion, enabling us to measure the microlens parallax. The ground-based microlens parallax is confirmed by the data obtained from space-based microlens observations using the {\\it Spitzer} telescope. By additionally measuring the angular Einstein radius from the analysis of the resolved caustic crossing, the physical parameters of the lens are determined up to the two-fold degeneracy: $u_00$ solutions caused by the well-known "ecliptic" degeneracy. It is found that the binary lens is composed of two M dwarf stars with similar masses $M_1=0.38\\pm 0.04\\ M_\\odot$ ($0.50\\pm 0.05\\ M_\\odot)$ and $M_2=0.38\\pm 0.04\\ M_\\odot$ ($0.55\\pm 0.06\\ M_\\odot$) and the distance to the lens is $D_{\\rm L}=2.77\\pm 0.23$ kpc ($3.30\\pm 0.29$ kpc). Here the physical parameter...

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

    Science.gov (United States)

    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

  15. Using hypertext and the Internet for structure and management of observational studies.

    Science.gov (United States)

    Carey, V J

    1997-08-15

    The evolution of computer and communications systems in the past decade brings new opportunities for increased efficiency and accuracy of observational studies. In ongoing, large scale research studies, the problem of bridging organizational and analytical methods of the past to modern methods of data structure and control can consume considerable effort. A model for information flow in an observational study is sketched, and the flow is found inherently complex. This complexity and corresponding managerial demands are compounded by database file proliferation and by evolution of system hardware and software. Interactive, network-based database mapping and documentation tools are described as currently implemented in an SAS-based system for the management and analysis of several large epidemiologic studies.

  16. Feedback in formative OSCEs: comparison between direct observation and video-based formats

    Directory of Open Access Journals (Sweden)

    Noëlle Junod Perron

    2016-11-01

    Full Text Available Introduction: Medical students at the Faculty of Medicine, University of Geneva, Switzerland, have the opportunity to practice clinical skills with simulated patients during formative sessions in preparation for clerkships. These sessions are given in two formats: 1 direct observation of an encounter followed by verbal feedback (direct feedback and 2 subsequent review of the videotaped encounter by both student and supervisor (video-based feedback. The aim of the study was to evaluate whether content and process of feedback differed between both formats. Methods: In 2013, all second- and third-year medical students and clinical supervisors involved in formative sessions were asked to take part in the study. A sample of audiotaped feedback sessions involving supervisors who gave feedback in both formats were analyzed (content and process of the feedback using a 21-item feedback scale. Results: Forty-eight audiotaped feedback sessions involving 12 supervisors were analyzed (2 direct and 2 video-based sessions per supervisor. When adjusted for the length of feedback, there were significant differences in terms of content and process between both formats; the number of communication skills and clinical reasoning items addressed were higher in the video-based format (11.29 vs. 7.71, p=0.002 and 3.71 vs. 2.04, p=0.010, respectively. Supervisors engaged students more actively during the video-based sessions than during direct feedback sessions (self-assessment: 4.00 vs. 3.17, p=0.007; active problem-solving: 3.92 vs. 3.42, p=0.009. Students made similar observations and tended to consider that the video feedback was more useful for improving some clinical skills. Conclusion: Video-based feedback facilitates discussion of clinical reasoning, communication, and professionalism issues while at the same time actively engaging students. Different time and conceptual frameworks may explain observed differences. The choice of feedback format should depend on

  17. Feedback in formative OSCEs: comparison between direct observation and video-based formats

    Science.gov (United States)

    Junod Perron, Noëlle; Louis-Simonet, Martine; Cerutti, Bernard; Pfarrwaller, Eva; Sommer, Johanna; Nendaz, Mathieu

    2016-01-01

    Introduction Medical students at the Faculty of Medicine, University of Geneva, Switzerland, have the opportunity to practice clinical skills with simulated patients during formative sessions in preparation for clerkships. These sessions are given in two formats: 1) direct observation of an encounter followed by verbal feedback (direct feedback) and 2) subsequent review of the videotaped encounter by both student and supervisor (video-based feedback). The aim of the study was to evaluate whether content and process of feedback differed between both formats. Methods In 2013, all second- and third-year medical students and clinical supervisors involved in formative sessions were asked to take part in the study. A sample of audiotaped feedback sessions involving supervisors who gave feedback in both formats were analyzed (content and process of the feedback) using a 21-item feedback scale. Results Forty-eight audiotaped feedback sessions involving 12 supervisors were analyzed (2 direct and 2 video-based sessions per supervisor). When adjusted for the length of feedback, there were significant differences in terms of content and process between both formats; the number of communication skills and clinical reasoning items addressed were higher in the video-based format (11.29 vs. 7.71, p=0.002 and 3.71 vs. 2.04, p=0.010, respectively). Supervisors engaged students more actively during the video-based sessions than during direct feedback sessions (self-assessment: 4.00 vs. 3.17, p=0.007; active problem-solving: 3.92 vs. 3.42, p=0.009). Students made similar observations and tended to consider that the video feedback was more useful for improving some clinical skills. Conclusion Video-based feedback facilitates discussion of clinical reasoning, communication, and professionalism issues while at the same time actively engaging students. Different time and conceptual frameworks may explain observed differences. The choice of feedback format should depend on the educational

  18. Assessing the completeness of reporting of observational studies in Colombian Journal of Anesthesiology. Cross sectional study

    NARCIS (Netherlands)

    Bravo-Peña, M. (Mary); Barona-Fong, L. (Luis); Campo-López, J. (Julio); Arroyave, Y. (Yeni); J.A. Calvache (Jose Andres)

    2017-01-01

    textabstractIntroduction The STROBE statement (Strengthening the Reporting of Observational Studies in Epidemiology), consisting of 22 points, was published in 2007 with the aim of improving the reporting of observational research. Objective To determine the completeness of reporting of observationa

  19. Contribution of amateur observations to Saturn storm studies

    CERN Document Server

    Delcroix, Marc

    2010-01-01

    Since 2004, Saturn Electrostatic Discharges (SEDs), which are the radio signatures of lightning in Saturn's atmosphere, have been observed by the Cassini Radio and Plasma Wave Science instrument (RPWS). Despite their important time coverage, these observations lack the resolution and positioning given by imaging around visible wavelengths. Amateur observations from Earth have been increasing in quality and coverage since a few years, bringing information on positions, drift rates and shape evolutions of large visible white spots in Saturn's atmosphere. Combining these two complementary sources has brought better analysis of Saturn's storms evolutions.

  20. A LEKID-based CMB instrument design for large-scale observations in Greenland

    CERN Document Server

    Araujo, D C; Bond, J R; Bradford, K J; Chapman, D; Che, G; Day, P K; Didier, J; Doyle, S; Eriksen, H K; Flanigan, D; Groppi, C E; Hillbrand, S N; Johnson, B R; Jones, G; Limon, M; Miller, A D; Mauskopf, P; McCarrick, H; Mroczkowski, T; Reichborn-Kjennerud, B; Smiley, B; Sobrin, J; Wehus, I K; Zmuidzinas, J

    2014-01-01

    We present the results of a feasibility study, which examined deployment of a ground-based millimeter-wave polarimeter, tailored for observing the cosmic microwave background (CMB), to Isi Station in Greenland. The instrument for this study is based on lumped-element kinetic inductance detectors (LEKIDs) and an F/2.4 catoptric, crossed-Dragone telescope with a 500 mm aperture. The telescope is mounted inside the receiver and cooled to $<\\,4$ K by a closed-cycle $^4$He refrigerator to reduce background loading on the detectors. Linearly polarized signals from the sky are modulated with a metal-mesh half-wave plate that is rotated at the aperture stop of the telescope with a hollow-shaft motor based on a superconducting magnetic bearing. The modular detector array design includes at least 2300 LEKIDs, and it can be configured for spectral bands centered on 150~GHz or greater. Our study considered configurations for observing in spectral bands centered on 150, 210 and 267~GHz. The entire polarimeter is mounte...

  1. Analysis of visibility simulation of three polar regions from lunar-based earth observation

    Science.gov (United States)

    Ye, Hanlin; Liu, Guang; Ren, Yuanzhen; Guo, Huadong; Ding, Yixing

    2016-07-01

    Global environment change has caught the attention of many scientists around the world. The Arctic, Antarctic and Tibet Plateau are known as the three polar regions. They are the world's largest storage of cold and carbon which are the sensitive regions of global environment change. These three regions have significant impacts on the global environment change. It is extremely obvious that the environment change of these three regions is one of the major factors of global environment change. The special geographical positions of these three regions have great influence on the local climate and ecological environment that caused the climate is very bad and few people can get there, so there is very little observation data exists. In addition, these three regions have large scale and long-term observation characteristics. Since the meaning of remote sensing technology came out, we have developed airborne and space-borne Earth observation system. However, when taking three polar regions for researching, we will have to face the problems of temporal coherence and spatial continuity in the global scale, which challenges the Earth observation on the satellite and airborne platform. Moon is the unique natural satellite of the Earth, which always has one side facing it, with the advantages of large coverage, long-life platform, stable geological structure and multi-spheres three-dimensional detecting, turning out to be the ideal platform for observing three polar regions. At present and in the near future, the study of Earth observation data from a lunar observatory would be difficult to carry out, so a simulation is used in this paper to analyze the visibility of three polar regions. At first, we discuss the motion pattern of the Sun-Earth-Moon system. Then we construct a simulation system with simulated optical sensors setting up at different places on the Moon, finding that sunlight has great influence on optical observation. The visible region of a lunar-based optical

  2. Ground-based and spacecraft observations of lightning activity on Saturn

    Science.gov (United States)

    Zakharenko, V.; Mylostna, C.; Konovalenko, A.; Zarka, P.; Fischer, G.; Grießmeier, J.-M.; Litvinenko, G.; Rucker, H.; Sidorchuk, M.; Ryabov, B.; Vavriv, D.; Ryabov, V.; Cecconi, B.; Coffre, A.; Denis, L.; Fabrice, C.; Pallier, L.; Schneider, J.; Kozhyn, R.; Vinogradov, V.; Mukha, D.; Weber, R.; Shevchenko, V.; Nikolaenko, V.

    2012-02-01

    In late 2007, Saturn electrostatic discharges (SED) were simultaneously observed at the radio telescope UTR-2 and with the Cassini spacecraft. Observations at UTR-2 were performed with a multichannel receiver in the frequency range 12-33 MHz, and those performed on Cassini-with a swept frequency receiver that is part of the RPWS (Radio and Plasma Wave Science) instrument in the frequency band 1.8-16 MHz. We got a very good coincidence between data of UTR-2 and Cassini. It is shown for the first time that ground-based radio astronomy lets us detect Saturn's lightning with a high degree of reliability despite terrestrial interferences. This is the necessary basis for further detailed study of the temporal and spectral characteristics of the SEDs with ground based radio telescopes. Based on six observation sessions, several parameters of SEDs were determined, in particularly a correlation of 0.77±0.15 between the average intensity of storms and the e-folding time.

  3. Effects of an Augmented Reality-Based Educational Game on Students' Learning Achievements and Attitudes in Real-World Observations

    Science.gov (United States)

    Hwang, Gwo-Jen; Wu, Po-Han; Chen, Chi-Chang; Tu, Nien-Ting

    2016-01-01

    Augmented reality (AR) has been recognized as a potential technology to help students link what they are observing in the real world to their prior knowledge. One of the most challenging issues of AR-based learning is the provision of effective strategy to help students focus on what they need to observe in the field. In this study, a competitive…

  4. Constellation design for earth observation based on the characteristics of the satellite ground track

    Science.gov (United States)

    Luo, Xin; Wang, Maocai; Dai, Guangming; Song, Zhiming

    2017-04-01

    This paper responds to the increasing need for Earth observation missions and deals with the design of Repeating Sun-Synchronous Constellations (RSSCs) which takes into consideration of constellations composed of one or more orbital planes. Based on the mature design approach of Repeating Sun-synchronous orbits, a novel technique to design RSSCs is presented, which takes the second gravitational zonal harmonic into consideration. In order to obtain regular cycles of observation of the Earth by a single satellite, the orbital relationships have to be satisfied firstly are illustrated. Then, by making full analyses of the characteristics of the satellite ground track, orbital parameters are properly calculated to make other satellites pass on the same or different ground track of the single satellite. Last, single-plane or multi-plane constellations are used to improve the repetitions of the observation and the ground resolution. RSSCs allow observing the same region once at the same local time in a solar day and several times at the different local time in a solar day. Therefore, this kind of constellations meets all requirements for the remote sensing applications, which need to observe the same region under the same or different visible conditions. Through various case studies, the calculation technique is successfully demonstrated.

  5. Prosthetic prescription in the Netherlands: An observational study

    NARCIS (Netherlands)

    Van Der Linde, H.; Geertzen, J.H.B.; Hofstad, C.J.; Van Limbeek, J.; Postema, K.

    2003-01-01

    Prosthetic prescription for lower limb amputees and the methodology used are primarily based on empirical knowledge. Clinical expertise plays an important role that can lead to an adequate prescription; however, a clear evidence based motivation for the choices made cannot be given. This can lead to

  6. Prosthetic prescription in the Netherlands : an observational study

    NARCIS (Netherlands)

    van der Linde, H; Geertzen, JHB; Hofstad, CJ; Postema, K

    2003-01-01

    Prosthetic prescription for lower limb amputees and the methodology used are primarily based on empirical knowledge. Clinical expertise plays an important role that can lead to an adequate prescription; however, a clear evidence based motivation for the choices made cannot be given. This can lead to

  7. Temperature variability during delirium in ICU patients: an observational study.

    Directory of Open Access Journals (Sweden)

    Arendina W van der Kooi

    Full Text Available 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 (β(unadjusted=0.007, 95% confidence interval (CI=0.004 to 0.011, p<0.001. Adjustment for confounders did not alter this result (β(adjusted=0.005, 95% CI=0.002 to 0.008, p<0.001. Delirium was not associated with absolute body temperature (β(unadjusted=-0.03, 95% CI=-0.17 to 0

  8. Temperature-based control of an anaerobic reactor using a multi-model observer-based estimator.

    Science.gov (United States)

    Morel, Emmanuel; Tartakovsky, Boris; Perrier, Michel; Guiot, Serge R

    2007-02-01

    This study presents a temperature-based control strategy for the stabilization of an anaerobic reactor during organic overloads. To prove feasibility of the proposed approach the rate of methane production was followed in batch activity tests and reactor runs during mesophilic-thermophilic transitions. Within the first 0.25-6 h of temperature augmentation, an increase in the rate of methane production was observed with higher rates measured under thermophilic (above 40 degrees C) conditions. However, 24 h after startup both in batch tests and reactor runs, the rate of methane production under thermophilic conditions was inferior to that under optimal mesophilic conditions (35 degrees C). Following these results, a control strategy based on short-term augmentation of the reactor temperature was proposed and tested in a 10 L UASB reactor. The control strategy employed a multi-model observer-based estimator to stabilize the effluent COD concentration during organic overloads. The temperature-based control resulted in an increased methanization rate and improved reactor stability overall.

  9. Synergy of multifrequency studies from observations of NGC6334I

    CERN Document Server

    Seifahrt, Andreas; Beuther, Henrik; Leurini, Silvia; Brogan, Crystal L; Hunter, Todd R; Menten, Karl M; Stecklum, Bringfried; 10.1088/1742-6596/131/1/012030

    2008-01-01

    We combine multifrequency observations from the millimeter to near infrared wavelengths that demonstrate the spatial distributions of H2, CO, and NH3 emission, which are all manifestations of various shocks driven by outflows of deeply embedded sources in NGC6334I. In addition to the well-known northeast-southwest outflow we detect at least one more outflow in the region by combining observations from APEX, ATCA, SMA, Spitzer and VLT/ISAAC. Potential driving sources will be discussed. NGC6334I exhibits several signs of active star formation and will be a major target for future observatories such as Herschel and ALMA.

  10. Multi-scale Drivers of Variations in Atmospheric Evaporative Demand Based on Observations and Physically-based Modeling

    Science.gov (United States)

    Peng, L.; Sheffield, J.; Li, D.

    2015-12-01

    Evapotranspiration (ET) is a key link between the availability of water resources and climate change and climate variability. Variability of ET has important environmental and socioeconomic implications for managing hydrological hazards, food and energy production. Although there have been many observational and modeling studies of ET, how ET has varied and the drivers of the variations at different temporal scales remain elusive. Much of the uncertainty comes from the atmospheric evaporative demand (AED), which is the combined effect of radiative and aerodynamic controls. The inconsistencies among modeled AED estimates and the limited observational data may originate from multiple sources including the limited time span and uncertainties in the data. To fully investigate and untangle the intertwined drivers of AED, we present a spectrum analysis to identify key controls of AED across multiple temporal scales. We use long-term records of observed pan evaporation for 1961-2006 from 317 weather stations across China and physically-based model estimates of potential evapotranspiration (PET). The model estimates are based on surface meteorology and radiation derived from reanalysis, satellite retrievals and station data. Our analyses show that temperature plays a dominant role in regulating variability of AED at the inter-annual scale. At the monthly and seasonal scales, the primary control of AED shifts from radiation in humid regions to humidity in dry regions. Unlike many studies focusing on the spatial pattern of ET drivers based on a traditional supply and demand framework, this study underlines the importance of temporal scales when discussing controls of ET variations.

  11. A study on diffuse source detection by HXMT scanning observation

    CERN Document Server

    Guan, Ju; Wu, Mei; Song, Li-Ming; Huo, Zhuo-Xi

    2015-01-01

    The Hard X-ray Modulation Telescope (HXMT) is a collimated scan X-ray satellite mainly devoted to a sensitive all-sky survey and pointed observations in 1-250 keV. We expect various diffuse sources to be detected in its scanning observations due to the large rigidity factor of the telescope. Diffuse source detection performance of HXMT scanning observation depends not only on the instrument but also on its data analysis method since images have to be reconstructed from HXMT observed data. In this paper, we introduce a multiscale maximum entropy (MSME) algorithm for HXMT image restoration and propose an improved method, ensemble multiscale maximum entropy (EMSME) method, to alleviate the problem of mode mixing exiting in MSME. Simulation have been performed on the detection of the diffuse source Cen A by HXMT in the all-sky survey mode. The results show that the MSME method is adapted to the deconvolution task of HXMT for diffuse source detection and the improved method could suppress noise and improve the cor...

  12. Water and sodium intake habits and status of ultra-endurance runners during a multi-stage ultra-marathon conducted in a hot ambient environment: an observational field based study

    Science.gov (United States)

    2013-01-01

    , irrespective of running speed and gender. Normonatraemia was observed in the majority of ultra-runners throughout MSUM, despite sodium ingestion under benchmark recommendations. PMID:23320854

  13. Water and sodium intake habits and status of ultra-endurance runners during a multi-stage ultra-marathon conducted in a hot ambient environment: an observational field based study

    Directory of Open Access Journals (Sweden)

    Costa Ricardo JS

    2013-01-01

    Full Text Available Abstract Background Anecdotal evidence suggests ultra-runners may not be consuming sufficient water through foods and fluids to maintenance euhydration, and present sub-optimal sodium intakes, throughout multi-stage ultra-marathon (MSUM competitions in the heat. Subsequently, the aims were primarily to assess water and sodium intake habits of recreational ultra-runners during a five stage 225 km semi self-sufficient MSUM conducted in a hot ambient environment (Tmax range: 32°C to 40°C; simultaneously to monitor serum sodium concentration, and hydration status using multiple hydration assessment techniques. Methods Total daily, pre-stage, during running, and post-stage water and sodium ingestion of ultra-endurance runners (UER, n = 74 and control (CON, n = 12 through foods and fluids were recorded on Stages 1 to 4 by trained dietetic researchers using dietary recall interview technique, and analysed through dietary analysis software. Body mass (BM, hydration status, and serum sodium concentration were determined pre- and post-Stages 1 to 5. Results Water (overall mean (SD: total daily 7.7 (1.5 L/day, during running 732 (183 ml/h and sodium (total daily 3.9 (1.3 g/day, during running 270 (151 mg/L ingestion did not differ between stages in UER (p vs. CON. Exercise-induced BM loss was 2.4 (1.2% (p p > 0.05 vs. CON pre-stage. Asymptomatic hyponatraemia (n = 8 UER, corresponding to 42% of sampled participants. Pre- and post-stage urine colour, urine osmolality and urine/plasma osmolality ratio increased (p p  Conclusion Water intake habits of ultra-runners during MSUM conducted in hot ambient conditions appear to be sufficient to maintain baseline euhydration levels. However, fluid over-consumption behaviours were evident along competition, irrespective of running speed and gender. Normonatraemia was observed in the majority of ultra-runners throughout MSUM, despite sodium ingestion under benchmark recommendations.

  14. A preliminary study for spatial representiveness of flux observation at ChinaFLUX sites

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    <正>The results of eddy covariance observation system could represent the physical process at certain area of the surface. Thus point-to-area representativeness was of primary interest in flux observation. This research presents a preliminary study for flux observation at ChinaFLUX sites by the use of observation data and Flux Source Area Model (FSAM). Results show that the footprint expands and is further away from flux tower when atmosphere becomes more stable, the observation height increases, or the surfaces become smoother. This suggests that the area represented by the flux observation becomes larger. The distances from the reference point to the maximum point Smax and the minimum point x1 of source weight function (Dmax and Dmin, respectively) can be influenced by atmosphere stability which becomes longer when atmosphere is more stable. For more rough surfaces and lower observation point Dmax and Dmin become shorter. This research gives the footprint at level P=90% at ChinaFLUX sites at different atmosphere stability. The preliminary results of spatial representiveness at ChinaFLUX sites were given based on the dominant wind direction and footprint response to various factors. The study also provides some theoretical basis for data quality control and evaluating data uncertainty.

