Investigation of alternate power source for Space Shuttle Orbiter hydraulic system

NASA Technical Reports Server (NTRS)

Simon, William E.; Young, Fred M.

1993-01-01

This investigation consists of a short-term feasibility study to determine whether or not an alternate electrical power source would trade favorably from a performance, reliability, safety, operation, and weight standpoint in replacing the current auxiliary power unit subsystems with its attendant components (water spray boiler, hydrazine fuel and tanks, feed and vent lines, controls, etc.), operating under current flight rules. Results of this feasibility study are used to develop recommendations for the next step (e.g., to determine if such an alternate electrical power source would show an advantage given that the current operational flight mode of the system could be modified in such a way as not to constrain the operational capability and safety of the vehicle). However, this next step is not within the scope of this investigation. This study does not include a cost analysis, nor does it include investigation of the integration aspects involved in such a trade, except in a qualitative sense for the determination of concept feasibility.

The effect of applied control strategy on the current-voltage correlation of a solid oxide fuel cell stack during dynamic operation

NASA Astrophysics Data System (ADS)

Szmyd, Janusz S.; Komatsu, Yosuke; Brus, Grzegorz; Ghigliazza, Francesco; Kimijima, Shinji; Ściążko, Anna

2014-09-01

This paper discusses the transient characteristics of the planar type SOFC cell stack, of which the standard output is 300 W. The transient response of the voltage to the manipulation of an electric current was investigated. The effects of the response and of the operating condition determined by the operating temperature of the stack were studied by mapping a current-voltage (I-V) correlation. The current-based fuel control (CBFC) was adopted for keeping the fuel utilization factor at constant while the value of the electric current was ramped at the constant rate. The present experimental study shows that the transient characteristics of the cell voltage are determined by primarily the operating temperature caused by the manipulation of the current. Particularly, the slope of the I-V curve and the overshoot found on the voltage was remarkably influenced by the operating temperature. The different values of the fuel utilization factor influence the height of the settled voltages. The CBFC has significance in determining the slope of the I-V characteristic, but the different values ofthe fuel utilization factor does not affect the slope as the operating temperature does. The CBFC essentially does not alter the amplitude of the overshoot on the voltage response, since this is dominated by the operating temperature and its change is caused by manipulating the current.

MgB2-based superconductors for fault current limiters

NASA Astrophysics Data System (ADS)

Sokolovsky, V.; Prikhna, T.; Meerovich, V.; Eisterer, M.; Goldacker, W.; Kozyrev, A.; Weber, H. W.; Shapovalov, A.; Sverdun, V.; Moshchil, V.

2017-02-01

A promising solution of the fault current problem in power systems is the application of fast-operating nonlinear superconducting fault current limiters (SFCLs) with the capability of rapidly increasing their impedance, and thus limiting high fault currents. We report the results of experiments with models of inductive (transformer type) SFCLs based on the ring-shaped bulk MgB2 prepared under high quasihydrostatic pressure (2 GPa) and by hot pressing technique (30 MPa). It was shown that the SFCLs meet the main requirements to fault current limiters: they possess low impedance in the nominal regime of the protected circuit and can fast increase their impedance limiting both the transient and the steady-state fault currents. The study of quenching currents of MgB2 rings (SFCL activation current) and AC losses in the rings shows that the quenching current density and critical current density determined from AC losses can be 10-20 times less than the critical current determined from the magnetization experiments.

Wave-induced drift of large floating sheets

NASA Astrophysics Data System (ADS)

Christensen, K. H.; Weber, J. E.

In this article we study the wave-induced drift of large, flexible shallow floating objects, referred to as sheets. When surface waves propagate through a sheet, they provide a mean stress on the sheet, resulting in a mean drift. In response, the sheet generates an Ekman current. The drift velocity of the sheet is determined by (i) the wave-induced stress, (ii) the viscous stress due to the Ekman current, and (iii) the Coriolis force. The sheet velocity and the current beneath the sheet are determined for constant and depth-varying eddy viscosities.

Industry Training: The Factors that Affect Demand. Discussion Paper.

ERIC Educational Resources Information Center

Smith, A.; Roberts, P.; Noble, C.; Hayton, G.; Thorne, E.

A study was conducted in Australia, to determine the factors that affect demand for job training. The study consisted of 30 detailed industry case studies, an industry analysis, and a literature review. Each case study examined current training practices, training decision making in the business, and the determinants of training for the…

Digital Simulation Games for Social Studies Classrooms

ERIC Educational Resources Information Center

Devlin-Scherer, Roberta; Sardone, Nancy B.

2010-01-01

Data from ten teacher candidates studying teaching methods were analyzed to determine perceptions toward digital simulation games in the area of social studies. This research can be used as a conceptual model of how current teacher candidates react to new methods of instruction and determine how education programs might change existing curricula…

Determination of nitrogen in coal macerals using electron microprobe technique-experimental procedure

USGS Publications Warehouse

Mastalerz, Maria; Gurba, L.W.

2001-01-01

This paper discusses nitrogen determination with the Cameca SX50 electron microprobe using PCO as an analyzing crystal. A set of conditions using differing accelerating voltages, beam currents, beam sizes, and counting times were tested to determine parameters that would give the most reliable nitrogen determination. The results suggest that, for the instrumentation used, 10 kV, current 20 nA, and a counting time of 20 s provides the most reliable nitrogen determination, with a much lower detection limit than the typical concentration of this element in coal. The study demonstrates that the electron microprobe technique can be used to determine the nitrogen content of coal macerals successfully and accurately. ?? 2001 Elsevier Science B.V. All rights reserved.

Welfare of apes in captive environments: comments on, and by, a specific group of apes.

PubMed

Savage-Rumbaugh, Sue; Wamba, Kanzi; Wamba, Panbanisha; Wamba, Nyota

2007-01-01

Accurately determining the proper captive environment for apes requires adequately assessing the psychological similarities between apes and humans. Scientists currently believe apes lack mental complexity (Millikan, 2006), raising questions concerning the evolution of human culture from ape-like societies (Tomasello, 1999). A long-term cultural study with bonobos suggests less intellectual divergence from humans than currently postulated (Savage-Rumbaugh, 2005). Because humans view apes as mentally limited, some current captive environments may appear idyllic while offering only an illusion of appropriate care, derived from a simplistic view of what apes are, rather than what they might be. This perception of apes determines their handling, which determines their mental development, which perpetuates the prevailing perception. Only breaking this cycle will allow the current perception of apes to change. Their usual captive environment limits any demonstration of culture. However, the bonobo study reveals what ape culture can become, which should affect future welfare considerations for at least those species genetically close to humans (bonobos and chimpanzees). Development of a languaged bonobo culture allows these nonhuman animals to provide their own responses regarding adequate ape welfare.

Prevalence and determinants of cigarette smoking among adolescents in Blantyre City, Malawi.

PubMed

Muula, A S

2007-01-01

Tobacco smoking is a major risk factor for non-communicable diseases such as ischaemic heart disease, stroke, chronic obstructive airways disease and several cancers. There is little data about the prevalence and determinants of smoking among adolescents in southern Africa. This study aimed to determine the prevalence and determinants of cigarette smoking among adolescents in Blantyre City, Malawi. Cross-sectional data were obtained from school-going adolescents in Blantyre in 2001 using the Global Youth Tobacco Survey data collection instrument. Data were analysed to determine prevalence of current and ever cigarette smoking, and predictors of smoking. The prevalence of current smoking and ever smoking were 3.0% and 15.6%, respectively. Predictors of current tobacco smoking included male gender, having friends or parents who smoked, having been exposed to advertisements about tobacco brands on television and having seen a lot of advertisements in newspapers and magazines. School programmes that included being taught about smoking in class and a class discussion on the dangers of tobacco were not associated with reduced current smoking. Intervention programmes aiming to curb tobacco smoking among adolescents should focus on dealing also with parental smoking, peer influence and pay special attention toward male gender. School-based programmes to prevent smoking should be evaluated as some may have little impact in influencing current smoking status.

Load flows and faults considering dc current injections

NASA Technical Reports Server (NTRS)

Kusic, G. L.; Beach, R. F.

1991-01-01

The authors present novel methods for incorporating current injection sources into dc power flow computations and determining network fault currents when electronic devices limit fault currents. Combinations of current and voltage sources into a single network are considered in a general formulation. An example of relay coordination is presented. The present study is pertinent to the development of the Space Station Freedom electrical generation, transmission, and distribution system.

Depression, Suicidal Behaviour, and Mental Disorders in Older Aboriginal Australians

PubMed Central

Shen, Yu-Tang; Radford, Kylie; Daylight, Gail; Cumming, Robert; Broe, Tony G. A.; Draper, Brian

2018-01-01

Aboriginal Australians experience higher levels of psychological distress, which may develop from the long-term sequelae of social determinants and adversities in early and mid-life. There is little evidence available on the impact of these on the mental health of older Aboriginal Australians. This study enrolled 336 Aboriginal Australian participants over 60 years from 5 major urban and regional areas in NSW, utilizing a structured interview on social determinants, and life-time history of physical and mental conditions; current psychosocial determinants and mental health. Univariate and multivariate analyses were utilized to examine the link between these determinants and current depressive scores and suicidality. There was a high rate of life-time depression (33.3%), current late-life depression (18.1%), and suicidal ideation (11.1%). Risk factors strongly associated with late-life depression included sleep disturbances, a history of suicidal behaviour, suicidal ideation in late-life and living in a regional location. This study supports certain historical and psychosocial factors predicting later depression in old age, and highlights areas to target for prevention strategies. PMID:29510527

Depression, Suicidal Behaviour, and Mental Disorders in Older Aboriginal Australians.

PubMed

Shen, Yu-Tang; Radford, Kylie; Daylight, Gail; Cumming, Robert; Broe, Tony G A; Draper, Brian

2018-03-04

Aboriginal Australians experience higher levels of psychological distress, which may develop from the long-term sequelae of social determinants and adversities in early and mid-life. There is little evidence available on the impact of these on the mental health of older Aboriginal Australians. This study enrolled 336 Aboriginal Australian participants over 60 years from 5 major urban and regional areas in NSW, utilizing a structured interview on social determinants, and life-time history of physical and mental conditions; current psychosocial determinants and mental health. Univariate and multivariate analyses were utilized to examine the link between these determinants and current depressive scores and suicidality. There was a high rate of life-time depression (33.3%), current late-life depression (18.1%), and suicidal ideation (11.1%). Risk factors strongly associated with late-life depression included sleep disturbances, a history of suicidal behaviour, suicidal ideation in late-life and living in a regional location. This study supports certain historical and psychosocial factors predicting later depression in old age, and highlights areas to target for prevention strategies.

