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Sample records for study bases study

  1. Data base management study

    NASA Technical Reports Server (NTRS)

    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.

  2. Computer Based Social Studies Instruction: A Qualitative Case Study

    ERIC Educational Resources Information Center

    Ulusoy, Mustafa

    2005-01-01

    In this study, the quality of the computer and Internet based social studies course was investigated. A case study design was chosen to understand, a) how computers are used in the eighth grade classroom, b) what the students' and teachers' perceptions are about the advantages and problems of using computers. Qualitative data sources showed that…

  3. Code Validation Study for Base Flows

    NASA Technical Reports Server (NTRS)

    Ascoli, Edward P.; Heiba, Adel H.; Lagnado, Ronald R.; Ungewitter, Ronald J.; Williams, Morgan

    1993-01-01

    New and old rocket launch concepts recommend the clustering of motors for improved lift capability. The flowfield of the base region of the rocket is very complex and can contain high temperature plume gases. These hot gases can cause catastrophic problems if not adequately designed for. To assess the base region characteristics, advanced computational fluid dynamics (CFD) is being used. As a precursor to these calculations the CFD code requires validation on base flows. The primary objective of this code validation study was to establish a high level of confidence in predicting base flows with the USA CFD code. USA has been extensively validated for fundamental flows and other applications. However, base heating flows have a number of unique characteristics so it was necessary to extend the existing validation for this class of problems. In preparation for the planned NLS 1.5 Stage base heating analysis, six case sets were studied to extend the USA code validation data base. This presentation gives a cursive review of three of these cases. The cases presented include a 2D axi-symmetric study, a 3D real nozzle study, and a 3D multi-species study. The results of all the studies show good general agreement with data with no adjustments to the base numerical algorithms or physical models in the code. The study proved the capability of the USA code for modeling base flows within the accuracy of available data.

  4. Code validation study for base flows

    NASA Astrophysics Data System (ADS)

    Ascoli, Edward P.; Heiba, Adel H.; Lagnado, Ronald R.; Ungewitter, Ronald J.; Williams, Morgan

    1993-07-01

    New and old rocket launch concepts recommend the clustering of motors for improved lift capability. The flowfield of the base region of the rocket is very complex and can contain high temperature plume gases. These hot gases can cause catastrophic problems if not adequately designed for. To assess the base region characteristics, advanced computational fluid dynamics (CFD) is being used. As a precursor to these calculations the CFD code requires validation on base flows. The primary objective of this code validation study was to establish a high level of confidence in predicting base flows with the USA CFD code. USA has been extensively validated for fundamental flows and other applications. However, base heating flows have a number of unique characteristics so it was necessary to extend the existing validation for this class of problems. In preparation for the planned NLS 1.5 Stage base heating analysis, six case sets were studied to extend the USA code validation data base. This presentation gives a cursive review of three of these cases. The cases presented include a 2D axi-symmetric study, a 3D real nozzle study, and a 3D multi-species study. The results of all the studies show good general agreement with data with no adjustments to the base numerical algorithms or physical models in the code. The study proved the capability of the USA code for modeling base flows within the accuracy of available data.

  5. Brain-Science Based Cohort Studies

    ERIC Educational Resources Information Center

    Koizumi, Hideaki

    2011-01-01

    This article describes a number of human cohort studies based on the concept of brain-science and education. These studies assess the potential effects of new technologies on babies, children and adolescents, and test hypotheses drawn from animal and genetic case studies to see if they apply to people. A flood of information, virtual media,…

  6. Brain-Science Based Cohort Studies

    ERIC Educational Resources Information Center

    Koizumi, Hideaki

    2011-01-01

    This article describes a number of human cohort studies based on the concept of brain-science and education. These studies assess the potential effects of new technologies on babies, children and adolescents, and test hypotheses drawn from animal and genetic case studies to see if they apply to people. A flood of information, virtual media,…

  7. Defense Industrial Base Capabilities Study: Force Application

    DTIC Science & Technology

    2004-10-01

    Base : A Roadmap. This report identified the need for systematic evaluation of the ability of the defense industrial base to develop and provide...functional, operational effects-based warfighting capabilities. The Defense Industrial Base Capabilities Study (DIBCS) series is a systematic assessment of...critical technologies needed in the 21st century defense industrial base to meet warfighter capabilities, as framed by the Joint Staff’s functional

  8. Defense Industrial Base Capabilities Study: Protection

    DTIC Science & Technology

    2004-12-01

    2003, the Office of the Deputy Under Secretary of Defense for Industrial Policy, ODUSD (IP), produced Transforming the Defense Industrial Base : A...Roadmap. This report identified the need for systematic evaluation of the ability of the defense industrial base to develop and provide functional...operational effects-based warfighting capabilities. The Defense Industrial Base Capabilities Study (DIBCS) series is a systematic assessment of critical

  9. Systems engineering studies of lunar base construction

    NASA Astrophysics Data System (ADS)

    Morgenthaler, George W.

    1991-11-01

    Many ingenious concepts have been proposed for lunar base construction, but few systematic studies exist which relate time-consistent lunar base construction technologies and the choice of lunar base approach with the long-term SEI objectives - i.e., lunar indigenous base construction and Mars Exploration equipment development. To fill this gap, CSC has taken a two-pronged approach. First, the Center undertook basic geotechnical investigations of lunar soil, fabrication of a scale prototype of a lunar construction crane, a multi-robot construction team laboratory experiment, and a preliminary design of lunar base structures. Second, during Jun. and Jul. 1991 two lunar base construction systems engineering studies were accomplished - a 'near term lunar base' study, and a 'far-term lunar base' study. The goals of these studies were to define the major lunar base construction research problems in consistent technology/construction frameworks, and to define design requirements for construction equipment such as a lunar crane and a regolith mover. The 'near-term lunar base' study examined three different construction concepts for a lunar base comprised of pre-fabricated, pre-tested, Space Station Freedom-type modules, which would be covered with regolith shielding. Concept A used a lunar crane for unloading and transportation; concept B, a winch and cart; and concept C, a walker to move the modules from the landing site to the base site and assemble them. To evaluate the merits of each approach, calculations were made of mass efficiency measure, source mass, reliability, far-term base mass, Mars base mass, and base assembly time. The model thus established was also used to define the requirements for crane speed and regolith mover m(sup 3)/sec rates. A major problem addressed is how to 'mine' the regolith and stack it over the habitats as shielding. To identify when the cost of using indigenous lunar materials to construct the base exceeds the cost of development and

  10. Systems engineering studies of lunar base construction

    NASA Technical Reports Server (NTRS)

    Morgenthaler, George W.

    1991-01-01

    Many ingenious concepts have been proposed for lunar base construction, but few systematic studies exist which relate time-consistent lunar base construction technologies and the choice of lunar base approach with the long-term SEI objectives - i.e., lunar indigenous base construction and Mars Exploration equipment development. To fill this gap, CSC has taken a two-pronged approach. First, the Center undertook basic geotechnical investigations of lunar soil, fabrication of a scale prototype of a lunar construction crane, a multi-robot construction team laboratory experiment, and a preliminary design of lunar base structures. Second, during Jun. and Jul. 1991 two lunar base construction systems engineering studies were accomplished - a 'near term lunar base' study, and a 'far-term lunar base' study. The goals of these studies were to define the major lunar base construction research problems in consistent technology/construction frameworks, and to define design requirements for construction equipment such as a lunar crane and a regolith mover. The 'near-term lunar base' study examined three different construction concepts for a lunar base comprised of pre-fabricated, pre-tested, Space Station Freedom-type modules, which would be covered with regolith shielding. Concept A used a lunar crane for unloading and transportation; concept B, a winch and cart; and concept C, a walker to move the modules from the landing site to the base site and assemble them. To evaluate the merits of each approach, calculations were made of mass efficiency measure, source mass, reliability, far-term base mass, Mars base mass, and base assembly time. The model thus established was also used to define the requirements for crane speed and regolith mover m(sup 3)/sec rates. A major problem addressed is how to 'mine' the regolith and stack it over the habitats as shielding. To identify when the cost of using indigenous lunar materials to construct the base exceeds the cost of development and

  11. Interdisciplinary Study with Computer-Based Multimedia.

    ERIC Educational Resources Information Center

    Couch, John D.; And Others

    Interdisciplinary study with computer-based multimedia in the classroom is reviewed. The multimedia revolution involves multiple technologies and multiple modes of sensation, but the computer is at the heart of this revolution. Despite the many challenges, interest is strong for multimedia courseware. The predicted market is enormous, and nowhere…

  12. Competency Based Education: A Sociological Study.

    ERIC Educational Resources Information Center

    Graham, Thomas E.

    This study focuses on the Competency Based Education (CBE) movement in a small Ohio school district, asking whether it represents radical change or reenforces status-quo social stratification. CBE was a product of the recent public demand for more educational accountability. It is a radical shift from traditional U.S. education insofar as it…

  13. Interdisciplinary Study with Computer-Based Multimedia.

    ERIC Educational Resources Information Center

    Couch, John D.; And Others

    Interdisciplinary study with computer-based multimedia in the classroom is reviewed. The multimedia revolution involves multiple technologies and multiple modes of sensation, but the computer is at the heart of this revolution. Despite the many challenges, interest is strong for multimedia courseware. The predicted market is enormous, and nowhere…

  14. Competency Based Education: A Sociological Study.

    ERIC Educational Resources Information Center

    Graham, Thomas E.

    This study focuses on the Competency Based Education (CBE) movement in a small Ohio school district, asking whether it represents radical change or reenforces status-quo social stratification. CBE was a product of the recent public demand for more educational accountability. It is a radical shift from traditional U.S. education insofar as it…

  15. Using clinical data bases to study schizophrenia.

    PubMed

    Weiser, Mark; Davidson, Michael

    2008-11-01

    Studying psycho-pathology using clinical registries enables a birds-eye view of all mental illness, and allows researchers to look at each illness in the context of other mental illnesses. The papers presented in this issue indicate that at least some of the symptoms commonly present in schizophrenia are actually present in other mental disorders and may even be present in individuals without diagnosed psychiatric disorders. Although there are some disadvantages to research based on clinical registries, this method enables study designs not be possible with conventional research paradigms.

  16. Army Reserve Capabilities-Based Prioritization Study

    DTIC Science & Technology

    2008-08-15

    businesses derive any benefit from using the SWOT strategic planning tool, which is based on analysis of a company’s strengths, weaknesses, opportunities...Study TRADOC Analysis Center PO Box 8695 Monterey, CA 93943-0692 TRAC-M-TR-08-051 15 August 2008...Tollefson Mr. Andrew Cherry COL Jeffrey Schamburg TRADOC Analysis Center PO Box 8695 Monterey, CA 93943-0692 ii REPORT

  17. ASTM/NBS base stock consistency study

    SciTech Connect

    Frassa, K.A.

    1980-11-01

    This paper summarizes the scope of a cooperative ASTM/NBS program established in June 1979. The contemplated study will ascertain the batch-to-batch consistency of re-refined and virgin base stocks manufactured by various processes. For one year, approximately eight to ten different base stocks samples, will be obtained by NBS every two weeks. One set of bi-monthly samples will be forwarded to each participant, on a coded basis monthly. Seven to eight samples will be obtained from six different re-refining processes and two virgin oil samples from a similar manufacturing process. The participants will report their results on a monthly basis. The second set of samples will be retained by NBS for an interim monthly sample study, if required, based on data analysis. Each sample's properties will be evaluated using various physical tests, chemical tests, and bench tests. The total testing program should define the batch-to-batch base stock consistency short of engine testing.

  18. Study of cluster headache: A hospital-based study.

    PubMed

    Bhargava, Amita; Pujar, Guruprasad S; Banakar, Basavaraj F; Shubhakaran, K; Kasundra, Gaurav; Bhushan, Bharat

    2014-10-01

    Cluster headache (CH) is uncommon and most painful of all primary headaches, and continues to be managed suboptimally because of wrong diagnosis. It needs to be diagnosed correctly and specifically treated. There are few studies and none from this region on CH. To study the detailed clinical profile of CH patients and to compare them among both the genders. Study was conducted at Mahatma Gandhi hospital, Jodhpur (from January 2011to December 2013). Study comprises 30 CH patients diagnosed according to International Headache Society guidelines (ICHD-II). Routine investigations and MRI brain was done in all patients. All measurements were reported as mean ± SD. Categorical variables were compared using the Chi-square test, and continuous variables were compared using Student's t-test. SPSS for Windows, Version 16.0, was used for statistical analyses with the significance level set at P = 0.05. M: F ratio was 9:1. Age at presentation was from 22-60 years (mean - 38 years). Latency before diagnosis was 3 months-12 years (mean - 3.5 years). All suffered from episodic CH and aura was found in none. Pain was strictly unilateral (right-19, left-11), predominantly over temporal region-18 (60%). Pain intensity was severe in 27 (90%) and moderate in 3 (10%). Pain quality was throbbing in 12 (40%). Peak intensity was reached in 5 minutes-30 minutes and attack duration varied from 30 minutes to 3 hours (mean - 2.45 hours). Among autonomic features, conjunctival injection-23 (76.6%) and lacrimation-25 (83.3%) were most common. Restlessness during episode was found in 80%. CH duration varied from 10 days to 12 weeks. Circadian periodicity for attacks was noted in 24 (80%). Results are consistent with other studies on many accounts, but is different from Western studies with respect to low frequency of family history, chronic CH, restlessness and aura preceeding the attack. Detailed elicitation of history is paramount as misdiagnosis is common.

  19. Si-based Nanoparticles: a biocompatibility study

    NASA Astrophysics Data System (ADS)

    Rivolta, I.; Lettiero, B.; Panariti, A.; D'Amato, R.; Maurice, V.; Falconieri, M.; Herlein, N.; Borsella, E.; Miserocchi, G.

    2010-10-01

    Exposure to silicon nanoparticles (Si-NPs) may occur in professional working conditions or for people undergoing a diagnostic screening test. Despite the fact that silicon is known as a non-toxic material, in the first case the risk is mostly related to the inhalation of nanoparticles, thus the most likely route of entry is across the lung alveolar epithelium. In the case of diagnostic imaging, nanoparticles are usually injected intravenously and Si-NPs could impact on the endothelial wall. In our study we investigated the interaction between selected Si-based NPs and an epithelial lung cell line. Our data showed that, despite the overall silicon biocompatibility, however accurate studies of the potential toxicity induced by the nanostructure and engineered surface characteristics need to be accurately investigated before Si nanoparticles can be safely used for in vivo applications as bio-imaging, cell staining and drug delivery.

  20. Studies of anisotropy of iron based superconductors

    SciTech Connect

    Murphy, Jason A.

    2013-01-01

    To study the electronic anisotropy in iron based superconductors, the temperature dependent London penetration depth, Δλ(T), have been measured in several compounds, along with the angular dependent upper critical field, Hc2(T). Study was undertaken on single crystals of Ba(Fe1-xCox)2As2 with x=0.108 and x=0.127, in the overdoped range of the doping phase diagram, characterized by notable modulation of the superconducting gap. Heavy ion irradiation with matching field doses of 6 T and 6.5 T respectively, were used to create columnar defects and to study their effect on the temperature Δλ(T). The variation of the low-temperature penetration depth in both pristine and irradiated samples was fitted with a power-law function Δλ(T) = ATn. Irradiation increases the magnitude of the pre-factor A and decreases the exponent n, similar to the effect on the optimally doped samples. This finding supports the universal s ± scenario for the whole doping range.

  1. Design Study: Rocket Based MHD Generator

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This report addresses the technical feasibility and design of a rocket based MHD generator using a sub-scale LOx/RP rocket motor. The design study was constrained by assuming the generator must function within the performance and structural limits of an existing magnet and by assuming realistic limits on (1) the axial electric field, (2) the Hall parameter, (3) current density, and (4) heat flux (given the criteria of heat sink operation). The major results of the work are summarized as follows: (1) A Faraday type of generator with rectangular cross section is designed to operate with a combustor pressure of 300 psi. Based on a magnetic field strength of 1.5 Tesla, the electrical power output from this generator is estimated to be 54.2 KW with potassium seed (weight fraction 3.74%) and 92 KW with cesium seed (weight fraction 9.66%). The former corresponds to a enthalpy extraction ratio of 2.36% while that for the latter is 4.16%; (2) A conceptual design of the Faraday MHD channel is proposed, based on a maximum operating time of 10 to 15 seconds. This concept utilizes a phenolic back wall for inserting the electrodes and inter-electrode insulators. Copper electrode and aluminum oxide insulator are suggested for this channel; and (3) A testing configuration for the sub-scale rocket based MHD system is proposed. An estimate of performance of an ideal rocket based MHD accelerator is performed. With a current density constraint of 5 Amps/cm(exp 2) and a conductivity of 30 Siemens/m, the push power density can be 250, 431, and 750 MW/m(sup 3) when the induced voltage uB have values of 5, 10, and 15 KV/m, respectively.

  2. Knowledge data base system for twins study.

    PubMed

    Reina, S; Miozza, F

    1994-01-01

    The medical research on twins, carried out at the Gregor Mendel Institute for Medical Genetics and Twin Study in Rome over the past four decades, has resulted in a vast collection of clinical paper records. A challenge was presented by the need for a more secure method of storage to preserve this enormously valuable historical and scientific patrimony and to render its contents more easily accessible for research purposes. We met the challenge by planning and developing the computerization of this material. New concepts, currently being explored in biomedical informatics, were applied to build a Knowledge Data Base System, using a fourth-generation language (SQL). This architecturally innovative computer system enables its users to manipulate data supplied, rather than just simply storing it. Based on heuristic relational criteria between variables and parameters, the system is employed to solve problems of sibling design analysis typically arising from twins' records, but is also equipped to meet future data base requirements. Another feature of the system is its users' ability to pull off data in the form of regular automated reports, which are distributed through a Local Area Network (LAN). Through a Bulletin Board System (BBS) and modem, any scientist (outside as well as within the Institute) is thus able to access data and exchange scientific information.

  3. Population-based study on infant mortality.

    PubMed

    Lima, Jaqueline Costa; Mingarelli, Alexandre Marchezoni; Segri, Neuber José; Zavala, Arturo Alejandro Zavala; Takano, Olga Akiko

    2017-03-01

    Although Brazil has reduced social, economic and health indicators disparities in the last decade, intra- and inter-regional differences in child mortality rates (CMR) persist in regions such as the state capital of Mato Grosso. This population-based study aimed to investigate factors associated with child mortality in five cohorts of live births (LB) of mothers living in Cuiabá (MT), Brazil, 2006-2010, through probabilistic linkage in 47,018 LB. We used hierarchical logistic regression analysis. Of the 617 child deaths, 48% occurred in the early neonatal period. CMR ranged from 14.6 to 12.0 deaths per thousand LB. The following remained independently associated with death: mothers without companion (OR = 1.32); low number of prenatal consultations (OR = 1.65); low birthweight (OR = 4.83); prematurity (OR = 3.05); Apgar ≤ 7 at the first minute (OR = 3.19); Apgar ≤ 7 at the fifth minute (OR = 4.95); congenital malformations (OR = 14.91) and male gender (OR = 1.26). CMR has declined in Cuiabá, however, there is need to guide public healthcare policies in the prenatal and perinatal period to reduce early neonatal mortality and further studies to identify the causes of preventable deaths.

  4. Ground Based Studies of the Outer Planets

    NASA Technical Reports Server (NTRS)

    Trafton, Laurence M.

    2005-01-01

    This report covers progress to date under this grant on our continuing program to conduct ground based studies of the outer solar system planets and satellites, with emphasis on spectroscopy and atmospheric phenomena. The research continues under our new PAST grant, NNG04G131G beginning 5/1/2004. The original period of performance of the subject grant was 3/1/2001 to 2/28/2004, but was extended one year at no cost. Although there is some overlap in the scientific projects conducted during the extended year with those of the new grant, this report is confined to the portion of the work funded under NAG5-10435. The primary goals for this grant period were a comparative study of outer planet thermospheres/ionospheres near solar maximum, extended to the mid-IR, and the investigation of molecular dimers in outer solar system atmospheres. This project supports NASA's planned space missions, Jupiter Polar Orbiter, outer Planet Microprobes, and the recent Cassini flyby of Jupiter. It also supports the OSS strategic plan themes, The Exploration of the Solar System and The Sun-Earth Connection/ Understanding comparative planetary space environments.

  5. Laminar Diffusion Flame Studies (Ground- and Space-Based Studies)

    NASA Technical Reports Server (NTRS)

    Dai, Z.; El-Leathy, A. M.; Lin, K.-C.; Sunderland, P. B.; Xu, F.; Faeth, G. M.; Urban, D. L. (Technical Monitor); Yuan, Z.-G. (Technical Monitor)

    2000-01-01

    Laminar diffusion flames are of interest because they provide model flame systems that are far more tractable for analysis and experiments than more practical turbulent diffusion flames. Certainly, understanding flame processes within laminar diffusion flames must precede understanding these processes in more complex turbulent diffusion flames. In addition, many properties of laminar diffusion flames are directly relevant to turbulent diffusion flames using laminar flamelet concepts. Laminar jet diffusion flame shapes (luminous flame boundaries) have been of particular interest since the classical study of Burke and Schumann because they are a simple nonintrusive measurement that is convenient for evaluating flame structure predictions. Thus, consideration of laminar flame shapes is undertaken in the following, emphasizing conditions where effects of gravity are small, due to the importance of such conditions to practical applications. Another class of interesting properties of laminar diffusion flames are their laminar soot and smoke point properties (i.e., the flame length, fuel flow rate, characteristic residence time, etc., at the onset of soot appearance in the flame (the soot point) and the onset of soot emissions from the flame (the smoke point)). These are useful observable soot properties of nonpremixed flames because they provide a convenient means to rate several aspects of flame sooting properties: the relative propensity of various fuels to produce soot in flames; the relative effects of fuel structure, fuel dilution, flame temperature and ambient pressure on the soot appearance and emission properties of flames; the relative levels of continuum radiation from soot in flames; and effects of the intrusion of gravity (or buoyant motion) on emissions of soot from flames. An important motivation to define conditions for soot emissions is that observations of laminar jet diffusion flames in critical environments, e.g., space shuttle and space station

  6. Lunar base thermoelectric power station study

    NASA Technical Reports Server (NTRS)

    Determan, William; Frye, Patrick; Mondt, Jack; Fleurial, Jean-Pierre; Johnson, Ken; Stapfer, G.; Brooks, Michael D.; Heshmatpour, Ben

    2006-01-01

    Under NASA's Project Prometheus, the Nuclear Systems Program, the Jet Propulsion Laboratory, Pratt & Whitney Rocketdyne, and Teledyne Energy Systems have teamed with a number of universities, under the Segmented Thermoelectric Multicouple Converter (STMC) program, to develop the next generation of advanced thermoelectric converters for space reactor power systems. Work on the STMC converter assembly has progressed to the point where the lower temperature stage of the segmented multicouple converter assembly is ready for laboratory testing and the upper stage materials have been identified and their properties are being characterized. One aspect of the program involves mission application studies to help define the potential benefits from the use of these STMC technologies for designated NASA missions such as the lunar base power station where kilowatts of power are required to maintain a permanent manned presence on the surface of the moon. A modular 50 kWe thermoelectric power station concept was developed to address a specific set of requirements developed for this mission. Previous lunar lander concepts had proposed the use of lunar regolith as in-situ radiation shielding material for a reactor power station with a one kilometer exclusion zone radius to minimize astronaut radiation dose rate levels. In the present concept, we will examine the benefits and requirements for a hermetically-sealed reactor thermoelectric power station module suspended within a man-made lunar surface cavity. The concept appears to maximize the shielding capabilities of the lunar regolith while minimizing its handling requirements. Both thermal and nuclear radiation levels from operation of the station, at its 100-m exclusion zone radius, were evaluated and found to be acceptable. Site preparation activities are reviewed and well as transport issues for this concept. The goal of the study was to review the entire life cycle of the unit to assess its technical problems and technology

  7. Lunar Base Thermoelectric Power Station Study

    SciTech Connect

    Determan, William; Frye, Patrick; Mondt, Jack; Fleurial, Jean-Pierre; Johnson, Ken; Stapfer, Gerhard; Brooks, Michael; Heshmatpour, Ben

    2006-01-20

    Under NASA's Project Prometheus, the Nuclear Space Power Systems Program, the Jet Propulsion Laboratory, Pratt and Whitney Rocketdyne, and Teledyne Energy Systems have teamed with a number of universities, under the Segmented Thermoelectric Multicouple Converter (STMC) Task, to develop the next generation of advanced thermoelectric converters for space reactor power systems. Work on the STMC converter assembly has progressed to the point where the lower temperature stage of the segmented multicouple converter assembly is ready for laboratory testing, and promising candidates for the upper stage materials have been identified and their properties are being characterized. One aspect of the program involves mission application studies to help define the potential benefits from the use of these STMC technologies for designated NASA missions such as a lunar base power station where kilowatts of power would be required to maintain a permanent manned presence on the surface of the moon. A modular 50 kWe thermoelectric power station concept was developed to address a specific set of requirements developed for this particular mission concept. Previous lunar lander concepts had proposed the use of lunar regolith as in-situ radiation shielding material for a reactor power station with a one kilometer exclusion zone radius to minimize astronaut radiation dose rate levels. In the present concept, we will examine the benefits and requirements for a hermetically-sealed reactor thermoelectric power station module suspended within a man-made lunar surface cavity. The concept appears to maximize the shielding capabilities of the lunar regolith while minimizing its handling requirements. Both thermal and nuclear radiation levels from operation of the station, at its 100-m exclusion zone radius, were evaluated and found to be acceptable. Site preparation activities are reviewed as well as transport issues for this concept. The goal of the study was to review the entire life cycle of

  8. Lunar Base Thermoelectric Power Station Study

    NASA Astrophysics Data System (ADS)

    Determan, William; Frye, Patrick; Mondt, Jack; Fleurial, Jean-Pierre; Johnson, Ken; Stapfer, Gerhard; Brooks, Michael; Heshmatpour, Ben

    2006-01-01

    Under NASA's Project Prometheus, the Nuclear Space Power Systems Program, the Jet Propulsion Laboratory, Pratt & Whitney Rocketdyne, and Teledyne Energy Systems have teamed with a number of universities, under the Segmented Thermoelectric Multicouple Converter (STMC) Task, to develop the next generation of advanced thermoelectric converters for space reactor power systems. Work on the STMC converter assembly has progressed to the point where the lower temperature stage of the segmented multicouple converter assembly is ready for laboratory testing, and promising candidates for the upper stage materials have been identified and their properties are being characterized. One aspect of the program involves mission application studies to help define the potential benefits from the use of these STMC technologies for designated NASA missions such as a lunar base power station where kilowatts of power would be required to maintain a permanent manned presence on the surface of the moon. A modular 50 kWe thermoelectric power station concept was developed to address a specific set of requirements developed for this particular mission concept. Previous lunar lander concepts had proposed the use of lunar regolith as in-situ radiation shielding material for a reactor power station with a one kilometer exclusion zone radius to minimize astronaut radiation dose rate levels. In the present concept, we will examine the benefits and requirements for a hermetically-sealed reactor thermoelectric power station module suspended within a man-made lunar surface cavity. The concept appears to maximize the shielding capabilities of the lunar regolith while minimizing its handling requirements. Both thermal and nuclear radiation levels from operation of the station, at its 100-m exclusion zone radius, were evaluated and found to be acceptable. Site preparation activities are reviewed as well as transport issues for this concept. The goal of the study was to review the entire life cycle of the

  9. Lunar base thermoelectric power station study

    NASA Technical Reports Server (NTRS)

    Determan, William; Frye, Patrick; Mondt, Jack; Fleurial, Jean-Pierre; Johnson, Ken; Stapfer, G.; Brooks, Michael D.; Heshmatpour, Ben

    2006-01-01

    Under NASA's Project Prometheus, the Nuclear Systems Program, the Jet Propulsion Laboratory, Pratt & Whitney Rocketdyne, and Teledyne Energy Systems have teamed with a number of universities, under the Segmented Thermoelectric Multicouple Converter (STMC) program, to develop the next generation of advanced thermoelectric converters for space reactor power systems. Work on the STMC converter assembly has progressed to the point where the lower temperature stage of the segmented multicouple converter assembly is ready for laboratory testing and the upper stage materials have been identified and their properties are being characterized. One aspect of the program involves mission application studies to help define the potential benefits from the use of these STMC technologies for designated NASA missions such as the lunar base power station where kilowatts of power are required to maintain a permanent manned presence on the surface of the moon. A modular 50 kWe thermoelectric power station concept was developed to address a specific set of requirements developed for this mission. Previous lunar lander concepts had proposed the use of lunar regolith as in-situ radiation shielding material for a reactor power station with a one kilometer exclusion zone radius to minimize astronaut radiation dose rate levels. In the present concept, we will examine the benefits and requirements for a hermetically-sealed reactor thermoelectric power station module suspended within a man-made lunar surface cavity. The concept appears to maximize the shielding capabilities of the lunar regolith while minimizing its handling requirements. Both thermal and nuclear radiation levels from operation of the station, at its 100-m exclusion zone radius, were evaluated and found to be acceptable. Site preparation activities are reviewed and well as transport issues for this concept. The goal of the study was to review the entire life cycle of the unit to assess its technical problems and technology

  10. Severe neonatal hypernatraemia: a population based study.

    PubMed

    Oddie, Sam Joseph; Craven, Vanessa; Deakin, Kathryn; Westman, Janette; Scally, Andrew

    2013-09-01

    To describe incidence, presentation, treatment and short term outcomes of severe neonatal hypernatraemia (SNH, sodium ≥160 mmol/l). Prospective, population based surveillance study over 13 months using the British Paediatric Surveillance Unit. Cases were >33 weeks gestation at birth, fed breast or formula milk and <28 days of age at presentation. Of 62 cases of SNH reported (7, 95% CI 5.4 to 9.0 per 1 00 000 live births), 61 mothers had intended to achieve exclusive breast feeding. Infants presented at median day 6 (range 2-17) with median weight loss of 19.5% (range 8.9-30.9). 12 had jaundice and 57 weight loss as a presenting feature. 58 presented with weight loss ≥15%. 25 babies had not stooled in the 24 h prior to admission. Serum sodium fell by median 12.9 mmol/l per 24 h (range 0-30). No baby died, had seizures or coma or was treated with dialysis or a central line. At discharge, babies had regained 11% of initial birth weight after a median admission of 5 (range 2-14) days. 10 were exclusively breast fed on discharge from hospital. Neonatal hypernatraemia at this level, in this population, is strongly associated with weight loss. It occurs almost exclusively after attempts to initiate breast feeding, occurs uncommonly and does not appear to be associated with serious short term morbidities, beyond admission to hospital.

  11. Studies of anisotropy of iron based superconductors

    SciTech Connect

    Murphy, Jason

    2013-01-01

    To study the electronic anisotropy in iron based superconductors, the temperature dependent London penetration depth, Δλ (T), have been measured in several compounds, along with the angular dependent upper critical field, Hc2(T). Study was undertaken on single crystals of Ba(Fe1-xCox)2As2 with x=0.108 and x=0.127, in the overdoped range of the doping phase diagram, characterized by notable modulation of the superconducting gap. Heavy ion irradiation with matching field doses of 6 T and 6.5 T respectively, were used to create columnar defects and to study their effect on the temperature Δλ (T). The variation of the low-temperature penetration depth in both pristine and irradiated samples was fitted with a power-law function Δλ (T) = ATn. Irradiation increases the magnitude of the pre-factor A and decreases the exponent n, similar to the effect on the optimally doped samples. This finding supports the universal s± scenario for the whole doping range. Knowing that the s± gap symmetry exists across the superconducting dome for the electron doped systems, we next looked at λ (T), in optimally - doped, SrFe2(As1-xPx)2, x =0.35. Both, as-grown (Tc ~ 25 K) and annealed (Tc ~ 35 K) single crystals of SrFe2(As1-xPx)2 were measured. Annealing decreases the absolute value of the London penetration depth from λ(0) = 300 ± 10 nm in as-grown samples to λ (0) = 275±10 nm. At low temperatures, λ (T) ~ T indicates a superconducting gap with line nodes. Analysis of the full-temperature range superfluid density is consistent with the line nodes, but differs from the simple single-gap d-wave. The observed behavior is very similar to that of BaFe2(As1-xPx)2, showing that isovalently substituted pnictides are inherently different from

  12. Study of wheat protein based materials

    NASA Astrophysics Data System (ADS)

    Ye, Peng

    Wheat gluten is a naturally occurring protein polymer. It is produced in abundance by the agricultural industry, is biodegradable and very inexpensive (less than $0.50/lb). It has unique viscoelastic properties, which makes it a promising alternative to synthetic plastics. The unplasticized wheat gluten is, however, brittle. Plasticizers such as glycerol are commonly used to give flexibility to the articles made of wheat gluten but with the penalty of greatly reduced stiffness. Former work showed that the brittleness of wheat gluten can also be improved by modifying it with a tri-thiol additive with no penalty of reduced stiffness. However, the cost of the customer designed tri-thiol additive was very high and it was unlikely to make a cost effective material from such an expensive additive. Here we designed a new, inexpensive thiol additive called SHPVA. It was synthesized from polyvinyl alcohol (PVA) through a simple esterification reaction. The mechanical data of the molded wheat gluten/SHPVA material indicated that wheat gluten was toughened by SHPVA. As a control, the wheat gluten/PVA material showed no improvement compared with wheat gluten itself. Several techniques have been used to characterize this novel protein/polymer blend. Differential scanning calorimetric (DSC) study showed two phases in both wheat gluten/PVA and wheat gluten/SHPVA material. However, scanning electron microscope (SEM) pictures indicated that PVA was macroscopically separated from wheat gluten, while wheat gluten/SHPVA had a homogeneous look. The phase image from the atomic force microscope (AFM) gave interesting contrast based on the difference in the mechanical properties of these two phases. The biodegradation behavior of these protein/polymer blends was examined in soil. SHPVA was not degraded in the time period of the experiment. Wheat gluten/SHPVA degraded slower than wheat gluten. We also developed some other interesting material systems based on wheat gluten, including the

  13. Viscosity studies of water based magnetite nanofluids

    SciTech Connect

    Anu, K.; Hemalatha, J.

    2016-05-23

    Magnetite nanofluids of various concentrations have been synthesized through co-precipitation method. The structural and topographical studies made with the X-Ray Diffractometer and Atomic Force Microscope are presented in this paper. The density and viscosity studies for the ferrofluids of various concentrations have been made at room temperature. The experimental viscosities are compared with theoretical values obtained from Einstein, Batchelor and Wang models. An attempt to modify the Rosensweig model is made and the modified Rosensweig equation is reported. In addition, new empirical correlation is also proposed for predicting viscosity of ferrofluid at various concentrations.

  14. Viscosity studies of water based magnetite nanofluids

    NASA Astrophysics Data System (ADS)

    Anu, K.; Hemalatha, J.

    2016-05-01

    Magnetite nanofluids of various concentrations have been synthesized through co-precipitation method. The structural and topographical studies made with the X-Ray Diffractometer and Atomic Force Microscope are presented in this paper. The density and viscosity studies for the ferrofluids of various concentrations have been made at room temperature. The experimental viscosities are compared with theoretical values obtained from Einstein, Batchelor and Wang models. An attempt to modify the Rosensweig model is made and the modified Rosensweig equation is reported. In addition, new empirical correlation is also proposed for predicting viscosity of ferrofluid at various concentrations.

  15. Adrenocorticotrophic Hormone Levels in Ground Based Studies

    NASA Technical Reports Server (NTRS)

    Campbell, B. O.

    1972-01-01

    Baseline values of immunoreactive ACTH were established in the normal healthy adult. Normal levels of ACTH secretion were determined for both the male and the female in circulating plasma and serum. The data obtained in these studies are particularly significant in that the sampling was carefully controlled; only healthy employed individuals of both sexes were tested in a routine work situation that would not be considered conducive to stress. It has been found that alterations in the classically described circadian rhythm of ACTH secretion can occur when activities (such as work/rest cycles) are imposed on the individual studied. These changes can be demonstrated even when there is no appreciable change noted in the rhythm of hydrocortisone secretion.

  16. Study of Capillary-Based Gaseous Detectors

    NASA Astrophysics Data System (ADS)

    Iacobaeus, C.; Francke, T.; Danielsson, M.; Ostling, J.; Peskov, V.

    2004-06-01

    We have studied gain vs. voltage characteristics and position resolutions of multistep capillary plates (two or three capillary plates operating in a cascade), as well as capillary plates operating in a mode when the main amplification occurs between plates or between the capillary plate and the readout plate (parallel plate amplification mode). Results of these studies demonstrated that in the parallel-plate amplification mode one can reach both high gains (>100000) and good position resolutions (~100 micro meter) even with a single step arrangement. It offers a compact amplification structure, which can be used in many applications. For example, in preliminary tests we succeeded to combine it with a photocathode and use it as a position sensitive gaseous photomultiplier. CsI coated capillary plates could also be used as a high position resolution and high rate X-ray converter.

  17. Study on aluminium-based single films.

    PubMed

    Vinod Kumar, G S; García-Moreno, F; Babcsán, N; Brothers, A H; Murty, B S; Banhart, J

    2007-12-28

    In the present paper the authors studied isolated metallic films made from the same material used for making metallic foams, and then characterised their properties. Metal films were made from a liquid aluminium alloy reinforced with ceramic particles of known concentration. Melts without such particles were also investigated. It is shown that stable films could not be made from Al-Si alloy having no particles, and just extremely thin and fragile films could be made from commercially-pure Al. In contrast, aluminium alloys containing particles such as SiC and TiB(2) allowed pulling thin, stable films, which did not rupture. Significant thinning of films was observed when the particle concentration in the melt decreased. By in situ X-ray monitoring of liquid films during pulling, film thickness and drainage effects within the liquid film could be studied. The morphology and microstructure of films was characterised after solidification. Our work shows that the question of how foams are stabilised can be studied using a simplified system such as a film, instead of having to deal with the multitude of different structural elements present in a foam.

  18. [Study on thermoanalysis-based calamina processing].

    PubMed

    Meng, Xiang-Long; Ma, Jun-Nan; Cui, Nan-Nan; Pin, Yu-Hang; Li, Kun; Zhang, Shuo-Sheng

    2013-12-01

    Thermogravimetry (TG), TG-MS, Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM)-energy dispersive spectrometer(EDS) were adopted to investigate the pyrolysis characteristics of calamina. According to the findings of the qualitative and quantitative studies on the changes in the content of relevant elements, the whole shape, the functional groups, and the volatile components of calamina before and after being pyrolyzed, the 200-360, 580-750 degrees C were two sensitive temperature ranges related to the changes in effective component during calamina processing. Thermal weight loss was observed for ZnCO3, Zn(OH)2 and ZnCO3-2Zn(OH)2-H2O under 200-360 degrees C and for CaCO3 under 580-750 degrees C. The results of studies on chemical reaction kinetics showed good linear relations. This experiment integrated relevant methods and theories of physical chemistry and science of traditional Chinese medicine processing, and interpretes calamina processing techniques and mechanism, in order to provide a good example for modem studies on other traditional Chinese medicine processing.

  19. Studies on recycled aggregates-based concrete.

    PubMed

    Rakshvir, Major; Barai, Sudhirkumar V

    2006-06-01

    Reduced extraction of raw materials, reduced transportation cost, improved profits, reduced environmental impact and fast-depleting reserves of conventional natural aggregates has necessitated the use of recycling, in order to be able to conserve conventional natural aggregate. In this study various physical and mechanical properties of recycled concrete aggregates were examined. Recycled concrete aggregates are different from natural aggregates and concrete made from them has specific properties. The percentages of recycled concrete aggregates were varied and it was observed that properties such as compressive strength showed a decrease of up to 10% as the percentage of recycled concrete aggregates increased. Water absorption of recycled aggregates was found to be greater than natural aggregates, and this needs to be compensated during mix design.

  20. [Clinical Study of Skull Base Osteomyelitis].

    PubMed

    Ueki, Yushi; Matsuyama, Hiroshi; Morita, Yuka; Takahashi, Kuniyuki; Yamamoto, Yutaka; Takahashi, Sugata

    2015-01-01

    Typical osteomyelitis is reportedly caused by Pseudomonous aeruginosa in elderly diabetic patients after malignant external otitis. Recently, complications have arisen due to the emergence of atypical osteomyelitis. We have experiensed 5 cases of skull base osteomyelitis at our hospital. All patients were male with a mean age of 75.2 years. Four patients had diabetes. Regarding the clinical and radiographic findings, patients 1, 2, and 3 had typical osteomyelitis after malignant external otitis, whereas patients 4 and 5 had atypical osteomyelitis without temporal bone findings. Sample culturing revealed Pseudomonas aeruginosa in 4 cases and Aspergillus in one. Intravenous antibiotics were administered to all patients. Two patients responded positively and survived, while 3 died. Typical osteomyelitis is reportedly caused by P. aeruginosa in elderly diabetic patients after malignant external otitis. Recently, complications have arisen due to the emergence of atypical osteomyelitis. The prognosis of skull base osteomyelitis is still poor in Japan. Early diagnosis and long-term antibiotic administration is required to improve outcome.

  1. 30 WS North Base Wind Study

    NASA Technical Reports Server (NTRS)

    Wheeler, Mark

    2011-01-01

    The 30 Weather Squadron (30 WS) is concerned about strong winds observed at their northern towers without advance warning. They state that terrain influences along the extreme northern fringes of Vandenberg Air Force Base (VAFB) make it difficult for forecasters to issue timely and accurate high wind warnings for northeasterly wind events. These events tend to occur during the winter or early spring when they are under the influence of the Great Basin high pressure weather regime. The Launch Weather Officers (LWOs) have seen these rapid wind increases in the current northern Towers 60, 70 and 71 in excess of their 35 kt operational warning threshold. For this task, the 30 WS requested the Applied Meteorology Unit (AMU) analyze data from days when these towers reported winds in excess of 35 kt and determine if there were any precursors in the observations that would allow the LWOs to better forecast and warn their operational customers for these wind events. The 30 WS provided wind tower data for the cool season (October - March) from the period January 2004-March 20 IO. The AMU decoded and evaluated the wind tower data for 66 days identified by the 30 WS as having high-wind events. Out of the 66 event days, only 30 had wind speed observations of > or =35 kt from at least one of the three northern towers. The AMU analyzed surface and upper air charts to determine the synoptic conditions for each event day along with tower peak wind speed and direction time series and wind rose charts for all 30 event days. The analysis revealed a trend on all event days in which the tower winds shifted to the northeast for a period of time before the first recorded > or =35 kt wind speed. The time periods for the 30 event days ranged from 20 minutes to several hours, with a median value of 110 minutes. This trend, if monitored, could give the 30 WS forecasters a precursor to assist in issuing an operational warning before a high wind event occurs. The AMU recommends developing a

  2. Subdural haemorrhages in infants: population based study

    PubMed Central

    Jayawant, S; Rawlinson, A; Gibbon, F; Price, J; Schulte, J; Sharples, P; Sibert, J R; Kemp, A M

    1998-01-01

    Objectives To identify the incidence, clinical outcome, and associated factors of subdural haemorrhage in children under 2 years of age, and to determine how such cases were investigated and how many were due to child abuse. Design Population based case series. Setting South Wales and south west England. Subjects Children under 2 years of age who had a subdural haemorrhage. We excluded neonates who developed subdural haemorrhage during their stay on a neonatal unit and infants who developed a subdural haemorrhage after infection or neurosurgical intervention. Main outcome measures Incidence and clinical outcome of subdural haemorrhage in infants, the number of cases caused by child abuse, the investigations such children received, and associated risk factors. Results Thirty three children (23 boys and 10 girls) were identified with subdural haemorrhage. The incidence was 12.8/100 000 children/year (95% confidence interval 5.4 to 20.2). Twenty eight cases (85%) were under 1 year of age. The incidence of subdural haemorrhage in children under 1 year of age was 21.0/100 000 children/year and was therefore higher than in the older children. The clinical outcome was poor: nine infants died and 15 had profound disability. Only 22 infants had the basic investigations of a full blood count, coagulation screen, computed tomography or magnetic resonance imaging, skeletal survey or bone scan, and ophthalmological examination. In retrospect, 27 cases (82%) were highly suggestive of abuse. Conclusion Subdural haemorrhage is common in infancy and carries a poor prognosis; three quarters of such infants die or have profound disability. Most cases are due to child abuse, but in a few the cause is unknown. Some children with subdural haemorrhage do not undergo appropriate investigations. We believe the clinical investigation of such children should include a full multidisciplinary social assessment, an ophthalmic examination, a skeletal survey supplemented with a bone scan or a

  3. Study Of Heating Of The Base Region Of A Rocket

    NASA Technical Reports Server (NTRS)

    Ascoli, Edward P.; Heiba, Adel A.; Hsu, Yann-Fu; Lagnado, Ronald R.; Lynch, Edward D.; Ungewitter, Ronald J.

    1994-01-01

    Report describes theoretical study of heating in base region of proposed rocket called "NLS 1.5 stage reference vehicle." Study employed approach based on computational fluid dynamics (CFD). Involved numerical simulations of flow field in base region and in main exhaust plume of cluster of six engines with heat shields.

  4. Utilizing Web-Based Case Studies for Cutting-Edge Information Services Issues: A Pilot Study.

    ERIC Educational Resources Information Center

    Harrington, Deborah Lynn; Li, Xiaodong

    2002-01-01

    Reports on a pilot study conducted to determine whether the benefits of the case study method as a training framework for change initiatives in academic libraries could successfully transfer from traditional instruction to a virtual Web-based format. Presents results of a survey that evaluated the study and showed positive feedback. (Author/LRW)

  5. Arts-Based Self-Study: Documenting the Ripple Effect

    ERIC Educational Resources Information Center

    Weber, Sandra

    2014-01-01

    Like all forms of inquiry, arts-based self-study research can have unexpected consequences. Although we may start out with a fairly clear objective, the data we generate through arts-based methods might address other questions that are even more important than the ones we thought to ask initially, and our study might have an impact that extends…

  6. Arts-Based Self-Study: Documenting the Ripple Effect

    ERIC Educational Resources Information Center

    Weber, Sandra

    2014-01-01

    Like all forms of inquiry, arts-based self-study research can have unexpected consequences. Although we may start out with a fairly clear objective, the data we generate through arts-based methods might address other questions that are even more important than the ones we thought to ask initially, and our study might have an impact that extends…

  7. Space station accommodations for lunar base elements: A study

    NASA Technical Reports Server (NTRS)

    Weidman, Deene J.; Cirillo, William; Llewellyn, Charles; Kaszubowski, Martin; Kienlen, E. Michael, Jr.

    1987-01-01

    The results of a study conducted at NASA-LaRC to assess the impact on the space station of accommodating a Manned Lunar Base are documented. Included in the study are assembly activities for all infrastructure components, resupply and operations support for lunar base elements, crew activity requirements, the effect of lunar activities on Cape Kennedy operations, and the effect on space station science missions. Technology needs to prepare for such missions are also defined. Results of the study indicate that the space station can support the manned lunar base missions with the addition of a Fuel Depot Facility and a heavy lift launch vehicle to support the large launch requirements.

  8. Reasons related to adherence in community-based field studies.

    PubMed

    Atwood, J R; Haase, J; Rees-McGee, S; Blackwell, G; Giordano, L; Earnest, D; Alberts, D; Sheehan, E; Benedict, J; Aickin, M

    1992-06-01

    This study identified participants' reasons for good, marginal or poor adherence, or withdrawing from community-based clinical studies using a dietary and/or drug intervention. Adults aged 48-75 years participated in one of three studies related to decreasing colon polyp recurrence. Qualitative data from progress notes (N = 675) and end-of-study evaluations (N = 87) were coded using constant comparative analysis with 100% content validity panel agreement. Most common reasons for non-adherence were barriers such as side-effects, interference with vacation plans, unrelated illness, forgetting and competing outside stressors. Participation motivators were benefits such as altruism, medical benefits, free service and staff rapport. Findings supported the Health Behavior in Cancer Prevention model-based approach to adherence interventions and provided directions for adherence promotion in future community-based clinical studies.

  9. US EPA Base Study Standard Operating Procedure for Building Recruiting

    EPA Pesticide Factsheets

    Building recruiting for the BASE study is defined by a random selection of buildings within cities of population exceeding 100,000 inhabitants and located in selected climatic regions of the United States.

  10. Integrated genome-based studies of Shewanella Ecophysiology

    SciTech Connect

    Tiedje, James M.; Konstantinidis, Kostas; Worden, Mark

    2014-01-08

    The aim of the work reported is to study Shewanella population genomics, and to understand the evolution, ecophysiology, and speciation of Shewanella. The tasks supporting this aim are: to study genetic and ecophysiological bases defining the core and diversification of Shewanella species; to determine gene content patterns along redox gradients; and to Investigate the evolutionary processes, patterns and mechanisms of Shewanella.

  11. The Study of Project-Based Learning in Preservice Teachers

    ERIC Educational Resources Information Center

    Anderson, Ashley Ann

    2016-01-01

    Project-based learning (PBL) is a teaching approach where students engage in the investigation of real-world problems through their inquiries. Studies found considerable support for PBL on student performance and improvement in grades K-12 and at the collegiate level. However, fewer studies have examined the effects of PBL at the collegiate level…

  12. A Qualitative Study of College-Based Peace Education Programs

    ERIC Educational Resources Information Center

    Boudreau, Will

    2017-01-01

    The purpose of this exploratory research study was to examine the perceptions of seven northeast United States, college-based, Peace Education program directors regarding their respective programs' characteristics and the challenges they face. This qualitative study was designed to fill a gap in the literature by examining the perceptions of…

  13. Arts-Based Learning and Leadership Development: A Case Study

    ERIC Educational Resources Information Center

    Brenner, Michael Yoel

    2010-01-01

    This qualitative case study was designed to explore how participants in an arts-based leadership development program learned to draw on their right brain capabilities in order to develop the creative competencies required to solve complex modern-day problems in new and different ways. The rationale for this study emerges from the researcher's…

  14. The Study of Project-Based Learning in Preservice Teachers

    ERIC Educational Resources Information Center

    Anderson, Ashley Ann

    2016-01-01

    Project-based learning (PBL) is a teaching approach where students engage in the investigation of real-world problems through their inquiries. Studies found considerable support for PBL on student performance and improvement in grades K-12 and at the collegiate level. However, fewer studies have examined the effects of PBL at the collegiate level…

  15. Thirty Years of School Based Curriculum Development: A Case Study.

    ERIC Educational Resources Information Center

    Ben-Peretz, Miriam; Dor, Ben Zion

    A study of one school's involvement in school-based curriculum development (SBCD) for nearly 30 years provided researchers with information on the factors affecting the success of SBCD programs. The school studied serves 3,500 students in 12 grades at several sites in an Israeli city. Following interviews with faculty members, the researchers…

  16. An Empirical Study for Impacts of Measurement Errors on EHR based Association Studies

    PubMed Central

    Duan, Rui; Cao, Ming; Wu, Yonghui; Huang, Jing; Denny, Joshua C; Xu, Hua; Chen, Yong

    2016-01-01

    Over the last decade, Electronic Health Records (EHR) systems have been increasingly implemented at US hospitals. Despite their great potential, the complex and uneven nature of clinical documentation and data quality brings additional challenges for analyzing EHR data. A critical challenge is the information bias due to the measurement errors in outcome and covariates. We conducted empirical studies to quantify the impacts of the information bias on association study. Specifically, we designed our simulation studies based on the characteristics of the Electronic Medical Records and Genomics (eMERGE) Network. Through simulation studies, we quantified the loss of power due to misclassifications in case ascertainment and measurement errors in covariate status extraction, with respect to different levels of misclassification rates, disease prevalence, and covariate frequencies. These empirical findings can inform investigators for better understanding of the potential power loss due to misclassification and measurement errors under a variety of conditions in EHR based association studies. PMID:28269935

  17. StudySearch: a web-based application for posting and searching clinical research studies.

    PubMed

    Gonsenhauser, Blair; Hallarn, Rose; Carpenter, Daniel; Para, Michael F; Reider, Carson R

    2016-03-01

    Participant accrual into research studies is critical to advancing clinical and translational research to clinical care. Without sufficient recruitment, the purpose of any research study cannot be realized; yet, low recruitment and enrollment of participants persist. StudySearch is a web-based application designed to provide an easily readable, publicly accessible, and searchable listing of IRB-approved protocols that are accruing study participants. The Regulatory, Recruitment and Biomedical Informatics Cores of the Center for Clinical and Translational Science (CCTS) at The Ohio State University developed this research study posting platform. Postings include basic descriptive information: study title, purpose of the study, eligibility criteria and study personnel contact information. Language concerning benefits and/or inducements is not included; therefore, while IRB approval for a study to be listed on StudySearch is required, IRB approval of the posted language is not. Studies are listed by one of two methods; one automated and one manual: (1). Studies registered on ClinicalTrials.gov are automatically downloaded once a month; or (2). Studies are submitted directly by researchers to the CCTS Regulatory Core staff. In either case, final language is a result of an iterative process between researchers and CCTS staff. Deployed in January 2011 at OSU, this application has grown to approximately 200 studies currently posted and 1500 unique visitors per month. Locally, StudySearch is part of the CCTS recruitment toolkit. Features continue to be modified to better accommodate user behaviors. Nationally, this open source application is available for use. Copyright © 2016 American Federation for Medical Research.

  18. StudySearch: a web-based application for posting and searching clinical research studies

    PubMed Central

    Gonsenhauser, Blair; Hallarn, Rose; Carpenter, Daniel; Para, Michael F; Reider, Carson R

    2016-01-01

    Participant accrual into research studies is critical to advancing clinical and translational research to clinical care. Without sufficient recruitment, the purpose of any research study cannot be realized; yet, low recruitment and enrollment of participants persist. StudySearch is a web-based application designed to provide an easily readable, publicly accessible, and searchable listing of IRB-approved protocols that are accruing study participants. The Regulatory, Recruitment and Biomedical Informatics Cores of the Center for Clinical and Translational Science (CCTS) at The Ohio State University developed this research study posting platform. Postings include basic descriptive information: study title, purpose of the study, eligibility criteria and study personnel contact information. Language concerning benefits and/or inducements is not included; therefore, while IRB approval for a study to be listed on StudySearch is required, IRB approval of the posted language is not. Studies are listed by one of two methods; one automated and one manual: (1). Studies registered on ClinicalTrials.gov are automatically downloaded once a month; or (2). Studies are submitted directly by researchers to the CCTS Regulatory Core staff. In either case, final language is a result of an iterative process between researchers and CCTS staff. Deployed in January 2011 at OSU, this application has grown to approximately 200 studies currently posted and 1500 unique visitors per month. Locally, StudySearch is part of the CCTS recruitment toolkit. Features continue to be modified to better accommodate user behaviors. Nationally, this open source application is available for use. PMID:26912012

  19. Using Case Studies in Calculus-based Physics

    NASA Astrophysics Data System (ADS)

    Katz, Debora M.

    2006-12-01

    Do your students believe that the physics only works in your classroom or laboratory? Or do they see that physics underlies their everyday experience? Case studies in physics help students connect physics principles to their everyday experience. For decades, case studies have been used to teach law, medicine and biology, but they are rarely used in physics. I am working on a calculus-based physics textbook for scientists and engineers. Case studies are woven into each chapter. Stop by and get a case study to test out in your classroom. I would love to get your feedback.

  20. Image based 3D city modeling : Comparative study

    NASA Astrophysics Data System (ADS)

    Singh, S. P.; Jain, K.; Mandla, V. R.

    2014-06-01

    3D city model is a digital representation of the Earth's surface and it's related objects such as building, tree, vegetation, and some manmade feature belonging to urban area. The demand of 3D city modeling is increasing rapidly for various engineering and non-engineering applications. Generally four main image based approaches were used for virtual 3D city models generation. In first approach, researchers were used Sketch based modeling, second method is Procedural grammar based modeling, third approach is Close range photogrammetry based modeling and fourth approach is mainly based on Computer Vision techniques. SketchUp, CityEngine, Photomodeler and Agisoft Photoscan are the main softwares to represent these approaches respectively. These softwares have different approaches & methods suitable for image based 3D city modeling. Literature study shows that till date, there is no complete such type of comparative study available to create complete 3D city model by using images. This paper gives a comparative assessment of these four image based 3D modeling approaches. This comparative study is mainly based on data acquisition methods, data processing techniques and output 3D model products. For this research work, study area is the campus of civil engineering department, Indian Institute of Technology, Roorkee (India). This 3D campus acts as a prototype for city. This study also explains various governing parameters, factors and work experiences. This research work also gives a brief introduction, strengths and weakness of these four image based techniques. Some personal comment is also given as what can do or what can't do from these softwares. At the last, this study shows; it concluded that, each and every software has some advantages and limitations. Choice of software depends on user requirements of 3D project. For normal visualization project, SketchUp software is a good option. For 3D documentation record, Photomodeler gives good result. For Large city

  1. The Inclusion of African-American Study Participants in Web-Based Research Studies: Viewpoint

    PubMed Central

    Harker, Laura; Arriola, Kimberly R. Jacob

    2016-01-01

    The use of Web-based methods for research recruitment and intervention delivery has greatly increased as Internet usage continues to grow. These Internet-based strategies allow for researchers to quickly reach more people. African-Americans are underrepresented in health research studies. Due to this, African-Americans get less benefit from important research that could address the disproportionate health outcomes they face. Web-based research studies are one promising way to engage more African-Americans and build trust with the African-American community. With African-Americans’ increasing access to the Internet using mobile phones and other mobile phone technologies, we advocate for efforts to increase the representation of African-Americans in research studies by using the Internet as a recruitment tool and conclude with recommendations that support this goal. PMID:27334683

  2. Methodological Aspects in Studies Based on Clinical Routine Data.

    PubMed

    Kennes, Lieven Nils

    2017-09-12

    Randomized controlled clinical trials are regarded as the gold standard for comparing different clinical interventions, but generally their conduct is operationally cumbersome, time-consuming, and expensive. Studies and investigations based on clinical routine data on the contrary utilize existing data acquired under real-life conditions and are increasingly popular among practitioners. In this paper, methodological aspects of studies based on clinical routine data are discussed. Important limitations and considerations as well as unique strengths of these types of studies are indicated and exemplarily demonstrated in a recent real-case study based on clinical routine data. In addition two simulation studies reveal the impact of bias in studies based on clinical routine data on the type I error rate and false decision rate in favor of the inferior intervention. It is concluded that correctly analyzing clinical routine data yields a valuable addition to clinical research; however, as a result of a lack of statistical foundation, internal validity, and comparability, generalizing results and inferring properties derived from clinical routine data to all patients of interest has to be considered with extreme caution. Grünenthal GmbH.

  3. An entropy-based statistic for genomewide association studies.

    PubMed

    Zhao, Jinying; Boerwinkle, Eric; Xiong, Momiao

    2005-07-01

    Efficient genotyping methods and the availability of a large collection of single-nucleotide polymorphisms provide valuable tools for genetic studies of human disease. The standard chi2 statistic for case-control studies, which uses a linear function of allele frequencies, has limited power when the number of marker loci is large. We introduce a novel test statistic for genetic association studies that uses Shannon entropy and a nonlinear function of allele frequencies to amplify the differences in allele and haplotype frequencies to maintain statistical power with large numbers of marker loci. We investigate the relationship between the entropy-based test statistic and the standard chi2 statistic and show that, in most cases, the power of the entropy-based statistic is greater than that of the standard chi2 statistic. The distribution of the entropy-based statistic and the type I error rates are validated using simulation studies. Finally, we apply the new entropy-based test statistic to two real data sets, one for the COMT gene and schizophrenia and one for the MMP-2 gene and esophageal carcinoma, to evaluate the performance of the new method for genetic association studies. The results show that the entropy-based statistic obtained smaller P values than did the standard chi2 statistic.

  4. Population-based case-control association studies.

    PubMed

    Hancock, Dana B; Scott, William K

    2012-07-01

    This unit provides an overview of the design and analysis of population-based case-control studies of genetic risk factors for complex disease. Considerations specific to genetic studies are emphasized. The unit reviews basic study designs differentiating case-control studies from others, presents different genetic association strategies (candidate gene, genome-wide association, and high-throughput sequencing), introduces basic methods of statistical analysis for case-control data and approaches to combining case-control studies, and discusses measures of association and impact. Admixed populations, controlling for confounding (including population stratification), consideration of multiple loci and environmental risk factors, and complementary analyses of haplotypes, genes, and pathways are briefly discussed. Readers are referred to basic texts on epidemiology for more details on general conduct of case-control studies.

  5. Can We Study Autonomous Driving Comfort in Moving-Base Driving Simulators? A Validation Study.

    PubMed

    Bellem, Hanna; Klüver, Malte; Schrauf, Michael; Schöner, Hans-Peter; Hecht, Heiko; Krems, Josef F

    2017-05-01

    To lay the basis of studying autonomous driving comfort using driving simulators, we assessed the behavioral validity of two moving-base simulator configurations by contrasting them with a test-track setting. With increasing level of automation, driving comfort becomes increasingly important. Simulators provide a safe environment to study perceived comfort in autonomous driving. To date, however, no studies were conducted in relation to comfort in autonomous driving to determine the extent to which results from simulator studies can be transferred to on-road driving conditions. Participants ( N = 72) experienced six differently parameterized lane-change and deceleration maneuvers and subsequently rated the comfort of each scenario. One group of participants experienced the maneuvers on a test-track setting, whereas two other groups experienced them in one of two moving-base simulator configurations. We could demonstrate relative and absolute validity for one of the two simulator configurations. Subsequent analyses revealed that the validity of the simulator highly depends on the parameterization of the motion system. Moving-base simulation can be a useful research tool to study driving comfort in autonomous vehicles. However, our results point at a preference for subunity scaling factors for both lateral and longitudinal motion cues, which might be explained by an underestimation of speed in virtual environments. In line with previous studies, we recommend lateral- and longitudinal-motion scaling factors of approximately 50% to 60% in order to obtain valid results for both active and passive driving tasks.

  6. Review of genotoxicity biomonitoring studies of glyphosate-based formulations

    PubMed Central

    Kier, Larry D.

    2015-01-01

    Abstract Human and environmental genotoxicity biomonitoring studies involving exposure to glyphosate-based formulations (GBFs) were reviewed to complement an earlier review of experimental genotoxicity studies of glyphosate and GBFs. The environmental and most of the human biomonitoring studies were not informative because there was either a very low frequency of GBF exposure or exposure to a large number of pesticides without analysis of specific pesticide effects. One pesticide sprayer biomonitoring study indicated there was not a statistically significant relationship between frequency of GBF exposure reported for the last spraying season and oxidative DNA damage. There were three studies of human populations in regions of GBF aerial spraying. One study found increases for the cytokinesis-block micronucleus endpoint but these increases did not show statistically significant associations with self-reported spray exposure and were not consistent with application rates. A second study found increases for the blood cell comet endpoint at high exposures causing toxicity. However, a follow-up to this study 2 years after spraying did not indicate chromosomal effects. The results of the biomonitoring studies do not contradict an earlier conclusion derived from experimental genotoxicity studies that typical GBFs do not appear to present significant genotoxic risk under normal conditions of human or environmental exposures. PMID:25687244

  7. Review of genotoxicity biomonitoring studies of glyphosate-based formulations.

    PubMed

    Kier, Larry D

    2015-03-01

    Abstract Human and environmental genotoxicity biomonitoring studies involving exposure to glyphosate-based formulations (GBFs) were reviewed to complement an earlier review of experimental genotoxicity studies of glyphosate and GBFs. The environmental and most of the human biomonitoring studies were not informative because there was either a very low frequency of GBF exposure or exposure to a large number of pesticides without analysis of specific pesticide effects. One pesticide sprayer biomonitoring study indicated there was not a statistically significant relationship between frequency of GBF exposure reported for the last spraying season and oxidative DNA damage. There were three studies of human populations in regions of GBF aerial spraying. One study found increases for the cytokinesis-block micronucleus endpoint but these increases did not show statistically significant associations with self-reported spray exposure and were not consistent with application rates. A second study found increases for the blood cell comet endpoint at high exposures causing toxicity. However, a follow-up to this study 2 years after spraying did not indicate chromosomal effects. The results of the biomonitoring studies do not contradict an earlier conclusion derived from experimental genotoxicity studies that typical GBFs do not appear to present significant genotoxic risk under normal conditions of human or environmental exposures.

  8. Combined thermodynamic study of nickel-base alloys. Progress report

    SciTech Connect

    Brooks, C. R.; Meschter, P. J.

    1981-02-15

    Achievements during this period are the following: (1) initiation of a high-temperature study of the Ni-Ta system using the galvanic cell technique, (2) emf study of high-temperature thermodynamics in the Ni-Mo system, (3) measured heat capacity data on ordered and disordered Ni/sub 4/Mo, (4) heat capacities of Ni and disordered Ni/sub 3/Fe, and (5) computer correlation of thermodynamic and phase diagram data in binary Ni-base alloys. (MOW)

  9. Studies on Gel Electrolyte Based on Nitrile-Butadiene Copolymers

    DTIC Science & Technology

    1993-06-01

    preparation of a hybrid electrolyte, suitable for solid-polymer batteries. Based on the study of ionic conductivity in the presence of LiBF4 of a...lithium salts in different plasticizers showed the highest conductivity for LiBF4 . Conductivity of LiBF4 in different plasticizers decreases in the order...GLASS TRANSITION 53 TEMPERATURE OF VARIOUS NBR COPOLYMERS WITH AND WITHOUT LiBF4 APPENDIX B: ANOMALY IN THE IONIC 63 CONDUCTIVITY-TEMPERATURE STUDIES

  10. Study on resistive wall mode based on plasma response model

    NASA Astrophysics Data System (ADS)

    Liu, Yueqiang

    2006-07-01

    A uniform framework, based on the frequency dependent plasma response model (PRM), is proposed to study the physics and control of the resistive wall mode (RWM). The PRM is constructed, respectively, from the Fitzpatrick-Aydemir model, from a cylindrical theory with multiple RWM, and, finally, from toroidal calculations. Based on the PRM, several important aspects of the RWM physics are studied, including the interplay between active feedback and plasma rotation to stabilize the mode, the efficiency of external versus internal active coils for the mode control and the resonant field amplification effect due to a rotationally damped RWM.

  11. Problem-Based Learning: Case Studies, Experience and Practice. Case Studies of Teaching in Higher Education.

    ERIC Educational Resources Information Center

    Schwartz, Peter, Ed.; Mennin, Stewart, Ed.; Webb, Graham, Ed.

    The case studies in this book consider many of the most important issues perceived and experienced by people who are using or developing problem-based learning (PBL). The book focuses on politics, administration, resources, the roles of teachers, and the effects of PBL on students. The chapters are: (1) "Come and See the Real Thing" (David…

  12. Problem-Based Learning: Case Studies, Experience and Practice. Case Studies of Teaching in Higher Education.

    ERIC Educational Resources Information Center

    Schwartz, Peter, Ed.; Mennin, Stewart, Ed.; Webb, Graham, Ed.