  15. 基于互联网的感视知觉学习治疗弱视的疗效观察%Based on the internet perception study treatment of amblyopia clinical observation

    Institute of Scientific and Technical Information of China (English)

    吴志兵; 徐峻; 吴军

    2012-01-01

    Objective To evaluate the efficacy of Mental Imagery Perceptual Learning System for the treatment of amblyopia. Methods 197 children(317 eyes) with amblyopia were recruited. Spectacles were prescribed based on atro-pine ointment cycloplegic refraction. Patients were assigned to receive either occlusion therapy or " Mental Imagery" perceptual learning according to their best corrected acuity . The following indices were analyzed : type of amblyopia , depth of amblyopia, age and treatment efficiency. Results With patients who received average 4 months "Mental Imagery" perceptual learning , amblyopia cured in 77% and improved in 30. 28% . The gross treatment efficiency was 88. 96% . Conclusion Mental Imagery Perceptual Learning System is an effective way for treating amblyopia .%目的 评价"脑力影像"感视知觉学习系统在弱视治疗中的效果.方法 对197例(317只眼)弱视儿童阿托品眼膏散瞳验光配镜,并根据矫正视力情况,给予相应的遮盖,利用"脑力影像"感知觉学习系统进行弱视治疗,对以下指标进行分析:弱视的类型、弱视的程度、患者的年龄与治疗效果.结果 平均接受4个月弱视治疗,总有效率88.96%,其中基本治愈58.67%,有进步30.28%.结论 "脑力影像"感知觉学习系统治疗弱视是一种有效的方法.

  16. Trends of Do-Not-Resuscitate consent and hospice care utilization among noncancer decedents in a tertiary hospital in Taiwan between 2010 and 2014: A Hospital-based observational study.

    Science.gov (United States)

    Chang, Hsiao-Ting; Lin, Ming-Hwai; Chen, Chun-Ku; Chou, Pesus; Chen, Tzeng-Ji; Hwang, Shinn-Jang

    2016-11-01

    Do-Not-Resuscitate (DNR) and hospice care are not only applied to cancer patients but also to patients with noncancer progressive illness. However, the trends of DNR consent and hospice utilization are not well explored for noncancer patients. This study aimed to explore the trends of DNR consent and hospice care utilization among noncancer decedents in a tertiary hospital in Taiwan. We analyzed the Death and Hospice Palliative Care Database from the Taipei Veterans General Hospital in Taiwan. The Death and Hospice Palliative Care Database contains information including patient sex, major diagnosis, admission date, date of death, age at death, department at discharge, status of DNR consent, and status of hospice care of patients who died in the Taipei Veterans General Hospital. Data on patients aged 20 years old or more who died of major terminal noncancer diseases, including brain diseases, amyotrophic lateral sclerosis, dementia, chronic obstructive pulmonary disease (COPD) and other lung diseases, heart failure, chronic liver diseases and cirrhosis, and renal failure between 2010 and 2014 were extracted for analysis. A total of 1416 patients aged 20 years or more died of major noncancer diseases in Taipei Veterans General Hospital during the study period. The most common diagnosis was brain diseases, amyotrophic lateral sclerosis, and dementias (n = 510, 36%) followed by chronic obstructive pulmonary disease and other lung diseases (n = 322, 22.7%). Among these noncancer decedents, 1045 (73.8%) had DNR consents, while 134 (9.5%) received hospice care. Patients diagnosed with renal failure had the highest percentage of DNR consent (80%), followed by chronic liver diseases and cirrhosis (77.7%). Patients diagnosed with chronic liver diseases and cirrhosis had the highest percentage of hospice utilization (17.4%), followed by renal failure (15.8%). The percentages of DNR consent and hospice utilization were significantly different across different disease

  17. Geology Structure Identification based on Polarimetric SAR (PolSAR) Data and Field Based Observation at Ciwidey Geothermal Field

    Science.gov (United States)

    Pradipta, R. A.; Saepuloh, A.; Suryantini

    2016-09-01

    Geological structure observation is difficult to be conducted at Quaternary volcanic field due to the classical problem at tropical region such as intensive erosion, dense vegetation covers, and rough terrain. The problem hampers the field observation especially for geological structures mapping. In order to overcome the problems, an active remote sensing technology based on Polarimetric Synthetic Aperture Radar (PolSAR) data was used in this study. The longer wavelength of microwave than optical region caused the SAR layer penetration higher than optics. The Ciwidey Geothermal Field, Indonesia was selected as study area because of the existence of surface manifestations with lack information about the control of geological structures to the geothermal system. Visual interpretation based on composite polarization modes was applied to identify geological structures at study area. The color composite Red-Green-Blue for HV-HH-VV polarizations provided highest texture and structural features among the other composite combination. The Linear Features Density (LFD) map was also used to interpret the fractures zones. The calculated LFD showed high anomaly about 3.6 km/km2 with two strike directions NW-SE and NE-SW. Interestingly, the surface geothermal manifestation agreed with the low anomaly of LFD. The geological structures consisted of ten faults were successfully detected and mapped. The faults type mainly are oblique-slip with strike directions NE-SW and NW-SE.

  18. A Mechanical Study of a Glass Fabric-Thermoplastic Resin Composite: 3D-DIC and X-ray tomographic observations explained by numerical simulations based on a spectral solver

    CERN Document Server

    Boufaida, Zakariya; André, Stéphane; Farge, Laurent

    2016-01-01

    In the study presented in this paper, we analyzed the mechanical response of a glass fiber plain weave/polymer composite at the fabric millimetric mesoscale. The detail of the stress and strain fields in a fabric repeating unit cell was numerically calculated using CraFT (Composite response and Fourier Transforms), a code specifically conceived for simulating the mechanical behaviour of materials with complex microstructure. The local strain fields obtained by simulation were found to be in very good agreement with measurements carried out using 3D Digital Image Correlation (3D DIC). From numerical stress fields calculated with the CraFT solver, we also highlighted the subregions inside the periodic mesostructure where there is maximum stress. Furthermore, with X-ray tomography post mortem measurements, we were able to confirm that certain damage modes were well initiated in these microstructure subregions of stress concentration.

  19. Accounting for correlated observations in an age-based state-space stock assessment model

    DEFF Research Database (Denmark)

    Berg, Casper Willestofte; Nielsen, Anders

    2016-01-01

    Fish stock assessment models often relyon size- or age-specific observations that are assumed to be statistically independent of each other. In reality, these observations are not raw observations, but rather they are estimates from a catch-standardization model or similar summary statistics based...

  20. Non-fragile observer-based passive control for descriptor systems with time-delay

    Institute of Scientific and Technical Information of China (English)

    QinLI; Qingling ZHANG; Jichun WANG

    2009-01-01

    This paper investigates the problem of non-fragile observer-based passive control for descriptor systems with time-delay.The perturbations in both the control gain and observer gain of the observer-based controller are considered.For the cases of the additive perturbations and multiplicative perturbations,sufficient conditions are given such that the closed-loop systems are admissible and passive with dissipation 77.The observer-based controller gains could be obtained from the solutions of linear matrix inequalities (LMIs).Moreover,the maximum dissipation of the system is provided.Simulation examples are given to show the effectiveness of the deign methods.

  1. Ground-Based Network and Supersite Observations to Complement and Enrich EOS Research

    Science.gov (United States)

    Tsay, Si-Chee; Holben, Brent N.; Welton, Ellsworth J.

    2011-01-01

    Since 1997 NASA has been successfully launching a series of satellites - the Earth Observing System (EOS) - to intensively study, and gain a better understanding of, the Earth as an integrated system. Space-borne remote sensing observations, however, are often plagued by contamination of surface signatures. Thus, ground-based in-situ and remote-sensing measurements, where signals come directly from atmospheric constituents, the sun, and/or the Earth-atmosphere interactions, provide additional information content for comparisons that confirm quantitatively the usefulness of the integrated surface, aircraft, and satellite datasets. Through numerous participations, particularly but not limited to the EOS remote-sensing/retrieval and validation projects over the years, NASA/GSFC has developed and continuously refined ground-based networks and mobile observatories that proved to be vital in providing high temporal measurements, which complement and enrich the satellite observations. These are: the AERO NET (AErosol RObotic NETwork) a federation of ground-based globally distributed network of spectral sun-sky photometers; the MPLNET (Micro-Pulse Lidar NETwork, a similarly organized network of micro-pulse lidar systems measuring aerosol and cloud vertical structure continuously; and the SMART-COMMIT (Surface-sensing Measurements for Atmospheric Radiative Transfer - Chemical, Optical & Microphysical Measurements of In-situ Troposphere, mobile observatories, a suite of spectral radiometers and in-situ probes acquiring supersite measurements. Most MPLNET sites are collocated with those of AERONET, and both networks always support the deployment of SMART-COMMIT worldwide. These data products follow the data structure of EOS conventions: Level-0, instrument archived raw data; Level-1 (or 1.5), real-time data with no (or limited) quality assurance; Level-2, not real high temporal and spectral resolutions. In this talk, we will present NASA/GSFC groundbased facilities, serving

  2. Subtropical and Polar Cirrus Clouds Characterized by Ground-Based Lidars and CALIPSO/CALIOP Observations

    Science.gov (United States)

    Córdoba-Jabonero, Carmen; Lopes, Fabio J. S.; Landulfo, Eduardo; Ochoa, Héctor; Gil-Ojeda, Manuel

    2016-06-01

    Cirrus clouds are product of weather processes, and then their occurrence and macrophysical/optical properties can vary significantly over different regions of the world. Lidars can provide height-resolved measurements with a relatively good both vertical and temporal resolutions, making them the most suitable instrumentation for high-cloud observations. The aim of this work is to show the potential of lidar observations on Cirrus clouds detection in combination with a recently proposed methodology to retrieve the Cirrus clouds macrophysical and optical features. In this sense, a few case studies of cirrus clouds observed at both subtropical and polar latitudes are examined and compared to CALIPSO/CALIOP observations. Lidar measurements are carried out in two stations: the Metropolitan city of Sao Paulo (MSP, Brazil, 23.3°S 46.4°W), located at subtropical latitudes, and the Belgrano II base (BEL, Argentina, 78ºS 35ºW) in the Antarctic continent. Optical (COD-cloud optical depth and LR-Lidar Ratio) and macrophysical (top/base heights and thickness) properties of both the subtropical and polar cirrus clouds are reported. In general, subtropical Cirrus clouds present lower LR values and are found at higher altitudes than those detected at polar latitudes. In general, Cirrus clouds are detected at similar altitudes by CALIOP. However, a poor agreement is achieved in the LR retrieved between ground-based lidars and space-borne CALIOP measurements, likely due to the use of a fixed (or low-variable) LR value in CALIOP inversion procedures.

  3. Subtropical and Polar Cirrus Clouds Characterized by Ground-Based Lidars and CALIPSO/CALIOP Observations

    Directory of Open Access Journals (Sweden)

    Córdoba-Jabonero Carmen

    2016-01-01

    Full Text Available Cirrus clouds are product of weather processes, and then their occurrence and macrophysical/optical properties can vary significantly over different regions of the world. Lidars can provide height-resolved measurements with a relatively good both vertical and temporal resolutions, making them the most suitable instrumentation for high-cloud observations. The aim of this work is to show the potential of lidar observations on Cirrus clouds detection in combination with a recently proposed methodology to retrieve the Cirrus clouds macrophysical and optical features. In this sense, a few case studies of cirrus clouds observed at both subtropical and polar latitudes are examined and compared to CALIPSO/CALIOP observations. Lidar measurements are carried out in two stations: the Metropolitan city of Sao Paulo (MSP, Brazil, 23.3°S 46.4°W, located at subtropical latitudes, and the Belgrano II base (BEL, Argentina, 78ºS 35ºW in the Antarctic continent. Optical (COD-cloud optical depth and LR-Lidar Ratio and macrophysical (top/base heights and thickness properties of both the subtropical and polar cirrus clouds are reported. In general, subtropical Cirrus clouds present lower LR values and are found at higher altitudes than those detected at polar latitudes. In general, Cirrus clouds are detected at similar altitudes by CALIOP. However, a poor agreement is achieved in the LR retrieved between ground-based lidars and space-borne CALIOP measurements, likely due to the use of a fixed (or low-variable LR value in CALIOP inversion procedures.

  4. Estimation of the neuronal activation using fMRI data: An observer-based approach

    KAUST Repository

    Laleg-Kirati, Taous-Meriem

    2013-06-01

    This paper deals with the estimation of the neuronal activation and some unmeasured physiological information using the Blood Oxygenation Level Dependent (BOLD) signal measured using functional Magnetic Resonance Imaging (fMRI). We propose to use an observer-based approach applied to the balloon hemodynamic model. The latter describes the relation between the neural activity and the BOLD signal. The balloon model can be expressed in a nonlinear state-space representation where the states, the parameters and the input (neuronal activation), are unknown. This study focuses only on the estimation of the hidden states and the neuronal activation. The model is first linearized around the equilibrium and an observer is applied to this linearized version. Numerical results performed on synthetic data are presented.

  5. Observational study of compliance with Queensland bicycle helmet laws.

    Science.gov (United States)

    Debnath, Ashim Kumar; Haworth, Narelle; Schramm, Amy; Williamson, Amy

    2016-12-01

    Mandatory bicycle helmet laws have been found to increase helmet wearing rates in Australia and internationally. However, much of the research on factors influencing compliance with the Australian helmet laws is dated or focuses on commuters and city areas only. To address this gap, video recordings of bicycle riders were undertaken at 17 sites across Queensland, Australia, representing a mixture of on- and off-road locations, speed limits and regions. Helmet status was able to be determined for 98% of riders observed. The level of compliance with the laws was very high, with 98.3% of the more than 27,000 riders observed wearing helmets. Riders riding on roads were less compliant than those riding on bicycle paths, but no significant differences were observed between the school-holiday and school-term periods. Among the on-road riders, boys were less compliant than girls and overall children were less compliant than adults. Higher compliance levels were found for group riders, road bike riders, lycra-clad riders, during morning hours, and on 50km/h or lower speed limit roads. While the overall level of compliance was very high, certain subgroups were identified as a possible focus for interventions to further improve the compliance level, for example children (particularly boys) riding mountain bikes away from groups during the afternoon hours on 60km/h roads.

  6. Heavy precipitation retrieval from combined satellite observations and ground-based lightning measurements

    Science.gov (United States)

    Mugnai, A.; Dietrich, S.; Casella, D.; di Paola, F.; Formenton, M.; Sanò, P.

    2010-09-01

    We have developed a series of algorithms for the retrieval of precipitation (especially, heavy precipitation) over the Mediterranean area using satellite observations from the available microwave (MW) radiometers onboard low Earth orbit (LEO) satellites and from the visible-infrared (VIS-IR) SEVIRI radiometer onboard the European geosynchronous (GEO) satellite Meteosat Second Generation (MSG), in conjunction with lightning data from ground-based networks - such as ZEUS and LINET. These are: • A new approach for precipitation retrieval from space (which we call the Cloud Dynamics and Radiation Database approach, CDRD) that incorporates lightning and environmental/dynamical information in addition to the upwelling microwave brightness temperatures (TB’s) so as to reduce the retrieval uncertainty and improve the retrieval performance; • A new combined MW-IR technique for producing frequent precipitation retrievals from space (which we call PM-GCD technique), that uses passive-microwave (PM) retrievals in conjunction with lightning information and the Global Convection Detection (GCD) technique to discriminate deep convective clouds within the GEO observations; • A new morphing approach (which we call the Lightning-based Precipitation Evolving Technique, L-PET) that uses the available lightning measurements for propagating the rainfall estimates from satellite-borne MW radiometers to a much higher time resolution than the MW observations. We will present and discuss our combined MW/IR/lightning precipitation algorithms and analyses with special reference to some case studies over the western Mediterranean.

  7. Direct radiative effect of aerosols based on PARASOL and OMI satellite observations

    Science.gov (United States)

    Lacagnina, Carlo; Hasekamp, Otto P.; Torres, Omar

    2017-02-01

    Accurate portrayal of the aerosol characteristics is crucial to determine aerosol contribution to the Earth's radiation budget. We employ novel satellite retrievals to make a new measurement-based estimate of the shortwave direct radiative effect of aerosols (DREA), both over land and ocean. Global satellite measurements of aerosol optical depth, single-scattering albedo (SSA), and phase function from PARASOL (Polarization and Anisotropy of Reflectances for Atmospheric Sciences coupled with Observations from a Lidar) are used in synergy with OMI (Ozone Monitoring Instrument) SSA. Aerosol information is combined with land-surface bidirectional reflectance distribution function and cloud characteristics from MODIS (Moderate Resolution Imaging Spectroradiometer) satellite products. Eventual gaps in observations are filled with the state-of-the-art global aerosol model ECHAM5-HAM2. It is found that our estimate of DREA is largely insensitive to model choice. Radiative transfer calculations show that DREA at top-of-atmosphere is -4.6 ± 1.5 W/m2 for cloud-free and -2.1 ± 0.7 W/m2 for all-sky conditions, during year 2006. These fluxes are consistent with, albeit generally less negative over ocean than, former assessments. Unlike previous studies, our estimate is constrained by retrievals of global coverage SSA, which may justify different DREA values. Remarkable consistency is found in comparison with DREA based on CERES (Clouds and the Earth's Radiant Energy System) and MODIS observations.

  8. Direct Radiative Effect of Aerosols Based on PARASOL and OMI Satellite Observations

    Science.gov (United States)

    Lacagnina, Carlo; Hasekamp, Otto P.; Torres, Omar

    2017-01-01

    Accurate portrayal of the aerosol characteristics is crucial to determine aerosol contribution to the Earth's radiation budget. We employ novel satellite retrievals to make a new measurement-based estimate of the shortwave direct radiative effect of aerosols (DREA), both over land and ocean. Global satellite measurements of aerosol optical depth, single-scattering albedo (SSA), and phase function from PARASOL (Polarization and Anisotropy of Reflectances for Atmospheric Sciences coupled with Observations from a Lidar) are used in synergy with OMI (Ozone Monitoring Instrument) SSA. Aerosol information is combined with land-surface bidirectional reflectance distribution function and cloud characteristics from MODIS (Moderate Resolution Imaging Spectroradiometer) satellite products. Eventual gaps in observations are filled with the state-of-the-art global aerosol model ECHAM5-HAM2. It is found that our estimate of DREA is largely insensitive to model choice. Radiative transfer calculations show that DREA at top-of-atmosphere is -4.6 +/- 1.5 W/sq m for cloud-free and -2.1 +/- 0.7 W/sq m for all-sky conditions, during year 2006. These fluxes are consistent with, albeit generally less negative over ocean than, former assessments. Unlike previous studies, our estimate is constrained by retrievals of global coverage SSA, which may justify different DREA values. Remarkable consistency is found in comparison with DREA based on CERES (Clouds and the Earth's Radiant Energy System) and MODIS observations.

  9. Space-based visible observation strategy for beyond-LEO objects based on an equatorial LEO satellite with multi-sensors

    Science.gov (United States)

    Hu, Yun-peng; Huang, Jian-yu; Chen, Lei

    2017-04-01

    Many space-based visible observation strategies based on Low Earth Orbit (LEO) satellites for observing Geosynchronous Orbit (GEO) objects were proposed previously. However, there were few studies about other beyond-LEO objects (Geostationary Transfer Orbit (GTO) objects, Medium Earth Orbit (MEO) objects, and Molniya objects). In this paper, a space-based visible observation strategy is proposed for observing GEO objects, GTO objects, MEO objects (especially global navigation satellites), and Molniya objects simultaneously to get more orbital data, using an earth-oriented equatorial LEO satellite with three sensors. This work is focused on the pointing geometry. Brightness of observed objects and sensitivity of sensors are assumed under the relative ideal conditions. First, the distribution characteristics of these beyond-LEO objects are discussed. And in order to observe global navigation satellites efficiently, joint regions formed by the track superposition of two adjacent orbits in a constellation are proposed. To offset the influence of the earth shadow and constraint of sun-target-observer angle, two sensors pointing inside of the equatorial plane are used to observe GEO and GTO objects. The installation angle of the third sensor is optimized to obtain a relative high coverage rate for observing global navigation satellites and Molniya objects based on joint regions. Finally, the coverage rate, the number of observations, and observation duration under different sensors with different field of views (FOVs) are compared and analyzed respectively.

  10. Posterior muscle chain activity during various extension exercises: an observational study

    OpenAIRE

    De Ridder, Eline MD; Oosterwijck, Jessica O; Vleeming, Andry; Vanderstraeten, Guy G.; Danneels, Lieven A

    2013-01-01

    Background: Back extension exercises are often used in the rehabilitation of low back pain. However, at present it is not clear how the posterior muscles are recruited during different types of extension exercises. Therefore, the present study will evaluate the myoelectric activity of thoracic, lumbar and hip extensor muscles during different extension exercises in healthy persons. Based on these physiological observations we will make recommendations regarding the use of extensions exercises...

  11. The Performance and Feasibility of Ensemble Forecast Sensitivity to Observations-based Proactive Quality Control Scheme

    Science.gov (United States)

    Chen, T. C.; Hotta, D.; Kalnay, E.