Determination of the Peltier Coefficient of Germanium in a Vertical Bridgeman-Stockbarger Furnace

NASA Technical Reports Server (NTRS)

Weigel, Michaela E. K.; Matthiesen, David H.

1997-01-01

The Peltier effect is the fundamental mechanism that makes interface demarcation through current pulsing possible. If a method for calculating the necessary current density for effective demarcation is to be developed, it will be necessary to know the value of the Peltier coefficient. This study determined experimentally the value of the Peltier coefficient for gallium-doped germanium by comparing the change in average growth rates between current-on and current-off periods. Current-on and current-off layer thickness measurements were made using differential interference contrast microscopy and atomic force microscopy. It was found that the Joule and Thomson effects could not be neglected. Peltier coefficients calculated from the experimental data with an analysis that accounts for Joule, Thomson, and Peltier effects yielded an average value for the Peltier coefficient of 0.076 +/- 0.015 V.

Interface potential sensing from adsorption of human serum albumin (HSA) on carbon nanotube (CNT) monitored by zero current potentiometry for HSA determination.

PubMed

Wang, Huan; Wu, Yi; Song, Jun-Feng

2015-10-15

In this work, the adsorption of human serum albumin (HSA) on the bare multiwall carbon nanotube (MWNT) was investigated by a new electrochemical method, termed as zero current potentiometry. For this, a MWNT strip was prepared by directly adhering MWNTs on the transparent adhesive tape surface. Moreover, when HSA adsorbed onto MWNT at the MWNT/solution interface, an interface potential Ψ yielded. The interface potential Ψ as the zero current potential Ezcp simply related to it was monitored by zero current potentiometry. The relationship between the zero current potential Ezcp, the HSA concentration and others was established in simple stoichiometric relation. Based on this, both the adsorption of HSA on MWNT and the HSA determination can be studied. For the HSA determination, the theoretic conclusion consisted with experimental results. The zero current potential Ezcp was proportional to the HSA concentration in the range of 2.8 × 10(-8) - 3.4 × 10(-7)M with the limit of detection 2 × 10(-8)M. The linear regression equation was Ezcp/V (vs, SCE) = (0.159 ± 0.01) + (0.358 ± 0.02) × 10(6)CHSA (µM). This determination was fast, high sensitive and good selective. Copyright © 2015 Elsevier B.V. All rights reserved.

Determination of the High School Students' Attitudes towards Their Teachers

ERIC Educational Resources Information Center

Gelisli, Yücel; Baidrahmanov, Dossym Kh.; Beisenbaeva, Lyazzat; Sultanbek, Malik

2017-01-01

In the current study, the aim is to determine the high school students' attitudes towards their teachers depending on some variables and the relationship between their attitudes and achievements. Thus, the study was designed according to relational survey model. The population of the study, which was specified based on the purposive sampling…

Mathematics Achievement: Traditional Instruction and Technology-Assisted Course Delivery Methods

ERIC Educational Resources Information Center

Vilardi, Robert

2013-01-01

The purpose of this study was to analyze technology-assisted course delivery methods to determine their overall effectiveness as it pertains to mathematics courses. This study analyzed both current and historical data in mathematics classes in the areas of achievement, retention, and grade distribution. The goal of this study was to determine if…

Current concepts in cleft care: A multicenter analysis.

PubMed

Thiele, Oliver C; Kreppel, Matthias; Dunsche, Anton; Eckardt, Andre M; Ehrenfeld, Michael; Fleiner, Bernd; Gaßling, Volker; Gehrke, Gerd; Gerressen, Marcus; Gosau, Martin; Gröbe, Alexander; Haßfeld, Stefan; Heiland, Max; Hoffmeister, Bodo; Hölzle, Frank; Klein, Cornelius; Krüger, Maximilian; Kübler, Alexander C; Kübler, Norbert R; Kuttenberger, Johannes J; Landes, Constantin; Lauer, Günter; Martini, Markus; Merholz, Erich T; Mischkowski, Robert A; Al-Nawas, Bilal; Nkenke, Emeka; Piesold, Jörn U; Pradel, Winnie; Rasse, Michael; Rachwalski, Martin; Reich, Rudolf H; Rothamel, Daniel; Rustemeyer, Jan; Scheer, Martin; Schliephake, Henning; Schmelzeisen, Rainer; Schramm, Alexander; Schupp, Wiebke; Spitzer, Wolfgang J; Stocker, Erwin; Stoll, Christian; Terheyden, Hendrik; Voigt, Alexander; Wagner, Wilfried; Weingart, Dieter; Werkmeister, Richard; Wiltfang, Jörg; Ziegler, Christoph M; Zöller, Joachim E

2018-04-01

The current surgical techniques used in cleft repair are well established, but different centers use different approaches. To determine the best treatment for patients, a multi-center comparative study is required. In this study, we surveyed all craniofacial departments registered with the German Society of Maxillofacial Surgery to determine which cleft repair techniques are currently in use. Our findings revealed much variation in cleft repair between different centers. Although most centers did use a two-stage approach, the operative techniques and timing of lip and palate closure were different in every center. This shows that a retrospective comparative analysis of patient outcome between the participating centers is not possible and illustrates the need for prospective comparative studies to establish the optimal technique for reconstructive cleft surgery. Copyright © 2018 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Reading Comprehension to 1970: Its Theoretical and Empirical Bases, and Its Implementation in Secondary Professional Textbooks, Instructional Materials, and Tests.

ERIC Educational Resources Information Center

Harker, William John

This study was designed: (1) to determine current concepts of reading comprehension deriving from experimental investigations and theoretical statements, and (2) to establish whether these concepts are represented consistently in current secondary professional reading textbooks, instructional materials, and published tests. Current knowledge of…

An Exploration of Preferred Advising Styles at Baptist Affiliated Institutions of Higher Education

ERIC Educational Resources Information Center

Wyatt, Eric L.

2016-01-01

The purpose of the current study was to determine if there was congruence between college students' perceptions of their current academic advisor's advising style and their preferred advisor's academic advising style; examine if the relationship between current and preferred advisor's academic advising styles predicted a student's level of…

Theoretical and Experimental Study of the Primary Current Distribution in Parallel-Plate Electrochemical Reactors

ERIC Educational Resources Information Center

Vazquez Aranda, Armando I.; Henquin, Eduardo R.; Torres, Israel Rodriguez; Bisang, Jose M.

2012-01-01

A laboratory experiment is described to determine the primary current distribution in parallel-plate electrochemical reactors. The electrolyte is simulated by conductive paper and the electrodes are segmented to measure the current distribution. Experiments are reported with the electrolyte confined to the interelectrode gap, where the current…

Determination of linear defect depths from eddy currents disturbances

NASA Astrophysics Data System (ADS)

Ramos, Helena Geirinhas; Rocha, Tiago; Pasadas, Dário; Ribeiro, Artur Lopes

2014-02-01

One of the still open problems in the inspection research concerns the determination of the maximum depth to which a surface defect goes. Eddy current testing being one of the most sensitive well established inspection methods, able to detect and characterize different type of defects in conductive materials, is an adequate technique to solve this problem. This paper reports a study concerning the disturbances in the magnetic field and in the lines of current due to a machined linear defect having different depths in order to extract relevant information that allows the determination of the defect characteristics. The image of the eddy currents (EC) is paramount to understand the physical phenomena involved. The EC images for this study are generated using a commercial finite element model (FLUX). The excitation used produces a uniform magnetic field on the plate under test in the absence of defects and the disturbances due to the defects are compared with those obtained from experimental measurements. In order to increase the limited penetration depth of the method giant magnetoresistors (GMR) are used to lower the working frequency. The geometry of the excitation planar coil produces a uniform magnetic field on an area of around the GMR sensor, inducing a uniform eddy current distribution on the plate. In the presence of defects in the material surface, the lines of currents inside the material are deviated from their uniform direction and the magnetic field produced by these currents is sensed by the GMR sensor. Besides the theoretical study of the electromagnetic system, the paper describes the experiments that have been carried out to support the theory and conclusions are drawn for cracks having different depths.

Carbon Nanotubes Exposure Risk Assessment: From Toxicology to Epidemiologic Studies (Overview of the Current Problem)

PubMed Central

Fatkhutdinova, L. M.; Khaliullin, T. O.; Shvedova, A. A.

2015-01-01

Nanoscale size and fiber like structure of carbon nanotubes (CNTs) may determine high reactivity and penetration, as well as the pathogenicity of asbestos and other mineral fibers. Despite many in vitro and in vivo studies, the absence of full-scale data on CNT effects on human health clearly point out the necessity for epidemiological studies. Currently, several projects are initiated worldwide on studying health risks associated with the inhalation of industrial CNTs, including NIOSH-promoted research (United States), the European CANTES study, and the Russian CNT-ERA project. Studies comprising several successive steps, such as CNT exposure assessment in occupational settings, toxicological evaluation, and epidemiological observations, are critical for determining material safety and use criteria. PMID:26457172

A Comparative Study Concerning Administrative Aspects of Elementary Off-Campus Student Teaching Programs: Current Practices and Proposed Patterns.

ERIC Educational Resources Information Center

Armstrong, Robert J.

A study was made to determine the current status of selected administrative areas of student teaching programs in Massachusetts and cooperative student teaching programs throughout the nation, the desirability of establishing cooperative programs in Massachusetts, and the organization and impelementation of these programs. Specific administrative…

The Current State of Sustainability in Bioscience Laboratories: A Statistical Examination of a UK Tertiary Institute

ERIC Educational Resources Information Center

Wright, Hazel A.; Ironside, Joseph E.; Gwynn-Jones, Dylan

2008-01-01

Purpose: This study aims to identify the current barriers to sustainability in the bioscience laboratory setting and to determine which mechanisms are likely to increase sustainable behaviours in this specialised environment. Design/methodology/approach: The study gathers qualitative data from a sample of laboratory researchers presently…

Propulsion Study for Small Transport Aircraft Technology (STAT)

NASA Technical Reports Server (NTRS)

Gill, J. C.; Earle, R. V.; Staton, D. V.; Stolp, P. C.; Huelster, D. S.; Zolezzi, B. A.

1980-01-01

Propulsion requirements were determined for 0.5 and 0.7 Mach aircraft. Sensitivity studies were conducted on both these aircraft to determine parametrically the influence of propulsion characteristics on aircraft size and direct operating cost (DOC). Candidate technology elements and design features were identified and parametric studies conducted to select the STAT advanced engine cycle. Trade off studies were conducted to determine those advanced technologies and design features that would offer a reduction in DOC for operation of the STAT engines. These features were incorporated in the two STAT engines. A benefit assessment was conducted comparing the STAT engines to current technology engines of the same power and to 1985 derivatives of the current technology engines. Research and development programs were recommended as part of an overall technology development plan to ensure that full commercial development of the STAT engines could be initiated in 1988.