    The case studies in this book consider many of the most important issues perceived and experienced by people who are using or developing problem-based learning (PBL). The book focuses on politics, administration, resources, the roles of teachers, and the effects of PBL on students. The chapters are: (1) "Come and See the Real Thing" (David…

  13. Systematic review of community-based childhood obesity prevention studies.

    PubMed

    Bleich, Sara N; Segal, Jodi; Wu, Yang; Wilson, Renee; Wang, Youfa

    2013-07-01

    This study systematically reviewed community-based childhood obesity prevention programs in the United States and high-income countries. We searched Medline, Embase, PsychInfo, CINAHL, clinicaltrials.gov, and the Cochrane Library for relevant English-language studies. Studies were eligible if the intervention was primarily implemented in the community setting; had at least 1 year of follow-up after baseline; and compared results from an intervention to a comparison group. Two independent reviewers conducted title scans and abstract reviews and reviewed the full articles to assess eligibility. Each article received a double review for data abstraction. The second reviewer confirmed the first reviewer's data abstraction for completeness and accuracy. Nine community-based studies were included; 5 randomized controlled trials and 4 non-randomized controlled trials. One study was conducted only in the community setting, 3 were conducted in the community and school setting, and 5 were conducted in the community setting in combination with at least 1 other setting such as the home. Desirable changes in BMI or BMI z-score were found in 4 of the 9 studies. Two studies reported significant improvements in behavioral outcomes (1 in physical activity and 1 in vegetable intake). The strength of evidence is moderate that a combined diet and physical activity intervention conducted in the community with a school component is more effective at preventing obesity or overweight. More research and consistent methods are needed to understand the comparative effectiveness of childhood obesity prevention programs in the community setting.

  14. Study of systems and techniques for data base management

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Data management areas were studied to identify pertinent problems and issues that will affect future NASA data users in terms of performance and cost. Specific topics discussed include the identifications of potential NASA data users other than those normally discussed, consideration affecting the clustering of minicomputers, low cost computer system for information retrieval and analysis, the testing of minicomputer based data base management systems, ongoing work related to the use of dedicated systems for data base management, and the problems of data interchange among a community of NASA data users.

  15. Importance of population-based studies in clinical practice

    PubMed Central

    Ronnie, George; Ve, Ramesh Sathyamangalam; Velumuri, Lokapavani; Asokan, Rashima; Vijaya, Lingam

    2011-01-01

    In the last decade, there have been reports on the prevalence of glaucoma from the Vellore Eye Survey, Andhra Pradesh Eye Diseases Survey, Aravind Comprehensive Eye Survey, Chennai Glaucoma Study and West Bengal Glaucoma Study. Population-based studies provide important information regarding the prevalence and risk factors for glaucoma. They also highlight regional differences in the prevalence of various types of glaucoma. It is possible to gather important insights regarding the number of persons affected with glaucoma and the proportion with undiagnosed disease. We reviewed the different population-based studies from India and compare their findings. The lacunae in ophthalmic care that can be inferred from these studies are identified and possible reasons and solutions are discussed. We also discuss the clinical relevance of the various findings, and how it reflects on clinical practice in the country. Since India has a significantly high disease burden, we examine the possibility of population-based screening for disease in the Indian context. PMID:21150021

  16. Adapting Problem-Based Learning to Social Studies Teacher Education.

    ERIC Educational Resources Information Center

    Hughes, Andrew S.; Sears, Alan M.; Clarke, Gerald M.

    1998-01-01

    Describes how Problem-Based Learning (PBL) was adapted for use in social studies teacher education. Reviews the background of PBL as used in professional faculties, and offers curricular justification for its use. Examines difficulties experienced in adapting PBL to teacher education, taking into account perspectives from prospective teachers and…

  17. A Multidisciplinary Osteoporosis Service-Based Action Research Study

    ERIC Educational Resources Information Center

    Whitehead, Dean; Keast, John; Montgomery, Val; Hayman, Sue

    2004-01-01

    Objective: To investigate an existing Trust-based osteoporosis service's preventative activity, determine any issues and problems and use this data to reorganise the service, as part of a National Health Service Executive/Regional Office-commissioned and funded study. Setting: A UK Hospital Trust's Osteoporosis Service. Design & Method: A…

  18. Science-Based Business Studies at Leiden University

    ERIC Educational Resources Information Center

    Jousma, Harmen

    2006-01-01

    The Science Based Business (SBB) programme was established at Leiden University in 2001 in an effort to counter the unidirectional professionalism of students in science studies--not explicitly to meet the needs of business and industry. Nor is SBB a stand-alone Master's programme like the MS/MBA or the PSM in the USA: rather, it is designed to be…

  19. Explorations in Using Arts-Based Self-Study Methods

    ERIC Educational Resources Information Center

    Samaras, Anastasia P.

    2010-01-01

    Research methods courses typically require students to conceptualize, describe, and present their research ideas in writing. In this article, the author describes her exploration in using arts-based techniques for teaching research to support the development of students' self-study research projects. The pedagogical approach emerged from the…

  20. Project-Based Learning in Electronic Technology: A Case Study

    ERIC Educational Resources Information Center

    Li, Li

    2015-01-01

    A case study of project-based learning (PBL) implemented in Tianjin University of Technology and Education is presented. This multidiscipline project is innovated to meet the novel requirements of industry while keeping its traditional effectiveness in driving students to apply knowledge to practice and problem-solving. The implementation of PBL…

  1. Studying the User Experience of a Tablet Based Math Game

    ERIC Educational Resources Information Center

    Kiili, Kristian; Ketamo, Harri; Koivisto, Antti; Finn, Enda

    2014-01-01

    This paper presents the first findings from Math Elements user experience (UX) studies. Math Elements is a game that makes the whole Finnish maths K-2 curriculum (kindergarten and primary school grades 1 and 2) available for players all over the world. The game is based on teachable agent approach, which means that in the game players can teach…

  2. A Multidisciplinary Osteoporosis Service-Based Action Research Study

    ERIC Educational Resources Information Center

    Whitehead, Dean; Keast, John; Montgomery, Val; Hayman, Sue

    2004-01-01

    Objective: To investigate an existing Trust-based osteoporosis service's preventative activity, determine any issues and problems and use this data to reorganise the service, as part of a National Health Service Executive/Regional Office-commissioned and funded study. Setting: A UK Hospital Trust's Osteoporosis Service. Design & Method: A…

  3. Science-Based Business Studies at Leiden University

    ERIC Educational Resources Information Center

    Jousma, Harmen

    2006-01-01

    The Science Based Business (SBB) programme was established at Leiden University in 2001 in an effort to counter the unidirectional professionalism of students in science studies--not explicitly to meet the needs of business and industry. Nor is SBB a stand-alone Master's programme like the MS/MBA or the PSM in the USA: rather, it is designed to be…

  4. Preliminary study on chicken feather protein-based wood adhesives

    Treesearch

    Zehui Jiang; Daochun Qin; Chung-Yun Hse; Monlin Kuo; Zhaohui Luo; Ge Wang; Yan Yu

    2008-01-01

    The objective of this preliminary study was to partially replace phenol in the synthesis of phenol-formaldehyde resin with feather protein. Feather protein–based resins, which contained one part feather protein and two parts phenol, were formulated under the conditions of two feather protein hydrolysis methods (with and without presence of phenol during...

  5. Discourse-Based Language Intervention: An Efficacy Study.

    ERIC Educational Resources Information Center

    Skarakis-Doyle, Elizabeth; Murphy, Lisa

    1995-01-01

    This study of a 5-year-old girl with sensorineural hearing loss examined the effect of supplementing a pragmatically based procedure of focused stimulation with structured opportunities for verbal practice using vertical constructions. Results indicated that focused stimulation was an effective treatment procedure, especially when enhanced by the…

  6. [The study of noninvasive ventilator impeller based on ANSYS].

    PubMed

    Hu, Zhaoyan; Lu, Pan; Xie, Haiming; Zhou, Yaxu

    2011-06-01

    An impeller plays a significant role in the non-invasive ventilator. This paper shows a model of impeller for noninvasive ventilator established with the software Solidworks. The model was studied for feasibility based on ANSYS. Then stress and strain of the impeller were discussed under the external loads. The results of the analysis provided verification for the reliable design of impellers.

  7. Xiaoxuming decoction and stroke: a literature-based study.

    PubMed

    Zhu, Xin-Hong; Chen, Su-Yun; Gao, Tian-Ming

    2002-06-01

    Xiaoxuming decoction, an ancient traditional Chinese medical prescription for treatment of stroke, has somehow lost its clinical application since Tang Dynasty. Based on the historic record of this prescription, mechanisms of composition and clinical and experimental studies, the authors attempt to evaluate the standing of Xiaoxuming decoction as a remedy for stroke.

  8. Studying the User Experience of a Tablet Based Math Game

    ERIC Educational Resources Information Center

    Kiili, Kristian; Ketamo, Harri; Koivisto, Antti; Finn, Enda

    2014-01-01

    This paper presents the first findings from Math Elements user experience (UX) studies. Math Elements is a game that makes the whole Finnish maths K-2 curriculum (kindergarten and primary school grades 1 and 2) available for players all over the world. The game is based on teachable agent approach, which means that in the game players can teach…

  9. Project-Based Learning in Electronic Technology: A Case Study

    ERIC Educational Resources Information Center

    Li, Li

    2015-01-01

    A case study of project-based learning (PBL) implemented in Tianjin University of Technology and Education is presented. This multidiscipline project is innovated to meet the novel requirements of industry while keeping its traditional effectiveness in driving students to apply knowledge to practice and problem-solving. The implementation of PBL…

  10. A Usability Study of Interactive Web-Based Modules

    ERIC Educational Resources Information Center

    Girard, Tulay; Pinar, Musa

    2011-01-01

    This research advances the understanding of the usability of marketing case study modules in the area of interactive web-based technologies through the assignment of seven interactive case modules in a Principles of Marketing course. The case modules were provided for marketing students by the publisher, McGraw Hill Irwin, of the…

  11. Ontology-Based Federated Data Access to Human Studies Information

    PubMed Central

    Sim, Ida; Carini, Simona; Tu, Samson W.; Detwiler, Landon T.; Brinkley, James; Mollah, Shamim A.; Burke, Karl; Lehmann, Harold P.; Chakraborty, Swati; Wittkowski, Knut M.; Pollock, Brad H.; Johnson, Thomas M.; Huser, Vojtech

    2012-01-01

    Human studies are one of the most valuable sources of knowledge in biomedical research, but data about their design and results are currently widely dispersed in siloed systems. Federation of these data is needed to facilitate large-scale data analysis to realize the goals of evidence-based medicine. The Human Studies Database project has developed an informatics infrastructure for federated query of human studies databases, using a generalizable approach to ontology-based data access. Our approach has three main components. First, the Ontology of Clinical Research (OCRe) provides the reference semantics. Second, a data model, automatically derived from OCRe into XSD, maintains semantic synchrony of the underlying representations while facilitating data acquisition using common XML technologies. Finally, the Query Integrator issues queries distributed over the data, OCRe, and other ontologies such as SNOMED in BioPortal. We report on a demonstration of this infrastructure on data acquired from institutional systems and from ClinicalTrials.gov. PMID:23304360

  12. Recent developments in microfluidics-based chemotaxis studies.

    PubMed

    Wu, Jiandong; Wu, Xun; Lin, Francis

    2013-07-07

    Microfluidic devices can better control cellular microenvironments compared to conventional cell migration assays. Over the past few years, microfluidics-based chemotaxis studies showed a rapid growth. New strategies were developed to explore cell migration in manipulated chemical gradients. In addition to expanding the use of microfluidic devices for a broader range of cell types, microfluidic devices were used to study cell migration and chemotaxis in complex environments. Furthermore, high-throughput microfluidic chemotaxis devices and integrated microfluidic chemotaxis systems were developed for medical and commercial applications. In this article, we review recent developments in microfluidics-based chemotaxis studies and discuss the new trends in this field observed over the past few years.

  13. Measurement of Adults’ Sedentary Time in Population-Based Studies

    PubMed Central

    Healy, Genevieve N.; Clark, Bronwyn K.; Winkler, Elisabeth A.H.; Gardiner, Paul A.; Brown, Wendy J.; Matthews, Charles E.

    2011-01-01

    Sedentary time (too much sitting) is increasingly being recognized as a distinct health risk behavior. This paper reviews the reliability and validity of self-reported and device-based sedentary time measures and provides recommendations for their use in population-based studies. The focus is on instruments that have been used in free-living, population-based research in adults. Data from the 2003–2006 National Health and Nutrition Examination Survey are utilized to compare the descriptive epidemiology of sedentary time that arises from the use of different sedentary time measures. A key recommendation from this review is that, wherever possible, population-based monitoring of sedentary time should incorporate both self-reported measures (to capture important domain- and behavior-specific sedentary time information) and device-based measures (to measure both total sedentary time and patterns of sedentary time accumulation). PMID:21767730

  14. A comparison of gastroenteritis in a general practice-based study and a community-based study.

    PubMed Central

    de Wit, M. A.; Kortbeek, L. M.; Koopmans, M. P.; de Jager, C. J.; Wannet, W. J.; Bartelds, A. I.; van Duynhoven, Y. T.

    2001-01-01

    We compared gastroenteritis cases that consulted a general practitioner (GP) with those who did not in a community-based study and also with those in a GP-based study. We aimed to identify factors associated with consultation, and with inclusion of cases by GPs, and secondly to study the effects on the frequency of detection of pathogens. Furthermore, we estimated the under-ascertainment by GPs. Both studies were performed in The Netherlands in the same population in an overlapping time-period. Overall, 5% of community cases consulted a GP. Cases who consulted suffered from more severe episodes than non-consulting cases. Inclusion of cases by GPs, instead of a study team, caused a selection of more severe cases with more chronic symptoms. When extrapolating data from GP-based studies, it should be taken into account that, in general practice, gastroenteritis due to bacteria and Giardia lamblia is a relatively large proportion of that in the community and gastroenteritis due to Norwalk-like viruses is a relatively small proportion. The incidence of gastroenteritis in general practices was estimated between 14 and 35 per 1000 person years. PMID:11811870

  15. Epidemiological study of prostate cancer (EPICAP): a population-based case-control study in France.

    PubMed

    Menegaux, Florence; Anger, Antoinette; Randrianasolo, Hasina; Mulot, Claire; Laurent-Puig, Pierre; Iborra, François; Bringer, Jean-Pierre; Leizour, Benoit; Thuret, Rodolphe; Lamy, Pierre-Jean; Rébillard, Xavier; Trétarre, Brigitte

    2014-02-19

    Prostate cancer is the most common cancer in male in most Western countries, including France. Despite a significant morbidity and mortality to a lesser extent, the etiology of prostate cancer remains largely unknown. Indeed, the only well-established risk factors to date are age, ethnicity and a family history of prostate cancer. We present, here, the rationale and design of the EPIdemiological study of Prostate CAncer (EPICAP), a population-based case-control study specifically designed to investigate the role of environmental and genetic factors in prostate cancer. The EPICAP study will particularly focused on the role of circadian disruption, chronic inflammation, hormonal and metabolic factors in the occurrence of prostate cancer. EPICAP is a population-based case-control study conducted in the département of Hérault in France. Eligible cases are all cases of prostate cancers newly diagnosed in 2012-2013 in men less than 75 years old and residing in the département of Hérault at the time of diagnosis. Controls are men of the same age as the cases and living in the département of Hérault, recruited in the general population.The sample will include a total of 1000 incident cases of prostate cancer and 1000 population-based controls over a 3-year period (2012-2014).The cases and controls are face-to-face interviewed using a standardized computed assisted questionnaire. The questions focus primarily on usual socio-demographic characteristics, personal and family medical history, lifestyle, leisure activities, residential and occupational history. Anthropometric measures and biological samples are also collected for cases and controls. The EPICAP study aims to answer key questions in prostate cancer etiology: (1) role of circadian disruption through the study of working hours, chronotype and duration/quality of sleep, (2) role of chronic inflammation and anti-inflammatory drugs, (3) role of hormonal and metabolic factors through a detailed questionnaire, (4

  16. Epidemiological study of prostate cancer (EPICAP): a population-based case–control study in France

    PubMed Central

    2014-01-01

    Background Prostate cancer is the most common cancer in male in most Western countries, including France. Despite a significant morbidity and mortality to a lesser extent, the etiology of prostate cancer remains largely unknown. Indeed, the only well-established risk factors to date are age, ethnicity and a family history of prostate cancer. We present, here, the rationale and design of the EPIdemiological study of Prostate CAncer (EPICAP), a population-based case–control study specifically designed to investigate the role of environmental and genetic factors in prostate cancer. The EPICAP study will particularly focused on the role of circadian disruption, chronic inflammation, hormonal and metabolic factors in the occurrence of prostate cancer. Methods/Design EPICAP is a population-based case–control study conducted in the département of Hérault in France. Eligible cases are all cases of prostate cancers newly diagnosed in 2012-2013 in men less than 75 years old and residing in the département of Hérault at the time of diagnosis. Controls are men of the same age as the cases and living in the département of Hérault, recruited in the general population. The sample will include a total of 1000 incident cases of prostate cancer and 1000 population-based controls over a 3-year period (2012-2014). The cases and controls are face-to-face interviewed using a standardized computed assisted questionnaire. The questions focus primarily on usual socio-demographic characteristics, personal and family medical history, lifestyle, leisure activities, residential and occupational history. Anthropometric measures and biological samples are also collected for cases and controls. Discussion The EPICAP study aims to answer key questions in prostate cancer etiology: (1) role of circadian disruption through the study of working hours, chronotype and duration/quality of sleep, (2) role of chronic inflammation and anti-inflammatory drugs, (3) role of hormonal and metabolic

  17. Mediterranean diet and telomere length in Nurses' Health Study: population based cohort study.

    PubMed

    Crous-Bou, Marta; Fung, Teresa T; Prescott, Jennifer; Julin, Bettina; Du, Mengmeng; Sun, Qi; Rexrode, Kathryn M; Hu, Frank B; De Vivo, Immaculata

    2014-12-02

    To examine whether adherence to the Mediterranean diet was associated with longer telomere length, a biomarker of aging. Population based cohort study. Nurses' Health Study, an ongoing prospective cohort study of 121,700 nurses enrolled in 1976; in 1989-90 a subset of 32,825 women provided blood samples. 4676 disease-free women from nested case-control studies within the Nurses' Health Study with telomere length measured who also completed food frequency questionnaires. Association between relative telomere lengths in peripheral blood leukocytes measured by quantitative real time polymerase chain reaction and Alternate Mediterranean Diet score calculated from self reported dietary data. Greater adherence to the Mediterranean diet was associated with longer telomeres after adjustment for potential confounders. Least squares mean telomere length z scores were -0.038 (SE 0.035) for the lowest Mediterranean diet score groups and 0.072 (0.030) for the highest group (P for trend = 0.004). In this large study, greater adherence to the Mediterranean diet was associated with longer telomeres. These results further support the benefits of adherence to the Mediterranean diet for promoting health and longevity. © Crous-Bou et al 2014.

  18. Vegetation studies on Vandenberg Air Force Base, California

    NASA Technical Reports Server (NTRS)

    Schmalzer, Paul A.; Hickson, Diana E.; Hinkle, C. Ross

    1988-01-01

    Vandenburg Air Force Base, located in coastal central California with an area of 98,400 ac, contains resources of considerable biological significance. Available information on the vegetation and flora of Vandenburg is summarized and new data collected in this project are presented. A bibliography of 621 references dealing with vegetation and related topics related to Vanderburg was compiled from computer and manual literature searches and a review of past studies of the base. A preliminary floristic list of 642 taxa representing 311 genera and 80 families was compiled from past studies and plants identified in the vegetation sampling conducted in this project. Fifty-two special interest plant species are known to occur or were suggested to occur. Vegetation was sampled using permanent plots and transects in all major plant communities including chaparral, Bishop pine forest, tanbark oak forest, annual grassland, oak woodland, coastal sage scrub, purple sage scrub, coastal dune scrub, coastal dunes, box elder riparian woodland, will riparian woodland, freshwater marsh, salt marsh, and seasonal wetlands. Comparison of the new vegetation data to the compostie San Diego State University data does not indicate major changes in most communities since the original study. Recommendations are made for additional studies needed to maintain and extend the environmental data base and for management actions to improve resource protection.

  19. Partial gravity habitat study: With application to lunar base design

    NASA Technical Reports Server (NTRS)

    Capps, Stephen; Lorandos, Jason; Akhidime, Eval; Bunch, Michael; Lund, Denise; Moore, Nathan; Murakawa, Kio; Bell, Larry; Trotti, Guillermo; Neubek, Deb

    1989-01-01

    Comprehensive design requirements associated with designing habitats for humans in a partial gravity environment were investigated and then applied to a lunar base design. Other potential sites for application include planetary surfaces such as Mars, variable gravity research facilities, or a rotating spacecraft. Design requirements for partial gravity environments include: (1) locomotion changes in less than normal Earth gravity; (2) facility design issues, such as interior configuration, module diameter and geometry; and (3) volumetric requirements based on the previous as well as psychological issues involved in prolonged isolation. For application to a Lunar Base, it was necessary to study the exterior architecture and configuration to insure optimum circulation patterns while providing dual egress. Radiation protection issues were addressed to provide a safe and healthy environment for the crew, and finally, the overall site was studied to locate all associated facilities in context with the habitat. Mission planning was not the purpose of this study; therefore, a Lockheed scenario was used as an outline for the Lunar Base application, which was then modified to meet the project needs.

  20. Condition Based Maintenance Technology Impact Study: Assessment Methods, Study Design and Interim Results

    DTIC Science & Technology

    2014-07-01

    capability acquisition projects and collaborative research within The Technical Cooperation Program. Ultimately this study will form a basis for a ‘value...actions based on evidence of need, rather than more traditional usage or time schedules. The promise of CBM is threefold: to extend the useful life ...and reduce the through- life cost of equipment; to improve fleet operational availability and mission effectiveness; and to reduce the maintenance

  1. Invulnerability study of transit network based on complex network

    NASA Astrophysics Data System (ADS)

    Wang, Kui; Fu, Xiufen

    2017-05-01

    In order to ensure the normal operation of urban transit network (abbreviated as UTN) and improve the operating efficiency of UTN, this paper takes UTN of Guangzhou as an example, analyzes the topology characteristics of this transit network, studies the invulnerability of the network under random attack and deliberate attack. The simulation results show that under random attack and under attack based on node degree, continuously removing the number of nodes is almost no effect on network invulnerability, but under attack based on the node betweenness and efficiency, the number of consecutive removed nodes is less, the network invulnerability is worse; Influence on network invulnerability by attack based on node betweenness is more significant than influence on network invulnerability by both random attack and attack based on node degree and efficiency.

  2. Systematic Review of Community-Based Childhood Obesity Prevention Studies

    PubMed Central

    Segal, Jodi; Wu, Yang; Wilson, Renee; Wang, Youfa

    2013-01-01

    OBJECTIVE: This study systematically reviewed community-based childhood obesity prevention programs in the United States and high-income countries. METHODS: We searched Medline, Embase, PsychInfo, CINAHL, clinicaltrials.gov, and the Cochrane Library for relevant English-language studies. Studies were eligible if the intervention was primarily implemented in the community setting; had at least 1 year of follow-up after baseline; and compared results from an intervention to a comparison group. Two independent reviewers conducted title scans and abstract reviews and reviewed the full articles to assess eligibility. Each article received a double review for data abstraction. The second reviewer confirmed the first reviewer’s data abstraction for completeness and accuracy. RESULTS: Nine community-based studies were included; 5 randomized controlled trials and 4 non–randomized controlled trials. One study was conducted only in the community setting, 3 were conducted in the community and school setting, and 5 were conducted in the community setting in combination with at least 1 other setting such as the home. Desirable changes in BMI or BMI z-score were found in 4 of the 9 studies. Two studies reported significant improvements in behavioral outcomes (1 in physical activity and 1 in vegetable intake). CONCLUSIONS: The strength of evidence is moderate that a combined diet and physical activity intervention conducted in the community with a school component is more effective at preventing obesity or overweight. More research and consistent methods are needed to understand the comparative effectiveness of childhood obesity prevention programs in the community setting. PMID:23753099

  3. Family-Based Association Studies for Next-Generation Sequencing

    PubMed Central

    Zhu, Yun; Xiong, Momiao

    2012-01-01

    An individual's disease risk is determined by the compounded action of both common variants, inherited from remote ancestors, that segregated within the population and rare variants, inherited from recent ancestors, that segregated mainly within pedigrees. Next-generation sequencing (NGS) technologies generate high-dimensional data that allow a nearly complete evaluation of genetic variation. Despite their promise, NGS technologies also suffer from remarkable limitations: high error rates, enrichment of rare variants, and a large proportion of missing values, as well as the fact that most current analytical methods are designed for population-based association studies. To meet the analytical challenges raised by NGS, we propose a general framework for sequence-based association studies that can use various types of family and unrelated-individual data sampled from any population structure and a universal procedure that can transform any population-based association test statistic for use in family-based association tests. We develop family-based functional principal-component analysis (FPCA) with or without smoothing, a generalized T2, combined multivariate and collapsing (CMC) method, and single-marker association test statistics. Through intensive simulations, we demonstrate that the family-based smoothed FPCA (SFPCA) has the correct type I error rates and much more power to detect association of (1) common variants, (2) rare variants, (3) both common and rare variants, and (4) variants with opposite directions of effect from other population-based or family-based association analysis methods. The proposed statistics are applied to two data sets with pedigree structures. The results show that the smoothed FPCA has a much smaller p value than other statistics. PMID:22682329

  4. Study of a risk-based piping inspection guideline system.

    PubMed

    Tien, Shiaw-Wen; Hwang, Wen-Tsung; Tsai, Chih-Hung

    2007-02-01

    A risk-based inspection system and a piping inspection guideline model were developed in this study. The research procedure consists of two parts--the building of a risk-based inspection model for piping and the construction of a risk-based piping inspection guideline model. Field visits at the plant were conducted to develop the risk-based inspection and strategic analysis system. A knowledge-based model had been built in accordance with international standards and local government regulations, and the rational unified process was applied for reducing the discrepancy in the development of the models. The models had been designed to analyze damage factors, damage models, and potential damage positions of piping in the petrochemical plants. The purpose of this study was to provide inspection-related personnel with the optimal planning tools for piping inspections, hence, to enable effective predictions of potential piping risks and to enhance the better degree of safety in plant operations that the petrochemical industries can be expected to achieve. A risk analysis was conducted on the piping system of a petrochemical plant. The outcome indicated that most of the risks resulted from a small number of pipelines.

  5. Data needs and data bases for climate studies

    NASA Technical Reports Server (NTRS)

    Matthews, Elaine

    1986-01-01

    Two complementary global digital data bases of vegetation and land use, compiled at 1 deg resolution from published sources for use in climate studies, are discussed. The data bases were implemented, in several individually tailored formulations, in a series of climate related applications including: land-surface prescriptions in three-dimensional general circulation models, global biogeochemical cycles (CO2, methane), critical-area mapping for satellite monitoring of land-cover change, and large-scale remote sensing of surface reflectance. The climate applications are discussed with reference to data needs, and data availability from traditional and remote sensing sources.

  6. Space-Based Gravitational-wave Mission Concept Studies

    NASA Technical Reports Server (NTRS)

    Livas, Jeffrey C.

    2012-01-01

    The LISA Mission Concept has been under study for over two decades as a spacebased gravitational-wave detector capable of observing astrophysical sources in the 0.0001 to 1 Hz band. The concept has consistently received strong recommendations from various review panels based on the expected science, most recently from the US Astr02010 Decadal Review. Budget constraints have led both the US and European Space agencies to search for lower cost options. We report results from the US effort to explore the tradeoffs between mission cost and science return, and in particular a family of mission concepts referred to as SGO (Space-based Gravitational-wave Observatory).

  7. Studying the Cost Effects of The Shrinking Industrial Base

    DTIC Science & Technology

    1993-09-01

    89) Prescrbed by AIM St. Z39-IS 290-102 STUDYING THE COST EFFECTS OF THE SHRINKING INDUSTRIAL BASE Downsizing the Army has the effect of reducing the...dicesarr@tacom.emhl.army.mil INTRODUCTION For cost analysts, one of the most puzzling aspects of the downsizing of the military is the effect of...changes in the size of the defense industrial base on cost. It is common knowledge that the downsizing is having an effect on unit vehicle cost, but there

  8. A Computer-Based System for Studies in Learning

    DTIC Science & Technology

    1974-09-01

    A D/A-000 102 A COMPUTER-BASED SYSTEM FOR STUDIES IN LEARNING Donald K. Centner, el al C a 1 i f o r n i a U n i v e nit v...DvlCUMENTATION PAGE I HEAD INSTRUCTIONS 1 1 Rf P;B’r S ^MBE R Tj GOVT ACCESSION NO 4 Ti T .. E ami f.itnlli- A Computer-Based System for...uuibisEinns D ams Th e views and conclusions contained in this document are those of the authors and should not be interpreted as necessarily

  9. Agent-based modeling: case study in cleavage furrow models.

    PubMed

    Mogilner, Alex; Manhart, Angelika

    2016-11-07

    The number of studies in cell biology in which quantitative models accompany experiments has been growing steadily. Roughly, mathematical and computational techniques of these models can be classified as "differential equation based" (DE) or "agent based" (AB). Recently AB models have started to outnumber DE models, but understanding of AB philosophy and methodology is much less widespread than familiarity with DE techniques. Here we use the history of modeling a fundamental biological problem-positioning of the cleavage furrow in dividing cells-to explain how and why DE and AB models are used. We discuss differences, advantages, and shortcomings of these two approaches.

  10. Complexity analysis of human physiological signals based on case studies

    NASA Astrophysics Data System (ADS)

    Angelova, Maia; Holloway, Philip; Ellis, Jason

    2015-04-01

    This work focuses on methods for investigation of physiological time series based on complexity analysis. It is a part of a wider programme to determine non-invasive markers for healthy ageing. We consider two case studies investigated with actigraphy: (a) sleep and alternations with insomnia, and (b) ageing effects on mobility patterns. We illustrate, using these case studies, the application of fractal analysis to the investigation of regulation patterns and control, and change of physiological function. In the first case study, fractal analysis techniques were implemented to study the correlations present in sleep actigraphy for individuals suffering from acute insomnia in comparison with healthy controls. The aim was to investigate if complexity analysis can detect the onset of adverse health-related events. The subjects with acute insomnia displayed significantly higher levels of complexity, possibly a result of too much activity in the underlying regulatory systems. The second case study considered mobility patterns during night time and their variations with age. It showed that complexity metrics can identify change in physiological function with ageing. Both studies demonstrated that complexity analysis can be used to investigate markers of health, disease and healthy ageing.

  11. Transgenic animal models of neurodegeneration based on human genetic studies

    PubMed Central

    Richie, Christopher T.; Hoffer, Barry J.; Airavaara, Mikko

    2011-01-01

    The identification of genes linked to neurodegenerative diseases such as Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), Huntington's disease (HD) and Parkinson's disease (PD) has led to the development of animal models for studying mechanism and evaluating potential therapies. None of the transgenic models developed based on disease-associated genes have been able to fully recapitulate the behavioral and pathological features of the corresponding disease. However, there has been enormous progress made in identifying potential therapeutic targets and understanding some of the common mechanisms of neurodegeneration. In this review, we will discuss transgenic animal models for AD, ALS, HD and PD that are based on human genetic studies. All of the diseases discussed have active or complete clinical trials for experimental treatments that benefited from transgenic models of the disease. PMID:20931247

  12. Complexity metric based on fraction of penumbra dose - initial study

    NASA Astrophysics Data System (ADS)

    Bäck, A.; Nordström, F.; Gustafsson, M.; Götstedt, J.; Karlsson Hauer, A.

    2017-05-01

    Volumetric modulated arc therapy improve radiotherapy outcome for many patients compared to conventional three dimensional conformal radiotherapy but require a more extensive, most often measurement based, quality assurance. Multi leaf collimator (MLC) aperture-based complexity metrics have been suggested to be used to distinguish complex treatment plans unsuitable for treatment without time consuming measurements. This study introduce a spatially resolved complexity score that correlate to the fraction of penumbra dose and will give information on the spatial distribution and the clinical relevance of the calculated complexity. The complexity metric is described and an initial study on the correlation between the complexity score and the difference between measured and calculated dose for 30 MLC openings is presented. The result of an analysis of the complexity scores were found to correlate to differences between measurements and calculations with a Pearson’s r-value of 0.97.

  13. Optical studies of shock generated transient supersonic base flows

    NASA Technical Reports Server (NTRS)

    Liang, P.-Y.; Bershader, D.; Wray, A.

    1982-01-01

    A shock tube employing interferometric and schlieren techniques is used to study transient base flow phenomena following shock wave passage over two plane bluff bodies: a hemicircular cylinder and a cylinder with the Galileo Jovian probe profile. An attempt is made to understand the physics of transition from transient to steady state flow, and to provide code verification for a study employing the Illiac IV computer. Transient base flow interactions include a series of shock diffraction, regular, and Mach reflections, coupled with boundary layer development, separation, and recompression. Vorticity generation and transport underlie these features. The quantitative verification of the computer code includes comparisons of transient pressure and density fields, near wake geometries, and bow shock standoff distances.

  14. Case Studies in Agnotology-Based Learning (Invited)

    NASA Astrophysics Data System (ADS)

    Cook, J.; Bedford, D. P.; Mandia, S. A.

    2013-12-01

    Agnotology is the study of how and why ignorance or misconceptions exist. While misconceptions are a challenge for educators, they also present an opportunity to improve climate literacy through agnotology-based learning. This involves refutational lessons that challenge misconceptions while teaching scientific concepts. I will summarize two decades of research that find refutational texts are among the most effective forms of reducing misconceptions. I will present case studies in improving climate literacy through agnotology-based learning, both in the college classroom and in public outreach promoted through mainstream and social media. I will also explore how content from the SkepticalScience.com website is being used by educators as a teaching resource. These real-world examples demonstrate effective ways to reduce misperceptions and improve climate literacy.

  15. Problem-based learning in optical engineering studies

    NASA Astrophysics Data System (ADS)

    Voznesenskaya, Anna

    2016-09-01

    Nowadays, the Problem-Based Learning (PBL) is one of the most prospective educational technologies. PBL is based on evaluation of learning outcomes of a student, both professional and personal, instead of traditional evaluation of theoretical knowledge and selective practical skills. Such an approach requires changes in the curricula development. There should be introduced projects (cases) imitating real tasks from the professional life. These cases should include a problem summary with necessary theoretic description, charts, graphs, information sources etc, task to implement and evaluation indicators and criteria. Often these cases are evaluated with the assessment-center method. To motivate students for the given task they could be divided into groups and have a contest. Whilst it looks easy to implement in social, economic or teaching fields PBL is pretty complicated in engineering studies. Examples of cases in the first-cycle optical engineering studies are shown in this paper. Procedures of the PBL implementation and evaluation are described.

  16. Study on the FOG's signal based on wavelet

    NASA Astrophysics Data System (ADS)

    Tang, Ji-qiang; Fang, Jian-cheng; Zhang, Yan-shun

    2006-11-01

    In order to study on the fiber optical gyro (abbreviated as FOG) signal based on wavelet, this paper researches the FOG signal drift model and the properties of wavelet analyzed noise, introduces the wavelet filtering method, wavelet base selection, soft and hard threshold value de-noising algorithm and compulsive filtering based on The Haar wavelet. These threshold value filtering results of both of the soft and of the hard threshold value for the same wavelet base of db4 with the same Donoho threshold values and these results of compulsive filtering based on The Haar wavelet and db4 wavelet are presented also in this paper and then these main conclusions based on foregoing analysis are reached: Larger the resolving scale is, the filtering effect is more perfect. The soft threshold value filtering effect is better than that of the hard threshold value filtering at the cost of calculation when the threshold value is same. The zero shift of the compulsive filtering is least when both the wavelet and the resolving scale are same for these filtering methods. For the compulsive filtering with same wavelets, the filtering effect of Harr is better than that of db4 and the calculation of the former is fewer. Finally the author point out that applying the compulsive filtering with the Harr wavelet base and suitable resolving scale to the signal processing of FOG be helpful for the FOG's design and manufacturing.

  17. Ab initio study of naphtho-homologated DNA bases.

    PubMed

    Vazquez-Mayagoita, Alvaro; Huertas, Oscar; Fuentes-Cabrera, Miguel; Sumpter, Bobby G; Orozco, Modesto; Luque, F Javier

    2008-02-21

    Naphtho-homologated DNA bases have been recently used to build a new type of size-expanded DNA known as yyDNA. We have used theoretical techniques to investigate the structure, tautomeric preferences, base-pairing ability, stacking interactions, and HOMO-LUMO gaps of the naphtho-bases. The structure of these bases is found to be similar to that of the benzo-fused predecessors (y-bases) with respect to the planarity of the aromatic rings and amino groups. Tautomeric studies reveal that the canonical-like forms of naphtho-thymine (yyT) and naphtho-adenine (yyA) are the most stable tautomers, leading to hydrogen-bonded dimers with the corresponding natural nucleobases that mimic the Watson-Crick pairing. However, the canonical-like species of naphtho-guanine (yyG) and naphtho-cytosine (yyC) are not the most stable tautomers, and the most favorable hydrogen-bonded dimers involve wobble-like pairings. The expanded size of the naphtho-bases leads to stacking interactions notably larger than those found for the natural bases, and they should presumably play a dominant contribution in modulating the structure of yyDNA duplexes. Finally, the HOMO-LUMO gap of the naphtho-bases is smaller than that of their benzo-base counterparts, indicating that size-expansion of DNA bases is an efficient way of reducing their HOMO-LUMO gap. These results are examined in light of the available experimental evidence reported for yyT and yyC.

  18. Ab initio Study of Naptho-Homologated DNA Bases

    SciTech Connect

    Sumpter, Bobby G; Vazquez-Mayagoitia, Alvaro; Huertas, Oscar; Fuentes-Cabrera, Miguel A; Orozco, Modesto; Luque, Javier

    2008-01-01

    Naptho-homologated DNA bases have been recently used to build a new type of size expanded DNA known as yyDNA. We have used theoretical techniques to investigate the structure, tautomeric preferences, base-pairing ability, stacking interactions, and HOMO-LUMO gaps of the naptho-bases. The structure of these bases is found to be similar to that of the benzo-fused predecessors (y-bases) with respect to the planarity of the aromatic rings and amino groups. Tautomeric studies reveal that the canonical-like form of naptho-thymine (yyT) and naptho-adenine (yyA) are the most stable tautomers, leading to hydrogen-bonded dimers with the corresponding natural nucleobases that mimic the Watson-Crick pairing. However, the canonical-like species of naptho-guanine (yyG) and naptho-cytosine (yyC) are not the most stable tautomers, and the most favorable hydrogen-bonded dimers involve wobble-like pairings. The expanded size of the naphto-bases leads to stacking interactions notably larger than those found for the natural bases, and they should presumably play a dominant contribution in modulating the structure of yyDNA duplexes. Finally, the HOMO-LUMO gap of the naptho-bases is smaller than that of their benzo-base counterparts, indicating that size-expansion of DNA bases is an efficient way of reducing their HOMO-LUMO gap. These results are examined in light of the available experimental evidence reported for yyT and yyC.

  19. Faith based aviation: An ethnographic study of missionary flights international

    NASA Astrophysics Data System (ADS)

    Cooper, Joseph H.

    The development of faith-based missionary aviation is a post-World War II phenomenon. The war effort demonstrated the value, utility, and global reach of aviation to remote, underdeveloped areas of the world. With the beginnings of a worldwide infrastructure for aviation, Christian aviators realized aviation could increase the range and effectiveness of their efforts to reach the world for Christ (Mellis, 2006). Although individual organizations provide statistical information and data about flight operations there is a lack of external evidence and relevant research literature confirming the scope and value of these faith based aviation organizations and operations. A qualitative, ethnographic study was conducted to document the activities of one faith-based aviation organization to gain an understanding of this little known aspect of civilian aviation. The study was conducted with Missionary Flights International (MFI) of Fort Pierce, FL which has been involved in faith-based, missionary aviation since its inception in 1964. As an aviation organization "MFI strives to offer affiliated missions the kind of efficient service and professionalism expected of an airline operation" (Missionary Flights International, 2013, p.1). MFI is a lifeline for missionaries to Haiti and the Dominican Republic, fulfilling their motto of "Standing in the Gap". MFI provides twice a week service to the island of Hispaniola and the Republic of Haiti. In this in-depth study insight and understanding was gained into the purpose of MFI, their daily routines and operations, and the challenges they face in maintaining their flight services to Haiti. This study provided documentation of the value and utility of such aviation efforts and of the individuals involved in this endeavor.

  20. Study on Privacy Protection Algorithm Based on K-Anonymity

    NASA Astrophysics Data System (ADS)

    FeiFei, Zhao; LiFeng, Dong; Kun, Wang; Yang, Li

    Basing on the study of K-Anonymity algorithm in privacy protection issue, this paper proposed a "Degree Priority" method of visiting Lattice nodes on the generalization tree to improve the performance of K-Anonymity algorithm. This paper also proposed a "Two Times K-anonymity" methods to reduce the information loss in the process of K-Anonymity. Finally, we used experimental results to demonstrate the effectiveness of these methods.

  1. Project-based learning in electronic technology: a case study

    NASA Astrophysics Data System (ADS)

    Li, Li

    2015-09-01

    A case study of project-based learning (PBL) implemented in Tianjin University of Technology and Education is presented. This multidiscipline project is innovated to meet the novel requirements of industry while keeping its traditional effectiveness in driving students to apply knowledge to practice and problem-solving. The implementation of PBL is described with emphasis in relation to the ability cultivation. The feedback from students shows positive support for the innovations.

  2. Halogen bonding: a study based on the electronic charge density.

    PubMed

    Amezaga, Nancy J Martinez; Pamies, Silvana C; Peruchena, Nélida M; Sosa, Gladis L

    2010-01-14

    Density functional theory (DFT) and atoms in molecules theory (AIM) were used to study the characteristic of the noncovalent interactions in complexes formed between Lewis bases (NH(3), H(2)O, and H(2)S) and Lewis acids (ClF, BrF, IF, BrCl, ICl, and IBr). In order to compare halogen and hydrogen bonds interactions, this study included hydrogen complexes formed by some Lewis bases and HF, HCl, and HBr Lewis acids. Ab initio, wave functions were generated at B3LYP/6-311++G(d,p) level with optimized structures at the same level. Criteria based on a topological analysis of the electron density were used in order to characterize the nature of halogen interactions in Lewis complexes. The main purpose of the present work is to provide an answer to the following questions: (a) why can electronegative atoms such as halogens act as bridges between two other electronegative atoms? Can a study based on the electron charge density answer this question? Considering this, we had performed a profound study of halogen complexes in the framework of the AIM theory. A good correlation between the density at the intermolecular bond critical point and the energy interaction was found. We had also explored the concentration and depletion of the charge density, displayed by the Laplacian topology, in the interaction zone and in the X-Y halogen donor bond. From the atomic properties, it was generally observed that the two halogen atoms gain electron population in response to its own intrinsic nature. Because of this fact, both atoms are energetically stabilized.

  3. Studies of Broadband PMN Transducers Based on Nonlinear Models

    DTIC Science & Technology

    1997-10-01

    Studies of Broadband PMN Transducers Based on Nonlinear Models G. Wojcik, J. Mould, D. Tennant, R. Richards†, H. Song, D. Vaughan, N. Abboud‡, D...here is a volume array of high-power, electrostrictive (PMN) flextensionals . Analysis and design of these complex arrays are clearly pushing the limits...finite element mod- eling of an icosahedral array of 12 electrostrictive flextensionals . Behavior of the PMN driver is illustrated with a 1D finite

  4. Market-Based Indian Grid Integration Study Options: Preprint

    SciTech Connect

    Stoltenberg, B.; Clark, K.; Negi, S. K.

    2012-03-01

    The Indian state of Gujarat is forecasting solar and wind generation expansion from 16% to 32% of installed generation capacity by 2015. Some states in India are already experiencing heavy wind power curtailment. Understanding how to integrate variable generation (VG) into the grid is of great interest to local transmission companies and India's Ministry of New and Renewable Energy. This paper describes the nature of a market-based integration study and how this approach, while new to Indian grid operation and planning, is necessary to understand how to operate and expand the grid to best accommodate the expansion of VG. Second, it discusses options in defining a study's scope, such as data granularity, generation modeling, and geographic scope. The paper also explores how Gujarat's method of grid operation and current system reliability will affect how an integration study can be performed.

  5. XPS study of ZnO-based varistor materials

    SciTech Connect

    Kostikov, Yu.P.; Malikov, V.A.; Kuz`mina, E.G.

    1994-06-01

    Many articles are devoted to the study of ZnO-based varistor materials. But an adequate model of the constitution of these materials, describing the entire variety of chemical processes proceeding during their formation, does not yet exist. The absence of such a model and lack of knowledge about the chemistry of these materials lead to the introduction of up to ten dopants in their formulations however, the effect of each of these dopants on the material properties may be unclear. It is possible to resolve this problem only through systematic study of the electronic structure of these materials, of the redox processes which determine the formation of the electronic structure of materials, and of the effect of dopants and impurities on redox processes both directly and through the formation of the ceramic sample microstructure. This work is devoted to the XPS study of zinc oxide doped with cobalt and praseodymium oxides.

  6. Acupuncture points for treating Parkinson's disease based on animal studies.

    PubMed

    Kwon, Sunoh; Seo, Byung-Kwan; Kim, Seungtae

    2016-10-01

    Parkinson's disease (PD) is a well-known neurodegenerative disease caused by dopaminergic cell death in the nigrostriatal pathway. Recent studies have shown that acupuncture can be a potential therapy for the treatment of PD, but it is not clear which acupuncture points (acupoints) play major roles in reliving symptoms of PD. Yanglingquan (GB 34), Zusanli (ST 36), Fengfu (GV 16), Taichong (LR 3), Baihui (GV 20) and Dazhui (GV 14) acupoints have frequently been to investigate the effectiveness and action mechanism of acupuncture for treating PD, but it is not clear why they were selected. This review summarizes the current understanding of the acupoints for PD treatment based on Oriental medicine theories and on the accumulated findings from previous animal studies. The results of this study will be useful to development of a strategy for future research in this field.

  7. Family-based designs for genome-wide association studies.

    PubMed

    Ott, Jurg; Kamatani, Yoichiro; Lathrop, Mark

    2011-06-01

    Association mapping has successfully identified common SNPs associated with many diseases. However, the inability of this class of variation to account for most of the supposed heritability has led to a renewed interest in methods - primarily linkage analysis - to detect rare variants. Family designs allow for control of population stratification, investigations of questions such as parent-of-origin effects and other applications that are imperfectly or not readily addressed in case-control association studies. This article guides readers through the interface between linkage and association analysis, reviews the new methodologies and provides useful guidelines for applications. Just as effective SNP-genotyping tools helped to realize the potential of association studies, next-generation sequencing tools will benefit genetic studies by improving the power of family-based approaches.

  8. The prospects for urban densification: a place-based study

    NASA Astrophysics Data System (ADS)

    Schmidt-Thomé, Kaisa; Haybatollahi, Mohammad; Kyttä, Marketta; Korpi, Jari

    2013-06-01

    Study of the environmental outcomes of urban densification is a highly context-dependent task. Our study shows that collecting and processing place-based survey data by means of the softGIS method is clearly helpful here. With the map-based internet questionnaire each response remains connected to both the physical environment and the everyday life of the respondent. In our study of the Kuninkaankolmio area (located in the Helsinki metropolitan region) the survey data were combined with urban density variables calculated from register-based data on the existing built environment. The regression analysis indicated that the participants in the survey preferred the same density factors for their future residence as they enjoyed in their current neighbourhood. In the second analysis we related the densities of planned infill developments with the interest respondents had shown in these projects. The results show that new and even quite dense infill developments have been found to be rather attractive, with them often being viewed as interesting supplements to the current urban texture. These findings contribute to the ongoing scientific discussion on the feasibility of densification measures and encourage the Kuninkaankolmio planners to proceed, albeit carefully, with the planned infill developments.

  9. Feasibility Study of EO SARs as Opportunity Illuminators in Passive Radars: PAZ-Based Case Study.

    PubMed

    Bárcena-Humanes, Jose-Luis; Gómez-Hoyo, Pedro-José; Jarabo-Amores, Maria-Pilar; Mata-Moya, David; Del-Rey-Maestre, Nerea

    2015-11-17

    Passive radars exploit the signal transmitted by other systems, known as opportunity illuminators (OIs), instead of using their own transmitter. Due to its almost total invulnerability to natural disasters or physical attacks, satellite OIs are of special interest. In this line, a feasibility study of Earth Observation Synthetic Aperture Radar (EO SAR) systems as OIs is carried out taking into consideration signal waveform, availability, bistatic geometry, instrumented coverage area and incident power density. A case study based on the use of PAZ, the first Spanish EO SAR, is presented. PAZ transmitted waveform, operation modes, orbit characteristics and antenna and transmitter parameters are analyzed to estimate potential coverages and resolutions. The study concludes that, due to its working in on-demand operating mode, passive radars based on PAZ-type illuminators can be proposed as complementing tools during the sensor commissioning phase, for system maintenance and for improving its performance by providing additional information about the area of interest and/or increasing the data updating speed, exploiting other sensors during the time PAZ is not available.

  10. Feasibility Study of EO SARs as Opportunity Illuminators in Passive Radars: PAZ-Based Case Study

    PubMed Central

    Bárcena-Humanes, Jose-Luis; Gómez-Hoyo, Pedro-José; Jarabo-Amores, Maria-Pilar; Mata-Moya, David; De-Rey-Maestre, Nerea

    2015-01-01

    Passive radars exploit the signal transmitted by other systems, known as opportunity illuminators (OIs), instead of using their own transmitter. Due to its almost total invulnerability to natural disasters or physical attacks, satellite OIs are of special interest. In this line, a feasibility study of Earth Observation Synthetic Aperture Radar (EO SAR) systems as OIs is carried out taking into consideration signal waveform, availability, bistatic geometry, instrumented coverage area and incident power density. A case study based on the use of PAZ, the first Spanish EO SAR, is presented. PAZ transmitted waveform, operation modes, orbit characteristics and antenna and transmitter parameters are analyzed to estimate potential coverages and resolutions. The study concludes that, due to its working in on-demand operating mode, passive radars based on PAZ-type illuminators can be proposed as complementing tools during the sensor commissioning phase, for system maintenance and for improving its performance by providing additional information about the area of interest and/or increasing the data updating speed, exploiting other sensors during the time PAZ is not available. PMID:26593921

  11. Cohort profile: The Berlin Aging Study II (BASE-II).

    PubMed

    Bertram, Lars; Böckenhoff, Anke; Demuth, Ilja; Düzel, Sandra; Eckardt, Rahel; Li, Shu-Chen; Lindenberger, Ulman; Pawelec, Graham; Siedler, Thomas; Wagner, Gert G; Steinhagen-Thiessen, Elisabeth

    2014-06-01

    Similar to other industrialized countries, Germany's population is ageing. Whereas some people enjoy good physical and cognitive health into old age, others suffer from a multitude of age-related disorders and impairments which reduce life expectancy and affect quality of life. To identify and characterize the factors associated with 'healthy' vs. 'unhealthy' ageing, we have launched the Berlin Aging Study II (BASE-II), a multidisciplinary and multi-institutional project that ascertains a large number of ageing-related variables from a wide range of different functional domains. Phenotypic assessments include factors related to geriatrics and internal medicine, immunology, genetics, psychology, sociology and economics. Baseline recruitment of the BASE-II cohort was recently completed and has led to the sampling of 1600 older adults (age range 60-80 years), as well as 600 younger adults (20-35 years) serving as the basic population for in-depth analyses. BASE-II data are linked to the German Socio-Economic Panel Study (SOEP), a long-running panel survey representative of the German population, to estimate sample selectivity. A major goal of BASE-II is to facilitate collaboration with other research groups by freely sharing relevant phenotypic and genotypic data with qualified outside investigators. Published by Oxford University Press on behalf of the International Epidemiological Association © The Author 2013; all rights reserved.

  12. Barriers to evidence-based nursing: a focus group study.

    PubMed

    Hannes, Karin; Vandersmissen, Jo; De Blaeser, Liesbeth; Peeters, Gert; Goedhuys, Jo; Aertgeerts, Bert

    2007-10-01

    This paper reports a study to explore the barriers to evidence-based nursing among Flemish (Belgian) nurses. Barriers obstructing the call for an increase in evidence-based nursing have been explored in many countries, mostly through quantitative study designs. Authors report on lack of time, resources, evidence, authority, support, motivation and resistance to change. Relationships between barriers are seldom presented. We used a grounded theory approach, and five focus groups were organized between September 2004 and April 2005 in Belgium. We used purposeful sampling to recruit 53 nurses working in different settings. A problem tree was developed to establish links between codes that emerged from the data. The majority of the barriers were consistent with previous findings. Flemish (Belgian) nurses added a potential lack of responsibility in the uptake of evidence-based nursing, their 'guest' position in a patient's environment leading to a culture of adaptation, and a future 'two tier' nursing practice, which refers to the different education levels of nurses. The problem tree developed serves as (1) a basic model for other researchers who want to explore barriers within their own healthcare system and (2) a useful tool for orienting change management processes. Despite the fact that the problem tree presented is context-specific for Flanders (Belgium), it gives an opportunity to develop clear objectives and targeted strategies for tackling obstacles to evidence-based nursing.

  13. Social Studies Teachers' Use of Classroom-Based and Web-Based Historical Primary Sources

    ERIC Educational Resources Information Center

    Hicks, David; Doolittle, Peter; Lee, John K.

    2004-01-01

    A limited body of research examines the extent to which social studies teachers are actually utilizing primary sources that are accessible in traditional classroom-based formats versus web-based formats. This paper initiates an exploration of this gap in the literature by reporting on the result of a survey of secondary social studies teachers,…

  14. Comprehension-Based versus Production-Based Grammar Instruction: A Meta-Analysis of Comparative Studies

    ERIC Educational Resources Information Center

    Shintani, Natsuko; Li, Shaofeng; Ellis, Rod

    2013-01-01

    This article reports a meta-analysis of studies that investigated the relative effectiveness of comprehension-based instruction (CBI) and production-based instruction (PBI). The meta-analysis only included studies that featured a direct comparison of CBI and PBI in order to ensure methodological and statistical robustness. A total of 35 research…

  15. Audio-Based versus Text-Based Asynchronous Online Discussion: Two Case Studies

    ERIC Educational Resources Information Center

    Hew, Khe Foon; Cheung, Wing Sum

    2013-01-01

    The main objective of this paper is to examine the use of audio- versus text-based asynchronous online discussions. We report two case studies conducted within the context of semester-long teacher education courses at an Asian Pacific university. Forty-one graduate students participated in Study I. After the online discussions (both audio-based as…

  16. A population-based study of the stratum corneum moisture

    PubMed Central

    de Farias Pires, Thiago; Azambuja, Ana Paula; Horimoto, Andrea Roseli Vançan Russo; Nakamura, Mary Sanae; de Oliveira Alvim, Rafael; Krieger, José Eduardo; Pereira, Alexandre Costa

    2016-01-01

    Background The stratum corneum (SC) has important functions as a bound-water modulator and a primary barrier of the human skin from the external environment. However, no large epidemiological study has quantified the relative importance of different exposures with regard to these functional properties. In this study, we have studied a large sample of individuals from the Brazilian population in order to understand the different relationships between the properties of SC and a number of demographic and self-perceived variables. Methods One thousand three hundred and thirty-nine individuals from a rural Brazilian population, who were participants of a family-based study, were submitted to a cross-sectional examination of the SC moisture by capacitance using the Corneometer® CM820 and investigated regarding environmental exposures, cosmetic use, and other physiological and epidemiological measurements. Self-perception-scaled questions about skin conditions were also applied. Results We found significant associations between SC moisture and sex, age, high sun exposure, and sunscreen use frequency (P<0.025). In specific studied sites, self-reported race and obesity were also found to show significant effects. Dry skin self-perception was also found to be highly correlated with the objective measurement of the skin. Other environmental effects on SC moisture are also reported. PMID:27143945

  17. Evidence-based review of clinical studies on pharmacology (non-anesthetic studies).

    PubMed

    2009-08-01

    We have divided the analysis of pharmacology studies into studies on local anesthetics and studies on all other pharmacologic agents. This division reflects the large number of studies focusing on methods for obtaining effective anesthesia in patients and permits an independent focus on those clinical studies evaluating nonanesthetic drugs. In this section, we review that alternative class of agents, with an emphasis this year on clinical studies evaluating oral analgesics.

  18. Fuzzy-based HAZOP study for process industry.

    PubMed

    Ahn, Junkeon; Chang, Daejun

    2016-11-05

    This study proposed a fuzzy-based HAZOP for analyzing process hazards. Fuzzy theory was used to express uncertain states. This theory was found to be a useful approach to overcome the inherent uncertainty in HAZOP analyses. Fuzzy logic sharply contrasted with classical logic and provided diverse risk values according to its membership degree. Appropriate process parameters and guidewords were selected to describe the frequency and consequence of an accident. Fuzzy modeling calculated risks based on the relationship between the variables of an accident. The modeling was based on the mean expected value, trapezoidal fuzzy number, IF-THEN rules, and the center of gravity method. A cryogenic LNG (liquefied natural gas) testing facility was the objective process for the fuzzy-based and conventional HAZOPs. The most significant index is the frequency to determine risks. The comparison results showed that the fuzzy-based HAZOP provides better sophisticated risks than the conventional HAZOP. The fuzzy risk matrix presents the significance of risks, negligible risks, and necessity of risk reduction.

  19. SVM Method used to Study Gender Differences Based on Microelement

    NASA Astrophysics Data System (ADS)

    Chun, Yang; Yuan, Liu; Jun, Du; Bin, Tang

    [objective] Intelligent Algorithm of SVM is used for studying gender differences based on microelement data, which provide reference For the application of Microelement in healthy people, such as providing technical support for the investigation of cases.[Method] Our Long-term test results on hair microelement of health people were consolidated. Support vector machine (SVM) is used to classified model of male and female based on microelement data. The radical basis function (RBF) is adopted as a kernel function of SVM, and the model adjusts C and σ to build the optimization classifier, [Result] Healthy population of men and women of manganese, cadmium and nickel are quite different, The classified model of Microelement based on SVM can classifies the male and female, the correct classification ratio set to be 81.71% and 66.47% by SVM based on 7 test date and 3 test data selection. [conclusion] The classified model of microelement data based on SVM can classifies male and female.

  20. Study of musculoskeletal risks of the office-based surgeries.

    PubMed

    Hermanson, James E; Choi, Sang D

    2012-01-01

    Due to the cost and time benefits associated with patients and physicians, outpatient surgeries continue to become more and more popular over time. With the increase in the number of office-based surgical procedures, the prevalence of work-related musculoskeletal disorders (WMSDs) associated with office-based surgeries has been reported. The purpose of this pilot study is to ergonomically evaluate the risk of work-related musculoskeletal disorders of physicians/surgeons performing office-based surgery (OBS). Ergonomic assessment tools included Questionnaire, the BodyMap and the Rapid Upper Limb Assessment for measuring potential ergonomic concerns. The findings have shown that the ergonomic issues of greatest concerns were the discomforts in the neck, shoulders, arms/wrists, and back. Some additional comments were provided by the participants regarding the duration of discomfort or clarification on the frequency of their body discomfort. This study suggests that there is a considerable risk of musculoskeletal injuries of physicians/surgeons performing the OBS tasks. By properly using the ergonomic assessment techniques, valuable information on ergonomic OBS workplace design and selection could assist in the early interventions of WMSD prevention.

  1. X-33 Base Region Thermal Protection System Design Study

    NASA Technical Reports Server (NTRS)

    Lycans, Randal W.

    1998-01-01

    The X-33 is an advanced technology demonstrator for validating critical technologies and systems required for an operational Single-Stage-to-Orbit (SSTO) Reusuable Launch Vehicle (RLV). Currently under development by a unique contractor/government team led by Lockheed- Martin Skunk Works (LMSW), and managed by Marshall Space Flight Center (MSFC), the X-33 will be the prototype of the first new launch system developed by the United States since the advent of the space shuttle. This paper documents a design trade study of the X-33 base region thermal protection system (TPS). Two candidate designs were evaluated for thermal performance and weight. The first candidate was a fully reusable metallic TPS using Inconel honeycomb panels insulated with high temperature fibrous insulation, while the second was an ablator/insulator sprayed on the metallic skin of the vehicle. The TPS configurations and insulation thickness requirements were determined for the predicted main engine plume heating environments and base region entry aerothermal environments. In addition to thermal analysis of the design concepts, sensitivity studies were performed to investigate the effect of variations in key parameters of the base TPS analysis.

  2. Laboratory-Based Studies of Eating among Children and Adolescents

    PubMed Central

    Tanofsky-Kraff, Marian; Haynos, Ann F.; Kotler, Lisa A.; Yanovski, Susan Z.; Yanovski, Jack A.

    2008-01-01

    The prevalence of pediatric overweight has increased dramatically over the past three decades, likely due to changes in food intake as well as physical activity. Therefore, information examining eating patterns among children and adolescents is needed to illuminate which aspects of eating behavior require modification to prevent and treat pediatric overweight. Because child self-report and parent-report of children's eating habits are often inconsistent and limited by recall and other biases, laboratory-based studies in which food intake is observed and monitored have increased in number. Such studies offer objective and controlled methods of measuring and describing eating behaviors. However, to our knowledge, no publication exists that consolidates, reviews, and provides critical commentary on the literature to date in pediatric samples. In this paper, we review the literature of studies utilizing laboratory methods to examine eating behavior in samples ranging from birth through adolescence. Our review includes all relevant articles retrieved from the PubMed, Medline and PsychInfo search engines. Specifically, we examine meal-feeding studies conducted during the various developmental stages (infancy, preschool, middle childhood, and adolescence), with a focus on methodology. Included in our review are feeding studies related to dietary regulation, exposure and preference, as well as paradigms examining disordered eating patterns and their relationship to body composition. We have structured this review so that both consistent and inconsistent findings are presented by age group, and innovative methods of assessment are discussed in more detail. Following each section, we summarize findings and draw potential conclusions from the available data. We then discuss clinical implications of the research data and suggest directions for the next generation of studies of feeding behavior in children. PMID:19030122

  3. A study of a tissue equivalent gelatine based tissue substitute

    SciTech Connect

    Spence, J.L.

    1992-11-01

    A study of several tissue substitutes for use as volumetric dosimeters was performed. The tissue substitutes studied included tissue substitutes from previous studies and from ICRU 44. The substitutes were evaluated for an overall match to Reference Man which was used as a basis for this study. The evaluation was based on the electron stopping power, the mass attenuation coefficient, the electron density, and the specific gravity. The tissue substitute chosen also had to be capable of changing from a liquid into a solid form to maintain an even distribution of thermoluminesent dosimetry (TLD) powder and then back to a liquid for recovery of the TLD powder without adversely effecting the TLD powder. The gelatine mixture provided the closest match to the data from Reference Man tissue. The gelatine mixture was put through a series of test to determine it's usefulness as a reliable tissue substitute. The TLD powder was cast in the gelatine mixture and recovered to determine if the TLD powder was adversely effected. The distribution of the TLD powder after being cast into the gelatin mixture was tested in insure an even was maintained.

  4. A study of a tissue equivalent gelatine based tissue substitute

    SciTech Connect

    Spence, J.L.

    1992-11-01

    A study of several tissue substitutes for use as volumetric dosimeters was performed. The tissue substitutes studied included tissue substitutes from previous studies and from ICRU 44. The substitutes were evaluated for an overall match to Reference Man which was used as a basis for this study. The evaluation was based on the electron stopping power, the mass attenuation coefficient, the electron density, and the specific gravity. The tissue substitute chosen also had to be capable of changing from a liquid into a solid form to maintain an even distribution of thermoluminesent dosimetry (TLD) powder and then back to a liquid for recovery of the TLD powder without adversely effecting the TLD powder. The gelatine mixture provided the closest match to the data from Reference Man tissue. The gelatine mixture was put through a series of test to determine it`s usefulness as a reliable tissue substitute. The TLD powder was cast in the gelatine mixture and recovered to determine if the TLD powder was adversely effected. The distribution of the TLD powder after being cast into the gelatin mixture was tested in insure an even was maintained.

  5. Peer assessment in problem-based learning: a qualitative study.

    PubMed

    Papinczak, Tracey; Young, Louise; Groves, Michele

    2007-05-01

    Peer assessment provides a powerful avenue for students to receive feedback on their learning. Although student perceptions of peer assessment have been studied extensively in higher education, little qualitative research has been undertaken with medical students in problem-based learning (PBL) curricula. A qualitative study of students' attitudes to, and perceptions of, peer assessment was undertaken within the framework of a larger study of metacognition with first-year medical students at the University of Queensland. A highly structured format for provision of feedback was utilised in the study design. Many recommendations from the higher education literature on optimal implementation of peer-assessment procedures were put into practice. Results indicated the existence of six main themes: (1) increased responsibility for others, (2) improved learning, (3) lack of relevancy, (4) challenges, (5) discomfort, and (6) effects on the PBL process. Five of these themes have previously been described in the literature. However, the final theme represents a unique, although not unexpected, finding. Students expressed serious concerns about the negative impact of peer assessment on the cooperative, non-judgmental atmosphere of PBL tutorial groups. The practical implications of these findings are considered.

  6. Psoriasis and dyslipidaemia: a population-based study.

    PubMed

    Dreiher, Jacob; Weitzman, Dahlia; Davidovici, Batya; Shapiro, Jonathan; Cohen, Arnon D

    2008-01-01

    Previous reports demonstrated an association between psoriasis and the metabolic syndrome. The aim of this study was to elucidate the association between psoriasis and dyslipidaemia. A cross-sectional study was performed utilizing a population-based database. Psoriasis patients were compared with enrollees without psoriasis regarding the prevalence of dyslipidaemia and lipid levels. Comparison of lipid levels was performed on a "low-risk" subset of subjects without diabetes, hypertension and cardiovascular disease. The study included 10,669 psoriasis patients and 22,996 subjects without psoriasis. The prevalence of dyslipidaemia was significantly higher in psoriasis patients (odds ratio (OR) = 1.48, 95% confidence interval (CI) 1.40-1.55). The association remained significant after controlling for confounders (OR = 1.19, 95% CI 1.12-1.26, p < 0.001). In multivariate analysis of the "low-risk" subset, triglyceride levels were higher in psoriasis patients and high-density lipoprotein cholesterol levels were lower. This study supports previous reports of an association between psoriasis and lipid abnormalities.

  7. Studying inflation with future space-based gravitational wave detectors

    SciTech Connect

    Jinno, Ryusuke; Moroi, Takeo; Takahashi, Tomo E-mail: moroi@phys.s.u-tokyo.ac.jp

    2014-12-01

    Motivated by recent progress in our understanding of the B-mode polarization of cosmic microwave background (CMB), which provides important information about the inflationary gravitational waves (IGWs), we study the possibility to acquire information about the early universe using future space-based gravitational wave (GW) detectors. We perform a detailed statistical analysis to estimate how well we can determine the reheating temperature after inflation as well as the amplitude, the tensor spectral index, and the running of the inflationary gravitational waves. We discuss how the accuracies depend on noise parameters of the detector and the minimum frequency available in the analysis. Implication of such a study on the test of inflation models is also discussed.

  8. Structural Studies of Pterin-Based Inhibitors of Dihydropteroate Synthase

    SciTech Connect

    Hevener, Kirk E.; Yun, Mi-Kyung; Qi, Jianjun; Kerr, Iain D.; Babaoglu, Kerim; Hurdle, Julian G.; Balakrishna, Kanya; White, Stephan W.; Lee, Richard E.

    2010-01-12

    Dihydropteroate synthase (DHPS) is a key enzyme in bacterial folate synthesis and the target of the sulfonamide class of antibacterials. Resistance and toxicities associated with sulfonamides have led to a decrease in their clinical use. Compounds that bind to the pterin binding site of DHPS, as opposed to the p-amino benzoic acid (pABA) binding site targeted by the sulfonamide agents, are anticipated to bypass sulfonamide resistance. To identify such inhibitors and map the pterin binding pocket, we have performed virtual screening, synthetic, and structural studies using Bacillus anthracis DHPS. Several compounds with inhibitory activity have been identified, and crystal structures have been determined that show how the compounds engage the pterin site. The structural studies identify the key binding elements and have been used to generate a structure-activity based pharmacophore map that will facilitate the development of the next generation of DHPS inhibitors which specifically target the pterin site.