    2015-12-01

    Operational numerical weather prediction (NWP) systems occasionally exhibit "forecast skill dropouts" in which the forecast skill drops to an abnormally low level, due in part to the assimilation of flawed observational data. Recent studies have shown that a diagnostic technique called Ensemble Forecast Sensitivity to Observations (EFSO) can detect such observations (Kalnay et.al 2012; Ota et al. 2013, Tellus A). Based on this technique, a new Quality Control (QC) scheme called Proactive QC (PQC) has been proposed which detects "flawed" observations using EFSO after just 6 hours forecast, when the analysis at the next cycle becomes available for verification and then repeats the analysis and forecast without using the detected observations (Hotta 2014). In Hotta (2014), it was shown using the JCSDA S4 Testbed that the 6hr PQC reduces the 24-hour forecast errors from the detected skill dropout events. With such encouraging results we are performing preliminary experiments towards operational implementation. First, we show that offline PQC correction can significantly reduce forecast errors up to 5 days, and that the reduction and improved areal coverage can grow with synoptic weather disturbances for several days. Second, with online PQC cycle experiment the reduction of forecast error is shown to be even larger than in the offline version, since the effect could accumulate over each time we perform a PQC correction. Finally, the operational center imposes very tight schedule in order to deliver the products on time, thus the computational cost has to be minimized in order for PQC to be implemented. To avoid performing the analysis twice, which is the most expensive part of PQC, we test the accuracy of constant-K approximation, which assumes the Kalman gain K doesn't change much given the fact that only a small subset of observation is rejected. In this presentation, we will demonstrate the performance and feasibility of PQC implementation in real-time operational

  12. A Training Study of the Hercules Observer Trainer

    Science.gov (United States)

    2009-04-01

    des tâches et des exigences en matière de formation, et a déterminé une solution technique qui a été mise en œuvre dans toute une gamme de contrats ...CAE Professional Services Inc. Call-up 7949-08 under Standing Offer W7711-057949. April 2007 – March 2008. [7] Hercules Observer Trainer System...Development. CAE Professional Services Inc. Call-up 7949-06 under Standing Offer W7711-057949. December 2006 – March 2007. [8] High Performance Visual

  13. Temporal sequence in observational studies to establish causality

    Directory of Open Access Journals (Sweden)

    Luis Carlos Silva Ayçaguer, PhD

    2014-05-01

    Full Text Available 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.

  14. Astronomical Observations Astronomy and the Study of Deep Space

    CERN Document Server

    2010-01-01

    Our Search for knowledge about the universe has been remarkable, heartbreaking, fantastical, and inspiring, and this search is just beginning. Astronomical Observations is part of a 7 book series that takes readers through a virtual time warp of our discovery. From the nascent space programs of the 1960's to today's space tourism and the promise of distant planet colonization, readers will be transfixed. Throughout this journey of the mind, Earth-bound explorers gain keen insight into the celestial phenomena that have fascinated humans for centuries. Thrilling narratives about indefatigable sc

  15. Optimal Observability Analysis of Gimbled Inertial Navigation System on the Moving Base

    Institute of Scientific and Technical Information of China (English)

    于家城; 陈家斌

    2004-01-01

    To investigate the observability of gimbled inertial navigation system when the base moves on the basis of piece-wise constant system's observability theory and singular value decomposition, the variation of the singular value in the observability matrix with time is discussed. The simulation results reveal that only if orientation angle is 60° and the flight route is S-figure in initial alignment, the optimal observability is obtained, thus a theoretical foundation for fast and accurate alignment of GINS is provided.

  16. HIRDLS observations of global gravity wave absolute momentum fluxes: A wavelet based approach

    Science.gov (United States)

    John, Sherine Rachel; Kishore Kumar, Karanam

    2016-02-01

    Using wavelet technique for detection of height varying vertical and horizontal wavelengths of gravity waves, the absolute values of gravity wave momentum fluxes are estimated from High Resolution Dynamics Limb Sounder (HIRDLS) temperature measurements. Two years of temperature measurements (2005 December-2007 November) from HIRDLS onboard EOS-Aura satellite over the globe are used for this purpose. The least square fitting method is employed to extract the 0-6 zonal wavenumber planetary wave amplitudes, which are removed from the instantaneous temperature profiles to extract gravity wave fields. The vertical and horizontal wavelengths of the prominent waves are computed using wavelet and cross correlation techniques respectively. The absolute momentum fluxes are then estimated using prominent gravity wave perturbations and their vertical and horizontal wavelengths. The momentum fluxes obtained from HIRDLS are compared with the fluxes obtained from ground based Rayleigh LIDAR observations over a low latitude station, Gadanki (13.5°N, 79.2°E) and are found to be in good agreement. After validation, the absolute gravity wave momentum fluxes over the entire globe are estimated. It is found that the winter hemisphere has the maximum momentum flux magnitudes over the high latitudes with a secondary maximum over the summer hemispheric low-latitudes. The significance of the present study lies in introducing the wavelet technique for estimating the height varying vertical and horizontal wavelengths of gravity waves and validating space based momentum flux estimations using ground based lidar observations.

  17. Observational study of daytime ionospheric irregularities associated with typhoon

    Institute of Scientific and Technical Information of China (English)

    XIAO SaiGuan; SHI JianKui; ZHANG DongHe; HAO YongQiang; HUANG WeiQuan

    2012-01-01

    Spread-F is a manifestation of ionospheric irregularities and generally takes place at nighttime.However,it can also be observed seldom at daytime.It is recognized that acoustic gravity waves (AGWs) play an important role in triggering plasma instability which results in spread-F in the ionosphere.The typhoon is a main source of the AGWs.In this paper,two cases of ionospheric daytime spread-F in the period of typhoon were analyzed.One case was on July 29,1988 and the other was on August 01,1989.The results showed the following:1) There were some wave-like disturbances appearing in the HF Doppler records firstly,consequently the Doppler echo traces became scattered,which indicated that the ionospheric spread-F was triggered; 2) the blurred echo traces in the both two cases appeared in the morning (08:30-11:30 Beijing time) and lasted for more than two hours; 3) with the blurred echoes gradually weakening,the traveling ionospheric disturbances (TIDs) still existed and became clearer; 4) the frequency shifts in the two cases were both positive,implying the effective reflecting surface of the radio wave in the ionosphere moved downwards.These results provide good observational evidence for daytime spread-F during the typhoon period in Asian region.

  18. Understanding motivations to participate in an observational research study: Why do patients enroll?

    Science.gov (United States)

    Soule, Michael C; Beale, Eleanor E; Suarez, Laura; Beach, Scott R; Mastromauro, Carol A; Celano, Christopher M; Moore, Shannon V; Huffman, Jeff C

    2016-01-01

    By understanding common motivations for participating in observational research studies, clinicians may better understand the perceived benefits of research participation from their clients' perspective. We enrolled 164 cardiac patients in a study about the effects of gratitude and optimism. Two weeks post-enrollment, participants completed a four-item questionnaire regarding motivations for study enrollment. Altruistic motivation ranked highest, while intellectual, health-related, and financial motivations rated lower. Four subgroups of participants emerged, each with distinct characteristics and different priorities for participating. These findings may help front-line clinicians to understand which motivations for participation apply to their clients who enroll in non-treatment-based research projects.

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

    Science.gov (United States)

    2016-05-01

    critical assessment for HEMI exposure under operational conditions. Certainly adding combinations of common pharmaceutical and/or abuse drug use should...and Drug Administration mA milliamperes JBSA Joint Base San Antonio HPW Human Performance Wing RHD Bioeffects Division AFI Air Force...arrhythmic drugs are recognized frequently to promote QT prolongation with subsequent development of TdP. This form of ventricular tachycardia can

  20. Adjacent segment degeneration: observations in a goat spinal fusion study

    NARCIS (Netherlands)

    R.J.W. Hoogendoorn; M.N. Helder; P.I.J.M. Wuisman; R.A. Bank; V. Everts; T.H. Smit

    2008-01-01

    Study Design. The adjacent discs of 13 goats, originally used in a lumbar spinal fusion model study, were analyzed for symptoms of intervertebral disc degeneration by means of magnetic resonance imaging (MRI), macroscopy, and histology. These goats were followed for 6 months and the results were com

  1. The Effect of Pulsar Timing Noise and Glitches on Timing Analysis for Ground Based Telescopes Observation

    Science.gov (United States)

    Oña-Wilhelmi, E.; de Jager, O. C.; Contreras, J. L.; de los Reyes, R.; Fonseca, V.; López, M.; Lucarelli, F.; MAGIC Collaboration

    2003-07-01

    Pulsed emission from a number of gamma-ray pulsars is expected to be detectable with next generation ground-based gamma-ray telescopes such as MAGIC and possibly H.E.S.S. within a few hours of observations. The sensitivity is however not sufficient to enable a detection within a few seconds as reached by radio surveys. In some cases we may be fortunate to do a period search given a few hours' data, but if the signal is marginal, the correct period parameters must be known to allow a folding of the gamma-ray arrival times. The residual phases are then sub jected to a test for uniformity from which the significance of a signal can be assessed. If contemporary radio parameters are not available, we have to extrap olate archival radio parameters to the observation time in question. Such an extrap olation must then be accurate enough to avoid significant pulse smearing. The pulsar ephemerides from the archival data of HartRAO and Princeton (b etween 1989 and 1998) provide an excellent opportunity to study the accuracy of extrap olations of such ephemerides to the present moment, if an appropriate time shift is intro duced. The aim of this study is to investigate the smear in the gamma-ray pulse profile during a single night of observations.

  2. Cassini CAPS-ELS observations of carbon-based anions and aerosol growth in Titan's ionosphere

    Science.gov (United States)

    Desai, Ravindra; Coates, Andrew; Wellbrock, Anne; Kataria, Dhiren; Jones, Geraint; Lewis, Gethyn; Waite, J.

    2016-06-01

    Cassini observations of Titans ionosphere revealed an atmosphere rich in positively charged ions with masses up to > 350 amu and negatively charged ions and aerosols with mass over charge ratios as high as 13,800 amu/q. The detection of negatively charged molecules by the Cassini CAPS Electron Spectrometer (CAPS-ELS) was particularly surprising and showed how the synthesis of large aerosol-size particles takes place at altitudes much greater than previously thought. Here, we present further analysis into this CAPS-ELS dataset, through an enhanced understanding of the instrument's response function. In previous studies the intrinsic E/E energy resolution of the instrument did not allow specific species to be identified and the detections were classified into broad mass ranges. In this study we use an updated fitting procedure to show how the ELS mass spectrum can be resolved into specific peaks at multiples of carbon-based anions up to > 100 amu/q. The negatively charged ions and aerosols in Titans ionosphere increase in mass with decreasing altitude, the lightest species being observed close to Titan's exobase of ˜1,450km and heaviest species observed at altitudes < 950km. We identify key stages in this apparent growth process and report on key intermediaries which appear to trigger the rapid growth of the larger aerosol-size particles.

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

    Science.gov (United States)

    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. Ground-based Observations of the Solar Sources of Space Weather

    Science.gov (United States)

    Veronig, A. M.; Pötzi, W.

    2016-04-01

    Monitoring of the Sun and its activity is a task of growing importance in the frame of space weather research and awareness. Major space weather disturbances at Earth have their origin in energetic outbursts from the Sun: solar flares, coronal mass ejections and associated solar energetic particles. In this review we discuss the importance and complementarity of ground-based and space-based observations for space weather studies. The main focus is drawn on ground-based observations in the visible range of the spectrum, in particular in the diagnostically manifold Hα spectral line, which enables us to detect and study solar flares, filaments (prominences), filament (prominence) eruptions, and Moreton waves. Existing Hα networks such as the GONG and the Global High-Resolution Hα Network are discussed. As an example of solar observations from space weather research to operations, we present the system of real-time detection of Hα flares and filaments established at Kanzelhöhe Observatory (KSO; Austria) in the frame of the space weather segment of the ESA Space Situational Awareness programme (swe.ssa.esa.int). An evaluation of the system, which is continuously running since July 2013 is provided, covering an evaluation period of almost 2.5 years. During this period, KSO provided 3020 hours of real-time Hα observations at the ESA SWE portal. In total, 824 Hα flares were detected and classified by the real-time detection system, including 174 events of Hα importance class 1 and larger. For the total sample of events, 95 % of the automatically determined flare peak times lie within ±5 min of the values given in the official optical flares reports (by NOAA and KSO), and 76 % of the start times. The heliographic positions determined are better than ±5°. The probability of detection of flares of importance 1 or larger is 95 %, with a false alarm rate of 16 %. These numbers confirm the high potential of automatic flare detection and alerting from ground-based

  5. An Evaluation of Lightning Flash Rate Parameterizations Based on Observations of Colorado Storms during DC3

    Science.gov (United States)

    Basarab, B.; Fuchs, B.; Rutledge, S. A.

    2013-12-01

    Predicting lightning activity in thunderstorms is important in order to accurately quantify the production of nitrogen oxides (NOx = NO + NO2) by lightning (LNOx). Lightning is an important global source of NOx, and since NOx is a chemical precursor to ozone, the climatological impacts of LNOx could be significant. Many cloud-resolving models rely on parameterizations to predict lightning and LNOx since the processes leading to charge separation and lightning discharge are not yet fully understood. This study evaluates predicted flash rates based on existing lightning parameterizations against flash rates observed for Colorado storms during the Deep Convective Clouds and Chemistry Experiment (DC3). Evaluating lightning parameterizations against storm observations is a useful way to possibly improve the prediction of flash rates and LNOx in models. Additionally, since convective storms that form in the eastern plains of Colorado can be different thermodynamically and electrically from storms in other regions, it is useful to test existing parameterizations against observations from these storms. We present an analysis of the dynamics, microphysics, and lightning characteristics of two case studies, severe storms that developed on 6 and 7 June 2012. This analysis includes dual-Doppler derived horizontal and vertical velocities, a hydrometeor identification based on polarimetric radar variables using the CSU-CHILL radar, and insight into the charge structure using observations from the northern Colorado Lightning Mapping Array (LMA). Flash rates were inferred from the LMA data using a flash counting algorithm. We have calculated various microphysical and dynamical parameters for these storms that have been used in empirical flash rate parameterizations. In particular, maximum vertical velocity has been used to predict flash rates in some cloud-resolving chemistry simulations. We diagnose flash rates for the 6 and 7 June storms using this parameterization and compare

  6. Theory and experiment of observer based magnetostrictive self-sensing actuator

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Giant magnetostrictive actuators (GMAs) often work in a close-loop feedback system. This system needs independent sensors which may be difficult to be fixed, besides, excessive sensors may cause more unpredicted problems in a large system.This paper aims to develop a self-sensing GMA. An observer based on piezomagnetic equations is constructed to estimate the stress and strain of the magnetostrictive material. The observer based self-sensing approach depends on the facts that the magnetic field is controllable and that the magnetic induction is measurable. Aiming at the nonlinear hysteresis in magnetization, a hysteresis compensation observer based on Preisach model is developed. Experiment verified the availability of the observer approach,and the hysteresis compensation observer has higher tracking precision than linear observer for dynamic force sensing.

  7. A submllimeter observation and study of star-forming regions

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Using the 3-m radio telescope of KOSMA, we mapped 12CO (J = 3-2) lines for three molecular clouds, B35, S146 and TMC-2A. High-velocity molecular outflows are found in all these regions. The physical and dynamical parameters of the outflows are derived, and their shapes and driving sources are analyzed. Contour maps of center velocities show that the large scale systematic gradients exist in the three clouds. These observed motions are best explained by rotation after excluding the cause of outflows. Furthermore, in the core region of TMC-2A there is a velocity gradient in opposite direction from that of the large scale. It may be caused by magnetic braking. Finally, angular velocities of the clouds are calculated, and the effects of rotation against gravity and lowering the star-formation rate are also analyzed.

  8. Leflunomide in Takayasu arteritis – A long term observational study

    OpenAIRE

    Souza, Alexandre Wagner Silva de [UNIFESP; Agustinelli,Renan de Almeida; Almeida,Hemerli de Cinque; Oliveira,Patrícia Bermudes; Pinheiro,Frederico Augusto Gurgel; Oliveira,Ana Cecilia Diniz; Sato, Emilia Inoue [UNIFESP

    2016-01-01

    ABSTRACT Objective: To evaluate the extended follow-up data on efficacy and toxicity of leflunomide therapy in Takayasu arteritis (TA) patients previously enrolled in the original open-label study of short-term effects of leflunomide in TA. Methods: An open-label long-term longitudinal study was performed in TA patients who fulfilled the 1990 American College of Rheumatology criteria for TA and had participated in a previous study that evaluated short-term efficacy of leflunomide in TA. Com...

  9. Satellite Based Soil Moisture Product Validation Using NOAA-CREST Ground and L-Band Observations

    Science.gov (United States)

    Norouzi, H.; Campo, C.; Temimi, M.; Lakhankar, T.; Khanbilvardi, R.

    2015-12-01

    Soil moisture content is among most important physical parameters in hydrology, climate, and environmental studies. Many microwave-based satellite observations have been utilized to estimate this parameter. The Advanced Microwave Scanning Radiometer 2 (AMSR2) is one of many remotely sensors that collects daily information of land surface soil moisture. However, many factors such as ancillary data and vegetation scattering can affect the signal and the estimation. Therefore, this information needs to be validated against some "ground-truth" observations. NOAA - Cooperative Remote Sensing and Technology (CREST) center at the City University of New York has a site located at Millbrook, NY with several insitu soil moisture probes and an L-Band radiometer similar to Soil Moisture Passive and Active (SMAP) one. This site is among SMAP Cal/Val sites. Soil moisture information was measured at seven different locations from 2012 to 2015. Hydra probes are used to measure six of these locations. This study utilizes the observations from insitu data and the L-Band radiometer close to ground (at 3 meters height) to validate and to compare soil moisture estimates from AMSR2. Analysis of the measurements and AMSR2 indicated a weak correlation with the hydra probes and a moderate correlation with Cosmic-ray Soil Moisture Observing System (COSMOS probes). Several differences including the differences between pixel size and point measurements can cause these discrepancies. Some interpolation techniques are used to expand point measurements from 6 locations to AMSR2 footprint. Finally, the effect of penetration depth in microwave signal and inconsistencies with other ancillary data such as skin temperature is investigated to provide a better understanding in the analysis. The results show that the retrieval algorithm of AMSR2 is appropriate under certain circumstances. This validation algorithm and similar study will be conducted for SMAP mission. Keywords: Remote Sensing, Soil

  10. Observational study of food safety practices in retail deli departments.

    Science.gov (United States)

    Lubran, M B; Pouillot, R; Bohm, S; Calvey, E M; Meng, J; Dennis, S

    2010-10-01

    In order to improve the safety of refrigerated ready-to-eat food products prepared at retail deli departments, a better understanding of current practices in these establishments is needed. Food employees in deli departments at six chain and three independent retail establishments in Maryland and Virginia were observed, using notational analysis, as they prepared deli products for sale. The frequency of contact with objects and deli products before sale, hand washing and glove changing during preparation, and equipment, utensil, and surface cleaning and sanitizing was determined. Compliance with the U.S. Food and Drug Administration's 2005 model Food Code recommendations, which must be adopted by the individual state and local jurisdictions that are responsible for directly regulating retail establishments, was also assessed. Observations indicated there were a large number of actions for which hand washing was recommended at independent and chain stores (273 recommended of 1,098 total actions and 439 recommended of 3,073 total actions, respectively). Moreover, 67% (295 of 439) of the actions for which hand washing was recommended at the chain stores and 86% (235 of 273) of those at the independent stores resulted from employees touching non-food contact surfaces prior to handling ready-to-eat food. Compliance with hand washing recommendations was generally low and varied depending on store type with independent stores exhibiting lower compliance than chain stores (5 instances of compliance for 273 recommended actions and 73 instances of compliance for 439 recommended actions, respectively). Potential risk mitigation measures that may reduce the frequency of hand washing actions needed during ready-to-eat food preparation in retail deli departments are discussed. More research is needed to determine the impact of such measures on food safety.

  11. Observational studies on evaluating the safety and adverse effects of traditional chinese medicine.

    Science.gov (United States)

    Lai, Jung-Nein; Tang, Jin-Ling; Wang, Jung-Der

    2013-01-01

    Background. This study aims to share our experiences when carrying out observational studies of traditional Chinese medicine (TCM). Methods. We have proactively monitored the safety profiles of Duhuo Jisheng Tang (DJT), Suan Zao Ren Tang (SZRT), and TMN-1. A list of adverse events (AEs), complete blood counts, and liver and kidney function tests were obtained from the participants during their scheduled hospital visits. Retrospective observational studies were conducted based on the reimbursement database of the National Health Insurance system, Taiwan, to explore the relationship between the use of TCM that have been adulterated by aristolochic acid and the risk from both nephrotoxins and carcinogens. Results. A total of 221, 287, and 203 AEs were detected after SZRT, DJT, and TMN-1 had been taken, respectively. Dizziness, headache, stomach ache, and diarrhea were judged to be probably related to SZRT treatment. Retrospective observational studies found an association between the consumption of aristolochic acid-containing Chinese formulae such as Mu Tong and an increased risk of CKD, ESRD, and urinary tract cancer. Conclusion. Prospective and retrospective observational studies seem to have specific advantages when investigating the safety and adverse effects of TCM therapies, as well as possibly other alternative/complementary therapies.

  12. Observational Studies on Evaluating the Safety and Adverse Effects of Traditional Chinese Medicine

    Directory of Open Access Journals (Sweden)

    Jung-Nein Lai

    2013-01-01

    Full Text Available Background. This study aims to share our experiences when carrying out observational studies of traditional Chinese medicine (TCM. Methods. We have proactively monitored the safety profiles of Duhuo Jisheng Tang (DJT, Suan Zao Ren Tang (SZRT, and TMN-1. A list of adverse events (AEs, complete blood counts, and liver and kidney function tests were obtained from the participants during their scheduled hospital visits. Retrospective observational studies were conducted based on the reimbursement database of the National Health Insurance system, Taiwan, to explore the relationship between the use of TCM that have been adulterated by aristolochic acid and the risk from both nephrotoxins and carcinogens. Results. A total of 221, 287, and 203 AEs were detected after SZRT, DJT, and TMN-1 had been taken, respectively. Dizziness, headache, stomach ache, and diarrhea were judged to be probably related to SZRT treatment. Retrospective observational studies found an association between the consumption of aristolochic acid-containing Chinese formulae such as Mu Tong and an increased risk of CKD, ESRD, and urinary tract cancer. Conclusion. Prospective and retrospective observational studies seem to have specific advantages when investigating the safety and adverse effects of TCM therapies, as well as possibly other alternative/complementary therapies.