The Influence of the September 11, 2001 Attacks and Related Events Years Later on the Expectations and Experiences of Saudi Undergraduate Students Studying in the United States

ERIC Educational Resources Information Center

Ghaleb, Sarah Mohammad

2013-01-01

This study was designed to determine whether or not undergraduate Saudi Arabian students currently studying in the United States still expect and experience negativity more than a decade after the events related to September 11, 2001. The study target population is all undergraduate Saudi students currently studying through the Saudi Arabian…

Analyzing Task-Based User Study Data to Determine Colormap Efficiency

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

Ashton, Zoe Charon Maria; Wendelberger, Joanne Roth; Ticknor, Lawrence O.

2015-07-23

Domain scientists use colormaps to visualize their data. These are useful for identifying areas of interest including Eddy Identification and Characterizing Currents. New colormaps have been designed by visual artist Francesca Samsel. User studies have been implemented to determine whether or not these colormaps are an improvement.

The numeric calculation of eddy current distributions in transcranial magnetic stimulation.

PubMed

Tsuyama, Seichi; Hyodo, Akira; Sekino, Masaki; Hayami, Takehito; Ueno, Shoogo; Iramina, Keiji

2008-01-01

Transcranial magnetic stimulation (TMS) is a method to stimulate neurons in the brain. It is necessary to obtain eddy current distributions and determine parameters such as position, radius and bend-angle of the coil to stimulate target area exactly. In this study, we performed FEM-based numerical simulations of eddy current induced by TMS using three-dimentional human head model with inhomogeneous conductivity. We used double-cone coil and changed the coil radius and bend-angle of coil. The result of computer simulation showed that as coil radius increases, the eddy current became stronger everywhere. And coil with bend-angle of 22.5 degrees induced stronger eddy current than the coil with bendangle of 0 degrees. Meanwhile, when the bend-angle was 45 degrees, eddy current became weaker than these two cases. This simulation allowed us to determine appropriate parameter easier.

The Observational Determination of the Primordial Helium Abundance: a Y2K Status Report

NASA Astrophysics Data System (ADS)

Skillman, Evan D.

I review observational progress and assess the current state of the determination of the primordial helium abundance, Yp. At present there are two determinations with non-overlapping errors. My impression is that the errors have been under-estimated in both studies. I review recent work on errors assessment and give suggestions for decreasing systematic errors in future studies.

Development of the method of aggregation to determine the current storage area using computer vision and radiofrequency identification

NASA Astrophysics Data System (ADS)

Astafiev, A.; Orlov, A.; Privezencev, D.

2018-01-01

The article is devoted to the development of technology and software for the construction of positioning and control systems in industrial plants based on aggregation to determine the current storage area using computer vision and radiofrequency identification. It describes the developed of the project of hardware for industrial products positioning system in the territory of a plant on the basis of radio-frequency grid. It describes the development of the project of hardware for industrial products positioning system in the plant on the basis of computer vision methods. It describes the development of the method of aggregation to determine the current storage area using computer vision and radiofrequency identification. Experimental studies in laboratory and production conditions have been conducted and described in the article.

Determinants of quality of life in Brazilian patients with myasthenia gravis.

PubMed

Mourão, Aline Mansueto; Gomez, Rodrigo Santiago; Barbosa, Luiz Sergio Mageste; Freitas, Denise da Silva; Comini-Frota, Elizabeth Regina; Kummer, Arthur; Lemos, Stella Maris Aguiar; Teixeira, Antonio Lucio

2016-07-01

The aims of the current study were 1) to evaluate the reliability and validity of the Brazilian version of the 15-item Myasthenia Gravis Quality of Life Scale and 2) to investigate the quality of life of Brazilian patients with myasthenia gravis and its determinants. This cross-sectional study included 69 patients with myasthenia gravis who underwent neurological evaluation and completed questionnaires regarding quality of life (the 36-item Short Form of the Medical Outcomes Study and the 15-item Myasthenia Gravis Quality of Life Scale), anxiety and depressive symptoms. The Brazilian version of the 15-item Myasthenia Gravis Quality of Life Scale showed high internal consistency and good concurrent validity with the 36-item Short Form of the Medical Outcomes Study and its subscales. Determinants of quality of life in Brazilian patients with myasthenia gravis included the current status of myasthenia gravis as assessed by the Myasthenia Gravis Composite, the current prednisone dose and the levels of anxiety and depression. The Brazilian version of the 15-item Myasthenia Gravis Quality of Life Scale is a valid instrument. Symptom severity, prednisone dosage and anxiety and depression levels impact the quality of life of patients with myasthenia gravis.

Determinants of quality of life in Brazilian patients with myasthenia gravis

PubMed Central

Mourão, Aline Mansueto; Gomez, Rodrigo Santiago; Barbosa, Luiz Sergio Mageste; da Silva Freitas, Denise; Comini-Frota, Elizabeth Regina; Kummer, Arthur; Lemos, Stella Maris Aguiar; Teixeira, Antonio Lucio

2016-01-01

OBJECTIVES: The aims of the current study were 1) to evaluate the reliability and validity of the Brazilian version of the 15-item Myasthenia Gravis Quality of Life Scale and 2) to investigate the quality of life of Brazilian patients with myasthenia gravis and its determinants. METHODS: This cross-sectional study included 69 patients with myasthenia gravis who underwent neurological evaluation and completed questionnaires regarding quality of life (the 36-item Short Form of the Medical Outcomes Study and the 15-item Myasthenia Gravis Quality of Life Scale), anxiety and depressive symptoms. RESULTS: The Brazilian version of the 15-item Myasthenia Gravis Quality of Life Scale showed high internal consistency and good concurrent validity with the 36-item Short Form of the Medical Outcomes Study and its subscales. Determinants of quality of life in Brazilian patients with myasthenia gravis included the current status of myasthenia gravis as assessed by the Myasthenia Gravis Composite, the current prednisone dose and the levels of anxiety and depression. CONCLUSION: The Brazilian version of the 15-item Myasthenia Gravis Quality of Life Scale is a valid instrument. Symptom severity, prednisone dosage and anxiety and depression levels impact the quality of life of patients with myasthenia gravis. PMID:27464292

Psychosocial Determinants of Tobacco Use among School Going Adolescents in Delhi, India

PubMed Central

Kumar, Varun; Talwar, Richa; Roy, Neelam; Raut, Deepak; Singh, Saudan

2014-01-01

Background. Tobacco use is one of the major preventable causes of premature death and disease in the world. Many psychosocial factors were found to influence tobacco use. Therefore the present study was designed to determine the role of psychosocial factors associated with tobacco use among school going adolescents in Delhi, India. Methods. Cross-sectional study was conducted from February 2013 to September 2013 in four government schools in South district of Delhi, India. The questionnaire contains questions adapted from GYTS (Global Youth Tobacco Survey) to find the prevalence and pattern of tobacco use among adolescents. Data were analyzed using SPSS version 21. Results. The prevalence of ever and current tobacco use was found in 16.4% and 13.1%. Current smoking and current tobacco chewing were found in 10.2% and 9.4% students, respectively. The risk of current tobacco use was found to be higher among males (P value = 0.000) and in those who got higher pocket money (P value = 0.000). Psychosocial factors like lower general self-efficacy and maladjustments with peers, teachers, and schools were also found to be significant predictors of current tobacco use. Conclusion. The study has revealed higher prevalence of ever and current tobacco use among adolescent students in Delhi, India. PMID:25431738

The Effects of the Activities of Current Textbook and 5 E Model on the Attitude of the Students: Sample of "The Global Effects of Natural Resources Unit"

ERIC Educational Resources Information Center

Uzunoz, Abdulkadir

2011-01-01

This study aimed to determine the effects of the activities of current textbook and 5 E Model on the attitude of the students. This study is a research as an experimental model. For testing the effects of geography education supported by 5 E model and geography education based on activities of current textbook attitude of students, controlled…

Nondestructive examination of the Tropical Rainfall Measuring Mission (TRMM) reaction control subsystem (RCS) propellant tanks

NASA Technical Reports Server (NTRS)

Free, James M.

1993-01-01

This paper assesses the feasibility of using eddy current nondestructive examination to determine flaw sizes in completely assembled hydrazine propellant tanks. The study was performed by the NASA Goddard Space Flight Center for the Tropical Rainfall Measuring Mission (TRMM) project to help determine whether existing propellant tanks could meet the fracture analysis requirements of the current pressure vessel specification, MIL-STD-1522A and, therefore be used on the TRMM spacecraft. After evaluating several nondestructive test methods, eddy current testing was selected as the most promising method for determining flaw sizes on external and internal surfaces of completely assembled tanks. Tests were conducted to confirm the detection capability of the eddy current NDE, procedures were developed to inspect two candidate tanks, and the test support equipment was designed. The non-spherical tank eddy current NDE test program was terminated when the decision was made to procure new tanks for the TRMM propulsion subsystem. The information on the development phase of this test program is presented in this paper as a reference for future investigation on the subject.

Current Emergency Locator Transmitter (ELT) deficiencies and potential improvements utilizing TSO-C91a ELTs

NASA Technical Reports Server (NTRS)

Trudell, Bernard J.; Dreibelbis, Ryland R.

1990-01-01

An analysis was conducted of current ELT problems and potential improvements that could be made by employing the TSO-C91a ELTs to replace the current TSO-C91 ELTs. The scope of the study included the following: (1) validate the problems; (2) determine specific failure causes; (3) determine false alarm causes; (4) estimate improvements from TSO-C91a; (5) estimate benefits from replacement of the current ELTs; and (6) determine need and benefits for improved ELT inspection and maintenance. A detailed comparison between the two requirements documents (TSO-C91 and -91a) was made to assess improved performance of the ELT in each category of failure cause and each cause of false alarms. The comparison and analysis resulted in projecting a success of operation rate approximately 3 times the current rate and a reduction in false alarms to 0.25 of those generated by TSO-C91 ELTs. These improvements led to a projection of benefits of approximately 25 additional lives to be saved each year with TSO-C91a ELTs and an improved inspection and maintenance program.