  9. Feasibility Study for an Asymmetric B Factory Based on PEP

    SciTech Connect

    Chattapadhyay, A.; Hitlin, D.; Porter, F.; Chin, Y.H.; Dell'Orco, D.; Forest, E.; Furman, M.; Garren, A.A.; Hoyer, E.; Kennedy, K.; Lambertson, G.; Lo, C.C.; Nishimura, H.; Oddone, P.; Ronan, M.; Sessler, A.; Taylor, B.; Taylor, C.; Zisman, M.; Barletta, W.; Allen, M.; Bloom, E.; Burke, D.; Cornacchia, M.; Davies-White, D.; Destaebler, H.; Donald, M.H.; Dorfan, J.; Feldman, G.; Rees, J.; Schsarz, H.; Sullivan, M.; Autin, B.; Tennyson, J.; Barbson, B.; Oide, K.

    1989-10-26

    This report addresses the feasibility of designing and constructing an asymmetric B-factory based on the PEP storage ring at SLAC that can ultimately reach a luminosity of 1 X 10{sup 34} cm{sup -2}s{sup -1}. Such a facility, operating at the {gamma}(4S) resonance, could be used to study mixing, rate decays, and CP violation in the B{bar B} system, and could also study tau and charm physics. The essential accelerator physics, engineering, and technology issues that must be addressed to successfully build this exciting and challenging facility are identified, and possible solutions, or R and D that will reasonable lead to such solutions, are described.

  10. Study on the etching process GaAs-based VCSEL

    NASA Astrophysics Data System (ADS)

    Feng, Yuan; Liu, Guojun; Hao, Yongqin; Yan, Changling; Zhang, Jiabin; Li, Yang; Li, Zaijin

    2016-11-01

    Wet etching process is a key technology in fabrication of VCSEL and their array in order to improve opto-electric characteristics of high-power VCSEL, devices with multi-ring distribution hole VCSEL is fabricated. The H3PO4 etching solution was used in the wet etching progress and etching rate is studied by changing etching solution concentration and etching time. The optimum technological conditions were determined by studying the etching morphology and etching depth of the GaAs-VCSEL. The tested results show that the complete morphology and the appropriate depth can be obtained by using the concentration ratio of 1:1:10, which can meet the requirements of GaAs-based VCSEL micro- structure etching process.

  11. Frame semantics-based study of verbs across medical genres.

    PubMed

    Wandji Tchami, Ornella; L'Homme, Marie-Claude; Grabar, Natalia

    2014-01-01

    The field of medicine gathers actors with different levels of expertise. These actors must interact, although their mutual understanding is not always completely successful. We propose to study corpora (with high and low levels of expertise) in order to observe their specificities. More specifically, we perform a contrastive analysis of verbs, and of the syntactic and semantic features of their participants, based on the Frame Semantics framework and the methodology implemented in FrameNet. In order to achieve this, we use an existing medical terminology to automatically annotate the semantics classes of participants of verbs, which we assume are indicative of semantics roles. Our results indicate that verbs show similar or very close semantics in some contexts, while in other contexts they behave differently. These results are important for studying the understanding of medical information by patients and for improving the communication between patients and medical doctors.

  12. Plasma-based studies on 4th generation light sources

    NASA Astrophysics Data System (ADS)

    Lee, R. W.; Baldis, H. A.; Cauble, R. C.; Landen, O. L.; Wark, J. S.; Ng, A.; Rose, S. J.; Lewis, C.; Riley, D.; Gauthier, J.-C.; Audebert, P.

    2001-08-01

    The construction of a short pulse tunable x-ray laser source will be a watershed for plasma-based and warm dense matter research. The areas we will discuss below can be separated broadly into warm dense matter (WDM) research, laser probing of near solid density plasmas, and laser-plasma spectroscopy of ions in plasmas. The area of WDM refers to that part of the density-temperature phase space where the standard theories of condensed matter physics and/or plasma statistical physics are invalid. Warm dense matter, therefore, defines a region between solids and plasmas, a regime that is found in planetary interiors, cool dense stars, and in every plasma device where one starts from a solid, e.g., laser-solid matter produced plasma as well as all inertial fusion schemes. The study of dense plasmas has been severely hampered by the fact that laser-based methods have been unavailable. The single most useful diagnostic of local plasma conditions, e.g., the temperature (Te), the density (ne), and the ionization (Z), has been Thomson scattering. However, due to the fact that visible light will not propagate at electron densities, ne⩾1022cm-3 implies dense plasmas can not be probed. The 4th generation sources, LCLS and Tesla will remove these restrictions. Laser-based plasma spectroscopic techniques have been used with great success to determine the line shapes of atomic transitions in plasmas, study the population kinetics of atomic systems embedded in plasmas, and look at redistribution of radiation. However, the possibilities end for plasmas with ne⩾1022 since light propagation through the medium is severely altered by the plasma. The entire field of high Z plasma kinetics from laser produced plasma will then be available to study with the tunable source.

  13. Plasma-Based Studies on 4th Generation Light Sources

    SciTech Connect

    Lee, R W; Baldis, H A; Cauble, R C; Landen, O L; Wark, J S; Ng, A; Rose, S J; Lewis, C; Riley, D; Gauthier, J-C; Audebert, P

    2000-11-28

    The construction of a short pulse tunable x-ray laser source will be a watershed for plasma-based and warm dense matter research. The areas we will discuss below can be separated broadly into warn dense matter (WDM) research, laser probing of near solid density plasmas, and laser-plasma spectroscopy of ions in plasmas. The area of WDM refers to that part of the density-temperature phase space where the standard theories of condensed matter physics and/or plasma statistical physics are invalid. Warm dense matter, therefore, defines a region between solids and plasmas, a regime that is found in planetary interiors, cool dense stars, and in every plasma device where one starts from a solid, e.g., laser-solid matter produced plasma as well as all inertial fusion schemes. The study of dense plasmas has been severely hampered by the fact that laser-based methods have been unavailable. The single most useful diagnostic of local plasma conditions, e.g., the temperature (T{sub e}), the density (n{sub e}), and the ionization (Z), has been Thomson scattering. However, due to the fact that visible light will not propagate at electron densities, n{sub e}, {ge} 10{sup 22} cm{sup -3} implies dense plasmas can not be probed. The 4th generation sources, LCLS and Tesla will remove these restrictions. Laser-based plasma spectroscopic techniques have been used with great success to determine the line shapes of atomic transitions in plasmas, study the population kinetics of atomic systems embedded in plasmas, and look at redistribution of radiation. However. the possibilities end for plasmas with n{sub e} {ge} 10{sup 22} since light propagation through the medium is severely altered by the plasma. The entire field of high Z plasma kinetics from laser produced plasma will then be available to study with the tunable source.

  14. Evidence-based medicine for diabetes educators: a pilot study.

    PubMed

    Meyer, G; Köpke, S; Lenz, M; Kasper, J; Mühlhauser, I

    2007-08-01

    Health-care professionals are increasingly asked to communicate research results to patients and consumers. Diabetes educators play a decisive role in the information process of patients with diabetes. Evidence-based medicine (EBM) is not a regular part of their training in Germany. We performed a pilot study to test whether the inclusion of a short EBM module into the standard graduate programme is feasible and leads to a meaningful increase in knowledge and skills. The study group consisted of 121 diabetes educator trainees. The EBM modules were delivered in 1- to 3-day courses. Increase in knowledge and skills were assessed using a questionnaire covering three main elements: (i) general aspects of an intervention study, (ii) effect size calculation, (iii) general aspects of evidence-based patient information and communicating numbers as patient orientated statements. Two researchers independently rated the assessment sheets. The majority of participants rated the course as important and useful but too short. Knowledge and skills in EBM increased after the course by 2 points out of 13.5 (mean score before course 5 +/- 2 vs. 7 +/- 2; P < 0.001). Inter-rater reliability analysis using Cohen's Kappa coefficients demonstrated substantial to almost perfect agreement for 10 of the 13 items. Our pilot study demonstrates that EBM education for diabetes educator trainees is feasible. However, the increase in knowledge and skills appears not to be clinically relevant. Short EBM courses are unlikely to yield important effects. More intensified course formats are necessary to meet the needs of diabetes educators.

  15. Poly(dimethylsiloxane)-based microdevices for studying plant reproduction.

    PubMed

    Arata, Hideyuki; Higashiyama, Tetsuya

    2014-04-01

    Long-term holding and precise handling of growing plant tissues during in vitro cultivation has been a major hurdle for experimental studies related to plant development and reproduction. In the present review, we introduce two of our newly developed poly(dimethylsiloxane)-based microdevices: a T-shaped microchannel device for pollen tube chemoattraction and a microcage array for long-term live imaging of ovules. Their design, usage and advantages are described, and future prospects of experimental approaches to plant reproduction using such microdevices are discussed.

  16. Pentazole-Based Energetic Ionic Liquids: A Computational Study (Postprint)

    DTIC Science & Technology

    2007-01-09

    Postprint) 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Ian S.O. Pimienta , Sherrie Elzey, Mark S. Gordon (Iowa State University...A Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. 239.18 Pentazole-Based Energetic Ionic Liquids: A Computational Study Ian S. O. Pimienta ...2007 Pimienta et al. fully optimized with second-order Møller-Plesset perturbation theory (MP2),32,33 using the restricted Hartree-Fock (RHF)34

  17. Feasibility study of a microprocessor based oculometer system

    NASA Technical Reports Server (NTRS)

    Varanasi, M. R.

    1981-01-01

    The elimination of redundancy in data to maximize processing speed and minimize storage requirements were objectives in a feasibility study of a microprocessor based oculometer system that would be portable in size and flexible in use. The appropriate architectural design of the signal processor, improved optics, and the reduction of size, weight, and power to the system were investigated. A flow chart is presented showing the strategy of the design. The simulation for developing microroutines for the high speed algorithmic processor subsystem is discussed as well as the Karhunen-Loeve transform technique for data compression.

  18. DENSITY-FUNCTIONAL STUDY OF Zr-BASED ACTINIDE ALLOYS

    SciTech Connect

    Landa, A; Soderlind, P; Turchi, P; Vitos, L; Ruban, A

    2008-06-26

    Density-functional formalism is applied to study the phase equilibria in the U-Zr system. The obtained ground-state properties of the {gamma} (bcc) and {delta} (C32) phases are in good agreement with experimental data. The decomposition curve for the {gamma}-based U-Zr solutions is calculated. We argue that stabilization of the {delta}-UZr{sub 2} phase relative to the {alpha}-Zr (hcp) structure is due to an increase of the Zr d-band occupancy that occurs when U is alloyed with Zr.

  19. Ab-initio study of napthelene based conducting polymer

    SciTech Connect

    Ruhela, Ankur; Kanchan, Reena; Srivastava, Anurag; Sinha, O. P.

    2014-04-24

    In this paper, we have identified structural and electronic properties of conducting polymers by using DFT based ATK-VNL ab-initio tool. Naphthalene derivative structures were stabilized by varying the bond length between two atoms of the molecule C-N and C-C. We have also studied the molecular energy spectrum of naphthalene derivatives and found the HOMOLUMO for the same. A comparison of structural and electronic properties of naphthalene derivatives by attaching the functional group of amine, have been performed and found that they show good semi conducting properties.

  20. Geothermal studies at Kirtland Air Force Base, Albuquerque, New Mexico

    SciTech Connect

    Riddle, L.; Grant, B.

    1981-05-01

    Due to an effort by government installations to discontinue use of natural gas, alternative energy sources are being investigated at Kirtland Air Force Base, Albuquerque, New Mexico. New Mexico has geologic characteristics favorable for geothermal energy utilization. Local heat flow and geochemical studies indicate a normal subsurface temperature regime. The alluvial deposits, however, extend to great depths where hot fluids, heated by the normal geothermal gradient, could be encountered. Two potential models for tapping geothermal energy are presented: the basin model and the fault model.

  1. Data base dictionary for the Oak Ridge Reservation Hydrology and Geology Study Groundwater Data Base

    SciTech Connect

    Thompson, B.K.

    1993-04-01

    The Oak Ridge Reservation Hydrology and Geology Study (ORRHAGS) Groundwater Data Base has been compiled to consolidate groundwater data from the three US Department of Energy facilities located on the Oak Ridge Reservation: the Oak Ridge K-25 Site, the Oak Ridge National Laboratory, and the Oak Ridge Y-12 Plant. Each of these facilities maintains its own groundwater and well construction data bases. Data were extracted from the existing data bases, converted to a consistent format, and integrated into the ORRHAGS Groundwater Data Base structures. This data base dictionary describes the data contained in the ORRHAGS Groundwater Data Base and contains information on data base structure, conventions, contents, and use.

  2. Plant-based antimicrobial studies--methods and approaches to study the interaction between natural products.

    PubMed

    van Vuuren, Sandy; Viljoen, Alvaro

    2011-07-01

    The therapeutic value of synergistic interactions has been known since antiquity, and many different cultural healing systems still rely on this principle in the belief that combination therapy may enhance efficacy. This paper intends to provide an overview, from an antimicrobial perspective, on the research undertaken and interactive principles involved in pharmacognosy studies. Methods used to determine antimicrobial interactions include basic combination studies, the sum of the fractional inhibitory concentration index (ΣFIC), isobole interpretations, and death kinetic (time-kill) assays. The various interactions are discussed with reference to molecules, different plant parts or fractions, different plant species, and combinations with nonbotanical antimicrobial agents. It is recommended for future development in the field of phytosynergy that consideration should be given to the selection criteria for the two inhibitors. A more conservative approach should be adopted when classifying synergy. When examining interactions in plant-based studies, antagonistic interactions should not be ignored. Combinations involving more than two test samples should be examined where applicable, and very importantly, the mechanism of action of synergistic interactions should be given precedence. It is encouraging to observe the upsurge in papers exploring the complex interactions of medicinal plants, and undoubtedly this will become increasingly important in our continued quest to understand the mechanism of action of phytotherapy. The scientific validation of efficacious antimicrobial combinations could lead to patentable entities making research in the field of phytosynergy not only academically rewarding but also commercially relevant.

  3. Study of acid-base equilibria of fleroxacin.

    PubMed

    Popović, G; Milovanović, L; Kapetanović, V

    1998-12-01

    The acid-base equilibria of fleroxacin were studied by means of potentiometry and spectrophotometry. It was established that fleroxacin undergoes a complex acid-base equilibrium due to its zwitterionic nature and two proton-binding sites of similar acidity. The stoichiometric equilibrium constants were determined at 25 degrees C and constant ionic strength 0.1 M (NaCl). The acidity constants pK1 = 5.59 +/- 0.01 and pK2 = 8.08 +/- 0.04 were found by potentiometry, and pK1 = 5.61 +/- 0.03 and pK2 = 8.11 +/- 0.06 by spectrophotometry. The distribution diagram of the corresponding ionic species is given.

  4. Studies of oceanic tectonics based on GEOS-3 satellite altimetry

    NASA Technical Reports Server (NTRS)

    Poehls, K. A.; Kaula, W. M.; Schubert, G.; Sandwell, D.

    1979-01-01

    Using statistical analysis, geoidal admittance (the relationship between the ocean geoid and seafloor topography) obtained from GEOS-3 altimetry was compared to various model admittances. Analysis of several altimetry tracks in the Pacific Ocean demonstrated a low coherence between altimetry and seafloor topography except where the track crosses active or recent tectonic features. However, global statistical studies using the much larger data base of all available gravimetry showed a positive correlation of oceanic gravity with topography. The oceanic lithosphere was modeled by simultaneously inverting surface wave dispersion, topography, and gravity data. Efforts to incorporate geoid data into the inversion showed that the base of the subchannel can be better resolved with geoid rather than gravity data. Thermomechanical models of seafloor spreading taking into account differing plate velocities, heat source distributions, and rock rheologies were discussed.

  5. Redefining delusion based on studies of subjective paranormal ideation.

    PubMed

    Houran, James; Lange, Rense

    2004-04-01

    The DSM-IV definition of delusion is argued to be unsatisfactory because it does not explain the mechanism for delusion formation and maintenance, it implies that such beliefs are necessarily dysfunctional (pathological), it underestimates the social component to some delusions, and it is inconsistent with research indicating that delusions can be modified through techniques such as contradiction, confrontation, and cognitive-behavioral therapy. However, a well-replicated mathematical model of magical/delusional thinking based on a study of paranormal beliefs and experiences is consistent with the hypothesis that attributional processes play a central role in delusion formation and maintenance. The model suggests attributional processes serve the adaptive function of reducing fear associated with ambiguous stimuli and delusional thinking is on a continuum with nonpathological forms. Based on this collective research an amendment to the definition of delusion is proposed and its clinical implications are addressed.

  6. Natural oils and waxes: studies on stick bases.

    PubMed

    Budai, Lívia; Antal, István; Klebovich, Imre; Budai, Marianna

    2012-01-01

    The objective of the present article was to examine the role of origin and quantity of selected natural oils and waxes in the determination of the thermal properties and hardness of stick bases. The natural oils and waxes selected for the study were sunflower, castor, jojoba, and coconut oils. The selected waxes were yellow beeswax, candelilla wax, and carnauba wax. The hardness of the formulations is a critical parameter from the aspect of their application. Hardness was characterized by the measurement of compression strength along with the softening point, the drop point, and differential scanning calorimetry (DSC). It can be concluded that coconut oil, jojoba oil, and carnauba wax have the greatest influence on the thermal parameters of stick bases.

  7. Cutoff Designs for Community-Based Intervention Studies

    PubMed Central

    Pennell, Michael L.; Hade, Erinn M.; Murray, David M.; Rhoda, Dale A.

    2011-01-01

    Summary Public health interventions are often designed to target communities defined either geographically (e.g., cities, counties) or socially (e.g., schools or workplaces). The group randomized trial (GRT) is regarded as the gold standard for evaluating these interventions. However, community leaders may object to randomization as some groups may be denied a potentially beneficial intervention. Under a regression discontinuity design (RDD), individuals may be assigned to treatment based on the levels of a pretest measure, thereby allowing those most in need of the treatment to receive it. In this article, we consider analysis, power, and sample size issues in applying the RDD and related cutoff designs in community-based intervention studies. We examine the power of these designs as a function of intraclass correlation, number of groups, and number of members per group and compare results to the traditional GRT. PMID:21500240

  8. Experimental study of photo counting imaging based on APD

    NASA Astrophysics Data System (ADS)

    Qu, Huiming; Li, Yuan-yuan; Cao, Dan; Zheng, Qi; Ji, Zhong-Jie; Chen, Qian

    2012-10-01

    Photo counting imaging is a promising imaging method for very low-level-light condition and super high-speed imaging. An experimental setup with Geiger mode silicon avalanche photodiode single-photon counter was established in this study. This experimental setup achieved photon counting imaging through serial two-dimensional scanning mode of single APD. It extracts the extremely weak signal from the noise by scanning image, and then reconstructs the photon distribution image. The feasibility of the experiment platform was verified with many experiments. The resolution bar was scanned and imaged in different lighting condition. A Lena image was also scanned and imaged among several illumination conditions. The resolution ability and imaging quality are evaluated in different illumination surroundings. The imaging limited condition was concluded based on existing APD sensor. The experimental result indicates that the imaging based Geiger mode APD is an excellent candidate for very low level light imaging.

  9. A simulation based case study for control of DSTATCOM.

    PubMed

    Kumar, Pradeep; Kumar, Niranjan; Akella, A K

    2014-05-01

    This paper presents a distribution static compensator (DSTATCOM) for power quality improvements in terms of harmonics and power factor correction in a three-phase four-wire distribution system. The DSTATCOM is implemented with PWM current controlled six-leg voltage source converter (VSC) and the switching patterns are generated through a novel synchronous reference frame controller (SRFC). The insulated gate bipolar transistor (IGBT) based VSC is supported by a capacitor and is controlled for the required compensation of the load current. The DSTATCOM is connected to the power system feeding nonlinear loads. Nonlinear loads include either current-source type or voltage-source type. Harmonic spectrum of the source current is compared in between without DSTATCOM and with DSTATCOM by considering both types of nonlinear loads. The SRFC based DSTATCOM system is validated through extensive simulation for diode-rectifier and unbalanced R-L loads with a case study.

  10. Saccharomyces cerevisiae-based system for studying clustered DNA damages

    SciTech Connect

    Moscariello, M.M.; Sutherland, B.

    2010-08-01

    DNA-damaging agents can induce clustered lesions or multiply damaged sites (MDSs) on the same or opposing DNA strands. In the latter, attempts to repair MDS can generate closely opposed single-strand break intermediates that may convert non-lethal or mutagenic base damage into double-strand breaks (DSBs). We constructed a diploid S. cerevisiae yeast strain with a chromosomal context targeted by integrative DNA fragments carrying different damages to determine whether closely opposed base damages are converted to DSBs following the outcomes of the homologous recombination repair pathway. As a model of MDS, we studied clustered uracil DNA damages with a known location and a defined distance separating the lesions. The system we describe might well be extended to assessing the repair of MDSs with different compositions, and to most of the complex DNA lesions induced by physical and chemical agents.

  11. Population-based study of lymphoma in Germany: rationale, study design and first results.

    PubMed

    Becker, Nikolaus; Deeg, Evelin; Nieters, Alexandra

    2004-07-01

    A multi-centre, population-based case-control study of lymphoma among adults was conducted in Germany from 1999-2003. The study comprised 700 incident cases (Hodgkin lymphomas and non Hodgkin's lymphoma, NHL) in the age range 18-80 years and 700 age-, sex- and area-matched controls obtained from population registries. Diagnosis was based on the REAL/WHO classification. Information on demographic characteristics, lifestyle, medical history and occupation was obtained by in-person interviews. Each participant was asked for a 24 ml blood sample. First results are focused on basic demographic characteristics, contact to animals, childhood diseases and vaccinations. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using conditional logistic regression. The ORs for lymphoma were decreased for exposure to sheep and goats (OR = 0.7; 95% CI = 0.5-0.9), for rabbits and hare (OR = 0.7; 95% CI = 0.5-0.9), measles infection (OR = 0.6; 95% CI = 0.5-0.9), Bordetella pertussis infection (OR = 0.7; 95% CI = 0.6-0.95), and tetanus vaccination (OR = 0.5; 95% CI = 0.3-0.9). Increased risk of lymphoma was associated with exposure to cattle (OR = 1.3; 95% CI = 1.03-1.7) and immunization for tuberculosis (OR = 1.5; 95% CI = 0.997-2.4). The results of this study are partly consistent with the hygiene hypothesis. The inconsistencies of some of the findings with an explanation by the Th1/Th2 paradigm, however, warrant further research and may indicate that broader explanatory concepts are needed.

  12. Feature-based MRI data fusion for cardiac arrhythmia studies.

    PubMed

    Magtibay, Karl; Beheshti, Mohammadali; Foomany, Farbod Hosseyndoust; Massé, Stéphane; Lai, Patrick F H; Zamiri, Nima; Asta, John; Nanthakumar, Kumaraswamy; Jaffray, David; Krishnan, Sridhar; Umapathy, Karthikeyan

    2016-05-01

    Current practices in studying cardiac arrhythmias primarily use electrical or optical surface recordings of a heart, spatially limited transmural recordings, and mathematical models. However, given that such arrhythmias occur on a 3D myocardial tissue, information obtained from such practices lack in dimension, completeness, and are sometimes prone to oversimplification. The combination of complementary Magnetic-Resonance Imaging (MRI)-based techniques such as Current Density Imaging (CDI) and Diffusion Tensor Imaging (DTI) could provide more depth to current practices in assessing the cardiac arrhythmia dynamics in entire cross sections of myocardium. In this work, we present an approach utilizing feature-based data fusion methods to demonstrate that complimentary information obtained from electrical current distribution and structural properties within a heart could be quantified and enhanced. Twelve (12) pairs of CDI and DTI image data sets were gathered from porcine hearts perfused through a Langendorff setup. Images were fused together using feature-based data fusion techniques such as Joint Independent Component Analysis (jICA), Canonical Correlation Analysis (CCA), and their combination (CCA+jICA). The results suggest that the complimentary information of cardiac states from CDI and DTI are enhanced and are better classified with the use of data fusion methods. For each data set, an increase in mean correlations of fused images were observed with 38% increase from CCA+jICA compared to the original images while mean mutual information of the fused images from jICA and CCA+jICA increased by approximately three-fold. We conclude that MRI-based techniques present potential viable tools in furthering studies for cardiac arrhythmias especially Ventricular Fibrillation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Predicting productivity based on EQ-5D: an explorative study.

    PubMed

    Krol, Marieke; Stolk, Elly; Brouwer, Werner

    2014-06-01

    Productivity costs are often ignored in economic evaluations. In order to facilitate productivity cost inclusion, it has been suggested to estimate productivity costs indirectly using quality of life data. This study aimed to derive and validate an algorithm for predicting productivity losses on the basis of quality-of-life data using the EQ-5D-3L. A large representative sample of the Dutch general public (n = 1,100) was asked in a web-based questionnaire to state their expected level of productivity in terms of absenteeism and presenteeism for multiple EQ-5D health states. Based on these data, two generalized estimating equations (GEE) models were constructed: (1) a model predicting levels of absenteeism and (2) a model predicting presenteeism. The models were validated by comparing model predictions with conventionally measured productivity within a group of low back pain patients. Predicted absenteeism levels based on EQ-5D health state closely resembled conventionally measured absenteeism levels. Productivity losses related to presenteeism seemed somewhat overestimated by our prediction model. Measured and predicted productivity were moderately but highly significantly correlated. Overall, it appears possible to make reasonable productivity predictions based on EQ-5D data. Further exploration and validation of prediction algorithms remains necessary, however, especially for presenteeism.

  14. Clinical TVA-based studies: a general review.

    PubMed

    Habekost, Thomas

    2015-01-01

    In combination with whole report and partial report tasks, the theory of visual attention (TVA) can be used to estimate individual differences in five basic attentional parameters: the visual processing speed, the storage capacity of visual short-term memory, the perceptual threshold, the efficiency of top-down selectivity, and the spatial bias of attentional weighting. TVA-based assessment has been used in about 30 studies to investigate attentional deficits in a range of neurological and psychiatric conditions: (a) neglect and simultanagnosia, (b) reading disturbances, (c) aging and neurodegenerative diseases, and most recently (d) neurodevelopmental disorders. The article introduces TVA based assessment, discusses its methodology and psychometric properties, and reviews the progress made in each of the four research fields. The empirical results demonstrate the general usefulness of TVA-based assessment for many types of clinical neuropsychological research. The method's most important qualities are cognitive specificity and theoretical grounding, but it is also characterized by good reliability and sensitivity to minor deficits. The review concludes by pointing to promising new areas for clinical TVA-based research.

  15. Clinical TVA-based studies: a general review

    PubMed Central

    Habekost, Thomas

    2015-01-01

    In combination with whole report and partial report tasks, the theory of visual attention (TVA) can be used to estimate individual differences in five basic attentional parameters: the visual processing speed, the storage capacity of visual short-term memory, the perceptual threshold, the efficiency of top–down selectivity, and the spatial bias of attentional weighting. TVA-based assessment has been used in about 30 studies to investigate attentional deficits in a range of neurological and psychiatric conditions: (a) neglect and simultanagnosia, (b) reading disturbances, (c) aging and neurodegenerative diseases, and most recently (d) neurodevelopmental disorders. The article introduces TVA based assessment, discusses its methodology and psychometric properties, and reviews the progress made in each of the four research fields. The empirical results demonstrate the general usefulness of TVA-based assessment for many types of clinical neuropsychological research. The method’s most important qualities are cognitive specificity and theoretical grounding, but it is also characterized by good reliability and sensitivity to minor deficits. The review concludes by pointing to promising new areas for clinical TVA-based research. PMID:25852607

  16. Study on Cloud Security Based on Trust Spanning Tree Protocol

    NASA Astrophysics Data System (ADS)

    Lai, Yingxu; Liu, Zenghui; Pan, Qiuyue; Liu, Jing

    2015-09-01

    Attacks executed on Spanning Tree Protocol (STP) expose the weakness of link layer protocols and put the higher layers in jeopardy. Although the problems have been studied for many years and various solutions have been proposed, many security issues remain. To enhance the security and credibility of layer-2 network, we propose a trust-based spanning tree protocol aiming at achieving a higher credibility of LAN switch with a simple and lightweight authentication mechanism. If correctly implemented in each trusted switch, the authentication of trust-based STP can guarantee the credibility of topology information that is announced to other switch in the LAN. To verify the enforcement of the trusted protocol, we present a new trust evaluation method of the STP using a specification-based state model. We implement a prototype of trust-based STP to investigate its practicality. Experiment shows that the trusted protocol can achieve security goals and effectively avoid STP attacks with a lower computation overhead and good convergence performance.

  17. A community-based study of asthenopia in computer operators

    PubMed Central

    Choudhary, Sushilkumar; Doshi, Vikas G

    2008-01-01

    Context: There is growing body of evidence that use of computers can adversely affect the visual health. Considering the rising number of computer users in India, computer-related asthenopia might take an epidemic form. In view of that, this study was undertaken to find out the magnitude of asthenopia in computer operators and its relationship with various personal and workplace factors. Aims: To study the prevalence of asthenopia among computer operators and its association with various epidemiological factors. Settings and Design: Community-based cross-sectional study of 419 subjects who work on computer for varying period of time. Materials and Methods: Four hundred forty computer operators working in different institutes were selected randomly. Twenty-one did not participate in the study, making the nonresponse rate 4.8%. Rest of the subjects (n = 419) were asked to fill a pre-tested questionnaire, after obtaining their verbal consent. Other relevant information was obtained by personal interview and inspection of workstation. Statistical Analysis Used: Simple proportions and Chi-square test. Results: Among the 419 subjects studied, 194 (46.3%) suffered from asthenopia during or after work on computer. Marginally higher proportion of asthenopia was noted in females compared to males. Occurrence of asthenopia was significantly associated with age of starting use of computer, presence of refractive error, viewing distance, level of top of the computer screen with respect to eyes, use of antiglare screen and adjustment of contrast and brightness of monitor screen. Conclusions: Prevalence of asthenopia was noted to be quite high among computer operators, particularly in those who started its use at an early age. Individual as well as work-related factors were found to be predictive of asthenopia. PMID:18158404

  18. A Realistic Seizure Prediction Study Based on Multiclass SVM.

    PubMed

    Direito, Bruno; Teixeira, César A; Sales, Francisco; Castelo-Branco, Miguel; Dourado, António

    2017-05-01

    A patient-specific algorithm, for epileptic seizure prediction, based on multiclass support-vector machines (SVM) and using multi-channel high-dimensional feature sets, is presented. The feature sets, combined with multiclass classification and post-processing schemes aim at the generation of alarms and reduced influence of false positives. This study considers 216 patients from the European Epilepsy Database, and includes 185 patients with scalp EEG recordings and 31 with intracranial data. The strategy was tested over a total of 16,729.80[Formula: see text]h of inter-ictal data, including 1206 seizures. We found an overall sensitivity of 38.47% and a false positive rate per hour of 0.20. The performance of the method achieved statistical significance in 24 patients (11% of the patients). Despite the encouraging results previously reported in specific datasets, the prospective demonstration on long-term EEG recording has been limited. Our study presents a prospective analysis of a large heterogeneous, multicentric dataset. The statistical framework based on conservative assumptions, reflects a realistic approach compared to constrained datasets, and/or in-sample evaluations. The improvement of these results, with the definition of an appropriate set of features able to improve the distinction between the pre-ictal and nonpre-ictal states, hence minimizing the effect of confounding variables, remains a key aspect.

  19. Association of sialolithiasis with cholelithiasis: A population-based study.

    PubMed

    Hung, Shih-Han; Lin, Herng-Ching; Su, Chin-Hui; Chung, Shiu-Dong

    2016-04-01

    The purpose of this study was to evaluate the association between cholelithiasis and developing sialolithiasis using a population-based coverage database. The data for this study were sourced from the Taiwan Longitudinal Health Insurance Database. We included 745 subjects with sialolithiasis as cases and 3725 sex-matched and age-matched subjects without sialolithiasis as controls. Chi-square test revealed a significant difference in the prevalence of prior cholelithiasis between the cases and controls (8.6% vs 4.1%; p < .001). Furthermore, conditional logistic regression analysis indicated that the odds ratio (OR) of prior cholelithiasis for the cases was 2.19 (95% confidence interval [CI] = 1.62-2.98) when compared with the controls after adjusting for monthly income, geographic location, urbanization level, and tobacco use disorder. The adjusted OR of prior cholelithiasis for cases was 2.20 (95% CI = 1.46-3.33) and 2.15 (95% CI = 1.38-3.42) than controls for men and women, respectively. This study demonstrates an association between sialolithiasis and cholelithiasis. © 2015 Wiley Periodicals, Inc.

  20. Synthesis, base pairing and structure studies of geranylated RNA

    PubMed Central

    Wang, Rui; Vangaveti, Sweta; Ranganathan, Srivathsan V.; Basanta-Sanchez, Maria; Haruehanroengra, Phensinee; Chen, Alan; Sheng, Jia

    2016-01-01

    Natural RNAs utilize extensive chemical modifications to diversify their structures and functions. 2-Thiouridine geranylation is a special hydrophobic tRNA modification that has been discovered very recently in several bacteria, such as Escherichia coli, Enterobacter aerogenes, Pseudomonas aeruginosa and Salmonella Typhimurium. The geranylated residues are located in the first anticodon position of tRNAs specific for lysine, glutamine and glutamic acid. This big hydrophobic terpene functional group affects the codon recognition patterns and reduces frameshifting errors during translation. We aimed to systematically study the structure, function and biosynthesis mechanism of this geranylation pathway, as well as answer the question of why nature uses such a hydrophobic modification in hydrophilic RNA systems. Recently, we have synthesized the deoxy-analog of S-geranyluridine and showed the geranylated T-G pair is much stronger than the geranylated T-A pair and other mismatched pairs in the B-form DNA duplex context, which is consistent with the observation that the geranylated tRNAGluUUC recognizes GAG more efficiently than GAA. In this manuscript we report the synthesis and base pairing specificity studies of geranylated RNA oligos. We also report extensive molecular simulation studies to explore the structural features of the geranyl group in the context of A-form RNA and its effect on codon–anticodon interaction during ribosome binding. PMID:27307604

  1. Potential drug interactions with statins: Estonian register-based study

    PubMed Central

    Volmer, Daisy; Hartikainen, Sirpa; Zharkovsky, Alexander

    2015-01-01

    In Estonia, HMG-CoA reductase inhibitors are widely used to modify lipid levels but there are no current data on additional medicines prescribed alongside the statins. The aim of this study was to identify the frequency of potential clinically relevant interactions at a national level among an outpatient population treated with statins between January and June 2008, based on the prescription database of the Estonian Health Insurance Fund. This retrospective prevalence study included 203,646 outpatients aged 50 years or older, of whom 29,367 received statin therapy. The study analysed individuals who had used at least one prescription medicine for a minimum of 7 days concomitantly with statins. Potential drug interactions were analysed using Epocrates online, Stockley’s Drug Interactions, and the drug interaction database developed in Estonia. Statins metabolised by the CYP3A4 isoenzyme were prescribed to 64% of all statin users. Medicines known to have potentially clinically significant interactions with statins were prescribed to 4.6% of patients. The drugs prescribed concomitantly most often with simvastatin were warfarin (5.7%) and amiodarone (3.9%), whereas digoxin (1.2%) and ethinylestradiol (2%) were prescribed with atorvastatin. Potential interactions were not detected in the treatment regimens of rosuvastatin, pravastatin, and fluvastatin users. PMID:28352703

  2. Ground based studies of thermocapillary flows in levitated drops

    NASA Technical Reports Server (NTRS)

    Sadhal, Satwindar Singh; Trinh, Eugene H.

    1994-01-01

    Analytical studies along with ground-based experiments are presently being carried out in connection with thermocapillary phenomena associated with drops and bubbles in a containerless environment. The effort here focuses on the thermal and the fluid phenomena associated with the local heating of acoustically levitated drops, both at 1-g and at low-g. In particular, the Marangoni effect on drops under conditions of local spot-heating and other types of heating are being studied. With the experiments conducted to date, fairly stable acoustic levitation of drops has been achieved and successful flow visualization by light scattering from smoke particles has been carried out. The results include situations with and without heating. As a preliminary qualitative interpretation of these experimental results, we consider the external flow pattern as a superposition of three discrete circulation cells operating on different spatial scales. The observations of the flow fields also indicate the existence of a steady state torque induced by the streaming flows. The theoretical studies have been concentrated on the analysis of streaming flows in a gaseous medium with the presence of a spherical particle undergoing periodic heating. A matched asymptotic analysis was carried out for small parameters derived from approximations in the high frequency range. The heating frequency being 'in tune' with the acoustic frequency results in a nonzero time-averaged thermal field. This leads to a steady heat flow across the equatorial plane of the sphere.

  3. Ground Based Studies of Thermocapillary Flows in Levitated Drops

    NASA Technical Reports Server (NTRS)

    Sadhal, Satwindar Singh; Trinh, Eugene H.

    1996-01-01

    Ground-based experiments together with analytical studies are presently being conducted for levitated drops. Both acoustic and electrostatic techniques are being employed to achieve levitation of drops in a gaseous environment. The scientific effort is principally on the thermal and the fluid phenomena associated with the local heating of levitated drops, both at 1-g and at low-g. In particular, the thermocapillary flow associated with local spot heating is being studied. Fairly stable acoustic levitation of drops has been achieved with some exceptions when random rotational motion of the drop persists. The flow visualization has been carried out by light scattering from smoke particles for the exterior flow and fluorescent tracer particles in the drop. The results indicate a lack of axial symmetry in the internal flow even though the apparatus and the heating are symmetric. The theoretical studies for the past year have included fundamental analyses of acoustically levitated spherical drops. The flow associated with a particle near the velocity antinode is being investigated by the singular perturbation technique. As a first step towards understanding the effect of the particle displacement from the antinode, the flow field about the node has been calculated for the first time. The effect of the acoustic field on the interior of a liquid drop has also been investigated. The results predict that the internal flow field is very weak.

  4. Economic costs of social phobia: a population-based study.

    PubMed

    Acarturk, C; Smit, Filip; de Graaf, R; van Straten, A; Ten Have, M; Cuijpers, P

    2009-06-01

    Information about the economic costs of social phobia is scant. In this study, we examine the economic costs of social phobia and subthreshold social phobia. Data were derived from the Netherlands Mental Health Survey and Incidence Study (NEMESIS) which is a population-based prospective study (n=4,789). Costs related to health service uptake, patients' out-of-pocket expenses, and costs arising from production losses were calculated for the reference year 2003. The costs for people with social phobia were compared with the costs for people with no mental disorder. The annual per capita total costs of social phobia were euro 11,952 (95% CI=7,891-16,013) which is significantly higher than the total costs for people with no mental disorder, euro 2957 (95% CI=2690-3224). When adjusting for mental and somatic co-morbidity, the costs decreased to euro 6,100 (95% CI=2681-9519), or 136 million euro per year per 1 million inhabitants, which was still significantly higher than the costs for people with no mental disorder. The costs of subthreshold social phobia were also significantly higher than the costs for people without any mental disorder, at euro 4,687 (95% CI=2557-6816). The costs presented here are conservative lower estimates because we only included costs related to mental health services. The economic costs associated with social phobia are substantial, and those of subthreshold social phobia approach those of the full-blown disorder.

  5. A study of trends and techniques for space base electronics

    NASA Technical Reports Server (NTRS)

    Trotter, J. D.; Wade, T. E.; Gassaway, J. D.; Mahmood, Q.

    1978-01-01

    A sputtering system was developed to deposit aluminum and aluminum alloys by the dc sputtering technique. This system is designed for a high level of cleanliness and for monitoring the deposition parameters during film preparation. This system is now ready for studying the deposition and annealing parameters upon double-level metal preparation. A technique recently applied for semiconductor analysis, the finite element method, was studied for use in the computer modeling of two dimensional MOS transistor structures. It was concluded that the method has not been sufficiently well developed for confident use at this time. An algorithm was developed for confident use at this time. An algorithm was developed for implementing a computer study which is based upon the finite difference method. The program which was developed was modified and used to calculate redistribution data for boron and phosphorous which had been predeposited by ion implantation with range and straggle conditions. Data were generated for 111 oriented SOS films with redistribution in N2, dry O2 and steam ambients.

  6. Synthesis, characterization and antimicrobial studies of Schiff base complexes

    NASA Astrophysics Data System (ADS)

    Zafar, Hina; Ahmad, Anis; Khan, Asad U.; Khan, Tahir Ali

    2015-10-01

    The Schiff base complexes, MLCl2 [M = Fe(II), Co(II), Ni(II), Cu(II) and Zn(II)] have been synthesized by the template reaction of respective metal ions with 2-acetylpyrrole and 1,3-diaminopropane in 1:2:1 M ratio. The complexes have been characterized by elemental analyses, ESI - mass, NMR (1H and 13C), IR, XRD, electronic and EPR spectral studies, magnetic susceptibility and molar conductance measurements. These studies show that all the complexes have octahedral arrangement around the metal ions. The molar conductance measurements of all the complexes in DMSO indicate their non-electrolytic nature. The complexes were screened for their antibacterial activity in vitro against Gram-positive (Streptococcus pyogenes) and Gram-negative (Klebsiella pneumoniae) bacteria. Among the metal complexes studied the copper complex [CuLCl2], showed highest antibacterial activity nearly equal to standard drug ciprofloxacin. Other complexes also showed considerable antibacterial activity. The relative order of activity against S. Pyogenes is as Cu(II) > Zn(II) > Co(II) = Fe(II) > Ni(II) and with K. Pneumonia is as Cu(II) > Co(II) > Zn(II) > Fe(II) > Ni(II).

  7. Study of Mare Moscoviense based on orbital NIR hyperspectral data

    NASA Astrophysics Data System (ADS)

    Bhatt, Megha; Wöhler, Christian; Bhardwaj, Anil; Mall, Urs; Grumpe, Arne; Rommel, Daniela

    2016-07-01

    The Moscoviense basin is an important lunar farside impact basin. Previous studies of this region suggest compositional variations across the mare basalts, and significant positive gravity anomaly within the basin [1, 2]. In the highlands immediately west of the mare regions inside the Moscoviense basin, unusual spectral signatures indicating small deposits of orthopyroxene, olivine and spinel have been detected [3]. A detailed study of the Moscoviense basin thus allows for an examination of lunar farside highland materials and mare basalts of varying composition and age, providing insights into the lunar mantle composition and magmatic history. We present a geological study of Mare Moscoviense based on near-infrared high-resolution hyperspectral data obtained by the Moon Mineralogy Mapper (M3) [4] and the near-infrared spectrometer, SIR-2 [5]. An M3 reflectance mosaic of the region has been prepared after applying corrections for thermal emission and topography. Two SIR-2 orbits recorded from 100 km spacecraft altitude have also been used for mineralogical study of the region. Elemental abundance maps of Ti, Ca and Mg as well as a petrologic map have been prepared based on the method described in [6]. Furthermore, we utilized the three different algorithms described in [6, 7, 8] for estimating Fe abundances using the 1-µm and/or 2-µm absorption band parameters. This comparative study aims to identify and map the major morphological and compositional units within the Mare Moscoviense region. References: [1] Gillis et al. (1998) Ph.D. thesis, 248 pp., Rice Univ., Houston, Texas; [2] Kramer et al. (2008) JGR 113, E01002, doi:10.1029/2006JE002860; [3] Pieters et al. (2011) JGR 116, E00G08, doi:10.1029/2010JE003727; [4] Pieters C. M. et al. (2009) Current Science 96, 500-505; [5] Mall, U. et al. (2009) Current Science 96, 506-511; [6] Wöhler C. et al. (2014) Icarus 235, 86-122; [7] Lucey P. G. et al. (2000) JGR 105, 20297-20306; [8] Bhatt M. et al. (2015) Icarus 248

  8. Can remote sensing help citizen-science based phenological studies?

    NASA Astrophysics Data System (ADS)

    Delbart, Nicolas; Elisabeth, Beaubien; Laurent, Kergoat; Thuy, Le Toan

    2017-04-01

    Citizen science networks and remote sensing are both efficient to collect massive data related to phenology. However both differ in their advantages and drawbacks for this purpose. Contrarily to remote sensing, citizen science allows distinguishing species-specific phenological responses to climate variability. On the other hand, large portions of territory of a country like Canada are not covered by citizen science networks, and the time series are often incomplete. The main mode of interaction between both types of data consists in validating the maps showing the ecosystem foliage transition times, such as the green-up date, obtained from remote sensing data with field observations, and in particular those collected by citizen scientists. Thus the citizen science phenology data bring confidence to remote sensing based studies. However, one can merely find studies in which remote sensing is used to improve in any way citizen science based study. Here we present bi-directional interactions between both types of data. We first use phenological data from the PlantWatch citizen science network to show that one remote sensing method green-up date relates to the leaf-out date of woody species but also to the whole plant community phenology at the regional level, including flowering phenology. Second we use a remote sensing time series to constrain the analysis of citizen data to overcome the main drawbacks that is the incompleteness of time series. In particular we analyze the interspecies differences in phenology at the scale of so-called "pheno-regions" delineated using remote sensing green-up maps.

  9. Young adults' trajectories of Ecstasy use: a population based study.

    PubMed

    Smirnov, Andrew; Najman, Jake M; Hayatbakhsh, Reza; Plotnikova, Maria; Wells, Helene; Legosz, Margot; Kemp, Robert

    2013-11-01

    Young adults' Ecstasy use trajectories have important implications for individual and population-level consequences of Ecstasy use, but little relevant research has been conducted. This study prospectively examines Ecstasy trajectories in a population-based sample. Data are from the Natural History Study of Drug Use, a retrospective/prospective cohort study conducted in Australia. Population screening identified a probability sample of Ecstasy users aged 19-23 years. Complete data for 30 months of follow-up, comprising 4 time intervals, were available for 297 participants (88.4% of sample). Trajectories were derived using cluster analysis based on recent Ecstasy use at each interval. Trajectory predictors were examined using a generalized ordered logit model and included Ecstasy dependence (World Mental Health Composite International Diagnostic Instrument), psychological distress (Hospital Anxiety Depression Scale), aggression (Young Adult Self Report) and contextual factors (e.g. attendance at electronic/dance music events). Three Ecstasy trajectories were identified (low, intermediate and high use). At its peak, the high-use trajectory involved 1-2 days Ecstasy use per week. Decreasing frequency of use was observed for intermediate and high-use trajectories from 12 months, independently of market factors. Intermediate and high-use trajectory membership was predicted by past Ecstasy consumption (>70 pills) and attendance at electronic/dance music events. High-use trajectory members were unlikely to have used Ecstasy for more than 3 years and tended to report consistently positive subjective effects at baseline. Given the social context and temporal course of Ecstasy use, Ecstasy trajectories might be better understood in terms of instrumental rather than addictive drug use patterns. © 2013 Elsevier Ltd. All rights reserved.

  10. Incidence of Radiologically Isolated Syndrome: A Population-Based Study.

    PubMed

    Forslin, Y; Granberg, T; Jumah, A Antwan; Shams, S; Aspelin, P; Kristoffersen-Wiberg, M; Martola, J; Fredrikson, S

    2016-06-01

    Incidental MR imaging findings resembling MS in asymptomatic individuals, fulfilling the Okuda criteria, are termed "radiologically isolated syndrome." Those with radiologically isolated syndrome are at high risk of their condition converting to MS. The epidemiology of radiologically isolated syndrome remains largely unknown, and there are no population-based studies, to our knowledge. Our aim was to study the population-based incidence of radiologically isolated syndrome in a high-incidence region for MS and to evaluate the effect on radiologically isolated syndrome incidence when revising the original radiologically isolated syndrome criteria by using the latest radiologic classification for dissemination in space. All 2272 brain MR imaging scans in 1907 persons obtained during 2013 in the Swedish county of Västmanland, with a population of 259,000 inhabitants, were blindly evaluated by a senior radiologist and a senior neuroradiologist. The Okuda criteria for radiologically isolated syndrome were applied by using both the Barkhof and Swanton classifications for dissemination in space. Assessments of clinical data were performed by a radiology resident and a senior neurologist. The cumulative incidence of radiologically isolated syndrome was 2 patients (0.1%), equaling an incidence rate of 0.8 cases per 100,000 person-years, in a region with an incidence rate of MS of 10.2 cases per 100,000 person-years. There was no difference in the radiologically isolated syndrome incidence rate when applying a modified version of the Okuda criteria by using the newer Swanton classification for dissemination in space. Radiologically isolated syndrome is uncommon in a high-incidence region for MS. Adapting the Okuda criteria to use the dissemination in space-Swanton classification may be feasible. Future studies on radiologically isolated syndrome may benefit from a collaborative approach to ensure adequate numbers of participants. © 2016 by American Journal of Neuroradiology.

  11. Metabolic Syndrome among Emirati Adolescents: A School-Based Study

    PubMed Central

    Mehairi, Aaesha E.; Khouri, Aysha A.; Naqbi, Muna M.; Muhairi, Shamma J.; Maskari, Fatima A.; Nagelkerke, Nico; Shah, Syed M.

    2013-01-01

    Objectives Population-based data on metabolic syndrome (MetS) among children is lacking in the United Arab Emirates which has among the highest rates of diabetes in the world. In this study we determined the prevalence of MetS and its correlates in a sample of adolescents. Materials and Methods A cross-sectional school-based study was conducted on 1,018 adolescents (48.4% girls) aged 12–18 years from Al Ain Abu Dhabi Emirates. A self-administered questionnaire was used to assess socio-demographic characteristics, physical activity and dietary habits. Blood pressure, height, weight, waist circumference, fasting glucose, HDL-cholesterol and triglycerides were measured. MetS was defined using the International Diabetes Federation (IDF) criteria. Results The prevalence of metabolic syndrome was 13%. Boys compared to girls were more likely to have MetS (21% vs. 4%, odds ratio [OR]: 6.57, 95%CI: 4.01 to 10.75). The prevalence of MetS increased with increase in body mass index and reached 59 percent in obese boys. After multivariable adjustment boys who were overweight (adjusted OR: 2.72 [1.37 to 5.35]), or obese (AOR: 12.70 [7.31 to 22.05]), or spent two or more than two hours on screen in a day (AOR: 1.65 [1.01 to 2.69) were more likely to have MetS. Girls who were overweight (AOR: 4.23 [1.32 to 13.62]) or obese (AOR: 8.32 [2.73 to 25.32]) were more likely to have MetS. Conclusions The prevalence of MetS is high among UAE boys. Population-based strategies are needed to address the high burden of metabolic syndrome targeted at the identified risk factors. PMID:23418529

  12. Validation study of a Kinect based body imaging system.

    PubMed

    Bragança, Sara; Arezes, Pedro; Carvalho, Miguel; Ashdown, Susan P; Xu, Bugao; Castellucci, Ignacio

    2017-01-01

    Understanding the reliability and precision of the data obtained using three-dimensional body scanners is very important if it is intended to replace the traditional data collection methods. If the collection of anthropometric data with three-dimensional body scanners is a fast and reliable process that produces precise data at a low price, it could be used for numerous applications worldwide. Many studies have addressed data collected by white light and laser based scanners. This study provides a comparative analysis between the anthropometric data collected using a Kinect body imaging system with the data collected using traditional manual methods. Moreover, a comparison is also made between the results obtained in this study and the results of previous studies of different types of body scanners. The Mean Absolute Difference was calculated and all the values were compared to the maximum allowable error defined in ISO 20685. Additionally, an analysis of the significant differences between the two acquisition methods was also applied to a physical mannequin, to understand how the body movement and body stance variation in human participants impacts the results obtained. There are few body measurements that are close to this restricted allowable error. The results were better when the mannequin was measured. Although they were still above the ISO 20685 limit, they were much closer than the results obtained for human participants. The main cause of the differences between the two methods is the time required for the 3D system to acquire the data. The involuntary body sway of human participants is more difficult to control when the time span is too long.

  13. Fetal Growth and Childhood Cancer: A Population-Based Study

    PubMed Central

    Sørensen, Henrik Toft; Grotmol, Tom; Engeland, Anders; Stephansson, Olof; Gissler, Mika; Tretli, Steinar; Troisi, Rebecca

    2013-01-01

    OBJECTIVE: The etiology of childhood cancers is largely unknown. Studies have suggested that birth characteristics may be associated with risk. Our goal was to evaluate the risk of childhood cancers in relation to fetal growth. METHODS: We conducted a case-control study nested within Nordic birth registries. The study included cancer cases diagnosed in Denmark, Finland, Norway, and Sweden among children born from 1967 to 2010 and up to 10 matched controls per case, totaling 17 698 cases and 172 422 controls. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were derived from conditional logistic regression. RESULTS: Risks of all childhood cancers increased with increasing birth weight (Ptrend ≤ .001). Risks of acute lymphoid leukemia and Wilms tumor were elevated when birth weight was >4000 g and of central nervous system tumors when birth weight was >4500 g. Newborns large for gestational age were at increased risk of Wilms tumor (OR: 2.1 [95% CI: 1.2–3.6]) and connective/soft tissue tumors (OR: 2.1 [95% CI: 1.1–4.4]). In contrast, the risk of acute myeloid leukemia was increased among children born small for gestational age (OR: 1.8 [95% CI: 1.1–3.1]). Children diagnosed with central nervous system tumors at <1 year of age had elevated risk with increasing head circumference (Ptrend < .001). Those with head circumference >39 cm had the highest risk (OR: 4.7 [95% CI: 2.5–8.7]). CONCLUSIONS: In this large, Nordic population-based study, increased risks for several childhood tumors were associated with measures of fetal growth, supporting the hypothesis that tumorigenesis manifesting in childhood is initiated in utero. PMID:24167169

  14. Tin Mossbauer Study of Uranium-Based Intermetallic -

    NASA Astrophysics Data System (ADS)

    Yuen, Tan

    The temperature and concentration dependences of the ^{119}Sn Mossbauer spectra, magnetic susceptibility and specific heat have been measured for the uranium based pseudobinary alloys, rm U(Pb_{1-x}Sn_ {x})_3 and rm U(In _{1-x}Sn_{x})_3 , and ternary compound UNiSn. UPb_3 and UIn_3 appear to be an antiferromagnets, whereas USn _3 appears to be very near to the border between magnetic and nonmagnetic behavior. The low temperature ^{119}Sn Mossbauer spectra of rm U(Pb_{1-x}Sn_ {x})_3 for 0.02 <=q x <=q 0.85 and rm U(In_{1-x}Sn_{x})_3 for 0.02 <=q x <=q 0.6 show the existence of a magnetic hyperfine field at the Sn sites. The result for these two systems indicate that the magnetic structures of the Pb-rich and In-rich alloys are incompatible with the magnetic structures previously proposed on the basis of neutron diffraction data for pure UPb_3 and UIn _3. An identical magnetic structure is proposed for both systems, having a magnetic unit cell of (2a,2a,2a) (where a is the lattice constant of the crystal unit cell) and in which the U magnetic moments alternate between the eight possible (+/-1,+/- 1,+/-) directions. The new structure is consistent with both neutron diffraction and Mossbauer results. UNiSn is a half-metallic antiferromagnet. The ^{119}Sn Mossbauer study shows that the annealing procedures influence the microscopic properties of the sample in a profound way. Anomalies in the temperature dependence of the specific heat, low field magnetization and the temperature derivative of the electrical resistivity indicates a magnetic transition at 43 K. However, the ^{119} Sn Mossbauer study suggests that substantial magnetic correlations persist to higher temperatures. In addition, the magnetic structure determined by neutron diffraction study is found to be consistent with the result of Mossbauer study.

  15. Biologically based epidemiological studies of electric power and cancer

    SciTech Connect

    Stevens, R.G.

    1993-12-01

    Use of electricity is a hallmark of the industrialization process, but there has been no suspicion that electricity could increase the risk of cancer. Recently, however, a number of epidemiologic studies have suggested that electromagnetic fields (EMF) may do just that. Although few cancer experiments have been done yet, there are a number of biological effects of EMF reported in the literature that might provide bases for designing cancer experiments and epidemiologic studies. These include effects of EMF on: (a) DNA transcription and translation, (b) calcium balance in cells, and (c) pineal production of melatonin. Alterations in DNA transcription and translation could have pleiotropic effects. Disruption of calcium homeostasis has many implications including oncogene activation, promotional activity via protein kinases and ornithine decarboxylase (ODC), and increasing oxidative stress. Reduction of melatonin suggests a possible increased risk of cancers of hormone-dependent tissues such as breast and prostate. The idea that a cancer-causing agent must either be an initiator or a promoter should be discarded; indeed, the phenomenologic meaning of these two terms has become confused with imputed mechanistic necessity in recent years. Agents that affect division of normal cells or of fully transformed cells can play an important role in clinical cancer development quite apart from initiation or promotion. Epidemiologic studies of EMF and cancer should attempt to take account of other products of electric power (e.g., light at night) or factors associated with occupational EMF exposure (e.g., toxic chemicals) that may increase cancer risk and therefore act as cofactors or confounders. Epidemiology and laboratory studies should act synergistically in determining if there is a problem and identifying mitigation strategies if needed. 84 refs., 3 figs., 1 tab.

  16. "EMMA Study: a Brazilian community-based cohort study of stroke mortality and morbidity".

    PubMed

    Goulart, Alessandra Carvalho

    2016-01-01

    Stroke has a high burden of disability and mortality. The aim here was to evaluate epidemiology, risk factors and prognosis for stroke in the EMMA Study (Study of Stroke Mortality and Morbidity). Prospective community-based cohort carried out in Hospital Universitário, University of São Paulo, 2006-2014. Stroke data based on fatal and non-fatal events were assessed, including sociodemographic data, mortality and predictors, which were evaluated by means of logistic regression and survival analyses. Stroke subtype was better defined in the hospital setting than in the local community. In the hospital phase, around 70% were first events and the ischemic subtype. Among cerebrovascular risk factors, the frequency of alcohol intake was higher in hemorrhagic stroke (HS) than in ischemic stroke (IS) cases (35.4% versus 12.3%, P < 0.001). Low education was associated with higher risk of death, particularly after six months among IS cases (odds ratio, OR, 4.31; 95% confidence interval, CI, 1.34-13.91). The risk of death due to hemorrhagic stroke was greater than for ischemic stroke and reached its maximum 10 days after the event (OR: 3.31; 95% CI: 1.55-7.05). Four-year survival analysis on 665 cases of first stroke (82.6% ischemic and 17.4% hemorrhagic) showed an overall survival rate of 48%. At four years, the highest risks of death were in relation to ischemic stroke and illiteracy (hazard ratio, HR: 1.83; 95% CI: 1.26-2.68) and diabetes (HR: 1.45; 95% CI: 1.07-1.97). Major depression presented worse one-year survival (HR: 4.60; 95% CI: 1.36-15.55). Over the long term, the EMMA database will provide additional information for planning resources destined for the public healthcare system.

  17. Sitewide feasibility study Eielson Air Force Base, Alaska

    SciTech Connect

    Last, G.V.; Lanigan, D.C.; Josephson, G.B.; Bagaasen, L.M.

    1995-09-01

    The Sitewide Feasibility Study (FS) is required under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), the National Contingency Plan (NCP), and the Federal Facility Agreement (FFA) for Eielson Air Force Base (AFB). It is based on findings presented in the Sitewide Remedial Investigation (RI) Report (USAF 1995a), and the Sitewide Baseline Risk Assessment (BLRA) Report (USAF 1995b). Under the FFA, 64 potential source areas were placed in one of six operable units, based on similar contaminant and environmental characteristics, or were included for evaluation under a Source Evaluation Report (SER). The sitewide RI was directed at contamination that was not confined to an operable unit (OU) or SER source area. The objectives of the sitewide RI were to: Provide information about site characteristics to support individual OU RI/FS efforts and the sitewide RI/FS, including site hydrogeology and determination of background soil and groundwater characteristics; identify and characterize contamination that is not confined or attributable to a specific source area through sitewide monitoring of groundwater and surface water; evaluate cumulative risks to human health and the environment from contamination on a sitewide basis; and provide a mechanism for continued cohesive sitewide monitoring.

  18. An electronic study guide for problem-based learning.

    PubMed

    Mooney, G A; Bligh, J G; Leinster, S F; Warenius, H M

    1995-11-01

    This paper describes the development and structure of an Electronic Study Guide for Oncology (LETSGO) for undergraduate medical students. LETSGO is aimed at clinical students learning about cancer. The subject of the guide is breast cancer and learning objectives cover structure and function, behavioural science, public health and epidemiology and professional and personal values. LETSGO is designed to follow the steps used in problem-based learning. The student is encouraged to carry out individual brainstorming around cases with the issues identified acting as the first step in an educational audit loop. Clear definition of prior knowledge is available by way of interactive features, and hyper-text links to core text and diagrams (including microscopic sections) precede definition of both broad aims and objectives for the module and specific objectives for assessment purposes. Core knowledge is available via hyper-text links. Assessment has three components: open ended questions asking for free text responses linking to 'model' answers; extended matching items linking to 'model' answers and providing peer-referenced feedback as a bar-chart distribution, and an educational audit loop referring back to the original issues identified at the beginning of the package in brainstorming. Clear mapping throughout the guide is a major feature and the student's progress is clearly displayed at each stage of the guide. The program provides dynamic access to the student's existing knowledge base and stimulates new learning based on the student's own learning needs.

  19. Study of model based etch bias retarget for OPC

    NASA Astrophysics Data System (ADS)

    Liu, Qingwei; Cheng, Renqiang; Zhang, Liguo

    2010-04-01

    Model based Optical proximity correction is usually used to compensate for the pattern distortion during the microlithography process. Currently, almost all the lithography effects, such as the proximity effects from the limited NA, the 3D mask effects due to the shrinking critical dimension, the photo resist effects, and some other well known physical process, can all be well considered into modeling with the OPC algorithm. However, the micro-lithography is not the final step of the pattern transformation procedure from the mask to the wafer. The etch process is also a very important stage. It is well known that till now, the etch process still can't be well explained by physics theory. As we all know, the final critical dimension is decided by both the lithography and the etch process. If the etch bias, which is the difference between the post development CD and the post etch CD, is a constant value, it will be simple to control the final CD. But unfortunately this is always not the case. For advanced technology nodes with shrinking critical dimension, the etch loading effect is the dominate factor that impacts the final CD control. And some people tried to use the etch-based model to do optical proximity correction, but one drawback is the efficiency of the OPC running will be hurt. In this paper, we will demonstrate our study on the model based etch bias retarget for OPC.

  20. Feasibility study of a soil-based rubberized CLSM.

    PubMed

    Wu, Jason Y; Tsai, Mufan

    2009-02-01

    The development of beneficial uses of recycled scrap tires is always in great demand around the world. The disposal of on-site surplus excavated soil and the production of standard engineering aggregates have also been facing increasing environmental and ecological challenges in congested islands, such as Taiwan. This paper presents an experimental study using recycled crumb rubber and native silty sand to produce a lightweight, soil-based, rubberized controlled low strength material (CLSM) for a bridge approach repair. To assess the technical feasibility of this material, the effects of weight ratios of cement-to-water (C/W) and water-to-solid (W/S), and of rubber content on the engineering properties for different mixtures were investigated. The presented test results include flowability, unit weight, strength, settlement potential, and bearing capacity. Based on the findings, we conclude that a soil-based rubberized CLSM with 40% sand by weight and an optimal design ratio of 0.7 for C/W and 0.35 for W/S can be used for the proposed bridge approach repair. Such a mixture has demonstrated acceptable flowability, strength, and bearing capacity. Its lower unit weight, negligible compressibility, and hydrocollapse potential also help ensure that detrimental settlement is unlikely to occur. The results illustrate a novel scheme of CLSM production, and suggest a beneficial alternative for the reduction of scrap tires as well as conservation of resources and environment.

  1. Instructor Based Training Versus Computer Based Training--A Comparative Study

    ERIC Educational Resources Information Center

    Malmskold, Lennart; Ortengren, Roland; Carlson, Blair E.; Nylen, Per

    2007-01-01

    This article describes two studies conducted to compare assembly performance and learning rate between computer based training and traditional training of skilled assembly operators. The studies were performed with pre-series production parts from a car cockpit and they were integrated as part of the overall training activities during a new…

  2. Insomnia in probable migraine: a population-based study.

    PubMed

    Kim, Jiyoung; Cho, Soo-Jin; Kim, Won-Joo; Yang, Kwang Ik; Yun, Chang-Ho; Chu, Min Kyung

    2016-12-01

    Insomnia is a common complaint among individuals with migraine. The close association between insomnia and migraine has been reported in clinic-based and population-based studies. Probable migraine (PM) is a migrainous headache which fulfills all but one criterion in the migraine diagnostic criteria. However, an association between insomnia and PM has rarely been reported. This study is to investigate the association between insomnia and PM in comparison with migraine using data from the Korean Headache-Sleep Study. The Korean Headache-Sleep Study is a nation-wide cross-sectional survey for all Korean adults aged 19-69 years. The survey was performed via face-to-face interview using a questionnaire on sleep and headache. If an individual's Insomnia Severity Index score was ≥15.5, she/he was diagnosed as having insomnia. Of 2695 participants, the prevalence of migraine, PM and insomnia was 5.3, 14.1 and 3.6 %, respectively. The prevalence of insomnia among subjects with PM was not significantly different compared to those with migraine (8.2 % vs. 9.1 %, p = 0.860). However, insomnia prevalence in subjects with PM was significantly higher than in non-headache controls (8.2 % vs. 1.8 %, p < 0.001). Insomnia Severity Index score was significantly higher in subjects with migraine compared to those with PM (6.8 ± 5.8 vs. 5.5 ± 5.8, p = 0.012). Headache frequency and Headache Impact Test-6 score were significantly higher in subjects with migraine and PM with insomnia compared to those without insomnia. Multivariable linear analyses showed that anxiety, depression, headache frequency and headache intensity were independent variables for contributing the ISI score among subjects with PM. The prevalence of insomnia among subjects with PM was not significantly different compared to those with migraine. Anxiety, depression, headache frequency and headache intensity were related with ISI score in subjects with PM.

  3. Construction Material-Based Methodology for Military Contingency Base Construction: Case Study of Dhaka, Bangladesh

    DTIC Science & Technology

    2016-08-01

    Military Contingency Base Construction Case Study of Dhaka, Bangladesh Co ns tr uc tio n En gi ne er in g R es ea rc h La bo ra to ry...Construction Case Study of Dhaka, Bangladesh Ghassan K. Al-Chaar, George W. Calfas, Michael A. Weiss, Michael K. Valentino, and Patrick J. Guertin...can be replicated in other locations throughout the world. This work then validates the developed methodology with a case study of Dhaka, Bangladesh

  4. Synthesis and study of novel silicon-based unsaturated polymers

    SciTech Connect

    Lin, Jibing

    1995-06-19

    Novel unsaturated polymers have been synthesized and studied as precursors to silicon carbide and third order nonlinear optical materials. X ray structures were obtained. Kinetic and mechanistic studies of the unique thermal isomerization of dimethylenedisilacyclobutane to a carbene were conducted.

  5. A Study on the Efficacy of Project-Based Learning Approach on Social Studies Education: Conceptual Achievement and Academic Motivation

    ERIC Educational Resources Information Center

    Ilter, Ilhan

    2014-01-01

    In this research, an experimental study was carried out in social studies 4th grade students to develop students' conceptual achievement and motivation to succeed academically. The study aims to investigate the effectiveness of project-based learning (PBL) in social studies. A quasi-experimental research design (pre- and posttest) was used in the…

  6. A Study on the Efficacy of Project-Based Learning Approach on Social Studies Education: Conceptual Achievement and Academic Motivation

    ERIC Educational Resources Information Center

    Ilter, Ilhan

    2014-01-01

    In this research, an experimental study was carried out in social studies 4th grade students to develop students' conceptual achievement and motivation to succeed academically. The study aims to investigate the effectiveness of project-based learning (PBL) in social studies. A quasi-experimental research design (pre- and posttest) was used in the…

  7. Study of Flapping Flight Using Discrete Vortex Method Based Simulations

    NASA Astrophysics Data System (ADS)

    Devranjan, S.; Jalikop, Shreyas V.; Sreenivas, K. R.