  13. Propensity score modelling in observational studies using dimension reduction methods.

    Science.gov (United States)

    Ghosh, Debashis

    2011-07-01

    Conditional independence assumptions are very important in causal inference modelling as well as in dimension reduction methodologies. These are two very strikingly different statistical literatures, and we study links between the two in this article. The concept of covariate sufficiency plays an important role, and we provide theoretical justification when dimension reduction and partial least squares methods will allow for valid causal inference to be performed. The methods are illustrated with application to a medical study and to simulated data.

  14. Entry Dispersion Analysis for the Hayabusa Spacecraft using Ground Based Optical Observation

    CERN Document Server

    Yamaguchi, T; Yagi, M; Tholen, D J

    2011-01-01

    Hayabusa asteroid explorer successfully released the sample capsule to Australia on June 13, 2010. Since the Earth reentry phase of sample return was critical, many backup plans for predicting the landing location were prepared. This paper investigates the reentry dispersion using ground based optical observation as a backup observation for radiometric observation. Several scenarios are calculated and compared for the reentry phase of the Hayabusa to evaluate the navigation accuracy of the ground-based observation. The optical observation doesn't require any active reaction from a spacecraft, thus these results show that optical observations could be a steady backup strategy even if a spacecraft had some trouble. We also evaluate the landing dispersion of the Hayabusa only with the optical observation.

  15. The transient observation-based particle (TOP model and its potential application in radiation effects evaluation

    Directory of Open Access Journals (Sweden)

    Benck Sylvie

    2013-01-01

    Full Text Available The evaluation of the radiation hazards on components used in space environment is based on the knowledge of the radiation level encountered on orbit. The models that are widely used to assess the near-Earth environment for a given mission are empirical trapped radiation models derived from a compilation of spacecraft measurements. However, these models are static and hence are not suited for describing the short timescale variations of geomagnetic conditions. The transient observation-based particle (TOP-model tends to break with this classical approach by introducing dynamic features based on the observation and characterization of transient particle flux events in addition to classical mapping of steady-state flux levels. In order to get a preliminary version of an operational model (actually only available for electrons at low Earth orbit, LEO, (i the steady-state flux level, (ii the flux enhancements probability distribution functions, and (iii the flux decay-time constants (at given energy and positions in space were determined, and an original dynamic model skeleton with these input parameters has been developed. The methodology is fully described and first flux predictions from the model are presented. In order to evaluate the net effects of radiation on a component, it is important to have an efficient tool that calculates the transfer of the outer radiation environment through the spacecraft material, toward the location of the component under investigation. Using the TOP-model space radiation fluxes and the transmitted radiation environment characteristics derived through GEANT4 calculations, a case study for electron flux/dose variations in a small silicon volume is performed. Potential cases are assessed where the dynamic of the spacecraft radiation environment may have an impact on the observed radiation effects.

  16. Leflunomide in Takayasu arteritis – A long term observational study

    Directory of Open Access Journals (Sweden)

    Alexandre Wagner Silva de Souza

    Full Text Available ABSTRACT Objective: To evaluate the extended follow-up data on efficacy and toxicity of leflunomide therapy in Takayasu arteritis (TA patients previously enrolled in the original open-label study of short-term effects of leflunomide in TA. Methods: An open-label long-term longitudinal study was performed in TA patients who fulfilled the 1990 American College of Rheumatology criteria for TA and had participated in a previous study that evaluated short-term efficacy of leflunomide in TA. Complete follow-up information could be retrieved from 12 out of 15 patients enrolled in the original study. Disease activity was evaluated by Kerr's criteria and by the Indian Takayasu Activity Score 2010 (ITAS2010. Results: The mean follow up time was 43.0 ± 7.6 months and 5 (41.6% TA patients remained on leflunomide therapy while 7 (58.3% TA patients had to change to another therapy due to failure to prevent relapses in 6 patients and toxicity in one patient. No significant differences were found between patients who remained on leflunomide therapy and those who changed to another agent regarding age at study entry, time since diagnosis, prednisone daily dose at study entry, baseline ITAS2010, mean or maximum ESR and CRP, and cumulative prednisone dose at study end. Among TA patients who had changed leflunomide to another agent, two had an additional clinical relapse and needed to change therapy. Conclusion: Leflunomide led to sustained remission in approximately half of patients at a mean time of 12 months and was well tolerated by TA patients.

  17. Observational research methods—Cohort studies, cross sectional studies, and case–control studies

    Directory of Open Access Journals (Sweden)

    C.J. Mann

    2012-03-01

    Cohort studies are used to study incidence, causes, and prognosis. Because they measure events in chronological order they can be used to distinguish between cause and effect. Cross sectional studies are used to determine prevalence. They are relatively quick and easy but do not permit distinction between cause and effect. Case controlled studies compare groups retrospectively. They seek to identify possible predictors of outcome and are useful for studying rare diseases or outcomes. They are often used to generate hypotheses that can then be studied via prospective cohort or other studies.

  18. A foundational observation method for studying design situations

    DEFF Research Database (Denmark)

    Cash, Philip; Hicks, Ben; Culley, Steve;

    2015-01-01

    that covers capture, coding, and analysis. The capture step defines overall and situational context as well as multiple capture streams, generating a broad data-set that can be examined from multiple perspectives. The coding step employs a multi-level approach that seeks to minimise workload while describing...... both detailed and high-level information. The analysis step builds on the multi-level approach to provide for a flexible yet standardised examination of the data-set. The overall approach is introduced theoretically and illustrated using a comparison of an industrial study and an experimental study...

  19. Comparing the incomparable: hemodialysis versus peritoneal dialysis in observational studies.

    Science.gov (United States)

    Foley, Robert N

    2004-01-01

    A randomized trial comparing survival in hemodialysis and peritoneal dialysis remains a utopian aspiration. Dialysis is still relatively rare on a population basis, and a natural tension exists between desirability and feasibility in terms of quality of evidence. In practice, it is very difficult to perform prospective comparisons with large groups of contemporary representative subjects, and much of the literature comes from retrospective national registries. This article considers several questions to address when trying to compare the outcomes of peritoneal dialysis and hemodialysis. Prognostic similarity at baseline is a fundamental issue. Traditionally, adjustment for known prognostic factors has been used in an attempt to minimize the bias caused by nonrandom treatment assignment. Propensity scores have been suggested to be superior, and matched-case analysis may also be a useful method for comparison. Other questions include, when, in relation to starting dialysis, to start the observation clock; the definition and handling of switches of dialysis therapy; and the decision to censor at transplantation. Finally, comparisons are complicated by hazards ratios that vary over time, and time-segmented analysis is obligatory. Many types of analytical approaches are needed to begin to appreciate outcome disparities between dialysis therapies.

  20. HEMATOLOGICAL MANIFESTATIONS IN DENGUE FEVER – AN OBSERVATIONAL STUDY

    Directory of Open Access Journals (Sweden)

    Malathesha

    2014-02-01

    Full Text Available BACKGROUND: Dengue is a major preventable and treatable cause of morbidity and mortality among children and adults that occurs mainly in tropical and subtropical regions. Early diagnosis of dengue is important for provision of specific care which ensures marked reduction in the morbidity of the disease itself. OBJECTIVE: To evaluate hematological changes in serologically proven patients with clinical manifestations of Dengue in Bapuji & Chigateri Hospital, Davangere. METHODS: Clinical, hematological and serological information from Patients diagnosed with dengue infection in Bapuji & Chigateri hospital Davangere from April 2013 -June 2013. RESULTS: 221 cases of classic dengue predominated (90.2%, with mild clinical manifestations lacking complications. The main hematological findings were raised hematocrit (79.6%, lymphocytosis (66% monocytosis (84.6%, basophilia (52.9%, thrombocytopenia (100% and atypical lymphocytes (87%. In dengue hemorrhagic fever, thrombocytopenia was more prolonged and the number of atypical lymphocytes was higher, while the other hematological abnormalities presented daily evolution similar to those in classic dengue. The hematological changes observed in dengue presented according to the clinical course of the disease and its severity

  1. Ground Observations of Post-Noon Aurora :a Case Study

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The characteristics of the post-noon aurora observed at Antarctic Zhongshan station on June 12, 1999, were discussed and analyzed. In the condition of the magnetic activity is not large(Kp≈l), for post-noon 630. 0 nm emissions, the total fluxes of soft precipitating particles were increasing from 10:50 UT to 13:35 UT and were decreasing from 13 :35 UT to 18 :00 UT in almost monotonous way. Away from noon, the 557. 7 nm emissions increased gradually from 10 :50 UT to 17 :10 UT. The behaviors of the precipitat- ing particles for exciting 630. 0 nm aurora and 557. 7 nm aurora were quite different. The peak intensity of 630. 0 nm and 557. 7 nm emissions appeared at about 13:35 UT and 15:40 UT respectively, the time differ- ence of two peaks is about 2 h. The energy of precipitating electrons remained fairly steady until 15:00 UT when it rose dramatically.

  2. Observer-based fault detection scheme for a class of discrete time-delay systems

    Institute of Scientific and Technical Information of China (English)

    Zhong Maiying(钟麦英); Zhang Chenghui(张承慧); Ding Steven X; Lam James

    2004-01-01

    In this contribution, robust fault detection problems for discrete time-delay systems with l2-norm bounded un-known inputs are studied. The basic idea of our study is first to introduce a state-memoryless observer-based fault detec-tion filter (FDF) as the residual generator and then to formulate such a FDF design problem as an H∞ optimization prob-lem in the sense of increasing the sensitivity of residual to the faults, while simultaneously enhancing the robustness of residual to unknown input as well as plant input. The main results consist of the formulation of such a residual generation optimization problem, solvability conditions and the derivation of an analytic solution. The residual evaluation problem is also considered, which includes the determination of residual evaluation function and threshold. A numerical example is used to demonstrate the proposed fault detection scheme.

  3. Writing Instruction in First Grade: An Observational Study

    Science.gov (United States)

    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…

  4. An Observational Study of Social Behavior in Microcomputer Classrooms.

    Science.gov (United States)

    Feldmann, Shirley C.; And Others

    1991-01-01

    This study examined the effects of five variables--student grouping at the computer, keyboarding status, academic discipline, student gender, and gender of partner--on student social behavior, both verbal and affective, in microcomputer classrooms in a public business high school. The effect of these variables on teacher behavior was also…

  5. Understanding the equatorial ocean : theoretical and observational studies

    NARCIS (Netherlands)

    Rabitti, A.

    2016-01-01

    By means of a variety of approaches, the present study points out the challenges in understanding equatorial ocean dynamics (±2.5º). Standard theory, in fact, fails in accurately describing such a big portion of our ocean. This is mainly because at the equator rotation and density stratification com

  6. Fine spectral structures in Jovian decametric radio emission observed by ground-based radio telescope.

    Science.gov (United States)

    Panchenko, M.; Brazhenko, A. I.; Shaposhnikov, V. E.; Konovalenko, A. A.; Rucker, H. O.

    2014-04-01

    Jupiter with the largest planetary magnetosphere in the solar system emits intense coherent non-thermal radio emission in a wide frequency range. This emission is a result of a complicated interaction between the dynamic Jovian magnetosphere and energetic particles supplying the free energy from planetary rotation and the interaction between Jupiter and the Galilean moons. Decametric radio emission (DAM) is the strongest component of Jovian radiation observed in a frequency range from few MHz up to 40 MHz. This emission is generated via cyclotron maser mechanism in sources located along Jovian magnetic field lines. Depending on the time scales the Jovian DAMexhibits different complex spectral structures. We present the observations of the Jovian decametric radio emission using the large ground-based radio telescope URAN- 2 (Poltava, Ukraine) operated in the decametric frequency range. This telescope is one of the largest low frequency telescopes in Europe equipped with high performance digital radio spectrometers. The antenna array of URAN-2 consists of 512 crossed dipoles with an effective area of 28 000m2 and beam pattern size of 3.5 x 7 deg. (at 25 MHz). The instrument enables continuous observations of the Jovian radio during long period of times. Jovian DAM was observed continuously since Sep. 2012 (depending on Jupiter visibility) with relatively high time-frequency resolution (4 kHz - 100ms) in the broad frequency range (8-32MHz). We have detected a big amount of the fine spectral structures in the dynamic spectra of DAM such as trains of S-bursts, quasi-continuous narrowband emission, narrow-band splitting events and zebra stripe-like patterns. We analyzed mainly the fine structures associated with non-Io controlled DAM. We discuss how the observed narrowband structures which most probably are related to the propagation of the decametric radiation in the Jupiter's ionosphere can be used to study the plasma parameters in the inner Jovian magnetosphere.

  7. Precision Studies of Observables in $pp \\to W \\to \\ell \

    Energy Technology Data Exchange (ETDEWEB)

    Alioli, S.; et al.

    2016-06-07

    This report was prepared in the context of the LPCC "Electroweak Precision Measurements at the LHC WG" and summarizes the activity of a subgroup dedicated to the systematic comparison of public Monte Carlo codes, which describe the Drell-Yan processes at hadron colliders, in particular at the CERN Large Hadron Collider (LHC). This work represents an important step towards the definition of an accurate simulation framework necessary for very high-precision measurements of electroweak (EW) observables such as the $W$ boson mass and the weak mixing angle. All the codes considered in this report share at least next-to-leading-order (NLO) accuracy in the prediction of the total cross sections in an expansion either in the strong or in the EW coupling constant. The NLO fixed-order predictions have been scrutinized at the technical level, using exactly the same inputs, setup and perturbative accuracy, in order to quantify the level of agreement of different implementations of the same calculation. A dedicated comparison, again at the technical level, of three codes that reach next-to-next-to-leading-order (NNLO) accuracy in quantum chromodynamics (QCD) for the total cross section has also been performed. These fixed-order results are a well-defined reference that allows a classification of the impact of higher-order sets of radiative corrections. Several examples of higher-order effects due to the strong or the EW interaction are discussed in this common framework. Also the combination of QCD and EW corrections is discussed, together with the ambiguities that affect the final result, due to the choice of a specific combination recipe.

  8. Simultaneous ground- and satellite-based observation of MF/HF auroral radio emissions

    Science.gov (United States)

    Sato, Yuka; Kumamoto, Atsushi; Katoh, Yuto; Shinbori, Atsuki; Kadokura, Akira; Ogawa, Yasunobu

    2016-05-01

    We report on the first simultaneous measurements of medium-high frequency (MF/HF) auroral radio emissions (above 1 MHz) by ground- and satellite-based instruments. Observational data were obtained by the ground-based passive receivers in Iceland and Svalbard, and by the Plasma Waves and Sounder experiment (PWS) mounted on the Akebono satellite. We observed two simultaneous appearance events, during which the frequencies of the auroral roar and MF bursts detected at ground level were different from those of the terrestrial hectometric radiation (THR) observed by the Akebono satellite passing over the ground-based stations. This frequency difference confirms that auroral roar and THR are generated at different altitudes across the F peak. We did not observe any simultaneous observations that indicated an identical generation region of auroral roar and THR. In most cases, MF/HF auroral radio emissions were observed only by the ground-based detector, or by the satellite-based detector, even when the satellite was passing directly over the ground-based stations. A higher detection rate was observed from space than from ground level. This can primarily be explained in terms of the idea that the Akebono satellite can detect THR emissions coming from a wider region, and because a considerable portion of auroral radio emissions generated in the bottomside F region are masked by ionospheric absorption and screening in the D/E regions associated with ionization which results from auroral electrons and solar UV radiation.

  9. Lightning climatology over Jakarta, Indonesia, based on long-term surface operational, satellite, and campaign observations

    Science.gov (United States)

    Mori, Shuichi; Wu, Peiming; Yamanaka, Manabu D.; Hattori, Miki; Hamada, Jun-Ichi; Arbain, Ardhi A.; Lestari, Sopia; Sulistyowati, Reni; Syamsudin, Fadli

    2016-04-01

    Lightning frequency over Indonesian Maritime Continent (MC) is quite high (Petersen and Rutledge 2001, Christian et al. 2003, Takayabu 2006, etc). In particular, Bogor (south of Jakarta, west Jawa) had 322 days of lightning in one year (Guinness Book in 1988). Lightning causes serious damage on nature and society over the MC; forest fore, power outage, inrush/surge currents on many kinds of electronics. Lightning climatology and meso-scale characteristics of thunderstorm over the MC, in particular over Jakarta, where social damage is quite serious, were examined. We made Statistical analysis of lightning and thunderstorm based on TRMM Lightning Image Sensor (LIS) and Global Satellite Mapping of Precipitation (GSMaP) together with long-term operational surface observation data (SYNOP) in terms of diurnal, intraseasonal, monsoonal, and interannual variations. In addition, we carried out a campaign observation in February 2015 in Bogor to obtain meso-scale structure and dynamics of thunderstorm over Jakarta to focus on graupel and other ice phase particles inside by using an X-band dual-polarimetric (DP) radar. Recently, Virts et al. (2013a, b) showed comprehensive lightning climatology based on the World Wide Lightning Location Network (WWLLN). However, they also reported problems with its detection efficiency (< 10%) and small sampling frequency (< 0.1% of the time fly over tropics) by satellites. Therefore, we firstly examine in situ lightning data based on SYNOP observed by the Indonesian Agency for Meteorology, Climatology, and Geophysics (BMKG) because lightning is quite local and sporadic phenomena. We've started to analyze lightning characteristics over Jakarta region based on SYNOP as the ground truth data and GSMaP. Variability of lightning frequency around Jakarta was affected much by local conditions, e.g., topography (elevation) and proximity to the coastline. We confirmed the lightning frequency and its diurnal variation around Jakarta were much

  10. A Big-Data-based platform of workers' behavior: Observations from the field.

    Science.gov (United States)

    Guo, S Y; Ding, L Y; Luo, H B; Jiang, X Y

    2016-08-01

    Behavior-Based Safety (BBS) has been used in construction to observe, analyze and modify workers' behavior. However, studies have identified that BBS has several limitations, which have hindered its effective implementation. To mitigate the negative impact of BBS, this paper uses a case study approach to develop a Big-Data-based platform to classify, collect and store data about workers' unsafe behavior that is derived from a metro construction project. In developing the platform, three processes were undertaken: (1) a behavioral risk knowledge base was established; (2) images reflecting workers' unsafe behavior were collected from intelligent video surveillance and mobile application; and (3) images with semantic information were stored via a Hadoop Distributed File System (HDFS). The platform was implemented during the construction of the metro-system and it is demonstrated that it can effectively analyze semantic information contained in images, automatically extract workers' unsafe behavior and quickly retrieve on HDFS as well. The research presented in this paper can enable construction organizations with the ability to visualize unsafe acts in real-time and further identify patterns of behavior that can jeopardize safety outcomes.

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

    OpenAIRE

    Beerstecher Hendrik J; Rhys Gwion; Morgan Claire L

    2010-01-01

    Abstract 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 f...

  12. Renal colic, where is it headed? An observational study

    OpenAIRE

    Paolo Beltrami; Andrea Guttilla; Lorenzo Ruggera; Patrizia Bernich; Filiberto Zattoni

    2016-01-01

    Aim: In the last thirty years, the treatment for renal and ureteral calculi has undergone profound variations. The objective of this study has been to evaluate the existence of parameters which can affect the spontaneous expulsion of a symptomatic ureteral stone in a reasonably brief period of time and to identify whether certain parameters such as sex, age, the location and dimension of the stone, the presence of dilation in the urinary tract together with the administered therapy, can be us...

  13. OBSERVATIONAL STUDY OF LIGHTNING CHARACTERISTICS IN HAIL-PRODUCING CLOUDS

    Institute of Scientific and Technical Information of China (English)

    LI Zhao-rong; FU Shuang-xi; LI Bao-zi; JIANG Lin

    2006-01-01

    @@ 1 INTRODUCTION Lightning is a phenomenon of atmospheric electricity with convective storms. Since the 1960's, its characteristics during weather processes of torrential rain, hails and tornadoes have been widely studied and a lot of attempts made to probe into the mechanisms responsible for the formation of lightning[1], giving rise to two theories explaining the lightning genesis, from the points of convection and ice-phase precipitation,respectively.

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

    Directory of Open Access Journals (Sweden)

    Pankaj Kumar Garg

    2013-01-01

    Full Text Available 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 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.

  15. High-Gain Approach Based Full-Order Observers for Linear Systems with Unknown Inputs

    Institute of Scientific and Technical Information of China (English)

    韩冬; 刘俊

    2016-01-01

    In this paper, a full-order observer which can be fully decoupled from the unknown inputs as the con-ventional full-order observer does is designed by using auxiliary outputs, but the requirement of the matching con-dition is removed. The procedure of calculating the parameter matrices of the full-order observer is also presented. Compared with the existing auxiliary outputs based sliding-mode observers, the designed observer has a simpler design procedure, which is systematic and does not involve solving linear matrix inequalities. The simulation re-sults show that the proposed method is effective.

  16. Observer based projective reduced-order synchronization of different chaotic systems

    Institute of Scientific and Technical Information of China (English)

    LI Guan-lin; CHEN Xi-you; LIU Feng-chun; MU Xian-min

    2010-01-01

    The projective reduced-order synchronization of two different chaotic systems with different orders is investigated based on the observer design in this paper.According to the observer theory,the reduced-order observer is designed.The projective synchronization can be realized by choosing the transition matrix of the observer as a diagonal matrix.Further,the synchronization between hyperchaotic Chen system(fourth order)and R(o)ssler system(third order)is taken as the example to demonstrate the effectiveness of the proposed observer.Numerical simulations confirm the effectiveness of the method.

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

    Science.gov (United States)

    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 (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.

  18. Water balance-based actual evapotranspiration reconstruction from ground and satellite observations over the conterminous United States

    Science.gov (United States)

    Wan, Zhanming; Zhang, Ke; Xue, Xianwu; Hong, Zhen; Hong, Yang; Gourley, Jonathan J.