Teachers' Opinions about Professional Development Schools=Ögretmenlerin Mesleki Gelisim Okullarina Iliskin Görüsleri

ERIC Educational Resources Information Center

Ulubey, Özgür; Yildirim, Kasim; Alpaslan, Muhammet Mustafa; Aykaç, Necdet

2017-01-01

The purpose of the current study is to determine teachers' opinions about professional development schools. In the current study; one of the mixed methods, the convergent design was employed. The sampling of the quantitative dimension of the study is comprised of 256 teachers working in 21 elementary and secondary schools in the city of Mugla. The…

Analysis of tidal currents in the North Sea from shipboard acoustic Doppler current profiler data

NASA Astrophysics Data System (ADS)

Vindenes, Håvard; Orvik, Kjell Arild; Søiland, Henrik; Wehde, Henning

2018-06-01

North Sea tidal currents are determined by applying harmonic analysis to ship-borne acoustic Doppler current profiler data recorded from 1999 to 2016, covering large areas of the northern North Sea. Direct current measurement data sets of this magnitude are rare in the otherwise well investigated North Sea, and thus it is a valuable asset in studying and expanding our understanding of its tidal currents and circulation in general. The harmonic analysis is applied to a least squares fit of the current observations at a set of knot points. Results from the harmonic analysis compare favorably to tidal parameters estimated from observations from moored instruments. The analysis shows that the tides are characterized by strong semi-diurnal component, with amplitudes of the principal Lunar constituent ranging from 1.6 cm/s in the Skagerrak to 67 cm/s in the Fair Isle Channel. Diurnal tides are found to be approximately one fifth the strength of the predominant semi-diurnal constituent. Output from a regional barotropic tide model compares well to tidal current determined from the harmonic analysis of the Acoustic Doppler Current Profiler data.

Environmental regulation of sex determination in oil palm: current knowledge and insights from other species.

PubMed

Adam, Hélène; Collin, Myriam; Richaud, Frédérique; Beulé, Thierry; Cros, David; Omoré, Alphonse; Nodichao, Leifi; Nouy, Bruno; Tregear, James W

2011-12-01

The African oil palm (Elaeis guineensis) is a monoecious species of the palm subfamily Arecoideae. It may be qualified as 'temporally dioecious' in that it produces functionally unisexual male and female inflorescences in an alternating cycle on the same plant, resulting in an allogamous mode of reproduction. The 'sex ratio' of an oil palm stand is influenced by both genetic and environmental factors. In particular, the enhancement of male inflorescence production in response to water stress has been well documented. This paper presents a review of our current understanding of the sex determination process in oil palm and discusses possible insights that can be gained from other species. Although some informative phenological studies have been carried out, nothing is as yet known about the genetic basis of sex determination in oil palm, nor the mechanisms by which this process is regulated. Nevertheless new genomics-based techniques, when combined with field studies and biochemical and molecular cytological-based approaches, should provide a new understanding of the complex processes governing oil palm sex determination in the foreseeable future. Current hypotheses and strategies for future research are discussed.

Stray Current Corrosion in Electrified Rail Systems - Final Report

DOT National Transportation Integrated Search

1995-05-01

The objectives of this study were (1)to assess the scope of stray-current corrosion on electrified rail systems based upon information in the literature and from interviews with selected transit system operators, and (2)to determine whether new or ad...

State of the Art of Current Practices for Transit Transfers.

DOT National Transportation Integrated Search

1981-07-01

The major objectives of the study are to: (1) describe and summarize the transfer policies currently in use on U.S. transit properties; (2) identify reasons why properties use or do not use particular transfer policies; (3) determine the consequences...

CURRENT PRACTICES IN QSAR DEVELOPMENT AND APPLICATIONS

EPA Science Inventory

Current Practices in QSAR Development and Applications

Although it is commonly assumed that the structure and properties of a single chemical determines its activity in a particular biological system, it is only through study of how biological activity varies with changes...

Determining Science Student Teachers' Cognitive Structure on the Concept of "Food Chain"

ERIC Educational Resources Information Center

Çinar, Derya

2015-01-01

The current study aims to determine science student teachers' cognitive structure on the concept of food chain. Qualitative research method was applied in this study. Fallacies detected in the pre-service teachers' conceptual structures are believed to result in students' developing misconceptions in their future classes and will adversely affect…

Sight-Singing Assessment: A Study of Current Beliefs and Practices of Georgia Middle and High School Choral Directors

ERIC Educational Resources Information Center

Goss, Douglass Anthony

2010-01-01

This study sought to ascertain the specific assessment strategies used by middle- and high-school choral directors in Georgia to evaluate sight-singing. Data was further gathered to determine which assessment practices choral directors considered to be the most effective. Although there had been previous studies that attempted to determine the…

Australians as International Students--Where They Go, What They Do and Why They Do It

ERIC Educational Resources Information Center

Nerlich, Steve

2013-01-01

Current published information on the Australian student mobility offshore is reviewed as part of a long-term project aiming to determine the current propensity of Australian higher education students to study overseas and the return on investment that they can expect to achieve. It was found that limited data are available on the current extent of…

Assessment of United States and Japanese Athletic Trainers' Satisfaction with Current Ascension Pathways and Interest in Future Transnational Certification

ERIC Educational Resources Information Center

Presuto, Dax A.

2013-01-01

Background: The purpose of this cross-system and cross-cultural study was to investigate the current athletic training systems in the US and Japan, to assess US and Japanese athletic trainers' satisfaction with current athletic training ascension pathways in their respective country and to determine their interest in future transnational…

A Comparison of Three Determinants of an Engagement Index for Use in a Simulated Flight Environment

NASA Technical Reports Server (NTRS)

Hitt, James M., II

1995-01-01

The following report details a project design that is to be completed by the end of the year. Determining how engaged a person is at a task is rather difficult. There are many different ways to assess engagement. One such method is to use psychophysical measures. The current study focuses on three determinants of an engagement index proposed by researchers at NASA-Langley (Pope, A. T., Bogart, E. H., and Bartolome, D. S., 1995). The index (20 Beta/(Alpha+Theta)) uses EEG power bands to determine a person's level of engagement while performs a compensatory tracking task. The tracking task switches between manual and automatic modes. Participants each experience both positive and negative feedback within each trial of the three trials. The tracking task is altered in terms of difficulty depending on the participants current engagement index. The rationale of this study is to determine the optimal level of engagement to gain peak performance. The three determinants are based on an absolute index which differs from the past research which uses a slope index.

Study of Ni-Mo electrodeposition in direct and pulse-reverse current

NASA Astrophysics Data System (ADS)

Stryuchkova, Yu M.; Rybin, N. B.; Suvorov, D. V.; Gololobov, G. P.; Tolstoguzov, A. B.; Tarabrin, D. Yu; Serpova, M. A.; Korotchenko, V. A.; Slivkin, E. V.

2017-05-01

Process of electrochemical deposition of the coating based on a binary nickel-molybdenum alloy onto a nickel substrate under pulse mode with current reverse within the range of current density change from 2 to 9 A/dm2 has been researched. Coating structure and its surface morphology have been studied. Method of X-ray energy dispersive spectroscopy has determined a percentage ratio of alloy components in the coating. Mode to obtain the densest and smoothest deposits has been identified under considered terms.

Space station contamination control study: Internal combustion, phase 1

NASA Technical Reports Server (NTRS)

Ruggeri, Robert T.

1987-01-01

Contamination inside Space Station modules was studied to determine the best methods of controlling contamination. The work was conducted in five tasks that identified existing contamination control requirements, analyzed contamination levels, developed outgassing specification for materials, wrote a contamination control plan, and evaluated current materials of offgassing tests used by NASA. It is concluded that current contamination control methods can be made to function on the Space Station for up to 1000 days, but that current methods are deficient for periods longer than about 1000 days.

Effects of Low-frequency Current Sacral Dermatome Stimulation on Idiopathic Slow Transit Constipation

PubMed Central

Kim, Jin-Seop; Yi, Seung-Ju

2014-01-01

[Purpose] This study aimed to determine whether low-frequency current therapy can be used to reduce the symptoms of idiopathic slow transit constipation (ISTC). [Subjects] Fifteen patients (ten male and five female) with idiopathic slow transit constipation were enrolled in the present study. [Results] Bowel movements per day, bowel movements per week, and constipation assessment scale scores significantly improved after low-frequency current simulation of S2-S3. [Conclusion] Our results show that stimulation with low-frequency current of the sacral dermatomes may offer therapeutic benefits for a subject of patients with ISTC. PMID:25013277

Effects of Low-frequency Current Sacral Dermatome Stimulation on Idiopathic Slow Transit Constipation.

PubMed

Kim, Jin-Seop; Yi, Seung-Ju

2014-06-01

[Purpose] This study aimed to determine whether low-frequency current therapy can be used to reduce the symptoms of idiopathic slow transit constipation (ISTC). [Subjects] Fifteen patients (ten male and five female) with idiopathic slow transit constipation were enrolled in the present study. [Results] Bowel movements per day, bowel movements per week, and constipation assessment scale scores significantly improved after low-frequency current simulation of S2-S3. [Conclusion] Our results show that stimulation with low-frequency current of the sacral dermatomes may offer therapeutic benefits for a subject of patients with ISTC.

Decision Support for Renewal of Wastewater Collection and Water Distribution Systems

EPA Science Inventory

The objective of this study was to identify the current decision support methodologies, models and approaches being used for determining how to rehabilitate or replace underground utilities; identify the critical gaps of these current models through comparison with case history d...

Exploring the ring current of carbon nanotubes by first-principles calculations.

PubMed

Ren, Pengju; Zheng, Anmin; Xiao, Jianping; Pan, Xiulian; Bao, Xinhe

2015-02-01

Ring current is a fundamental concept to understand the nuclear magnetic resonance (NMR) properties and aromaticity for conjugated systems, such as carbon nanotubes (CNTs). Employing the recently developed gauge including projector augmented wave (GIPAW) method, we studied the ring currents of CNTs systematically and visualized their distribution. The ring current patterns are determined by the semiconducting or metallic properties of CNTs. The discrepancy is mainly caused by the axial component of external magnetic fields, whereas the radial component induced ring currents are almost independent of the electronic structures of CNTs, where the intensities of the ring currents are linearly related to the diameters of the CNTs. Although the ring currents induced by the radial component are more intense than those by the axial component, only the latter determines the overall NMR responses and aromaticity of the CNTs as well. Furthermore, the semiconducting CNTs are more aromatic than their metallic counterparts due to the existence of delocalized ring currents on the semiconducting CNTs. These fundamental features are of vital importance for the development of CNT-based nanoelectronics and applications in magnetic fields.