    2013-12-01

    In recent times, research in the area of flapping flight has attracted renewed interest with an endeavor to use this mechanism in Micro Air vehicles (MAVs). For a sustained and high-endurance flight, having larger payload carrying capacity we need to identify a simple and efficient flapping-kinematics. In this paper, we have used flow visualizations and Discrete Vortex Method (DVM) based simulations for the study of flapping flight. Our results highlight that simple flapping kinematics with down-stroke period (tD) shorter than the upstroke period (tU) would produce a sustained lift. We have identified optimal asymmetry ratio (Ar = tD/tU), for which flapping-wings will produce maximum lift and find that introducing optimal wing flexibility will further enhances the lift.

  8. Predictors of Childhood Anxiety: A Population-Based Cohort Study

    PubMed Central

    2015-01-01

    Background Few studies have explored predictors of early childhood anxiety. Objective To determine the prenatal, postnatal, and early life predictors of childhood anxiety by age 5. Methods Population-based, provincial administrative data (N = 19,316) from Manitoba, Canada were used to determine the association between demographic, obstetrical, psychosocial, medical, behavioral, and infant factors on childhood anxiety. Results Risk factors for childhood anxiety by age 5 included maternal psychological distress from birth to 12 months and 13 months to 5 years post-delivery and an infant 5-minute Apgar score of ≤7. Factors associated with decreased risk included maternal age < 20 years, multiparity, and preterm birth. Conclusion Identifying predictors of childhood anxiety is a key step to early detection and prevention. Maternal psychological distress is an early, modifiable risk factor. Future research should aim to disentangle early life influences on childhood anxiety occurring in the prenatal, postnatal, and early childhood periods. PMID:26158268

  9. A Study of Central Auction Based Wholesale Electricity Markets

    NASA Astrophysics Data System (ADS)

    Ceppi, Sofia; Gatti, Nicola

    The deregulation of electricity markets produced significant economic benefits, reducing prices to customers and opening several opportunities for new actors, e.g., new generators and distributors. A prominent scientific and technological challenge is the automation of such markets. In particular, we focus our attention on wholesale electricity markets based on a central auction. In these markets, generators sell electricity by means of a central auction to a public authority. Instead, the distribution of electricity to customers takes part in retail markets. The main works presented in the literature model wholesale markets as oligopolies, neglecting thus the specific auction mechanism. In this paper, we enrich these models by introducing an auction mechanism shaped on that used in the Italian wholesale electricity market, we solve the winner determination problem, and we preliminarily study the problem of searching for equilibria.

  10. Computational Study of Monosubstituted Azo(tetrazolepentazolium)-Based Ionic Dimers.

    PubMed

    Pimienta, Ian S O

    2015-06-04

    The structures of monosubstituted azo(tetrazolepentazolium) cations (N11CHR(+)), oxygen-rich anions such as N(NO2)2(-), NO3(-), and ClO4(-), and the corresponding ion pairs are investigated using ab initio quantum chemistry calculations. The substituents (R) used are H, F, CH3, CN, NH2, OH, OCH3, N3, NF2, and C2H3. The stability of the protonated cation is explored by examining the decomposition pathway of the protonated cation (N11CH2(+)) to yield molecular N2 fragments. The heats of formation of these cations, which are based on isodesmic (bond type conserving) reactions, are dependent on the nature of the substituents. Ionic dimer structures are obtained, but side reactions including proton transfer, binding, and hydrogen bonding are observed in the gas phase. Implicit solvation studies are performed to determine the solution properties of the ion pairs.

  11. Clinic-based intervention to promote literacy. A pilot study.

    PubMed

    Needlman, R; Fried, L E; Morley, D S; Taylor, S; Zuckerman, B

    1991-08-01

    Educational research has shown that children become literate more easily if their parents read to them. A clinic-based program was designed to encourage early book use among parents of children at risk. It included (1) waiting room readers, (2) guidance about literacy development, and (3) provision of children's books at each visit. Seventy-nine parents of children aged 6 to 60 months were interviewed. Parents who had previously received a book were more likely to report looking at books with their children or that looking at books was a favorite activity (adjusted odds ratio, 4.05). This association was strongest among parents receiving Aid to Families With Dependent Children (odds ratio, 7.8). This preliminary study suggests that pediatricians can play a role in enriching children's early literacy environments, especially for children at high risk of school failure.

  12. Atomic softness-based QSAR study of testosterone

    NASA Astrophysics Data System (ADS)

    Srivastava, H. K.; Pasha, F. A.; Singh, P. P.

    Ionization potential of an atom in a molecule, electron affinity of an atom in a molecule, and quantum chemical descriptor atomic softness values En‡-based quantitative structure-activity relationship (QSAR) study of testosterone derivatives have been done with the help of PM3 calculations on WinMOPAC 7.21 software. The 3D modeling and geometry optimization of all the compounds have been done with the help of PCMODEL software. The biological activities of testosterone derivatives have been taken from literature. The predicted values of biological activity with the help of multiple linear regression (MLR) analysis is very close to observed biological activity. The cross-validation coefficient and correlation coefficient also indicate that the QSAR model is valuable. Regression analysis shows a very good relationship with biological activity and En‡ values. With the help of these values, prediction of the biological activity of any unknown compound is possible.

  13. Study of a smart platform based on backstepping control method

    NASA Astrophysics Data System (ADS)

    Li, Luyu; Cheng, Baowei; Zhang, Yu; Qin, Han

    2017-07-01

    A structural model is significant for the verification of structural control algorithms. However, for nonlinear behavior, experiments are mostly destructive tests that are costly, and conducting repetitive structural experiments is difficult. Therefore, a repetitive structural vibration model is important for structural vibration control. In this study, a smart platform to realize different structural behaviors is developed based on the backstepping control algorithm. Lyapunov functions are used to derive the control law. Simulations show that the designed model can track the structural responses of different arbitrary linear structures very well. In addition, the proposed platform can track responses of different piecewise linear structures and desired models with various hysteresis very well. Numerical results verify the effectiveness of the proposed tracking controller through the backstepping method for the established platform.

  14. Active, LCoS based laser interferometer for microelements studies

    NASA Astrophysics Data System (ADS)

    Kacperski, Jacek; Kujawinska, Malgorzata

    2006-10-01

    The modification of classical Twyman-Green interferometer by implementation of Liquid Crystal on Silicon (LCoS) spatial light modulator as the reference mirror allows introducing arbitrary phase in the reference wavefront. This special capability is applied to facilitate the measurements of shape and deformation of active microelements and extend the range of such measurement. This can be realized by introducing linear or circular spatial carrier frequency into interferogram or by compensating object wavefront deformation. Moreover LCoS display can be used as an accurate phase shifter if the proper calibration is introduced. The analysis of sources of measurement errors introduced by LCoS display is presented and the ways of their elimination are discussed. The possible application of LCoS based laser interferometer for initial microelement shape determination and transient deformation monitoring as well as active reference phase modification are shown and experimentally confirmed during silicon micromembranes studies.

  15. Active, LCoS based laser interferometer for microelements studies.

    PubMed

    Kacperski, Jacek; Kujawinska, Malgorzata

    2006-10-16

    The modification of classical Twyman-Green interferometer by implementation of Liquid Crystal on Silicon (LCoS) spatial light modulator as the reference mirror allows introducing arbitrary phase in the reference wavefront. This special capability is applied to facilitate the measurements of shape and deformation of active microelements and extend the range of such measurement. This can be realized by introducing linear or circular spatial carrier frequency into interferogram or by compensating object wavefront deformation. Moreover LCoS display can be used as an accurate phase shifter if the proper calibration is introduced. The analysis of sources of measurement errors introduced by LCoS display is presented and the ways of their elimination are discussed. The possible application of LCoS based laser interferometer for initial microelement shape determination and transient deformation monitoring as well as active reference phase modification are shown and experimentally confirmed during silicon micromembranes studies.

  16. Kinetic study on urea uptake with chitosan based sorbent materials.

    PubMed

    Xue, Chen; Wilson, Lee D

    2016-01-01

    A one-pot kinetic uptake study of urea in aqueous solution with various chitosan sorbent materials such as pristine chitosan, cross-linked chitosan with glutaraldehyde from low (C-1) to higher (C-2) glutaraldehyde content, and a Cu(II) complex of a glutaraldehyde cross-linked chitosan material (C-3) is reported herein. The kinetic uptake profiles were analyzed by the pseudo-first order (PFO) and pseudo-second-order (PSO) models, respectively. The uptake rate constant of urea and the sorption capacity (qe) of high molecular weight (HMW) chitosan, C-1, C-2, and C-3 were best described by the PFO model. The uptake rate constant of urea with the various sorbents is listed in ascending order: HMW chitosanbased on scanning electron microscopy studies. These results further illustrate the rational design of chitosan-based materials for the controlled uptake of urea in aquatic environments. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Sensitivity studies for a space-based methane lidar mission

    NASA Astrophysics Data System (ADS)

    Kiemle, C.; Quatrevalet, M.; Ehret, G.; Amediek, A.; Fix, A.; Wirth, M.

    2011-10-01

    Methane is the third most important greenhouse gas in the atmosphere after water vapour and carbon dioxide. A major handicap to quantify the emissions at the Earth's surface in order to better understand biosphere-atmosphere exchange processes and potential climate feedbacks is the lack of accurate and global observations of methane. Space-based integrated path differential absorption (IPDA) lidar has potential to fill this gap, and a Methane Remote Lidar Mission (MERLIN) on a small satellite in polar orbit was proposed by DLR and CNES in the frame of a German-French climate monitoring initiative. System simulations are used to identify key performance parameters and to find an advantageous instrument configuration, given the environmental, technological, and budget constraints. The sensitivity studies use representative averages of the atmospheric and surface state to estimate the measurement precision, i.e. the random uncertainty due to instrument noise. Key performance parameters for MERLIN are average laser power, telescope size, orbit height, surface reflectance, and detector noise. A modest-size lidar instrument with 0.45 W average laser power and 0.55 m telescope diameter on a 506 km orbit could provide 50-km averaged methane column measurement along the sub-satellite track with a precision of about 1% over vegetation. The use of a methane absorption trough at 1.65 μm improves the near-surface measurement sensitivity and vastly relaxes the wavelength stability requirement that was identified as one of the major technological risks in the pre-phase A studies for A-SCOPE, a space-based IPDA lidar for carbon dioxide at the European Space Agency. Minimal humidity and temperature sensitivity at this wavelength position will enable accurate measurements in tropical wetlands, key regions with largely uncertain methane emissions. In contrast to actual passive remote sensors, measurements in Polar Regions will be possible and biases due to aerosol layers and thin

  18. Sensitivity studies for a space-based methane lidar mission

    NASA Astrophysics Data System (ADS)

    Kiemle, C.; Quatrevalet, M.; Ehret, G.; Amediek, A.; Fix, A.; Wirth, M.

    2011-06-01

    Methane is the third most important greenhouse gas in the atmosphere after water vapour and carbon dioxide. A major handicap to quantify the emissions at the Earth's surface in order to better understand biosphere-atmosphere exchange processes and potential climate feedbacks is the lack of accurate and global observations of methane. Space-based integrated path differential absorption (IPDA) lidar has potential to fill this gap, and a Methane Remote Lidar Mission (MERLIN) on a small satellite in Polar orbit was proposed by DLR and CNES in the frame of a German-French climate monitoring initiative. System simulations are used to identify key performance parameters and to find an advantageous instrument configuration, given the environmental, technological, and budget constraints. The sensitivity studies use representative averages of the atmospheric and surface state to estimate the measurement precision, i.e. the random uncertainty due to instrument noise. Key performance parameters for MERLIN are average laser power, telescope size, orbit height, surface reflectance, and detector noise. A modest-size lidar instrument with 0.45 W average laser power and 0.55 m telescope diameter on a 506 km orbit could provide 50-km averaged methane column measurement along the sub-satellite track with a precision of about 1 % over vegetation. The use of a methane absorption trough at 1.65 μm improves the near-surface measurement sensitivity and vastly relaxes the wavelength stability requirement that was identified as one of the major technological risks in the pre-phase A studies for A-SCOPE, a space-based IPDA lidar for carbon dioxide at the European Space Agency. Minimal humidity and temperature sensitivity at this wavelength position will enable accurate measurements in tropical wetlands, key regions with largely uncertain methane emissions. In contrast to actual passive remote sensors, measurements in Polar Regions will be possible and biases due to aerosol layers and thin

  19. Source mask optimization study based on latest Nikon immersion scanner

    NASA Astrophysics Data System (ADS)

    Zhu, Jun; Wei, Fang; Chen, Lijun; Zhang, Chenming; Zhang, Wei; Nishinaga, Hisashi; El-Sewefy, Omar; Gao, Gen-Sheng; Lafferty, Neal; Meiring, Jason; Zhang, Recoo; Zhu, Cynthia

    2016-03-01

    The 2x nm logic foundry node has many challenges since critical levels are pushed close to the limits of low k1 ArF water immersion lithography. For these levels, improvements in lithographic performance can translate to decreased rework and increased yield. Source Mask Optimization (SMO) is one such route to realize these image fidelity improvements. During SMO, critical layout constructs are intensively optimized in both the mask and source domain, resulting in a solution for maximum lithographic entitlement. From the hardware side, advances in source technology have enabled free-form illumination. The approach allows highly customized illumination, enabling the practical application of SMO sources. The customized illumination sources can be adjusted for maximum versatility. In this paper, we present a study on a critical layer of an advanced foundry logic node using the latest ILT based SMO software, paired with state-of-the-art scanner hardware and intelligent illuminator. Performance of the layer's existing POR source is compared with the ideal SMO result and the installed source as realized on the intelligent illuminator of an NSR-S630D scanner. Both simulation and on-silicon measurements are used to confirm that the performance of the studied layer meets established specifications.

  20. Outpatient- and inpatient-based buckling surgery: a comparative study

    PubMed Central

    Lee, Jin Cheol; Kim, Yu Cheol

    2014-01-01

    Purpose To evaluate the clinical outcomes of ambulatory buckling surgery, comparing outpatient- with inpatient-based surgery. Methods The authors performed a retrospective study of 80 consecutive cases of rhegmato genous retinal detachment from January 2009 to December 2011 treated by scleral buckling surgery. Two groups of patients were defined according to inpatient (group 1) or outpatient (group 2) surgery, and a comparison of several parameters between these two groups was performed. Results Of the 80 subjects in this study, the average age of group 1 (50 patients) was 49.7 years, and that of group 2 (30 patients) was 47.5 years. There were no statistically significant differences in the average logarithm of the minimum angle of resolution-visual acuity, the condition of the lens, or the presence of retinal lattice degeneration prior to the surgery between the groups. There were no statistically significant differences in the patterns of tear or retinal detachment or in surgical procedure between the groups. Comparing the best-corrected visual acuity after 6 months with that prior to the surgery, the changes in group 1 and group 2 were 0.26 and 0.31, respectively. The functional success rates of group 1 and group 2 after 6 months were 90% and 93%, respectively, and the anatomical success rates of group 1 and group 2 after 6 months were 94% and 96%, respectively, but these were also statistically insignificant. Conclusion Hospitalization is not essential for buckling surgery in uncomplicated rhegmatogenous retinal detachment surgery. PMID:24812485

  1. Space-based solar power conversion and delivery systems study

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Even at reduced rates of growth, the demand for electric power is expected to more than triple between now and 1995, and to triple again over the period 1995-2020. Without the development of new power sources and advanced transmission technologies, it may not be possible to supply electric energy at prices that are conductive to generalized economic welfare. Solar power is renewable and its conversion and transmission from space may be advantageous. The goal of this study is to assess the economic merit of space-based photovoltaic systems for power generation and a power relay satellite for power transmission. In this study, satellite solar power generation and transmission systems, as represented by current configurations of the Satellite Solar Station (SSPS) and the Power Relay Satellite (PRS), are compared with current and future terrestrial power generation and transmission systems to determine their technical and economic suitability for meeting power demands in the period of 1990 and beyond while meeting ever-increasing environmental and social constraints.

  2. Study of carbon nanotubes based Polydimethylsiloxane composite films

    NASA Astrophysics Data System (ADS)

    Shahzad, M. I.; Giorcelli, M.; Shahzad, N.; Guastella, S.; Castellino, M.; Jagdale, P.; Tagliaferro, A.

    2013-06-01

    Thanks to their remarkable characteristics, carbon nanotubes (CNTs) have fields of applications which are growing every day. Among them, the use of CNTs as filler for polymers is one of the most promising. In this work we report on Polydimethylsiloxane (PDMS) composites with different weight percentages (0.0% to 3.0%) of multiwall carbon nanotubes (MWCNTs) having diameter 10-30 nm and length 20-30 μm. To achieve optimum dispersion of CNTs in PDMS matrix, high speed mechanical stirring and ultrasonication were performed. By using the doctor blade technique, 70 μm thick uniform films were produced on glass. They were subsequently thermally cured and detached from the glass to get flexible and self standing films. The surface morphological study done by FESEM, shows that CNTs are well dispersed in the PDMS. Raman spectroscopy and FTIR were used to investigate the possible structural changes in the polymer composite. To examine the optical behavior UV-VIS spectroscopy was employed in both specular and diffused modes. A linear increase in absorption coefficient is found with the increasing percentage of CNTs while the transmittance decreases exponentially. The results confirm the dependence of optical limiting effect on the quantity of MWCNTs. Based on optical study, MWCNTs/PDMS composite films can be a promising material to extend performances of optical limiters against laser pulses, which is often required in lasing systems.

  3. Stress and dysmenorrhoea: a population based prospective study

    PubMed Central

    Wang, L; Wang, X; Wang, W; Chen, C; Ronnennberg, A; Guang, W; Huang, A; Fang, Z; Zang, T; Wang, L; Xu, X

    2004-01-01

    Background: Dysmenorrhoea is the most common gynaecological disorder in women of reproductive age. Despite the association between stress and pregnancy outcomes, few studies have examined the possible link between stress and dysmenorrhoea. Aims and Methods: Using a population based cohort of Chinese women, the independent effect of women's perceived stress in the preceding menstrual cycle on the incidence of dysmenorrhoea in the subsequent cycle was investigated prospectively. The analysis included 1160 prospectively observed menstrual cycles from 388 healthy, nulliparous, newly married women who intended to conceive. The perception of stress and the occurrence of dysmenorrhoea in each menstrual cycle were determined from daily diaries recorded by the women. Results: After adjustment for important covariates, the risk of dysmenorrhoea was more than twice as great among women with high stress compared to those with low stress in the preceding cycle (OR = 2.4; 95% CI 1.4 to 4.3). The risk of dysmenorrhoea was greatest among women with both high stress and a history of dysmenorrhoea compared to women with low stress and no history of dysmenorrhoea (OR = 10.4, 95% CI 4.9 to 22.3). Stress in the follicular phase of the preceding cycles had a stronger association with dysmenorrhoea than stress in the luteal phase of the preceding cycles. Conclusion: This study shows a significant association between stress and the incidence of dysmenorrhoea, which is even stronger among women with a history of dysmenorrhoea. PMID:15550609

  4. Calculation and Study of Graphene Conductivity Based on Terahertz Spectroscopy

    NASA Astrophysics Data System (ADS)

    Feng, Xiaodong; Hu, Min; Zhou, Jun; Liu, Shenggang

    2017-07-01

    Based on terahertz time-domain spectroscopy system and two-dimensional scanning control system, terahertz transmission and reflection intensity mapping images on a graphene film are obtained, respectively. Then, graphene conductivity mapping images in the frequency range 0.5 to 2.5 THz are acquired according to the calculation formula. The conductivity of graphene at some typical regions is fitted by Drude-Smith formula to quantitatively compare the transmission and reflection measurements. The results show that terahertz reflection spectroscopy has a higher signal-to-noise ratio with less interference of impurities on the back of substrates. The effect of a red laser excitation on the graphene conductivity by terahertz time-domain transmission spectroscopy is also studied. The results show that the graphene conductivity in the excitation region is enhanced while that in the adjacent area is weakened which indicates carriers transport in graphene under laser excitation. This paper can make great contribution to the study on graphene electrical and optical properties in the terahertz regime and help design graphene terahertz devices.

  5. Synthesis, structural and fungicidal studies of hydrazone based coordination compounds

    NASA Astrophysics Data System (ADS)

    Sharma, Amit Kumar; Chandra, Sulekh

    2013-02-01

    The coordination compounds of the Co(II), Ni(II) and Cu(II) metal ions derived from imine based ligand, benzil bis(carbohydarzone) were structurally and pharmaceutically studied. The compounds have the general stoichiometry [M(L)]X2 and [Co(L)X2], where M = Ni(II) and Cu(II), and X=NO3- and Cl- ions. The analytical techniques like elemental analyses, molar conductance measurements, magnetic susceptibility measurements, IR, UV/Visible, NMR, ESI mass and EPR were used to study the compounds. The key IR bands, i.e., amide I, amide II and amide III stretching vibrations accounts for the tetradentate metal binding nature of the ligand. The electronic and EPR spectral results suggest the square planar Ni(II) and Cu(II) complexes (giso = 2.11-2.22) and tetragonal geometry Co(II) complexes (giso = 2.10-2.17). To explore the compounds in the biological field, they were examined against the opportunistic pathogens, i.e., Alternaria brassicae, Aspergillus niger and Fusarium oxysporum. The partial covalent character of metal-ligand bond is supported by the orbital reduction factor k (0.62-0.92) and nephalauxetic parameter β (0.55-0.57).

  6. AUV based study on physical and ecological processes at fronts

    NASA Astrophysics Data System (ADS)

    Tippenhauer, Sandra; Wulff, Thorben; Von Appen, Wilken-Jon

    2017-04-01

    Small-scale processes and their effects get more and more attention when it comes to understanding processes and changes in the (Arctic) ocean. Here we present a study on physical processes and ecological responses at submesoscale frontal systems in the Fram Strait investigated using an autonomous underwater vehicle (AUV). The AUV is equipped with physical and biogeochemical sensors such as an acoustic Doppler current profiler, a turbulence probe, a conductivity-temperature-depth probe, and sensors for Oxygen, Nitrate, Chlorophyll a, and photosynthetically active radiation (PAR). The study is designed such that the AUV covers tracks of several kilometers length in cross-frontal direction with the front roughly located in the middle of the track. On its way, the AUV records high-resolution vertical or zigzag profiles of the physical and biogeochemical properties in the upper 50 m which includes the euphotic zone. In both, physical and biogeochemical terms, the measurements revealed a complex structure of the water column. At the fronts the distribution of phytoplankton and nutrients was highly inhomogeneous, possibly due to wind-driven frontogenesis or the growth of mixed layer eddies. To set the observations into a larger context we also examine ship-based and satellite data. We investigate how the observed patterns of the potential vorticity and the biogeochemical properties may be formed and which processes could lead to a smoothing of the observed gradients.

  7. Diabetes mellitus in North West Ethiopia: a community based study

    PubMed Central

    2014-01-01

    Background Diabetes mellitus is recognized as one of the emerging public health problems in developing countries. However, its magnitude has not been studied at community levels, making the provision of appropriate services difficult in such countries. Hence, this study aimed to compare the magnitude and associated risks of diabetes mellitus among urban and rural adults in northwest Ethiopia. Methods A cross-sectional population based survey was performed using the WHO STEPwise method on adults aged 35 years and above. A multistage cluster random sampling strategy was used to select study participants from urban and rural locations. Fasting blood glucose levels were determined using peripheral blood samples by finger puncture. Prevalence was computed with a 95% confidence interval for each residential area. Selected risk factors were assessed using logistic regression. Results The prevalence of diabetes mellitus among adults aged 35 years and above was 5.1% [95% CI: 3.8, 6.4] for urban and 2.1% [95% CI: 1.2, 2.9] for rural dwellers. The majority (69%) of the identified diabetic cases were not diagnosed prior to the survey. The highest proportion (82.6%) of the undiagnosed cases was noted among the rural population and 63% among the urban population. Family history of diabetes (AOR = 5.05; 2.43, 10.51), older age (AOR = 4.86; 1.99, 11.9) and physical inactivity (AOR = 1.92; 1.06, 3.45) were significantly associated with diabetes mellitus among the urban population. Alcohol consumption (AOR = 0 .24, 0 .06, 0.99) was inversely associated with diabetes mellitus in rural areas. Conclusion The prevalence of diabetes mellitus is considerably high among the urban compared to the rural population. Diabetes is largely undiagnosed and untreated, especially in rural settings. Appropriate actions need to be taken to provide access to early diagnosis and treatment in order to reduce associated complications. PMID:24479725

  8. Population-based study of presbyopia in Shahroud, Iran.

    PubMed

    Hashemi, Hassan; Khabazkhoob, Mehdi; Jafarzadehpur, Ebrahim; Mehravaran, Shiva; Emamian, Mohammad Hassan; Yekta, AbbasAli; Shariati, Mohammad; Fotouhi, Akbar

    2012-12-01

    There is limited information regarding the prevalence of presbyopia in different parts of the world. The add power and the prevalence of presbyopia by age and gender in general population of Shahroud, north of Iran, were studied. Population-based cross-sectional study. Using random cluster sampling, 6311 people from the 40- to 64-year-old population of Shahroud were invited. Of the invited population, 5190 individuals (82.2%) participated in the study. Presbyopia was defined as the correction of near vision to logMAR 1 (N8 point) with at least 1 D of add power. Near visual acuity of participants was evaluated with a logMAR chart at a distance of 40 cm. Mean add power in the age groups of 40-44, 45-49, 50-54, 55-59 and 60-64 years was 0.65, 1.30, 1.70, 1.87 and 2.08 D, respectively. For each 5-year increase in age, a 0.35 D increase in add power was noted. The prevalence of presbyopia was 58.15% (95% confidence interval: 56.46-59.84). Presbyopia was more prevalent in women (P < 0.001) and increased with ageing more in women than in men (P < 0.001). Furthermore, in the 60-64-year-old age group, 11% of men and 23% of women were not presbyopic. Compared with other reports, the add power in different age groups was 0.5 D less, and presbyopia was less prevalent. More than 50% of the over 45-year-old individuals were presbyopic and 17% of the over 60 individuals were free of this condition. © 2012 The Authors. Clinical and Experimental Ophthalmology © 2012 Royal Australian and New Zealand College of Ophthalmologists.

  9. Diabetes mellitus in North West Ethiopia: a community based study.

    PubMed

    Abebe, Solomon Mekonnen; Berhane, Yemane; Worku, Alemayehu; Assefa, Abebayehu

    2014-01-30

    Diabetes mellitus is recognized as one of the emerging public health problems in developing countries. However, its magnitude has not been studied at community levels, making the provision of appropriate services difficult in such countries. Hence, this study aimed to compare the magnitude and associated risks of diabetes mellitus among urban and rural adults in northwest Ethiopia. A cross-sectional population based survey was performed using the WHO STEPwise method on adults aged 35 years and above. A multistage cluster random sampling strategy was used to select study participants from urban and rural locations. Fasting blood glucose levels were determined using peripheral blood samples by finger puncture. Prevalence was computed with a 95% confidence interval for each residential area. Selected risk factors were assessed using logistic regression. The prevalence of diabetes mellitus among adults aged 35 years and above was 5.1% [95% CI: 3.8, 6.4] for urban and 2.1% [95% CI: 1.2, 2.9] for rural dwellers. The majority (69%) of the identified diabetic cases were not diagnosed prior to the survey. The highest proportion (82.6%) of the undiagnosed cases was noted among the rural population and 63% among the urban population. Family history of diabetes (AOR = 5.05; 2.43, 10.51), older age (AOR = 4.86; 1.99, 11.9) and physical inactivity (AOR = 1.92; 1.06, 3.45) were significantly associated with diabetes mellitus among the urban population. Alcohol consumption (AOR = 0 .24, 0 .06, 0.99) was inversely associated with diabetes mellitus in rural areas. The prevalence of diabetes mellitus is considerably high among the urban compared to the rural population. Diabetes is largely undiagnosed and untreated, especially in rural settings. Appropriate actions need to be taken to provide access to early diagnosis and treatment in order to reduce associated complications.

  10. Astigmatism in underserved rural areas: a population based study.

    PubMed

    Hashemi, Hassan; Nabovati, Payam; Malekifar, Azam; Yekta, Abbasali; Ostadimoghaddam, Hadi; Jafarzadehpur, Ebrahim; Khabazkhoob, Mehdi

    2016-11-01

    Studying the prevalence of astigmatism and its related factors in underprivileged rural areas in Iran. Using random cluster sampling, two rural areas in the north and southwest of Iran were randomly selected, and 3851 persons over 1 year of age were invited to the study. In addition to recording demographics, retinoscopic refraction was conducted using baseline auto-refraction results. The prevalence of astigmatism was determined based on cylinder error cut-off points of 0.50 dioptre (D), 1.00, 2.00 and 3.00 D. Multiple logistic regression was used to assess variables' relationship with astigmatism. The prevalence of astigmatism as a cylinder error greater than 0.50 D was 35.6% (95% CI: 33.7-37.6); this was 34.0% (95% CI: 31.4-36.6) in women and 36.9% (95% CI: 33.9-39.9) in men. The lowest prevalence was seen in the 6-20 year old age group (13.6%) and the highest prevalence was found in individuals older than 70 years (82.5%). In the multiple logistic regression model, age and education level were significantly related to astigmatism. The prevalence rates of with-the-rule (WTR), against-the-rule (ATR), and oblique astigmatism were respectively 15.0%, 17.2%, and 3.5%. The prevalence of WTR astigmatism decreased with age, while the prevalence of ATR (and oblique astigmatism to a lesser extent) increased. The prevalence of astigmatism was similar to previous studies; however, there were considerable age-related changes. In particular, the prevalence of astigmatism in elderly people was substantial and of concern, particularly given that virtually none of this age group were wearing distance spectacles. © 2016 The Authors Ophthalmic & Physiological Optics © 2016 The College of Optometrists.

  11. Agenda-based regulation of study-time allocation: when agendas override item-based monitoring.

    PubMed

    Ariel, Robert; Dunlosky, John; Bailey, Heather

    2009-08-01

    Theories of self-regulated study assume that learners monitor item difficulty when making decisions about which items to select for study. To complement such theories, the authors propose an agenda-based regulation (ABR) model in which learners' study decisions are guided by an agenda that learners develop to prioritize items for study, given their goals and task constraints. Across 4 experiments, the authors orthogonally manipulated 1 task constraint-the reward structure of the task-with objective item difficulty, so that learners could use either item difficulty or potential reward in deciding how to allocate their study time. Learners studied items, were tested, and then selected half the items for restudy. As predicted by the ABR model, reward structure drove item selection more than did item difficulty, which demonstrates learners' agendas can override the effects of monitoring item difficulty in the allocation of study time.

  12. Space-based laser-driven MHD generator: Feasibility study

    NASA Technical Reports Server (NTRS)

    Choi, S. H.

    1986-01-01

    The feasibility of a laser-driven MHD generator, as a candidate receiver for a space-based laser power transmission system, was investigated. On the basis of reasonable parameters obtained in the literature, a model of the laser-driven MHD generator was developed with the assumptions of a steady, turbulent, two-dimensional flow. These assumptions were based on the continuous and steady generation of plasmas by the exposure of the continuous wave laser beam thus inducing a steady back pressure that enables the medium to flow steadily. The model considered here took the turbulent nature of plasmas into account in the two-dimensional geometry of the generator. For these conditions with the plasma parameters defining the thermal conductivity, viscosity, electrical conductivity for the plasma flow, a generator efficiency of 53.3% was calculated. If turbulent effects and nonequilibrium ionization are taken into account, the efficiency is 43.2%. The study shows that the laser-driven MHD system has potential as a laser power receiver for space applications because of its high energy conversion efficiency, high energy density and relatively simple mechanism as compared to other energy conversion cycles.

  13. Electrical studies on silver based fast ion conducting glassy materials

    SciTech Connect

    Rao, B. Appa Kumar, E. Ramesh Kumari, K. Rajani Bhikshamaiah, G.

    2014-04-24

    Among all the available fast ion conductors, silver based glasses exhibit high conductivity. Further, glasses containing silver iodide enhances fast ion conducting behavior at room temperature. Glasses of various compositions of silver based fast ion conductors in the AgI−Ag{sub 2}O−[(1−x)B{sub 2}O{sub 3}−xTeO{sub 2}] (x=0 to1 mol% in steps of 0.2) glassy system have been prepared by melt quenching method. The glassy nature of the compounds has been confirmed by X-ray diffraction. The electrical conductivity (AC) measurements have been carried out in the frequency range of 1 KHz–3MHz by Impedance Analyzer in the temperature range 303–423K. The DC conductivity measurements were also carried out in the temperature range 300–523K. From both AC and DC conductivity studies, it is found that the conductivity increases and activation energy decreases with increasing the concentration of TeO{sub 2} as well as with temperature. The conductivity of the present glass system is found to be of the order of 10{sup −2} S/cm at room temperature. The ionic transport number of these glasses is found to be 0.999 indicating that these glasses can be used as electrolyte in batteries.

  14. Chromatographic Studies of Protein-Based Chiral Separations.

    PubMed

    Bi, Cong; Zheng, Xiwei; Azaria, Shiden; Beeram, Sandya; Li, Zhao; Hage, David S

    2016-09-01

    The development of separation methods for the analysis and resolution of chiral drugs and solutes has been an area of ongoing interest in pharmaceutical research. The use of proteins as chiral binding agents in high-performance liquid chromatography (HPLC) has been an approach that has received particular attention in such work. This report provides an overview of proteins that have been used as binding agents to create chiral stationary phases (CSPs) and in the use of chromatographic methods to study these materials and protein-based chiral separations. The supports and methods that have been employed to prepare protein-based CSPs will also be discussed and compared. Specific types of CSPs that are considered include those that employ serum transport proteins (e.g., human serum albumin, bovine serum albumin, and alpha1-acid glycoprotein), enzymes (e.g., penicillin G acylase, cellobiohydrolases, and α-chymotrypsin) or other types of proteins (e.g., ovomucoid, antibodies, and avidin or streptavidin). The properties and applications for each type of protein and CSP will also be discussed in terms of their use in chromatography and chiral separations.

  15. Secured web-based video repository for multicenter studies.

    PubMed

    Yan, Ling; Hicks, Matt; Winslow, Korey; Comella, Cynthia; Ludlow, Christy; Jinnah, H A; Rosen, Ami R; Wright, Laura; Galpern, Wendy R; Perlmutter, Joel S

    2015-04-01

    We developed a novel secured web-based dystonia video repository for the Dystonia Coalition, part of the Rare Disease Clinical Research network funded by the Office of Rare Diseases Research and the National Institute of Neurological Disorders and Stroke. A critical component of phenotypic data collection for all projects of the Dystonia Coalition includes a standardized video of each participant. We now describe our method for collecting, serving and securing these videos that is widely applicable to other studies. Each recruiting site uploads standardized videos to a centralized secured server for processing to permit website posting. The streaming technology used to view the videos from the website does not allow downloading of video files. With appropriate institutional review board approval and agreement with the hosting institution, users can search and view selected videos on the website using customizable, permissions-based access that maintains security yet facilitates research and quality control. This approach provides a convenient platform for researchers across institutions to evaluate and analyze shared video data. We have applied this methodology for quality control, confirmation of diagnoses, validation of rating scales, and implementation of new research projects. We believe our system can be a model for similar projects that require access to common video resources. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Study of Trade Wind Clouds Using Ground Based Stereo Cameras

    NASA Astrophysics Data System (ADS)

    Porter, J.

    2010-12-01

    We employ ground based stereo cameras to derive the three dimensional position of trade wind clouds features. The process employs both traditional and novel methods. The stereo cameras are calibrated for orientation using the sun as a geo-reference point at several times throughout the day. Spatial correlation is used to detect similar cloud features in both camera images and a simultaneous-differential equation is solved to get the best cloud position for the given rays from the cameras to the cloud feature. Once the positions of the clouds are known in three-dimensional space, then it is also possible to derive upper level wind speed and direction by tracking the position of clouds in space and time. The vector winds can be obtained at many locations and heights in a cone region over the surface site. The accuracy of the measurement depends on the camera separation with a trade-off occurring at different camera separations and cloud ranges. The system design and performance will be discussed along with field observations. This approach provides a new way to study clouds for climate change efforts. It also provides an inexpensive way to measure upper level wind fields in cloudy regions. Ground based stereo cameras are used to derive cloud position in space a time.

  17. Secured web-based video repository for multicenter studies

    PubMed Central

    Yan, Ling; Hicks, Matt; Winslow, Korey; Comella, Cynthia; Ludlow, Christy; Jinnah, H. A; Rosen, Ami R; Wright, Laura; Galpern, Wendy R; Perlmutter, Joel S

    2015-01-01

    Background We developed a novel secured web-based dystonia video repository for the Dystonia Coalition, part of the Rare Disease Clinical Research network funded by the Office of Rare Diseases Research and the National Institute of Neurological Disorders and Stroke. A critical component of phenotypic data collection for all projects of the Dystonia Coalition includes a standardized video of each participant. We now describe our method for collecting, serving and securing these videos that is widely applicable to other studies. Methods Each recruiting site uploads standardized videos to a centralized secured server for processing to permit website posting. The streaming technology used to view the videos from the website does not allow downloading of video files. With appropriate institutional review board approval and agreement with the hosting institution, users can search and view selected videos on the website using customizable, permissions-based access that maintains security yet facilitates research and quality control. Results This approach provides a convenient platform for researchers across institutions to evaluate and analyze shared video data. We have applied this methodology for quality control, confirmation of diagnoses, validation of rating scales, and implementation of new research projects. Conclusions We believe our system can be a model for similar projects that require access to common video resources. PMID:25630890

  18. Defect-based graphene nanoribbon photodetectors: A numerical study

    SciTech Connect

    Zarei, M. H.; Sharifi, M. J.

    2016-06-07

    Recently, some photodetectors based on graphene have been proposed. In all of these works, current generation was carried out by separation of photo-excited carriers using an electric field, either internal or external. In this work, a new method of producing current which is based on different transmission coefficients for electrons and holes when they travel toward any of the two contacts is proposed. To this end, a single Stone–Wales defect close to one of the two contacts was used to break the channel symmetry. In order to confirm the idea, the non-equilibrium Green's function formalism in real space in conjunction with the tight binding method was used in simulations. In addition, to clarify the results, we present a classical model in which different diffusion constants are assumed for the left going and the right going carriers. Additional simulations for different positions of the defect, different lengths of the ribbon, and different bias voltages were performed, and the results are included in this study.

  19. Novel dipodal Schiff base compounds: Synthesis, characterization and spectroscopic studies

    NASA Astrophysics Data System (ADS)

    Obali, Aslihan Yilmaz; Ucan, Halil Ismet

    2015-02-01

    Two novel dipodal Schiff base compounds 1,2-benzyloxy-bis-[2-(benzylideneamino)phenol, L1 and 1,2-benzyloxy-bis[3-(benzylideneamino)pyridine], L2 were synthesized. Their sensing actions were confirmed by UV-Vis absorbance and emission spectroscopic studies in presence of Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Sn(II), Cd(II) and Pb(II) in methanol medium (1 × 10-4 M). It was found that the dipodal compounds can selectively bind to Cu(II) and Pb(II) metal ions with a significant change in its emission and absorption spectra, while the addition of other metal ions (Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Sn(II), Cd(II) and Pb(II)) produces insignificant or minor changes. The host-guest complexes formed were determined by Job's plot method. As a chemosensor, L1 and L2 dipodal Schiff base compounds shows a specific selectivity towards Cu(II) and Pb(II) ions in according to all spectroscopic data.

  20. Chromatographic Studies of Protein-Based Chiral Separations

    PubMed Central

    Bi, Cong; Zheng, Xiwei; Azaria, Shiden; Beeram, Sandya; Li, Zhao; Hage, David S.

    2016-01-01

    The development of separation methods for the analysis and resolution of chiral drugs and solutes has been an area of ongoing interest in pharmaceutical research. The use of proteins as chiral binding agents in high-performance liquid chromatography (HPLC) has been an approach that has received particular attention in such work. This report provides an overview of proteins that have been used as binding agents to create chiral stationary phases (CSPs) and in the use of chromatographic methods to study these materials and protein-based chiral separations. The supports and methods that have been employed to prepare protein-based CSPs will also be discussed and compared. Specific types of CSPs that are considered include those that employ serum transport proteins (e.g., human serum albumin, bovine serum albumin, and alpha1-acid glycoprotein), enzymes (e.g., penicillin G acylase, cellobiohydrolases, and α-chymotrypsin) or other types of proteins (e.g., ovomucoid, antibodies, and avidin or streptavidin). The properties and applications for each type of protein and CSP will also be discussed in terms of their use in chromatography and chiral separations. PMID:28344977

  1. Statistical Studies of Ground-Based Optical Lightning Signatures

    NASA Astrophysics Data System (ADS)

    Hunt, C. R.; Nemzek, R. J.; Suszcynsky, D. M.

    2005-12-01

    Most extensive optical studies of lightning have been conducted from orbit, and the statistics of events collected from earth are relatively poorly documented. The time signatures of optical power measured in the presence of clouds are inevitably affected by scattering,which can distort the signatures by extending and delaying the amplitude profile in time. We have deployed two all-sky photodiode detectors, one in New Mexico and one in Oklahoma, which are gathering data alongside electric field change monitors as part of the LANL EDOTX Great Plains Array. Preliminary results show that the photodiode is sensitive to approximately 50% or more of RF events detected at ranges of up to 30 km, and still has some sensitivity at ranges in excess of 60 km (distances determined by the EDOTX field-change array). The shapes of events within this range were assessed, with focus on rise time, width, peak power, and their correlation to corresponding electric field signatures, and these are being compared with published on-orbit and ground-based data. Initial findings suggest a mean characteristic width (ratio of total detected optical energy to peak power) of 291 +/- 12 microseconds and a mean delay between the RF signal peak and optical peak of 121 +/- 17 microseconds. These values fall between prior ground-based measurements of direct return stroke emissions, and scattering-dominated on-orbit measurements. This work will promote better understanding of the correspondence between radio and optical measurements of lightning.

  2. Study design in evidence-based surgery: What is the role of case-control studies?

    PubMed Central

    Cao, Amy M; Cox, Michael R; Eslick, Guy D

    2016-01-01

    Randomized controlled trials (RCTs) are the gold standard in terms of study design, however, in the surgical setting conducting RCTs can often be unethical or logistically impossible. Case-control studies should become the major study design used in surgical research when RCTs are unable to be conducted and definitely replacing case series which offer little insight into surgical outcomes and disease processes. PMID:27019801

  3. Research on Hygiene Based on Fieldwork and Experimental Studies.

    PubMed

    Yajima, Ichiro

    2017-01-01

    Several experimental studies on hygiene have recently been performed and fieldwork studies are also important and essential tools. However, the implementation of experimental studies is insufficient compared with that of fieldwork studies on hygiene. Here, we show our well-balanced implementation of both fieldwork and experimental studies of toxic-element-mediated diseases including skin cancer and hearing loss. Since the pollution of drinking well water by toxic elements induces various diseases including skin cancer, we performed both fieldwork and experimental studies to determine the levels of toxic elements and the mechanisms behind the development of toxic-element-related diseases and to develop a novel remediation system. Our fieldwork studies in several countries including Bangladesh, Vietnam and Malaysia demonstrated that drinking well water was polluted with high concentrations of several toxic elements including arsenic, barium, iron and manganese. Our experimental studies using the data from our fieldwork studies demonstrated that these toxic elements caused skin cancer and hearing loss. Further experimental studies resulted in the development of a novel remediation system that adsorbs toxic elements from polluted drinking water. A well-balanced implementation of both fieldwork and experimental studies is important for the prediction, prevention and therapy of toxic-element-mediated diseases.

  4. A study of acceptability & feasibility of integrating humanities based study modules in undergraduate curriculum

    PubMed Central

    Gurtoo, Anil; Ranjan, Piyush; Sud, Ritika; Kumari, Archana

    2013-01-01

    Background & objectives: The field of medical education in our country remains deeply fragmented and polarised between the biomedical technical domains which are overrepresented and the humanitarian domains which are under-represented within the universe of medical pedagogy. To overcome this imbalance, we designed a module that integrates the two domains in a holistic biomedical and socio-cultural framework with the objective of providing unified field of learning experience to the undergraduate medical students attending rotatory clinical postings in a medical college in New Delhi, India. Methods: Undergraduate medical students of 6th and 8th semesters were enrolled in humanities based study module (HSM) on voluntary basis for a total duration of six months. During their compulsory rotatory medicine ward posting, they were introduced and exposed to learning bedside experience of HSM with various tools of art and literature in the form of poem, short narratives, paintings, sketches and group discussions to express their feelings about patients’ sufferings. Students’ feed-back was recorded through an anonymized questionnaire. Result: Of the 235 students, 223 (95%) enrolled themselves voluntarily and 94 per cent (210 of 223) of them completed the total six month duration of the study module. Seventy three per cent of the students found HSM effective in improving their affective motivational behavior, 82 per cent found it effective in motivating them to learn more about core medical subjects, and 85 per cent wanted its continuation as part of medical curriculum. Interpretation & conclusions: The positive response of the students towards the HSM was an indicator of the potential for integrating the module within the undergraduate medical curriculum. PMID:23481073

  5. Distribution of conjunctival ultraviolet autoflourescence in a population-based study: the Norfolk Island Eye Study

    PubMed Central

    Sherwin, J C; Hewitt, A W; Kearns, L S; Coroneo, M T; Griffiths, L R; Mackey, D A

    2011-01-01

    Objective The objective of this study was to describe the distribution of conjunctival ultraviolet autofluorescence (UVAF) in an adult population. Methods We conducted a cross-sectional, population-based study in the genetic isolate of Norfolk Island, South Pacific Ocean. In all, 641 people, aged 15 to 89 years, were recruited. UVAF and standard (control) photographs were taken of the nasal and temporal interpalpebral regions bilaterally. Differences between the groups for non-normally distributed continuous variables were assessed using the Wilcoxon–Mann–Whitney ranksum test. Trends across categories were assessed using Cuzick's non-parametric test for trend or Kendall's rank correlation τ. Results Conjunctival UVAF is a non-parametric trait with a positively skewed distribution. Median amount of conjunctival UVAF per person (sum of four measurements; right nasal/temporal and left nasal/temporal) was 28.2 mm2 (interquartile range 14.5–48.2). There was an inverse, linear relationship between UVAF and advancing age (P<0.001). Males had a higher sum of UVAF compared with females (34.4 mm2 vs23.2 mm2, P<0.0001). There were no statistically significant differences in area of UVAF between right and left eyes or between nasal and temporal regions. Conclusion We have provided the first quantifiable estimates of conjunctival UVAF in an adult population. Further data are required to provide information about the natural history of UVAF and to characterise other potential disease associations with UVAF. UVR protective strategies should be emphasised at an early age to prevent the long-term adverse effects on health associated with excess UVR. PMID:21494284

  6. Parameterizations for shielding electron accelerators based on Monte Carlo studies

    SciTech Connect

    P. Degtyarenko; G. Stapleton

    1996-10-01

    Numerous recipes for designing lateral slab neutron shielding for electron accelerators are available and each generally produces rather similar results for shield thicknesses of about 2 m of concrete and for electron beams with energy in the 1 to 10 GeV region. For thinner or much thicker shielding the results tend to diverge and the standard recipes require modification. Likewise for geometries other than lateral to the beam direction further corrections are required so that calculated results are less reliable and hence additional and costly conservatism is needed. With the adoption of Monte Carlo (MC) methods of transporting particles a much more powerful way of calculating radiation dose rates outside shielding becomes available. This method is not constrained by geometry, although deep penetration problems need special statistical treatment, and is an excellent approach to solving any radiation transport problem providing the method has been properly checked against measurements and is free from the well known errors common to such computer methods. This present paper utilizes the results of MC calculations based on a nuclear fragmentation model named DINREG using the MC transport code GEANT and models them with the normal two parameter shielding expressions. Because the parameters can change with electron beam energy, angle to the electron beam direction and target material, the parameters are expressed as functions of some of these variables to provide a universal equations for shielding electron beams which can used rather simply for deep penetration problems in simple geometry without the time consuming computations needed in the original MC programs. A particular problem with using simple parameterizations based on the uncollided flux is that approximations based on spherical geometry might not apply to the more common cylindrical cases used for accelerator shielding. This source of error has been discussed at length by Stevenson and others. To study

  7. Clinicians adopting evidence based guidelines: a case study with thromboprophylaxis

    PubMed Central

    2011-01-01

    Background Venous Thromboembolism (VTE) is a cause of hospital mortality and managing its morbidity is associated with significant expenditure. Uptake of evidenced based guideline recommendations intended to prevent VTE in hospital settings is sub-optimal. This study was conducted to explore clinicians' attitudes and the clinical environment in which they work to understand their reluctance to adopt VTE prophylaxis guidelines. Methods Between February and November 2009, 40 hospital employed doctors from 2 Australian metropolitan hospitals were interviewed in depth. Qualitative data were analysed according to thematic methodology. Results Analysis of interviews revealed that barriers to evidence based practice include i) the fragmented system of care delivery where multiple members of teams and multiple teams are responsible for each patient's care, and in the case of VTE, where everyone shares responsibility and no-one in particular is responsible; ii) the culture of practice where team practice is tailored to that of the team head, and where medicine is considered an 'art' in which guidelines should be adapted to each patient rather than applied universally. Interviewees recommend clear allocation of responsibility and reminders to counteract VTE risk assessment being overlooked. Conclusions Senior clinicians are the key enablers for practice change. They will need to be convinced that guideline compliance adds value to their patient care. Then with the support of systems in the organisation designed to minimize the effects of care fragmentation, they will drive practice changes in their teams. We believe that evidence based practice is only possible with a coordinated program that addresses individual, cultural and organisational constraints. PMID:21951830

  8. Ablation study of tungsten-based nuclear thermal rocket fuel

    NASA Astrophysics Data System (ADS)

    Smith, Tabitha Elizabeth Rose

    The research described in this thesis has been performed in order to support the materials research and development efforts of NASA Marshall Space Flight Center (MSFC), of Tungsten-based Nuclear Thermal Rocket (NTR) fuel. The NTR was developed to a point of flight readiness nearly six decades ago and has been undergoing gradual modification and upgrading since then. Due to the simplicity in design of the NTR, and also in the modernization of the materials fabrication processes of nuclear fuel since the 1960's, the fuel of the NTR has been upgraded continuously. Tungsten-based fuel is of great interest to the NTR community, seeking to determine its advantages over the Carbide-based fuel of the previous NTR programs. The materials development and fabrication process contains failure testing, which is currently being conducted at MSFC in the form of heating the material externally and internally to replicate operation within the nuclear reactor of the NTR, such as with hot gas and RF coils. In order to expand on these efforts, experiments and computational studies of Tungsten and a Tungsten Zirconium Oxide sample provided by NASA have been conducted for this dissertation within a plasma arc-jet, meant to induce ablation on the material. Mathematical analysis was also conducted, for purposes of verifying experiments and making predictions. The computational method utilizes Anisimov's kinetic method of plasma ablation, including a thermal conduction parameter from the Chapman Enskog expansion of the Maxwell Boltzmann equations, and has been modified to include a tangential velocity component. Experimental data matches that of the computational data, in which plasma ablation at an angle shows nearly half the ablation of plasma ablation at no angle. Fuel failure analysis of two NASA samples post-testing was conducted, and suggestions have been made for future materials fabrication processes. These studies, including the computational kinetic model at an angle and the

  9. A Population-based study of dementia in the oldest old: the Monzino 80-plus Study

    PubMed Central

    2011-01-01

    Background Despite being the fastest growing and the most cognitively impaired age group, the oldest olds are under-represented in clinical research. The purpose of this study was to describe the design, methods, and baseline characteristics of the survey population and investigate possible differences in demographic, cognitive, functional, and behavioral characteristics between oldest old with and without any performance on cognitive tests and between oldest old alive and those deceased prior to the interview. Methods The Monzino 80-plus Study is a prospective door-to-door population-based survey among 80 years or older residents in the municipalities in the province of Varese, Italy. Dementia cases were identified with a one-phase design. Trained psychologists interviewed both the subject and a proxy informant. The interview included a comprehensive standardized questionnaire together with an array of rating scales and a multidomain cognitive battery to assess cognitive and functional ability, behavioral disturbances and mood. Results Information was available for 2,139 of the 2,428 registered individuals aged 80 years or older. Main baseline characteristics of the population are reported and discussed. In comparison with those living, elderly persons who had died before the first visit were older, had twice the rate of institutionalization, poorer cognitive performance and competence, and significantly greater instrumental and basic functional disability. The percentage of elderly persons, alive at baseline, without Mini-Mental State Examination rose rather evenly with age. Moreover, they had significantly worse cognitive competence and functional ability, and reported higher prevalences of depressive symptoms and problem behaviors than those with Mini-Mental State Examination. Conclusions Prospective investigation of a large population of oldest old can contribute significantly to understanding the relations between age, cognitive decline, and dementia

  10. Ophthalmic manifestations of tuberous sclerosis: a population based study

    PubMed Central

    Rowley, S; O'Callaghan, F; Osborne, J

    2001-01-01

    BACKGROUND/AIMS—Tuberous sclerosis complex (TSC) has retinal and non-retinal ophthalmic manifestations. This study was designed to determine the prevalence of the ophthalmic manifestations and of refractive errors in a population of patients with TSC.
METHODS—179 patients identified were in a prevalence study of TSC in the south of England and 107 of these agreed to full ophthalmic examination which was successful in 100. Ophthalmic examination included examination of the eyelids, cover test, examination of the irides, dilation funduscopy using both direct and indirect ophthalmoscopy, and refraction using retinoscopy. Myopia was defined as a spherical equivalent <−0.5D and hyperopia as a spherical equivalent >+0.5D.
RESULTS—Retinal hamartomas were seen in 44 of the 100 patients. The commonest morphological type of hamartoma seen was the flat, translucent lesion in 31 of the 44 patients (70%). The multinodular "mulberry" lesion was seen in 24 of the 44 patients (55%) and the transitional type lesion was seen in four of the 44 patients (9%). Punched out areas of retinal depigmentation were seen in 39 of the 100 patients but only six of 100 controls. 27% of eyes were myopic, 22% were hyperopic, and 27% had astigmatism >0.75D. Of the non-retinal findings, 39 patients had angiofibromas of the eyelids, five had non-paralytic strabismus, and three had colobomas.
CONCLUSION—Apart from the higher prevalence of flat retinal hamartomas, the findings of this study compare closely with previous large clinic based series of TSC patients. Refractive findings were similar to previous studies of a similarly aged non-TSC population. This is the first series to document the statistically significant association of punched out chorioretinal depigmentation with TSC and the authors believe that it should be looked for as an aid to diagnosis.

 PMID:11264130

  11. A community-based prospective cohort study of dengue viral infection in Malaysia: the study protocol.

    PubMed

    Jahan, Nowrozy Kamar; Ahmad, Mohtar Pungut; Dhanoa, Amreeta; Meng, Cheong Yuet; Ming, Lau Wee; Reidpath, Daniel D; Allotey, Pascale; Zaini, Anuar; Phipps, Maude Elvira; Fatt, Quek Kia; Rabu, Aman Bin; Sirajudeen, Rowther; Fatan, Ahmad AbdulBasitz Ahmad; Ghafar, Faidzal Adlee; Ahmad, Hamdan Bin; Othman, Iekhsan; SyedHassan, Sharifah

    2016-08-11

    Globally, dengue infections constitute a significant public health burden. In recent decades, Malaysia has become a dengue hyper-endemic country with the co-circulation of the four dengue virus serotypes. The cyclical dominance of sub-types contributes to a pattern of major outbreaks. The consequences can be observed in the rising incidence of reported dengue cases and dengue related deaths. Understanding the complex interaction of the dengue virus, its human hosts and the mosquito vectors at the community level may help develop strategies for addressing the problem. A prospective cohort study will be conducted in Segamat district of Johor State in Peninsular Malaysia. Researchers received approval from the Malaysian Medical Research Ethics Committee and Monash University Human Research Ethics Committee. The study will be conducted at a Malaysian based health and demographic surveillance site over a 1 year period in three different settings (urban, semi-urban and rural). The study will recruit healthy adults (male and female) aged 18 years and over, from three ethnic groups (Malay, Chinese and Indian). The sample size calculated using the Fleiss method with continuity correction is 333. Sero-surveillance of participants will be undertaken to identify asymptomatic, otherwise healthy cases; cases with dengue fever who are managed as out-patients; and cases with dengue fever admitted to a hospital. A genetic analysis of the participants will be undertaken to determine whether there is a relationship between genetic predisposition and disease severity. A detailed medical history, past history of dengue infection, vaccination history against other flaviviruses such as Japanese encephalitis and Yellow fever, and the family history of dengue infection will also be collected. In addition, a mosquito surveillance will be carried out simultaneously in recruitment areas to determine the molecular taxonomy of circulating vectors. The research findings will estimate the burden

  12. Design of a Project-Based Study Environment on the World Wide Web.

    ERIC Educational Resources Information Center

    Grooters, Fiona; de Vries, Sjoerd

    This paper presents the design of a project-based study environment on the World Wide Web based upon the e-study concept, i.e., studying by means of Internet technologies. The first section discusses the e-study concept, including Interactive Study Environments (ISE), Interactive Study Systems, and online Study Services. Design guidelines for a…

  13. RP-1 Thermal Stability and Copper Based Materials Compatibility Study

    NASA Technical Reports Server (NTRS)

    Stiegemeier, B. R.; Meyer, M. L.; Driscoll, E.

    2005-01-01

    A series of electrically heated tube tests was performed at the NASA Glenn Research Center s Heated Tube Facility to investigate the effect that sulfur content, test duration, and tube material play in the overall thermal stability and materials compatibility characteristics of RP-1. Scanning-electron microscopic (SEM) analysis in conjunction with energy dispersive spectroscopy (EDS) were used to characterize the condition of the tube inner wall surface and any carbon deposition or corrosion formed during these runs. Results of the parametric study indicate that tests with standard RP-1 (total sulfur -23 ppm) and pure copper tubing are characterized by a depostion/deposit shedding process producing local wall temperature swings as high as 500 F. The effect of this shedding is to keep total carbon deposition levels relatively constant for run times from 20 minutes up to 5 hours, though increasing tube pressure drops were observed in all runs. Reduction in the total sulfur content of the fuel from 23 ppm to less than 0.1 ppm resulted in the elimination of deposit shedding, local wall temperature variation, and the tube pressure drop increases that were observed in standard sulfur level RP-1 tests. The copper alloy GRCop-84, a copper alloy developed specifically for high heat flux applications, was found to exhibit higher carbon deposition levels compared to identical tests performed in pure copper tubes. Results of the study are consistent with previously published heated tube data which indicates that small changes in fuel total sulfur content can lead to significant differences in the thermal stability of kerosene type fuels and their compatibility with copper based materials. In conjunction with the existing thermal stability database, these findings give insight into the feasibility of cooling a long life, high performance, high-pressure liquid rocket combustor and nozzle with RP-1.

  14. Model Based Systems Engineering on the Europa Mission Concept Study

    NASA Technical Reports Server (NTRS)

    Bayer, Todd J.; Chung, Seung; Cole, Bjorn; Cooke, Brian; Dekens, Frank; Delp, Chris; Gontijo, I.; Lewis, Kari; Moshir, Mehrdad; Rasmussen, Robert; hide

    2012-01-01

    At the start of 2011, the proposed Jupiter Europa Orbiter (JEO) mission was staffing up in expectation of becoming an official project later in the year for a launch in 2020. A unique aspect of the pre-project work was a strong emphasis and investment on the foundations of Model-Based Systems Engineering (MBSE). As so often happens in this business, plans changed: NASA's budget and science priorities were released and together fundamentally changed the course of JEO. As a result, it returned to being a study task whose objective is to propose more affordable ways to accomplish the science. As part of this transition, the question arose as to whether it could continue to afford the investment in MBSE. In short, the MBSE infusion has survived and is providing clear value to the study effort. By leveraging the existing infrastructure and a modest additional investment, striking advances in the capture and analysis of designs using MBSE were achieved. In the process, the need to remain relevant in the new environment has brought about a wave of innovation and progress. The effort has reaffirmed the importance of architecting. It has successfully harnessed the synergistic relationship of architecting to system modeling. We have found that MBSE can provide greater agility than traditional methods. We have also found that a diverse 'ecosystem' of modeling tools and languages (SysML, Mathematica, even Excel) is not only viable, but an important enabler of agility and adaptability. This paper will describe the successful application of MBSE in the dynamic environment of early mission formulation, the significant results produced and lessons learned in the process.

  15. Recurrence of hyperemesis gravidarum across generations: population based cohort study

    PubMed Central

    Skjærven, Rolv; Grjibovski, Andrej M; Gunnes, Nina; Vangen, Siri; Magnus, Per

    2010-01-01

    Objective To estimate the risk of hyperemesis gravidarum (hyperemesis) according to whether the daughters and sons under study were born after pregnancies complicated by hyperemesis. Design Population based cohort study. Setting Registry data from Norway. Participants Linked generational data from the medical birth registry of Norway (1967-2006): 544 087 units of mother and childbearing daughter and 399 777 units of mother and child producing son. Main outcome measure Hyperemesis in daughters in mother and childbearing daughter units and hyperemesis in female partners of sons in mother and child producing son units. Results Daughters who were born after a pregnancy complicated by hyperemesis had a 3% risk of having hyperemesis in their own pregnancy, while women who were born after an unaffected pregnancy had a risk of 1.1% (unadjusted odds ratio 2.9, 95% confidence interval 2.4 to 3.6). Female partners of sons who were born after pregnancies complicated by hyperemesis had a risk of 1.2% (1.0, 0.7 to 1.6). Daughters born after a pregnancy not complicated by hyperemesis had an increased risk of the condition if the mother had hyperemesis in a previous or subsequent pregnancy (3.2 (1.6 to 6.4) if hyperemesis had occurred in one of the mother’s previous pregnancies and 3.7 (1.5 to 9.1) if it had occurred in a later pregnancy). Adjustment for maternal age at childbirth, period of birth, and parity did not change the estimates. Restrictions to firstborns did not influence the results. Conclusions Hyperemesis gravidarum is more strongly influenced by the maternal genotype than the fetal genotype, though environmental influences along the maternal line cannot be excluded as contributing factors. PMID:21030362

  16. Model Based Systems Engineering on the Europa Mission Concept Study

    NASA Technical Reports Server (NTRS)

    Bayer, Todd J.; Chung, Seung; Cole, Bjorn; Cooke, Brian; Dekens, Frank; Delp, Chris; Gontijo, I.; Lewis, Kari; Moshir, Mehrdad; Rasmussen, Robert; Wagner, Dave

    2012-01-01

    At the start of 2011, the proposed Jupiter Europa Orbiter (JEO) mission was staffing up in expectation of becoming an official project later in the year for a launch in 2020. A unique aspect of the pre-project work was a strong emphasis and investment on the foundations of Model-Based Systems Engineering (MBSE). As so often happens in this business, plans changed: NASA's budget and science priorities were released and together fundamentally changed the course of JEO. As a result, it returned to being a study task whose objective is to propose more affordable ways to accomplish the science. As part of this transition, the question arose as to whether it could continue to afford the investment in MBSE. In short, the MBSE infusion has survived and is providing clear value to the study effort. By leveraging the existing infrastructure and a modest additional investment, striking advances in the capture and analysis of designs using MBSE were achieved. In the process, the need to remain relevant in the new environment has brought about a wave of innovation and progress. The effort has reaffirmed the importance of architecting. It has successfully harnessed the synergistic relationship of architecting to system modeling. We have found that MBSE can provide greater agility than traditional methods. We have also found that a diverse 'ecosystem' of modeling tools and languages (SysML, Mathematica, even Excel) is not only viable, but an important enabler of agility and adaptability. This paper will describe the successful application of MBSE in the dynamic environment of early mission formulation, the significant results produced and lessons learned in the process.

  17. The first large population based twin study of coeliac disease

    PubMed Central

    Greco, L; Romino, R; Coto, I; Di Cosmo, N; Percopo, S; Maglio, M; Paparo, F; Gasperi, V; Limongelli, M G; Cotichini, R; D'Agate, C; Tinto, N; Sacchetti, L; Tosi, R; Stazi, M A

    2002-01-01

    Background and aims: The genetic load in coeliac disease has hitherto been inferred from case series or anecdotally referred twin pairs. We have evaluated the genetic component in coeliac disease by estimating the concordance rate for the disease among twin pairs in a large population based study. Methods: The Italian Twin Registry was matched with the membership lists of a patient support group. Forty seven twin pairs were recruited and screened for antiendomysial (EMA) and antihuman-tissue transglutaminase (anti-tTG) antibodies; zygosity was verified by DNA fingerprinting and twins were typed for HLA class II DRB1 and DQB1 molecules. Results: Concordance rates for coeliac disease differ significantly between monozygotic (MZ) (0.86 probandwise and 0.75 pairwise) and dizygotic (DZ) (0.20 probandwise and 0.11 pairwise) twins. This is the highest concordance so far reported for a multifactorial disease. A logistic regression model, adjusted for age, sex, number of shared HLA haplotypes, and zygosity, showed that genotypes DQA1*0501/DQB1*0201 and DQA1*0301/DQB1*0302 (encoding for heterodimers DQ2 and DQ8, respectively) conferred to the non-index twin a risk of contracting the disease of 3.3 and 1.4, respectively. The risk of being concordant for coeliac disease estimated for the non-index twin of MZ pairs was 17 (95% confidence interval 2.1–134), independent of the DQ at risk genotype. Conclusion: This study provides substantial evidence for a very strong genetic component in coeliac disease, which is only partially due to the HLA region. PMID:11950806

  18. Technology base studies of long-term MCFC performance

    SciTech Connect

    Selman, J.R.; Yazici, M.S.

    1995-12-01

    Cathode dissolution into the electrolyte matrix and endurance of current collector/separator plate materials are the main life-limiting factors of the state-of-the art MCFC. These components are also major contributors to the total system cost. Therefore, to reduce capital cost, it is necessary to minimize hardware corrosion and increase cell life. This study consists of experimental evaluation of corrosion processes with the objective to further practical; understanding of corrosion behavior of alloys and alloy components under cathodic gas conditions. Nickel, iron, cobalt and stainless steels 310 and 316L are analyzed. The experimental study consists of: (1) Observation of open circuit potential (OCP) changes. Surface reactions occurring without net passage of current are proposed based on this measurement. (2) Applying cyclic voltammetry, which provides information about the possible electrode reactions at different stages of polarization. (3) Applying AC impedance to support the result of tasks 1 and 2 at different stages of oxidation, and data analysis by means of equivalent circuits. Open circuit conditions as well as positive and negative polarization are used in the impedance measurements. (4) Surface analysis of the electrodes by SEM-EDX and X-ray diffraction. To obtain more information from electrochemical measurements a novel approach has been applied in cell design. In this two electrode approach, one electrode is fully immersed, and the other is wetted by carbonate melt via an alumina tube which has a thin film on it. While camera observation of these two different electrode conditions will identify the effect of carbonate wetting on the state of the surface, electrochemical measurements enable a quantitative comparison between complete submersion and wetting by a film of carbonate.