    2015-08-01

    The objective of this study is to produce an observationally based monthly evapotranspiration (ET) product using the simple water balance equation across the conterminous United States (CONUS). We adopted the best quality ground and satellite-based observations of the water budget components, i.e., precipitation, runoff, and water storage change, while ET is computed as the residual. Precipitation data are provided by the bias-corrected PRISM observation-based precipitation data set, while runoff comes from observed monthly streamflow values at 592 USGS stream gauging stations that have been screened by strict quality controls. We developed a land surface model-based downscaling approach to disaggregate the monthly GRACE equivalent water thickness data to daily, 0.125° values. The derived ET computed as the residual from the water balance equation is evaluated against three sets of existing ET products. The similar spatial patterns and small differences between the reconstructed ET in this study and the other three products show the reliability of the observationally based approach. The new ET product and the disaggregated GRACE data provide a unique, important hydro-meteorological data set that can be used to evaluate the other ET products as a benchmark data set, assess recent hydrological and climatological changes, and terrestrial water and energy cycle dynamics across the CONUS. These products will also be valuable for studies and applications in drought assessment, water resources management, and climate change evaluation.

  19. Switched-Observer-Based Adaptive Neural Control of MIMO Switched Nonlinear Systems With Unknown Control Gains.

    Science.gov (United States)

    Long, Lijun; Zhao, Jun

    2016-05-02

    In this paper, the problem of adaptive neural output-feedback control is addressed for a class of multi-input multioutput (MIMO) switched uncertain nonlinear systems with unknown control gains. Neural networks (NNs) are used to approximate unknown nonlinear functions. In order to avoid the conservativeness caused by adoption of a common observer for all subsystems, an MIMO NN switched observer is designed to estimate unmeasurable states. A new switched observer-based adaptive neural control technique for the problem studied is then provided by exploiting the classical average dwell time (ADT) method and the backstepping method and the Nussbaum gain technique. It effectively handles the obstacle about the coexistence of multiple Nussbaum-type function terms, and improves the classical ADT method, since the exponential decline property of Lyapunov functions for individual subsystems is no longer satisfied. It is shown that the technique proposed is able to guarantee semiglobal uniformly ultimately boundedness of all the signals in the closed-loop system under a class of switching signals with ADT, and the tracking errors converge to a small neighborhood of the origin. The effectiveness of the approach proposed is illustrated by its application to a two inverted pendulum system.

  20. Spatial Estimation of Sub-Hour Global Horizontal Irradiance Based on Official Observations and Remote Sensors

    Science.gov (United States)

    Gutierrez-Corea, Federico-Vladimir; Manso-Callejo, Miguel-Angel; Moreno-Regidor, María-Pilar; Velasco-Gómez, Jesús

    2014-01-01

    This study was motivated by the need to improve densification of Global Horizontal Irradiance (GHI) observations, increasing the number of surface weather stations that observe it, using sensors with a sub-hour periodicity and examining the methods of spatial GHI estimation (by interpolation) with that periodicity in other locations. The aim of the present research project is to analyze the goodness of 15-minute GHI spatial estimations for five methods in the territory of Spain (three geo-statistical interpolation methods, one deterministic method and the HelioSat2 method, which is based on satellite images). The research concludes that, when the work area has adequate station density, the best method for estimating GHI every 15 min is Regression Kriging interpolation using GHI estimated from satellite images as one of the input variables. On the contrary, when station density is low, the best method is estimating GHI directly from satellite images. A comparison between the GHI observed by volunteer stations and the estimation model applied concludes that 67% of the volunteer stations analyzed present values within the margin of error (average of ±2 standard deviations). PMID:24732102

  1. Periodontal disease and risk of chronic obstructive pulmonary disease: a meta-analysis of observational studies.

    Directory of Open Access Journals (Sweden)

    Xian-Tao Zeng

    Full Text Available BACKGROUND: Many epidemiological studies have found a positive association between periodontal disease (PD and risk of chronic obstructive pulmonary disease (COPD, but this association is varied and even contradictory among studies. We performed a meta-analysis to ascertain the relationship between PD and COPD. METHODS: PubMed and Embase database were searched up to January 10, 2012, for relevant observational studies on the association between PD and risk of COPD. Data from the studies selected were extracted and analyzed independently by two authors. The meta-analysis was performed using the Comprehensive Meta-Analysis software. RESULTS: Fourteen observational studies (one nested case-control, eight case-control, and five cross-sectional involving 3,988 COPD patients were yielded. Based on random-effects meta-analysis, a significant association between PD and COPD was identified (odds ratio = 2.08, 95% confidence interval = 1.48-2.91; P<0.001, with sensitivity analysis showing that the result was robust. Subgroups analyses according to study design, ethnicity, assessment of PD/COPD, and adjusted/unadjusted odds ratios also revealed a significant association. Publication bias was detected. CONCLUSIONS: Based on current evidence, PD is a significant and independent risk factor of COPD. However, whether a causal relationships exists remains unclear. Morever, we suggest performing randomized controlled trails to explore whether periodontal interventions are beneficial in regulating COPD pathogenesis and progression.

  2. Comparison of Thermal Structure Results from Venus Express and Ground Based Observations since Vira

    Science.gov (United States)

    Limaye, Sanjay

    2016-07-01

    An international team was formed in 2013 through the International Space Studies Institute (Bern, Switzerland) to compare recent results of the Venus atmospheric thermal structure from spacecraft and ground based observations made since the Venus International Reference Atmosphere (VIRA) was developed (Kliore et al., 1985, Keating et al., 1985). Five experiments on European Space Agency's Venus Express orbiter mission have yielded results on the atmospheric structure during is operational life (April 2006 - November 2014). Three of these were from occultation methods: at near infrared wavelengths from solar occultations, (SOIR, 70 - 170 km), at ultraviolet wavelengths from stellar occultations (SPICAV, 90-140 km), and occultation of the VEx-Earth radio signal (VeRa, 40-90 km). In-situ drag measurements from three different techniques (accelerometry, torque, and radio tracking, 130 - 200 km) were also obtained using the spacecraft itself while passive infrared remote sensing was used by the VIRTIS experiment (70 - 120 km). The only new data in the -40-70 km altitude range are from radio occultation, as no new profiles of the deep atmosphere have been obtained since the VeGa 2 lander measurements in 1985 (not included in VIRA). Some selected ground based results available to the team were also considered by team in the inter comparisons. The temperature structure in the lower thermosphere from disk resolved ground based observations (except for one ground based investigation), is generally consistent with the Venus Express results. These experiments sampled at different periods, at different locations and at different local times and have different vertical and horizontal resolution and coverage. The data were therefore binned in latitude and local time bins and compared, ignoring temporal variations over the life time of the Venus Express mission and assumed north-south symmetry. Alternating warm and cooler layers are present in the 120-160 altitude range in results

  3. Renal colic, where is it headed? An observational study

    Directory of Open Access Journals (Sweden)

    Paolo Beltrami

    2016-03-01

    Full Text Available Aim: In the last thirty years, the treatment for renal and ureteral calculi has undergone profound variations. The objective of this study has been to evaluate the existence of parameters which can affect the spontaneous expulsion of a symptomatic ureteral stone in a reasonably brief period of time and to identify whether certain parameters such as sex, age, the location and dimension of the stone, the presence of dilation in the urinary tract together with the administered therapy, can be used for a correct clinical management of the patient. Methods: In a period of 9 months, 486 cases of renal colic were registered at emergency department. Results: The cases of renal colic due to ureteral calculus were 188 (38.7%. The patients’ charts, complete of all data and therefore, valid for this research, resulted to be 120 (64%. In the presence of a symptomatic ureteral stone, the correct approach must first of all, focalize on the dimension of the calculus itself; less importance instead, is given to the location, as reported in other studies, the presence of hydroureteronephrosis, sex and the side. Conclusion: In the cases when the pain symptoms cannot be solved by means of the administration of analgesics, it is then reasonable to take into consideration an immediate endourological treatment. If the pain symptoms are promptly solved, an attentive wait of 4 weeks should be considered reasonable in order to allow spontaneous expulsion of the calculus.

  4. Change in neck circumference after shoulder arthroscopy: An observational study

    Directory of Open Access Journals (Sweden)

    Shrividya Chellam

    2015-01-01

    Full Text Available Background and Aims: Shoulder arthroscopy requires fluid irrigation, which causes soft-tissue oedema around chest, neck, and arm intraoperatively, leading to postoperative airway complications. We decided to study the incidence of increase in the neck circumference in shoulder arthroscopy and its effects on the airway. Methods: We studied 32 cases of shoulder arthroscopies over a period of 1-year, performed under general anaesthesia with interscalene block. The neck circumference of patients before and after the procedure was measured along with other parameters. The endotracheal tube cuff was deflated at the end of surgery to determine air leak around the tube. The negative leak test suggested airway oedema. Results: Thirty out of 32 patients showed positive air leak test. The average change in neck circumference was 1.17 ± 1.16 cm and all could be extubated uneventfully. Two showed negative leak test with an increase in neck circumference by 4.5 and 6.4 cm and were not extubated. Multiple regression analysis for risk factors showed intraoperative hypertension as a single predictor for an increase in neck circumference. Conclusion: Change in the neck circumference beyond 4 cm may suggest airway compromise and below 4 cm, airway compromise is unlikely even in the presence of extensive soft-tissue oedema around the shoulder, upper arm and chest.

  5. An observational study on extraperitoneal caesarean section in present era

    Directory of Open Access Journals (Sweden)

    Sudhanshu Sekhara Nanda

    2014-06-01

    Full Text Available Background: This study was designed to find out the maternal and perinatal outcome in cases of extraperitoneal caesarean section. Total 100 women undergoing extraperitoneal cesarean section were included in the study. Methods: A detailed history taking, examination done and intra and post-operative parameters as per protocols were noted. Results: Success rate of extra peritoneal CS was 79.63%, Time taken from incision to delivery was and #8804;5 minutes in 60% cases, time taken from incision to closure was between 31-45 min in 67% cases, blood loss and #8804;500 ml in 58% cases, return of bowel function between 5-8 hours in 52%, mobilization within 24 hours in 52%, neonatal one minute APGAR score and #8805;7 in 90.91%. Conclusions: Extraperitoneal cesarean section can be applied as a surgical form of infection prophylaxis. Since it possesses a rational basis for the avoidance of serious post-operative pelvic infectious complications, this operation deserves reconsideration in the modern era. [Int J Reprod Contracept Obstet Gynecol 2014; 3(3.000: 724-727

  6. Ground-based Infrared Observations of Water Vapor and Hydrogen Peroxide in the Atmosphere of Mars

    Science.gov (United States)

    Encrenaz, T.; Greathouse, T. K.; Bitner, M.; Kruger, A.; Richter, M. J.; Lacy, J. H.; Bézard, B.; Fouchet, T.; Lefevre, F.; Forget, F.; Atreya, S. K.

    2008-11-01

    Ground-based observations of water vapor and hydrogen peroxide have been obtained in the thermal infrared range, using the TEXES instrument at the NASA Infrared Telescope Facility, for different times of the seasonal cycle.

  7. GNSS-based Observations and Simulations of Spectral Scintillation Indices in the Arctic Ionosphere

    DEFF Research Database (Denmark)

    Durgonics, Tibor; Hoeg, Per; von Benzon, Hans-Henrik;

    During disturbed times, ionospheric scintillations can be severe and adversely impact satellite-based positioning and radio transmissions. The scintillation occurs in the amplitude, phase, polarization, and angle of arrival of the signal. Precise observation, classification, modeling, forecasting...

  8. THE MANY FACES OF PNEUMOMEDIASTINUM: AN OBSERVATIONAL STUDY

    Directory of Open Access Journals (Sweden)

    Narendra Kumar Narahari

    2016-06-01

    Full Text Available Pneumomediastinum is an uncommon condition which is defined by the presence of air in the mediastinum. It may result from a number of causes, but at times the underlying aetiology remains obscure. The present study aims to review the clinical and imaging features in patients who presented with pneumomediastinum alone or in association with other findings in order to establish the aetiological diagnosis. We report here, a series of cases with pneumomediastinum of various unusual aetiologies and also the clinical profile, predisposing factors and outcome of these patients along with the associated complications. METHODS We retrospectively reviewed the records of all patients who presented to the respiratory unit of our hospital with the diagnosis of pneumomediastinum over a period of 2 years from 2013-2015. The cases of pneumomediastinum resulting from trauma and iatrogenic causes were excluded from the study. RESULTS A total of six patients (4 males and 2 females with pneumomediastinum were identified during the study period after applying the exclusion criteria. The most common presenting symptom in these cases was shortness of breath followed by dry cough, chest pain and fever. Subcutaneous emphysema and Hamman sign was identified in one patient each. Of the six cases, preexisting lung disease was identified in 3 patients and these included connective tissue disease related interstitial lung disease in two cases and combined pulmonary fibrosis and emphysema in one case. In the remaining three cases, the causes of pneumomediastinum were Pneumocystis carinii pneumonia (PCP in HIV positive patient, pulmonary tuberculosis in another and spontaneous oesophageal perforation in the third. Coexisting pneumothorax was present in 3 out of 6 cases. The mean duration of hospital stay in these six patients was 8 days. No recurrence of pneumomediastinum was seen in any of the six patients during six months of followup. CONCLUSIONS Pneumomediastinum is a

  9. Can headache impair intellectual abilities in children? An observational study

    Directory of Open Access Journals (Sweden)

    Esposito M

    2012-11-01

    Full Text Available Maria Esposito,1 Antonio Pascotto,1 Beatrice Gallai,3 Lucia Parisi,2 Michele Roccella,2 Rosa Marotta,4 Serena Marianna Lavano,4 Antonella Gritti,5 Giovanni Mazzotta,6 Marco Carotenuto11Center for Childhood Headache, Clinic of Child and Adolescent Neuropsychiatry, Second University of Naples, Naples, 2Child Neuropsychiatry, Department of Psychology, University of Palermo, Palermo, 3Unit of Child and Adolescent Neuropsychiatry, University of Perugia, Perugia, 4Department of Psychiatry, “Magna Graecia” University of Catanzaro, Catanzaro, 5Suor Orsola Benincasa University, Napoli, 6Unit of Child and Adolescent Neuropsychiatry, Azienda Sanitaria Locale 4, Terni, ItalyBackground: The purpose of this study was to assess the cognitive functioning of children affected by headache, pinpointing the differences in intelligence style between subjects affected by migraine without aura and subjects with tension-type headache.Methods: The study population consisted of 147 children (mean age 10.82 ± 2.17 years with headache, recruited from the Headache Center for Developmental Age, Child and Adolescent Neuropsychiatry Clinic, Second University of Naples. Cognitive profiling was performed using Weschler Intelligence Scale for Children Third Edition throughout the sample. According to the International Classification of Headache Disorders II criteria for pediatric age, subjects were divided into a migraine without aura group (n = 75; 43 boys, 32 girls and a tension-type headache group (n = 72; 49 boys, 23 girls. The results were compared with the findings obtained from a sample of 137 healthy control subjects recruited from schools in the Campania region, matched for age and gender.Results: No difference in full intelligence quotient was found between the groups, but the children with tension-type headache had a lower verbal intelligence quotient and a higher performance intelligence quotient than the healthy controls and children with migraine. Factor

  10. UFOs in the LHC: Observations, studies and extrapolations

    CERN Document Server

    Baer, T; Cerutti, F; Ferrari, A; Garrel, N; Goddard, B; Holzer, EB; Jackson, S; Lechner, A; Mertens, V; Misiowiec, M; Nebot del Busto, E; Nordt, A; Uythoven, J; Vlachoudis, V; Wenninger, J; Zamantzas, C; Zimmermann, F; Fuster, N

    2012-01-01

    Unidentified falling objects (UFOs) are potentially a major luminosity limitation for nominal LHC operation. They are presumably micrometer sized dust particles which lead to fast beam losses when they interact with the beam. With large-scale increases and optimizations of the beam loss monitor (BLM) thresholds, their impact on LHC availability was mitigated from mid 2011 onwards. For higher beam energy and lower magnet quench limits, the problem is expected to be considerably worse, though. In 2011/12, the diagnostics for UFO events were significantly improved: dedicated experiments and measurements in the LHC and in the laboratory were made and complemented by FLUKA simulations and theoretical studies. The state of knowledge, extrapolations for nominal LHC operation and mitigation strategies are presented

  11. Skin features in myotonic dystrophy type 1: an observational study.

    Science.gov (United States)

    Campanati, A; Giannoni, M; Buratti, L; Cagnetti, C; Giuliodori, K; Ganzetti, G; Silvestrini, M; Provinciali, L; Offidani, A

    2015-05-01

    Poor data regarding skin involvement in Myotonic Dystrophy, also named Dystrophia Myotonica type 1, have been reported. This study aimed to investigate the prevalence and types of skin disorders in adult patients with Myotonic Dystrophy type 1. Fifty-five patients and one hundred age- and sex-matched healthy subjects were referred to a trained dermatologist for a complete skin examination to check for potential cutaneous hallmarks of disease. No difference in prevalence of preneoplastic, neoplastic, and cutaneous lesions was detected between the two groups. Among morphofunctional, proliferative and inflammatory lesions, focal hyperhidrosis (p Myotonic Dystrophy type 1 significant differences according to sex were found for: early androgenic alopecia, twisted hair and seborrheic dermatitis, whose prevalence was higher in males (p Myotonic Dystrophy type 1. On the other hand, an increased prevalence of morphofunctional, inflammatory, and proliferative diseases involving adnexal structures seems to characterize adult patients with Myotonic Dystrophy type 1.

  12. Fluoroquinolone resistance during 2000–2005 : An observational study

    Directory of Open Access Journals (Sweden)

    Sheehan Paul

    2008-05-01

    Full Text Available Abstract Background Moxifloxacin is a respiratory fluoroquinolone with a community acquired pneumonia indication. Unlike other fluoroquinolones used in our healthcare system, moxifloxacin's urinary excretion is low and thus we hypothesized that increased use of moxifloxacin is associated with an increase in fluoroquinolone resistance amongst gram negative uropathogens. Methods All antibiograms for Gram negative bacteria were obtained for 2000 to 2005. The defined daily dose (DDD for each fluoroquinolone was computed according to World Health Organization criteria. To account for fluctuation in patient volume, DDD/1000 bed days was computed for each year of study. Association between DDD/1000 bed days for each fluoroquinolone and the susceptibility of Gram negative bacteria to ciprofloxacin was assessed using Pearson's Correlation Coefficient, r. Results During the study period, there were 48,261 antibiograms, 347,931 DDD of fluoroquinolones, and 1,943,338 bed days. Use of fluoroquinolones among inpatients decreased from 237.2 DDD/1000 bed days in 2000 to 115.2 DDD/1000 bed days in 2005. With the exception of Enterobacter aerogenes, moxifloxacin use was negatively correlated with sensitivity among all 13 Gram negative species evaluated (r = -0.07 to -0.97. When the sensitivities of all Gram negative organisms were aggregated, all fluoroquinolones except moxifloxacin were associated with increased sensitivity (r = 0.486 to 1.000 while moxifloxacin was associated with decreased sensitivity (r = -0.464. Conclusion Moxifloxacin, while indicated for empiric treatment of community acquired pneumonia, may have important negative influence on local antibiotic sensitivities amongst Gram negative organisms. This effect was not shared by other commonly used members of the fluoroquinolone class.

  13. Robust H∞ Controller Design for Uncertain Neutral Systems via Dynamic Observer Based Output Feedback

    Institute of Scientific and Technical Information of China (English)

    Fatima El Haoussi; El (H)oussaine Tissir

    2009-01-01

    In this paper, the dynamic observer-based controller design for a class of neutral systems with H∞ control is considered. An observer-based output feedback is derived for systems with polytopic parameter uncertainties. This controller assures delay-dependent stabilization and H∞ norm bound attenuation from the disturbance input to the controllcd output. Numerical examples are provided for illustration and comparison of the proposed conditions.

  14. Evaluation of satellite soil moisture products over Norway using ground-based observations

    Science.gov (United States)

    Griesfeller, A.; Lahoz, W. A.; Jeu, R. A. M. de; Dorigo, W.; Haugen, L. E.; Svendby, T. M.; Wagner, W.

    2016-03-01

    In this study we evaluate satellite soil moisture products from the advanced SCATterometer (ASCAT) and the Advanced Microwave Scanning Radiometer - Earth Observing System (AMSR-E) over Norway using ground-based observations from the Norwegian water resources and energy directorate. The ASCAT data are produced using the change detection approach of Wagner et al. (1999), and the AMSR-E data are produced using the VUA-NASA algorithm (Owe et al., 2001, 2008). Although satellite and ground-based soil moisture data for Norway have been available for several years, hitherto, such an evaluation has not been performed. This is partly because satellite measurements of soil moisture over Norway are complicated owing to the presence of snow, ice, water bodies, orography, rocks, and a very high coastline-to-area ratio. This work extends the European areas over which satellite soil moisture is validated to the Nordic regions. Owing to the challenging conditions for soil moisture measurements over Norway, the work described in this paper provides a stringent test of the capabilities of satellite sensors to measure soil moisture remotely. We show that the satellite and in situ data agree well, with averaged correlation (R) values of 0.72 and 0.68 for ASCAT descending and ascending data vs in situ data, and 0.64 and 0.52 for AMSR-E descending and ascending data vs in situ data for the summer/autumn season (1 June-15 October), over a period of 3 years (2009-2011). This level of agreement indicates that, generally, the ASCAT and AMSR-E soil moisture products over Norway have high quality, and would be useful for various applications, including land surface monitoring, weather forecasting, hydrological modelling, and climate studies. The increasing emphasis on coupled approaches to study the earth system, including the interactions between the land surface and the atmosphere, will benefit from the availability of validated and improved soil moisture satellite datasets, including those

  15. Speech-based recognition of self-reported and observed emotion in a dimensional space

    NARCIS (Netherlands)

    Truong, Khiet P.; Leeuwen, van David A.; Jong, de Franciska M.G.