Exploring the ring current of carbon nanotubes by first-principles calculations

PubMed Central

Ren, Pengju; Zheng, Anmin; Xiao, Jianping; Pan, Xiulian

2015-01-01

Ring current is a fundamental concept to understand the nuclear magnetic resonance (NMR) properties and aromaticity for conjugated systems, such as carbon nanotubes (CNTs). Employing the recently developed gauge including projector augmented wave (GIPAW) method, we studied the ring currents of CNTs systematically and visualized their distribution. The ring current patterns are determined by the semiconducting or metallic properties of CNTs. The discrepancy is mainly caused by the axial component of external magnetic fields, whereas the radial component induced ring currents are almost independent of the electronic structures of CNTs, where the intensities of the ring currents are linearly related to the diameters of the CNTs. Although the ring currents induced by the radial component are more intense than those by the axial component, only the latter determines the overall NMR responses and aromaticity of the CNTs as well. Furthermore, the semiconducting CNTs are more aromatic than their metallic counterparts due to the existence of delocalized ring currents on the semiconducting CNTs. These fundamental features are of vital importance for the development of CNT-based nanoelectronics and applications in magnetic fields. PMID:29560175

Determination of plasma pinch time and effective current radius of double planar wire array implosions from current measurements on a 1-MA linear transformer driver

NASA Astrophysics Data System (ADS)

Steiner, Adam M.; Yager-Elorriaga, David A.; Patel, Sonal G.; Jordan, Nicholas M.; Gilgenbach, Ronald M.; Safronova, Alla S.; Kantsyrev, Victor L.; Shlyaptseva, Veronica V.; Shrestha, Ishor; Schmidt-Petersen, Maximillian T.

2016-10-01

Implosions of planar wire arrays were performed on the Michigan Accelerator for Inductive Z-pinch Experiments, a linear transformer driver (LTD) at the University of Michigan. These experiments were characterized by lower than expected peak currents and significantly longer risetimes compared to studies performed on higher impedance machines. A circuit analysis showed that the load inductance has a significant impact on the current output due to the comparatively low impedance of the driver; the long risetimes were also attributed to high variability in LTD switch closing times. A circuit model accounting for these effects was employed to measure changes in load inductance as a function of time to determine plasma pinch timing and calculate a minimum effective current-carrying radius. These calculations showed good agreement with available shadowgraphy and x-ray diode measurements.

OXYGEN DISSOCIATION OF WHOLE BLOOD STUDIED POLAROGRAPHICALLY

PubMed Central

Markus, Gabor; Baumberger, J. Percy

1952-01-01

The polarographic current of whole blood is in excess of that given by plasma at the same oxygen tension. The magnitude of this difference depends on (a) the oxygen content of the sample and thus is determined by the red blood cell content and by the state of oxygen saturation of hemoglobin, and (b) on the rate of dissociation of oxyhemoglobin and therefore is influenced by changes in pH, pCO2, and temperature. The total current at 37°C. is proportional to the oxygen content of the sample and can be used to determine the latter. The theoretical basis of the studied phenomena is discussed in detail. PMID:13011281

Ocean transport and variability studies of the South Pacific, Southern, and Indian Oceans

NASA Technical Reports Server (NTRS)

Church, John A.; Cresswell, G. R.; Nilsson, C. S.; Mcdougall, T. J.; Coleman, R.; Rizos, C.; Penrose, J.; Hunter, J. R.; Lynch, M. J.

1991-01-01

The objectives of this study are to analyze ocean dynamics in the western South Pacific and the adjacent Southern Ocean and the eastern Indian Ocean. Specifically, our objectives for these three regions are, for the South Pacific Ocean: (1) To estimate the volume transport of the east Australian Current (EAC) along the Australian coast and in the Tasman Front, and to estimate the time variability (on seasonal and interannual time scales) of this transport. (2) To contribute to estimating the meridional heat and freshwater fluxes (and their variability) at about 30 deg S. Good estimates of the transport in the western boundary current are essential for accurate estimates of these fluxes. (3) To determine how the EAC transport (and its extension, the Tasman Front and the East Auckland Current) closes the subtropical gyre of the South Pacific and to better determine the structure at the confluence of this current and the Antarctic Circumpolar Current. (4) To examine the structure and time variability of the circulation in the western South Pacific and the adjacent Southern Ocean, particularly at the Tasman Front. For the Indian Ocean: (5) To study the seasonal interannual variations in the strength of the Leeuwin Current. (6) To monitor the Pacific-Indian Ocean throughflow and the South Equatorial and the South Java Currents between northwest Australia and Indonesia. (7) To study the processes that form the water of the permanent oceanic thermocline and, in particular, the way in which new thermocline water enters the permanent thermocline in late winter and early spring as the mixed layer restratifies. For the Southern Ocean: (8) To study the mesoscale and meridional structure of the Southern Ocean between 150 deg E and 170 deg E; in particular, to describe the Antarctic frontal system south of Tasmania and determine its interannual variability; to estimate the exchanges of heat, salt, and other properties between the Indian and Pacific Oceans; and to investigate the annual ventilation of the Antarctic Intermediate Water and Subantarctic Mode Water Masses.

NR2C in the thalamic reticular nucleus; effects of the NR2C knockout.

PubMed

Zhang, Yuchun; Buonanno, Andres; Vertes, Robert P; Hoover, Walter B; Lisman, John E

2012-01-01

NMDAR antagonists can evoke delta frequency bursting in the nucleus reticularis of the thalamus (nRT). The mechanism of this oscillation was determined; antagonist blocks an NR2C-like conductance that has low Mg block at resting potential and thus can contribute a resting inward current in response to ambient glutamate. Block of this current hyperpolarizes the cell, deinactivating T-type Ca channels and thus triggering delta frequency bursting. The basis for assuming a NR2C-like conductance was that (1) transcripts for NR2C are abundant in the thalamus and (2) the current-voltage curve of the synaptically evoked NMDAR current has the low rectification characteristic of NR2C. In the current study, we have sought to determine whether the channels that generate the NMDAR current are NR2C-like or are actually comprised of receptors containing NR2C. We studied the current-voltage curve of synaptically evoked NMDAR current in the nRT of NR2C knockout mice. In wild-type mice, the current was weakly voltage dependent, as previously observed in rats. This weak rectification was absent in NR2C KO mice. In contrast, NR2C KO had no effect on the strongly rectifying NMDAR current in pyramidal cells of the prefrontal cortex. These results demonstrate that the low rectification normally observed in the nRT is due to NR2C.

Interhemispheric currents in the ring current region as seen by the Cluster spacecraft

NASA Astrophysics Data System (ADS)

Tenfjord, P.; Ostgaard, N.; Haaland, S.; Laundal, K.; Reistad, J. P.

2013-12-01

The existence of interhemispheric currents has been predicted by several authors, but their extent in the ring current has to our knowledge never been studied systematically by using in-situ measurements. These currents have been suggested to be associated with observed asymmetries of the aurora. We perform a statistical study of current density and direction during ring current crossings using the Cluster spacecraft. We analyse the extent of the interhemispheric field aligned currents for a wide range of solar wind conditions. Direct estimations of equatorial current direction and density are achieved through the curlometer technique. The curlometer technique is based on Ampere's law and requires magnetic field measurements from all four spacecrafts. The use of this method requires careful study of factors that limit the accuracy, such as tetrahedron shape and configuration. This significantly limits our dataset, but is a necessity for accurate current calculations. Our goal is to statistically investigate the occurrence of interhemispheric currents, and determine if there are parameters or magnetospheric states on which the current magnitude and directions depend upon.

Investigation of electrodes under flow of a submicrosecond current pulse with linear density up to 3 MA/cm

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

Branitskii, A. V.; Grabovskii, E. V.; Dzhangobegov, V. V.

The states of current-carrying elements at the transmission of megaampere current into load are studied. It is determined that the expansion velocity of plasma generated at the outer surface of cylindrical tubes produced of stainless steel, at flowing through them of submicrosecond current pulses with linear density of 3 MA/cm is 5.5 km/s. The evolution of various modes of instability is analyzed.

Transient interaction model of electromagnetic field generated by lightning current pulses and human body

NASA Astrophysics Data System (ADS)

Iváncsy, T.; Kiss, I.; Szücs, L.; Tamus, Z. Á.

2015-10-01

The lightning current generates time-varying magnetic field near the down- conductor and the down-conductors are mounted on the wall of the buildings where residential places might be situated. It is well known that the rapidly changing magnetic fields can generate dangerous eddy currents in the human body.The higher duration and gradient of the magnetic field can cause potentially life threatening cardiac stimulation. The coupling mechanism between the electromagnetic field and the human body is based on a well-known physical phenomena (e.g. Faradays law of induction). However, the calculation of the induced current is very complicated because the shape of the organs is complex and the determination of the material properties of living tissues is difficult, as well. Our previous study revealed that the cardiac stimulation is independent of the rising time of the lightning current and only the peak of the current counts. In this study, the authors introduce an improved model of the interaction of electromagnetic fields of lighting current near down-conductor and human body. Our previous models are based on the quasi stationer field calculations, the new improved model is a transient model. This is because the magnetic field around the down-conductor and in the human body can be determined more precisely, therefore the dangerous currents in the body can be estimated.

Cross-Cultural Analyses of Determinants of Quality of Life and Mental Health: Results from the Eurohis Study

ERIC Educational Resources Information Center

Schmidt, Silke; Power, Mick

2006-01-01

Recent projects on international instrument development have produced a wide array of health indicators that may be used for cross-cultural field-testing, however more information on their cross-cultural performance in relation to health determinants is necessary. The current study approaches one step for international conceptual validation by…

Determining an Effective Intervention within a Brief Experimental Analysis for Reading: A Meta-Analytic Review

ERIC Educational Resources Information Center

Burns, Matthew K.; Wagner, Dana

2008-01-01

The current study applied meta-analytic procedures to brief experimental analysis research of reading fluency interventions to better inform practice and suggest areas for future research. Thirteen studies were examined to determine what magnitude of effect was needed to identify an intervention as the most effective within a brief experimental…

Parental Involvement and Home Environment in Music: Current and Former Students from Selected Community Music Programs in Brazil and the United States

ERIC Educational Resources Information Center

Barnes, Gail V.; DeFreitas, Aureo; Grego, John

2016-01-01

The purpose of this study was to determine whether individuals' perceptions of parental involvement and home environment in music vary with nationality (Brazil/United States) and time frame (past/current). Past and current students from selected community music programs in the United States and Brazil completed the PI-HEM (Parental Involvement and…

The Role of Academic Motivation in High School Students’ Current and Lifetime Alcohol Consumption: Adopting a Self-Determination Theory Perspective*

PubMed Central

Wormington, Stephanie V.; Anderson, Kristen G.; Corpus, Jennifer Henderlong

2011-01-01

Objective: The current study investigated the relationship between different types of academic motives—specifically, intrinsic motivation, introjected regulation, and external regulation—and high school students' current and lifetime alcohol consumption. Method: One thousand sixty-seven high school students completed measures of academic motivation, other school-related factors, and lifetime and current alcohol consumption. Results: Using structural equation modeling, different types of motivation and school-related factors were differentially related to student drinking. Specifically, intrinsic motivation was negatively related to lifetime and current alcohol consumption. External regulation, on the other hand, was positively associated with current drinking. Grade point average was the only school-related factor related to student alcohol use. Conclusions: These findings suggest that motivation is an important construct to consider in predicting students’ alcohol use, even when other more commonly studied educational variables are considered. In addition, it supports the adoption of a motivation framework that considers different types of motivation in understanding the relationship between academic motivation and alcohol use. Suggestions for incorporating the self-determination model of motivation into studies of alcohol and substance use, as well as potential impacts on intervention efforts, are discussed. In particular, it may be important to foster only certain types of motivation, rather than all types of academically-focused motives, in efforts to deter alcohol use. PMID:22051210

The role of academic motivation in high school students' current and lifetime alcohol consumption: adopting a self-determination theory perspective.