  19. Ethnobotanical perspective of antimalarial plants: traditional knowledge based study.

    PubMed

    Qayum, Abdul; Arya, Rakesh; Lynn, Andrew M

    2016-02-04

    Considering the demand of antimalarial plants it has become essential to find and locate them for their optimal extraction. The work aims to find plants with antimalarial activities which were used by the local people; to raise the value of traditional knowledge system (TKS) prevalent in the study region; to compile characteristics of local plants used in malaria treatment (referred as antimalarial plants) and to have its spatial distribution analysis to establish a concept of geographical health. Antimalarial plants are listed based on literature survey and field data collected during rainy season, from 85 respondents comprised of different ethnic groups. Ethno-medicinal utilities of plants was extracted; botanical name, family, local name, part used, folklore, geographical location and image of plants were recorded after cross validating with existing literatures. The interview was trifurcated in field, Vaidya/Hakims and house to house. Graphical analysis was done for major plants families, plant part used, response of people and patients and folklore. Mathematical analysis was done for interviewee's response, methods of plant identification and people's preferences of TKS through three plant indices. Fifty-one plants belonging to 27 families were reported with its geographical attributes. It is found plant root (31.75 %) is used mostly for malaria treatment and administration mode is decoction (41.2 %) mainly. The study area has dominance of plants of family Fabaceae (7), Asteraceae (4), Acanthaceae (4) and Amaranthaceae (4). Most popular plants found are Adhatoda vasica, Cassia fistula and Swertia chirata while  % usage of TKS is 82.0 % for malaria cure. The research findings can be used by both scientific community and common rural people for bio-discovery of these natural resources sustainably. The former can extract the tables to obtain a suitable plant towards finding a suitable lead molecule in a drug discovery project; while the latter can meet their

  20. Technology base studies of long-term MCFC performance

    SciTech Connect

    Selman, J.R.

    1995-08-01

    Cathode dissolution into the electrolyte matrix and endurance of current collector/separator plate materials are the main life-limiting factors of the state-of-the art MCFC. These components are also major contributors to the total system cost. Therefore, to reduce capital cost, it is necessary to minimize hardware corrosion and increase cell life. This study consists of experimental evaluation of corrosion processes with the objective to further practical; understanding of corrosion behavior of alloys and alloy components under cathodic gas conditions. Nickel, iron, cobalt and stainless steels 310 and 316L are analyzed. The experimental study consists of (1) Observation of open circuit potential (OCP) changes. Surface reactions occurring without net passage of current are proposed based on this measurement. (2) Applying cyclic voltammetry, which provides information about the possible electrode reactions at different stages of polarization. (3) Applying AC impedance to support the result of tasks 1 and 2 at different stages of oxidation, and data analysis by means of equivalent circuits. Open circuit conditions as well as positive and negative polarization are used in the impedance measurements. (4) Surface analysis of the electrodes by SEM-EDX and X-ray diffraction. To obtain more information from electrochemical measurements a novel approach has been applied in cell design. In this two-electrode approach, one electrode is fully immersed, and the other is wetted by carbonate melt via an alumina tube which has a thin film on it. While camera observation of these two different electrode conditions will identify the effect of carbonate wetting on the state of the surface, electrochemical measurements enable a quantitative comparison between complete submersion and wetting by a film of carbonate.

  1. Estimating glomerular filtration rate in a population-based study

    PubMed Central

    Shankar, Anoop; Lee, Kristine E; Klein, Barbara EK; Muntner, Paul; Brazy, Peter C; Cruickshanks, Karen J; Nieto, F Javier; Danforth, Lorraine G; Schubert, Carla R; Tsai, Michael Y; Klein, Ronald

    2010-01-01

    Background: Glomerular filtration rate (GFR)-estimating equations are used to determine the prevalence of chronic kidney disease (CKD) in population-based studies. However, it has been suggested that since the commonly used GFR equations were originally developed from samples of patients with CKD, they underestimate GFR in healthy populations. Few studies have made side-by-side comparisons of the effect of various estimating equations on the prevalence estimates of CKD in a general population sample. Patients and methods: We examined a population-based sample comprising adults from Wisconsin (age, 43–86 years; 56% women). We compared the prevalence of CKD, defined as a GFR of <60 mL/min per 1.73 m2 estimated from serum creatinine, by applying various commonly used equations including the modification of diet in renal disease (MDRD) equation, Cockcroft–Gault (CG) equation, and the Mayo equation. We compared the performance of these equations against the CKD definition of cystatin C >1.23 mg/L. Results: We found that the prevalence of CKD varied widely among different GFR equations. Although the prevalence of CKD was 17.2% with the MDRD equation and 16.5% with the CG equation, it was only 4.8% with the Mayo equation. Only 24% of those identified to have GFR in the range of 50–59 mL/min per 1.73 m2 by the MDRD equation had cystatin C levels >1.23 mg/L; their mean cystatin C level was only 1 mg/L (interquartile range, 0.9–1.2 mg/L). This finding was similar for the CG equation. For the Mayo equation, 62.8% of those patients with GFR in the range of 50–59 mL/min per 1.73 m2 had cystatin C levels >1.23 mg/L; their mean cystatin C level was 1.3 mg/L (interquartile range, 1.2–1.5 mg/L). The MDRD and CG equations showed a false-positive rate of >10%. Discussion: We found that the MDRD and CG equations, the current standard to estimate GFR, appeared to overestimate the prevalence of CKD in a general population sample. PMID:20730018

  2. Biosensors for EVA: Improved Instrumentation for Ground-based Studies

    NASA Technical Reports Server (NTRS)

    Soller, B.; Ellerby, G.; Zou, F.; Scott, P.; Jin, C.; Lee, S. M. C.; Coates, J.

    2010-01-01

    During lunar excursions in the EVA suit, real-time measurement of metabolic rate is required to manage consumables and guide activities to ensure safe return to the base. Metabolic rate, or oxygen consumption (VO2), is normally measured from pulmonary parameters but cannot be determined with standard techniques in the oxygen-rich environment of a spacesuit. Our group has developed novel near infrared spectroscopic (NIRS) methods to calculate muscle oxygen saturation (SmO 2), hematocrit, and pH, and we recently demonstrated that we can use our NIRS sensor to measure VO 2 on the leg during cycling. Our NSBRI project has 4 objectives: (1) increase the accuracy of the metabolic rate calculation through improved prediction of stroke volume; (2) investigate the relative contributions of calf and thigh oxygen consumption to metabolic rate calculation for walking and running; (3) demonstrate that the NIRS-based noninvasive metabolic rate methodology is sensitive enough to detect decrement in VO 2 in a space analog; and (4) improve instrumentation to allow testing within a spacesuit. Over the past year we have made progress on all four objectives, but the most significant progress was made in improving the instrumentation. The NIRS system currently in use at JSC is based on fiber optics technology. Optical fiber bundles are used to deliver light from a light source in the monitor to the patient, and light reflected back from the patient s muscle to the monitor for spectroscopic analysis. The fiber optic cables are large and fragile, and there is no way to get them in and out of the test spacesuit used for ground-based studies. With complimentary funding from the US Army, we undertook a complete redesign of the sensor and control electronics to build a novel system small enough to be used within the spacesuit and portable enough to be used by a combat medic. In the new system the filament lamp used in the fiber optic system was replaced with a novel broadband near infrared

  3. Biosensors for EVA: Improved Instrumentation for Ground-based Studies

    NASA Technical Reports Server (NTRS)

    Soller, B.; Ellerby, G.; Zou, F.; Scott, P.; Jin, C.; Lee, S. M. C.; Coates, J.

    2010-01-01

    During lunar excursions in the EVA suit, real-time measurement of metabolic rate is required to manage consumables and guide activities to ensure safe return to the base. Metabolic rate, or oxygen consumption (VO2), is normally measured from pulmonary parameters but cannot be determined with standard techniques in the oxygen-rich environment of a spacesuit. Our group has developed novel near infrared spectroscopic (NIRS) methods to calculate muscle oxygen saturation (SmO 2), hematocrit, and pH, and we recently demonstrated that we can use our NIRS sensor to measure VO 2 on the leg during cycling. Our NSBRI project has 4 objectives: (1) increase the accuracy of the metabolic rate calculation through improved prediction of stroke volume; (2) investigate the relative contributions of calf and thigh oxygen consumption to metabolic rate calculation for walking and running; (3) demonstrate that the NIRS-based noninvasive metabolic rate methodology is sensitive enough to detect decrement in VO 2 in a space analog; and (4) improve instrumentation to allow testing within a spacesuit. Over the past year we have made progress on all four objectives, but the most significant progress was made in improving the instrumentation. The NIRS system currently in use at JSC is based on fiber optics technology. Optical fiber bundles are used to deliver light from a light source in the monitor to the patient, and light reflected back from the patient s muscle to the monitor for spectroscopic analysis. The fiber optic cables are large and fragile, and there is no way to get them in and out of the test spacesuit used for ground-based studies. With complimentary funding from the US Army, we undertook a complete redesign of the sensor and control electronics to build a novel system small enough to be used within the spacesuit and portable enough to be used by a combat medic. In the new system the filament lamp used in the fiber optic system was replaced with a novel broadband near infrared

  4. Study on stimulus-responsive cellulose-based polymeric materials

    NASA Astrophysics Data System (ADS)

    Luo, Hongsheng

    Stimulus-responsive cellulose-based polymeric materials were developed by physical and chemical approaches. The thermal, structural, mechanical and morphological properties of the samples were comprehensively investigated by multiple tools. Shape memory effect (SME), programming-structure-property relationship and underling mechanisms were emphasized in this study. Some new concepts, such as heterogeneous-twin-switch, path-dependent multi-shape, rapidly switchable water-sensitive SME were established. The samples were divided into two categories. For the first category, cellulose nano-whiskers (CNWs) were incorporated into crystalline shape memory polyurethane (SMPU) and thermal plastic polyurethane (TPU). The CNW-SMPU nano-composites had heterogeneous switches. Triple- and multi-shape effects were achieved for the CNW-SMPU nano-composites by applying into appropriate thermal-aqueous-mechanical programming. Furthermore, the thermally triggered shape recovery of the composites was found to be tuneable, depending on the PCN content. Theoretical prediction along with numerical analysis was conducted, providing evidence on the possible microstructure of the CNW-SMPU nano-composites. Rapidly switchable water-sensitive SME of the CNW-TPU nano-composites was unprecedentedly studied, which originated from the reversible regulation of hydrogen bonding by water. The samples in the second category consisted of cellulose-polyurethane (PU) blends, cellulose-poly(acrylic acid) (PAA) composites and modified cellulose with supramolecular switches, featuring the requirement of homogeneous cellulose solution in the synthesis process. The reversible behaviours of the cellulose-PU blends in wet-dry cycles as well as the underlying shape memory mechanism were characterized and disclosed. The micro-patterns of the blends were found to be self-similar in fractal dimensions. Cellulose-PAA semi-interpenetrating networks exhibited mechanical adaptability in wet-dry cycles. A type of

  5. Cyberbullying among Finnish adolescents – a population-based study

    PubMed Central

    2012-01-01

    Background Cyberbullying, threatening or harassing another via the internet or mobile phones, does not cause physically harm and thus the consequences are less visible. Little research has been performed on the occurrence of cyberbullying among adolescents or the perception of its seriousness. Only a few population-based studies have been published, none of which included research on the witnessing of cyberbullying. Here, we examined exposure to cyberbullying during the last year, and its frequency and perceived seriousness among 12 to 18-year-old adolescents in Finland. We studied four dimensions of cyberbullying: being a victim, bully, or both victim and bully of cyberbullying, and witnessing the cyberbullying of friends. Methods Self-administered questionnaires, including four questions on cyberbullying, were mailed to a representative sample of 12-, 14-, 16-, and 18-year-old Finns in 2009 (the Adolescent Health and Lifestyle Survey). The respondents could answer via the internet or paper questionnaire. Results The number of respondents was 5516 and the response rate was 56%. Girls more often than boys reported experiencing at least one dimension of cyberbullying during the last year. The proportion was highest among 14-year-olds and lowest among 18-year-olds of both sexes. Among girls, the most commonly encountered dimension was witnessing the cyberbullying of friends (16%); and being a victim was slightly more common than being a bully (11% vs. 9%). Among boys, an equal proportion, approximately 10%, had been a victim, a bully, or had witnessed cyberbullying. The proportion of bully-victims was 4%. Serious and disruptive cyberbullying was experienced by 2% of respondents and weekly cyberbullying by 1%; only 0.5% of respondents had been bullied weekly and considered bullying serious and disruptive. Conclusions Adolescents are commonly exposed to cyberbullying, but it is rarely frequent or considered serious or disruptive. Cyberbullying exposure differed between

  6. Sexuality after a cancer diagnosis: A population-based study.

    PubMed

    Jackson, Sarah E; Wardle, Jane; Steptoe, Andrew; Fisher, Abigail

    2016-12-15

    This study explored differences in sexual activity, function, and concerns between cancer survivors and cancer-free controls in a population-based study. The data were from 2982 men and 3708 women who were 50 years old or older and were participating in the English Longitudinal Study of Ageing. Sexual well-being was assessed with the Sexual Relationships and Activities Questionnaire, and cancer diagnoses were self-reported. There were no differences between cancer survivors and controls in levels of sexual activity (76.0% vs 78.5% for men and 58.2% vs 55.5% for women) or sexual function. Men and women with cancer diagnoses were more dissatisfied with their sex lives than controls (age-adjusted percentages: 30.9% vs 19.8% for men [P = .023] and 18.2% vs 11.8% for women [P = .034]), and women with cancer were more concerned about levels of sexual desire (10.2% vs 7.1%; P = .006). Women diagnosed < 5 years ago were more likely to report difficulty with becoming aroused (55.4% vs 31.8%; P = .016) and achieving orgasm (60.6% vs 28.3%; P < .001) and were more concerned about sexual desire (14.8% vs 7.1%; P = .007) and orgasmic experience (17.6% vs 7.1%; P = .042) than controls, but there were no differences in men. Self-reports of sexual activity and functioning in older people with cancer are broadly comparable to age-matched, cancer-free controls. There is a need to identify the causes of sexual dissatisfaction among long-term cancer survivors despite apparently normal levels of sexual activity and function for their age. The development of interventions addressing low sexual desire and problems with sexual functioning in women is also important and may be particularly relevant for cancer survivors after treatment. Cancer 2016;122:3883-3891. © 2016 American Cancer Society. © 2016 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.

  7. A Comprehensive Family-Based Replication Study of Schizophrenia Genes

    PubMed Central

    Aberg, Karolina A.; Liu, Youfang; Bukszár, Jozsef; McClay, Joseph L.; Khachane, Amit N.; Andreassen, Ole A.; Blackwood, Douglas; Corvin, Aiden; Djurovic, Srdjan; Gurling, Hugh; Ophoff, Roel; Pato, Carlos N.; Pato, Michele T.; Riley, Brien; Webb, Todd; Kendler, Kenneth; O’Donovan, Mick; Craddock, Nick; Kirov, George; Owen, Mike; Rujescu, Dan; St Clair, David; Werge, Thomas; Hultman, Christina M.; Delisi, Lynn E.; Sullivan, Patrick; van den Oord, Edwin J.

    2017-01-01

    Importance Schizophrenia (SCZ) is a devastating psychiatric condition. Identifying the specific genetic variants and pathways that increase susceptibility to SCZ is critical to improve disease understanding and address the urgent need for new drug targets. Objective To identify SCZ susceptibility genes. Design We integrated results from a meta-analysis of 18 genome-wide association studies (GWAS) involving 1 085 772 single-nucleotide polymorphisms (SNPs) and 6 databases that showed significant informativeness for SCZ. The 9380 most promising SNPs were then specifically genotyped in an independent family-based replication study that, after quality control, consisted of 8107 SNPs. Setting Linkage meta-analysis, brain transcriptome meta-analysis, candidate gene database, OMIM, relevant mouse studies, and expression quantitative trait locus databases. Patients We included 11 185 cases and 10 768 control subjects from 6 databases and, after quality control 6298 individuals (including 3286 cases) from 1811 nuclear families. Main Outcomes and Measures Case-control status for SCZ. Results Replication results showed a highly significant enrichment of SNPs with small P values. Of the SNPs with replication values of P<.01, the proportion of SNPs that had the same direction of effects as in the GWAS meta-analysis was 89% in the combined ancestry group (sign test, P<2.20×10−16) and 93% in subjects of European ancestry only (P<2.20×10−16). Our results supported the major histocompatibility complex region showing a 3.7-fold overall enrichment of replication values of P<.01 in subjects from European ancestry. We replicated SNPs in TCF4 (P=2.53×10−10) and NOTCH4 (P=3.16×10−7) that are among the most robust SCZ findings. More novel findings included POM121L2 (P=3.51×10−7), AS3MT (P=9.01×10−7), CNNM2 (P=6.07×10−7), and NT5C2 (P=4.09×10−7). To explore the many small effects, we performed pathway analyses. The most significant pathways involved neuronal function

  8. Cyberbullying among Finnish adolescents--a population-based study.

    PubMed

    Lindfors, Pirjo L; Kaltiala-Heino, Riittakerttu; Rimpelä, Arja H

    2012-11-23

    Cyberbullying, threatening or harassing another via the internet or mobile phones, does not cause physically harm and thus the consequences are less visible. Little research has been performed on the occurrence of cyberbullying among adolescents or the perception of its seriousness. Only a few population-based studies have been published, none of which included research on the witnessing of cyberbullying. Here, we examined exposure to cyberbullying during the last year, and its frequency and perceived seriousness among 12 to 18-year-old adolescents in Finland. We studied four dimensions of cyberbullying: being a victim, bully, or both victim and bully of cyberbullying, and witnessing the cyberbullying of friends. Self-administered questionnaires, including four questions on cyberbullying, were mailed to a representative sample of 12-, 14-, 16-, and 18-year-old Finns in 2009 (the Adolescent Health and Lifestyle Survey). The respondents could answer via the internet or paper questionnaire. The number of respondents was 5516 and the response rate was 56%. Girls more often than boys reported experiencing at least one dimension of cyberbullying during the last year. The proportion was highest among 14-year-olds and lowest among 18-year-olds of both sexes. Among girls, the most commonly encountered dimension was witnessing the cyberbullying of friends (16%); and being a victim was slightly more common than being a bully (11% vs. 9%). Among boys, an equal proportion, approximately 10%, had been a victim, a bully, or had witnessed cyberbullying. The proportion of bully-victims was 4%. Serious and disruptive cyberbullying was experienced by 2% of respondents and weekly cyberbullying by 1%; only 0.5% of respondents had been bullied weekly and considered bullying serious and disruptive. Adolescents are commonly exposed to cyberbullying, but it is rarely frequent or considered serious or disruptive. Cyberbullying exposure differed between sexes, such that girls more often than

  9. Sexuality after a cancer diagnosis: A population‐based study

    PubMed Central

    Wardle, Jane; Steptoe, Andrew; Fisher, Abigail

    2016-01-01

    BACKGROUND This study explored differences in sexual activity, function, and concerns between cancer survivors and cancer‐free controls in a population‐based study. METHODS The data were from 2982 men and 3708 women who were 50 years old or older and were participating in the English Longitudinal Study of Ageing. Sexual well‐being was assessed with the Sexual Relationships and Activities Questionnaire, and cancer diagnoses were self‐reported. RESULTS There were no differences between cancer survivors and controls in levels of sexual activity (76.0% vs 78.5% for men and 58.2% vs 55.5% for women) or sexual function. Men and women with cancer diagnoses were more dissatisfied with their sex lives than controls (age‐adjusted percentages: 30.9% vs 19.8% for men [P = .023] and 18.2% vs 11.8% for women [P = .034]), and women with cancer were more concerned about levels of sexual desire (10.2% vs 7.1%; P = .006). Women diagnosed < 5 years ago were more likely to report difficulty with becoming aroused (55.4% vs 31.8%; P = .016) and achieving orgasm (60.6% vs 28.3%; P < .001) and were more concerned about sexual desire (14.8% vs 7.1%; P = .007) and orgasmic experience (17.6% vs 7.1%; P = .042) than controls, but there were no differences in men. CONCLUSIONS Self‐reports of sexual activity and functioning in older people with cancer are broadly comparable to age‐matched, cancer‐free controls. There is a need to identify the causes of sexual dissatisfaction among long‐term cancer survivors despite apparently normal levels of sexual activity and function for their age. The development of interventions addressing low sexual desire and problems with sexual functioning in women is also important and may be particularly relevant for cancer survivors after treatment. Cancer 2016;122:3883–3891. © 2016 American Cancer Society. PMID:27531631

  10. Older adults with acquired brain injury: a population based study

    PubMed Central

    2013-01-01

    Background Acquired brain injury (ABI), which includes traumatic (TBI) and non-traumatic brain injury (nTBI), is a leading cause of death and disability worldwide. The objective of this study was to examine the trends, characteristics, cause of brain injury, and discharge destination of hospitalized older adults aged 65 years and older with an ABI diagnosis in a population with universal access to hospital care. The profile of characteristics of patients with TBI and nTBI causes of injury was also compared. Methods A population based retrospective cohort study design with healthcare administrative databases was used. Data on acute care admissions were obtained from the Discharge Abstract Database and patients were identified using the International Classification of Diseases – Version 10 codes for Ontario, Canada from April 1, 2003 to March 31, 2010. Older adults were examined in three age groups – 65 to 74, 75 to 84, and 85+ years. Results From 2003/04 to 2009/10, there were 14,518 episodes of acute care associated with a TBI code and 51, 233 episodes with a nTBI code. Overall, the rate of hospitalized TBI and nTBI episodes increased with older age groups. From 2007/08 to 2009/10, the percentage of patients that stayed in acute care for 12 days or more and the percentage of patients with delayed discharge from acute care increased with age. The most common cause of TBI was falls while the most common type of nTBI was brain tumours. The percentage of patients discharged to long term care and complex continuing care increased with age and the percentage discharged home decreased with age. In-hospital mortality also increased with age. Older adults with TBI and nTBI differed significantly in demographic and clinical characteristics and discharge destination from acute care. Conclusions This study showed an increased rate of acute care admissions for both TBI and nTBI with age. It also provided additional support for falls prevention strategies to prevent injury

  11. [Studies on bond strength and hardness of base materials].

    PubMed

    Suga, T; Chiba, E; Shinya, A; Yokozuka, S

    1989-04-01

    Since base materials are used in the construction of abutment teeth and the cavity walls of the teeth with healthy pulp, they need considerable bonding and mechanical strength depending on the site of application. In the present study we examined bonding strength, Martens-Mayer hardness and Vickers hardness of base materials in comparison with natural dentin in order to reevaluate them in terms of prosthetic materials and to provide assessment criteria for their application to prosthetic treatment. The results were as follows: 1) The bonding test showed the lowest value (4.6kgf/cm2) in calcium hydroxide FR (HFR) and the highest (47.9kgf/cm2) in HY-Bond polycarboxylate cement (CHC), a type of polycarboxylate cement. 2) In the test of bonding strength with various types of cement, calcium hydroxide preparations and zinc phosphate cement showed low values (4.6-23.5kgf/cm2) while polycarboxylate cement and glass-ionomer cement showed relatively high values (17.8-40.5kgf/cm2). 3) The Martens-Mayer hardness test showed the highest value (10.82 x 10(4] in dentin cement (GDE) and the lowest (1.09 x 10(4] in propack (EPR). 4) The Vickers hardness test showed the highest value (82) in neo-protect cement (ZPR) and the lowest (1) in propack (EPR). 5) In both Martens-Mayer and Vickers hardness tests with various types of cement, zinc phosphate cement and glass- ionomer cement showed high values, while low values were obtained in calcium hydroxide preparations and zinc-oxide eugenol cement. 6) Zinc phosphate cement and glass-ionomer cement showed no statistically significant differences from natural dentin in either Martens-Mayer hardness or Vickers hardness.

  12. Tracheostomy following severe ischemic stroke: a population based study

    PubMed Central

    Walcott, Brian P.; Kamel, Hooman; Castro, Brandyn; Kimberly, W. Taylor; Sheth, Kevin N.

    2013-01-01

    Goal Stroke can result in varying degrees of respiratory failure. Some patients require tracheostomy in order to facilitate weaning from mechanical ventilation, long-term airway protection, or a combination of the two. Little is known about the rate and predictors of this outcome in patients with severe stroke. We aim to determine the rate of tracheostomy after severe ischemic stroke. Materials & Methods Using the Nationwide Inpatient Sample database from 2007–2009, patients hospitalized with ischemic stroke were identified based on validated International Classification of Diseases, 9th Revision, Clinical Modification codes. Next, patients with stroke were stratified based on whether they were treated with or without decompressive craniectomy, and the rate of tracheostomy for each group was determined. A logistic regression analysis was used to identify predictors of tracheostomy after decompressive craniectomy. Survey weights were used to obtain nationally representative estimates. Findings In 1,550,000 patients discharged with ischemic stroke nationwide, the rate of tracheostomy was 1.3% (95% CI, 1.2–1.4%), with a 1.3% (95% CI, 1.1–1.4%) rate in patients without decompressive craniectomy and a 33% (95% CI, 26–39%) rate in the surgical-treatment group. Logistic regression analysis identified pneumonia as being significantly associated with tracheostomy after decompressive craniectomy (OR 3.95; 95% CI 1.95–6.91). Conclusion Tracheostomy is common following decompressive craniectomy and is strongly associated with the development of pneumonia. Given its impact on patient function and potentially modifiable associated factors, tracheostomy may warrant further study as an important patient-centered outcome among patients with stroke. PMID:24103666

  13. Tracheostomy after severe ischemic stroke: a population-based study.

    PubMed

    Walcott, Brian P; Kamel, Hooman; Castro, Brandyn; Kimberly, W Taylor; Sheth, Kevin N

    2014-01-01

    Stroke can result in varying degrees of respiratory failure. Some patients require tracheostomy in order to facilitate weaning from mechanical ventilation, long-term airway protection, or a combination of the two. Little is known about the rate and predictors of this outcome in patients with severe stroke. We aim to determine the rate of tracheostomy after severe ischemic stroke. Using the Nationwide Inpatient Sample database from 2007 to 2009, patients hospitalized with ischemic stroke were identified based on validated International Classification of Diseases, 9th revision, Clinical Modification codes. Next, patients with stroke were stratified based on whether they were treated with or without decompressive craniectomy, and the rate of tracheostomy for each group was determined. A logistic regression analysis was used to identify predictors of tracheostomy after decompressive craniectomy. Survey weights were used to obtain nationally representative estimates. In 1,550,000 patients discharged with ischemic stroke nationwide, the rate of tracheostomy was 1.3% (95% confidence interval [CI], 1.2-1.4%), with a 1.3% (95% CI, 1.1-1.4%) rate in patients without decompressive craniectomy and a 33% (95% CI, 26-39%) rate in the surgical treatment group. Logistic regression analysis identified pneumonia as being significantly associated with tracheostomy after decompressive craniectomy (odds ratio, 3.95; 95% CI, 1.95-6.91). Tracheostomy is common after decompressive craniectomy and is strongly associated with the development of pneumonia. Given its impact on patient function and potentially modifiable associated factors, tracheostomy may warrant further study as an important patient-centered outcome among patients with stroke. Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  14. Study of cell secretion using MEMS-based arrays

    NASA Astrophysics Data System (ADS)

    Feng, Xiaojun; Szaro, Ben G.; Castracane, James

    2004-01-01

    This paper focuses on the development of a custom MEMS-based array which will facilitate cell secretion studies by enabling parallel electrochemical detection of secretion events from separate cells with millisecond resolution. Initial prototypes of the microarrays have been fabricated with well-shaped gold electrodes which roughly conform to the shape of a single cell. Amperometric measurements on bovine adrenal chromaffin cells using the prototype microarrays concluded that 80% of the catecholamine secreted from the cells was captured by the well-electrodes. This was a 4-fold increase in detection efficiency over the conventional carbon fiber electrode method. To expand the applicability of this method, additional cell-lines and microarray designs are under investigation. An amphibian fibroblast cell-line (FT cell-line, American Tissue Culture Collection) is being used in our lab. FT cells can take up hormones or other biological compounds from the culture media through a non-specific uptake mechanism which is still under investigation. Microarrays of a new design have been fabricated with patterned gold electrodes on polyimide. A different testing method will be applied to these new microarrays. The FT cells will be cultured directly on top of the microarrays to cover the gold electrodes. Cells will then be loaded with norepinephrine by incubation in media containing 1mM norepinephrine. Rapid elevation of intracellular Ca2+ levels triggers the exocytosis of norepinephrine which then can be detected by the gold electrode. The new polyimide based microarrays have been successfully used to support confluent growth of the FT cells. Loading of the FT cells with norepinephrine and electrochemical detection tests are underway.

  15. Study of cell secretion using MEMS-based arrays

    NASA Astrophysics Data System (ADS)

    Feng, Xiaojun; Szaro, Ben G.; Castracane, James

    2003-12-01

    This paper focuses on the development of a custom MEMS-based array which will facilitate cell secretion studies by enabling parallel electrochemical detection of secretion events from separate cells with millisecond resolution. Initial prototypes of the microarrays have been fabricated with well-shaped gold electrodes which roughly conform to the shape of a single cell. Amperometric measurements on bovine adrenal chromaffin cells using the prototype microarrays concluded that 80% of the catecholamine secreted from the cells was captured by the well-electrodes. This was a 4-fold increase in detection efficiency over the conventional carbon fiber electrode method. To expand the applicability of this method, additional cell-lines and microarray designs are under investigation. An amphibian fibroblast cell-line (FT cell-line, American Tissue Culture Collection) is being used in our lab. FT cells can take up hormones or other biological compounds from the culture media through a non-specific uptake mechanism which is still under investigation. Microarrays of a new design have been fabricated with patterned gold electrodes on polyimide. A different testing method will be applied to these new microarrays. The FT cells will be cultured directly on top of the microarrays to cover the gold electrodes. Cells will then be loaded with norepinephrine by incubation in media containing 1mM norepinephrine. Rapid elevation of intracellular Ca2+ levels triggers the exocytosis of norepinephrine which then can be detected by the gold electrode. The new polyimide based microarrays have been successfully used to support confluent growth of the FT cells. Loading of the FT cells with norepinephrine and electrochemical detection tests are underway.

  16. On Combining Family–based and Population-based Case-control Data in Association Studies

    PubMed Central

    Zheng, Yingye; Heagerty, Patrick J.; Hsu, Li; Newcomb, Polly A

    2011-01-01

    Summary Combining data collected from different sources can potentially enhance statistical efficiency in estimating effects of environmental or genetic factors or gene-environment interactions. However, combining data across studies becomes complicated when data are collected under different study designs, such as family-based and unrelated individual-based case-control design. In this paper, we describe likelihood based approaches that permit the joint estimation of covariate effects on disease risk under study designs that include cases, relatives of cases, and unrelated individuals. Our methods accommodate familial residual correlation and a variety of ascertainment schemes. Extensive simulation experiments demonstrate that the proposed methods for estimation and inference perform well in realistic settings. Efficiencies of different designs are contrasted in the simulation. We applied the methods to data from the Colorectal Cancer Family Registry. PMID:20163402

  17. Project Based Learning for Life Skill Building in 12th Grade Social Studies Classrooms: A Case Study

    ERIC Educational Resources Information Center

    Zimmerman, Daniele C.

    2010-01-01

    Based on the assumption that project based learning (PBL) in 12th grade social studies classrooms contributes to the development of life skills for high school seniors in this advanced and globalized time, this research will investigate student experiences with PBL methods for helping them acquire skills along with a case study of a successful PBL…

  18. Videogames, Tools for Change: A Study Based on Activity Theory

    ERIC Educational Resources Information Center

    Méndez, Laura; Lacasa, Pilar

    2015-01-01

    Introduction: The purpose of this study is to provide a framework for analysis from which to interpret the transformations that take place, as perceived by the participants, when commercial video games are used in the classroom. We will show how Activity Theory (AT) is able to explain and interpret these changes. Method: Case studies are…

  19. Cortical Bases of Speech Perception: Evidence from Functional Lesion Studies

    ERIC Educational Resources Information Center

    Boatman, Dana

    2004-01-01

    Functional lesion studies have yielded new information about the cortical organization of speech perception in the human brain. We will review a number of recent findings, focusing on studies of speech perception that use the techniques of electrocortical mapping by cortical stimulation and hemispheric anesthetization by intracarotid amobarbital.…

  20. Studying the Multilingual City: A GIS-Based Approach

    ERIC Educational Resources Information Center

    Veselinova, Ljuba Nikolova; Booza, J. C.

    2009-01-01

    Work in two distinct disciplines, urban geography and sociolinguistics, readily points out the multiethnic and multilingual character of metropolitan areas. However, there is still demand for studies which establish the language structure of modern cities. For the purposes of this pilot study, we focus on the Detroit Metropolitan Area (DMA),…

  1. Videogames, Tools for Change: A Study Based on Activity Theory

    ERIC Educational Resources Information Center

    Méndez, Laura; Lacasa, Pilar

    2015-01-01

    Introduction: The purpose of this study is to provide a framework for analysis from which to interpret the transformations that take place, as perceived by the participants, when commercial video games are used in the classroom. We will show how Activity Theory (AT) is able to explain and interpret these changes. Method: Case studies are…

  2. Cortical Bases of Speech Perception: Evidence from Functional Lesion Studies

    ERIC Educational Resources Information Center

    Boatman, Dana

    2004-01-01

    Functional lesion studies have yielded new information about the cortical organization of speech perception in the human brain. We will review a number of recent findings, focusing on studies of speech perception that use the techniques of electrocortical mapping by cortical stimulation and hemispheric anesthetization by intracarotid amobarbital.…

  3. Etiology and clinical presentation of birth defects: population based study

    PubMed Central

    Carey, John C; Byrne, Janice L B; Krikov, Sergey; Botto, Lorenzo D

    2017-01-01

    Objective To assess causation and clinical presentation of major birth defects. Design Population based case cohort. Setting Cases of birth defects in children born 2005-09 to resident women, ascertained through Utah’s population based surveillance system. All records underwent clinical re-review. Participants 5504 cases among 270 878 births (prevalence 2.03%), excluding mild isolated conditions (such as muscular ventricular septal defects, distal hypospadias). Main outcome measures The primary outcomes were the proportion of birth defects with a known etiology (chromosomal, genetic, human teratogen, twinning) or unknown etiology, by morphology (isolated, multiple, minors only), and by pathogenesis (sequence, developmental field defect, or known pattern of birth defects). Results Definite cause was assigned in 20.2% (n=1114) of cases: chromosomal or genetic conditions accounted for 94.4% (n=1052), teratogens for 4.1% (n=46, mostly poorly controlled pregestational diabetes), and twinning for 1.4% (n=16, conjoined or acardiac). The 79.8% (n=4390) remaining were classified as unknown etiology; of these 88.2% (n=3874) were isolated birth defects. Family history (similarly affected first degree relative) was documented in 4.8% (n=266). In this cohort, 92.1% (5067/5504) were live born infants (isolated and non-isolated birth defects): 75.3% (4147/5504) were classified as having an isolated birth defect (unknown or known etiology). Conclusions These findings underscore the gaps in our knowledge regarding the causes of birth defects. For the causes that are known, such as smoking or diabetes, assigning causation in individual cases remains challenging. Nevertheless, the ongoing impact of these exposures on fetal development highlights the urgency and benefits of population based preventive interventions. For the causes that are still unknown, better strategies are needed. These can include greater integration of the key elements of etiology, morphology, and

  4. Microbiota-based Signature of Gingivitis Treatments: A Randomized Study.

    PubMed

    Huang, Shi; Li, Zhen; He, Tao; Bo, Cunpei; Chang, Jinlan; Li, Lin; He, Yanyan; Liu, Jiquan; Charbonneau, Duane; Li, Rui; Xu, Jian

    2016-04-20

    Plaque-induced gingivitis can be alleviated by various treatment regimens. To probe the impacts of various anti-gingivitis treatments on plaque microflora, here a double blinded, randomized controlled trial of 91 adults with moderate gingivitis was designed with two anti-gingivitis regimens: the brush-alone treatment and the brush-plus-rinse treatment. In the later group, more reduction in both Plaque Index (TMQHI) and Gingival Index (mean MGI) at Day 3, Day 11 and Day 27 was evident, and more dramatic changes were found between baseline and other time points for both supragingival plaque microbiota structure and salivary metabonomic profiles. A comparison of plaque microbiota changes was also performed between these two treatments and a third dataset where 50 subjects received regimen of dental scaling. Only Actinobaculum, TM7 and Leptotrichia were consistently reduced by all the three treatments, whereas the different microbial signatures of the three treatments during gingivitis relieve indicate distinct mechanisms of action. Our study suggests that microbiota based signatures can serve as a valuable approach for understanding and potentially comparing the modes of action for clinical treatments and oral-care products in the future.

  5. Study of emotion-based neurocardiology through wearable systems

    NASA Astrophysics Data System (ADS)

    Ramasamy, Mouli; Varadan, Vijay

    2016-04-01

    Neurocardiology is the exploration of neurophysiological, neurological and neuroanatomical facets of neuroscience's influence in cardiology. The paraphernalia of emotions on the heart and brain are premeditated because of the interaction between the central and peripheral nervous system. This is an investigative attempt to study emotion based neurocardiology and the factors that influence this phenomena. The factors include: interaction between sleep EEG (electroencephalogram) and ECG (electrocardiogram), relationship between emotion and music, psychophysiological coherence between the heart and brain, emotion recognition techniques, and biofeedback mechanisms. Emotions contribute vitally to the mundane life and are quintessential to a numerous biological and everyday-functional modalities of a human being. Emotions are best represented through EEG signals, and to a certain extent, can be observed through ECG and body temperature. Confluence of medical and engineering science has enabled the monitoring and discrimination of emotions influenced by happiness, anxiety, distress, excitement and several other factors that influence the thinking patterns and the electrical activity of the brain. Similarly, HRV (Heart Rate Variability) widely investigated for its provision and discerning characteristics towards EEG and the perception in neurocardiology.

  6. Studies of the activity of catalysts based on heteropolyacids

    NASA Astrophysics Data System (ADS)

    Turek, Wincenty; Lapkowski, Mieczyslaw; Debiec, Joanna; Krowiak, Agnieszka

    2005-10-01

    The catalytic activity of samples such as PPy(H 4SiW 12O 40), PPy(H 5PMo 10V 2O 40), PPy(H 2Fe(III)PMo 10V 2O 40), PPy(H 3Cu(II)PMo 10V 2O 40) has been examined in two different test reactions. The acid-base and oxidation-reduction properties were studied using the conversion of isopropyl alcohol to propene and acetone. Redox ability of catalysts was examined in the reaction of oxidation of allyl alcohol to glycidol. It was found that the activity of catalysts in the oxidation of allyl alcohol increases as the oxidation properties determined from the conversion of isopropyl alcohol increase. It was also observed that stronger oxidation-reduction properties of the catalyst result in a high rate of the consecutive reaction of glycidol to 3-hydroxypropanone. The phase composition of catalysts was determined by means of X-ray diffraction (XRD).

  7. Longitudinal Study-Based Dementia Prediction for Public Health.

    PubMed

    Kim, HeeChel; Chun, Hong-Woo; Kim, Seonho; Coh, Byoung-Youl; Kwon, Oh-Jin; Moon, Yeong-Ho

    2017-08-30

    The issue of public health in Korea has attracted significant attention given the aging of the country's population, which has created many types of social problems. The approach proposed in this article aims to address dementia, one of the most significant symptoms of aging and a public health care issue in Korea. The Korean National Health Insurance Service Senior Cohort Database contains personal medical data of every citizen in Korea. There are many different medical history patterns between individuals with dementia and normal controls. The approach used in this study involved examination of personal medical history features from personal disease history, sociodemographic data, and personal health examinations to develop a prediction model. The prediction model used a support-vector machine learning technique to perform a 10-fold cross-validation analysis. The experimental results demonstrated promising performance (80.9% F-measure). The proposed approach supported the significant influence of personal medical history features during an optimal observation period. It is anticipated that a biomedical "big data"-based disease prediction model may assist the diagnosis of any disease more correctly.

  8. Improving treatment of neurodevelopmental disorders: recommendations based on preclinical studies.

    PubMed

    Homberg, Judith R; Kyzar, Evan J; Stewart, Adam Michael; Nguyen, Michael; Poudel, Manoj K; Echevarria, David J; Collier, Adam D; Gaikwad, Siddharth; Klimenko, Viktor M; Norton, William; Pittman, Julian; Nakamura, Shun; Koshiba, Mamiko; Yamanouchi, Hideo; Apryatin, Sergey A; Scattoni, Maria Luisa; Diamond, David M; Ullmann, Jeremy F P; Parker, Matthew O; Brown, Richard E; Song, Cai; Kalueff, Allan V

    2016-01-01

    Neurodevelopmental disorders (NDDs) are common and severely debilitating. Their chronic nature and reliance on both genetic and environmental factors makes studying NDDs and their treatment a challenging task. Herein, the authors discuss the neurobiological mechanisms of NDDs, and present recommendations on their translational research and therapy, outlined by the International Stress and Behavior Society. Various drugs currently prescribed to treat NDDs also represent a highly diverse group. Acting on various neurotransmitter and physiological systems, these drugs often lack specificity of action, and are commonly used to treat multiple other psychiatric conditions. There has also been relatively little progress in the development of novel medications to treat NDDs. Based on clinical, preclinical and translational models of NDDs, our recommendations cover a wide range of methodological approaches and conceptual strategies. To improve pharmacotherapy and drug discovery for NDDs, we need a stronger emphasis on targeting multiple endophenotypes, a better dissection of genetic/epigenetic factors or "hidden heritability," and a careful consideration of potential developmental/trophic roles of brain neurotransmitters. The validity of animal NDD models can be improved through discovery of novel (behavioral, physiological and neuroimaging) biomarkers, applying proper environmental enrichment, widening the spectrum of model organisms, targeting developmental trajectories of NDD-related behaviors and comorbid conditions beyond traditional NDDs. While these recommendations cannot be addressed all in once, our increased understanding of NDD pathobiology may trigger innovative cross-disciplinary research expanding beyond traditional methods and concepts.

  9. Microbiota-based Signature of Gingivitis Treatments: A Randomized Study

    PubMed Central

    Huang, Shi; Li, Zhen; He, Tao; Bo, Cunpei; Chang, Jinlan; Li, Lin; He, Yanyan; Liu, Jiquan; Charbonneau, Duane; Li, Rui; Xu, Jian

    2016-01-01

    Plaque-induced gingivitis can be alleviated by various treatment regimens. To probe the impacts of various anti-gingivitis treatments on plaque microflora, here a double blinded, randomized controlled trial of 91 adults with moderate gingivitis was designed with two anti-gingivitis regimens: the brush-alone treatment and the brush-plus-rinse treatment. In the later group, more reduction in both Plaque Index (TMQHI) and Gingival Index (mean MGI) at Day 3, Day 11 and Day 27 was evident, and more dramatic changes were found between baseline and other time points for both supragingival plaque microbiota structure and salivary metabonomic profiles. A comparison of plaque microbiota changes was also performed between these two treatments and a third dataset where 50 subjects received regimen of dental scaling. Only Actinobaculum, TM7 and Leptotrichia were consistently reduced by all the three treatments, whereas the different microbial signatures of the three treatments during gingivitis relieve indicate distinct mechanisms of action. Our study suggests that microbiota based signatures can serve as a valuable approach for understanding and potentially comparing the modes of action for clinical treatments and oral-care products in the future. PMID:27094556

  10. An approach to space weather studies from ground based observations

    NASA Astrophysics Data System (ADS)

    Minarovjech, M.; Rušin, V.; Rybanský, M.; Kudela, K.; Kollár, V.

    2004-10-01

    We use daily values of the green corona hole areas, as prepared from the ground-based observations above the E-limb of the Sun and cosmic ray flux observed at Climax and Huancayo/Haleakala, to study a relation between them during a long-term period. A cross-correlation method has been used in the period 1953-2002 (the end of solar cycle 18 to mid-cycle 23). There were found green coronal hole areas that precede the cosmic ray of 200 - 270 days, with the maximum of 230 days (an average of 8 months). The 27-day rotational periodicity is stored around the maximum of correlation coefficients that reached values of 0.78 and 0.72, respectively. This correlation could be used to forecast the level of the cosmic ray daily flux at neutron monitor energies. We try to explain this behavior in a framework of the total coronal mass and its expansion into the heliosphere.

  11. Evaluating a problem based learning course: an action research study.

    PubMed

    Walker, J; Bailey, S; Brasell-Brian, R; Gould, S

    2001-03-01

    Problem based learning (PBL) has been widely used in the United States, United Kingdom and Australasia in undergraduate nursing education to develop critical thinking and problem solving skills. PBL has been used since 1996 in a Bachelor of Nursing course at a New Zealand tertiary institution, and several modifications have been made to foster effective learning. The 'pure' PBL process has been adapted to move students gradually from teacher direction to taking responsibility for their learning. This has provided the opportunity for students to develop critical thinking, problem solving, information retrieval and evaluation skills, and group process skills over an 18-week period. Because rigorous evaluation of these changes had not been formally undertaken, the purpose of this study was to evaluate how the current format was developing students' understanding and integration of knowledge. Two cycles of the action research method (Cardno and Piggot-Irvine, 1994) were used, involving 4 lecturers and 17 students. Data was collected both quantitatively and qualitatively over a 16-week period. Findings indicated the importance of: explaining the purpose and process of PBL; communicating in detail the role of both students and lecturers; keeping communication lines open; addressing timetabling issues and valuing this method of learning for nursing practice. Implications for nursing education are addressed.

  12. Rehabilitation regimes based upon psychophysical studies of prosthetic vision

    NASA Astrophysics Data System (ADS)

    Chen, S. C.; Suaning, G. J.; Morley, J. W.; Lovell, N. H.

    2009-06-01

    Human trials of prototype visual prostheses have successfully elicited visual percepts (phosphenes) in the visual field of implant recipients blinded through retinitis pigmentosa and age-related macular degeneration. Researchers are progressing rapidly towards a device that utilizes individual phosphenes as the elementary building blocks to compose a visual scene. This form of prosthetic vision is expected, in the near term, to have low resolution, large inter-phosphene gaps, distorted spatial distribution of phosphenes, restricted field of view, an eccentrically located phosphene field and limited number of expressible luminance levels. In order to fully realize the potential of these devices, there needs to be a training and rehabilitation program which aims to assist the prosthesis recipients to understand what they are seeing, and also to adapt their viewing habits to optimize the performance of the device. Based on the literature of psychophysical studies in simulated and real prosthetic vision, this paper proposes a comprehensive, theoretical training regime for a prosthesis recipient: visual search, visual acuity, reading, face/object recognition, hand-eye coordination and navigation. The aim of these tasks is to train the recipients to conduct visual scanning, eccentric viewing and reading, discerning low-contrast visual information, and coordinating bodily actions for visual-guided tasks under prosthetic vision. These skills have been identified as playing an important role in making prosthetic vision functional for the daily activities of their recipients.

  13. Structural studies of enzyme-based microfluidic biofuel cells

    NASA Astrophysics Data System (ADS)

    Togo, Makoto; Takamura, Akimasa; Asai, Tatsuya; Kaji, Hirokazu; Nishizawa, Matsuhiko

    An enzyme-based glucose/O 2 biofuel cell was constructed within a microfluidic channel to study the influence of electrode configuration and fluidic channel height on cell performance. The cell was composed of a bilirubin oxidase (BOD)-adsorbed O 2 cathode and a glucose anode prepared by co-immobilization of glucose dehydrogenase (GDH), diaphorase (Dp) and VK 3-pendant poly- L-lysine. The consumption of O 2 at the upstream cathode protected the downstream anode from interfering O 2 molecules, and consequently improved the cell performance (maximum cell current) ca. 10% for the present cell. The cell performance was also affected by the channel height. The output current and power of a 0.1 mm-height cell was significantly less than those of a 1 mm-height cell because of the depletion of O 2, as determined by the shape of the E- I curve at the cathode. On the other hand, the volume density of current and power was several times higher for the narrower cell.

  14. Accounting for Relatedness in Family Based Genetic Association Studies

    PubMed Central

    McArdle, P.F.; O’Connell, J.R.; Pollin, T.I.; Baumgarten, M.; Shuldiner, A.R.; Peyser, P.A.; Mitchell, B.D.

    2007-01-01

    Objective Assess the differences in point estimates, power and type 1 error rates when accounting for and ignoring family structure in genetic tests of association. Methods We compare by simulation the performance of analytic models using variance components to account for family structure and regression models that ignore relatedness for a range of possible family based study designs (i.e., sib pairs vs. large sibships vs. nuclear families vs. extended families). Results Our analyses indicate that effect size estimates and power are not significantly affected by ignoring family structure. Type 1 error rates increase when family structure is ignored, as density of family structures increases, and as trait heritability increases. For discrete traits with moderate levels of heritability and across many common sampling designs, type 1 error rates rise from a nominal 0.05 to 0.11. Conclusion Ignoring family structure may be useful in screening although it comes at a cost of a increased type 1 error rate, the magnitude of which depends on trait heritability and pedigree configuration. PMID:17570925

  15. Performance Study of optical Modulator based on electrooptic effect

    NASA Astrophysics Data System (ADS)

    Palodiya, V.; Raghuwanshi, S. K.

    2016-08-01

    In this paper, we have studied and derive performance parameter of highly integrated Lithium Niobate optical modulator. This is a chirp free modulator having low switching voltage and large bandwidth. For an external modulator in which travelling-wave electrodes length L imposed the modulating switching voltage, the product of Vπ and L is fixed for a given electro optic material Lithium Niobate. We investigate to achieve a low Vπ by both magnitude of the electro-optic coefficient for a wide variety of electro-optic materials. A Sellmeier equation for the extraordinary index of congruent lithium niobate is derived. For phase-matching, predictions are accmate for temperature between room temperature 250°C and wavelength ranging from 0.4 to 5µm. The Sellmeier equations predict more accmately refractive indices at long wavelengths. Theoretical result is confirmed by simulated results. We have analysed the various parameters such as switching voltage, device performance index, time constant, transmittance, cut-off frequency, 3-dB bandwidth, power absorption coefficient and transmission bit rate of Lithium Niobate optical Modulator based on electro -optic effect.

  16. Pattern of unintentional burns: A hospital based study from Pakistan.

    PubMed

    Adil, Syed Omair; Ibran, Ehmer-Al; Nisar, Nighat; Shafique, Kashif

    2016-09-01

    Burns are major cause of morbidity and mortality in developing countries. Better understanding of the nature and extent of injury remains the major and only available way to halt the occurrence of the event. The present study was conducted to determine the prevalence of by self and by other unintentional burn, their comparison and the possible mode of acquisition by obtaining the history of exposure to known risk factors. A cross-sectional questionnaire based survey was conducted in Burns Centre of Civil Hospital Karachi, Pakistan and 324 hospitalized adult patients with unintentional burns were consecutively interviewed during August 2013 to February 2014. Information was collected on socio-demographic profile. The source of burn, affected body part and place of injury acquisition in terms of home, outside or work were also noted. Logistic regression model was conducted using SPSS software. Out of 324 patients, 295 (91%) had unintentional burn by self and 29 (9%) had unintentional burn by others. Male gender were 2.37 times and no schooling were 1.75 times more likely to have self-inflicted unintentional burn. Lower limb and head and neck were less likely to involve in unintentional burn by self. The burden of unintentional burn by self was considerably higher. Male gender and no schooling were found more at risk to have unintentional burn by self. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

  17. Satellite-Based Study of Glaciers Retreat in Northern Pakistan

    NASA Astrophysics Data System (ADS)

    Munir, Siraj

    Glaciers serve as a natural regulator of regional water supplies. About 16933 Km 2 area of glaciers is covered by Pakistan. These glaciers are enormous reservoirs of fresh water and their meltwater is an important resource which feed rivers in Pakistan. Glacier depletion, especially recent melting can affect agriculture, drinking water supplies, hydro-electric power, and ecological habitats. This can also have a more immediate impact on Pakistan's economy that depends mainly on water from glacier melt. Melting of seasonal snowfall and permanent glaciers has resulted not only in reduction of water resources but also caused flash floods in many areas of Pakistan. With the advent of satellite technology, using optical and SAR data the study of glaciers, has become possible. Using temporal data, based on calculation of snow index, band ratios and texture reflectance it has been revealed that the rate of glacier melting has increased as a consequent of global warming. Comparison of Landsat images of Batura glacier for October 1992 and October 2000 has revealed that there is a decrease of about 17 sq km in Batura glaciers. Although accurate changes in glacier extent cannot be assessed without baseline information, these efforts have been made to analyze future changes in glaciated area.

  18. Hospital occupancy and discharge strategies: a simulation-based study.

    PubMed

    Qin, Shaowen; Thompson, Campbell; Bogomolov, Tim; Ward, Dale; Hakendorf, Paul

    2017-08-01

    Increasing demand for hospital services has resulted in more arrivals to emergency department (ED), increased admissions, and, quite often, access block and ED congestion, along with patients' dissatisfaction. Cost constraints limit an increase in the number of hospital beds, so alternative solutions need to be explored. To propose and test different discharge strategies, which, potentially, could reduce occupancy rates in the hospital, thereby improving patient flow and minimising frequency and duration of congestion episodes. We used a simulation approach using HESMAD (Hospital Event Simulation Model: Arrivals to Discharge) - a sophisticated simulation model capturing patient flow through a large Australian hospital from arrival at ED to discharge. A set of simulation experiments with a range of proposed discharge strategies was carried out. The results were tabulated, analysed and compared using common hospital occupancy indicators. Simulation results demonstrated that it is possible to reduce significantly the number of days when a hospital runs above its base bed capacity. In our case study, this reduction was from 281.5 to 22.8 days in the best scenario, and reductions within the above range under other scenarios considered. Some relatively simple strategies, such as 24-h discharge or discharge/relocation of long-staying patients, can significantly reduce overcrowding and improve hospital occupancy rates. Shortening administrative and/or some treatment processes have a smaller effect, although the latter could be easier to implement. © 2017 Royal Australasian College of Physicians.

  19. Central poststroke pain: a population-based study.

    PubMed

    Klit, Henriette; Finnerup, Nanna Brix; Andersen, Grethe; Jensen, Troels Staehelin

    2011-04-01

    Central poststroke pain (CPSP) is a specific pain condition arising as a direct consequence of a cerebrovascular lesion. There is limited knowledge about the epidemiology and clinical characteristics of this often neglected but important consequence of stroke. In this population-based study, a questionnaire was sent out to all (n=964) stroke patients identified through the Danish National Indicator Project Stroke Database in Aarhus County, Denmark, between March 2004 and February 2005. All surviving patients who fulfilled 4 questionnaire criteria for possible CPSP (n=51) were selected for further clinical examination, and their pain was classified by using stringent and well-defined criteria and a detailed, standardized clinical examination. The minimum prevalence of definite or probable CPSP in this population is 7.3% and the prevalence of CPSP-like dysesthesia or pain is 8.6%. Pinprick hyperalgesia was present in 57%, cold allodynia in 40%, and brush-evoked dysesthesia in 51% of patients with CPSP. Because of its negative impact on quality of life and rehabilitation, pain is an important symptom to assess in stroke survivors.

  20. Neutrino-nucleus reactions based on recent structure studies

    SciTech Connect

    Suzuki, Toshio

    2015-05-15

    Neutrino-nucleus reactions are studied with the use of new shell model Hamiltonians, which have proper tensor components in the interactions and prove to be successful in the description of Gamow-Teller (GT) strengths in nuclei. The new Hamiltonians are applied to obtain new neutrino-nucleus reaction cross sections in {sup 12}C, {sup 13}C, {sup 56}Fe and {sup 56}Ni induced by solar and supernova neutrinos. The element synthesis by neutrino processes in supernova explosions is discussed with the new cross sections. The enhancement of the production yields of {sup 7}Li, {sup 11}B and {sup 55}Mn is obtained while fragmented GT strength in {sup 56}Ni with two-peak structure is found to result in smaller e-capture rates at stellar environments. The monopole-based universal interaction with tensor force of π+ρ meson exchanges is used to evaluate GT strength in {sup 40}Ar and ν-induced reactions on {sup 40}Ar. It is found to reproduce well the experimental GT strength in {sup 40}Ar.

  1. Systematic mapping study of data mining-based empirical studies in cardiology.

    PubMed

    Kadi, Ilham; Idri, Ali; Fernandez-Aleman, José Luis

    2017-07-01

    Data mining provides the methodology and technology to transform huge amount of data into useful information for decision making. It is a powerful process to extract knowledge and discover new patterns embedded in large data sets. Data mining has been increasingly used in medicine, particularly in cardiology. In fact, data mining applications can greatly benefits all parts involved in cardiology such as patients, cardiologists and nurses. This article aims to perform a systematic mapping study so as to analyze and synthesize empirical studies on the application of data mining techniques in cardiology. A total of 142 articles published between 2000 and 2015 were therefore selected, studied and analyzed according to the four following criteria: year and channel of publication, research type, medical task and empirical type. The results of this mapping study are discussed and a list of recommendations for researchers and cardiologists is provided.

  2. Exploring Global Change In Place-Based Case Studies

    NASA Astrophysics Data System (ADS)

    Moosavi, S. C.

    2011-12-01

    The complexity of global climate change makes the subject challenging for the average student, particularly given the nuanced feedbacks and exceptions to the general "warming" or "drying" trend that may be experienced at the local and regional level at which most people experience geologic processes. Geoscience educators can reduce these barriers and draw in student learners by adopting a place-based approach to teaching and researching geologic principles that relate to global change. Assisting students in recognizing and understanding the geologic environment in which they live and study has the side benefit of making the potential effect of climate change tangible. This presentation will review several approaches for using place-based case studies to explore global climate change issues in large lecture, small seminar, field research and service learning environments. The special place project used in large introductory physical geology courses requires each student to select a place familiar and unique to them for an in depth study of the common course content as the semester progresses. Students are specifically tasked with identifying how their site came to be, the geologic processes that act upon it today, how the site may have been different during the last glacial advance and how global climate change (specifically warming of 3OC over 50 years) might impact the site. The concept that change has occurred at the student's site in the past, even far from glacial environments, opens students to the scale of potential anthropogenic climate change. A freshman seminar Global Warming & Climate Change - Service in Preparation for Climate Change: The Second Battle of New Orleans focused on the environmental threats to New Orleans and southeastern Louisiana resulting from regional land use decisions in the centuries before Hurricane Katrina, and the threat that global change relating to sea level rise, acceleration of the hydrologic cycle and intensification of

  3. Agent-Based vs. Equation-based Epidemiological Models:A Model Selection Case Study

    SciTech Connect

    Sukumar, Sreenivas R; Nutaro, James J

    2012-01-01

    This paper is motivated by the need to design model validation strategies for epidemiological disease-spread models. We consider both agent-based and equation-based models of pandemic disease spread and study the nuances and complexities one has to consider from the perspective of model validation. For this purpose, we instantiate an equation based model and an agent based model of the 1918 Spanish flu and we leverage data published in the literature for our case- study. We present our observations from the perspective of each implementation and discuss the application of model-selection criteria to compare the risk in choosing one modeling paradigm to another. We conclude with a discussion of our experience and document future ideas for a model validation framework.

  4. Bladder cancer in Spain 2011: population based study.

    PubMed

    Miñana, B; Cózar, J M; Palou, J; Unda Urzaiz, M; Medina-Lopez, R A; Subirá Ríos, Jorge; de la Rosa-Kehrmann, F; Chantada-Abal, V; Lozano, F; Ribal, Maria J; Rodríguez Fernández, E; Castiñeiras Fernández, J; Concepción Masip, Tomás; Requena-Tapia, M J; Moreno-Sierra, J; Hevia, M; Gómez Rodríguez, A; Martínez-Ballesteros, C; Ramos, M; Amón Sesmero, José H; Pizá Reus, P; Bohorquez Barrientos, A; Rioja Sanz, Carlos; Gomez-Pascual, J Angel; Hidalgo Zabala, E; Parra Escobar, J L; Serrano, O

    2014-02-01

    We estimate the annual incidence of bladder cancer in Spain and describe the clinical profile of patients with bladder cancer enrolled in a population based study. Using the structure of the Spanish National Health System as a basis, in 2011 the AEU (Spanish Association of Urology) conducted this study with a representative sample from 26 public hospitals and a reference population of 10,146,534 inhabitants, comprising 21.5% of the Spanish population. A total of 4,285 episodes of bladder cancer were diagnosed, of which 2,476 (57.8%) were new cases and 1,809 (42.2%) were cases of recurrence, representing an estimated 11,539 new diagnoses annually in Spain. The incidence of bladder cancer in Spain, age adjusted to the standard European population, was 20.08 cases per 100,000 inhabitants (95% CI 13.9, 26.3). Of patients diagnosed with a first episode of bladder cancer 84.3% were male, generally older than 59 years (81.7%) with a mean ± SD age of 70.5 ± 11.4 years. Of these patients 87.5% presented with some type of clinical symptom, with macroscopic hematuria (90.8%) being the most commonly detected. The majority of primary tumors were nonmuscle invasive (76.7%) but included a high proportion of high grade tumors (43.7%). According to the ISUP (International Society of Urologic Pathology)/WHO (2004) classification 51.1% was papillary high grade carcinoma. Carcinoma in situ was found in 2.2% of primary and 5.8% of recurrent cases. The incidence of bladder cancer in Spain, age adjusted to the standard European population, confirms that Spain has one of the highest incidences in Europe. Most primary nonmuscle invasive bladder cancer corresponded to high risk patients but with a low detected incidence of carcinoma in situ. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  5. Evidence-based medicine. Interpreting studies and setting policy.

    PubMed

    Woolf, S H; George, J N

    2000-08-01

    The ascendancy of EBM has been accompanied by a greater awareness of its shortcomings. It is increasingly evident from the cost, length, and difficulty of performing RCTs that studies cannot be launched to address every question in medicine. Good evidence is often lacking in medicine. Epistomologists question the very notions of evidence and the suitability of current study designs and measurement tools to research the salient issues of concern to patients and others concerned with quality. Lack of evidence of effectiveness does not prove ineffectiveness, yet, in reaction to EBM, insurance companies and government often make this inference to justify decisions to withhold coverage or research support. The unbridled enthusiasm for the evidence-based practice guideline of the early 1990s has been tempered by a more mature understanding of its limitations. Not many practice guidelines are developed well, and the implementation of flawed guidelines can cause harm. The seven-step process outlined earlier is slow, laborious, and expensive (sometimes costing hundreds of thousands of dollars). Moreover, there is little evidence that either the rigor of the methods or the guidelines themselves have a meaningful effect on practice behavior or patient outcomes. To the most cynical observers, the only consistent beneficiaries of guidelines are payers, who use guidelines with considerable success in reducing costs, lengths of stay, and utilization rates. Even ardent advocates of guidelines acknowledge the evidence that disseminating reviews and recommendations, by itself, fails to motivate clinicians to increase delivery of effective interventions and to abandon ineffective ones. This absence of response has stimulated a closer look at the barriers to behavior change and the design of thoughtful implementation strategies that begin with, but reach beyond, simple guidelines. Tools such as reminder systems, standing orders, academic detailing, peer review and audit, feedback, and

  6. Optothermal Raman Studies of Thermal Properties of Graphene Based Films

    NASA Astrophysics Data System (ADS)

    Malekpour, Hoda

    Efficient thermal management is becoming a critical issue for development of the next generation of electronics. As the size of electronic devices shrinks, the dissipated power density increases, demanding a better heat removal. The discovery of graphene's unique electrical and thermal properties stimulated interest of electronic industry to development of graphene based technologies. In this dissertation, I report the results of my investigation of thermal properties of graphene derivatives and their applications in thermal management. The dissertation consists of three parts. In the first part, I investigated thermal conductivity of graphene laminate films deposited on thermally insulating polyethylene terephthalate substrates. Graphene laminate is made of chemically derived graphene and few layer graphene flakes packed in overlapping structure. Two types of graphene laminate were studied: as deposited and compressed. The thermal conductivity of the laminate was found to be in the range from 40 W/mK to 90 W/mK at room temperature. It was established that the average size and the alignment of graphene flakes are parameters dominating the heat conduction. In the second part of this dissertation, I investigated thermal conductivity of chemically reduced freestanding graphene oxide films. It was found that the in-plane thermal conductivity of graphene oxide can be increased significantly using chemical reduction and temperature treatment. Finally, I studied the effect of defects on thermal conductivity of suspended graphene. The knowledge of the thermal conductivity dependence on the concentration of defects can shed light on the strength of the phonon - point defect scattering in two-dimensional materials. The defects were introduced to graphene in a controllable way using the low-energy electron beam irradiation. It was determined that as the defect density increases the thermal conductivity decreases down to about 400 W/mK, and then reveal saturation type behavior

  7. Aeroelastic Optimization Study Based on X-56A Model

    NASA Technical Reports Server (NTRS)

    Li, Wesley; Pak, Chan-Gi

    2014-01-01

    A design process which incorporates the object-oriented multidisciplinary design, analysis, and optimization (MDAO) tool and the aeroelastic effects of high fidelity finite element models to characterize the design space was successfully developed and established. Two multidisciplinary design optimization studies using an object-oriented MDAO tool developed at NASA Armstrong Flight Research Center were presented. The first study demonstrates the use of aeroelastic tailoring concepts to minimize the structural weight while meeting the design requirements including strength, buckling, and flutter. A hybrid and discretization optimization approach was implemented to improve accuracy and computational efficiency of a global optimization algorithm. The second study presents a flutter mass balancing optimization study. The results provide guidance to modify the fabricated flexible wing design and move the design flutter speeds back into the flight envelope so that the original objective of X-56A flight test can be accomplished.

  8. COMSOL-based Nuclear Reactor Kinetics Studies at the HFIR

    SciTech Connect

    Chandler, David; Freels, James D; Maldonado, G Ivan; Primm, Trent

    2011-01-01

    The computational ability to accurately predict the dynamic behavior of a nuclear reactor core in response to reactivity-induced perturbations is an important subject in reactor physics. Space-time and point kinetics methodologies were developed for the purpose of studying the transient-induced behavior of the High Flux Isotope Reactor s (HFIR) compact core. The space-time simulations employed the three-energy-group neutron diffusion equations, and transients initiated by control cylinder and hydraulic tube rabbit ejections were studied. The work presented here is the first step towards creating a comprehensive multiphysics methodology for studying the dynamic behavior of the HFIR core during reactivity perturbations. The results of these studies show that point kinetics is adequate for small perturbations in which the power distribution is assumed to be time-independent, but space-time methods must be utilized to determine localized effects.

  9. Hooking the Geographer in Children with Field-Based Studies

    ERIC Educational Resources Information Center

    Krall, Florence; And Others

    1978-01-01

    Suggests projects to help elementary students learn about man-land relationships through field experience, inquiry techniques, and a thematic, interdisciplinary approach. Children study a natural community, a human community, solid wastes, and energy conservation. (Author/AV)

  10. Integrated Genome-Based Studies of Shewanella Ecophysiology

    SciTech Connect

    Zhou, Jizhong; He, Zhili

    2014-04-08

    As a part of the Shewanella Federation project, we have used integrated genomic, proteomic and computational technologies to study various aspects of energy metabolism of two Shewanella strains from a systems-level perspective.

  11. Hooking the Geographer in Children with Field-Based Studies

    ERIC Educational Resources Information Center

    Krall, Florence; And Others

    1978-01-01

    Suggests projects to help elementary students learn about man-land relationships through field experience, inquiry techniques, and a thematic, interdisciplinary approach. Children study a natural community, a human community, solid wastes, and energy conservation. (Author/AV)

  12. Low energy cosmic ray studies from a lunar base

    NASA Technical Reports Server (NTRS)

    Wiedenbeck, Mark E.

    1990-01-01

    Studies of cosmic ray nuclei with energies less than about 7 GeV/nucleon in low earth orbit are hampered by the geomagnetic field. Even in high inclination orbits these effects can be significant. The lunar surface (or lunar orbit) provides an attractive site for carrying out low energy cosmic ray studies which require large detectors. The rationale and requirements for this type of experiment are described.