    2012-01-01

    The differences between self-reported and observed emotion have only marginally been investigated in the context of speech-based automatic emotion recognition. We address this issue by comparing self-reported emotion ratings to observed emotion ratings and look at how differences between these two t

  16. Fault Diagnosis of an Advanced Wind Turbine Benchmark using Interval-based ARRs and Observers

    DEFF Research Database (Denmark)

    Sardi, Hector Eloy Sanchez; Escobet, Teressa; Puig, Vicenc;

    2015-01-01

    This paper proposes a model-based fault diagnosis (FD) approach for wind turbines and its application to a realistic wind turbine FD benchmark. The proposed FD approach combines the use of analytical redundancy relations (ARRs) and interval observers. Interval observers consider an unknown...

  17. Adverse effect profile of trichlormethiazide: a retrospective observational study

    Directory of Open Access Journals (Sweden)

    Nishida Yayoi

    2011-05-01

    Full Text Available Abstract Background Trichlormethiazide, a thiazide diuretic, was introduced in 1960 and remains one of the most frequently used diuretics for treating hypertension in Japan. While numerous clinical trials have indicated important side effects of thiazides, e.g., adverse effects on electrolytes and uric acid, very few data exist on serum electrolyte levels in patients with trichlormethiazide treatment. We performed a retrospective cohort study to assess the adverse effects of trichlormethiazide, focusing on serum electrolyte and uric acid levels. Methods We used data from the Clinical Data Warehouse of Nihon University School of Medicine obtained between Nov 1, 2004 and July 31, 2010, to identify cohorts of new trichlormethiazide users (n = 99 for 1 mg, n = 61 for 2 mg daily dosage and an equal number of non-users (control. We used propensity-score matching to adjust for differences between users and control for each dosage, and compared serum chemical data including serum sodium, potassium, uric acid, creatinine and urea nitrogen. The mean exposure of trichlormethiazide of 1 mg and 2 mg users was 58 days and 64 days, respectively. Results The mean age was 66 years, and 55% of trichlormethiazide users of the 1 mg dose were female. In trichlormethiazide users of the 2 mg dose, the mean age was 68 years, and 43% of users were female. There were no statistically significant differences in all covariates (age, sex, comorbid diseases, past drugs, and current antihypertensive drugs between trichlormethiazide users and controls for both doses. In trichlormethiazide users of the 2 mg dose, the reduction of serum potassium level and the elevation of serum uric acid level were significant compared with control, whereas changes of mean serum sodium, creatinine and urea nitrogen levels were not significant. In trichlormethiazide users of the 1 mg dose, all tests showed no statistically significant change from baseline to during the exposure period in

  18. Metaphors among titles of medical publications: an observational study

    Directory of Open Access Journals (Sweden)

    Philippa Mungra

    2007-10-01

    Full Text Available In this study, we attempted to determine the frequency and types of metaphors in a corpus of titles from a single medical journal collected over one year. The frequency of metaphor tokens (4.6% was highest among editorials and other opinion articles and consisted predominantly of primary metaphors, which require explanation using a visual, cultural or other physical vehicle. When the metaphor was used only in the title and not in the body of the text, as was common in letters to the editor or in editorials, the metaphor may constitute a para-textual device used for engaging the reader. Other metaphors among research article titles were present not only in the title, but also used repeatedly in the body of the text. Among these research articles, metaphors were frequently used to endow the focus words of the metaphor with a precise and meaningful significance which, when used repeatedly in the text, may constitute a mechanism by which sub-technical language or internal jargon may arise. Being syntactically simple but endowed with a high communicative import, titles as a text type may help improve academic literacy, among beginners.

  19. An observational study of alemtuzumab following fingolimod for multiple sclerosis

    Science.gov (United States)

    Willis, Mark; Pearson, Owen; Illes, Zsolt; Sejbaek, Tobias; Nielsen, Christian; Duddy, Martin; Petheram, Kate; van Munster, Caspar; Killestein, Joep; Malmeström, Clas; Tallantyre, Emma

    2017-01-01

    Objective: To describe a series of patients with relapsing multiple sclerosis (MS) who experienced significant and unexpected disease activity within the first 12 months after switching from fingolimod to alemtuzumab. Methods: Patients with relapsing MS treated sequentially with fingolimod then alemtuzumab who experienced significant subsequent disease activity were identified by personal communication with 6 different European neuroscience centers. Results: Nine patients were identified. Median disease duration to alemtuzumab treatment was 94 (39–215) months and follow-up from time of first alemtuzumab cycle 20 (14–21) months. Following first alemtuzumab infusion cycle, 8 patients were identified by at least 1 clinical relapse and radiologic disease activity and 1 by significant radiologic disease activity alone. Conclusions: We acknowledge the potential for ascertainment bias; however, these cases may illustrate an important cause of reduced efficacy of alemtuzumab in a vulnerable group of patients with MS most in need of disease control. We suggest that significant and unexpected subsequent disease activity after alemtuzumab induction results from prolonged sequestration of autoreactive lymphocytes following fingolimod withdrawal, allowing these cells to be concealed from the usual biological effect of alemtuzumab. Subsequent lymphocyte egress then provokes disease reactivation. Further animal studies and clinical trials are required to confirm these phenomena and in the meantime careful consideration should be given to mode of action of individual therapies and sequential treatment effects in MS when designing personalized treatment regimens. PMID:28101520

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

    Directory of Open Access Journals (Sweden)

    Beerstecher Hendrik J

    2010-06-01

    Full Text Available Abstract 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.

  1. Endotoxin Elimination in Patients with Septic Shock: An Observation Study.

    Science.gov (United States)

    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.

  2. Aortic replacement in aorto-occlusive disease: an observational study

    Directory of Open Access Journals (Sweden)

    Winter Richard K

    2008-10-01

    Full Text Available Abstract Background For many patients with aorto-occlusive disease, where stent deployment is not possible, surgery remains the only treatment option available. The aim of this study was to assess the results of aortic reconstruction surgery performed in patients with critical ischaemia. Methods All patients with critical ischaemia undergoing surgery during 1991–2004 were identified from a prospectively maintained database. Mortality data was verified against death certificate data. Demographic and clinical data were obtained from the clinical notes and the radiology database. Disease was classified as: type I – limited to aorta and common iliac arteries; type II – external iliac disease and type III combined aortic, iliac and infra-inguinal disease. Results 86 patients underwent aortic replacement surgery all of whom had critical ischaemia consisting of: type I (n = 16; type II (n = 37 and type III (n = 33. The 30-day mortality rate was 10.4%, the one-year patient survival was 80%, and the 1-year graft survival was 80%. At 2 years the actual patient survival was 73% and no additional graft losses were identified. All patients surviving 30 days reported excellent symptomatic relief. Early, complications occurred in 6 (7% patients: thrombosis within diseased superficial femoral arteries (n = 4; haemorrhage and subsequent death (n = 2. Ten (14% late complications (> 12 months occurred in the 69 surviving patients and included: anastomotic stenosis (n = 3; graft thrombosis (n = 4, graft infection (n = 3. Four patients developed claudication as a result of more distal disease in the presence of a patent graft, and 1 patient who continued smoking required an amputation for progressive distal disease. Conclusion Aortic reconstruction for patients with extensive aorto-occlussive disease provides long-standing symptomatic relief for the majority of patients. After the first year, there is continued patient attrition due to co

  3. Responses of the human motor system to observing actions across species: A transcranial magnetic stimulation study.

    Science.gov (United States)

    White, Nicole C; Reid, Connor; Welsh, Timothy N

    2014-10-22

    Ample evidence suggests that the role of the mirror neuron system (MNS) in monkeys is to represent the meaning of actions. The MNS becomes active in monkeys during execution, observation, and auditory experience of meaningful, object-oriented actions, suggesting that these cells represent the same action based on a variety of cues. The present study sought to determine whether the human motor system, part of the putative human MNS, similarly represents and reflects the meaning of actions rather than simply the mechanics of the actions. To this end, transcranial magnetic stimulation (TMS) of primary motor cortex was used to generate motor-evoked potentials (MEPs) from muscles involved in grasping while participants viewed object-oriented grasping actions performed by either a human, an elephant, a rat, or a body-less robotic arm. The analysis of MEP amplitudes suggested that activity in primary motor cortex during action observation was greatest during observation of the grasping actions of the rat and elephant, and smallest for the human and robotic arm. Based on these data, we conclude that the human action observation system can represent actions executed by non-human animals and shows sensitivity to species-specific differences in action mechanics.

  4. Space-based observations of fire NOx emission coefficients: a global biome-scale comparison

    Directory of Open Access Journals (Sweden)

    A. K. Mebust

    2013-08-01

    Full Text Available Biomass burning represents both a significant and highly variable source of NOx to the atmosphere. This variability stems from both the episodic nature of fires, and from fire conditions such as the modified combustion efficiency of the fire, the nitrogen content of the fuel and possibly other factors that have not been identified or evaluated by comparison with observations. Satellite instruments offer an opportunity to observe emissions from wildfires, providing a large suite of measurements which allow us to study mean behavior and variability on the regional scale in a statistically rigorous manner. Here we use space-based measurements of fire radiative power from the Moderate Resolution Imaging Spectroradiometer in combination with NO2 tropospheric column densities from the Ozone Monitoring Instrument to measure mean emission coefficients (ECs in g NO MJ−1 from fires for global biomes, and across a wide range of smaller-scale ecoregions, defined as spatially-distinct clusters of fires with similar fuel type. Mean ECs for all biomes fall between 0.250–0.362 g NO MJ−1, a range that is smaller than found in previous studies of biome-scale emission factors. The majority of ecoregion ECs fall within or near this range, implying that under most conditions, mean fire emissions per unit energy are similar between different regions regardless of fuel type or spatial variability. In contrast to these similarities, we find that about 24% of individual ecoregion ECs deviate significantly (p x emissions.

  5. Precipitation and microphysical processes observed by three polarimetric X-band radars and ground-based instrumentation during HOPE

    OpenAIRE

    Xie, Xinxin; Evaristo, Raquel; Simmer, Clemens; Handwerker, Jan; Trömel, Silke

    2016-01-01

    This study presents a first analysis of precipitation and related microphysical processes observed by three polarimetric X-band Doppler radars (BoXPol, JuXPol and KiXPol) in conjunction with a ground-based network of disdrometers, rain gauges and vertically pointing micro rain radars (MRRs) during the High Definition Clouds and Precipitation for advancing Climate Prediction (HD(CP)2) Observational Prototype Experiment (HOPE) during April and May 2013 in Germany. While JuXPol...

  6. Towards retrieving critical relative humidity from ground-based remote sensing observations

    Energy Technology Data Exchange (ETDEWEB)

    Van Weverberg, Kwinten; Boutle, Ian; Morcrette, Cyril J.; Newsom, Rob K.

    2016-08-22

    Nearly all parameterisations of large-scale cloud require the specification of the critical relative humidity (RHcrit). This is the gridbox-mean relative humidity at which the subgrid fluctuations in temperature and water vapour become so large that part of a subsaturated gridbox becomes saturated and cloud starts to form. Until recently, the lack of high-resolution observations of temperature and moisture variability has hindered a reasonable estimate of the RHcrit from observations. However, with the advent of ground-based measurements from Raman lidar, it becomes possible to obtain long records of temperature and moisture (co-)variances with sub-minute sample rates. Lidar observations are inherently noisy and any analysis of higher-order moments will be very dependent on the ability to quantify and remove this noise. We present an exporatory study aimed at understanding whether current noise levels of lidar-retrieved temperature and water vapour are sufficient to obtain a reasonable estimate of the RHcrit. We show that vertical profiles of RHcrit can be derived for a gridbox length of up to about 30 km (120) with an uncertainty of about 4 % (2 %). RHcrit tends to be smallest near the scale height and seems to be fairly insensitive to the horizontal grid spacing at the scales investigated here (30 - 120 km). However, larger sensitivity was found to the vertical grid spacing. As the grid spacing decreases from 400 to 100 m, RHcrit is observed to increase by about 6 %, which is more than the uncertainty in the RHcrit retrievals.

  7. Dust forecast over North Africa: verification with satellite and ground based observations

    Science.gov (United States)

    Singh, Aditi; Kumar, Sumit; George, John P.

    2016-05-01

    Arid regions of North Africa are considered as one of the major dust source. Present study focuses on the forecast of aerosol optical depth (AOD) of dust over different regions of North Africa. NCMRWF Unified Model (NCUM) produces dust AOD forecasts at different wavelengths with lead time upto 240 hr, based on 00UTC initial conditions. Model forecast of dust AOD at 550 nm up to 72 hr forecast, based on different initial conditions are verified against satellite and ground based observations of total AOD during May-June 2014 with the assumption that except dust, presence of all other aerosols type are negligible. Location specific and geographical distribution of dust AOD forecast is verified against Aerosol Robotic Network (AERONET) station observations of total and coarse mode AOD. Moderate Resolution Imaging Spectroradiometer (MODIS) dark target and deep blue merged level 3 total aerosol optical depth (AOD) at 550 nm and Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) retrieved dust AOD at 532 nm are also used for verification. CALIOP dust AOD was obtained by vertical integration of aerosol extinction coefficient at 532 nm from the aerosol profile level 2 products. It is found that at all the selected AERONET stations, the trend in dust AODs is well predicted by NCUM up to three days advance. Good correlation, with consistently low bias (~ +/-0.06) and RMSE (~ 0.2) values, is found between model forecasts and point measurements of AERONET, except over one location Cinzana (Mali). Model forecast consistently overestimated the dust AOD compared to CALIOP dust AOD, with a bias of 0.25 and RMSE of 0.40.

  8. Dynamic neural network-based robust observers for uncertain nonlinear systems.

    Science.gov (United States)

    Dinh, H T; Kamalapurkar, R; Bhasin, S; Dixon, W E

    2014-12-01

    A dynamic neural network (DNN) based robust observer for uncertain nonlinear systems is developed. The observer structure consists of a DNN to estimate the system dynamics on-line, a dynamic filter to estimate the unmeasurable state and a sliding mode feedback term to account for modeling errors and exogenous disturbances. The observed states are proven to asymptotically converge to the system states of high-order uncertain nonlinear systems through Lyapunov-based analysis. Simulations and experiments on a two-link robot manipulator are performed to show the effectiveness of the proposed method in comparison to several other state estimation methods.

  9. First ground-based FTIR-observations of methane in the tropics

    Directory of Open Access Journals (Sweden)

    A. K. Petersen

    2010-02-01

    Full Text Available Total column concentrations and volume mixing ratio profiles of methane have been retrieved from ground-based solar absorption FTIR spectra in the near-infrared recorded in Paramaribo (Suriname. The methane FTIR observations are compared with TM5 model simulations and satellite observations from SCIAMACHY, and represent the first validation of SCIAMACHY retrievals in the tropics using ground-based remote sensing techniques. Apart from local biomass burning features, our methane FTIR observations agree well with the SCIAMACHY retrievals and TM5 model simulations.

  10. Observer-based passive control for descriptor systems with time-delay

    Institute of Scientific and Technical Information of China (English)

    Li Qin; Zhang Qingling; Zhang Yanjuan; An Yichun

    2009-01-01

    This article is concerned with the problem of observer-based passive control for descriptor systems with time delay. Sufficient conditions are first presented for the closed loop systems to be admissible and passive with dissipation ηin the case of that the time delay is known, and two kinds of methods are given to design the expected observer. Then, the case of that the time delay is unknown or uncertain is discussed. The observer-based control gains could be obtained from the solutions of linear matrix inequalities (LMIs). Simulation examples are given to show the effectiveness of the designed methods.

  11. Using web-based observations to identify thresholds of a person's stability in a flow

    Science.gov (United States)

    Milanesi, L.; Pilotti, M.; Bacchi, B.

    2016-10-01

    Flood risk assessment and mitigation are important tasks that should take advantage of rational vulnerability models to increase their effectiveness. These models are usually identified through a relevant set of laboratory experiments. However, there is growing evidence that these tests are not fully representative of the variety of conditions that characterize real flood hazard situations. This paper suggests a citizen science-based and innovative approach to obtain information from web resources for the calibration of people's vulnerability models. A comprehensive study employing commonly used web engines allowed the collection of a wide set of documents showing real risk situations for people impacted by floods, classified according to the stability of the involved subjects. A procedure to extrapolate the flow depth and velocity from the video frames is developed and its reliability is verified by comparing the results with observation. The procedure is based on the statistical distribution of the population height employing a direct uncertainty propagation method. The results complement the experimental literature data and conceptual models. The growing availability of online information will progressively increase the sample size on which the procedure is based and will eventually lead to the identification of a probability surface describing the transition between stability and instability conditions of individuals in a flow.

  12. Towards a radar- and observation-based hail climatology for Germany

    Directory of Open Access Journals (Sweden)

    Thomas Junghänel

    2016-09-01

    Full Text Available In the German Strategy for Adaptation to Climate Change hail is identified as one of the major subjects of concern regarding transport infrastructure. Moreover hailstorms are a major threat to e.g. agriculture and the automobile industry causing significant economical damages and losses. Despite these significant hail-related meteorological risks no comprehensive observation-based hail climatology for Germany exists. In this study we present a new approach to this task, combining radar data with different kinds of hail reports, such as ground observation and agricultural insurance data. Preprocessing ensures the applicability of the radar data for the presented climatological analysis. In this sense a number of detection methods are applied to filter artefacts, especially clutter pixels and spokes that disrupt radar measurements. To construct a reliable hail climatology for Germany we process all information into a 10‑year based annual average number of hail days on a 1km×1km$1\\,\\text{km}\\times1\\,\\text{km}$ grid using a two-path hail criterion. While the first path combines a threshold of 50 dBZ with a hail report, the second path is based on a 55 dBZ threshold only. By adding radar data we increase the spatial representativity of the ground based hail reports and gain additional information in regions which lack observational data. Overall, the results are mainly determined by events derived from the first path (68 %. A validation of our dataset at 65 stations of Deutscher Wetterdienst shows that the method slightly underestimates the number of hail days, especially for mountainous regions. This results in a better adaption of the hail criterion to lowlands. The resulting hail frequency map shows an increase in the average number of hail days per year from north to south. In particular, hailstorms occur less frequently in the Central North German Plain and the Mecklenburg Coastal Lowland, whereas the highest number of hail days

  13. ORPOM model for optimum distribution of tree ring sampling based on the climate observation network

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Tree ring dating plays an important role in obtaining past climate information.The fundamental study of obtaining tree ring samples in typical climate regions is particularly essential.The optimum distribution of tree ring sampling sites based on climate information from the Climate Observation Network(ORPOM model) is presented in this article.In this setup,the tree rings in a typical region are used for surface representation,by applying excellent correlation with the climate information as the main principle.Taking the Horqin Sandy Land in the cold and arid region of China as an example,the optimum distribution range of the tree ring sampling sites was obtained through the application of the ORPOM model,which is considered a reasonably practical scheme.

  14. Studies of Arctic Tropospheric Ozone Depletion Events Through Buoy-Borne Observations and Laboratory Studies

    Science.gov (United States)

    Halfacre, John W.

    The photochemically-induced destruction of ground-level Arctic ozone in the Arctic occurs at the onset of spring, in concert with polar sunrise. Solar radiation is believed to stimulate a series of reactions that cause the production and release of molecular halogens from frozen, salty surfaces, though this mechanism is not yet well understood. The subsequent photolysis of molecular halogens produces reactive halogen atoms that remove ozone from the atmosphere in these so-called "Ozone Depletion Events" (ODEs). Given that much of the Arctic region is sunlit, meteorologically stable, and covered by saline ice and snow, it is expected that ODEs could be a phenomenon that occurs across the entire Arctic region. Indeed, an ever-growing body of evidence from coastal sites indicates that Arctic air masses devoid of O3 most often pass over sea ice-covered regions before arriving at an observation site, suggesting ODE chemistry occurs upwind over the frozen Arctic Ocean. However, outside of coastal observations, there exist very few long-term observations from the Arctic Ocean from which quantitative assessments of basic ODE characteristics can be made. This work presents the interpretation of ODEs through unique chemical and meteorological observations from several ice-tethered buoys deployed around the Arctic Ocean. These observations include detection of ozone, bromine monoxide, and measurements of temperature, relative humidity, atmospheric pressure, wind speed, and wind direction. To assess whether the O-Buoys were observing locally based depletion chemistry or the transport of ozone-poor air masses, periods of ozone decay were interpreted based on current understanding of ozone depletion kinetics, which are believed to follow a pseudo-first order rate law. In addition, the spatial extents of ODEs were estimated using air mass trajectory modeling to assess whether they are a localized or synoptic phenomenon. Results indicate that current understanding of the

  15. Vitamin K status and vascular calcification: evidence from observational and clinical studies.

    Science.gov (United States)

    Shea, M Kyla; Holden, Rachel M

    2012-03-01

    Vascular calcification occurs when calcium accumulates in the intima (associated with atherosclerosis) and/or media layers of the vessel wall. Coronary artery calcification (CAC) reflects the calcium burden within the intima and media of the coronary arteries. In population-based studies, CAC independently predicts cardiovascular disease (CVD) and mortality. A preventive role for vitamin K in vascular calcification has been proposed based on its role in activating matrix Gla protein (MGP), a calcification inhibitor that is expressed in vascular tissue. Although animal and in vitro data support this role of vitamin K, overall data from human studies are inconsistent. The majority of population-based studies have relied on vitamin K intake to measure status. Phylloquinone is the primary dietary form of vitamin K and available supplementation trials, albeit limited, suggest phylloquinone supplementation is relevant to CAC. Yet observational studies have found higher dietary menaquinone, but not phylloquinone, to be associated with less calcification. Vascular calcification is highly prevalent in certain patient populations, especially in those with chronic kidney disease (CKD), and it is plausible vitamin K may contribute to reducing vascular calcification in patients at higher risk. Subclinical vitamin K deficiency has been reported in CKD patients, but studies linking vitamin K status to calcification outcomes in CKD are needed to clarify whether or not improving vitamin K status is associated with improved vascular health in CKD. This review summarizes the available evidence of vitamin K and vascular calcification in population-based studies and clinic-based studies, with a specific focus on CKD patients.