PubMed

Wormington, Stephanie V; Anderson, Kristen G; Corpus, Jennifer Henderlong

2011-11-01

The current study investigated the relationship between different types of academic motives-specifically, intrinsic motivation, introjected regulation, and external regulation-and high school students' current and lifetime alcohol consumption. One thousand sixty-seven high school students completed measures of academic motivation, other school-related factors, and lifetime and current alcohol consumption. Using structural equation modeling, different types of motivation and school-related factors were differentially related to student drinking. Specifically, intrinsic motivation was negatively related to lifetime and current alcohol consumption. External regulation, on the other hand, was positively associated with current drinking. Grade point average was the only school-related factor related to student alcohol use. These findings suggest that motivation is an important construct to consider in predicting students' alcohol use, even when other more commonly studied educational variables are considered. In addition, it supports the adoption of a motivation framework that considers different types of motivation in understanding the relationship between academic motivation and alcohol use. Suggestions for incorporating the self-determination model of motivation into studies of alcohol and substance use, as well as potential impacts on intervention efforts, are discussed. In particular, it may be important to foster only certain types of motivation, rather than all types of academically-focused motives, in efforts to deter alcohol use.

Quantifying the uncertainties in life cycle greenhouse gas emissions for UK wheat ethanol

NASA Astrophysics Data System (ADS)

Yan, Xiaoyu; Boies, Adam M.

2013-03-01

Biofuels are increasingly promoted worldwide as a means for reducing greenhouse gas (GHG) emissions from transport. However, current regulatory frameworks and most academic life cycle analyses adopt a deterministic approach in determining the GHG intensities of biofuels and thus ignore the inherent risk associated with biofuel production. This study aims to develop a transparent stochastic method for evaluating UK biofuels that determines both the magnitude and uncertainty of GHG intensity on the basis of current industry practices. Using wheat ethanol as a case study, we show that the GHG intensity could span a range of 40-110 gCO2e MJ-1 when land use change (LUC) emissions and various sources of uncertainty are taken into account, as compared with a regulatory default value of 44 gCO2e MJ-1. This suggests that the current deterministic regulatory framework underestimates wheat ethanol GHG intensity and thus may not be effective in evaluating transport fuels. Uncertainties in determining the GHG intensity of UK wheat ethanol include limitations of available data at a localized scale, and significant scientific uncertainty of parameters such as soil N2O and LUC emissions. Biofuel polices should be robust enough to incorporate the currently irreducible uncertainties and flexible enough to be readily revised when better science is available.

Current Faculty Rank and Promotion Policies in Public Two-Year Colleges

ERIC Educational Resources Information Center

Hammons, James O.; Orf, Michael A.

2016-01-01

This study aimed: (a) to determine the prevalence of faculty rank among two-year colleges in the United States; (b) to identify the criteria used to determine faculty rank upon initial employment for transfer and vocational faculty; (c) to identify the criteria used to determine promotion for transfer and vocational faculty; and (d) to determine…

Early Twentieth Century Arrow, Javelin, and Dart Games of the Western Native American.

ERIC Educational Resources Information Center

Pesavento, Wilma J.

The general purpose of this study was to determine whether the traditional native American ball games continued to be positive culture traits of the American Indian in the early twentieth century. The investigation was centered about (1) determining the current arrow, javelin, and dart games of western native Americans, (2) determining the…

g-Factor of heavy ions: a new access to the fine structure constant.

PubMed

Shabaev, V M; Glazov, D A; Oreshkina, N S; Volotka, A V; Plunien, G; Kluge, H-J; Quint, W

2006-06-30

A possibility for a determination of the fine structure constant in experiments on the bound-electron g-factor is examined. It is found that studying a specific difference of the g-factors of B- and H-like ions of the same spinless isotope in the Pb region to the currently accessible experimental accuracy of 7 x 10(-10) would lead to a determination of the fine structure constant to an accuracy which is better than that of the currently accepted value. Further improvements of the experimental and theoretical accuracy could provide a value of the fine structure constant which is several times more precise than the currently accepted one.

METHOD DEVELOPMENT FOR THE DETERMINATION OF FORMALDEHYDE IN SAMPLES OF ENVIRONMENTAL ORIGIN

EPA Science Inventory

An analytical method was developed for the determination of formaldehyde in samples of environmental origin. After a review of the current literature, five candidate methods involving chemical derivatization were chosen for evaluation. The five derivatization reagents studied wer...

Investigation of the effect of resistivity on scrape off layer filaments using three-dimensional simulations

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

Easy, L., E-mail: le590@york.ac.uk; CCFE, Culham Science Centre, Abingdon OX14 3DB; Militello, F.

2016-01-15

The propagation of filaments in the Scrape Off Layer (SOL) of tokamaks largely determines the plasma profiles in the region. In a conduction limited SOL, parallel temperature gradients are expected, such that the resistance to parallel currents is greater at the target than further upstream. Since the perpendicular motion of an isolated filament is largely determined by balance of currents that flow through it, this may be expected to affect filament transport. 3D simulations have thus been used to study the influence of enhanced parallel resistivity on the dynamics of filaments. Filaments with the smallest perpendicular length scales, which weremore » inertially limited at low resistivity (meaning that polarization rather than parallel currents determines their radial velocities), were unaffected by resistivity. For larger filaments, faster velocities were produced at higher resistivities due to two mechanisms. First parallel currents were reduced and polarization currents were enhanced, meaning that the inertial regime extended to larger filaments, and second, a potential difference formed along the parallel direction so that higher potentials were produced in the region of the filament for the same amount of current to flow into the sheath. These results indicate that broader SOL profiles could be produced at higher resistivities.« less

Cross-study differences in the etiology of reading comprehension: A meta-analytical review of twin studies

PubMed Central

Little, Callie W; Haughbrook, Rasheda; Hart, Sara A

2016-01-01

Numerous twin studies have been published examining the genetic and environmental etiology of reading comprehension, though the etiological estimates may be influenced currently unidentified sample conditions (e.g., Tucker-Drob & Bates, 2015). The purpose of the current meta-analysis was to average the etiological influences of reading comprehension and to explore the potential moderators that may be influencing these estimates. Results revealed an average heritability estimate of h2 = .59, with significant variation in estimates across studies, suggesting potential moderation. Heritability was moderated by publication year, grade level, project, zygosity determination method, and response type. The average shared environmental estimate was c2 = .16, with publication year, grade and zygosity determination method acting as significant moderators. These findings support the large role of genetic influences on reading comprehension, and a small but significant role of shared environmental influences. The significant moderators of etiological influences within the current synthesis suggest our interpretation of how genes and environment influence reading comprehension should reflect aspects of study and sample. PMID:27630039

Internal vs Fishhook Hairpin DNA: Unzipping Locations and Mechanisms in the α-Hemolysin Nanopore

PubMed Central

2015-01-01

Studies on the interaction of hairpin DNA with the α-hemolysin (α-HL) nanopore have determined hairpin unzipping kinetics, thermodynamics, and sequence-dependent DNA/protein interactions. Missing from these results is a systematic study comparing the unzipping process for fishhook (one-tail) vs internal (two-tail) hairpins when they are electrophoretically driven from the cis to the trans side of α-HL via a 30-mer single-stranded tail. In the current studies, fishhook hairpins showed long unzipping times with one deep blockage current level. In contrast, the internal hairpins demonstrated relatively fast unzipping and a characteristic pulse-like current pattern. These differences were further explored with respect to stem length and sequence context. Further, a series of internal hairpins with asymmetric tails were studied, for which it was determined that a second tail longer than 12 nucleotides results in internal hairpin unzipping behavior, while tail lengths of 6 nucleotides behaved like fishhook hairpins. Interestingly, these studies were able to resolve a current difference of ∼6% between hairpin DNA immobilized in the nanopore waiting to unzip vs the translocating unzipped DNA, with the latter showing a deeper current blockage level. This demonstration of different currents for immobilized and translocating DNA has not been described previously. These results were interpreted as fishhook hairpins unzipping inside the vestibule, while the internal hairpins unzip outside the vestibule of α-HL. Lastly, we used this knowledge to study the unzipping of a long double-stranded DNA (>50 base pairs) outside the vestibule of α-HL. The conclusions drawn from these studies are anticipated to be beneficial in future application of nanopore analysis of nucleic acids. PMID:25333648

A global time-dependent model of thunderstorm electricity. I - Mathematical properties of the physical and numerical models

NASA Technical Reports Server (NTRS)

Browning, G. L.; Tzur, I.; Roble, R. G.

1987-01-01

A time-dependent model is introduced that can be used to simulate the interaction of a thunderstorm with its global electrical environment. The model solves the continuity equation of the Maxwell current, which is assumed to be composed of the conduction, displacement, and source currents. Boundary conditions which can be used in conjunction with the continuity equation to form a well-posed initial-boundary value problem are determined. Properties of various components of solutions of the initial-boundary value problem are analytically determined. The results indicate that the problem has two time scales, one determined by the background electrical conductivity and the other by the time variation of the source function. A numerical method for obtaining quantitative results is introduced, and its properties are studied. Some simulation results on the evolution of the displacement and conduction currents during the electrification of a storm are presented.

Why Study Time Does Not Predict Grade Point Average across College Students: Implications of Deliberate Practice for Academic Performance

ERIC Educational Resources Information Center

Plant, E. Ashby; Ericsson, K. Anders; Hill, Len; Asberg, Kia

2005-01-01

The current work draws upon the theoretical framework of deliberate practice in order to clarify why the amount of study by college students is a poor predictor of academic performance. A model was proposed where performance in college, both cumulatively and for a current semester, was jointly determined by previous knowledge and skills as well as…

The Current State of Marketing Activity among Higher Education Institutions.