  13. On schizophrenia prognosis based on data of a clinicogenetical study.

    PubMed

    Kornetov, A N; Majburd, E D; Samokhvalov, V P

    1979-01-01

    Peculiarities of the clinical picture of schizophrenia were studied in a group of patients in which less than a half (785) patients had the aggravating fact and in two hereditary-aggravated groups: siblings (109 patients) and parents--children (118 pairs). Prognostic significance of the genetic factor, sex and age was studied as related to peculiarities of the clinical picture of schizophrenia. Hereditary aggravation is shown to be of a decisive importance for schizophrenia prognosis.

  14. Low energy cosmic ray studies from a lunar base

    SciTech Connect

    Wiedenbeck, M.E. Department of Physics, University of Chicago, Chicago, IL )

    1990-03-15

    Studies of cosmic ray nuclei with energies {approx lt}7 GeV/nucleon in low Earth orbit are hampered by the geomagnetic field. Even in high inclination orbits these effects can be significant. The lunar surface (or lunar orbit) provides an attractive site for carrying out low energy cosmic ray studies which require large detectors. The rationale and requirements for this type of experiment are described.

  15. Base Intrusion Schottky Barrier IR Assessment Camera Study.

    DTIC Science & Technology

    1981-09-01

    detection line sensors. The program includes coverage studies to determine requirements for array size and camera complexity to provide cost-effective...addition, hardware studies are being conducted to determine design requirements and specifications for development and for future field testing of an...Since the early 1970s, RCA has been actively engaged in the development of IRI Schottky barrier line and area FPAs for the Air Force RADC Deputy for

  16. Mortality in Autism: A Prospective Longitudinal Community-Based Study

    ERIC Educational Resources Information Center

    Gillberg, Christopher; Billstedt, Eva; Sundh, Valter; Gillberg, I. Carina

    2010-01-01

    The purposes of the present study were to establish the mortality rate in a representative group of individuals (n = 120) born in the years 1962-1984, diagnosed with autism/atypical autism in childhood and followed up at young adult age (greater than or equal to 18 years of age), and examine the risk factors and causes of death. The study group,…

  17. Experimentally-Based Ocean Acoustic Propagation and Coherence Studies

    DTIC Science & Technology

    2011-09-01

    temperate deep -ocean sound channel. Reliable predictions of temporal and spatial variability of received underwater sound can improve processing and...3000 Hz. For the deep -ocean sound channel, the objective is to better characterize coupled-mode propagation at 50 to 100 Hz, which may have some...Sea spring 2007 ONR/Taiwan NLIWI acoustics experiment [Reeder et al., 2010], and the Shelfbreak PRIMER study. For deep -water studies, data are from the

  18. Undernutrition among Indian men: a study based on NFHS-3.

    PubMed

    Patil, Yashwant Pandharinath; Shinde, Ramkrishna Lahu

    2014-11-01

    The objective of this study was to evaluate zonal and state-wise prevalence and risk factors of undernutrition among Indian men in the age-group of 15 to 54 years based on sampled data of 74,369 respondents from the National Family Health Survey-3. A common anthropometric measure, body mass index, is used to determine the prevalence as it is considered to be a good measure of undernutrition. Overall, 28.6% (SE=0.17%) of Indian men are classified as underweight, and 52.5% (SE=0.62%) of the younger age-group (15-19 years) are underweight. The highest prevalence of underweight men in Indian states is observed in Tripura (39.8%; SE=1.85%), followed by Rajasthan (39.3%; SE=1.28%), Chhattisgarh (37.2%; SE=1.3%), and Gujarat (35.7%; SE=1.3%). The highest and lowest prevalence among zones are reported for central (34.5%; SE=0.39%) and northeast (18%; SE=0.34%) zones, respectively. The bivariate analysis using chi-square test concludes the significant association (p<.001) between the body mass index groups and each of the explanatory variable. Significant difference (p≤.002) is reported in the mean heights of underweight and non-underweight men among four out of six zones of India. From multivariate logistic regression analysis, we observed that for India as a whole, men with no education, low/medium standard of living, and the younger age-group (15-19 years) have significantly (p<.001) higher chances of being underweight. We also observed similar results for many Indian states at different significance levels. In conclusion, the distribution of underweight in India remains segregated by socioeconomic status. © The Author(s) 2014.

  19. Hypervolemia for hypertension pathophysiology: a population-based study.

    PubMed

    Hür, Ender; Özişik, Melih; Ural, Cihan; Yildiz, Gürsel; Mağden, Kemal; Köse, Sennur Budak; Köktürk, Füruzan; Büyükuysal, Çağatay; Yildirim, Ibrahim; Süleymanlar, Gültekin; Ateş, Kenan; Duman, Soner

    2014-01-01

    Hypertension and hypervolemia relationship was proven among renal disease, although it is not known in normal population. Present study determines the fluid distribution defects in relation to blood pressure. In a population-based survey in Turkey demographics, height, weight, blood pressure, urine analysis, and serum creatinine measurements were recorded. Bioimpedance measured with the Body Composition Monitor. Total 2034 population of 71.6% male, mean age 47 ± 12.6 (18-89) years, systolic blood pressure (SBP) 134.7 ± 20, diastolic blood pressure 77.9 ± 11.6 mmHg. Body mass index (BMI) was 28.5 ± 4.5 (15.8-50.6) kg/m(2); overhydration was 0.05 ± 1.05 L. There was a correlation between extracellular water (ECW)/height and SBP (r = 0.21, P < 0.001). Receiver operating characteristic (ROC) curve with the performance of 0.60 (P < 0.001) that showed cut-off value of ECW/height was 10.06 L/m, with the 69% sensitivity and 45% specificity for SBP: 140 mmHg values. Risk factors for high SBP were increase of ECW/Height, age, BMI and presence of diabetes. ECW/height, SBP, and fat tissue index (FTI) increased in BMI categories (low, normal, and obese) and in diabetics. SBP and FTI were lower in smokers. High blood pressure may be accompanied by increased extracellular volume indices. In the future volume status assessment could be of use in evaluating the effectiveness of pharmacological intervention in the treatment of hypertension.

  20. Stratification of ALS patients' survival: a population-based study.

    PubMed

    Marin, Benoît; Couratier, Philippe; Arcuti, Simona; Copetti, Massimiliano; Fontana, Andrea; Nicol, Marie; Raymondeau, Marie; Logroscino, Giancarlo; Preux, Pierre Marie

    2016-01-01

    The natural history of amyotrophic lateral sclerosis (ALS) and patient risk stratification are areas of considerable research interest. We aimed (1) to describe the survival of a representative cohort of French ALS patients, and (2) to identify covariates associated with various patterns of survival using a risk classification analysis. ALS patients recruited in the FRALim register (2000-2013) were included. Time-to-death analyses were performed using Kaplan-Meier method and Cox model. A recursive partitioning and amalgamation (RECPAM) algorithm analysis identified subgroups of patients with different patterns of survival. Among 322 patients, median survival times were 26.2 and 15.6 months from time of onset and of diagnosis, respectively. Four groups of patients were identified, depending on their baseline characteristics and survival (1) ALSFRS-R slope >0.46/month and definite or probable ALS (median survival time (MST) 10.6 months); (2) ALSFRS-R slope >0.46/month and possible or probable laboratory-supported ALS (MST: 18.1 months); (3) ALSFRS-R slope ≤0.46/month and definite or probable ALS (MST: 22.5 months), and (4) ALSFRS-R slope ≤0.46/month and possible or probable laboratory-supported ALS (MST: 37.6 months). Median survival time is among the shortest ever reported by a worldwide population-based study. This is probably related to the age structure of the patients (the oldest identified to date), driven by the underlying population (30 % of subjects older than 60 years). Further research in the field of risk stratification could help physicians better anticipate prognosis of ALS patients, and help improve the design of randomized controlled trials.

  1. Associations of childhood eczema severity: A US population based study

    PubMed Central

    Silverberg, Jonathan I.; Simpson, Eric L.

    2014-01-01

    Little is known about predictors of eczema severity in the US population. We sought to determine the distribution and associations of childhood eczema severity in the US. We analyzed data from the 2007 National Survey of Children's Health, a prospective questionnaire-based study of a nationally representative sample of 91,642 children (0-17yr). The prevalence of childhood eczema was 12.97% (95% confidence interval [95% CI]=12.42–13.53); 67.0% (95% CI: 64.8–69.2) had mild, 26.0% (95% CI: 23.9–28.1) moderate and 7.0% (95% CI: 5.8–8.3) severe disease. There was significant statewide-variation of the distribution of eczema severity (Rao-Scott chi square, P=0.004), with highest rates of severe disease in Northeastern and Midwestern states. In univariate models, eczema severity was increased with older age, African-American and Hispanic race/ethnicity, lower household income, oldest child in the family, home with a single mother, lower paternal/maternal education level, maternal general health, maternal/paternal emotional health, dilapidated housing and garbage on the streets. In multivariate survey logistic regression models using stepwise and backward selection, moderate–severe eczema was associated with older age, lower household income and fair or poor maternal health, but inversely associated with birthplace outside the US. These data indicate that environmental and/or lifestyle factors play an important role in eczema severity. PMID:24819283

  2. Mammographic density and urbanization: a population-based screening study.

    PubMed

    Viel, Jean-François; Rymzhanova, Raouchan

    2012-03-01

    The high incidence of female breast cancer that has been consistently reported in urban areas could be mediated by breast density, which is considered to reflect the cumulative exposure of breast tissues to hormones. The aim of this study was to assess how mammographic density varies by the degree of urbanization. The population consisted of 55,597 cancer-free women, aged 50-59 years, who participated in a French breast cancer screening programme (Franche-Comté region) between 2005 and 2009. Ordered logistic regression was run with mammographic density as the outcome, and degree of urbanization as the independent variable, while adjusting for some known confounding factors. Multiple imputation was used to deal with missing data. A significant positive linear trend with urbanization was found in a univariate approach (P trend <10(-3)), and after adjusting for risk factors (P trend = 10(-3)). A negative and highly significant association with mammographic density was highlighted both for age at the time of mammography (odds ratio (OR) 0.41, 95% confidence interval (CI) 0.39-0.43, per 10 years), and for low socioeconomic status (OR 0.71, 95% CI 0.67-0.75). The OR for hormone replacement therapy use was 1.51 (95% CI 1.43-1.58). Knowledge of this urbanization gradient in density (whatever its mechanism) may help to identify women who may require full-field digital mammography for the early detection of breast cancer, and could assist primary care providers in recommending the best screening strategy in a risk factor-based approach.

  3. Synthesis, structural, spectroscopic and biological studies of Schiff base complexes

    NASA Astrophysics Data System (ADS)

    Diab, M. A.; El-Sonbati, A. Z.; Shoair, A. F.; Eldesoky, A. M.; El-Far, N. M.

    2017-08-01

    Schiff base ligand 4-((pyridin-2- yl)methyleneamino)-1,2-dihydro-2,3-dimethyl-1-phenylpyrazol-5-one (PDMP) and its complexes were prepared and characterized on the basis of elemental analysis, IR, mass spectra and thermogravimetric analysis. All results confirm that the complexes have 1:1 (M: PMDP) stoichiometric formula [M(PMDP)Cl2H2O ] (M = Cu(II), Co(II), Ni(II) and Mn(II)), [Cd(PMDP)Cl2] and the ligand behaves as a bi/tridentate forming five-membered chelating ring towards the metal ions, bonding through azomethine nitrogen/exocyclic carbonyl oxygen, azomethine pyridine nitrogen and exocyclic carbonyl oxygen. The shift in the band positions of the groups involved in coordination has been utilized to estimate the metal-nitrogen and/or oxygen bond lengths. The complexes of Co(II), Ni(II) and Cu(II) are paramagnetic and the magnetic as well as spectral data suggest octahedral geometry, whereas the Cd(II) complex is tetrahedral. The XRD studies show that both the ligand and its metal complexes (1 and 3) show polycrystalline with crystal structure. Molecular docking was used to predict the binding between PMDP ligand and the receptors. The corrosion inhibition of mild steel in 2 M HCl solution by PDMP was explored utilizing potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and (EFM) electrochemical frequency modulation method. Potentiodynamic polarization demonstrated that PDMP compound is mixed-type inhibitor. EIS spectra exhibit one capacitive loop and confirm the protective ability. The percentage of inhibition efficiency was found to increase with increasing the inhibitor concentration.

  4. Recurrent Wheezing in Infants: A Population-Based Study.

    PubMed

    Belhassen, Manon; De Blic, Jacques; Laforest, Laurent; Laigle, Valérie; Chanut-Vogel, Céline; Lamezec, Liliane; Brouard, Jacques; Fauroux, Brigitte; de Pouvourville, Gérard; Ginoux, Marine; Van Ganse, Eric

    2016-04-01

    Recurrent wheezing (RW) has a significant impact on infants, caregivers, and society, but morbidity and related medical resource utilization (MRU) have not been thoroughly explored. The burden of RW needs to be documented with population-based data. The objective was to assess the characteristics, medical management, and MRU of RW infants identified from national claims data. Infants aged from 6 to 24 months, receiving ≥2 dispensations of respiratory drugs within 3 months, and presenting a marker of poor control (index date), were selected. During the 6 months after index date, MRU was described in the cohort and among 3 subgroups with more severe RW, defined as ≥4 dispensations of respiratory drugs, ≥3 dispensations of oral corticosteroids (OCS), or ≥1 hospitalization for respiratory symptoms. A total of 115,489 infants had RW, corresponding to 8.2% of subjects in this age group. During follow-up, 68.7% of infants received inhaled corticosteroids, but only 1.8 U (unit) were dispensed over 6 months, suggesting discontinuous use. Control was mostly inadequate: 61.7% of subjects received OCS, 80.2% antibiotics, and 71.2% short-acting beta-agonists, and medical/paramedical visits were numerous, particularly for physiotherapy. Severe RW concerned 39.0% of the cohort; 32.8% and 11.7% of infants had repeated use of respiratory drugs and OCS, respectively, and 5.5% were hospitalized for respiratory symptoms. In this real-life nation-wide study, RW was common and infants had poor control and high MRU. Interventions are needed to support adequate use of controller therapy, and to improve medical care.

  5. Solderability Study of RABiTS-Based YBCO Coated Conductors

    SciTech Connect

    Zhang, Yifei; Duckworth, Robert C; Ha, Tam T; Gouge, Michael J

    2011-01-01

    The solderability of commercially available YBa{sub 2}Cu{sub 3}O{sub 7-x} (YBCO) coated conductors that were made from Rolling Assisted Biaxially Textured Substrates (RABiTS)-based templates was studied. The coated conductors, also known as second-generation (2G) high temperature superconductor (HTS) wires (in the geometry of flat tapes about 4 mm wide), were laminated with copper, brass, or stainless steel strips as stabilizers. To understand the factors that influence their solderability, surface profilometry and scanning electron microscopy were used to characterize the wire surfaces. The solderability of three solders, 52In48Sn, 67Bi33In, and 100In (wt.%), was evaluated using a standard test (IPC/ECA J-STD-002) and with two different commercial fluxes. It was found that the solderability varied with the solder and flux but the three different wires showed similar solderability for a fixed combination of solder and flux. Solder joints of the 2G wires were fabricated using the tools and the procedures recommended by the HTS wire manufacturer. The solder joints were made in a lap-joint geometry and with the superconducting sides of the two wires face-to-face. The electrical resistances of the solder joints were measured at 77 K, and the results were analyzed to qualify the soldering materials and evaluate the soldering process. It was concluded that although the selection of soldering materials affected the resistance of a solder joint, the resistivity of the stabilizer was the dominant factor.

  6. Increasing incidence of cataract surgery: Population-based study

    PubMed Central

    Gollogly, Heidrun E.; Hodge, David O.; St. Sauver, Jennifer L.; Erie, Jay C.

    2015-01-01

    PURPOSE To estimate the incidence of cataract surgery in a defined population and to determine longitudinal cataract surgery patterns. SETTING Mayo Clinic, Rochester, Minnesota, USA. DESIGN Cohort study. METHODS Rochester Epidemiology Project (REP) databases were used to identify all incident cataract surgeries in Olmsted County, Minnesota, between January 1, 2005, and December 31, 2011. Age-specific and sex-specific incidence rates were calculated and adjusted to the 2010 United States white population. Data were merged with previous REP data (1980 to 2004) to assess temporal trends in cataract surgery. Change in the incidence over time was assessed by fitting generalized linear models assuming a Poisson error structure. The probability of second-eye cataract surgery was calculated using the Kaplan-Meier method. RESULTS Included were 8012 cataract surgeries from 2005 through 2011. During this time, incident cataract surgery significantly increased (P < .001), peaking in 2011 with a rate of 1100 per 100 000 (95% confidence interval, 1050–1160). The probability of second-eye surgery 3, 12, and 24 months after first-eye surgery was 60%, 76%, and 86%, respectively, a significant increase compared with the same intervals in the previous 7 years (1998 to 2004) (P < .001). When merged with 1980 to 2004 REP data, incident cataract surgery steadily increased over the past 3 decades (P < .001). CONCLUSION Incident cataract surgery steadily increased over the past 32 years and has not leveled off, as reported in Swedish population-based series. Second-eye surgery was performed sooner and more frequently, with 60% of residents having second-eye surgery within 3-months of first-eye surgery. PMID:23820302

  7. Electrochemical studies of calcium chloride-based molten salt systems

    SciTech Connect

    Blanchard, Jr., Thomas P.

    1992-12-01

    Conductance and EMF studies of CaCl2-based melts were performed in the temperature range 790--990 C. Conductivity data collected using magnesia tubes and capillaries showed deviations from the data recommended by the National Bureau of Standards. These deviations are attributed to the slow dissolution of magnesia by the CaCl2-CaO melt. Conductivity data for molten CaCl2 using a pyrolytic boron nitride capillary were in reasonable agreement with the recommended data; however, undissolved CaO in CaCl2 may have caused blockage of the pyrolytic boron nitride capillary, resulting in fluctuations in the measured resistance. The utility of the AgCl/Ag reference electrode in CaCl2-AgCl and CaCl2-CaO-AgCl melts, using asbestos diaphragms and Vycor glass as reference half-cell membranes, was also investigated. Nernstian behavior was observed using both types of reference half-cell membranes in CaCl2-AgCl melts. The AgCl/Ag reference electrode also exhibited Nernstian behavior in CaCl2-CaO-AgCl melts using a Vycor reference half-cell membrane and a magnesia crucible. The use of CaCl2 as a solvent is of interest since it is used in plutonium metal purification, as well as various other commercial applications. 97 refs., 33 figs., 13 tabs.

  8. Dental Prophylaxis and Osteoradionecrosis: A Population-Based Study.

    PubMed

    Chang, C T; Liu, S P; Muo, C H; Tsai, C H; Huang, Y F

    2017-05-01

    The aim of this study was to investigate the association of different dental prophylactic modalities and osteoradionecrosis (ORN) and determine the risk of ORN under different timing periods of scaling, with the use chlorhexidine mouth rinse after surgery and with different strategies of fluoride gel application in head and neck cancer (HNC) participants. A cohort of 18,231 HNC participants, including 941 ORN patients and 17,290 matched control cases, were enrolled from a Longitudinal Health Insurance Database for Catastrophic Illness Patients (LHID-CIP) in Taiwan. Based on different dental prophylactic modalities before radiotherapy, including chlorhexidine mouth rinse, scaling, and fluoride gel, all HNC subjects were stratified into different groups. The Cox proportional hazard regression was used to compare ORN incidences under different dental prophylactic modalities. The results revealed that scaling and chlorhexidine mouth rinse were significantly related to ORN risk ( P = 0.004 and P < 0.0001). Chlorhexidine mouth rinse was highly correlated to ORN occurrence (hazard ratio [HR], 1.83-2.66), as exposure increased the risk by 2.43-fold among oral cancer patients, regardless of whether they had received major oral surgery or not. Oral cancer patients receiving scaling within 2 wk before radiotherapy increased their incidence of ORN by 1.28-fold compared with patients who had not undergone scaling within 6 mo. There is no significance of fluoride application for dental prophylaxis in increasing ORN occurrence. In conclusion, dental prophylaxis before radiotherapy is strongly correlated to ORN in HNC patients. Chlorhexidine exposure and dental scaling within 2 wk before radiotherapy is significantly related to ORN risk, especially in oral cancer patients. The use of 1.1% NaF topical application did not significantly increase the risk of ORN in HNC patients. An optimal dental prophylaxis protocol to reduce ORN should concern cancer location, cautious prescription

  9. Longitudinal study of alcohol consumption and HDL concentrations: a community-based study.

    PubMed

    Huang, Shue; Li, Junjuan; Shearer, Gregory C; Lichtenstein, Alice H; Zheng, Xiaoming; Wu, Yuntao; Jin, Cheng; Wu, Shouling; Gao, Xiang

    2017-04-01

    Background: In cross-sectional studies and short-term clinical trials, it has been suggested that there is a positive dose-response relation between alcohol consumption and HDL concentrations. However, prospective data have been limited.Objective: We sought to determine the association between total alcohol intake, the type of alcohol-containing beverage, and the 6-y (2006-2012) longitudinal change in HDL-cholesterol concentrations in a community-based cohort.Design: A total of 71,379 Chinese adults (mean age: 50 y) who were free of cardiovascular diseases and cancer and did not use cholesterol-lowering agents during follow-up were included in the study. Alcohol intake was assessed via a questionnaire in 2006 (baseline), and participants were classified into the following categories of alcohol consumption: never, past, light (women: 0-0.4 servings/d; men: 0-0.9 servings/d), moderate (women: 0.5-1.0 servings/d; men: 1-2 servings/d), and heavy (women: >1.0 servings/d; men: >2 servings/d). HDL-cholesterol concentrations were measured in 2006, 2008, 2010, and 2012. We used generalized estimating equation models to examine the associations between baseline alcohol intake and the change in HDL-cholesterol concentrations with adjustment for age, sex, smoking, physical activity, obesity, hypertension, diabetes, liver function, and C-reactive protein concentrations.Results: An umbrella-shaped association was observed between total alcohol consumption and changes in HDL-cholesterol concentrations. Compared with never drinkers, past, light, moderate, and heavy drinkers experienced slower decreases in HDL cholesterol of 0.012 mmol · L(-1) · y(-1) (95% CI: 0.008, 0.016 mmol · L(-1) · y(-1)), 0.013 mmol · L(-1) · y(-1) (95% CI: 0.010, 0.016 mmol · L(-1) · y(-1)), 0.017 mmol · L(-1) · y(-1) (95% CI: 0.009, 0.025 mmol · L(-1) · y(-1)), and 0.008 mmol · L(-1) · y(-1) (95% CI: 0.005, 0.011 mmol · L(-1) · y(-1)), respectively (P < 0.0001 for all), after adjustment for

  10. A Ground-Based Research Vehicle for Base Drag Studies at Subsonic Speeds

    NASA Technical Reports Server (NTRS)

    Diebler, Corey; Smith, Mark

    2002-01-01

    A ground research vehicle (GRV) has been developed to study the base drag on large-scale vehicles at subsonic speeds. Existing models suggest that base drag is dependent upon vehicle forebody drag, and for certain configurations, the total drag of a vehicle can be reduced by increasing its forebody drag. Although these models work well for small projectile shapes, studies have shown that they do not provide accurate predictions when applied to large-scale vehicles. Experiments are underway at the NASA Dryden Flight Research Center to collect data at Reynolds numbers to a maximum of 3 x 10(exp 7), and to formulate a new model for predicting the base drag of trucks, buses, motor homes, reentry vehicles, and other large-scale vehicles. Preliminary tests have shown errors as great as 70 percent compared to Hoerner's two-dimensional base drag prediction. This report describes the GRV and its capabilities, details the studies currently underway at NASA Dryden, and presents preliminary results of both the effort to formulate a new base drag model and the investigation into a method of reducing total drag by manipulating forebody drag.

  11. The "Reverse Case Study:" Enhancing Creativity in Case-Based Instruction in Leadership Studies

    ERIC Educational Resources Information Center

    Atkinson, Timothy N.

    2014-01-01

    In this application brief I share a case study assignment I used in my "Leadership in Complex Organizations" classes to promote creativity in problem solving. I sorted Ph.D. students into two teams and trained them to use creative writing techniques to "encode" theory into their own cases. A sense of competition emerged. Later,…

  12. A School-Based Study on Situational Interest of Investigative Study in Senior Physics

    ERIC Educational Resources Information Center

    Leung, Yat-yin

    2015-01-01

    This paper reports the findings from the interview data of a research aiming at studying how to trigger students' situational interest in physics and its implications on learning and teaching in the New Senior Secondary (NSS) physics curriculum. 49 students from a boys' school were invited to write one to three learning experiences in physics that…

  13. A School-Based Study on Situational Interest of Investigative Study in Senior Physics

    ERIC Educational Resources Information Center

    Leung, Yat-yin

    2015-01-01

    This paper reports the findings from the interview data of a research aiming at studying how to trigger students' situational interest in physics and its implications on learning and teaching in the New Senior Secondary (NSS) physics curriculum. 49 students from a boys' school were invited to write one to three learning experiences in physics that…

  14. Competence-Based System Self-Study System for Suggesting Study Materials Links

    ERIC Educational Resources Information Center

    Nitchot, Athitaya; Gilbert, Lester; Wills, Gary B.

    2014-01-01

    The article proposes a self-study system which suggests web links to learners. The suggestions depend upon the learner's chosen competences selected from a competence structure for a particular knowledge domain. Three experiments were conducted, where the first compared the perceived usefulness and value of the links generated by different…

  15. Competence-Based System Self-Study System for Suggesting Study Materials Links

    ERIC Educational Resources Information Center

    Nitchot, Athitaya; Gilbert, Lester; Wills, Gary B.

    2014-01-01

    The article proposes a self-study system which suggests web links to learners. The suggestions depend upon the learner's chosen competences selected from a competence structure for a particular knowledge domain. Three experiments were conducted, where the first compared the perceived usefulness and value of the links generated by different…

  16. A study on the cytotoxicity of carbon-based materials.

    PubMed

    Saha, Dipendu; Heldt, Caryn L; Gencoglu, Maria F; Vijayaragavan, K Saagar; Chen, Jihua; Saksule, Ashish

    2016-11-01

    With an aim to understand the origin and key contributing factors towards carbon-induced cytotoxicity, we have studied five different carbon samples with diverse surface area, pore width, shape and size, conductivity and surface functionality. All the carbon materials were characterized with surface area and pore size distribution, X-ray photoelectron spectroscopy (XPS) and electron microscopic imaging. We performed cytotoxicity study in Caco-2 cells by colorimetric assay, oxidative stress analysis by reactive oxygen species (ROS) detection, cellular metabolic activity measurement by adenosine triphosphate (ATP) depletion and visualization of cellular internalization by TEM imaging. The carbon materials demonstrated a varying degree of cytotoxicity in contact with Caco-2 cells. The lowest cell survival rate was observed for nanographene, which possessed the minimal size amongst all the carbon samples under this study. None of the carbons induced oxidative stress to the cells as indicated by the ROS generation results. Cellular metabolic activity study revealed that the carbon materials caused ATP depletion in cells and nanographene caused the highest depletion. Visual observation by TEM imaging indicated the cellular internalization of nanographene. This study confirmed that the size is the key cause of carbon-induced cytotoxicity and it is probably caused by the ATP depletion within the cell. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Hypertension in Pregnancy: A Community-Based Study

    PubMed Central

    Mehta, Bharti; Kumar, Vijay; Chawla, Sumit; Sachdeva, Sandeep; Mahopatra, Debjyoti

    2015-01-01

    Background: Hypertensive disorders during pregnancy occur in women with preexisting primary or secondary chronic hypertension, and in women who develop new-onset hypertension in the second half of pregnancy. The present study was undertaken to study the prevalence and correlates of hypertension in pregnancy in a rural block of Haryana. Materials and Methods: This cross-sectional study was carried out in the all 20 subcenters under Community Health Center (CHC) Chiri, Block Lakhanmajra. All the pregnant women registered at the particular subcenter at a point of time of visit were included in the study. Appropriate statistical tests were used for analysis. Results: A total of 931 pregnant women were included in the present study. Prevalence of hypertension in pregnancy was found to be 6.9%. Maternal age ≥25 years, gestational period ≤20 weeks, history of cesarean section, history of preterm delivery, and history of hypertension in previous pregnancy were found to be significantly associated with prevalence of hypertension in pregnancy. Conclusion: Nearly one in 14 pregnant women in rural areas of Haryana suffers from a hypertensive disorder of pregnancy. Early diagnosis and treatment through regular antenatal checkup is a key factor to prevent hypertensive disorders of pregnancy and its complications. PMID:26435602

  18. Aeroelastic Optimization Study Based on the X-56A Model

    NASA Technical Reports Server (NTRS)

    Li, Wesley W.; Pak, Chan-Gi

    2014-01-01

    One way to increase the aircraft fuel efficiency is to reduce structural weight while maintaining adequate structural airworthiness, both statically and aeroelastically. A design process which incorporates the object-oriented multidisciplinary design, analysis, and optimization (MDAO) tool and the aeroelastic effects of high fidelity finite element models to characterize the design space was successfully developed and established. This paper presents two multidisciplinary design optimization studies using an object-oriented MDAO tool developed at NASA Armstrong Flight Research Center. The first study demonstrates the use of aeroelastic tailoring concepts to minimize the structural weight while meeting the design requirements including strength, buckling, and flutter. Such an approach exploits the anisotropic capabilities of the fiber composite materials chosen for this analytical exercise with ply stacking sequence. A hybrid and discretization optimization approach improves accuracy and computational efficiency of a global optimization algorithm. The second study presents a flutter mass balancing optimization study for the fabricated flexible wing of the X-56A model since a desired flutter speed band is required for the active flutter suppression demonstration during flight testing. The results of the second study provide guidance to modify the wing design and move the design flutter speeds back into the flight envelope so that the original objective of X-56A flight test can be accomplished successfully. The second case also demonstrates that the object-oriented MDAO tool can handle multiple analytical configurations in a single optimization run.

  19. Studies of zeolite-based artificial photosynthetic systems

    NASA Astrophysics Data System (ADS)

    Zhang, Haoyu

    Y were obtained. The Ru complexes were anchored on the surface of zeolites via ion-exchange or "ship-in-bottle" synthesis. The spectroscopic properties of the NanoY-entrapped species including methyl viologen (MV2+), RuL were measured via transmission techniques. The zeolite-encapsulated species were found to have red-shift absorption and emission bands and longer MLCT life times. By incorporating both donors Ru complexes and acceptors MV2+ in NanoY, electron transfer kinetics was examined. LFP study showed a slower back-electron-transfer rate as compared to forward electron transfer. Photochemically generated long-lived charge separation is the key step in processes that aim for conversion of solar energy into chemical energy. We incorporated RuL complex on the surface of a pinhole-free zeolite membrane by quaternization of L and surrounded with intrazeolitic bipyridinium ions (N,N'-trimethyl-2,2'-bipyridinium ion, 3DQ2+). Visible-light irradiation of the Ru complex side of the membrane in the presence of a sacrificial electron donor led to formation of PVS-· on the other side. Pore-blocking disilazane-based chemistry allows for Na+ to migrate through the membrane to maintain charge balance, while keeping the 3DQ2+ entrapped in the zeolite. These results provided encouragement that the zeolite membrane based architecture has the necessary features for not only incorporating molecular assemblies with long-lived charge separation but also for ready exploitation of the spatially separated charges to store visible light energy in chemical species. The pore-narrowing strategy applied under mild conditions can be used in control-release of active substances such as drug, pesticides, and herbicides. Methyl viologen (MV2+) was chosen as the guest molecule, since it is widely used as an herbicide and its release is of interest in agricultural applications. To explore the controlled-release capability of the surface-modified zeolite, MV2+-encapsulated zeolite Y particles were

  20. Experimental and trial-based study of Resilient Packet Ring

    NASA Astrophysics Data System (ADS)

    Ramnath, Vasudha; Cheng, Heng Seng; Ngoh, Lek Heng

    2002-08-01

    An experimental study of the Resilient Packet Ring (RPR) media access control (MAC) technology that is optimized for IP traffic in the metropolitan-area-network (MAN) environment is described. The study involved the deployment and trials of a RPR testbed encompassing a public optical fiber infrastructure in which Cisco Systems' Dynamic Packet Transport (DPT) Ring Technology - a prestandard RPR implementation - was used. We focus on a number of important RPR protocol features that are vital to the future success of RPR as a MAN/wide-area-network (WAN) network technology. Related research on RPR/DPT has been done so far through simulation studies only. Standardization of RPR is currently being performed by the Institute of Electrical and Electronics Engineers (IEEE) 802.17 working group and is expected to be completed in 2003. Also, we present and discuss the experiments and tests performed to investigate the key features of RPR, along with the results obtained.

  1. Ecotoxicity of biocomposites based on renewable feedstock - preliminary studies.

    PubMed

    Rudnik, E; Milanov, N; Matuschek, G; Kettrup, A

    2007-12-01

    The aim of the work was to study the biodegradation process of biocomposites prepared from renewable resources and the ecotoxicological assessment of their biodegradation products. Biocomposites from modified starch reinforced with various cellulose fibers were prepared by the extrusion process. Biodegradation studies were carried out according to the ISO respirometic method. Ecotoxicity of biodegradation products was assessed by the luminescent bacteria test. It was found that biodegradation of biocomposites was above 60% within 24 days according to the results of respirometric test. Increase in the amount of natural fiber reinforcement, as well as smaller fiber size increased the biodegradability of biocomposites. On the basis of the preliminary results of the ecotoxicological test using luminescent bacteria it seems that the biodegradation products of the biocomposites studied are ecologically safe.

  2. Familial risk of epilepsy: a population-based study

    PubMed Central

    Peljto, Anna L.; Barker-Cummings, Christie; Vasoli, Vincent M.; Leibson, Cynthia L.; Hauser, W. Allen; Buchhalter, Jeffrey R.

    2014-01-01

    Almost all previous studies of familial risk of epilepsy have had potentially serious methodological limitations. Our goal was to address these limitations and provide more rigorous estimates of familial risk in a population-based study. We used the unique resources of the Rochester Epidemiology Project to identify all 660 Rochester, Minnesota residents born in 1920 or later with incidence of epilepsy from 1935–94 (probands) and their 2439 first-degree relatives who resided in Olmsted County. We assessed incidence of epilepsy in relatives by comprehensive review of the relatives’ medical records, and estimated age-specific cumulative incidence and standardized incidence ratios for epilepsy in relatives compared with the general population, according to proband and relative characteristics. Among relatives of all probands, cumulative incidence of epilepsy to age 40 was 4.7%, and risk was increased 3.3-fold (95% confidence interval 2.75–5.99) compared with population incidence. Risk was increased to the greatest extent in relatives of probands with idiopathic generalized epilepsies (standardized incidence ratio 6.0) and epilepsies associated with intellectual or motor disability presumed present from birth, which we denoted ‘prenatal/developmental cause’ (standardized incidence ratio 4.3). Among relatives of probands with epilepsy without identified cause (including epilepsies classified as ‘idiopathic’ or ‘unknown cause’), risk was significantly increased for epilepsy of prenatal/developmental cause (standardized incidence ratio 4.1). Similarly, among relatives of probands with prenatal/developmental cause, risk was significantly increased for epilepsies without identified cause (standardized incidence ratio 3.8). In relatives of probands with generalized epilepsy, standardized incidence ratios were 8.3 (95% confidence interval 2.93–15.31) for generalized epilepsy and 2.5 (95% confidence interval 0.92–4.00) for focal epilepsy. In relatives of

  3. Prevalence of microcephaly in Europe: population based study.

    PubMed

    Morris, Joan K; Rankin, Judith; Garne, Ester; Loane, Maria; Greenlees, Ruth; Addor, Marie-Claude; Arriola, Larraitz; Barisic, Ingeborg; Bergman, Jorieke E H; Csaky-Szunyogh, Melinda; Dias, Carlos; Draper, Elizabeth S; Gatt, Miriam; Khoshnood, Babak; Klungsoyr, Kari; Kurinczuk, Jennifer J; Lynch, Catherine; McDonnell, Robert; Nelen, Vera; Neville, Amanda J; O'Mahony, Mary T; Pierini, Anna; Randrianaivo, Hanitra; Rissmann, Anke; Tucker, David; Verellen-Dumoulin, Christine; de Walle, Hermien E K; Wellesley, Diana; Wiesel, Awi; Dolk, Helen

    2016-09-13

     To provide contemporary estimates of the prevalence of microcephaly in Europe, determine if the diagnosis of microcephaly is consistent across Europe, and evaluate whether changes in prevalence would be detected using the current European surveillance performed by EUROCAT (the European Surveillance of Congenital Anomalies).  Questionnaire and population based observational study.  24 EUROCAT registries covering 570 000 births annually in 15 countries.  Cases of microcephaly not associated with a genetic condition among live births, fetal deaths from 20 weeks' gestation, and terminations of pregnancy for fetal anomaly at any gestation.  Prevalence of microcephaly (1 Jan 2003-31 Dec 2012) analysed with random effects Poisson regression models to account for heterogeneity across registries.  16 registries responded to the questionnaire, of which 44% (7/16) used the EUROCAT definition of microcephaly (a reduction in the size of the brain with a skull circumference more than 3 SD below the mean for sex, age, and ethnic origin), 19% (3/16) used a 2 SD cut off, 31% (5/16) were reliant on the criteria used by individual clinicians, and one changed criteria between 2003 and 2012. Prevalence of microcephaly in Europe was 1.53 (95% confidence interval 1.16 to 1.96) per 10 000 births, with registries varying from 0.4 (0.2 to 0.7) to 4.3 (3.6 to 5.0) per 10 000 (χ(2)=338, df=23, I(2)=93%). Registries with a 3 SD cut off reported a prevalence of 1.74 per 10 000 (0.86 to 2.93) compared with those with the less stringent 2 SD cut off of 1.21 per 10 000 (0.21 to 2.93). The prevalence of microcephaly would need to increase in one year by over 35% in Europe or by over 300% in a single registry to reach statistical significance (P<0.01).  EUROCAT could detect increases in the prevalence of microcephaly from the Zika virus of a similar magnitude to those observed in Brazil. Because of the rarity of microcephaly and discrepant diagnostic criteria, however, the smaller

  4. Prevalence of microcephaly in Europe: population based study

    PubMed Central

    Rankin, Judith; Garne, Ester; Loane, Maria; Greenlees, Ruth; Addor, Marie-Claude; Arriola, Larraitz; Barisic, Ingeborg; Bergman, Jorieke E H; Csaky-Szunyogh, Melinda; Dias, Carlos; Draper, Elizabeth S; Gatt, Miriam; Khoshnood, Babak; Klungsoyr, Kari; Kurinczuk, Jennifer J; Lynch, Catherine; McDonnell, Robert; Nelen, Vera; Neville, Amanda J; O’Mahony, Mary T; Pierini, Anna; Randrianaivo, Hanitra; Rissmann, Anke; Tucker, David; Verellen-Dumoulin, Christine; de Walle, Hermien E K; Wellesley, Diana; Wiesel, Awi; Dolk, Helen

    2016-01-01

    Objectives To provide contemporary estimates of the prevalence of microcephaly in Europe, determine if the diagnosis of microcephaly is consistent across Europe, and evaluate whether changes in prevalence would be detected using the current European surveillance performed by EUROCAT (the European Surveillance of Congenital Anomalies). Design Questionnaire and population based observational study. Setting 24 EUROCAT registries covering 570 000 births annually in 15 countries. Participants Cases of microcephaly not associated with a genetic condition among live births, fetal deaths from 20 weeks’ gestation, and terminations of pregnancy for fetal anomaly at any gestation. Main outcome measures Prevalence of microcephaly (1 Jan 2003-31 Dec 2012) analysed with random effects Poisson regression models to account for heterogeneity across registries. Results 16 registries responded to the questionnaire, of which 44% (7/16) used the EUROCAT definition of microcephaly (a reduction in the size of the brain with a skull circumference more than 3 SD below the mean for sex, age, and ethnic origin), 19% (3/16) used a 2 SD cut off, 31% (5/16) were reliant on the criteria used by individual clinicians, and one changed criteria between 2003 and 2012. Prevalence of microcephaly in Europe was 1.53 (95% confidence interval 1.16 to 1.96) per 10 000 births, with registries varying from 0.4 (0.2 to 0.7) to 4.3 (3.6 to 5.0) per 10 000 (χ2=338, df=23, I2=93%). Registries with a 3 SD cut off reported a prevalence of 1.74 per 10 000 (0.86 to 2.93) compared with those with the less stringent 2 SD cut off of 1.21 per 10 000 (0.21 to 2.93). The prevalence of microcephaly would need to increase in one year by over 35% in Europe or by over 300% in a single registry to reach statistical significance (P<0.01). Conclusions EUROCAT could detect increases in the prevalence of microcephaly from the Zika virus of a similar magnitude to those observed in Brazil. Because of the rarity

  5. INTEGRATED GENOME-BASED STUDIES OF SHEWANELLA ECOPHYSIOLOGY

    SciTech Connect

    NEALSON, KENNETH H.

    2013-10-15

    laboratories. Applications: 1. Corrosion: Electron flow is often part of the corrosive process, and several studies were done in concert with this proposal with regard to the ability of EET-capable bacteria to enhance, inhibit, or detect corrosion. These included using EET-capable bacteria to detect corrosion in its earliest stages [5], to use corrosion-causing bacteria for the study of the microbe/mineral interface during corrosion [1], and to study the groups of microbes involved with corrosion of natural systems [19]. 2. Bioenergy and microbial fuel cells: The production of electricity by Shewanella was shown early in this program (several years ago) to be dependent on the genes for extracellular electron transport (EET), and applied work involved the testing of various strains and conditions for the optimization of current production by the shewanellae [11,14,16]. 3. Identification of shewanellae strains: Based on similarities seen in genomic comparisons, a rapid method was employed for distinguishing between shewanellae strains [17]. Interactions with other laboratories: This grant was an extension of a grant involving the so-called ?Shewanella Federation?, and as such, a number of our publications were joint with other members of this group. The groups included: 1. Pacific Northwest Laboratories ? 2. Oak Ridge National Labs 3. Michigan State University 4. University of Oklahoma 5. Naval Research Laboratory, Washington DC 6. Burnham Medical Research Institute, San Diego 7. J. Craig Venter Institute, San Diego Education: Graduate Students: Michael Waters, Ph.D. ? at NIST, Washington D.C. Lewis Hsu, Ph.D. ? at NRL, San Diego Howard Harris, Ph.D. ? Postdoc at University, France Everett Salas, Ph.D. ? Scientist at Chevron McLean, Jeffrey, Ph.D. ? Scientist at J. Craig Venter Institute McCrow, John, Ph.D. ? Scientist at J. Craig Venter Institute Postdocs: Mohamed El-Naggar ? Professor of Physics, USC Jinjun Kan ? Senior Researcher at Undergraduatges: During this year, we had

  6. Data book: Space station/base food system study. Book 3: Study selection rationale sheets

    NASA Technical Reports Server (NTRS)

    1970-01-01

    The supporting rationale sheets are presented which were utilized in the selection and support of the concepts considered in the final phase of the study. Each concept, conceived to fulfill a specific function of the food system, was assessed in terms of the eight critical factors depicted on the rationale sheet. When weighted and totaled, the resulting selection factor was used as a guide in making the final decision.

  7. Consensus on the Definition of Advanced Parkinson's Disease: A Neurologists-Based Delphi Study (CEPA Study)

    PubMed Central

    Kulisevsky, Jaime; Tolosa, Eduardo S.

    2017-01-01

    To date, no consensus exists on the key factors for diagnosing advanced Parkinson disease (APD). To obtain consensus on the definition of APD, we performed a prospective, multicenter, Spanish nationwide, 3-round Delphi study (CEPA study). An ad hoc questionnaire was designed with 33 questions concerning the relevance of several clinical features for APD diagnosis. In the first-round, 240 neurologists of the Spanish Movement Disorders Group participated in the study. The results obtained were incorporated into the questionnaire and both, results and questionnaire, were sent out to and fulfilled by 26 experts in Movement Disorders. Review of results from the second-round led to a classification of symptoms as indicative of “definitive,” “probable,” and “possible” APD. This classification was confirmed by 149 previous participating neurologists in a third-round, where 92% completely or very much agreed with the classification. Definitive symptoms of APD included disability requiring help for the activities of daily living, presence of motor fluctuations with limitations to perform basic activities of daily living without help, severe dysphagia, recurrent falls, and dementia. These results will help neurologists to identify some key factors in APD diagnosis, thus allowing users to categorize the patients for a homogeneous recognition of this condition. PMID:28239501

  8. Consensus on the Definition of Advanced Parkinson's Disease: A Neurologists-Based Delphi Study (CEPA Study).

    PubMed

    Luquin, Maria-Rosario; Kulisevsky, Jaime; Martinez-Martin, Pablo; Mir, Pablo; Tolosa, Eduardo S

    2017-01-01

    To date, no consensus exists on the key factors for diagnosing advanced Parkinson disease (APD). To obtain consensus on the definition of APD, we performed a prospective, multicenter, Spanish nationwide, 3-round Delphi study (CEPA study). An ad hoc questionnaire was designed with 33 questions concerning the relevance of several clinical features for APD diagnosis. In the first-round, 240 neurologists of the Spanish Movement Disorders Group participated in the study. The results obtained were incorporated into the questionnaire and both, results and questionnaire, were sent out to and fulfilled by 26 experts in Movement Disorders. Review of results from the second-round led to a classification of symptoms as indicative of "definitive," "probable," and "possible" APD. This classification was confirmed by 149 previous participating neurologists in a third-round, where 92% completely or very much agreed with the classification. Definitive symptoms of APD included disability requiring help for the activities of daily living, presence of motor fluctuations with limitations to perform basic activities of daily living without help, severe dysphagia, recurrent falls, and dementia. These results will help neurologists to identify some key factors in APD diagnosis, thus allowing users to categorize the patients for a homogeneous recognition of this condition.

  9. Postmarketing Safety Study Tool: A Web Based, Dynamic, and Interoperable System for Postmarketing Drug Surveillance Studies

    PubMed Central

    Sinaci, A. Anil; Laleci Erturkmen, Gokce B.; Gonul, Suat; Yuksel, Mustafa; Invernizzi, Paolo; Thakrar, Bharat; Pacaci, Anil; Cinar, H. Alper; Cicekli, Nihan Kesim

    2015-01-01

    Postmarketing drug surveillance is a crucial aspect of the clinical research activities in pharmacovigilance and pharmacoepidemiology. Successful utilization of available Electronic Health Record (EHR) data can complement and strengthen postmarketing safety studies. In terms of the secondary use of EHRs, access and analysis of patient data across different domains are a critical factor; we address this data interoperability problem between EHR systems and clinical research systems in this paper. We demonstrate that this problem can be solved in an upper level with the use of common data elements in a standardized fashion so that clinical researchers can work with different EHR systems independently of the underlying information model. Postmarketing Safety Study Tool lets the clinical researchers extract data from different EHR systems by designing data collection set schemas through common data elements. The tool interacts with a semantic metadata registry through IHE data element exchange profile. Postmarketing Safety Study Tool and its supporting components have been implemented and deployed on the central data warehouse of the Lombardy region, Italy, which contains anonymized records of about 16 million patients with over 10-year longitudinal data on average. Clinical researchers in Roche validate the tool with real life use cases. PMID:26543873

  10. Feasibility study of algae-based CO2 capture

    EPA Science Inventory

    Abstract: The biomass of microalgae contains approximately 50% carbon, which is commonly obtained from the atmosphere, but can also be taken from commercial sources that produce CO2, such as coal-fired power plants. A study of operational demonstration projects is being underta...

  11. Feasibility study of algae-based CO2 capture

    EPA Science Inventory

    The biomass of microalgae contains approximately 50% carbon, which is commonly obtained from the atmosphere, but can also be taken from commercial sources that produce CO2, such as coal-fired power plants. A study of operational demonstration projects is being undertaken to eval...

  12. Feasibility study of algae-based CO2 capture

    EPA Science Inventory

    Abstract: The biomass of microalgae contains approximately 50% carbon, which is commonly obtained from the atmosphere, but can also be taken from commercial sources that produce CO2, such as coal-fired power plants. A study of operational demonstration projects is being underta...

  13. A Study of Teacher Effects Based on Students' Achievement Scores.

    ERIC Educational Resources Information Center

    Acland, Henry

    This report tests the assumption that teachers have an impact on how much students learn. The results of this study indicate that teachers have an effect on average class achievement scores, and that this effect can be broken down into a stable component attributed to the teachers' consistency, and an unstable effect which varies from year to…

  14. Feasibility study of algae-based Carbon Dioxide capture

    EPA Science Inventory

    SUMMARY: The biomass of microalgae contains approximately 50% carbon, which is commonly obtained from the atmosphere, but can also be taken from commercial sources that produce CO2, such as coal-fired power plants. A study of operational demonstration projects is being undertak...

  15. Feasibility study of algae-based Carbon Dioxide capture

    EPA Science Inventory

    SUMMARY: The biomass of microalgae contains approximately 50% carbon, which is commonly obtained from the atmosphere, but can also be taken from commercial sources that produce CO2, such as coal-fired power plants. A study of operational demonstration projects is being undertak...

  16. A Study of Multimedia Application-Based Vocabulary Acquisition

    ERIC Educational Resources Information Center

    Shao, Jing

    2012-01-01

    The development of computer-assisted language learning (CALL) has created the opportunity for exploring the effects of the multimedia application on foreign language vocabulary acquisition in recent years. This study provides an overview the computer-assisted language learning (CALL) and detailed a developing result of CALL--multimedia. With the…

  17. Hypothyroidism and Lipid Levels in a Community Based Study (TTS).

    PubMed

    Alamdari, Shahram; Amouzegar, Atieh; Tohidi, Maryam; Gharibzadeh, Safoora; Kheirkhah, Pouyan; Kheirkhah, Parnian; Azizi, Fereidoun

    2016-01-01

    Thyroid hormones play an important role in lipid metabolism. Overt hypothyroidism is known to be associated with increased lipid profiles, but the effect of subclinical hypothyroidism (SCH) on lipid profile remains controversial. The aim of this study was to assess the association between thyroid disorders and serum lipid levels. The present study was conducted within the framework of Tehran lipid and glucose study (TLGS). Serum concentrations of TSH and FT4, cholesterol, triglycerides and HDL-C were measured in 5786 randomly selected subjects. Serum LDL was calculated according to the Friedwald formula. The study assessed 5154 subjects including 42.5% males and 57.5% females, with a mean age of 39.71 ± 14.2 years (ranged 20 - 90 years). Serum cholesterol was significantly higher in overt hypothyroidism in comparison to subclinical hypothyroidism (P = 0.003). Serum cholesterol, HDL -C, LDL-C and TG did not differ between subclinical hypothyroid and control groups. Among euthyroid men, serum FT4 levels were inversely correlated with serum cholesterol and TG. In euthyroid women, serum FT4 levels were correlated positively with serum HDL-C and negatively correlated with TG and TG/HDL-C ratio and TSH levels were associated negatively with, HDL-C. No differences existed in lipid profiles between subclinical hypothyroidism and euthyroid subjects. There are correlations between serum FT4 and TSH and lipid profiles.

  18. Telecommunication: Economic studies. Citations from the NTIS data base

    NASA Astrophysics Data System (ADS)

    Reed, W. E.

    1980-06-01

    Research on economic evaluations of the telecommunications industry is cited. Communication satellites, common carriers, cable television, telephone systems, and television systems are all covered in the bibliography. Economic studies of the foreign telecommunications industry are included. This updated bibliography contains 60 abstracts, 36 of which are new entries to the previous edition.

  19. Telecommunication: Economic studies. Citations from the NTIS data base

    NASA Astrophysics Data System (ADS)

    Reed, W. E.

    1980-06-01

    Research on economic evaluations of the telecommunications industry is cited. Communication satellites, common carriers, cable television, telephones systems, and television systems are all covered in the bibliography. Economic studies of the foreign telecommunications industry are included. This updated bibliography contains 280 abstracts, none of which are new entries to the previous edition.

  20. Characterizing Adolescent Prescription Misusers: A Population-Based Study

    ERIC Educational Resources Information Center

    Schepis, Ty S.; Krishnan-Sarin, Suchitra

    2008-01-01

    A study was conducted to investigate the risk factors associated with the abuse of opiods, stimulants, tranquilizers and other sedatives among adolescents aged between 12 to 17 years and the presence of one more symptoms of a substance use disorder from prescription misuse. Results indicated that poor academic performance; enjoyment of…

  1. A Satellite Based Fog Study of the Korean Peninsula

    DTIC Science & Technology

    2007-06-01

    worksheets (see an example in Figure 8), which were excel spreadsheets formatted as a guideline used by forecasters when preparing their terminal...of the forecasts worksheets used by forecasters attached to the 607th Weather Squadron, Korea...accuracy was considered questionable by some meteorologists. The Kim and Lee (1970) study created a worksheet with the number of mean fog days per month

  2. A Study on Improving Information Processing Abilities Based on PBL

    ERIC Educational Resources Information Center

    Kim, Du Gyu; Lee, JaeMu

    2014-01-01

    This study examined an instruction method for the improvement of information processing abilities in elementary school students. Current elementary students are required to develop information processing abilities to create new knowledge for this digital age. There is, however, a shortage of instruction strategies for these information processing…

  3. Thesaurus-Based Automatic Indexing: A Study of Indexing Failure.

    ERIC Educational Resources Information Center

    Caplan, Priscilla Louise

    This study examines automatic indexing performed with a manually constructed thesaurus on a document collection of titles and abstracts of library science master's papers. Errors are identified when the meaning of a posted descriptor, as identified by context in the thesaurus, does not match that of the passage of text which occasioned the…

  4. Developing a CEF Based Curriculum: A Case Study

    ERIC Educational Resources Information Center

    Ustunluoglu, Evrim; Zazaoglu, Kismet Funda Akgul; Keskin, Michelle N.; Saraykoylu, Beril; Akdogan, Gulfem

    2012-01-01

    The common purposes of the studies conducted in language program evaluations are to examine the match between what is desired for the programme versus the actual state of the programme, to make judgments about learners' level of skills and knowledge, and to make suggestions for improvement. However, it is not currently common practice in Turkey…

  5. Coke forming reaction kinetic study on petroleum based feeds

    SciTech Connect

    Shigley, J.K.; Fu, Ta-Wei

    1988-08-01

    The carbonization of hydrocarbons is a very complex process. The pyrolysis reactions are predominantly free radical in nature and can be summarized as a polymerization process. The phase transitions from a 199% isotropic phase to an anisotropic mesophase during the carbonization of many feeds is an important and much studied phenomena. This phenomena is capitalized on in industry to produce needle or graphite coke. The kinetics of pitch polymerization and coke formation have historically been studied by measuring the solubility of the heat treated material in various solvents. The concentration of free radicals in the carbonized samples have also been used to investigate the mechanistic and kinetic aspects of the process. A very extensive study was conducted by Greinke using GPC techniques to measure the changes in narrow molecular weight ranges and the overall molecular weight distribution of a pitch during carbonization. This study focuses on the use of product volatile matter as the measure of extent of carbonization of two different feedstocks. It is ideally suited for use in commercial coking operations as a control or quality parameter of green coke.

  6. Thesaurus-Based Automatic Indexing: A Study of Indexing Failure.

    ERIC Educational Resources Information Center

    Caplan, Priscilla Louise

    This study examines automatic indexing performed with a manually constructed thesaurus on a document collection of titles and abstracts of library science master's papers. Errors are identified when the meaning of a posted descriptor, as identified by context in the thesaurus, does not match that of the passage of text which occasioned the…

  7. Case Study 4: Using Game-Based Learning for Induction

    ERIC Educational Resources Information Center

    Javaid, Osman

    2017-01-01

    This case study tracks the development of a digital induction resource implementing game elements that focuses on the first two stages of Gilly Salmon's Five Stage Model, namely "access and motivation" and "online socialisation" (Salmon, 2011). In the summer of 2016, a prototype was developed and presented at the Playful…

  8. Insect-Based Vision for Autonomous Vehicles: A Feasibility Study

    NASA Technical Reports Server (NTRS)

    Srinivasan, Mandyam V.

    1999-01-01

    The aims of the project were to use a high-speed digital video camera to pursue two questions: (1) To explore the influence of temporal imaging constraints on the performance of vision systems for autonomous mobile robots; (2) To study the fine structure of insect flight trajectories in order to better understand the characteristics of flight control, orientation and navigation.

  9. Insect-Based Vision for Autonomous Vehicles: A Feasibility Study

    NASA Technical Reports Server (NTRS)

    Srinivasan, Mandyam V.

    1999-01-01

    The aims of the project were to use a high-speed digital video camera to pursue two questions: i) To explore the influence of temporal imaging constraints on the performance of vision systems for autonomous mobile robots; To study the fine structure of insect flight trajectories with in order to better understand the characteristics of flight control, orientation and navigation.

  10. Insect-Based Vision for Autonomous Vehicles: A Feasibility Study

    NASA Technical Reports Server (NTRS)

    Srinivasan, Mandyam V.

    1999-01-01

    The aims of the project were to use a high-speed digital video camera to pursue two questions: (1) To explore the influence of temporal imaging constraints on the performance of vision systems for autonomous mobile robots; (2) To study the fine structure of insect flight trajectories in order to better understand the characteristics of flight control, orientation and navigation.

  11. Feasibility study of algae-based CO2 capture

    EPA Science Inventory

    The biomass of microalgae contains approximately 50% carbon, which is commonly obtained from the atmosphere, but can also be taken from commercial sources that produce CO2, such as coal-fired power plants. A study of operational demonstration projects is being undertaken to eval...

  12. Computer-Based Concept Mapping: Active Studying for Active Learners.

    ERIC Educational Resources Information Center

    Anderson-Inman, Lynne; Zeitz, Leigh

    1993-01-01

    Describes the use of computer-generated concept maps using a new genre of graphics programs that allows students to create, alter and expand maps as they acquire more subject matter knowledge. Four examples of increasingly complex concept maps developed by a high school student studying cellular biology are discussed and illustrated. (Contains 19…

  13. Voyages in Primary Social Studies: A Story-Based Approach.

    ERIC Educational Resources Information Center

    Clarke, Gerry; And Others

    1993-01-01

    Inspired by Brendan's fantastic sea adventures, this article describes a cooperative university-faculty project to redesign the elementary social studies curriculum in Fredericton, New Brunswick. The new plan employs literature (biography, historical novels, travel accounts, myths and legends, religious stories, poetry, and drama) to enliven study…

  14. Student attendance during college-based lectures: a pilot study.

    PubMed

    Hughes, S J

    To identify the factors that influence attendance and absenteeism among a group of second-year nursing students during the theory component of the Fitness for Practice (FFP) curriculum. In 2004, a non-randomised questionnaire was used to elicit information about the factors surrounding absenteeism from 75 adult branch nursing students within the first FFP cohort. The questionnaire consisted of 48 questions and was designed to generate a mixture of quantitative and qualitative data. Absence was recorded for the first 91 weeks of the programme. The main reasons identified for absence included: illness, family commitments, dental and medical appointments, and impending assignment submissions. Other factors that might influence college attendance included a dislike of certain subjects, with ethics, law and social policy identified as the least popular subjects. Students also admitted to an increase in absence around the time when assignments are due for submission and occasionally pretended to be ill. Further studies should be undertaken with other pre-registration nursing student cohorts to compare the results with this research. There should be: an increase in self-directed learning; a 'family-friendly' approach to the curriculum by allocating self-directed study during school holidays; a reduction in the number of theory hours to coincide with students' external commitments and to assist them with the demands of studying; and time for private study before the submission of theoretical assignments.

  15. Characterizing Adolescent Prescription Misusers: A Population-Based Study

    ERIC Educational Resources Information Center

    Schepis, Ty S.; Krishnan-Sarin, Suchitra

    2008-01-01

    A study was conducted to investigate the risk factors associated with the abuse of opiods, stimulants, tranquilizers and other sedatives among adolescents aged between 12 to 17 years and the presence of one more symptoms of a substance use disorder from prescription misuse. Results indicated that poor academic performance; enjoyment of…

  16. Communication Training Needs in Organizations: A Competency/ Proficiency Based Study.

    ERIC Educational Resources Information Center

    Harris, Thomas E.; Thomlison, T. Dean

    A study examined the relationship between perceived communication competence and its importance in business organizations and the need for additional training of college business students in communication competencies. A survey was sent to all individuals who had indicated to a university center for management education and services an active…

  17. Cryptosporidiosis in Indonesia: a hospital-based study and a community-based survey.

    PubMed

    Katsumata, T; Hosea, D; Wasito, E B; Kohno, S; Hara, K; Soeparto, P; Ranuh, I G

    1998-10-01

    Hospital-based and community-based studies were conducted to understand the prevalence and mode of transmission of Cryptosporidium parvum infection in Surabaya, Indonesia. In both studies people with and without diarrhea were examined for oocysts. A community-based survey included questionnaires to a community and stool examination of cats. Questionnaires covered demographic information, health status, and hygienic indicators. In the hospital, C. parvum oocysts were found in 26 (2.8%) of 917 patients with diarrhea and 15 (1.4%) of 1,043 control patients. The most susceptible age was less than two years old. The prevalence was higher during the rainy season. A community-based study again showed that C. parvum oocysts were frequently detected in diarrhea samples (8.2%), exclusively during rainy season. Thirteen (2.4%) of 532 cats passed C. parvum oocysts. A multiple logistic regression model indicated that contact with cats, rain, flood, and crowded living conditions are significant risk factors for Cryptosporidium infection.

  18. Propranolol Reduces Cancer Risk: A Population-Based Cohort Study.

    PubMed

    Chang, Ping-Ying; Huang, Wen-Yen; Lin, Cheng-Li; Huang, Tzu-Chuan; Wu, Yi-Ying; Chen, Jia-Hong; Kao, Chia-Hung

    2015-07-01

    β-Blockers have been reported to exhibit potential anticancer effects in cancer cell lines and animal models. However, clinical studies have yielded inconsistent results regarding cancer outcomes and cancer risk when β-blockers were used. This study investigated the association between propranolol and cancer risk.Between January 1, 2000 and December 31, 2011, a patient cohort was extracted from the Longitudinal Health Insurance Database 2000, a subset of the Taiwan National Health Insurance Research Database. A propranolol cohort (propranolol usage >6 months) and nonpropranolol cohort were matched using a propensity score. Cox proportional hazard models were used to estimate the hazard ratio (HR) and 95% confidence intervals (CIs) of cancer associated with propranolol treatment.The study sample comprised 24,238 patients. After a 12-year follow-up period, the cumulative incidence for developing cancer was low in the propranolol cohort (HR: 0.75; 95% CI: 0.67-0.85; P < 0.001). Patients with propranolol treatment exhibited significantly lower risks of cancers in head and neck (HR: 0.58; 95% CI: 0.35-0.95), esophagus (HR: 0.35; 95% CI: 0.13-0.96), stomach (HR: 0.54; 95% CI: 0.30-0.98), colon (HR: 0.68; 95% CI: 0.49-0.93), and prostate cancers (HR: 0.52; 95% CI: 0.33-0.83). The protective effect of propranolol for head and neck, stomach, colon, and prostate cancers was most substantial when exposure duration exceeded 1000 days.This study supports the proposition that propranolol can reduce the risk of head and neck, esophagus, stomach, colon, and prostate cancers. Further prospective study is necessary to confirm these findings.

  19. Content-based versus semantic-based retrieval: an LIDC case study

    NASA Astrophysics Data System (ADS)

    Jabon, Sarah A.; Raicu, Daniela S.; Furst, Jacob D.

    2009-02-01

    Content based image retrieval is an active area of medical imaging research. One use of content based image retrieval (CBIR) is presentation of known, reference images similar to an unknown case. These comparison images may reduce the radiologist's uncertainty in interpreting that case. It is, therefore, important to present radiologists with systems whose computed-similarity results correspond to human perceived-similarity. In our previous work, we developed an open-source CBIR system that inputs a computed tomography (CT) image of a lung nodule as a query and retrieves similar lung nodule images based on content-based image features. In this paper, we extend our previous work by studying the relationships between the two types of retrieval, content-based and semantic-based, with the final goal of integrating them into a system that will take advantage of both retrieval approaches. Our preliminary results on the Lung Image Database Consortium (LIDC) dataset using four types of image features, seven radiologists' rated semantic characteristics and two simple similarity measures show that a substantial number of nodules identified as similar based on image features are also identified as similar based on semantic characteristics. Furthermore, by integrating the two types of features, the similarity retrieval improves with respect to certain nodule characteristics.

  20. An instrument for the assessment of diarrhoeal severity based on a longitudinal community-based study.

    PubMed

    Lee, Gwenyth; Peñataro Yori, Pablo; Paredes Olortegui, Maribel; Caulfield, Laura E; Sack, David A; Fischer-Walker, Christa; Black, Robert E; Kosek, Margaret

    2014-06-06

    Diarrhoea is a significant contributer to morbidity and is among the leading causes of death of children living in poverty. As such, the incidence, duration and severity of diarrhoeal episodes in the household are often key variables of interest in a variety of community-based studies. However, there currently exists no means of defining diarrhoeal severity that are (A) specifically designed and adapted for community-based studies, (B) associated with poorer child outcomes and (C) agreed on by the majority of researchers. Clinical severity scores do exist and are used in healthcare settings, but these tend to focus on relatively moderate-to-severe dehydrating and dysenteric disease, require trained observation of the child and, given the variability of access and utilisation of healthcare, fail to sufficiently describe the spectrum of disease in the community setting. Longitudinal cohort study. Santa Clara de Nanay, a rural community in the Northern Peruvian Amazon. 442 infants and children 0-72 months of age. Change in weight over 1-month intervals and change in length/height over 9-month intervals. Diarrhoeal episodes with symptoms of fever, anorexia, vomiting, greater number of liquid stools per day and greater number of total stools per day were associated with poorer weight gain compared with episodes without these symptoms. An instrument to measure the severity was constructed based on the duration of these symptoms over the course of a diarrhoeal episode. In order to address limitations of existing diarrhoeal severity scores in the context of community-based studies, we propose an instrument comprised of diarrhoea-associated symptoms easily measured by community health workers and based on the association of these symptoms with poorer child growth. This instrument can be used to test the impact of interventions on the burden of diarrhoeal disease. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a

  1. An instrument for the assessment of diarrhoeal severity based on a longitudinal community-based study

    PubMed Central

    Lee, Gwenyth; Peñataro Yori, Pablo; Paredes Olortegui, Maribel; Caulfield, Laura E; Sack, David A; Fischer-Walker, Christa; Black, Robert E; Kosek, Margaret

    2014-01-01

    Objective Diarrhoea is a significant contributer to morbidity and is among the leading causes of death of children living in poverty. As such, the incidence, duration and severity of diarrhoeal episodes in the household are often key variables of interest in a variety of community-based studies. However, there currently exists no means of defining diarrhoeal severity that are (A) specifically designed and adapted for community-based studies, (B) associated with poorer child outcomes and (C) agreed on by the majority of researchers. Clinical severity scores do exist and are used in healthcare settings, but these tend to focus on relatively moderate-to-severe dehydrating and dysenteric disease, require trained observation of the child and, given the variability of access and utilisation of healthcare, fail to sufficiently describe the spectrum of disease in the community setting. Design Longitudinal cohort study. Setting Santa Clara de Nanay, a rural community in the Northern Peruvian Amazon. Participants 442 infants and children 0–72 months of age. Main outcome measures Change in weight over 1-month intervals and change in length/height over 9-month intervals. Results Diarrhoeal episodes with symptoms of fever, anorexia, vomiting, greater number of liquid stools per day and greater number of total stools per day were associated with poorer weight gain compared with episodes without these symptoms. An instrument to measure the severity was constructed based on the duration of these symptoms over the course of a diarrhoeal episode. Conclusions In order to address limitations of existing diarrhoeal severity scores in the context of community-based studies, we propose an instrument comprised of diarrhoea-associated symptoms easily measured by community health workers and based on the association of these symptoms with poorer child growth. This instrument can be used to test the impact of interventions on the burden of diarrhoeal disease. PMID:24907244

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

    PubMed

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

    2017-03-28

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

  3. Lunar base surface mission operations. Lunar Base Systems Study (LBSS) task 4.1

    NASA Technical Reports Server (NTRS)

    1987-01-01

    The purpose was to perform an analysis of the surface operations associated with a human-tended lunar base. Specifically, the study defined surface elements and developed mission manifests for a selected base scenario, determined the nature of surface operations associated with this scenario, generated a preliminary crew extravehicular and intravehicular activity (EVA/IVA) time resource schedule for conducting the missions, and proposed concepts for utilizing remotely operated equipment to perform repetitious or hazardous surface tasks. The operations analysis was performed on a 6 year period of human-tended lunar base operation prior to permanent occupancy. The baseline scenario was derived from a modified version of the civil needs database (CNDB) scenario. This scenario emphasizes achievement of a limited set of science and exploration objectives while emplacing the minimum habitability elements required for a permanent base.