  16. Introducing peer observation of teaching to GP teachers: a questionnaire study.

    Science.gov (United States)

    Adshead, Lesley; White, Patrick T; Stephenson, Anne

    2006-03-01

    In medical education programmes which rely on clinical teachers spread across diverse sites, the application of peer observation of teaching offers the potential of both supporting teachers and maintaining quality. This paper reports on a questionnaire survey carried out with general practitioner (GP) teachers of medical undergraduate students from King's College London School of Medicine at Guy's, King's College and St Thomas' Hospitals. The aim of the study was to determine GP teachers' views on a proposed programme of peer observation of their teaching. The majority of GP teachers identified benefits of the proposed scheme with 69% saying it would help improve the education of future doctors. However, despite seeing the benefits, less than half wished to take part in the programme. Two thirds cited time and paperwork as major disincentives to taking part and 62% said that they felt it would make them feel under scrutiny. No associations were found between measures of workload and willingness to take part. This suggests that a fundamental fear of scrutiny and criticism may be the main hurdle to be overcome in implementing the scheme. Imposing peer observation on GP teachers in the form proposed could create suspicion and distance between the university department and practice-based GP teachers and may even result in a loss of teachers. The introduction of peer observation is more likely to be successful if GPs' apprehensions are addressed. Using peer observation to strengthen the process of quality assurance may undermine its role in the support and development of clinical teachers.

  17. Interplanetary Charged Dust Magnetic Clouds Striking the Magnetosphere: Coordinated Space-based and Ground-based Observations

    Science.gov (United States)

    Russell, C. T.; Chi, Peter; Lai, Hairong

    In general, asteroids, meteoroids and dust do not interact with the plasma structures in the solar system, but after a collision between fast moving bodies the debris cloud contains nanoscale dust particles that are charged and behave like heavy ions. Dusty magnetic clouds are then accelerated to the solar wind speed. While they pose no threat to spacecraft because of the particle size, the coherency imposed by the magnetization of the cloud allows the cloud to interact with the Earth’s magnetosphere as well as the plasma in the immediate vicinity of the cloud. We call these clouds Interplanetary Field Enhancements (IFEs). These IFEs are a unique class of interplanetary field structures that feature cusp-shaped increases and decreases in the interplanetary magnetic field and a thin current sheet. The occurrence of IFEs is attributed to the interaction between the solar wind and dust particles produced in inter-bolide collisions. Previous spacecraft observations have confirmed that IFEs move with the solar wind. When IFEs strike the magnetosphere, they may distort the magnetosphere in several possible ways, such as producing a small indentation, a large scale compression, or a glancing blow. In any event if the IFE is slowed by the magnetosphere, the compression of the Earth’s field should be seen in the ground-based magnetic records that are continuously recorded. Thus it is important to understand the magnetospheric response to IFE arrival. In this study, we investigate the IFE structure observed by spacecraft upstream of the magnetosphere and the induced magnetic field perturbations observed by networks of ground magnetometers, including the THEMIS, CARISMA, McMAC arrays in North America and the IMAGE array in Europe. We find that, in a well-observed IFE event on December 24, 2006, all ground magnetometer stations observed an impulse at approximately 1217 UT when the IFE was expected to arrive at the Earth’s magnetopause. These ground stations spread across

  18. Poor quality of reporting confounding bias in observational intervention studies : a systematic review

    NARCIS (Netherlands)

    Groenwold, Rolf H H; Van Deursen, Anna M M; Hoes, Arno W; Hak, Eelko

    2008-01-01

    PURPOSE: To systematically review observational studies on medical interventions to determine the quality of reporting of confounding. METHODS: Articles on observational studies on medical interventions in five general medical journals and five epidemiological journals published between January 2004

  19. Classic (Nonquantic Algorithm for Observations and Measurements Based on Statistical Strategies of Particles Fields

    Directory of Open Access Journals (Sweden)

    D. Savastru

    2013-01-01

    Full Text Available Our knowledge about surroundings can be achieved by observations and measurements but both are influenced by errors (noise. Therefore one of the first tasks is to try to eliminate the noise by constructing instruments with high accuracy. But any real observed and measured system is characterized by natural limits due to the deterministic nature of the measured information. The present work is dedicated to the identification of these limits. We have analyzed some algorithms for selection and estimation based on statistical hypothesis and we have developed a theoretical method for their validation. A classic (non-quantic algorithm for observations and measurements based on statistical strategies of optical field is presented in detail. A generalized statistical strategy for observations and measurements on the nuclear particles, is based on these results, taking into account the particular type of statistics resulting from the measuring process also.

  20. Biomass burning emissions estimated with a global fire assimilation system based on observed fire radiative power

    Directory of Open Access Journals (Sweden)

    J. W. Kaiser

    2011-07-01

    Full Text Available The Global Fire Assimilation System (GFASv1.0 calculates biomass burning emissions by assimilating Fire Radiative Power (FRP observations from the MODIS instruments onboard the Terra and Aqua satellites. It corrects for gaps in the observations, which are mostly due to cloud cover, and filters spurious FRP observations of volcanoes, gas flares and other industrial activity. The combustion rate is subsequently calculated with land cover-specific conversion factors. Emission factors for 40 gas-phase and aerosol trace species have been compiled from a literature survey. The corresponding daily emissions have been calculated on a global 0.5° × 0.5° grid from 2003 to the present. General consistency with the Global Fire Emission Database version 3.1 (GFED3.1 within its accuracy is achieved while maintaining the advantages of an FRP-based approach: GFASv1.0 makes use of the quantitative information on the combustion rate that is contained in the observations, and it detects fires in real time at high spatial and temporal resolution. GFASv1.0 indicates omission errors in GFED3.1 due to undetected small fires. It also exhibits slightly longer fire seasons in South America and North Africa and a slightly shorter fire season in Southeast Asia. GFASv1.0 has already been used for atmospheric reactive gas simulations in an independent study, which found good agreement with atmospheric observations. We have performed simulations of the atmospheric aerosol distribution with and without the assimilation of MODIS aerosol optical depth (AOD. They indicate that the emissions of particulate matter need to be boosted with a factor of 2–4 to reproduce the global distribution of organic matter and black carbon. This discrepancy is also evident in the comparison of previously published top-down and bottom-up estimates. For the time being, a global enhancement of the particulate matter emissions by 3.4 is recommended. Validation with independent AOD and PM10

  1. Potential and limitations of multidecadal satellite soil moisture observations for selected climate model evaluation studies

    Directory of Open Access Journals (Sweden)

    A. Loew

    2013-09-01

    Full Text Available Soil moisture is an essential climate variable (ECV of major importance for land–atmosphere interactions and global hydrology. An appropriate representation of soil moisture dynamics in global climate models is therefore important. Recently, a first multidecadal, observation-based soil moisture dataset has become available that provides information on soil moisture dynamics from satellite observations (ECVSM, essential climate variable soil moisture. The present study investigates the potential and limitations of this new dataset for several applications in climate model evaluation. We compare soil moisture data from satellite observations, reanalysis and simulations from a state-of-the-art land surface model and analyze relationships between soil moisture and precipitation anomalies in the different dataset. Other potential applications like model parameter optimization or model initialization are not investigated in the present study. In a detailed regional study, we show that ECVSM is capable to capture well the interannual and intraannual soil moisture and precipitation dynamics in the Sahelian region. Current deficits of the new dataset are critically discussed and summarized at the end of the paper to provide guidance for an appropriate usage of the ECVSM dataset for climate studies.

  2. Robust H {sub {infinity}} output dynamic observer-based control of uncertain time-delay systems

    Energy Technology Data Exchange (ETDEWEB)

    Chen, J.-D. [Department of Electronic Engineering, National Kinmen Institute of Technology, Jinning, Kinmen 892, Taiwan (China)]. E-mail: tdchen@mail.kmit.edu.tw

    2007-01-15

    In this paper, the robustness and H {sub {infinity}} control problems of output dynamic observer-based control for a class of uncertain linear systems with time delay are considered. Under no disturbance input, the asymptotic stabilization for uncertain time-delay systems will be guaranteed. Linear matrix inequality (LMI) optimization approach is used to design three classes of the H {sub {infinity}} output dynamic controls. Based on the results of this paper, the constraint of matrix equality is not necessary for designing the observer-based controls.

  3. Low quality evidence of epidemiological observational studies on leishmaniasis in Brazil.

    Directory of Open Access Journals (Sweden)

    Bruno Trentini

    Full Text Available BACKGROUND: Brazil has implemented systematic control methods for leishmaniasis for the past 30 years, despite an increase in cases and continued spread of the disease to new regions. A lack high quality evidence from epidemiological observational studies impedes the development of novel control methods to prevent disease transmission among the population. Here, we have evaluated the quality of observational studies on leishmaniasis conducted in Brazil to highlight this issue. METHODS/PRINCIPAL FINDINGS: For this systematic review, all publications on leishmaniasis conducted in Brazil from January 1st, 2002 to December 31st, 2012 were screened via Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA checklist to select observational studies involving human subjects. The 283 included studies, representing only 14.1% of articles screened, were then further evaluated for quality of epidemiological methods and study design based on the STROBE (Strengthening the Reporting of Observational studies in Epidemiology checklists. Over half of these studies were descriptive or case reports (53.4%, 151, followed by cross-sectional (20.8%, n = 59, case-control (8.5%, n = 24, and cohort (6.0%, n = 17. Study design was not stated in 46.6% (n = 181 and incorrectly stated in 17.5% (n = 24. Comparison groups were utilized in just 39.6% (n = 112 of the publications, and only 13.4% (n = 38 employed healthy controls. Majority of studies were performed at the city-level (62.9%, n = 178, in contrast with two (0.7% studies performed at the national-level. Coauthorship networks showed the number of author collaborations rapidly decreased after three collaborations, with 70.9% (n = 659/929 of coauthors publishing only one article during the study period. CONCLUSIONS/SIGNIFICANCE: A review of epidemiological research in Brazil revealed a major lack of quality and evidence. While certain indicators suggested research methods may have improved in the

  4. Observer-Based Nonlinear Control of A Torque Motor with Perturbation Estimation

    Institute of Scientific and Technical Information of China (English)

    J Chen; E Prempain; Q H Wu

    2006-01-01

    This paper presents an observer-based nonlinear control method that was developed and implemented to provide accurate tracking control of a limited angle torque motor following a 50Hz reference waveform. The method is based on a robust nonlinear observer, which is used to estimate system states and perturbations and then employ input-output feedback linearization to compensate for the system nonlinearities and uncertainties. The estimation of system states and perturbations allows input-output linearization of the nonlinear system without an accurate mathematical model of nominal plant. The simulation results show that the observer-based nonlinear control method is superior in comparison with the conventional model-based state feedback linearizing controller.

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

    Science.gov (United States)

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

    2017-04-01

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

  6. Observing the Testing Effect using Coursera Video-recorded Lectures: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Paul Zhihao eYONG

    2016-01-01

    Full Text Available We investigated the testing effect in Coursera video-based learning. One hundred and twenty-three participants either (a studied an instructional video-recorded lecture four times, (b studied the lecture three times and took one recall test, or (c studied the lecture once and took three tests. They then took a final recall test, either immediately or a week later, through which their learning was assessed. Whereas repeated studying produced better recall performance than did repeated testing when the final test was administered immediately, testing produced better performance when the final test was delayed until a week after. The testing effect was observed using Coursera lectures. Future directions are documented.

  7. An Inverse Source Problem for a One-dimensional Wave Equation: An Observer-Based Approach

    KAUST Repository

    Asiri, Sharefa M.

    2013-05-25

    Observers are well known in the theory of dynamical systems. They are used to estimate the states of a system from some measurements. However, recently observers have also been developed to estimate some unknowns for systems governed by Partial differential equations. Our aim is to design an observer to solve inverse source problem for a one dimensional wave equation. Firstly, the problem is discretized in both space and time and then an adaptive observer based on partial field measurements (i.e measurements taken form the solution of the wave equation) is applied to estimate both the states and the source. We see the effectiveness of this observer in both noise-free and noisy cases. In each case, numerical simulations are provided to illustrate the effectiveness of this approach. Finally, we compare the performance of the observer approach with Tikhonov regularization approach.

  8. Study of connectivity in student teams by observation of their learning processes

    Science.gov (United States)

    Pacheco, Patricio H.; Correa, Rafael D.

    2016-05-01

    A registration procedure based data tracking classroom activities students formed into teams, which are immersed in basic learning processes, particularly physical sciences is presented. For the analysis of the data various mathematical tools to deliver results in numerical indicators linking their learning, performance, quality of relational nexus to transformation their emotions. The range of variables under observation and further study, which is influenced by the evolution of the emotions of the different teams of students, it also covers the traditional approach to information delivery from outside (teaching in lecture) or from inside each team (abilities of pupils) to instructional materials that enhance learning inquiry and persuasion.

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

    Energy Technology Data Exchange (ETDEWEB)

    Koleśnik-Gray, Maria M.; Krstić, Vojislav, E-mail: vojislav.krstic@fau.de [Department of Physics, Chair for Applied Physics, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Staudtstr. 7, 91058 Erlangen (Germany); Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), and AMBER at CRANN, Trinity College Dublin, College Green, Dublin 2 (Ireland); School of Physics, Trinity College Dublin, College Green, Dublin 2 (Ireland); Sorger, Christian; Weber, Heiko B. [Department of Physics, Chair for Applied Physics, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Staudtstr. 7, 91058 Erlangen (Germany); Biswas, Subhajit; Holmes, Justin D. [Materials Chemistry and Analysis Group, Department of Chemistry, Tyndall Institute, University College Cork, Cork (Ireland); Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), and AMBER at CRANN, Trinity College Dublin, College Green, Dublin 2 (Ireland)

    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.

  10. Neural Network Based Retrieval of Atmospheric Temperature Profile Using AMSU-A Observations

    Directory of Open Access Journals (Sweden)

    R. K. Gangwar

    2014-01-01

    Full Text Available The present study describes artificial neural network (ANN based approach for the retrieval of atmospheric temperature profiles from AMSU-A microwave temperature sounder. The nonlinear relationship between the temperature profiles and satellite brightness temperatures dictates the use of ANN, which is inherently nonlinear in nature. Since latitudinal variation of temperature is dominant one in the Earth’s atmosphere, separate network configurations have been established for different latitudinal belts, namely, tropics, mid-latitudes, and polar regions. Moreover, as surface emissivity in the microwave region of electromagnetic spectrum significantly influences the radiance (or equivalently the brightness temperature at the satellite altitude, separate algorithms have been developed for land and ocean for training the networks. Temperature profiles from National Center for Environmental Prediction (NCEP analysis and brightness temperature observations of AMSU-A onboard NOAA-19 for the year 2010 have been used for training of the networks. Further, the algorithm has been tested on the independent dataset comprising several months of 2012 AMSU-A observations. Finally, an error analysis has been performed by comparing retrieved profiles with collocated temperature profiles from NCEP. Errors in the tropical region are found to be less than those in the mid-latitude and polar regions. Also, in each region the errors over ocean are less than the corresponding ones over land.

  11. A Unified Model for BDS Wide Area and Local Area Augmentation Positioning Based on Raw Observations

    Directory of Open Access Journals (Sweden)

    Rui Tu

    2017-03-01

    Full Text Available In this study, a unified model for BeiDou Navigation Satellite System (BDS wide area and local area augmentation positioning based on raw observations has been proposed. Applying this model, both the Real-Time Kinematic (RTK and Precise Point Positioning (PPP service can be realized by performing different corrections at the user end. This algorithm was assessed and validated with the BDS data collected at four regional stations from Day of Year (DOY 080 to 083 of 2016. When the users are located within the local reference network, the fast and high precision RTK service can be achieved using the regional observation corrections, revealing a convergence time of about several seconds and a precision of about 2–3 cm. For the users out of the regional reference network, the global broadcast State-Space Represented (SSR corrections can be utilized to realize the global PPP service which shows a convergence time of about 25 min for achieving an accuracy of 10 cm. With this unified model, it can not only integrate the Network RTK (NRTK and PPP into a seamless positioning service, but also recover the ionosphere Vertical Total Electronic Content (VTEC and Differential Code Bias (DCB values that are useful for the ionosphere monitoring and modeling.

  12. Self-Organization Phenomenon Observed in Piezoelectric Transformer-based Excimer Lamp

    Science.gov (United States)

    Itoh, Haruo; Suzuki, Susumu; Teranishi, Kenji; Shimomura, Naoyuki

    An excimer lamp constructed by a piezoelectric transformer (PT) has been developed and studied in our laboratory. The excimer lamp is based on the excitation of dielectric barrier discharge (DBD) generated by the PT surface that induces high-voltage due to the piezoelectric effect. Spectroscopic measurement in the vacuum ultraviolet (VUV) region is performed for the excimer lamp filling with a He-Xe mixture and Ar. Emission spectra having a peak at 172 and 126 nm are found, which are respectively radiated from the Xe2* and Ar2* excimers that returns to ground states. A self-organization phenomenon (SOP) is also recognized in the He and Ar DBD. Static and time-resolved observations of the self-organized patterns are performed by a single reflex and ICCD cameras, respectively. The formation of self-organized patterns in argon requires a small amount of the air as an additive. From the time-resolved observation, we found dark spots arrayed hexagonally in a weak emission on the PT surface whose arrangement well coincides with that of bright hexagonal filaments. The dark spots are considered as the traces of the accumulated charges on the dielectric electrode, which interrupt the hexagonally filamentary discharges.

  13. Observing Deformation at Mt. Raung East Java Based on PALSAR-2 Imagery by Using Interferometric SAR

    Science.gov (United States)

    Arbad, Arliandy P.; Ardy, Achmad; Ashari, Ridwan A.

    2016-11-01

    In August 2015, Indonesia Center of Volcanology and Geological Hazard Mitigation (CVGHM) recorded of tectonic activities at Mt. Raung with maximum amplitude 2-32 mm and continuing the tremor quakes until the beginning of the 2016 eruption period. Mt. Raung is located at East Java Province, one of most active stratovolcano in Indonesia, typically erupt with explosive eruptions and another deadly hazards such as pyroclastic flow, lahar and volcanic gases. Radar imagery consequently proposes of value device for mapping and assessing of volcano oppurtunities. By this study, we propose InSAR method to observe deformation in Mt. Raung. Interferometric SAR derives the phase difference based on two images of PALSAR-2 observations taken in January 2015 and January 2016. According to the processing of interferometric SAR, those images must be coregistered into a stack, and we selected 2015 imagery as master and the other imagery as slave. We estimate the interferogram result to know the line-of-sight then be flattened by removing the topographic phase an inflating volcano (or any other landform) produces a pattern of concentric fringes in a radar interferogram from which the ffects of viewing geometry and topography have been removed. Finally, we expect the result ofInSAR processing technique to investigate ground deformation of Mt. Raung. It would be a capable and cost-effective way of enhancing the techniques normally used in geodetic monitoring to assess the next eruptive events.

  14. Aircraft-based observations and high-resolution simulations of an Icelandic dust storm

    Directory of Open Access Journals (Sweden)

    A.-M. Blechschmidt

    2012-11-01

    Full Text Available The first aircraft-based observations of an Icelandic dust storm are presented. The measurements were carried out over the ocean near Iceland's south coast in February 2007. This dust event occurred in conjunction with an easterly barrier jet of more than 30 m s−1. The aircraft measurements show high particle mass mixing ratios in an area of low wind speeds in the wake of Iceland near the coast, decreasing abruptly towards the jet. Simulations from the Weather Research and Forecasting Model coupled with Chemistry (WRF/Chem indicate that the measured high mass mixing ratios and observed low visibility inside the wake are due to dust transported from Icelandic sand fields towards the ocean. This is confirmed by meteorological station data. Glacial outwash terrains located near the Mýrdalsjökull glacier are among simulated dust sources. Sea salt aerosols produced by the impact of strong winds on the ocean surface started to dominate as the aircraft flew away from Iceland into the jet. The present results support recent studies which suggest that Icelandic deserts should be considered as important dust sources in global and regional climate models.

  15. UK pneumonectomy outcome study (UKPOS: a prospective observational study of pneumonectomy outcome

    Directory of Open Access Journals (Sweden)

    Davies Paul

    2009-07-01

    Full Text Available Abstract Background In order to assess the short term risks of pneumonectomy for lung cancer in contemporary practice a one year prospective observational study of pneumonectomy outcome was made. Current UK practice for pneumonectomy was observed to note patient and treatment factors associated with major complications. Methods A multicentre, prospective, observational cohort study was performed. All 35 UK thoracic surgical centres were invited to submit data to the study. All adult patients undergoing pneumonectomy for lung cancer between 1 January and 31 December 2005 were included. Patients undergoing pleuropneumonectomy, extended pneumonectomy, completion pneumonectomy following previous lobectomy and pneumonectomy for benign disease, were excluded from the study. The main outcome measure was suffering a major complication. Major complications were defined as: death within 30 days of surgery; treated cardiac arrhythmia or hypotension; unplanned intensive care admission; further surgery or inotrope usage. Results 312 pneumonectomies from 28 participating centres were entered. The major complication incidence was: 30-day mortality 5.4%; treated cardiac arrhythmia 19.9%; unplanned intensive care unit admission 9.3%; further surgery 4.8%; inotrope usage 3.5%. Age, American Society of Anesthesiologists physical status ≥ P3, pre-operative diffusing capacity for carbon monoxide (DLCO and epidural analgesia were collectively the strongest risk factors for major complications. Major complications prolonged median hospital stay by 2 days. Conclusion The 30 day mortality rate was less than 8%, in agreement with the British Thoracic Society guidelines. Pneumonectomy was associated with a high rate of major complications. Age, ASA physical status, DLCO and epidural analgesia appeared collectively most associated with major complications.