ERIC Educational Resources Information Center

Newman, Cynthia M.

2002-01-01

Investigated the current state of marketing, marketing research, and planning practices at four-year higher education institutions. Builds upon previous studies by Blackburn (1979) and Goldgehn (1982 and 1989). Determined whether the use and apparent understanding of marketing and its attendant activities by admissions and enrollment management…

A Document Analysis of Teacher Evaluation Systems Specific to Physical Education

ERIC Educational Resources Information Center

Norris, Jason M.; van der Mars, Hans; Kulinna, Pamela; Kwon, Jayoun; Amrein-Beardsley, Audrey

2017-01-01

Purpose: The purpose of this document analysis study was to examine current teacher evaluation systems, understand current practices, and determine whether the instrumentation is a valid measure of teaching quality as reflected in teacher behavior and effectiveness specific to physical education (PE). Method: An interpretive document analysis…

Congenital Rubella: Clinical and Related Studies

ERIC Educational Resources Information Center

Menser, Margaret A.

1977-01-01

Briefly described are four studies currently being undertaken in Australia to determine the effectiveness of vaccination in the prevention of rubella and to examine the relationship between rubella and diabetes. (CL)

Review of current sonic boom studies.

NASA Technical Reports Server (NTRS)

Kane, E. J.

1973-01-01

Several aspects of the sonic boom phenomena are currently under investigation at The Boeing Co. This work, supported by the NASA and the FAA, includes an in-depth analysis of sonic boom measurements recorded at the BREN tower, a summary and evaluation of sonic boom investigations done in the last decade and a half, and configuration studies to determine practical lower bound sonic boom limits. The BREN tower test program yielded unique and valuable data because it was the first time that vertical profile measurements were made through caustics produced by maneuvers and atmospheric refraction. The objective of the second effort is to compile in a single reference an annotated abstract, including significant results, for each published sonic boom study and to provide a comprehensive review of the current state of the art to aid future researchers. The configuration work is devoted toward determining the feasibility of supersonic transport type airplanes with a primary design goal of acceptable sonic boom characteristics. Each of these investigations is briefly reviewed and significant results are discussed.

Determination of death after circulatory arrest by intensive care physicians: A survey of current practice in the Netherlands.

PubMed

Wind, Jentina; van Mook, Walther N K A; Dhanani, Sonny; van Heurn, Ernest W L

2016-02-01

Determination of death is an essential part of donation after circulatory death (DCD). We studied the current practices of determination of death after circulatory arrest by intensive care physicians in the Netherlands, the availability of guidelines, and the occurrence of the phenomenon of autoresuscitation. The Determination of Cardiac Death Practices in Intensive Care Survey was sent to all intensive care physicians. Fifty-five percent of 568 Dutch intensive care physicians responded. Most respondents learned death determination from clinical practice. The most commonly used tests for death determination were flat arterial line tracing, flat electrocardiogram (standard 3-lead electrocardiogram), and fixed and dilated pupils. Rarely used tests were absence pulse by echo Doppler, absent blood pressure by noninvasive monitoring, and unresponsiveness to painful stimulus. No diagnostic test or procedure was uniformly performed, but 80% of respondents perceived a need for standardization of death determination. Autoresuscitation was witnessed by 37%, after withdrawal of treatment or after unsuccessful resuscitation. Extensive variability in the practice of determining death after circulatory arrest exists, and a need for guidelines and standardization, especially if organ donation follows death, is reported. Autoresuscitation is reported; this observation requires attention in further prospective observational studies. Copyright © 2015 Elsevier Inc. All rights reserved.

Electric breakdown during the pulsed current spreading in the sand

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

Vasilyak, L. M., E-mail: vasilyak@ihed.ras.ru; Vetchinin, S. P.; Panov, V. A.

2016-03-15

Processes of spreading of the pulsed current from spherical electrodes and an electric breakdown in the quartz sand are studied experimentally. When the current density on the electrode exceeds the critical value, a nonlinear reduction occurs in the grounding resistance as a result of sparking in the soil. The critical electric field strengths for ionization and breakdown are determined. The ionization-overheating instability is shown to develop on the electrode, which leads to the current contraction and formation of plasma channels.

Demagnetization using a determined estimated magnetic state

DOEpatents

Denis, Ronald J; Makowski, Nathanael J

2015-01-13

A method for demagnetizing comprising positioning a core within the electromagnetic field generated by a first winding until the generated first electrical current is not substantially increasing, thereby determining a saturation current. A second voltage, having the opposite polarity, is then applied across the first winding until the generated second electrical current is approximately equal to the magnitude of the determined saturation current. The maximum magnetic flux within the core is then determined using the voltage across said first winding and the second current. A third voltage, having the opposite polarity, is then applied across the first winding until the core has a magnetic flux equal to approximately half of the determined maximum magnetic flux within the core.

Swarm observations of field-aligned currents associated with pulsating auroral patches

NASA Astrophysics Data System (ADS)

Gillies, D. M.; Knudsen, D.; Spanswick, E.; Donovan, E.; Burchill, J.; Patrick, M.

2015-11-01

We have performed a superposed epoch study of in situ field-aligned currents located near the edges of regions of pulsating aurora observed simultaneously using ground-based optical data from the Time History of Events and Macroscale Interactions during Substorms (THEMIS) all-sky imager (ASI) network and magnetometers on board the Swarm satellites. A total of nine traversals of Swarm over regions of pulsating aurora identified using THEMIS ASI were studied. We determined that in the cases where a clear boundary can be identified, strong downward currents are seen just poleward and equatorward of the pulsating patches. A downward current in the range of ~1-6 μA/m2 can be seen just poleward of the boundary. A weaker upward current of ~1-3 μA/m2 is observed throughout the interior of the patch. These observations indicate that currents carried by precipitating electrons within patches could close through horizontal currents and be returned at the edges, in agreement with Oguti and Hayashi (1984) and Hosokawa et al. (2010b). In addition to confirming these earlier results and adding to their statistical significance, the contribution of this study is to quantify the upward and downward current magnitudes, in some cases using two satellites traversing the same pulsating regions. Finally, we compare Swarm's two-satellite field-aligned current product to the single-satellite results and determine that the data product can be compromised in regions of pulsating aurora, a phenomenon that occurs over widespread regions and tends to persist for long periods of time. These results underscore the importance of electrical coupling between the ionosphere and magnetosphere in regions of patchy pulsating aurora.

Technique for determining the amount of hydrogen diffusing through a steel membrane

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

Kardash, N.V.; Batrakov, V.V.

1995-07-01

Hydrogen diffusion through steel membranes still attracts much attention from scientists, and during recent years new results have been reported. Hydrogen diffusion is usually studied in the cell designed by M.A. Devanathan, but there are also other techniques for determining hydrogen permeability, namely: from the change in the solution volume in a horizontal or gas microburette; from the hydrogen ionization current; from the penetration current; and from the buckling of the cathode. The authors developed an analytical method using autocatalytic titration for determining the amount of hydrogen passed through a steel membrane. The method is based on permanganatometry which ismore » widely used in analytical chemistry.« less

Current Understanding of the Binding Sites, Capacity, Affinity, and Biological Significance of Metals in Melanin

PubMed Central

Hong, Lian; Simon, John D.

2008-01-01

Metal chelation is often invoked as one of the main biological functions of melanin. In order to understand the interaction between metals and melanin, extensive studies have been carried out to determine the nature of the metal binding sites, binding capacity and affinity. These data are central to efforts aimed at elucidating the role metal binding plays in determining the physical, structural, biological, and photochemical properties of melanin. This article examines the current state of understanding of this field. PMID:17580858

Comparison of thruster configurations in attitude control systems. M.S. Thesis. Progress Report

NASA Technical Reports Server (NTRS)

Boland, J. S., III; Drinkard, D. M., Jr.; White, L. R.; Chakravarthi, K. R.

1973-01-01

Several aspects concerning reaction control jet systems as used to govern the attitude of a spacecraft were considered. A thruster configuration currently in use was compared to several new configurations developed in this study. The method of determining the error signals which control the firing of the thrusters was also investigated. The current error determination procedure is explained and a new method is presented. Both of these procedures are applied to each of the thruster configurations which are developed and comparisons of the two methods are made.

Investigation of the Motivation Level of Teachers Working at State Schools in Relation to Some Variables

ERIC Educational Resources Information Center

Can, Süleyman

2015-01-01

In order to give the best and accurate orientation to teachers working in school organizations, it seems to be necessary to determine their motivation level. Thus, the purpose of the current study is to determine the motivation level of teachers working in state elementary and secondary schools. Moreover, the study also looks at the relationships…

Muslim Women in Graduate Studies: Some Insights into the Accessibility of Higher Education for Minority Women Students

ERIC Educational Resources Information Center

Oplatka, Izhar; Lapidot, Orit

2012-01-01

Based on semi-structured interviews with 11 Muslim women graduate students in Israel, the current study provides insight into the determinants enabling this group of women in the Arab sector to apply for a second degree and succeed. Among these determinants are the family, the high school, the individual's personal drive for learning, the…

A theoretical approach to study the optical sensitivity of a MESFET

NASA Astrophysics Data System (ADS)

Dutta, Sutanu

2018-05-01

A theoretical model to study the optical sensitivity of a metal-semiconductor field effect transistor has been proposed for a relatively high drain field. An analytical expression of drain current of the device has been derived for a MESFET under optical illumination considering field dependent mobility of electrons across the channel. The variation of drain current with and without optical illumination has been studied with drain and gate voltages. The optical sensitivity of the drain current has been studied for different biasing conditions and gate lengths. In addition, the shift in threshold voltage of a MESFET under optical illumination is determined and optical sensitivity of the device in terms of its threshold voltage has been studied.

Use of a small overpotential approximation to analyze Geobacter sulfurreducens biofilm impedance

NASA Astrophysics Data System (ADS)

Babauta, Jerome T.; Beyenal, Haluk

2017-07-01

The electrochemical impedance of Geobacter sulfurreducens biofilms reflects the extracellular electron transfer mechanisms determining the rate of current output. Binned into two characteristic parameters, conductance and capacitance, biofilm impedance has received significant attention. The goal of this study was to evaluate a small overpotential approximation for extracellular electron transfer in G. sulfurreducens biofilms. Our motivation was to determine whether conductance over biofilm growth behaved linearly with respect to limiting current. Biofilm impedance was tracked during growth using electrochemical impedance spectroscopy (EIS) and electrochemical quartz crystal microbalance (eQCM). We showed that normalization of the biofilm impedance is useful for characterizing the changes during growth. When the conductance and capacitance were compared to the biofilm current, we found that: 1) conductance had a linear response and 2) constant phase elements (CPE) had a saturating response that coincided with the limiting current. We provided a framework using a simple iV relationship that predicted the conductance-current slope to be 9.57 V-1. CPEs showed more variability across biofilm replicates than conductance values. Although G. sulfurreducens biofilms were used here, other electrochemically active biofilms exhibiting catalytic waves could be studied using the same methods.