  4. A Thematic Review of Studies into the Effectiveness of Context-Based Chemistry Curricula

    ERIC Educational Resources Information Center

    Ultay, Neslihan; Calik, Muammer

    2012-01-01

    Context-based chemistry education aims at making connections between real life and the scientific content of chemistry courses. The purpose of this study was to evaluate context-based chemistry studies. In looking for the context-based chemistry studies, the authors entered the keywords "context-based", "contextual learning" and "chemistry…

  5. A Thematic Review of Studies into the Effectiveness of Context-Based Chemistry Curricula

    ERIC Educational Resources Information Center

    Ultay, Neslihan; Calik, Muammer

    2012-01-01

    Context-based chemistry education aims at making connections between real life and the scientific content of chemistry courses. The purpose of this study was to evaluate context-based chemistry studies. In looking for the context-based chemistry studies, the authors entered the keywords "context-based", "contextual learning" and "chemistry…

  6. Studying Light in the Fifth Grade: A Case Study of Text-Based Science Teaching. Research Series No. 129.

    ERIC Educational Resources Information Center

    Slinger, Lucille A.; And Others

    This study documents text-based science instruction as it actually occurred in the classroom of a fifth-grade teacher teaching the unit on light found in "Exploring Science" by M.K. Blecha, P.C. Gega, and M. Green (1979, Laidlaw Brothers). The study, focusing on the nature of and reasons for the teacher's successes and failures, examined…

  7. [Study on commercial specification of atractylodes based on Delphi method].

    PubMed

    Wang, Hao; Chen, Li-Xiao; Huang, Lu-Qi; Zhang, Tian-Tian; Li, Ying; Zheng, Yu-Guang

    2016-03-01

    This research adopts "Delphi method" to evaluate atractylodes traditional traits and rank correlation. By using methods of mathematical statistics the relationship of the traditional identification indicators and atractylodes goods rank correlation was analyzed, It is found that the main characteristics affectingatractylodes commodity specifications and grades of main characters wereoil points of transaction,color of transaction,color of surface,grain of transaction,texture of transaction andspoilage. The study points out that the original "seventy-six kinds of medicinal materials commodity specification standards of atractylodes differentiate commodity specification" is not in conformity with the actual market situation, we need to formulate corresponding atractylodes medicinal products specifications and grades.This study combined with experimental results "Delphi method" and the market actual situation, proposed the new draft atractylodes commodity specifications and grades, as the new atractylodes commodity specifications and grades standards. It provides a reference and theoretical basis. Copyright© by the Chinese Pharmaceutical Association.

  8. Finite element based optimization study on hydroformed stepped tube

    NASA Astrophysics Data System (ADS)

    Harisankar, K. R.; Omar, A.; Narasimhan, K.

    2016-08-01

    Tube hydroforming process is an advanced manufacturing process in which tube is placed in between the dies and deformed with the help of hydraulic pressure. A sound tube hydroformed part depends upon die conditions, material properties and process conditions. In this work, a finite element study, along with response surface methodology (RSM) for designing the simulation, has been used to construct models with loading path, friction, anisotropic index, strain hardening exponent and tube thickness. The responses studied are the die corner radius filling and strain non-uniformity index (SNI) chosen in each step of the tube with maximum 30% thinning as stopping criteria. The factors effect and their interactions on each response were determined and analysed.

  9. Empirical study of ARFIMA model based on fractional differencing

    NASA Astrophysics Data System (ADS)

    Xiu, Jin; Jin, Yao

    2007-04-01

    In this paper, we studied the long-term memory of Hong Kong Hang Sheng index using MRS analysis, established ARFIMA model for it, and detailed the procedure of fractional differencing. Furthermore, we compared the ARFIMA model built by this means with the one that took first-order differencing as an alternative. The result showed that, if doing so, much useful information of time series would be lost. The forecast formula of ARFIMA model was corrected according to the method of fractional differencing, and was employed in the empirical study. It was illustrated that the forecast performance of ARFIMA model was not as good as we expected since the ARFIMA model was ineffective in forecasting Hang Sheng index. The certainty of this conclusion was proposed from two different aspects.

  10. FEASIBILITY STUDY II OF A MUON BASED NEUTRINO SOURCE.

    SciTech Connect

    GALLARDO,J.C.; OZAKI,S.; PALMER,R.B.; ZISMAN,M.

    2001-06-30

    The concept of using a muon storage ring to provide a well characterized beam of muon and electron neutrinos (a Neutrino Factory) has been under study for a number of years now at various laboratories throughout the world. The physics program of a Neutrino Factoryis focused on the relatively unexplored neutrino sector. In conjunction with a detector located a suitable distance from the neutrino source, the facility would make valuable contributions to the study of neutrino masses and lepton mixing. A Neutrino Factory is expected to improve the measurement accuracy of sin{sup 2}(2{theta}{sub 23}) and {Delta}m{sup 2}{sub 32} and provide measurements of sin{sup 2}(2{theta}{sub 13}) and the sign of {Delta}m{sup 2}{sub 32}. It may also be able to measure CP violation in the lepton sector.

  11. Stimulator Selection in SSVEP-Based Spatial Selective Attention Study.

    PubMed

    Xie, Songyun; Liu, Chang; Obermayer, Klaus; Zhu, Fangshi; Wang, Linan; Xie, Xinzhou; Wang, Wei

    2016-01-01

    Steady-State Visual Evoked Potentials (SSVEPs) are widely used in spatial selective attention. In this process the two kinds of visual simulators, Light Emitting Diode (LED) and Liquid Crystal Display (LCD), are commonly used to evoke SSVEP. In this paper, the differences of SSVEP caused by these two stimulators in the study of spatial selective attention were investigated. Results indicated that LED could stimulate strong SSVEP component on occipital lobe, and the frequency of evoked SSVEP had high precision and wide range as compared to LCD. Moreover a significant difference between noticed and unnoticed frequencies in spectrum was observed whereas in LCD mode this difference was limited and selectable frequencies were also limited. Our experimental finding suggested that average classification accuracies among all the test subjects in our experiments were 0.938 and 0.853 in LED and LCD mode, respectively. These results indicate that LED simulator is appropriate for evoking the SSVEP for the study of spatial selective attention.

  12. Williams Air Force Base Air Quality Monitoring Study. Appendices,

    DTIC Science & Technology

    1980-07-01

    different techniques of remote sensing were evaluated at WAFB: the SLDVS, the remote optical sensing of emissions (ROSE) system, the COSPEC system...disc collection substrates were examined by optical microscopy, and some were further examined by scanning electron microscopy. Selected nucleopore...wavelengths visible to the human eye. REMOTE OPTICAL SENSING OF EMISSIONS STUDY Long-path infrared spectroscopic measurements of CO concentrations were made

  13. Evidenced-based review of clinical studies on periodontics.

    PubMed

    2009-08-01

    Periodontal diseases have several implications for the practice of endodontics. First, advanced periodontitis often has direct implications for the long-term prognosis of the case and requires careful evaluation and coordinated treatment of both the periodontic and endodontic diseases. Second, the potential for functional interactions between odontogenic pathoses and marginal periodontitis requires careful collection of clinical observations and monitoring the outcome of various treatments. In this section, we provide an analysis of recent clinical studies in this area.

  14. Integrated genome-based studies of Shewanella ecophysiology

    SciTech Connect

    Segre Daniel; Beg Qasim

    2012-02-14

    This project was a component of the Shewanella Federation and, as such, contributed to the overall goal of applying the genomic tools to better understand eco-physiology and speciation of respiratory-versatile members of Shewanella genus. Our role at Boston University was to perform bioreactor and high throughput gene expression microarrays, and combine dynamic flux balance modeling with experimentally obtained transcriptional and gene expression datasets from different growth conditions. In the first part of project, we designed the S. oneidensis microarray probes for Affymetrix Inc. (based in California), then we identified the pathways of carbon utilization in the metal-reducing marine bacterium Shewanella oneidensis MR-1, using our newly designed high-density oligonucleotide Affymetrix microarray on Shewanella cells grown with various carbon sources. Next, using a combination of experimental and computational approaches, we built algorithm and methods to integrate the transcriptional and metabolic regulatory networks of S. oneidensis. Specifically, we combined mRNA microarray and metabolite measurements with statistical inference and dynamic flux balance analysis (dFBA) to study the transcriptional response of S. oneidensis MR-1 as it passes through exponential, stationary, and transition phases. By measuring time-dependent mRNA expression levels during batch growth of S. oneidensis MR-1 under two radically different nutrient compositions (minimal lactate and nutritionally rich LB medium), we obtain detailed snapshots of the regulatory strategies used by this bacterium to cope with gradually changing nutrient availability. In addition to traditional clustering, which provides a first indication of major regulatory trends and transcription factors activities, we developed and implemented a new computational approach for Dynamic Detection of Transcriptional Triggers (D2T2). This new method allows us to infer a putative topology of transcriptional dependencies

  15. Epidemiology of psoriasis in malaysia: a hospital based study.

    PubMed

    Sinniah, B; Saraswathy Devi, S; Prashant, B S

    2010-06-01

    Psoriasis is a complex chronic inflammatory skin disease with a worldwide distribution. To determine the prevalence of psoriasis according to age, gender and ethnicity among outpatients attending the dermatology clinic in Hospital Tengku Ampuan Rahimah, Klang Malaysia. All outpatients attending the specialist clinic of the dermatology department in Hospital Tengku Ampuan Rahimah, Klang, Malaysia from January 2003 to December 2005. This is a retrospective descriptive study of all outpatients who attended the specialist clinic from January 2003 to December 2005 and diagnosed for psoriasis. The study population consisted of patients of all ages, both gender and different ethnic groups (Malay, Chinese, Indians and foreign workers) living in the Klang Valley and the surrounding areas. A total of 5607 patients were examined during a period of three years and 9.5% were found to be suffering with psoriasis. It was more common in males (11.6%) than in females (7.2%). Patients within the 40-60 year age group had the highest (17.2%) rate and were lower in the younger age group including those aged over 60 years (8.1%). With regards to ethnicity, it was more common in Indians followed by Malays, Chinese and migrant foreign workers respectively. The study indicates that psoriasis is common in Malaysia and its distribution varies with age, ethnicity and gender.

  16. Feasibility study of algae-based Carbon Dioxide capture ...

    EPA Pesticide Factsheets

    SUMMARY: The biomass of microalgae contains approximately 50% carbon, which is commonly obtained from the atmosphere, but can also be taken from commercial sources that produce CO2, such as coal-fired power plants. A study of operational demonstration projects is being undertaken to evaluate the benefits of using algae to reduce CO2 emissions from industrial and small-scale utility power boilers. The operations are being studied for the use of CO2 from flue gas for algae growth along with the production of biofuels and other useful products to prepare a comprehensive characterization of the economic feasibility of using algae to capture CO2. Information is being generated for analyses of the potential for these technologies to advance in the market and assist in meeting environmental goals, as well as to examine their associated environmental implications. Three electric power generation plants (coal and fuel oil fired) equipped to send flue-gas emissions to algae culture at demonstration facilities are being studied. Data and process information are being collected and developed to facilitate feasibility and modeling evaluations of the CO2 to algae technology. An understanding of process requirements to apply this technology to existing industries would go far in advancing carbon capture opportunities. Documenting the successful use of this technology could help bring “low-tech”, low-cost, CO2 to algae, carbon capture to multiple size industries and

  17. Electroresistance and field effect studies on manganite based heterostructure

    SciTech Connect

    Solanki, P. S.; Khachar, Uma; Vagadia, Megha; Ravalia, Ashish; Katba, Savan; Kuberkar, D. G.

    2015-04-14

    Electronic properties of manganites are significantly important for various spintronic applications such as microelectronics, magnetic data storage, communication technologies, and memory devices. Influence of applied electric field on the room temperature charge transport in ZnO/La{sub 0.7}Sr{sub 0.3}MnO{sub 3}/SrNb{sub 0.002}Ti{sub 0.998}O{sub 3} (SNTO) heterostructure has been investigated using field effect studies. Large negative and positive electroresistance has been observed in heterostructure under various possible circuit geometries. Field effect studies have been carried out using three different circuit geometries, namely: (i) ZnO as a control electrode (E{sub LZ}), (ii) SNTO as a control electrode (E{sub LS}), and (iii) shorted ZnO and SNTO as control electrodes (E{sub LZS}). For this, channel electric field (E{sub CH}) dependent variation in channel resistance (R{sub C}) (of manganite channel) and I-V (across manganite channel) under various control fields (E{sub C}) have been studied. Variation in barrier height (Φ{sub B}) with control field (E{sub C}) for different geometries has been discussed.

  18. Detection of electronically equivalent tautomers of adenine base: DFT study

    SciTech Connect

    Siddiqui, Shamoon Ahmad; Bouarissa, Nadir; Rasheed, Tabish; Al-Assiri, M.S.; Al-Hajry, A.

    2014-03-01

    Graphical abstract: - Highlights: • DFT calculations have been performed on adenine and its rare tautomer Cu{sup 2+} complexes. • Interaction of A-Cu{sup 2+} and rA-Cu{sup 2+} complexes with AlN modified fullerene (C{sub 60}) have been studied briefly. • It is found that AlN modified C{sub 60} could be used as a nanoscale sensor to detect these two A-Cu{sup 2+} and rA-Cu{sup 2+} complexes. - Abstract: In the present study, quantum chemical calculations were carried out to investigate the electronic structures and stabilities of adenine and its rare tautomer along with their Cu{sup 2+} complexes. Density Functional Theory (B3LYP method) was used in all calculations. The two Cu{sup 2+} complexes of adenine have almost similar energies and electronic structures; hence, their chemical differentiation is very difficult. For this purpose, interactions of these complexes with AlN modified fullerene (C{sub 60}) have been studied. Theoretical investigations reveal that AlN-doped C{sub 60} may serve as a potentially viable nanoscale sensor for detection of the two Cu{sup 2+} complexes of adenine.

  19. Oviposition behaviour of Phlebotomus argentipes - A laboratory-based study

    PubMed Central

    Kumar, Vijay; Rama, Aarti; Kesari, Shreekant; Bhunia, Gouri Sankar; Dinesh, Diwakar Singh; Das, Pradeep

    2013-01-01

    The breeding habitat of sandflies is a little studied and poorly understood phenomenon. More importantly, oviposition behaviour is a largely neglected aspect of sandfly biology and this knowledge gap further undermines our understanding of the biology of sandflies. Pheromones released by the eggs play an important role in identifying good sites for oviposition by female insects. Several recent studies have examined the oviposition pheromone. The present study provides a preliminary report on the oviposition behaviour of Phlebotomus argentipes, the only vector of kala-azar (or visceral leishmaniasis) on the Indian sub-continent. Sandflies prefer to oviposit their eggs on surfaces that contain organic substances, especially substances with an odour of decaying animal products and the remains of conspecific eggs. The results presented here suggest that the odour released by the organic substances of old sandfly colony remains that contain dead flies, old unhatched eggs, larval food containing vertebrate faeces, frass and other organic matter serves as an attractant for the ovipositing females of P. argentipes and hence greatly increases the number of oviposited eggs compared to eggs deposited in controlled oviposition pots. This result will be helpful in maintaining an efficient colony of P. argentipes and may be a promising tool for monitoring and controlling the target insect as part of a synergistic approach. PMID:24141963

  20. Electroresistance and field effect studies on manganite based heterostructure

    NASA Astrophysics Data System (ADS)

    Solanki, P. S.; Khachar, Uma; Vagadia, Megha; Ravalia, Ashish; Katba, Savan; Kuberkar, D. G.

    2015-04-01

    Electronic properties of manganites are significantly important for various spintronic applications such as microelectronics, magnetic data storage, communication technologies, and memory devices. Influence of applied electric field on the room temperature charge transport in ZnO/La0.7Sr0.3MnO3/SrNb0.002Ti0.998O3 (SNTO) heterostructure has been investigated using field effect studies. Large negative and positive electroresistance has been observed in heterostructure under various possible circuit geometries. Field effect studies have been carried out using three different circuit geometries, namely: (i) ZnO as a control electrode (ELZ), (ii) SNTO as a control electrode (ELS), and (iii) shorted ZnO and SNTO as control electrodes (ELZS). For this, channel electric field (ECH) dependent variation in channel resistance (RC) (of manganite channel) and I-V (across manganite channel) under various control fields (EC) have been studied. Variation in barrier height (ΦB) with control field (EC) for different geometries has been discussed.

  1. Web-based tracking methods in longitudinal studies.

    PubMed

    Williams, Izaak L; O'Donnell, Clifford R

    2014-08-01

    The use of online resources to reduce the attrition of program participants in longitudinal studies is examined. Higher-risk individuals, those involved in illegal activities, and females with last name changes are typically more difficult to locate. The effectiveness of using online resources for these participants is addressed. These resources include social networking sites, people-finder search engines, telephone and address directories, judicial records, and death records. The strengths and limitations of these resources are presented and discussed. Longitudinal studies using these resources are examined to evaluate their successful follow-up rates. The results of these studies indicate that participant characteristics are more important to successful follow-up than the length of time since participation or sample size. The use of multiple online sites increased follow-up rates, especially for those who are typically difficult to locate. The variables and websites to consider are discussed, and six lessons learned are offered. The prospective use of online participant involvement is especially important for successful longitudinal evaluation and program planning.

  2. Drug-DNA Interaction Studies of Acridone-Based Derivatives.

    PubMed

    Thimmaiah, Kuntebomanahalli; Ugarkar, Apoorva G; Martis, Elvis F; Shaikh, Mushtaque S; Coutinho, Evans C; Yergeri, Mayur C

    2015-01-01

    N10-alkylated 2-bromoacridones are a novel series of potent antitumor compounds. DNA binding studies of these compounds were carried out using spectrophotometric titrations, Circular dichroism (CD) measurements using Calf Thymus DNA (CT DNA). The binding constants were identified at a range of K=0.3 to 3.9×10(5) M(-1) and the percentage of hypochromism from the spectral titrations at 28-54%. This study has identified a compound 9 with the good binding affinity of K=0.39768×10(5) M(-1) with CT DNA. Molecular dynamics (MD) simulations have investigated the changes in structural and dynamic features of native DNA on binding to the active compound 9. All the synthesized compounds have increased the uptake of Vinblastine in MDR KBChR-8-5 cells to an extent of 1.25- to1.9-fold than standard modulator Verapamil of similar concentration. These findings allowed us to draw preliminary conclusions about the structural features of 2-bromoacridones and further chemical enhancement will improve the binding affinity of the acridone derivatives to CT-DNA for better drug-DNA interaction. The molecular modeling studies have shown mechanism of action and the binding modes of the acridones to DNA.

  3. Australian snowboard injury data base study. A four-year prospective study.

    PubMed

    Bladin, C; Giddings, P; Robinson, M

    1993-01-01

    Information on the rate and spectrum of snowboarding injuries is limited. This 4-year prospective study at 3 major Australian ski resorts assesses incidence and patterns of snowboarding injuries, particularly in relation to skill level and footwear. Ski injury data were collected for the same period. In a predominantly male study population (men:women, 3:1), 276 snowboarding injuries were reported; 58% occurred in novices. Fifty-seven percent of injuries were in the lower limbs, 30% in the upper limbs. The most common injuries were sprains (53%), fractures (24%), and contusions (12%). Comparing skiers' versus snowboarders' injuries, snowboarders had 2.4 times as many fractures, particularly to the upper limbs (21% versus 35% of upper limb injuries), fewer knee injuries (23% versus 44% of lower limb injuries), but more ankle injuries (23% versus 6% of lower limb injuries). Ankle injuries were more common with soft-shell boots, worn most by intermediate and advanced riders. Knee injuries and distal tibial fractures were more common with hard-shell boots, worn most by novices. Overall, novices had more upper limb fractures and knee injuries; intermediate and advanced riders had more ankle injuries. Falls were the principal mode of injury. To prevent injury, beginners should use "hybrid" or soft-shell boots and take lessons.

  4. Fermi surface studies of Co-based Heusler alloys: Ab-initio study

    NASA Astrophysics Data System (ADS)

    Ram, Swetarekha; Kanchana, V.

    2013-02-01

    The electronic, Fermi surface (FS) and magnetic properties of ferromagnetic Heusler alloys Co2XY (X = Cr, Mn, Fe; Y=Al, Ga) have been investigated by means of first principles calculation. Out of these compounds, Co2CrAl is found to be perfectly half-metallic (HM) at ambient. Under pressure HM to nearly HM (NHM) transition is observed around 75 GPa for Co2CrAl and NHM to HM transition is observed around 40 GPa and 18 GPa for Co2CrGa and Co2MnAl, respectively, while no transition is observed for other compounds under study and is also analyzed from the FS studies. The states at the Fermi level in the majority spin are strongly hybridized Co-d and X-d like states. The majority band FS topology change is observed under pressure for the compounds where we observe a transition, while the minority band FS remain unaltered under pressure for all compounds except in Co2FeGa, where we observed an electron sheet at X point instead of hole pocket at Γ point.

  5. HPLC & NMR-based forced degradation studies of ifosfamide: The potential of NMR in stability studies.

    PubMed

    Salman, D; Peron, J-M R; Goronga, T; Barton, S; Swinden, J; Nabhani-Gebara, S

    2016-03-01

    The aim of this study is to conduct a forced degradation study on ifosfamide under several stress conditions to investigate the robustness of the developed HPLC method. It also aims to provide further insight into the stability of ifosfamide and its degradation profile using both HPLC and NMR. Ifosfamide solutions (20mg/mL; n=15, 20mL) were stressed in triplicate by heating (70°C), under acidic (pH 1 & 4) and alkaline (pH 10 & 12) conditions. Samples were analysed periodically using HPLC and FT-NMR. Ifosfamide was most stable under weakly acidic conditions (pH 4). NMR results suggested that the mechanism of ifosfamide degradation involves the cleavage of the PN bond. For all stress conditions, HPLC was not able to detect ifosfamide degradation products that were detected by NMR. These results suggest that the developed HPLC method for ifosfamide did not detect the degradation products shown by NMR. It is possible that degradation products co-elute with ifosfamide, do not elute altogether or are not amenable to the detection method employed. Therefore, investigation of ifosfamide stability requires additional techniques that do not suffer from the aforementioned shortcomings. Copyright © 2015 Académie Nationale de Pharmacie. Published by Elsevier Masson SAS. All rights reserved.

  6. Ground-based interferometric studies of auroral roar

    NASA Astrophysics Data System (ADS)

    Hughes, John Mark

    2000-09-01

    Auroral roar is a naturally-occurring radio emission generated in the Earth's auroral ionosphere at frequencies near 3 MHz and 4.5 MHz and believed to occur at harmonics of the ionsopheric electron cyclotron frequency (2 fce and 3fce). Although the first observations of auroral roar were reported more than 20 years ago, a satisfactory mechanism for generating the emissions has not been found. A principle reason for this is that previous studies have been made using non- directional antennas which give no information about the location of the auroral roar source regions. This thesis describes the development of the medium- frequency interferometer (MFI), the first direction- sensitive instrument capable of detecting auroral roar events, and discusses a series of experiments designed to study the generation mechanism and propagation characteristics of 2fce auroral roar. Data from the MFI reveal that auroral roar is generated in both the bottom and top sides of the ionsopheric F-region and that it can propagate to the ground from both these locations. The data also reveal that individual auroral roar events often propagate to the MFI from more than one direction, implying the existence of more than one source region. Statistical and case study analyses suggest that auroral roar is usually generated near the poleward edge of the auroral oval. Electron density measurements from the Sondrestrom incoherent scatter radar have been used to test one candidate generation mechanism which suggests that 2fce auroral roar is generated as an electrostatic upper hybrid wave at places where the upper hybrid frequency matches twice the electron cyclotron frequency. In each of the five available cases, this matching condition is met in the auroral roar source region. Finally, observations and numerical simulations of a recently observed phenomenon known as flickering auroral roar are presented. Numerical simulations suggest that flickering auroral roar may be caused by auroral

  7. Fluorescence Based Study for Melamine Detection Using Gold Colloidal Solutions.

    PubMed

    Paul, Ida Evangeline; Rajeshwari, A; Satija, Jitendra; Raichur, Ashok M; Chandrasekaran, N; Mukherjee, Amitava

    2016-11-01

    A comparative study on detection of melamine with different sized citrate capped AuNPs namely 15 nm (AuNPs-I), 30 nm (AuNPs-II), and 40 nm (AuNPs-III) was carried out by fluorescence spectroscopy. The AuNPs emitted strong fluorescence at 421 nm with different intensity at 116.122, 220.511 and 253.665 for AuNPs-I, AuNPs-II and AuNPs-III respectively on excitation with 308 nm. On interaction with melamine, the AuNPs aggregated resulting in the enhancement of the fluorescent intensity of AuNPs. The sensitivity of melamine detection was studied for three different sizes of AuNPs by drawing a calibration curve between the concentration of melamine and fluorescence intensity. A good sensitivity was observed for AuNPs-II having the detection limit as low as 0.66 nM (3σ) which was lower in comparison to the detection limit of AuNPs-I (2.78 nM) and AuNPs-III (7.74 nM). The cost of synthesis was low as the usage of HAuCl4 in the synthesis of AuNPs-II was lower compared to the other sizes of AuNPs resulting in low cost of chemicals. The AuNPs-II was further chosen for carrying out selectivity study and for detecting the concentration of melamine. The recovery percentage of melamine in raw milk, liquid milk and milk powder after pre-treatment was found to be 100 %, 97 % to 100 % and 94 % to 99 % respectively.

  8. Dermatological problems in geriatric patients: a hospital based study.

    PubMed

    Thapa, D P; Jha, A K; Kharel, C; Shrestha, S

    2012-09-01

    Geriatric health care has become a major issue worldwide. There are no data regarding geriatric dermatologic diseases are available from Nepal. Patients of 60 years and above were enrolled in the Nepali fiscal year 2067(April 2010-April 2011). The data included age, sex, place, and diagnosis. The aim of the study is to determine the characteristic pattern and frequency of dermatoses in dermatologic patients aged 60 years and above. There were total of 6442 patients who visited out patients department. Out of which frequency of geriatric patients were 330, which constitute about 5.1%. The male to female ratio was 50% each. The most common cutaneous dermatoses was eczema 35.8%, fungal infection 13.6%, viral infection 7%, followed by pruritus 7.3%, scabies and photodermatitis 4.5% each, Inflammatory papulosquamous disorder 3.3%, Bacterial infection and Icthyosis 2.1% each, vesiculobullous 1.8%, tumors and pigmentary disorder 0.6% and Miscellaneous group (keratoderma, callus, urticaria, diabetic ulcer, burgers disease, burning feet syndrome, Rosacea, Drug rash-amoxicillin, senile acne, prurigo nodularis, hansens disease, pellagra, Actinic cheilitis) 15.8%. Few patients had more than one dermatoses which constitute < 1% .Photodermatitis was found to be statistically significant. The most common dermatoses were Eczema in females followed by Photodermatitis and comparatively in males viral and fungal infections were common. This study depicts various characteristic patterns of dermatoses seen in elderly. Eczema and infections was found to be most common diseases seen in elderly. Further epidemiologic studies including treatment, follow-up of elderly patients has to be carried out to know the burden of the disease and decrease morbidity and psychological concern associated with diseases.

  9. Study of the dual water model based on log data

    SciTech Connect

    Coates, G.R.; Boutemy, Y.; Clavier, C.

    1981-01-01

    In 1976 a proposal was made to modify the Waxman Smits model for analysis of shaly sands. Central to the proposal was the concept that clayey formations contain two distinct waters; clay or bound water being the water adhered to clay particles and free water being the familiar connate or formation water. In this paper log evidence is presented to support the validity of the Dual Wate hypothesis. Presented first are the dielectric studies which originally suggested the possible existence of two waters. Then, evidence is offered from various field logs which respond to the amount and nature of formation waters. 4 refs.

  10. A Lithographic Study of Photoresists Containing a Base Soluble Dye

    NASA Astrophysics Data System (ADS)

    Cagan, Myron R.; Blanco, Michael A.; Wise, V.; Trefonas, Peter; Daniels, Brian K.; McCants, Clayton L.

    1989-08-01

    This paper examines the performance of a specific family of dyed resists. The effect of dye con-centration on the line profiles of a homologous series of positive photoresists is studied. Usable images are obtained with dye concentrations of 0%, 0.4%, and 0.6% (percentage of the formulation). Both standard softbake or a softbake plus post-exposure bake (PEB) processes are used. Resist linewidths and cross-sections are measured on substrates that are representative of those encountered on integrated circuits. Optical exposure and develop simulation parameters (two developers) for this family of resists are also extracted.

  11. Agent-based modeling: case study in cleavage furrow models

    PubMed Central

    Mogilner, Alex; Manhart, Angelika

    2016-01-01

    The number of studies in cell biology in which quantitative models accompany experiments has been growing steadily. Roughly, mathematical and computational techniques of these models can be classified as “differential equation based” (DE) or “agent based” (AB). Recently AB models have started to outnumber DE models, but understanding of AB philosophy and methodology is much less widespread than familiarity with DE techniques. Here we use the history of modeling a fundamental biological problem—positioning of the cleavage furrow in dividing cells—to explain how and why DE and AB models are used. We discuss differences, advantages, and shortcomings of these two approaches. PMID:27811328

  12. Biocompatibility study on Ni-free Ti-based and Zr-based bulk metallic glasses.

    PubMed

    Li, T H; Wong, P C; Chang, S F; Tsai, P H; Jang, J S C; Huang, J C

    2017-06-01

    Safety and reliability are crucial issues for medical instruments and implants. In the past few decays, bulk metallic glasses (BMGs) have drawn attentions due to their superior mechanical properties, good corrosion resistance, antibacterial and good biocompatibility. However, most Zr-based and Ti-based BMGs contain Ni as an important element which is prone to human allergy problem. In this study, the Ni-free Ti-based and Zr-based BMGs, Ti40Zr10Cu36Pd14, and Zr48Cu36Al8Ag8, were selected for systematical evaluation of their biocompatibility. Several biocompatibility tests, co-cultural with L929 murine fibroblast cell line, were carried out on these two BMGs, as well as the comparison samples of Ti6Al4V and pure Cu. The results in terms of cellular adhesion, cytotoxicity, and metallic ion release affection reveal that the Ti40Zr10Cu36Pd14 BMG and Ti6Al4V exhibit the optimum biocompatibility; cells still being attached on the petri dish with good adhesion and exhibiting the spindle shape after direct contact test. Furthermore, the Ti40Zr10Cu36Pd14 BMG showed very low Cu ion release level, in agreement with the MTT results. Based on the current findings, it is believed that Ni-free Ti-based BMG can act as an ideal candidate for medical implant. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Community based study of sleep bruxism during early childhood

    PubMed Central

    Insana, Salvatore P.; Gozal, David; McNeil, Daniel W.; Montgomery-Downs, Hawley E.

    2012-01-01

    Objectives The aims for this study were to determine the prevalence of sleep-bruxism among young children, explore child behavior problems that may be associated with sleep-bruxism, and identify relations among sleep-bruxism, health problems, and neurocognitive performance. Methods The current study was a retrospective analysis of parent report surveys, and behavioral and neurocognitive assessments. Parents of 1953 preschool and 2888 first grade children indicated their child’s frequency of bruxism during sleep. A subsample of preschool children (n = 249) had additional behavioral, as well as neurocognitive assessments. Among the subsample, parents also reported on their child’s health, and completed the Child Behavioral Checklist; children were administered the Differential Ability Scales, and Pre-Reading Abilities subtests of the Developmental Neuropsychological Assessment. Results 36.8% of preschoolers and 49.6% of first graders were reported to brux ≥ 1 time per week. Among the preschool subsample, bruxing was independently associated with increased internalizing behaviors (β = .17). Bruxism was also associated with increased health problems (β = .19), and increased health problems were associated with decreased neurocognitive performance (β = .22). Conclusions The prevalence of sleep-bruxism was high. A dynamic and potentially clinically relevant relation exists among sleep-bruxism, internalizing behaviors, health, and neurocognition. Pediatric sleep-bruxism may serve as a sentinel marker for possible adverse health conditions, and signal a need for early intervention. These results support the need for an interdisciplinary approach to pediatric sleep medicine, dentistry, and psychology. PMID:23219144

  14. Stimulator Selection in SSVEP-Based Spatial Selective Attention Study

    PubMed Central

    Liu, Chang; Zhu, Fangshi; Wang, Linan; Xie, Xinzhou; Wang, Wei

    2016-01-01

    Steady-State Visual Evoked Potentials (SSVEPs) are widely used in spatial selective attention. In this process the two kinds of visual simulators, Light Emitting Diode (LED) and Liquid Crystal Display (LCD), are commonly used to evoke SSVEP. In this paper, the differences of SSVEP caused by these two stimulators in the study of spatial selective attention were investigated. Results indicated that LED could stimulate strong SSVEP component on occipital lobe, and the frequency of evoked SSVEP had high precision and wide range as compared to LCD. Moreover a significant difference between noticed and unnoticed frequencies in spectrum was observed whereas in LCD mode this difference was limited and selectable frequencies were also limited. Our experimental finding suggested that average classification accuracies among all the test subjects in our experiments were 0.938 and 0.853 in LED and LCD mode, respectively. These results indicate that LED simulator is appropriate for evoking the SSVEP for the study of spatial selective attention. PMID:28044073

  15. Satellite based study of stratospheric gravity waves generated by topography

    NASA Astrophysics Data System (ADS)

    Kumar, K. N.; Thokuluwa, R.; Musali, K.

    2011-12-01

    Atmospheric Gravity Waves (AGWs) are oscillations manifested in atmospheric thermodynamic parameters like wind velocities, temperature, air density, pressure etc. at all altitudes in the atmosphere. The important sources of AGWs include wind flows over topography, latent heating of the atmosphere associated with convection, strong wind shears, adjustment of unbalanced flows in the vicinity of jet streams and frontal systems etc. Of these, mountain waves generated by airflow over topography are believed to be one of the dominant sources, particularly in the extra-tropics during winter. The study of mountain waves has been considered valuable by the scientific community for reasons such as, their impact on aviation, formation of rectilinear clouds etc. Moreover, mountain waves can easily transport momentum and energy vertically up through the middle atmosphere and the effect of which is essential to understand the general middle atmospheric circulation and chemistry. In the present study, we describe a mountain wave event observed in three dimensions using Atmospheric Infrared Sounder (AIRS) satellite measured atmospheric radiance and temperatures over the western Himalayan mountain region. As a supplement to the AIRS measurements, we have also used the temperature information obtained from Microwave Limb Sounder (MLS). The mountain wave event is also well represented in the high resolution Modern Era Retrospective-analysis for Research and Applications (MERRA) reanalysis data. It is found also close agreement between the observed and theoretical vertical wavelengths for a stationary gravity wave calculated reanalysis winds. Using three dimensional (3d) wave properties of the wave, we also estimated the wave momentum flux.

  16. Female employment and fertility: a study based on Chilean data.

    PubMed

    Peek, P

    1975-01-01

    Conflicting studies bring into question the hypothesis that increased employment opportunities for women in the modern sector would reduce the population growth rate. To help clarify the situation, data from about 4000 families in central Chile, obtained from interviews in 1965, are used to test 3 hypotheses: 1) that in the traditional sector of the economy, young children do not adversely affect the mother's labor force participation; 2) that in the modern sector, child care reduces labor force participation unless there are relatives or older children to look after the young children; and 3) that young children also have a positive influence on female employment in that they increase the need for added income. This would be particularly true in the traditional sector where average household income is lower. All hypotheses were proved true by the data. Furthermore, the positive effect on the mother's employment of a larger family size proved to be true in the modern sector as well as the traditional sector. The study indicates that if a country's objective is to lower the population growth rate, a population planning program relying on higher rates of fe male employment will have to be accompanied by other socioeconomic policies intended to achieve a higher level of economic development.

  17. Estimating heritability for cause specific mortality based on twin studies.

    PubMed

    Scheike, Thomas H; Holst, Klaus K; Hjelmborg, Jacob B

    2014-04-01

    There has been considerable interest in studying the magnitude and type of inheritance of specific diseases. This is typically derived from family or twin studies, where the basic idea is to compare the correlation for different pairs that share different amount of genes. We here consider data from the Danish twin registry and discuss how to define heritability for cancer occurrence. The key point is that this should be done taking censoring as well as competing risks due to e.g.  death into account. We describe the dependence between twins on the probability scale and show that various models can be used to achieve sensible estimates of the dependence within monozygotic and dizygotic twin pairs that may vary over time. These dependence measures can subsequently be decomposed into a genetic and environmental component using random effects models. We here present several novel models that in essence describe the association in terms of the concordance probability, i.e., the probability that both twins experience the event, in the competing risks setting. We also discuss how to deal with the left truncation present in the Nordic twin registries, due to sampling only of twin pairs where both twins are alive at the initiation of the registries.

  18. Expert views on clinical supervision: a study based on interviews.

    PubMed

    Severinsson, E I; Borgenhammar, E V

    1997-05-01

    Clinical supervision is a didactic process of the purpose of human development and maturity. The aim of this study is to analyse views on clinical supervision held by a number of experts, and to reflect on the effects and value of clinical supervision in relation to public health. Data were collected by interviews and analysed in accordance with the grounded theory construction model. The results showed that clinical supervision is an integration process guiding a person from 'novice to expert' by establishing a relationship of trust between supervisor and supervisee. This study indicates that implementation of systematic clinical supervision may positively affect quality of care, and patients' recovery, create improved feeling of confidence in one's work, and prevent burnout among staff. The negative aspects, as reported, were the possibility of high 'opportunity costs', e.g. the time loss for patient care by those participating in organized systematic supervision. On the other hand, clinical supervision contributes towards more efficient use of resources and hence avoids unnecessary costs. However, neither of these aspects were further elaborated on by the experts but clearly indicate an important field for further research.

  19. [Adult asthma in Mexico City: a population-based study].

    PubMed

    García-Sancho, Cecilia; Fernández-Plata, Rosario; Martínez-Briseño, David; Franco-Marina, Francisco; Pérez-Padilla, José Rogelio

    2012-01-01

    To determine the prevalence of asthma and the association between sociodemographic characteristics, spirometry, respiratory symptoms, quality of life and sleep in adults > 40 years. This report is part of our study (Latin American Research Project Obstructive Pulmonary), held in Mexico City and the metropolitan area in 2003. We used logistic regression models adjusted for study design, where asthma was the dependent and independent variable respiratory symptoms, sociodemographic and clinical characteristics among others. The prevalence of physician-diagnosed asthma was: 3.3% in men and 6.2% in women. Decreased lung function in asthmatics was observed. In multivariate analysis, after adjusting for potential confounders, asthmatics had a higher risk of excessive daytime sleepiness more snoring [OR = 3.2 (95% CI 1.4-7.4), p= 0.008], and more frequent work absences due to respiratory problems [OR = 5.1 (95% CI 2.5-10.4), p<0.0001]. The prevalence of asthma was 5%. Asthmatics showed lower quality of life and lung function.

  20. Suicidal Decapitation by Hanging-A Population-based Study.

    PubMed

    Byard, Roger W; Gilbert, John D

    2017-09-08

    A prospective study was undertaken at Forensic Science SA over a 15-year period from July 2002 to June 2017 for all cases of adult (>18 years) suicidal hangings with decapitation. A total of 1446 cases of suicidal hangings were identified from a general population of approximately 1.5 million (1206 males-age range 18-97 years, average 42.6; and 240 females-age range 18-96 years, average 40.1). Only three cases of decapitation were found, all from long-drop hangings; these consisted of three males (ages 32-55 years; average 45 years). Spinal transections had occurred between the first and second, second and third, and third and fourth cervical vertebrae, respectively. In this study, the number of suicidal hangings with decapitation represented only 0.2% of the total number of hangings. These events are therefore extremely rare, most likely due to most suicidal hangings occurring from relatively low levels in a domestic environment. © 2017 American Academy of Forensic Sciences.

  1. Stigmatisation in onychomycosis patients: a population-based study.

    PubMed

    Szepietowski, Jacek C; Reich, Adam

    2009-07-01

    Patients with onychomycosis may experience significant psychosocial problems, similarly to other skin diseases. The objectives of this study were to analyse the level of stigmatisation among subjects with onychomycosis and the effect of anti-mycotic therapy on this feeling. This prospective study was carried out among 1684 patients (1050 women and 634 men, mean age 52.2 ± 15.5 years) with onychomycosis. All subjects were asked to fulfil the stigmatisation questionnaire at the baseline visit and after the completion of the anti-mycotic therapy. Stigmatisation level was assessed with reference to gender, age, education, type and duration of onychomycosis and the number of involved nails. Patients with onychomycosis reported markedly increased feeling of stigmatisation. Fingernail involvement was the major variable negatively influencing the stigmatisation level. Female patients and younger ones appeared to be more stigmatised. No significant relationships were found between stigmatisation level and education, number of involved fingernails or toenails, as well as the duration of onychomycosis. The anti-mycotic therapy resulted in significant reduction of all analysed aspects of stigmatisation to about 40% of the baseline level. Onychomycosis should be considered as an important problem for patients, significantly reducing their physical, mental and social well-being, also leading to marked stigmatisation of patients. © 2008 The Authors. Journal compilation © 2008 Blackwell Publishing Ltd.

  2. Millisecond Photoinduced Absorption Studies of Pyridine-Based Copolymer Films

    NASA Astrophysics Data System (ADS)

    Coplin, K. A.; Clark, D. T.; Jessen, S. W.; Epstein, A. J.; Fu, D.-K.; Swager, T. M.

    1997-03-01

    We present a study of the photoexcited states in copolymers of poly(p-pyridyl vinylene) and poly(p-phenylene vinylene) (PPyVPR_iV) with sidegroups R_1=C_12H_25 or R_2=COOC_12H_25 attached at the 2 and 5 positions of the phenyl ring. Previous studies discussed the millisecond photoinduced absorption (ms PA) characteristics of PPyVPR_iV powders(S.W. Jessen et al.), Synth. Met., in press.. In particular, triplet-triplet (T-T) transitions were observed at 1.6 eV for both materials. Additional polaron signatures were also observed in both the electronic ( ~ 0.85 eV) and infrared (1100 - 1600 cm-1) regions of the photoinduced spectrum. We compare these powder results with ms PA features for film morphologies of both the copolymers. We observe a weaker ( ~ 10X) T-T^* transition for copolymer films cast from xylene solution indicating a reduction in triplet exciton production as compared to powder samples. These results are contrasted with the behavior we reported(S.W. Jessen et al.), to be published. earlier for film and powder samples of the parent polymer poly(p-pyridyl vinylene).

  3. Virtual-reality-based system for controlled study of cataplexy

    NASA Astrophysics Data System (ADS)

    Augustine, Kurt E.; Cameron, Bruce M.; Camp, Jon J.; Krahn, Lois E.; Robb, Richard A.

    2002-05-01

    Cataplexy is a sudden loss of voluntary muscle control experienced by narcolepsy patients. It is usually triggered by strong, spontaneous emotions and is more common in times of stress. The Sleep Disorders Unit and the Biomedical Imaging Resource at Mayo Clinic are developing interactive display technology for reliably inducing cataplexy during clinical monitoring. The project is referred to as the Cataplexy/Narcolepsy Activation Program, or CatNAP. We have developed an automobile driving simulation that introduces humorous, surprising, and stress-inducing events and objects as the patient attempts to navigate a vehicle through a virtual town. The patient wears a head-mounted display and controls the vehicle via a driving simulator steering wheel and pedal cluster. As the patient attempts to drive through the town, various objects, sounds or conditions occur that distract, startle, frustrate or amuse. These responses may trigger a cataplectic episode, which can then be clinically evaluated. We believe CatNAP is a novel and innovative example of the effective application of virtual reality technology to study an important clinical problem that has resisted previous approaches. An evaluation phase with volunteer patients previously diagnosed with cataplexy has been completed. The prototype system is being prepared for a full clinical study.

  4. Nuclear-based methods for the study of selenium

    SciTech Connect

    Spyrou, N.M.; Akanle, O.A.; Dhani, A. )

    1988-01-01

    The essentiality of selenium to the human being and in particular its deficiency state, associated with prolonged inadequate dietary intake, have received considerable attention. In addition, the possible relationship between selenium and cancer and the claim that selenium may possess cancer-prevention properties have focused research effort. It has been observed in a number of studies on laboratory animals that selenium supplementation protects the animals against carcinogen-induced neoplastic growth in various organ sites, reduces the incidence of spontaneous mammary tumors, and suppresses the growth of transplanted tumor cells. In these research programs on the relationship between trace element levels and senile dementia and depression and the elemental changes in blood associated with selenium supplementation in a normal group of volunteers, it became obvious that in addition to establishing normal levels of elements in the population of interest, there was a more fundamental requirement for methods to be developed that would allow the study of the distribution of selenium in the body and its binding sites. The authors propose emission tomography and perturbed angular correlation as techniques worth exploring.

  5. Corneal thickness in a population-based, cross-sectional study: the Tehran Eye Study.

    PubMed

    Hashemi, Hassan; Yazdani, Kamran; Mehravaran, Shiva; KhabazKhoob, Mehdi; Mohammad, Kazem; Parsafar, Hiva; Fotouhi, Akbar

    2009-05-01

    To determine the distribution of corneal thickness at 6 different points in an Iranian population and find any possible relationship between the thickness values and some independent variables. As part of the "Tehran Eye Study," 410 people (800 eyes) aged 14 years and older, residing in the first 4 municipality areas of Tehran, were selected through a stratified random cluster sampling method. The participants were examined with Orbscan II to measure the corneal thickness at the central, thinnest, and 4 peripheral points of the cornea. In addition, the relationships between central corneal thickness (CCT) values and variables of age, sex, refractive error, pupil diameter, corneal diameter, anterior chamber depth (ACD), and body mass index were assessed. The design effect was also considered, and all estimates were standardized for age and sex. The reported results pertain to the right eyes only. The mean thickness (+/-SD) at the central and thinnest points was 555.6 +/- 39.9 and 550.7 +/- 40.6 microm, respectively. The minimum corneal thickness was below 500 microm in 9.6% of the participants. The superior area showed the largest thickness, and the thinnest point was most commonly in the inferotemporal quadrant. The mean "distance" and "thickness difference" between the central and thinnest points were 0.52 +/- 0.31 mm and 4.85 +/- 6.2 microm, respectively, and they showed a significant direct relationship (r = 0.708 and P < 0.001). Neither sex had a significant relationship with thickness values at different areas. Participants younger than 20 years, compared with those older than 20, had significantly thicker corneas (P = 0.001 for the central and thinnest points, P < 0.001 for peripheral areas). In the multiple regression model, age and ACD showed significant inverse correlations with CCT. The mean CCT in the present study was 555.6 microm, which is relatively higher in comparison with that in other ethnic groups. In the multiple regression model, age and ACD

  6. Lens power in Iranian schoolchildren: a population-based study.

    PubMed

    Hashemi, Hassan; Pakzad, Reza; Iribarren, Rafael; Khabazkhoob, Mehdi; Emamian, Mohammad Hassan; Fotouhi, Akbar

    2017-08-31

    To evaluate lens power (LP) in schoolchildren aged 6-12 years. This cross-sectional study was conducted in Shahroud, northeast Iran. The students were selected through random cluster sampling and underwent the measurements of biometry, uncorrected and corrected visual acuity, non-cycloplegic and cycloplegic refraction. The LP was calculated using the Bennett formula. Of 6624 invited children, 5620 (84.8%) participated in the study and data of 4870 children were finally analysed. The mean age of the participants was 9.7 years and 2277 participants (46.02%) were girls. The mean LPs were 22.86 dioptres (D) in total study population, 23.91 D in 6 and 22.10 D in 12-year-old children. The mean LP was higher in girls than boys (23.48 D vs 22.34 D), in rural children than urban children (23.17 D vs 22.83 D) and in children with hyperopia (23.25 D) than children with myopia or emmetropia (22.64 D and 22.86 D, respectively). In the multiple linear regression model, lens thickness (β=1.59, p<0.001), anterior chamber depth (β=2.21, p<0.001) and female sex (β=0.016, p=0.015) were associated with an increase in the LP, while axial length (AL) (β=-4.41, p<0.001), corneal power (CP) (β=-1.47, p<0.001), spherical equivalent (SE) (β=-1.50, p<0.001) and age (β=-0.005, p=0.001) were associated with a decrease in the LP. AL and sex had the highest and lowest impact on LP, respectively. LP decreased with age between 6 and 12 years and was associated with a shorter AL, deeper ACD, higher SE, thicker lens and lower CP. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  7. Space-Based Solar Power Conversion and Delivery Systems Study. Volume 3: Microwave Power Transmission Studies

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The Microwave Fower Beam Ionosphere effects and critical interfaces between th Microwave Power Transmission System (MPTS) and the Satellite were studied as part of the NASA/MSFC continuing research on the feasibility of power transmission from geosynchronous orbit. Theoretical predications of ionospheric modifications produced by the direct interaction of the MPTS on the earth's upper atmosphere are used to determine their impact on the performance of the Microwave Power Beam and Pilot Beam System as well as on other RF systems effected by the ionosphere. A technology program to quantitatively define these interactions is developed. Critical interface areas between the MPTS and the satellite which could have a major impact on cost and performance of the power system are idenfified and analyzed. The areas selected include: use of either a 20 kV versus 40 kV Amplitron, thermal blockage effects of Amplitron heat radiation by the satellite structure, effect of dielectric carry-through structure on power beam, and effect of material sublimation on performance of the Amplitron in Geosynchronous Orbit.

  8. Study Design and Results of a Population-Based Study on Perceived Stress Following Hurricane Sandy.

    PubMed

    Schwartz, Rebecca; Liu, Bian; Sison, Cristina; Kerath, Samantha M; Breil, Trista; Murphy, Lisa; Taioli, Emanuela

    2016-06-01

    Hurricane Sandy was one of the deadliest storms in US history, with at least 162 deaths and numerous injuries. This research aimed to quantify the impact of Hurricane Sandy on the New York metropolitan area. The project included 601 volunteers aged at least 18 years who were recruited in Nassau, Suffolk, Queens, and Richmond counties and Staten Island between 2013 and 2014 through close partnerships with coalition community leaders. Participants completed a self-administered questionnaire on demographics and behavioral factors and a 35-point check off list on hurricane exposure. Perceived stress was assessed by using the 10-item Perceived Stress Scale (PSS). Participants had a mean stress score of 15.6 (SD=7.3; vs general population mean of 13.0), with 30.14% of the sample categorized as "high stress" (mean≥20). In the multivariable regression analysis, age was significantly negatively associated with PSS score. A reported history of mental health issues, Hispanic ethnicity, and overall exposure to Hurricane Sandy were statistically significantly associated with PSS score in a positive direction. Perceived stress was high in areas affected by Hurricane Sandy and was significantly associated with individual hurricane exposure. This study is a first step toward defining what segments of the population are more vulnerable and informing intervention and emergency preparedness efforts. (Disaster Med Public Health Preparedness. 2015;10:325-332).

  9. Experimental study of blast mitigating devices based on combined construction

    NASA Astrophysics Data System (ADS)

    Takayama, K.; Silnikov, M. V.; Chernyshov, M. V.

    2016-09-01

    A robust blast inhibiting bin is the most often used device for damage blast effects suppression. In particular, a top open cylindrical bin significantly reduces a fragmentation effect resulted from a detonation of an explosive device placed inside the bin. However, reduction of blast wave overpressure and impulse by such cylindrical bins is not sufficient [1]. A reasonable alternative to endless increase of height and thickness of robust blast inhibiting bins is a development of destructible inhibitors having no solid elements in their structure and, therefore, excluding secondary fragmentation. So, the family of "Fountain" inhibitors [2,3] localizes and suppresses damaging blast effects due to multiphase working system. The present study is analyzing data obtained in testing of prototypes of new combined inhibitors. Their structure combines robust elements (bottoms, side surfaces) with elements responsible for blast loads reduction due to multi-phase working system (top and low transverse embeddings) and fairings impeding wave propagation in undesirable directions.

  10. Study on sapphire microstructure processing technology based on wet etching

    NASA Astrophysics Data System (ADS)

    Shang, Ying-Qi; Qi, Hong; Ma, Yun-Long; Wu, Ya-Lin; Zhang, Yan; Chen, Jing

    2017-03-01

    Aiming at the problem that sapphire surface roughness is quite large after wet etching in sapphire microstructure processing technology, we optimize the wet etching process parameters, study on the influences of concentration and temperature of etching solution and etching time on the sapphire surface roughness and etching rate, choose different process parameters for the experiment and test and analyze the sapphire results after wet etching. Aiming at test results, we also optimize the process parameters and do experiment. Experimental results show that, after optimizing the parameters of etching solution, surface roughness of etched sapphire is 0.39 nm, effectively with reduced surface roughness, improved light extraction efficiency and meeting the production requirements of high-precision optical pressure sensor.

  11. Cadet Development Through Accelerator-Based Independent Study

    NASA Astrophysics Data System (ADS)

    Pallone, A. K.

    2003-08-01

    The Department of Physics at the United States Military Academy owns and operates an HVEC LC-400 Van de Graaff accelerator. After a few years of limited use, interest among the faculty in the accelerator as a learning tool increased. Four cadets responded to an offer for independent study with the accelerator. The cadets were tasked to measure the diffusion coefficient of boron along tungsten grain boundaries. Two identified objectives were the preparation of the accelerator for the measurements and the development of a coincidence detector to reduce interference from Compton scattered and natural background radiations. How the cadets attacked these objectives, their successes and set backs, and the evolution of their thought process will be presented.

  12. Study on the CO Oxidation over Ceria-Based Nanocatalysts.

    PubMed

    Piumetti, Marco; Andana, Tahrizi; Bensaid, Samir; Russo, Nunzio; Fino, Debora; Pirone, Raffaele

    2016-12-01

    A series of ceria nanocatalysts have been prepared to study the structure dependency of the CO oxidation reaction. The ceria samples with well-defined nanostructures (nanocubes/Ce-NC and nanorods/Ce-NR) have been prepared using the hydrothermal method. Mesoporous ceria (Ce-MES) and ceria synthesized with solution combustion technique (Ce-SCS) have also been prepared for comparison. The lowest CO oxidation temperature has been reached by using ceria nanocubes (Ce-NC). This high activity draws immense contributions from the highly reactive (100) and (110) surfaces of the truncated nanocubes. The Ce-MES and Ce-SCS samples, despite their high surface areas, are unable to outdo the activity of Ce-NC and Ce-NR due to the abundant presence of (111) crystalline planes. This finding confirms the structure sensitivity of CO oxidation reaction catalyzed with ceria.

  13. Student classroom misbehavior: an exploratory study based on teachers' perceptions.

    PubMed

    Sun, Rachel C F; Shek, Daniel T L

    2012-01-01

    This study aimed to examine the conceptions of junior secondary school student misbehaviors in classroom, and to identify the most common, disruptive, and unacceptable student problem behaviors from teachers' perspective. Twelve individual interviews with teachers were conducted. A list of 17 student problem behaviors was generated. Results showed that the most common and disruptive problem behavior was talking out of turn, followed by nonattentiveness, daydreaming, and idleness. The most unacceptable problem behavior was disrespecting teachers in terms of disobedience and rudeness, followed by talking out of turn and verbal aggression. The findings revealed that teachers perceived student problem behaviors as those behaviors involving rule-breaking, violating the implicit norms or expectations, being inappropriate in the classroom settings and upsetting teaching and learning, which mainly required intervention from teachers.

  14. AC Conductivity Studies of Lithium Based Phospho Vanadate Glasses

    NASA Astrophysics Data System (ADS)

    Nagendra, K.; Babu, G. Satish; Reddy, C. Narayana; Gowda, Veeranna

    2011-07-01

    Glasses in the system xLi2SO4-20Li2O-(80-x) [80P2O5-20V2O5] (5⩾x⩾20 mol%) has been prepared by melt quenching method. Dc and ac conductivity has been studied over a wide range of frequency (10 Hz to 10 MHz) and temperature (298 K-523 K). The dc conductivity found to increase with increase of Li2SO4 concentration. The ac conductivities have been fitted to the Almond-West type single power law equation σ(ω) = σ(0)+Aωs where `s' is the power law exponent. The ac conductivity found to increase with increase of Li2SO4 concentration. An attempt is made to elucidate the enhancement of lithium ion conduction in phosphor-vanadate glasses by considering the expansion of network structure.

  15. Studies of Bone Morphogenetic Protein based Surgical Repair

    PubMed Central

    Lo, Kevin W.-H.; Ulery, Bret D.; Ashe, Keshia M.; Laurencin, Cato T.

    2012-01-01

    Over the past several decades, recombinant human bone morphogenetic proteins (rhBMPs) have been the most extensively studied and widely used osteoinductive agents for clinical bone repair. Since rhBMP-2 and rhBMP-7 were approved by the U.S. Food and Drug Administration for certain clinical uses, millions of patients worldwide have been treated with rhBMPs for various musculoskeletal disorders. Current clinical applications include treatment of long bone fracture non-unions, spinal surgeries, and oral maxillofacial surgeries. Considering the growing number of recent publications related to clincal research of rhBMPs, there exists enormous promise for these proteins to be used in bone regenerative medicine. The authors take this opportunity to review the rhBMP literature paying specific attention to the current applications of rhBMPs in bone repair and spine surgery. The prospective future of rhBMPs delivered in combination with tissue engineered scaffolds is also reviewed. PMID:22512928

  16. Study on the CO Oxidation over Ceria-Based Nanocatalysts

    NASA Astrophysics Data System (ADS)

    Piumetti, Marco; Andana, Tahrizi; Bensaid, Samir; Russo, Nunzio; Fino, Debora; Pirone, Raffaele

    2016-03-01

    A series of ceria nanocatalysts have been prepared to study the structure dependency of the CO oxidation reaction. The ceria samples with well-defined nanostructures (nanocubes/Ce-NC and nanorods/Ce-NR) have been prepared using the hydrothermal method. Mesoporous ceria (Ce-MES) and ceria synthesized with solution combustion technique (Ce-SCS) have also been prepared for comparison. The lowest CO oxidation temperature has been reached by using ceria nanocubes (Ce-NC). This high activity draws immense contributions from the highly reactive (100) and (110) surfaces of the truncated nanocubes. The Ce-MES and Ce-SCS samples, despite their high surface areas, are unable to outdo the activity of Ce-NC and Ce-NR due to the abundant presence of (111) crystalline planes. This finding confirms the structure sensitivity of CO oxidation reaction catalyzed with ceria.

  17. Elder mistreatment in urban India: a community based study.

    PubMed

    Chokkanathan, Srinivasan; Lee, Alex E Y

    2005-01-01

    This study examined the extent and correlates of elder mistreatment among 400 community dwelling older adults aged 65 and above in Chennai, India. The prevalence rate of mistreatment was 14%. Chronic verbal abuse was the most common followed by financial abuse and the rate of physical abuse and neglect was similar. Among the mistreated, exactly half of them had experienced more than one type of mistreatment (multifaceted-mistreatment). With the exception of financial abuse, a significantly greater number of women experienced verbal and physical abuse as well as neglect compared to men. Adult children, daughters-in-law, spouses, and sons-in-law were the prominent perpetrators. The mistreated older adults were more depressed and less satisfied with life than those who were not mistreated. Logistic regression analysis revealed gender, social support, and subjective rating of physical health as significant factors associated with abuse.

  18. Proper-Motion Based Kinematics Study of Galactic RR Lyraes

    NASA Astrophysics Data System (ADS)

    Dambis, Andrei K.; Berdnikov, Leonid N.; Rastorguev, Alexei S.; Zabolotskikh, Marina V.

    2016-08-01

    We use the UCAC4 and SDSS proper motions of about 7500 RR Lyrae type variables located within ~10 kpc from the Sun to study the dependence of their velocity ellipsoid on Galactocentric distance in the R G = 3-17 kpc interval. The radial velocity dispersion, σ VR , decreases from ~190 km/s at R G = 3.5-5.5 kpc down to ~100 km/s at R G = 13-15 kpc, and the σ VT /σ VR ratio remains virtually constant (σ VT /σ VR ~0.54-0.64) in the Galactocentric distance interval from R G = 4.5 kpc to R G = 10.5 kpc increasing to ~0.9 both toward the Galactic center and beyond R G = 11 kpc.

  19. Budding yeast colony growth study based on circular granular cell

    NASA Astrophysics Data System (ADS)

    Aprianti, Devi; Khotimah, S. N.; Viridi, S.

    2016-08-01

    Yeast colony growth can be modelled by using circular granular cells, which can grow and produce buds. The bud growth angle can be set to regulate cell budding pattern. Cohesion force, contact force and Stokes force were adopted to accommodate the behaviour and interactions among cells. Simulation steps are divided into two steps, the explicit step is due to cell growing and implicit step for the cell rearrangement. Only in explicit step that time change was performed. In this study, we examine the influence of cell diameter growth time and reproduction time combination toward the growth of cell number and colony formation. We find a commutative relation between the cell diameter growth time and reproduction time to the specific growth rate. The greater value of the multiplication of the parameters, the smaller specific growth rate is obtained. It also shows a linear correlation between the specific growth rate and colony diameter growth rate.

  20. Study of spherical torus based volume neutron source

    SciTech Connect

    Cheng, E.T.; Peng, Yueng Kay Martin

    1998-01-01

    With the worldwide development of fusion power focusing on the design of the International Thermonuclear Experimental Reactor (ITER), developmental strategies for the demonstration fusion power plant (DEMO) are being discussed. A relatively prudent strategy is to construct and operate a small deuterium tritium fuelled volumetric neutron source (VNS) in parallel with ITER. The VNS is to provide, over a period less than 20 years, a relatively high fusion neutron fluence of 6 MW year m2 and wall loading of 1 MW m2 or more, over an accessible blanket test area of more than 10 m2. Such a VNS would complement ITER in testing, developing, and qualifying nuclear technology components, materials, and their combinations for DEMO and future commercial power plants. The effort of this study has established the potential of the spherical tokamak as a credible VNS concept that satisfies the above requirements.

  1. Probabilistic thinking and death anxiety: a terror management based study.

    PubMed

    Hayslip, Bert; Schuler, Eric R; Page, Kyle S; Carver, Kellye S

    2014-01-01

    Terror Management Theory has been utilized to understand how death can change behavioral outcomes and social dynamics. One area that is not well researched is why individuals willingly engage in risky behavior that could accelerate their mortality. One method of distancing a potential life threatening outcome when engaging in risky behaviors is through stacking probability in favor of the event not occurring, termed probabilistic thinking. The present study examines the creation and psychometric properties of the Probabilistic Thinking scale in a sample of young, middle aged, and older adults (n = 472). The scale demonstrated adequate internal consistency reliability for each of the four subscales, excellent overall internal consistency, and good construct validity regarding relationships with measures of death anxiety. Reliable age and gender effects in probabilistic thinking were also observed. The relationship of probabilistic thinking as part of a cultural buffer against death anxiety is discussed, as well as its implications for Terror Management research.

  2. A descriptive hospital based study of children with autism.

    PubMed

    Juneja, M; Mukherjee, S B; Sharma, S

    2005-05-01

    The clinical and neurodevelopmental profile of 51 children with Autistic disorder, from a referral population was studied. A detailed history and examination was undertaken. The development/intelligence quotient and social quotient were assessed. Standard diagnostic tests were applied in children above 2 years of age. Younger children were evaluated with a screening test and re-evaluated at 2 years. It was observed that a correct diagnosis had been made in only 5.8% of children prior to referral. The mean age of presentation was 3.28 years. Ninety-six percent of the autistic children had developmental delay. Qualitative impairment in social interaction and communication was more commonly observed than restricted interests and activities. Forty-seven (92.15%) children were severely autistic and 4 (7.84%) mildly to moderately autistic. All children less than 2 years were confirmed to have Autistic disorder later.

  3. [IR and Raman spectra studies of Rotundine based on DFT].

    PubMed

    Li, Jun-Ping; Zhou, Guang-Ming; Zhang, Li-Jun; Cheng, Hong-Mei; Qin, Hong-Ying

    2014-11-01

    Infrared spectroscopy (IR), the normal Raman spectroscopy (NRS) and the surface enhanced Raman spectroscopy (SERS) in new Ag/Cu nanomaterial of Rotundine were studied in the present paper. The IR and the NRS of Rotundine were calculated by the density functional theory (DFT) using B3LYP/6-311+G(d, p), then the spectral intensity graph of Rotundine were given. The vibrational peaks were assigned comprehensively by the visualization software of Gauss view 5. 0. Rotundine has obvious infrared and Raman vibrational peak in the wave number range of 3 300-2500 and 1 800-600 cm(-1). SnCl2 and PVP was used as capping agent for the silver nanoparticles in SERS of Rotundine. Finally, by using the method of cyclic immersion well dispersed silver nanoparticles was obtained and achieved good enhancement effect. This molecule acquired strong selective enhancement vibration peak, In the wave number ranges of 1 500-1 400 and 1 000-700 cm(-1) the enhancement effect is most obvious. After analyzed, the methylene of this molecule is adsorbed on the silver nanoparticles surface and the angle between the benzene ring and the silver substrate is close to 90 degrees. The theoretically calculated spectra of Rotundine are consistent with the obtained experimental spectra. There are some differences may be due to the interaction forces between molecules and so on. The visualization software displayed the structure characteristics and molecular group vibration of this molecular visually and provided important basis for assigning the vibrational peaks. Rotundine is an important traditional Chinese medicine agent contained in many kinds of sedative drugs. The study provides a strong basis for the rapid, feature and trace identification of Rotundine and also supplies important reference for the biological role of central inhibition of analgesic drugs.