  16. Observing participating observation

    DEFF Research Database (Denmark)

    Keiding, Tina Bering

    2011-01-01

    Current methodology concerning participating observation in general leaves the act of observation unobserved. Approaching participating observation from systems theory offers fundamental new insights into the topic. Observation is always participation. There is no way to escape becoming...... as the idea of the naïve observer becomes a void. Not recognizing and observing oneself as observer and co-producer of empirical data simply leaves the process of observation as the major unobserved absorber of contingency in data production based on participating observation....

  17. Observing participating observation

    DEFF Research Database (Denmark)

    Keiding, Tina Bering

    2010-01-01

    Current methodology concerning participating observation in general leaves the act of observation unobserved. Approaching participating observation from systems theory offers fundamental new insights into the topic. Observation is always participation. There is no way to escape becoming...... as the idea of the naïve observer becomes a void. Not recognizing and observing oneself as observer and co-producer of empirical data simply leaves the process of observation as the major unobserved absorber of contingency in data production based on participating observation....

  18. Comparison of OMI UV observations with ground-based measurements at high northern latitudes

    Directory of Open Access Journals (Sweden)

    G. Bernhard

    2015-03-01

    Full Text Available The Dutch-Finnish Ozone Monitoring Instrument (OMI on board NASA's Aura spacecraft provides estimates of erythemal (sunburning ultraviolet (UV dose rates and erythemal daily doses. These data were compared with ground-based measurements at 13 stations located throughout the Arctic and Scandinavia from 60 to 83° N. The study corroborates results from earlier work, but is based on a longer time series (eight vs. two years and considers additional data products, such as the erythemal dose rate at the time of the satellite overpass. Furthermore, systematic errors in satellite UV data resulting from inaccuracies in the surface albedo climatology used in the OMI UV algorithm are systematically assessed. At times when the surface albedo is correctly known, OMI data typically exceed ground-based measurements by 0–11%. When the OMI albedo climatology exceeds the actual albedo, OMI data may be biased high by as much as 55%. In turn, when the OMI albedo climatology is too low, OMI data can be biased low by up to 59%. Such large negative biases may occur when reflections from snow and ice, which increase downwelling UV irradiance, are misinterpreted as reflections from clouds, which decrease the UV flux at the surface. Results suggest that a better OMI albedo climatology would greatly improve the accuracy of OMI UV data products even if year-to-year differences of the actual albedo cannot be accounted for. A pathway for improving the OMI albedo climatology is discussed. Results also demonstrate that ground-based measurements from the center of Greenland, where high, homogenous surface albedo is observed year round, are ideally suited to detect systematic problems or temporal drifts in estimates of surface UV irradiance from space.

  19. Copying competitors? Interdependency modulates stimulus-based retrieval of observed responses.

    Science.gov (United States)

    Giesen, Carina; Herrmann, Johanna; Rothermund, Klaus

    2014-10-01

    We investigated whether stimuli are integrated with responses that are merely observed, but not executed by oneself, and examined the moderating role of mutual dependency between coactors on the binding and retrieval of stimuli and observed responses. A prime-probe paradigm was shared between 2 coactors who took the roles of actor and observer in turns. We also varied the interdependency between the pairs of participants (cooperation vs. competition vs. independence). Results of Experiment 1 indicated that prime observers showed stimulus-based retrieval of observed responses when it was their turn to act in the 2 interdependent conditions, whereas prime observers in the independent condition did not. Results of Experiment 2 excluded the possibility that the stronger retrieval effects in the interdependent conditions are due to social facilitation of retrieval processes in general, as interdependency did not modulate stimulus-based retrieval of self-generated responses. We conclude that binding and retrieval of stimuli and observed responses is a conditionally automatic process that is contingent on mutual dependency between actor and observer.

  20. Relationship between Cloud Characteristics and Radar Reflectivity Based on Aircraft and Cloud Radar Co-observations

    Institute of Scientific and Technical Information of China (English)

    ZONG Rong; LIU Liping; YIN Yan

    2013-01-01

    Cloud properties were investigated based on aircraft and cloud radar co-observation conducted at Yitong,Jilin,Northeast China.The aircraft provided in situ measurements of cloud droplet size distribution,while the millimeter-wavelength cloud radar vertically scanned the same cloud that the aircraft penetrated.The reflectivity factor calculated from aircraft measurements was compared in detail with simultaneous radar observations.The results showed that the two reflectivities were comparable in warm clouds,but in ice cloud there were more differences,which were probably associated with the occurrence of liquid water.The acceptable agreement between reflectivities obtained in water cloud confirmed that it is feasible to derive cloud properties by using aircraft data,and hence for cloud radar to remotely sense cloud properties.Based on the dataset collected in warm clouds,the threshold of reflectivity to diagnose drizzle and cloud particles was studied by analyses of the probability distribution function of reflectivity from cloud particles and drizzle drops.The relationship between reflectivity factor (Z) and cloud liquid water content (LWC) was also derived from data on both cloud particles and drizzle.In comparison with cloud droplets,the relationship for drizzle was blurred by many scatter points and thus was less evident.However,these scatters could be partly removed by filtering out the drop size distribution with a large ratio of reflectivity and large extinction coefficient but small effective radius.Empirical relationships of Z-LWC for both cloud particles and drizzle could then be derived.

  1. A model observer based on human perception to quantify the detectability

    Science.gov (United States)

    Acharian, Georges; Guyader, Nathalie; Vignolle, Jean-Michel; Jutten, Christian

    2014-03-01

    In medical imaging, model observers such as the "Hotelling observer" and the "Non Prewhitening Matched Filter" have been proposed to detect objects in X-ray images. These models, based on decision theory, are applied over the entire image. In this paper, we developed a model that mimics some processes of human visual perception. The proposed model is locally applied on some particular areas that correspond to the salient areas of the object. By doing this, the model mimics the sequence of eye fixations that we make when we explore an image for example in order to detect an object. The study is divided into three parts: a psychophysical experiment to obtain human's performance to detect various objects in noises, a theoretical part to develop the proposed model, and finally, a result part. During the experiment, several participants were asked to detect objects in noisy images using a free search task. The luminance contrast of objects was adaptively adjusted according to their responses to obtain a percentage of correct detection for each object of 50 %. The proposed model, based on decision theory, was applied locally on some areas of the image that has a size corresponding to the high visual acuity of foveal vision. Areas were chosen according to their high saliency values computed through a bio-inspired model of visual attention. For each area, our model returned a detectability index. By supposing statistical independence between areas, the local indexes are combined into a global detectability index. Results show that the proposed model fits the results of the psychophysical experiment and outperforms classical models of the literature.

  2. The reporting of statistics in medical educational studies: an observational study

    Directory of Open Access Journals (Sweden)

    Desbiens Norman A

    2007-07-01

    Full Text Available Abstract Background There is confusion in the medical literature as to whether statistics should be reported in survey studies that query an entire population, as is often done in educational studies. Our objective was to determine how often statistical tests have been reported in such articles in two prominent journals that publish these types of studies. Methods For this observational study, we used electronic searching to identify all survey studies published in Academic Medicine and the Journal of General Internal Medicine in which an entire population was studied. We tallied whether inferential statistics were used and whether p-values were reported. Results Eighty-four articles were found: 62 in Academic Medicine and 22 in the Journal of General Internal Medicine. Overall, 38 (45% of the articles reported or stated that they calculated statistics: 35% in Academic Medicine and 73% in the Journal of General Internal Medicine. Conclusion Educational enumeration surveys frequently report statistical tests. Until a better case can be made for doing so, a simple rule can be proffered to researchers. When studying an entire population (e.g., all program directors, all deans, and all medical schools for factual information, do not perform statistical tests. Reporting percentages is sufficient and proper.

  3. Interannaul variations of the vertical and their possible influence on the star catalogs derived from ground-based astrometric observations

    Science.gov (United States)

    Li, Z. X.

    The efforts at Shanghai Observatory since 1991, in response to the Resolution of IAU Comm.19: "Applications of optical astrometry time and latitude programs", is described in the paper, especially the studies concerned with the interannual variations of the vertical and their influence on the astronomical studies. It is clear now that there is a component of the order 0.01 - 0.02" on an interannual time scale in latitude residuals which is correlated with geophysical phenomena on the Earth. A recent study has confirmed that the component discovered is actually the variation of the vertical, related to ground-based observation in astronomy. So, it should be emphasized now that the variation of the vertical is significant enough to be considered in astronomy from now on. Its influence on the past studies, including the star catalogs already published and the ERP before 1980 when optical astrometry observations were still used, should be studied in the future. In comparing the HIPPARCOS catalog with those derived by the past observations, we should keep in mind the existence of this error in an astrometric observation and its influence on the star catalogs and other results derived from ground-based astrometric observations.

  4. The data platform of national special environment and disaster field observation stations based on grid environment

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The Data Platform of Resource and Environment-whose data mainly come from field observation stations,spatial observations,and internet service institutions-is the base of data analysis and model simulation in geoscience research in China.Among this integrated data platform,the tasks of the data platform of field observation stations are principally data collection,management,assimilation,and share service.Taking into consideration the distributing characteristics of the data sources and the service objects,the authors formulated the framework of the field observation stations’ data platform based on the grid technology and designed its operating processes.The authors have further defined and analyzed the key functions and implementing techniques for each module.In a Linux operating system,validation tests for the data platform’s function on data replication,data synchronization,and unified data service have been conducted under an environment that of the simulating field stations.

  5. A behavior- and observation-based monitoring process for safety management.

    Science.gov (United States)

    Nascimento, Cesar F; Frutuoso E Melo, Paulo Fernando F

    2010-01-01

    The objective of this paper is to demonstrate that a combination of a behavior-based monitoring process--using an at-risk behavior and unsafe condition observation system--and an observation-based safety adherence monitoring process that can indicate the compliance level with well-defined and agreed safety critical aspects and operational practices and procedures will be an effective safety management tool. This tool herein described represents a particular case, developed by a Praxair Inc. subsidiary in Brazil. Other safety surveillance systems usually adopted in industrial environments can rarely be used on construction sites. They also do not share information, knowledge and skills among the safety staff and other professionals invited to observe, usually covering specific tasks or specific professionals only, not a complete working area, which causes functional observing and monitoring limitations in terms of capturing behaviors and environmental safety issues. This tool also offers a wide range of learning opportunities and continuous improvement.

  6. Ground-based multisite observations of two transits of HD 80606b

    CERN Document Server

    Shporer, A; Dreizler, S; Colon, K D; Wood-Vasey, W M; Choi, P I; Morley, C; Moutou, C; Welsh, W F; Pollaco, D; Starkey, D; Adams, E; Barros, S C C; Bouchy, F; Cabrera-Lavers, A; Cerutti, S; Coban, L; Costello, K; Deeg, H; Diaz, R F; Esquerdo, G A; Fernandez, J; Fleming, S W; Ford, E B; Fulton, B J; Good, M; Hebrard, G; Holman, M J; Hunt, M; Kadakia, S; Lander, G; Lockhart, M; Mazeh, T; Morehead, R C; Nelson, B E; Nortmann, L; Reyes, F; Roebuck, E; Rudy, A R; Ruth, R; Simpson, E; Vincent, C; Weaver, G; Xie, J -W

    2010-01-01

    We present ground-based optical observations of the September 2009 and January 2010 transits of HD 80606b. Based on 3 partial light curves of the September 2009 event, we derive a midtransit time of T_c [HJD] = 2455099.196 +- 0.026, which is about 1 sigma away from the previously predicted time. We observed the January 2010 event from 9 different locations, with most phases of the transit being observed by at least 3 different teams. We determine a midtransit time of T_c [HJD] = 2455210.6502 +- 0.0064, which is within 1.3 sigma of the time derived from a Spitzer observation of the same event.

  7. Observability-Based Approach to Design, Analysis and Optimization of Dynamical Systems

    Science.gov (United States)

    Alaeddini, Atiye

    The present dissertation aims to use the coupling between actuation and sensing in nonlinear systems to alternatively design a set of feasible control policies, to find the minimum number of sensors, or to find an optimal sensors configuration. Feasibility, here, means a combination of sensory system and control policy which guarantees observability. In some cases the optimality of the obtained solution is also considered. In some nonlinear systems, full observability requires active sensing, and will be shown how control policies that guarantee observability can be obtained by considering the geometry of the system dynamics. The observability matrix is used to test observability, whereas for the optimization problem observability Gramian matrix is used. This dissertation also considers the stability in designing controllers. The problem of designing a stabilizing control policy for a control-affine nonlinear system is addressed. The effect of time-varying control on the observability is investigated and shown to potentially improve the system observability. A particular application of the techniques considered here is the problem of designing network sensing and topology based on the observability criteria. The goal is to develop a protocol for the network which guarantees privacy. Furthermore, given a network of connected agents, we would like to determine which nodes should be observed to maximize information about the entire network. This dissertation begins with theoretical basis then moves towards applications of the theory. The first application is navigation of an autonomous ground robot with limited inertial sensing, motivated by the visuomotor system of insects. The second application is the problem of detecting an epidemic disease, which demonstrates design of an observability-based optimal network.

  8. Optimizing Prescription of Chinese Herbal Medicine for Unstable Angina Based on Partially Observable Markov Decision Process

    Directory of Open Access Journals (Sweden)

    Yan Feng

    2013-01-01

    Full Text Available Objective. Initial optimized prescription of Chinese herb medicine for unstable angina (UA. Methods. Based on partially observable Markov decision process model (POMDP, we choose hospitalized patients of 3 syndrome elements, such as qi deficiency, blood stasis, and turbid phlegm for the data mining, analysis, and objective evaluation of the diagnosis and treatment of UA at a deep level in order to optimize the prescription of Chinese herb medicine for UA. Results. The recommended treatment options of UA for qi deficiency, blood stasis, and phlegm syndrome patients were as follows: Milkvetch Root + Tangshen + Indian Bread + Largehead Atractylodes Rhizome (ADR=0.96630; Danshen Root + Chinese Angelica + Safflower + Red Peony Root + Szechwan Lovage Rhizome Orange Fruit (ADR=0.76; Snakegourd Fruit + Longstamen Onion Bulb + Pinellia Tuber + Dried Tangerine peel + Largehead Atractylodes Rhizome + Platycodon Root (ADR=0.658568. Conclusion. This study initially optimized prescriptions for UA based on POMDP, which can be used as a reference for further development of UA prescription in Chinese herb medicine.

  9. Optimizing prescription of chinese herbal medicine for unstable angina based on partially observable markov decision process.

    Science.gov (United States)

    Feng, Yan; Qiu, Yu; Zhou, Xuezhong; Wang, Yixin; Xu, Hao; Liu, Baoyan

    2013-01-01

    Objective. Initial optimized prescription of Chinese herb medicine for unstable angina (UA). Methods. Based on partially observable Markov decision process model (POMDP), we choose hospitalized patients of 3 syndrome elements, such as qi deficiency, blood stasis, and turbid phlegm for the data mining, analysis, and objective evaluation of the diagnosis and treatment of UA at a deep level in order to optimize the prescription of Chinese herb medicine for UA. Results. The recommended treatment options of UA for qi deficiency, blood stasis, and phlegm syndrome patients were as follows: Milkvetch Root + Tangshen + Indian Bread + Largehead Atractylodes Rhizome (ADR = 0.96630); Danshen Root + Chinese Angelica + Safflower + Red Peony Root + Szechwan Lovage Rhizome Orange Fruit (ADR = 0.76); Snakegourd Fruit + Longstamen Onion Bulb + Pinellia Tuber + Dried Tangerine peel + Largehead Atractylodes Rhizome + Platycodon Root (ADR = 0.658568). Conclusion. This study initially optimized prescriptions for UA based on POMDP, which can be used as a reference for further development of UA prescription in Chinese herb medicine.

  10. Ground-based observation of emission lines from the corona of a red-dwarf star.

    Science.gov (United States)

    Schmitt, J H; Wichmann, R

    2001-08-02

    All 'solar-like' stars are surrounded by coronae, which contain magnetically confined plasma at temperatures above 106 K. (Until now, only the Sun's corona could be observed in the optical-as a shimmering envelope during a total solar eclipse.) As the underlying stellar 'surfaces'-the photospheres-are much cooler, some non-radiative process must be responsible for heating the coronae. The heating mechanism is generally thought to be magnetic in origin, but is not yet understood even for the case of the Sun. Ultraviolet emission lines first led to the discovery of the enormous temperature of the Sun's corona, but thermal emission from the coronae of other stars has hitherto been detectable only from space, at X-ray wavelengths. Here we report the detection of emission from highly ionized iron (Fe XIII at 3,388.1 A) in the corona of the red-dwarf star CN Leonis, using a ground-based telescope. The X-ray flux inferred from our data is consistent with previously measured X-ray fluxes, and the non-thermal line width of 18.4 km s-1 indicates great similarities between solar and stellar coronal heating mechanisms. The accessibility and spectral resolution (45,000) of the ground-based instrument are much better than those of X-ray satellites, so a new window to the study of stellar coronae has been opened.

  11. System identification aided design of observer-based fault detection systems; Prozessidentifikations-basierter Entwurf beobachtergestuetzter Fehlerdetektionssysteme

    Energy Technology Data Exchange (ETDEWEB)

    Ding, S.X. [Fachgebiet Automatisierungstechnik und komplexe Systeme, Univ. Duisburg-Essen, Duisburg (Germany); Zhang Ping; Heyden, D. [Fakultaet Ingenieurwissenschaften an der Univ. Duisburg-Essen (Germany); Huang Biao [Dept. of Chemical and Materials Engineering, Univ. of Alberta (Canada); Ding, E.L. [Fachbereich Technische Physik, Fachhochschule Gelsenkirchen, Gelsenkirchen (Germany)

    2004-07-01

    This paper deals with problems of observer-based fault detection. An approach is presented, which enables the design of observer-based residual generators based on the process measurement or test data. The basic idea behind this approach is integrating the identification of the so-called fault detection model into the design of observer-based residual generators. (orig.)

  12. Full-Order Disturbance-Observer-Based Control for Singular Hybrid System

    Directory of Open Access Journals (Sweden)

    Xiuming Yao

    2013-01-01

    Full Text Available The problem of the disturbance-observer-based control for singular hybrid system with two types of disturbances is addressed in this paper. Under the assumption that the system states are, unavailable, full-order observers (for both system states and the disturbance and a nonlinear control scheme are constructed, such that the composite system can be guaranteed to be stochastically admissible, and the two types of disturbances can be attenuated and rejected, simultaneously. Based on the Lyapunov stability theory, sufficient conditions for the existence of the desired full-order disturbance-observer-based controllers are established in terms of linear matrix inequalities (LMIs. Finally, a numerical example is provided to show the effectiveness of the proposed approaches.

  13. Multi-viewpoint Smartphone AR-based Learning System for Solar Movement Observations

    Directory of Open Access Journals (Sweden)

    Ke Tian

    2014-06-01

    Full Text Available Understanding solar movement (e.g., solar diurnal motion is difficult for those are beginning to learn about astronomy. Previous research has revealed that observation-based learning can help make astronomical phenomena clearer to understand for such learners. In this research, Smartphone Augmented Reality (AR technology and 3D content were used to develop a multi-viewpoint Smartphone AR-based learning system (M-VSARLS for solar movement observations that can be used in the real-world environment. The goal of this research is to assess the usefulness of the system, usability of the AR function and 3D content, and the overall effect of the system on the learner’s motivation through task-based experiments with follow-up questionnaires. The results show that the M-VSARL system is effective in improving the observational skills and learning ability of learners, and in enhancing their motivation to learn about solar movement.

  14. On Distributed Reduced-Order Observer-Based Protocol for Linear Multiagent Consensus under Switching Topology

    Directory of Open Access Journals (Sweden)

    Yan Zhang

    2013-01-01

    Full Text Available We discuss linear multiagent systems consensus problem with distributed reduced-order observer-based protocol under switching topology. We use Jordan decomposition method to prove that the proposed protocols can solve consensus problem under directed fixed topology. By constructing a parameter-dependent common Lyapunov function, we prove that the distributed reduced-order observer-based protocol can also solve the continuous-time multi-agent consensus problem under the undirected switching interconnection topology. Then, we investigate the leader-following consensus problem and propose a reduced-order observer-based protocol for each following agent. By using similar analysis method, we can prove that all following agents can track the leader under a class of directed interaction topologies. Finally, the given simulation example also shows the effectiveness of our obtained result.

  15. Studying Sensing-Based Systems

    DEFF Research Database (Denmark)

    Kjærgaard, Mikkel Baun

    2013-01-01

    Recent sensing-based systems involve a multitude of users, devices, and places. These types of systems challenge existing approaches for conducting valid system evaluations. Here, the author discusses such evaluation challenges and revisits existing system evaluation methodologies....

  16. REFLECTIVE PRACTICE THROUGH JOURNAL WRITING AND PEER OBSERVATION: A Case Study

    Directory of Open Access Journals (Sweden)

    B. Samrajya LAKSHMI

    2014-10-01

    Full Text Available Journal writing and Peer Observation in an educational context have become popular techniques, with several different types of applications. They have now been used quite widely in both language teaching and in teacher training. However, despite its reported advantages in both teaching and research, there are not many Peer Observation and Diary studies available based on the writing of experienced language teachers. The Teacher participants maintain Journal writing and Peer Observation as a means of reflective practice. They consider these practices as a mirror, which reflects the teacher’s own image as