  4. Fracture risk following bariatric surgery: a population-based study.

    PubMed

    Nakamura, K M; Haglind, E G C; Clowes, J A; Achenbach, S J; Atkinson, E J; Melton, L J; Kennel, K A

    2014-01-01

    The effects of bariatric surgery on skeletal health are poorly understood. We found that bariatric surgery patients are more prone to fracture when compared to the general population. While further studies of fracture risk in this population are needed, bone health should be discussed in bariatric surgery clinics. Bariatric surgery is an increasingly common treatment for medically complicated obesity. Adverse skeletal changes after bariatric surgery have been reported, but their clinical importance remains unknown. We hypothesized that bariatric surgery patients are at increased risk of fracture. We conducted a historical cohort study of fracture incidence among 258 Olmsted County, Minnesota, residents who underwent a first bariatric surgery in 1985-2004. Relative fracture risk was expressed as standardized incidence ratios (SIRs), while potential risk factors were evaluated by hazard ratios (HR) obtained from a time-to-fracture regression model. The mean (±SD) body mass index at bariatric surgery was 49.0 ± 8.4 kg/m(2), with an average age of 44 ± 10 years and 82% (212) females. Gastric bypass surgery was performed in 94% of cases. Median follow-up was 7.7 years (range, 6 days to 25 years), during which 79 subjects experienced 132 fractures. Relative risk for any fracture was increased 2.3-fold (95% confidence interval (CI), 1.8-2.8) and was elevated for a first fracture at the hip, spine, wrist, or humerus (SIR, 1.9; 95% CI, 1.1-2.9), as well as for a first fracture at any other site (SIR, 2.5; 95% CI, 2.0-3.2). Better preoperative activity status was associated with a lower age-adjusted risk (HR, 0.4; 95% CI, 0.2-0.8) while prior fracture history was not associated with postoperative fracture risk. Bariatric surgery, which is accompanied by substantial biochemical, hormonal, and mechanical changes, is associated with an increased risk of fracture.

  5. Factors affecting outdoor exposure in winter: population-based study

    NASA Astrophysics Data System (ADS)

    Mäkinen, Tiina M.; Raatikka, Veli-Pekka; Rytkönen, Mika; Jokelainen, Jari; Rintamäki, Hannu; Ruuhela, Reija; Näyhä, Simo; Hassi, Juhani

    2006-09-01

    The extent of outdoor exposure during winter and factors affecting it were examined in a cross-sectional population study in Finland. Men and women aged 25-74 years from the National FINRISK 2002 sub-study ( n=6,591) were queried about their average weekly occupational, leisure-time and total cold exposure during the past winter. The effects of gender, age, area of residence, occupation, ambient temperature, self-rated health, physical activity and education on cold exposure were analysed. The self-reported median total cold exposure time was 7 h/week (8 h men, 6 h women),<1 h/week (2 h men, 0 h women) at work, 4 h/week (5 h men, 4 h women) during leisure time and 1 h/week (1 h men, 1.5 h women) while commuting to work. Factors associated with increased occupational cold exposure among men were: being employed in agriculture, forestry and industry/mining/construction or related occupations, being less educated and being aged 55-64 years. Factors associated with increased leisure-time cold exposure among men were: employment in industry/mining/construction or related occupations, being a pensioner or unemployed, reporting at least average health, being physically active and having college or vocational education. Among women, being a housewife, pensioner or unemployed and engaged in physical activity increased leisure-time cold exposure, and young women were more exposed than older ones. Self-rated health was positively associated with leisure time cold exposure in men and only to a minor extent in women. In conclusion, the subjects reported spending 4% of their total time under cold exposure, most of it (71%) during leisure time. Both occupational and leisure-time cold exposure is greater among men than women.

  6. Poliomyelitis, measles and neonatal tetanus: a hospital based epidemiological study.

    PubMed

    El Shazly, M K; Atta, H Y; Kishk, N A

    1997-01-01

    Vaccine-preventable diseases constitute a major health problem contributing to the morbidity and mortality in many developing countries including Egypt. WHO adopted resolutions to eradicate poliomyelitis by the year 2000, eliminate neonatal tetanus by the year 1995, and reduce measles mortality by 95% and morbidity by 90%, compared to the pre-immunization levels by 1995. Evaluation of preventive programs for these diseases necessitates availability of up to date information on their occurrence. The present study was undertaken to determine the current epidemiological features of poliomyelitis, neonatal tetanus and measles, to identify the trends of these diseases as well as to determine their outcomes and hospital loads. Data about the admitted cases of poliomyelitis, neonatal tetanus and measles were collected from the hospital register of Alexandria fever hospital for five successive years (1992-96). Available information on age, sex, residence, diagnosis, outcome of treatment, dates of admission and discharge were collected. The total number of cases of the three diseases admitted to the hospital during the period 1992-96 were 1406, measles represented 85.4%, neonatal tetanus 13.9% and poliomyelitis 0.7%. The results revealed that in the year 1994 only one case of poliomyelitis was admitted and since then no other cases were reported. The number of measles cases increased gradually in the latter years and about 78% of them were older than five years of age. A significant increase in the age of measles occurrence was observed. A gradual decline in the number of neonatal tetanus cases was observed. These cases were more apt to occur among early neonates but still clustered in certain geographical areas. The results of the study pinpoint the long term impact of the well run program aiming at eradicating poliomyelitis in Alexandria. However, for elimination of neonatal tetanus and controlling measles morbidity, further activities are required including strengthening

  7. Sunlight Exposure and Breast Density: A Population-Based Study

    PubMed Central

    Wu, Sheng-Hui; So, Edwin; Lam, Tsz-ping; Woo, Jean; Yuen, PY; Qin, Ling; Ku, Susanna

    2013-01-01

    Purpose This study aims to assess the association of sunlight exposure with breast cancer risk, measured by the breast density assessed from Tabár's mammographic pattern in Chinese women. Methods A total of 676 premenopausal women were recruited to participate in this study, in which 650 completed a validated sunlight exposure questionnaire via telephone. The mammograms were classified according to Tabár's classification for parenchyma, and patterns IV & V and I, II & III indicated respectively high and low risk mammographic patterns for breast cancer. The odds ratios (OR) and 95% confidence intervals (CIs) for sun exposure-related variables were estimated using unconditional logistic regression with adjustment for potential confounders. Results Among 646 participants, women with high breast cancer risk (Tabár's patterns IV &V) had less hours spent in the sun than those with low risk (I, II & III) at any age stage. A higher level of sunlight exposure was associated with a significantly lower risk having high risk Tabár's pattern. Women aged 40 to 44 years who were in the highest tertile of lifetime total hours spent in the sun had a multi-adjusted OR of 0.41 (95% CI, 0.18-0.92; p for trend=0.03) compared with those in the lowest tertile (>2.19 hr/day vs. <1.32 hr/day). For hours spent in the sun across the ages of 6 to 12 years, the comparable OR was 0.37 (95% CI, 0.15-0.91; p for trend=0.03). Conclusion These findings suggest that higher sunlight exposure is related to a lower risk of having high risk breast density pattern in premenopausal women. Our results also suggest the most relevant period of exposure is during earlier life. PMID:23843849

  8. Trauma Boot Camp: A Simulation-Based Pilot Study

    PubMed Central

    Moftakhar, Yasmin; Dobbins IV, Arthur L; Khan, Ramisha; Dasgupta, Rahul; Blanda, Rachel; Marchand, Tiffany; Ahmed, Rami

    2016-01-01

    Introduction: Interns are often unprepared to effectively communicate in the acute trauma setting. Despite the many strengths of the Advanced Trauma Life Support (ATLS) program, the main shortcoming within the course is the deficiency of teamwork and leadership training. In this study, we describe the creation of an interdisciplinary boot camp in which interns' basic trauma knowledge, level of confidence, and teamwork skills are assessed. Methods: We designed a one-day, boot camp curriculum for interns of various specialties with the purpose of improving communication and teamwork skills for effective management of acute trauma patients. Our curriculum consisted of a one-day, twelve-hour experience, which included trauma patient simulations, content expert lectures, group discussion of video demonstrations, and skill development workstations. Baseline and acquired knowledge were assessed through the use of confidence surveys, cognitive questionnaires, and a validated evaluation tool of teamwork and leadership skills for trauma Results: Fifteen interns entered the boot camp with an overall confidence score of 3.2 (1-5 scale) in the management of trauma cases. At the culmination of the study, there was a significant increase in the overall confidence level of interns in role delegation, leadership, Crisis Resource Management (CRM) principles, and in the performance of primary and secondary surveys. No significant changes were seen in determining and effectively using the Glasgow Coma Scale, Orthopedic splinting/reduction skills, and effective use of closed-loop communication. Conclusion: An intensive one-day trauma boot camp demonstrated significant improvement in self-reported confidence of CRM concepts, role delegation, leadership, and performance of primary and secondary surveys. Despite the intensive curriculum, there was no significant improvement in overall teamwork and leadership performance during simulated cases. Our boot camp curriculum offers educators a

  9. Resampling-Based Approaches to Study Variation in Morphological Modularity

    PubMed Central

    Fruciano, Carmelo; Franchini, Paolo; Meyer, Axel

    2013-01-01

    Modularity has been suggested to be connected to evolvability because a higher degree of independence among parts allows them to evolve as separate units. Recently, the Escoufier RV coefficient has been proposed as a measure of the degree of integration between modules in multivariate morphometric datasets. However, it has been shown, using randomly simulated datasets, that the value of the RV coefficient depends on sample size. Also, so far there is no statistical test for the difference in the RV coefficient between a priori defined groups of observations. Here, we (1), using a rarefaction analysis, show that the value of the RV coefficient depends on sample size also in real geometric morphometric datasets; (2) propose a permutation procedure to test for the difference in the RV coefficient between a priori defined groups of observations; (3) show, through simulations, that such a permutation procedure has an appropriate Type I error; (4) suggest that a rarefaction procedure could be used to obtain sample-size-corrected values of the RV coefficient; and (5) propose a nearest-neighbor procedure that could be used when studying the variation of modularity in geographic space. The approaches outlined here, readily extendable to non-morphometric datasets, allow study of the variation in the degree of integration between a priori defined modules. A Java application – that will allow performance of the proposed test using a software with graphical user interface – has also been developed and is available at the Morphometrics at Stony Brook Web page (http://life.bio.sunysb.edu/morph/). PMID:23874956

  10. A population based study of drowning in Canada.

    PubMed

    Clemens, Tessa; Tamim, Hala; Rotondi, Michael; Macpherson, Alison K

    2016-07-13

    Although water-related fatality rates have changed over time, the epidemiology of drowning in Canada has not recently been examined. In spite of the evidence supporting varying drowning death rates by age, information on how characteristics of drowning incidents differ by age group remains limited. The primary objective of this study was to examine the epidemiology of drowning in Canada. A secondary objective was to describe the characteristics of these drowning incidents as they vary by age group. A retrospective descriptive analysis was conducted using data that were collected for incidents occurring in Canada between January 1, 2008 and December 31, 2012. The main outcome variable was a water-related fatality, in the majority of cases (94 %) the primary cause of death was drowning. Age specific frequencies, proportions and rates per 100,000 population were calculated and compared among six age groups. There were 2392 unintentional water-related fatalities identified in Canada between 2008 and 2012. Death rates (per 100,000) varied by age group 0-4 (1.05), 5-14 (0.57), 15-19 (1.27), 20-34 (1.70), 35-64 (1.44), 65+ (1.74). The male to female ratio was 5:1. Differences in the characteristics of drowning by age group were identified across: sex, body of water, urban versus rural location, time of year, activity type, purpose of activity, alcohol involvement, personal flotation device use, accompaniment, and whether a rescue was attempted. The study results suggest that there may be a need for drowning prevention strategies that are tailored to specific age groups. Rural areas in Canada may also benefit from targeted drowning prevention.

  11. Hodgkin lymphoma in Tyrol-a population-based study.

    PubMed

    Fong, Dominic; Steurer, Michael; Greil, Richard; Gunsilius, Eberhard; Spizzo, Gilbert; Gastl, Guenther; Tzankov, Alexandar

    2009-05-01

    We aimed to analyze the epidemiology, clinical characteristics, and outcome of patients with Hodgkin lymphoma (HL) diagnosed in Tyrol. All patients with newly diagnosed HL between 1993 and 2005 were included in this study. Among the 158 cases included, nodular lymphocytic predominant HL (nodular paragranuloma) was identified in ten cases (6%) whereas the majority of patients had classical Hodgkin lymphoma. Age (p < 0.01), sex (p = 0.03), risk groups according to the German Hodgkin Study Group stratification (p < 0.01), and bone marrow infiltration (p < 0.01) were of prognostic significance considering overall survival (OS) whereas histological subtype and bulky disease were not. The 5- and 10-year OS rates for the total group were 89% and 85%, respectively. Notably, in patients with advanced-stage HL (n = 49), combined modality treatment resulted in significantly better OS than chemotherapy alone (p = 0.01). Three patients developed a second hematological malignancy and one patient developed breast cancer. However, five patients (3%) had a malignant hematological disorder before occurrence of HL. Concerning treatment-related toxicity, bleomycin-associated lung toxicity was observed in six (4%) patients and five (3%) developed lethal treatment-related infectious complications. Our results provide evidence that the incidence rate of HL in Tyrol is comparable to other Western countries. Modern risk-adapted treatment results in excellent long-term prognosis but may be complicated by serious nonhematological side effects, in particular, infections and bleomycin-induced lung toxicity. Furthermore, 3% of HL patients had an antecedent malignant hematological disease before occurrence of HL.

  12. Soil Studies: Applying Acid-Base Chemistry to Environmental Analysis.

    ERIC Educational Resources Information Center

    West, Donna M.; Sterling, Donna R.

    2001-01-01

    Laboratory activities for chemistry students focus attention on the use of acid-base chemistry to examine environmental conditions. After using standard laboratory procedures to analyze soil and rainwater samples, students use web-based resources to interpret their findings. Uses CBL probes and graphing calculators to gather and analyze data and…

  13. Proficiency-Based Admission Standards Study (PASS). Revised.

    ERIC Educational Resources Information Center

    Conley, David T.; And Others

    This report presents the framework for a legislatively mandated proficiency-based approach to admissions at Oregon's eight public baccalaureate-granting institutions. The goal of the report is to present a systems-level description of why and how a proficiency-based admissions system should operate. Part 1 considers the implications of the…

  14. Soil Studies: Applying Acid-Base Chemistry to Environmental Analysis.

    ERIC Educational Resources Information Center

    West, Donna M.; Sterling, Donna R.

    2001-01-01

    Laboratory activities for chemistry students focus attention on the use of acid-base chemistry to examine environmental conditions. After using standard laboratory procedures to analyze soil and rainwater samples, students use web-based resources to interpret their findings. Uses CBL probes and graphing calculators to gather and analyze data and…

  15. A Study of Multimedia Annotation of Web-Based Materials

    ERIC Educational Resources Information Center

    Hwang, Wu-Yuin; Wang, Chin-Yu; Sharples, Mike

    2007-01-01

    Web-based learning has become an important way to enhance learning and teaching, offering many learning opportunities. A limitation of current Web-based learning is the restricted ability of students to personalize and annotate the learning materials. Providing personalized tools and analyzing some types of learning behavior, such as students'…

  16. Competency-Based Learning Packages--A Case Study

    ERIC Educational Resources Information Center

    Murray, Norman J. M.

    1976-01-01

    Nontraditional, external degree components of the IPCD (Institute for Personal Career Development) packages are competency based in anticipation of the fulfillment of personal and career objectives rather than for the fulfillment of traditional classroom objectives. (ABM)

  17. STUDIES ON THE PHYSIOLOGICAL BASES OF MORPHOGENESIS IN FUNGI

    PubMed Central

    Nickerson, Walter J.; Edwards, George A.

    1949-01-01

    The interconversions of mycelial and yeast-like forms (M ⇌ Y) in Blastomyces dermatitidis and in Blastomyces brasiliensis are characterized as examples of thermal dimorphism since the phenomena are apparently dependent only on the temperature of incubation of these two species. The change in morphology consequent upon Y → M conversion is considered to result from the selective inhibition of cell division, without the simultaneous inhibition of growth. Such selective inhibition is viewed in a wider context as an example of the differential operation of the physicochemical apparatus of the cell in the control of form development by an organism. To analyze this differential operation, which is here dependent only on temperature, we have studied the effect of temperature on oxygen consumption by each of the dimorphic forms. In the absence of external substrate the yeast forms consume 5 to 6 times more oxygen per unit dry weight than do the M forms.The Y forms exhibit an exogenous oxidation of acetate and of glucose, as well as an oxidative assimilation of these substrates, whereas the M forms exhibit no exogenous metabolism in either a resting or starved condition. A study of the effect of a wide range of temperatures on oxygen consumption by the M forms indicates the operation of two rate-limiting processes: (a) one with an activation energy of 13,250 calories/gm. molecule over the range 5–30°, and (b) reversible enzyme inactivation; the latter process assuming importance in the higher temperature range. On abrupt, large changes in temperature the balance between these two rate-limiting reactions (which it is suggested characterizes the steady state) is apparently disrupted as a result of a lag in the assumption of a rate of reversible enzyme inactivation characteristic of the new temperature. This disruption of balance is evidenced in overshoot phenomena. The effect of an analogous disruption of balance, and of increasing enzymic inactivation; on a competition

  18. Cancer incidence among Danish seafarers: a population based cohort study

    PubMed Central

    Kaerlev, L; Hansen, J; Hansen, H; Nielsen, P

    2005-01-01

    Aims: Seafarers aboard oil and chemical tankers may be exposed to many chemicals, including substances like benzene that are known to be carcinogenic. Other seafarers are exposed to engine exhaust, different oil products, and chemicals used aboard and some years ago asbestos was also used extensively in ships. The aim of this study was to study cancer morbidity among Danish seafarers in relation to type of ship and job title. Methods: A cohort of all Danish seafarers during 1986–1999 (33 340 men; 11 291 women) registered by the Danish Maritime Authority with an employment history was linked with the nationwide Danish Cancer Registry and followed up for cancer until the end of 2002. The number of person years at risk was 517 518. Standardised incidence ratios (SIR) were estimated by use of the corresponding national rates. Results: The SIR of all cancers combined was higher than expected: 1.26 (95% CI 1.19 to 1.32) for men and 1.07 (95% CI 0.95 to 1.20) for women. This was mainly due to an excess of cancer of the larynx, lung, tongue, mouth, pharynx, oesophagus, pancreas, kidney, urinary bladder, colon, and bone as well as skin melanomas among men (the three latter borderline significantly increased), and an excess of cancer of the lung, rectum, and cervix uteri among women. The differences in risk pattern for lung cancer between the different job categories among men ranged in terms of SIR from 1.2 (95% CI 0.9 to 1.7) (engine officers) to 2.3 (1.6 to 3.3) (engine room crew), and 4.1 (2.1 to 7.4) among maintenance crew. Non-officers had a 1.5 times higher lung cancer risk than officers. No increased occurrence of all lymphatic and haematopoietic malignancies combined was found for employees on tankers, but the number of cases was limited to a total of 7. Conclusions: Danish seafarers, especially men, face an increased overall cancer risk, in particular a risk for lung cancer and other tobacco associated cancers. PMID:16234401

  19. [Three-dimensional endoscopic endonasal study of skull base anatomy].

    PubMed

    Abarca-Olivas, Javier; Monjas-Cánovas, Irene; López-Álvarez, Beatriz; Lloret-García, Jaime; Sanchez-del Campo, Jose; Gras-Albert, Juan Ramon; Moreno-López, Pedro

    2014-01-01

    Training in dissection of the paranasal sinuses and the skull base is essential for anatomical understanding and correct surgical techniques. Three-dimensional (3D) visualisation of endoscopic skull base anatomy increases spatial orientation and allows depth perception. To show endoscopic skull base anatomy based on the 3D technique. We performed endoscopic dissection in cadaveric specimens fixed with formalin and with the Thiel technique, both prepared using intravascular injection of coloured material. Endonasal approaches were performed with conventional 2D endoscopes. Then we applied the 3D anaglyph technique to illustrate the pictures in 3D. The most important anatomical structures and landmarks of the sellar region under endonasal endoscopic vision are illustrated in 3D images. The skull base consists of complex bony and neurovascular structures. Experience with cadaver dissection is essential to understand complex anatomy and develop surgical skills. A 3D view constitutes a useful tool for understanding skull base anatomy. Copyright © 2012 Sociedad Española de Neurocirugía. Published by Elsevier España. All rights reserved.

  20. Inverse field-based approach for simultaneous B₁ mapping at high fields - a phantom based study.

    PubMed

    Jin, Jin; Liu, Feng; Zuo, Zhentao; Xue, Rong; Li, Mingyan; Li, Yu; Weber, Ewald; Crozier, Stuart

    2012-04-01

    Based on computational electromagnetics and multi-level optimization, an inverse approach of attaining accurate mapping of both transmit and receive sensitivity of radiofrequency coils is presented. This paper extends our previous study of inverse methods of receptivity mapping at low fields, to allow accurate mapping of RF magnetic fields (B(1)) for high-field applications. Accurate receive sensitivity mapping is essential to image domain parallel imaging methods, such as sensitivity encoding (SENSE), to reconstruct high quality images. Accurate transmit sensitivity mapping will facilitate RF-shimming and parallel transmission techniques that directly address the RF inhomogeneity issue, arguably the most challenging issue of high-field magnetic resonance imaging (MRI). The inverse field-based approach proposed herein is based on computational electromagnetics and iterative optimization. It fits an experimental image to the numerically calculated signal intensity by iteratively optimizing the coil-subject geometry to better resemble the experiments. Accurate transmit and receive sensitivities are derived as intermediate results of the optimization process. The method is validated by imaging studies using homogeneous saline phantom at 7T. A simulation study at 300MHz demonstrates that the proposed method is able to obtain receptivity mapping with errors an order of magnitude less than that of the conventional method. The more accurate receptivity mapping and simultaneously obtained transmit sensitivity mapping could enable artefact-reduced and intensity-corrected image reconstructions. It is hoped that by providing an approach to the accurate mapping of both transmit and receive sensitivity, the proposed method will facilitate a range of applications in high-field MRI and parallel imaging. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. A DFT study of oxygen dissociation on platinum based nanoparticles.

    PubMed

    Jennings, Paul C; Aleksandrov, Hristiyan A; Neyman, Konstantin M; Johnston, Roy L

    2014-01-21

    Density functional theory calculations are performed on 38 and 79 metal atom truncated octahedron clusters to study oxygen dissociation as a model for the initial stage of the oxygen reduction reaction. Pure platinum and alloyed platinum-titanium core-shell systems are investigated. It is found that barrierless oxygen dissociation occurs on the (111) facet of the pure platinum clusters. A barrier of ~0.3 eV is observed on the (100) facet. For the alloyed cluster, dissociation barriers are found on both facets, typically ~0.6 eV. The differences between the two systems are attributed to the ability of oxygen to distort the (111) surface of the pure platinum clusters. We show that flexibility of the platinum shell is crucial in promotion of fast oxygen dissociation. However, the titanium core stabilises the platinum shell upon alloying, resulting in a less easily distortable surface. Therefore, whilst an alloyed platinum-titanium electrocatalyst has certain advantages over the pure platinum electrocatalyst, we suggest alloying with a more weakly interacting metal will be beneficial for facilitating oxygen dissociation.

  2. Integrated Genome-Based Studies of Shewanella Ecophysiology

    SciTech Connect

    Spormann, Alfred

    2011-07-12

    We have constructed in-frame deletions of 7 of the 10 PAS-GGDEF-EAL proteins in Shewanella oneidensis MR-1. We are currently in the process of characterizing the deletion mutants under a wide range of growth conditions. In addition to characterizing growth, we will also examine the biofilm formation of the deletion mutants. In addition to the genetic analyses of the mutants, we are also interested in comparing the activities of the various PAS-GGDEF-EAL proteins. Proteins containing PAS, GGDEF and EAL amino acid sequence motifs may play an important role in regulating c-di-GMP signaling in response to environmental conditions. A genetic and biochemical analysis into the roles of these proteins is underway. PDE activity was observed for several PAS-GGDEF-EAL proteins. One of these proteins, SO0427, also demonstrates possible DGC activity in vitro. Currently, we are studying the growth, motility and biofilm formation characteristics of deletion mutants, as well as the activity of the purified proteins.

  3. Distally Based Iliotibial Band Flap: Anatomic Study with Surgical Considerations.

    PubMed

    Wong, Victor W; Higgins, James P

    2016-09-01

    Background Reconstruction of high-risk fascia, tendon, or ligament defects may benefit from vascularized tissue. The iliotibial band (ITB), a thick fibrous tract of connective tissue, serves as a potential donor site for free tissue transfer but its blood supply has not been thoroughly investigated. The aim of this anatomical study was to investigate the vascular supply to the distal ITB and its role as a free fascial flap. Methods We dissected 16 fresh-frozen cadaveric legs and injected latex into the superolateral geniculate artery (SLGA). A distal ITB fascial flap was designed and measurements were taken for flap dimensions, pedicle length and size, and SLGA perfusion territory. Results The SLGA perfused 11.5 ± 2.3 cm of distal ITB (proximal to the lateral femoral epicondyle) and provided 6.4 ± 0.7cm of pedicle length to the ITB flap. Conclusions Chimeric options to include bone (from the lateral femoral condyle), cartilage (from the lateral femoral trochlea), muscle (from vastus lateralis or biceps femoris), and skin are possible. Surgical harvest techniques are proposed, including preservation of ITB insertions to minimize lateral knee instability. Clinical validation is needed to determine the role of the distal ITB free fascial flap in reconstructive microsurgery. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  4. Defining habitat covariates in camera-trap based occupancy studies.

    PubMed

    Niedballa, Jürgen; Sollmann, Rahel; bin Mohamed, Azlan; Bender, Johannes; Wilting, Andreas

    2015-11-24

    In species-habitat association studies, both the type and spatial scale of habitat covariates need to match the ecology of the focal species. We assessed the potential of high-resolution satellite imagery for generating habitat covariates using camera-trapping data from Sabah, Malaysian Borneo, within an occupancy framework. We tested the predictive power of covariates generated from satellite imagery at different resolutions and extents (focal patch sizes, 10-500 m around sample points) on estimates of occupancy patterns of six small to medium sized mammal species/species groups. High-resolution land cover information had considerably more model support for small, patchily distributed habitat features, whereas it had no advantage for large, homogeneous habitat features. A comparison of different focal patch sizes including remote sensing data and an in-situ measure showed that patches with a 50-m radius had most support for the target species. Thus, high-resolution satellite imagery proved to be particularly useful in heterogeneous landscapes, and can be used as a surrogate for certain in-situ measures, reducing field effort in logistically challenging environments. Additionally, remote sensed data provide more flexibility in defining appropriate spatial scales, which we show to impact estimates of wildlife-habitat associations.

  5. Mechanical Ventilation Boot Camp: A Simulation-Based Pilot Study

    PubMed Central

    Yee, Jennifer; Fuenning, Charles; George, Richard; Hejal, Rana; Haines, Nhi; Dunn, Diane; Gothard, M. David; Ahmed, Rami A.

    2016-01-01

    Objectives. Management of mechanically ventilated patients may pose a challenge to novice residents, many of which may not have received formal dedicated critical care instruction prior to starting their residency training. There is a paucity of data regarding simulation and mechanical ventilation training in the medical education literature. The purpose of this study was to develop a curriculum to educate first-year residents on addressing and troubleshooting ventilator alarms. Methods. Prospective evaluation was conducted of seventeen residents undergoing a twelve-hour three-day curriculum. Residents were assessed using a predetermined critical action checklist for each case, as well as pre- and postcurriculum multiple-choice cognitive knowledge questionnaires and confidence surveys. Results. Significant improvements in cognitive knowledge, critical actions, and self-reported confidence were demonstrated. The mean change in test score from before to after intervention was +26.8%, and a median score increase of 25% was noted. The ARDS and the mucus plugging cases had statistically significant improvements in critical actions, p < 0.001. A mean increase in self-reported confidence was realized (1.55 to 3.64), p = 0.049. Conclusions. A three-day simulation curriculum for residents was effective in increasing competency, knowledge, and confidence with ventilator management. PMID:26949545

  6. Defining habitat covariates in camera-trap based occupancy studies

    PubMed Central

    Niedballa, Jürgen; Sollmann, Rahel; Mohamed, Azlan bin; Bender, Johannes; Wilting, Andreas

    2015-01-01

    In species-habitat association studies, both the type and spatial scale of habitat covariates need to match the ecology of the focal species. We assessed the potential of high-resolution satellite imagery for generating habitat covariates using camera-trapping data from Sabah, Malaysian Borneo, within an occupancy framework. We tested the predictive power of covariates generated from satellite imagery at different resolutions and extents (focal patch sizes, 10–500 m around sample points) on estimates of occupancy patterns of six small to medium sized mammal species/species groups. High-resolution land cover information had considerably more model support for small, patchily distributed habitat features, whereas it had no advantage for large, homogeneous habitat features. A comparison of different focal patch sizes including remote sensing data and an in-situ measure showed that patches with a 50-m radius had most support for the target species. Thus, high-resolution satellite imagery proved to be particularly useful in heterogeneous landscapes, and can be used as a surrogate for certain in-situ measures, reducing field effort in logistically challenging environments. Additionally, remote sensed data provide more flexibility in defining appropriate spatial scales, which we show to impact estimates of wildlife-habitat associations. PMID:26596779

  7. Tryptophan-based Fluorophores for Studying Protein Conformational Changes

    PubMed Central

    Talukder, Poulami; Chen, Shengxi; Liu, C. Tony; Baldwin, Edwin A.; Benkovic, Stephen J.; Hecht, Sidney M.

    2014-01-01

    With the continuing interest in deciphering the interplay between protein function and conformational changes, small fluorescence probes will be especially useful for tracking changes in the crowded protein interior space. Presently, we describe the potential utility of six unnatural amino acid fluorescence donors structurally related to tryptophan and show how they can be efficiently incorporated into a protein as fluorescence probes. We also examine the various photophysical properties of the new Trp analogues, which are significantly redshifted in their fluorescence spectra relative to tryptophan. In general, the Trp analogues were well tolerated when inserted into E. coli DHFR, and did not perturb enzyme activity, although substitution for Trp22 did result in a diminution in DHFR activity. Further, it was demonstrated that D and E at position 37 formed efficient FRET pairs with acridon-2-ylalanine (Acd) at position 17. The same was also true for a DHFR construct containing E at position 79 and Acd at position 17. Together, these findings demonstrate that these tryptophan analogues can be introduced into DHFR with minimal disruption of function, and that they can be employed for the selective study of targeted conformational or electrostatic changes in proteins, even in the presence of unmodified tryptophans. PMID:25284250

  8. Solar cells based on GaAs: Thermal behavior study

    NASA Astrophysics Data System (ADS)

    Giudicelli, Emmanuel; Martaj, Nadia; Dollet, Alain; Perona, Arnaud; Pincemin, Sandrine; Cuminal, Yvan

    2015-09-01

    Current CPV electricity costs are still higher than those of conventional PV (thin films or silicon). This is due to additional components (tracker, Fresnel lens, optical guide…) required for CPV and to a lesser extent, to the very high price of III-V multi-junction solar cells. One way to lower CPV costs is to reduce the size of solar cells and operate at higher concentration [1]. One of the main potential limitations for the use of PV cells at very high solar concentration is cell overheating. The goal of this work is to study and better understand the thermal behavior of PV cells in high solar concentrations conditions (˜ 2000 suns). For that purpose, we have designed and prepared PV cells with platinum resistors included. Temperature measurements performed on these cells in real solar concentration conditions have allowed us to validate thermal simulations of our devices that could be used to optimize the thermal management of the cell under high concentration.

  9. AC Conductivity Studies of Lithium Based Phospho Vanadate Glasses

    SciTech Connect

    Nagendra, K.; Babu, G. Satish; Gowda, Veeranna; Reddy, C. Narayana

    2011-07-15

    Glasses in the system xLi{sub 2}SO{sub 4}-20Li{sub 2}O-(80-x) [80P{sub 2}O{sub 5}-20V{sub 2}O{sub 5}](5{>=}x{>=}20 mol%) has been prepared by melt quenching method. Dc and ac conductivity has been studied over a wide range of frequency (10 Hz to 10 MHz) and temperature (298 K-523 K). The dc conductivity found to increase with increase of Li{sub 2}SO{sub 4} concentration. The ac conductivities have been fitted to the Almond-West type single power law equation {sigma}({omega}) = {sigma}(0)+A{omega}{sup s} where 's' is the power law exponent. The ac conductivity found to increase with increase of Li{sub 2}SO{sub 4} concentration. An attempt is made to elucidate the enhancement of lithium ion conduction in phosphor-vanadate glasses by considering the expansion of network structure.

  10. Health Literacy in Taiwan: A Population-Based Study.

    PubMed

    Duong, Van Tuyen; Lin, I-Feng; Sorensen, Kristine; Pelikan, Jürgen M; Van Den Broucke, Stephan; Lin, Ying-Chin; Chang, Peter Wushou

    2015-11-01

    Data on health literacy (HL) in the population is limited for Asian countries. This study aimed to test the validity of the Mandarin version of the European Health Literacy Survey Questionnaire (HLS-EU-Q) for use in the general public in Taiwan. Multistage stratification random sampling resulted in a sample of 2989 people aged 15 years and above. The HLS-EU-Q was validated by confirmatory factor analysis with excellent model data fit indices. The general HL of the Taiwanese population was 34.4 ± 6.6 on a scale of 50. Multivariate regression analysis showed that higher general HL is significantly associated with the higher ability to pay for medication, higher self-perceived social status, higher frequency of watching health-related TV, and community involvement but associated with younger age. HL is also associated with health status, health behaviors, and health care accessibility and use. The HLS-EU-Q was found to be a useful tool to assess HL and its associated factors in the general population.

  11. Mortality of congenital osteochondrodysplasias: a nationwide registry-based study.

    PubMed

    Morales-Piga, Antonio; Alonso-Ferreira, Verónica; Villaverde-Hueso, Ana; Posada de la Paz, Manuel; López-Abente, Gonzalo

    2013-07-01

    Osteochondrodysplasias are a heterogeneous group of more than 200 entities, characterized by abnormalities of cartilage, bone growth, and skeletal development. The aim of this study was to assess temporal and spatial changes in overall mortality due to these disorders in Spain, using data from a nationwide registry. Annual deaths showing osteochondrodysplasias as the underlying cause of death were selected using the International Classification of Diseases-9th revision (ICD-9) codes for the period 1981 through 1998, and ICD-10 codes for the period 1999 through 2008. Age-adjusted mortality rates were calculated by sex, and geographic analysis was performed by municipality. A total of 679 deaths were recorded (53% men). Age-adjusted mortality rates went from 0.09 (0.06, 0.12) per 100,000 population in 1981 to 0.05 (0.03, 0.08) per 100,000 population in 2008. A changing trend in the age-standardized mortality rate was in evidence, with an annual increase of 2.4% (-0.4, 5.2) from 1981 to 1994, and an annual decrease of -7.3% (-10.9, -3.5) from 1995 onwards. Geographic analysis showed some places situated in the west and south of Spain with greater risk of mortality. There is a need to identify risk factors and to increase overall knowledge about the life expectancy and epidemiology of osteochondrodysplasias. Copyright © 2013 Wiley Periodicals, Inc.

  12. Water - Based TiO2 Suspensions: A Raman Study

    NASA Astrophysics Data System (ADS)

    Rangel, Roberto; Chipara, Dorina; Yust, Brian; Padilla, Desiree; Chipara, Mircea

    The antibacterial features of TiO2 are under scrutiny due to the UV radiation, which contributes to the generation of reactive oxygen species, mainly in water environments. A study of TiO2 suspensions in water and broth is reported. TiO2 has a low solubility in water. TiO2 (anatase), with average diameter of 15 nm from Nanostructured & Amorphous Materials, Inc. has been added to the fluid (water, broth) and the mixture was stirred for 1-10 h, followed by a 10-60 minutes sonication. The suspension was left to sediment for 1 day before measurements. Quasistable suspensions of TiO2 in water and broth were investigated by Raman spectroscopy using a Renishaw InVia spectrometer operating at 532 and 785 nm. The spectra of the nanofiller have been simulated by a collection of Breit-Wigner Fano line shapes and the effect of the preparation conditions (stirring and sonication time) on the parameters of Raman lines are reported. The differences are explained by observing that the sonication destroys the agglomerates of anatase resulting in a better dispersion of nanoparticles and consequently a longer sedimentation time. Sample preparation/storage have been done both under dark and UV light conditions.

  13. Infrared thermography based studies on mobile phone induced heating

    NASA Astrophysics Data System (ADS)

    Lahiri, B. B.; Bagavathiappan, S.; Soumya, C.; Jayakumar, T.; Philip, John

    2015-07-01

    Here, we report the skin temperature rise due to the absorption of radio frequency (RF) energy from three handheld mobile phones using infrared thermography technique. Experiments are performed under two different conditions, viz. when the mobile phones are placed in soft touch with the skin surface and away from the skin surface. Additionally, the temperature rise of mobile phones during charging, operation and simultaneous charging and talking are monitored under different exposure conditions. It is observed that the temperature of the cheek and ear regions monotonically increased with time during the usage of mobile phones and the magnitude of the temperature rise is higher for the mobile phone with higher specific absorption rate. The increase in skin temperature is higher when the mobile phones are in contact with the skin surface due to the combined effect of absorption of RF electromagnetic power and conductive heat transfer. The increase in the skin temperature in non-contact mode is found to be within the safety limit of 1 °C. The measured temperature rise is in good agreement with theoretical predictions. The empirical equation obtained from the temperature rise on the cheek region of the subjects correlates well with the specific absorption rate of the mobile phones. Our study suggests that the use of mobile phones in non-contact mode can significantly lower the skin temperature rise during its use and hence, is safer compared to the contact mode.

  14. Case studies of ecosystem-based approaches to remediation

    SciTech Connect

    Trimble, K.

    1996-12-31

    Applications of the ecological sciences to site remediation have becoming increasingly common, as objectives have expanded from surface stabilization and aesthetic improvement to actual ecosystem reconstruction. In the fields of surface mining reclamation, specific techniques are often applied to common problems such as slope instability and erosion. The influence of larger scale physical and biological pressures on a site from the surrounding ecosystem, such as vegetation succession, is usually ignored. These processes affect the success of reclamation techniques, the management effort required to achieve success, the appropriateness of choices where alternative techniques exist, and the long term ecosystem sustainability. We stress a need for design approaches that examine the broad ecological context of site specific projects. Using cases study examples, we discuss cost-effective considerations including successional trajectory, bioregional wildlife and vegetation management criteria, and large scale biodiversity targets. Such considerations are used in establishing goals for site specific projects, and as tools in choosing appropriate techniques. In one example, the rehabilitation design for a limestone quarry in southern Ontario addressed regional aquatic habitat requirements, wildlife and forest community targets, and bioregional populations of internationally significant species, while at the same time minimizing approval and maintenance issues.

  15. Solar cells based on GaAs: Thermal behavior study

    NASA Astrophysics Data System (ADS)

    Giudicelli, Emmanuel; Martaj, Nadia; Bennacer, Rachid; Dollet, Alain; Perona, Arnaud; Pincemin, Sandrine; Cuminal, Yvan

    2016-03-01

    Current CPV electricity costs are still higher than those of conventional PV (thin films or silicon). This is due to additional components (tracker, Fresnel lens, optical guide…) required for CPV and to a lesser extent, to the very high price of III-V multi-junction solar cells. One way to lower CPV costs is to reduce the size of solar cells and operate at higher concentration [1]. One of the main potential limitations for the use of PV cells at very high solar concentration is cell overheating. The goal of this work is to study and better understand the thermal behavior of PV cells in high solar concentrations conditions (˜ 2000 suns). For that purpose, we have designed and prepared PV cells with platinum resistors included. Temperature measurements performed on these cells in real solar concentration conditions have allowed us to validate thermal simulations of our devices that could be used to optimize the thermal management of the cell under high concentration. At the request of the authors of the paper, an updated version of this article was published on 31 March 2016. In the original article supplied to AIP Publishing an author was omitted as well as a credit line on the last page. These errors have been corrected in the updated republished article.

  16. A global benchmark study using affinity-based biosensors

    PubMed Central

    Rich, Rebecca L.; Papalia, Giuseppe A.; Flynn, Peter J.; Furneisen, Jamie; Quinn, John; Klein, Joshua S.; Katsamba, Phini S.; Waddell, M. Brent; Scott, Michael; Thompson, Joshua; Berlier, Judie; Corry, Schuyler; Baltzinger, Mireille; Zeder-Lutz, Gabrielle; Schoenemann, Andreas; Clabbers, Anca; Wieckowski, Sebastien; Murphy, Mary M.; Page, Phillip; Ryan, Thomas E.; Duffner, Jay; Ganguly, Tanmoy; Corbin, John; Gautam, Satyen; Anderluh, Gregor; Bavdek, Andrej; Reichmann, Dana; Yadav, Satya P.; Hommema, Eric; Pol, Ewa; Drake, Andrew; Klakamp, Scott; Chapman, Trevor; Kernaghan, Dawn; Miller, Ken; Schuman, Jason; Lindquist, Kevin; Herlihy, Kara; Murphy, Michael B.; Bohnsack, Richard; Andrien, Bruce; Brandani, Pietro; Terwey, Danny; Millican, Rohn; Darling, Ryan J.; Wang, Liann; Carter, Quincy; Dotzlaf, Joe; Lopez-Sagaseta, Jacinto; Campbell, Islay; Torreri, Paola; Hoos, Sylviane; England, Patrick; Liu, Yang; Abdiche, Yasmina; Malashock, Daniel; Pinkerton, Alanna; Wong, Melanie; Lafer, Eileen; Hinck, Cynthia; Thompson, Kevin; Primo, Carmelo Di; Joyce, Alison; Brooks, Jonathan; Torta, Federico; Bagge Hagel, Anne Birgitte; Krarup, Janus; Pass, Jesper; Ferreira, Monica; Shikov, Sergei; Mikolajczyk, Malgorzata; Abe, Yuki; Barbato, Gaetano; Giannetti, Anthony M.; Krishnamoorthy, Ganeshram; Beusink, Bianca; Satpaev, Daulet; Tsang, Tiffany; Fang, Eric; Partridge, James; Brohawn, Stephen; Horn, James; Pritsch, Otto; Obal, Gonzalo; Nilapwar, Sanjay; Busby, Ben; Gutierrez-Sanchez, Gerardo; Gupta, Ruchira Das; Canepa, Sylvie; Witte, Krista; Nikolovska-Coleska, Zaneta; Cho, Yun Hee; D’Agata, Roberta; Schlick, Kristian; Calvert, Rosy; Munoz, Eva M.; Hernaiz, Maria Jose; Bravman, Tsafir; Dines, Monica; Yang, Min-Hsiang; Puskas, Agnes; Boni, Erica; Li, Jiejin; Wear, Martin; Grinberg, Asya; Baardsnes, Jason; Dolezal, Olan; Gainey, Melicia; Anderson, Henrik; Peng, Jinlin; Lewis, Mark; Spies, Peter; Trinh, Quyhn; Bibikov, Sergei; Raymond, Jill; Yousef, Mohammed; Chandrasekaran, Vidya; Feng, Yuguo; Emerick, Anne; Mundodo, Suparna; Guimaraes, Rejane; McGirr, Katy; Li, Yue-Ji; Hughes, Heather; Mantz, Hubert; Skrabana, Rostislav; Witmer, Mark; Ballard, Joshua; Martin, Loic; Skladal, Petr; Korza, George; Laird-Offringa, Ite; Lee, Charlene S.; Khadir, Abdelkrim; Podlaski, Frank; Neuner, Phillippe; Rothacker, Julie; Rafique, Ashique; Dankbar, Nico; Kainz, Peter; Gedig, Erk; Vuyisich, Momchilo; Boozer, Christina; Ly, Nguyen; Toews, Mark; Uren, Aykut; Kalyuzhniy, Oleksandr; Lewis, Kenneth; Chomey, Eugene; Pak, Brian J.; Myszka, David G.

    2013-01-01

    To explore the variability in biosensor studies, 150 participants from 20 countries were given the same protein samples and asked to determine kinetic rate constants for the interaction. We chose a protein system that was amenable to analysis using different biosensor platforms as well as by users of different expertise levels. The two proteins (a 50-kDa Fab and a 60-kDa glutathione S-transferase [GST] antigen) form a relatively high-affinity complex, so participants needed to optimize several experimental parameters, including ligand immobilization and regeneration conditions as well as analyte concentrations and injection/dissociation times. Although most participants collected binding responses that could be fit to yield kinetic parameters, the quality of a few data sets could have been improved by optimizing the assay design. Once these outliers were removed, the average reported affinity across the remaining panel of participants was 620 pM with a standard deviation of 980 pM. These results demonstrate that when this biosensor assay was designed and executed appropriately, the reported rate constants were consistent, and independent of which protein was immobilized and which biosensor was used. PMID:19133223

  17. Birth order and mortality: a population-based cohort study.

    PubMed

    Barclay, Kieron; Kolk, Martin

    2015-04-01

    This study uses Swedish population register data to investigate the relationship between birth order and mortality at ages 30 to 69 for Swedish cohorts born between 1938 and 1960, using a within-family comparison. The main analyses are conducted with discrete-time survival analysis using a within-family comparison, and the estimates are adjusted for age, mother's age at the time of birth, and cohort. Focusing on sibships ranging in size from two to six, we find that mortality risk in adulthood increases with later birth order. The results show that the relative effect of birth order is greater among women than among men. This pattern is consistent for all the major causes of death but is particularly pronounced for mortality attributable to cancers of the respiratory system and to external causes. Further analyses in which we adjust for adult socioeconomic status and adult educational attainment suggest that social pathways only mediate the relationship between birth order and mortality risk in adulthood to a limited degree.

  18. A flagellum based study of semiconductor nanofabrication through magnetotaxis.

    PubMed

    Macwan, Isaac; Zhao, Zihe; Sobh, Omar; Patra, Prabir

    2014-01-01

    Magnetospirillum magneticum (AMB-1), which belong to alpha-protobacterium are gram-negative, single-celled prokaryotic organisms consisting of a lash-like cellular appendage called flagella. These filamentous structures are made up of a protein called flagellin that in turn consist of four sub-domains, two inner domains (D0, D1) made up of alpha-helices and two outer domains (D2, D3) made up of beta sheets. It is wrapped in a helical fashion around the longitudinal filament with the outermost sub-domain (D3) exposed to the surrounding environment. This study focuses on the interaction of the D3 with semiconducting as well as metallic single-walled carbon nanotubes (m-SWNT) and in turn presents the interactive forces between the SWNT and D3 from the perspective of size and type of SWNT. It is found that the SWNT interacts the most with glycine and threonine residues of flagellin both electrostatically as well as through van der waals. Further, the viability of magnetotactic bacteria Magnetospirillum magneticum (AMB-1) in the presence of SWNT is experimentally investigated and it is found that magnetotaxis in AMB-1 is preserved without any toxic effects due to SWNT. It is proposed that AMB-1 can be used as an efficient carrier of carbon nanotubes through its flagellum for semiconductor nanofabrication tasks.

  19. Who Studies Women's Studies?

    ERIC Educational Resources Information Center

    Price, Marion; Owen, Mairead

    1998-01-01

    Studied a cohort (originally 44) of students who entered a British university to study women's studies in 1994. The strong emphases on the salience of the students' choice and the experiential importance of identity as a concept were striking. Theoretical difficulties in theorizing identity are explored. (SLD)

  20. Study on automatic testing network based on LXI

    NASA Astrophysics Data System (ADS)

    Hu, Qin; Xu, Xing

    2006-11-01

    LXI (LAN eXtensions for Instrumentation), which is an extension of the widely used Ethernet technology in the automatic testing field, is the next generation instrumental platform. LXI standard is based on the industry standard Ethernet technolog, using the standard PC interface as the primary communication bus between devices. It implements the IEEE802.3 standard and supports TCP/IP protocol. LXI takes the advantage of the ease of use of GPIB-based instruments, the high performance and compact size of VXI/PXI instruments, and the flexibility and high throughput of Ethernet all at the same time. The paper firstly introduces the specification of LXI standard. Then, an automatic testing network architecture which is based on LXI platform is proposed. The automatic testing network is composed of several sets of LXI-based instruments, which are connected via an Ethernet switch or router. The network is computer-centric, and all the LXI-based instruments in the network are configured and initialized in computer. The computer controls the data acquisition, and displays the data on the screen. The instruments are using Ethernet connection as I/O interface, and can be triggered over a wired trigger interface, over LAN or over IEEE 1588 Precision Time Protocol running over the LAN interface. A hybrid automatic testing network comprised of LXI compliant devices and legacy instruments including LAN instruments as well as GPIB, VXI and PXI products connected via internal or external adaptors is also discussed at the end of the paper.

  1. Study on hologram mosaic algorithm based on Harris corners

    NASA Astrophysics Data System (ADS)

    Yao, Jiabao; Tian, Qiuhong; Sun, Zhengrong; Huang, Liu; Wang, Limin

    2016-01-01

    To solve the problem of the small field of the view caused by CCD in the process of the hologram record, the hologram mosaic algorithm based on the Harris corners is proposed. The Harris corners in multi-scale are extracted and the mismatching points are removed. The final homography is calculated by using the improved RANSAC algorithm based on L-M algorithm. Finally, the stitched hologram with high quality can be obtained based on the weighted average fusion algorithm. It can overcome the influence to the hologram that the incident angles of the object beam are not consistent. Two experiments carried out with different reconstructed distance demonstrate that the proposed algorithm can realize the measurement of the big object by using the hologram method. Furthermore, it has high accuracy and strong robustness.

  2. A computational study of nodal-based tetrahedral element behavior.

    SciTech Connect

    Gullerud, Arne S.

    2010-09-01

    This report explores the behavior of nodal-based tetrahedral elements on six sample problems, and compares their solution to that of a corresponding hexahedral mesh. The problems demonstrate that while certain aspects of the solution field for the nodal-based tetrahedrons provide good quality results, the pressure field tends to be of poor quality. Results appear to be strongly affected by the connectivity of the tetrahedral elements. Simulations that rely on the pressure field, such as those which use material models that are dependent on the pressure (e.g. equation-of-state models), can generate erroneous results. Remeshing can also be strongly affected by these issues. The nodal-based test elements as they currently stand need to be used with caution to ensure that their numerical deficiencies do not adversely affect critical values of interest.

  3. Risk-based approach to petroleum hydrocarbon remediation. Research study

    SciTech Connect

    Miller, R.N.; Haas, P.; Faile, M.; Taffinder, S.

    1994-12-31

    The risk-based approach utilizes tools developed under the BTEX, Intrinsic Remediation (natural attenuation), Bioslurper, and Bioventing Initiatives of the Air Force Center for Environmental Excellence Technology Transfer Division (AFCEE/ERT) to construct a risk-based cost-effective approach to the cleanup of petroleum contaminated sites. The AFCEE Remediation Matrix (Enclosure 1) identifies natural attenuation as the first remediation alternative for soil and ground water contaminated with petroleum hydrocarbons. The intrinsic remediation (natural attenuation) alternative requires a scientifically defensible risk assessment based on contaminant sources, pathways, and receptors. For fuel contaminated sites, the first step is to determine contaminants of interest. For the ground water pathway (usually considered most important by regulators), this will normally be the most soluble, mobile, and toxic compounds, namely benzene, toluene, ethyl benzene, and o, m, p, xylene (BTEX).

  4. The Study on Collaborative Manufacturing Platform Based on Agent

    NASA Astrophysics Data System (ADS)

    Zhang, Xiao-yan; Qu, Zheng-geng

    To fulfill the trends of knowledge-intensive in collaborative manufacturing development, we have described multi agent architecture supporting knowledge-based platform of collaborative manufacturing development platform. In virtue of wrapper service and communication capacity agents provided, the proposed architecture facilitates organization and collaboration of multi-disciplinary individuals and tools. By effectively supporting the formal representation, capture, retrieval and reuse of manufacturing knowledge, the generalized knowledge repository based on ontology library enable engineers to meaningfully exchange information and pass knowledge across boundaries. Intelligent agent technology increases traditional KBE systems efficiency and interoperability and provides comprehensive design environments for engineers.

  5. A Method for Industrial Base Analysis: An Aerospace Case Study

    DTIC Science & Technology

    1993-01-01

    industrial base to build advanced weapon systems in the quantities required and at a reasonable price. A particular concern is the health of the subcontractor industrial base , which provides critical parts and technologies to prime contractors and is less visible than major prime contractors. This report presents a method to assess the impact of DoD budget cuts on both prime contractors and their first-tier subcontractors. The method considers supplier- contractor relationships, by weapon system, and builds a time profile of...sector and/or on the

  6. Gene-based segregation method for identifying rare variants in family-based sequencing studies.

    PubMed

    Qiao, Dandi; Lange, Christoph; Laird, Nan M; Won, Sungho; Hersh, Craig P; Morrow, Jarrett; Hobbs, Brian D; Lutz, Sharon M; Ruczinski, Ingo; Beaty, Terri H; Silverman, Edwin K; Cho, Michael H

    2017-02-13

    Whole-exome sequencing using family data has identified rare coding variants in Mendelian diseases or complex diseases with Mendelian subtypes, using filters based on variant novelty, functionality, and segregation with the phenotype within families. However, formal statistical approaches are limited. We propose a gene-based segregation test (GESE) that quantifies the uncertainty of the filtering approach. It is constructed using the probability of segregation events under the null hypothesis of Mendelian transmission. This test takes into account different degrees of relatedness in families, the number of functional rare variants in the gene, and their minor allele frequencies in the corresponding population. In addition, a weighted version of this test allows incorporating additional subject phenotypes to improve statistical power. We show via simulations that the GESE and weighted GESE tests maintain appropriate type I error rate, and have greater power than several commonly used region-based methods. We apply our method to whole-exome sequencing data from 49 extended pedigrees with severe, early-onset chronic obstructive pulmonary disease (COPD) in the Boston Early-Onset COPD study (BEOCOPD) and identify several promising candidate genes. Our proposed methods show great potential for identifying rare coding variants of large effect and high penetrance for family-based sequencing data. The proposed tests are implemented in an R package that is available on CRAN (https://cran.r-project.org/web/packages/GESE/).

  7. Insolation Weathering: An Instrumentation and Field Based Study (Invited)

    NASA Astrophysics Data System (ADS)

    Eppes, M. C.; Warren, K.; Swami, S.; Folz-Donahue, K.; Evans, S.; Cavendar, J.; Smith, I.; Layzell, A.

    2010-12-01

    Processes of mechanical weathering related to diurnal insolation are largely unexplored. Recent studies (McFadden et al., 2005, Eppes et al., 2010) demonstrated that rocks in a range of environments exhibit preferentially orientated (~N-S) cracks that are hypothesized to form as rocks are heated and cooled during the sun’s daily transit across the sky. In this study, we attempt to better understand the association between rock fracture and directional insolation. In Charlotte, NC we instrumented a ~30 cm diameter granite boulder sitting in full sun exposure with 8 thermocouples, 8 strain rosettes, 6 acoustic emission sensors and a moisture sensor, in order to spatially and temporally correlate rock cracking with rock surface conditions. Temperature and strain are recorded every minute along with a suite of meteorological data, and acoustic emissions are continuously monitored. As part of an NSF REU, in the Providence Mountains of the Mojave Desert of Southern California, we examined every crack greater than 2 cm in length on 1027 desert pavement rocks of varying types and on surfaces of varying age (~1 ka to ~150 ka) in order to examine crack characteristics as a function of rock shape, rock type and rock exposure age. Analysis of preliminary instrumentation data indicates that rock cracking as monitored by AE devices occurs in discrete intervals of events that initially appear to be related to rapid changes in temperature and/or temperature gradients on the rock surface. Using 3-D location software, we are also able to locate the foci of events within the rock to a reasonable degree of certainty. Our data will allow us to begin to quantify the stress and temperature conditions under which cracking occurs. Preliminary analysis of our field data indicates that cracks exhibit preferred strike orientations (~NE) and dip directions (~ESE). These data support the idea that cracking occurs in association with the extreme temperature gradients that arise as rocks are

  8. Reasoning Based Quality Assurance of Medical Ontologies: A Case Study

    PubMed Central

    Horridge, Matthew; Parsia, Bijan; Noy, Natalya F.; Musenm, Mark A.

    2014-01-01

    The World Health Organisation is using OWL as a key technology to develop ICD-11 – the next version of the well-known International Classification of Diseases. Besides providing better opportunities for data integration and linkages to other well-known ontologies such as SNOMED-CT, one of the main promises of using OWL is that it will enable various forms of automated error checking. In this paper we investigate how automated OWL reasoning, along with a Justification Finding Service can be used as a Quality Assurance technique for the development of large and complex ontologies such as ICD-11. Using the International Classification of Traditional Medicine (ICTM) – Chapter 24 of ICD-11 – as a case study, and an expert panel of knowledge engineers, we reveal the kinds of problems that can occur, how they can be detected, and how they can be fixed. Specifically, we found that a logically inconsistent version of the ICTM ontology could be repaired using justifications (minimal entailing subsets of an ontology). Although over 600 justifications for the inconsistency were initially computed, we found that there were three main manageable patterns or categories of justifications involving TBox and ABox axioms. These categories represented meaningful domain errors to an expert panel of ICTM project knowledge engineers, who were able to use them to successfully determine the axioms that needed to be revised in order to fix the problem. All members of the expert panel agreed that the approach was useful for debugging and ensuring the quality of ICTM. PMID:25954373

  9. FTIR studies of PVC/PMMA blend based polymer electrolytes

    NASA Astrophysics Data System (ADS)

    Ramesh, S.; Leen, Koay Hang; Kumutha, K.; Arof, A. K.

    2007-04-01

    The polymer electrolytes composing of the blend of polyvinyl chloride-polymethyl methacrylate (PVC/PMMA) with lithium triflate (LiCF 3SO 3) as salt, ethylene carbonate (EC) and dibutyl phthalate (DBP) as plasticizers and silica (SiO 2) as the composite filler were prepared. FTIR studies confirm the complexation between PVC/PMMA blends. The C sbnd Cl stretching mode at 834 cm -1 for pure PVC is shifted to 847 cm -1 in PVC-PMMA-LiCF 3SO 3 system. This suggests that there is interaction between Cl in PVC with Li + ion from LiCF 3SO 3. The band due to sbnd OCH 3 at 1150 cm -1 for PVC-PMMA blend is shifted to 1168 cm -1 in PVC-PMMA-LiCF 3SO 3 system. This shift is expected to be due to the interaction between Li + ion and the oxygen atom in PMMA. The symmetric vibration band and the asymmetric vibration band of LiCF 3SO 3 at 1033 and 1256 cm -1 shifted to 1075 and 1286 cm -1 in the DBP-EC plasticized PVC-PMMA-LiCF 3SO 3 complexes. The interaction between Li + ions and SiO 2 will lead to an increase in the number of free plasticizers (which does not interact with Li + ions). When the silica content increases from 2% to 5%, the intensity of the peak at 896 cm -1 (due to the ring breathing vibration of free EC) increases in PVC-PMMA-LiCF 3SO 3-DBP-EC system.

  10. Smoking during pregnancy: A population-based study.

    PubMed

    Oskarsdottir, Gudrun Nina; Sigurdsson, Hedinn; Gudmundsson, Kristjan G

    2017-02-01

    Tobacco is a major cause of disease and mortality in modern times. The risk of smoking in pregnancy is a serious threat to the development and future health of an unborn child. The aim of this study was to explore the epidemiological factors associated with smoking during pregnancy in a primary healthcare setting. All 856 maternity records at the Glaesibaer Health Care Centre in Reykjavik during 2006-2013 were reviewed and information on smoking habits investigated. The records showed that in 108 (12.2%) pregnancies, women smoked at first visit and 63 stopped smoking in early pregnancy, leaving 45 (5.3%) mothers smoking throughout the whole gestational period. The mean age of the smoking women was 27.8 years and for the non-smokers 29.7 years. Low social status (odds ratio (OR) = 2.66; 95% confidence interval (CI): 1.19-5.96), previous mental health diagnosis (OR = 2.7; 95% CI: 1.3-5.6), and unstable relationship with a partner (OR = 3.78; 95% CI: 2.1-7.0) were associated with smoking. Smoking fewer cigarettes was associated with a 0.04-unit lower risk of smoking during pregnancy (OR = 0.04: 95% CI: 0.02-0.08). Our results indicated that the women who smoked during pregnancy were often heavy smokers and living without a partner. They were younger, had worse mental health, and a lower social status than those pregnant women who did not smoke. Bearing in mind the consequence of smoking in pregnancy, this subgroup should get increased assistance to quit smoking before and during early pregnancy, as well as appropriate medical and social support.

  11. Software-based evaluation of human attractiveness: a pilot study.

    PubMed

    Patzelt, Sebastian B M; Schaible, Leonie K; Stampf, Susanne; Kohal, Ralf J

    2014-11-01

    The difficulty of evaluating esthetics in an unbiased way may be overcome by using automated software applications. The purpose of this study was to assess the use of a smartphone application as an objective tool for evaluating attractiveness and to evaluate its potential in dentistry. Ten white participants (mean age ±SD, 42.1 ±22.6 years) were randomly chosen, and frontal facial pictures of each participant were made. The smartphone application PhotoGenic was used to evaluate the attractiveness of the participants. For comparison, 100 randomly (age>16 years, social environment of the research team) selected raters were asked to evaluate the same participants. The influence of participants' facial expression, age, and sex as well as the raters' age, sex, and occupation was investigated. Statistical analyses (linear mixed models with random intercepts; least square means, 95% confidence interval; P<.05) were implemented. PhotoGenic produced a mean ±SD attractiveness score of 6.4 ±1.2 and the rater group of 4.9 ±1.8 (P<.001; score range, 0-10). Female raters tended to slightly higher attractiveness scores. The participants' sex, facial expression, and age seemed to not be of high relevance; however, the raters' sex and occupation had an impact on the evaluation. PhotoGenic rated the participants' attractiveness with higher scores (more attractive) than did the human raters. Currently, PhotoGenic is not used as an objective evaluation tool for treatment outcomes for dental treatments because the visibility of the teeth (smiling facial expression) has no influence on the evaluation. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  12. Cheminformatics-Based Anticoagulant Study of Traditionally Used Medicinal Plants

    PubMed

    Alikhani Pour, Mahdi; Sardari, Soroush; Eslamifar, Ali; Azhar, Abid; Rezvani, Mohammad; Nazari, Milad

    2017-04-29

    Medicinal plants, as a complementary medicine, have been used to treat various diseases since ancient times. These plants have numerous beneficial applications and are the source of certain conventional drugs. In diseases such as stroke and ischemia, which are caused by several factors, abnormal coagulation is an important causative factor. Accordingly, novel and effective therapies such as herbal remedies should be practiced to prevent such lethal diseases. Using the available databases such as Google Scholar and PubMed, the previously reported anticoagulant compounds and plants possessing anticoagulant activity were identified and collected in two separate lists. Next, the fast and cost-effective cheminformatics methods incorporated in PubChem were applied to detect some compounds similar to reported anticoagulants. Subsequently, 15 native medical plants of Iran containing the potential anticoagulants were selected. The selected plants were purchased and chopped, and the potential compounds were extracted by ethanol. Then three concentrations of extracts (1, 10, and 100 µg per ml) were made. Finally, anticoagulant effect of the selected plants was evaluated by in vitro prothrombin time and activated partial thromboplastin time coagulation tests. Among the 15 selected medicinal plants, three plants, including Terminalia bellirica (P=0.0019), Astragalus arbusculinus (P=0.0021), and Origanum vulgare (P=0.0014) showed a more promising anticoagulant effect in comparison to the control. The anticoagulant activity was identified for the first time in these three plants. Further in vivo study and mechanism of action assay are required to be performed on these three plants, which could be suitable candidates for use as natural anticoagulant medicines.

  13. Permanent sequelae in sports injuries: a population based study

    PubMed Central

    Marchi, A.; Di, B; Messi, G.; Gazzola, G.

    1999-01-01

    AIM—To identify permanent sequelae after sports injuries in children and adolescents.
METHODS—In 1985, a prospective register was drawn up of all sports related injuries reported that year by the residents of Trieste, Italy aged 6-15 years. Moderate to severe injuries (scoring ⩾ 2 on the abbreviated injury scale (AIS)) were the object of a longitudinal clinical study. In 1988, 30.9% of the 220 subjects enrolled had sequelae. A further follow up was undertaken in 1997.
RESULTS—The follow up in 1997 involved 54 subjects (26 girls; average age 24.5 years). Subjective and objective sequelae, by now considered to be permanent, were found in 61.1%, corresponding to 15% of the AIS ⩾ 2 injuries recorded in 1985. The prevalence of sequelae was similar in the two sexes, in relation to the child's age at time of injury, and in the different sports practised. It was higher in relation to the severity of the lesion (89% of AIS 3injuries examined, 56% of AIS 2 injuries) and to the type of lesion and its location. With regard to AIS ⩾ 2 injuries, permanent sequelae were found in 50% of ankle fractures, 43% of elbow fractures, 33% of leg/foot fractures, 25% of knee sprains, and 23% of ankle sprains.
CONCLUSIONS—The frequency of sequelae in sports injuries in children and adolescents is high. The risk appears to be connected to certain anatomical and functional age characteristics. Prevention strategies should include specific assessment of physical fitness and adequate follow up after the accident, particularly rehabilitation.

 PMID:10490437

  14. Status Study of Competency Based Teacher Education Programs in Science.

    ERIC Educational Resources Information Center

    McCurdy, Donald W.

    The results of a survey of 53 members of the Association for the Education of Teachers in Science and of 76 institutions having some form of competency based teacher education (CBTE) program are tabulated in this document. The report is divided into two sections, one pertaining to CBTE programs in general and the other relating specifically to…

  15. Case Study of a Computer Based Examination System

    ERIC Educational Resources Information Center

    Fluck, Andrew; Pullen, Darren; Harper, Colleen

    2009-01-01

    Electronic supported assessment or e-Assessment is a field of growing importance, but it has yet to make a significant impact in the Australian higher education sector (Byrnes & Ellis, 2006). Current computer based assessment models focus on the assessment of knowledge rather than deeper understandings, using multiple choice type questions,…

  16. Implementing Outcomes Based Accountability in Children's Services. Case Studies

    ERIC Educational Resources Information Center

    Bergeron, Caroline; Chamberlain, Tamsin; George, Nalia; Golden, Sarah; Mundy, Ellie; Southcott, Clare; Walker, Fiona

    2010-01-01

    Outcomes Based Accountability (OBA) is an approach that Children's Trusts and Children's Services can use to assist with planning services and assessing their performance. The OBA approach focuses on outcomes that are desired and monitoring and evidencing progress towards those desired outcomes. OBA makes a distinction between two types of…

  17. Beyond Tier-Based Bigrams: An Artificial Grammar Learning Study

    ERIC Educational Resources Information Center

    Koo, Hahn; Oh, Young-il

    2013-01-01

    Some of recently proposed phonotactic learners are tier-based bigram learners that restrict their hypothesis space to patterns between two segments that are adjacent at the tier level. This assumption is understandable considering that typologically frequent nonadjacent sound patterns are predominantly those that hold between two tier-adjacent…

  18. Home-Based Crisis Therapy: A Comparative Outcome Study.

    ERIC Educational Resources Information Center

    Rowland, Charity; And Others

    Substitute care for a child at risk has been been associated with psychological distress in the child and his family and a drain on public finances. To investigate the cost effectiveness and ultimate influence on family intactness of home-based family crisis intervention, 77 low income, inner city families with an adolescent child at risk of…

  19. Case Study of a Computer Based Examination System

    ERIC Educational Resources Information Center

    Fluck, Andrew; Pullen, Darren; Harper, Colleen

    2009-01-01

    Electronic supported assessment or e-Assessment is a field of growing importance, but it has yet to make a significant impact in the Australian higher education sector (Byrnes & Ellis, 2006). Current computer based assessment models focus on the assessment of knowledge rather than deeper understandings, using multiple choice type questions,…

  20. [Study for phagaquosonogram acquisition module based on DSP].

    PubMed

    Lu, Qiang; Guo, Yong-Xin; Zhang, Guang-Yu; Cui, Dong; Wang, Shi-Gang; Jiao, Qing

    2009-07-01

    In this paper, a phagaquosonogram acquisition, a module with TMS320C6713 as a core, and USB as communicating pattern is introduced based on VC++6.0. The structure of the module, hardware configuration, software design and the experiment of the real phagaquosonogram signal collection are presented. It is shown that the module can extract human phagaquosonogram signal reliably and availably.