Ecotoxicology of mercury in fish and wildlife: Recent advances

USGS Publications Warehouse

Scheuhammer, Anton M.; Basu, Niladri; Evers, David C.; Heinz, Gary H.; Sandheinrich, Mark B.; Bank, Michael S.; edited by Bank, Michael S.; Bank, Michael S.

2012-01-01

A number of recent studies have documented subtle, yet potentially important effects of mercury on behavior, neurochemistry, and endocrine function in fish and wildlife at currently realistic levels of environmental exposure. Current levels of environmental methylmercury exposure are sufficient to cause significant biological impairment, both in individuals and in whole populations, in some ecosystems. Future toxicological studies on fish and wildlife will focus on linking biomarkers of methylmercury exposure and associated oxidative stress to effects on reproduction and population change; determining the genetic basis for mercury-related neurotoxic and other biological changes; determining the genetic basis for species differences in sensitivity to methylmercury; and linking toxic effects of methylmercury in individual animals to population-level changes.

Three-meter telescope study

NASA Technical Reports Server (NTRS)

Wissinger, A.; Scott, R. M.; Peters, W.; Augustyn, W., Jr.; Arnold, R.; Offner, A.; Damast, M.; Boyce, B.; Kinnaird, R.; Mangus, J. D.

1971-01-01

A means is presented whereby the effect of various changes in the most important parameters of a three meter aperature space astronomy telescope can be evaluated to determine design trends and to optimize the optical design configuration. Methods are defined for evaluating the theoretical optical performance of axisymmetric, centrally obscured telescopes based upon the intended astronomy research usage. A series of design parameter variations is presented to determine the optimum telescope configuration. The design optimum requires very fast primary mirrors, so the study also examines the current state of the art in fabricating large, fast primary mirrors. The conclusion is that a 3-meter primary mirror having a focal ratio as low as f/2 is feasible using currently established techniques.

Using 3d Bim Model for the Value-Based Land Share Calculations

NASA Astrophysics Data System (ADS)

Çelik Şimşek, N.; Uzun, B.

2017-11-01

According to the Turkish condominium ownership system, 3D physical buildings and its condominium units are registered to the condominium ownership books via 2D survey plans. Currently, 2D representations of the 3D physical objects, causes inaccurate and deficient implementations for the determination of the land shares. Condominium ownership and easement right are established with a clear indication of land shares (condominium ownership law, article no. 3). So, the land share of each condominium unit have to be determined including the value differences among the condominium units. However the main problem is that, land share has often been determined with area based over the project before construction of the building. The objective of this study is proposing a new approach in terms of value-based land share calculations of the condominium units that subject to condominium ownership. So, the current approaches and its failure that have taken into account in determining the land shares are examined. And factors that affect the values of the condominium units are determined according to the legal decisions. This study shows that 3D BIM models can provide important approaches for the valuation problems in the determination of the land shares.

Circadian gene expression in peripheral blood leukocytes of rotating night shift nurses.

PubMed

Reszka, Edyta; Peplonska, Beata; Wieczorek, Edyta; Sobala, Wojciech; Bukowska, Agnieszka; Gromadzinska, Jolanta; Lie, Jenny-Anne; Kjuus, Helge; Wasowicz, Wojciech

2013-03-01

It has been hypothesized that the underlying mechanism of elevated breast cancer risk among long-term, night-working women involves circadian genes expression alteration caused by exposure to light at night and/or irregular work hours. The aim of the present study was to determine the effect of rotating night shift work on expression of selected core circadian genes. The cross-sectional study was conducted on 184 matched nurses and midwives, who currently work either day or rotating night shifts, to determine the effect of irregular work at night on circadian gene expression in peripheral blood leukocytes. Transcript levels of BMAL1, CLOCK, CRY1, CRY2, PER1, PER2, and PER3 were determined by means of quantitative real-time polymerase chain reaction (PCR). After adjusting for hour of blood collection, there were no statistically significant changes of investigated circadian genes among nurses and midwives currently working rotating night shifts compared to nurses working day shifts. The highest expression of PER1 messenger ribonucleic acid (mRNA) was observed for women currently working shifts who had worked >15 years in rotating night shift work. PER1 gene expression was associated with the lifetime duration of rotating night shift work among women currently working night shifts (P=0.04). PER1 and PER3 transcript levels in blood leukocytes were significantly down-regulated in the later versus early hours of the morning between 06.00-10.00 hours (β-coefficient -0.226, P=0.001 and β-coefficient -0.181, P<0.0001, respectively). These results suggest that current rotating night shift work does not affect circadian gene expression in human circulating leukocytes. In analysis of the peripheral clock in human studies, the hour of blood collection should be precisely specified.

Survey on utility technology of a tidal and ocean current energy

NASA Astrophysics Data System (ADS)

Hirose, Manabu; Kadoyu, Masataka; Tanaka, Hiroyoshi

1987-06-01

A study is made to show the current technological levels in Japan and other nations regarding the conversion of tidal current or ocean current energy to electric power and to determine the latent energy quantities and energy-related characteristics of tidal and ocean currents. In Japan, relatively large-scale experiments made so far mostly used one of the following three types of devices: Savonius-wheel type, Darrieus-wheel type, and cross-flow-wheel type. Field experiments of tidal energy conversion have been performed at the Naruto and Kurushima Straits. The energy in the Kuroshio current is estimated at about 170 billion kWh per year. Ocean current energy does not undergo large seasonal variations. The total energy in major straits and channels in the Inland Sea and other sea areas to the west is estimated at about 124 billion kWh per year. Tidal current energy shows large seasonal variations, but it is possible to predict the changes. A survey is made to determine energy-related characteristics of a tidal current at Chichino-seto, Kagoshima Prefecture. At Chichino-seto, the flow velocity ranges from 0 to 2.2m/s, with a latent tidal current energy of about 70 kW, of which about 20 kW can actually be utilized.

Determination of the amount of Cs-137 in the sea water obtained from the Dardanelles

NASA Astrophysics Data System (ADS)

Ataseven, D.; Şen, S.

2017-02-01

After the Chernobyl accident, high concentrations of Cs-137 radioisotope reached the Black Sea through dry and wet fallout. Therefore, a number of studies were performed to determine the current activity of Cs-137 near this region in the sea water and in marine organisms. Cs-137 activity was determined in the Dardanelles sea water taken from three separate locations and two different depths for each location. The old data base obtained in our previous studies was updated.

Effect of Micro-Teaching Practices with Concrete Models on Pre-Service Mathematics Teachers' Self-Efficacy Beliefs about Using Concrete Models

ERIC Educational Resources Information Center

Ünlü, Melihan

2018-01-01

The purpose of the current study was to investigate the effect of micro-teaching practices with concrete models on the pre-service teachers' self-efficacy beliefs about using concrete models and to determine the opinions of the pre-service teachers about this issue. In the current study, one of the mixed methods, the convergent design (embedded)…

Backup of Renewable Energy for an Electrical Island: Case Study of Israeli Electricity System—Current Status

PubMed Central

Fakhouri, A.; Kuperman, A.

2014-01-01

The paper focuses on the quantitative analysis of Israeli Government's targets of 10% renewable energy penetration by 2020 and determining the desired methodology (models) for assessing the effects on the electricity market, addressing the fact that Israel is an electricity island. The main objective is to determine the influence of achieving the Government's goals for renewable energy penetration on the need for backup in the Israeli electricity system. This work presents the current situation of the Israeli electricity market and the study to be taken in order to assess the undesirable effects resulting from the intermittency of electricity generated by wind and solar power stations as well as presents some solutions to mitigating these phenomena. Future work will focus on a quantitative analysis of model runs and determine the amounts of backup required relative to the amount of installed capacity from renewable resources. PMID:24624044

Backup of renewable energy for an electrical island: case study of Israeli electricity system--current status.

PubMed

Fakhouri, A; Kuperman, A

2014-01-01

The paper focuses on the quantitative analysis of Israeli Government's targets of 10% renewable energy penetration by 2020 and determining the desired methodology (models) for assessing the effects on the electricity market, addressing the fact that Israel is an electricity island. The main objective is to determine the influence of achieving the Government's goals for renewable energy penetration on the need for backup in the Israeli electricity system. This work presents the current situation of the Israeli electricity market and the study to be taken in order to assess the undesirable effects resulting from the intermittency of electricity generated by wind and solar power stations as well as presents some solutions to mitigating these phenomena. Future work will focus on a quantitative analysis of model runs and determine the amounts of backup required relative to the amount of installed capacity from renewable resources.

Lessons Learned from Decontamination Experiences

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

Sorensen, JH

2000-11-16

This interim report describes a DOE project currently underway to establish what is known about decontamination of buildings and people and the procedures and protocols used to determine when and how people or buildings are considered ''clean'' following decontamination. To fulfill this objective, the study systematically examined reported decontamination experiences to determine what procedures and protocols are currently employed for decontamination, the timeframe involved to initiate and complete the decontamination process, how the contaminants were identified, the problems encountered during the decontamination process, how response efforts of agencies were coordinated, and the perceived social psychological effects on people who weremore » decontaminated or who participated in the decontamination process. Findings and recommendations from the study are intended to aid decision-making and to improve the basis for determining appropriate decontamination protocols for recovery planners and policy makers for responding to chemical and biological events.« less

Velocity profile, water-surface slope, and bed-material size for selected streams in Colorado

USGS Publications Warehouse

Marchand, J.P.; Jarrett, R.D.; Jones, L.L.

1984-01-01

Existing methods for determining the mean velocity in a vertical sampling section do not address the conditions present in high-gradient, shallow-depth streams common to mountainous regions such as Colorado. The report presents velocity-profile data that were collected for 11 streamflow-gaging stations in Colorado using both a standard Price type AA current meter and a prototype Price Model PAA current meter. Computational results are compiled that will enable mean velocities calculated from measurements by the two current meters to be compared with each other and with existing methods for determining mean velocity. Water-surface slope, bed-material size, and flow-characteristic data for the 11 sites studied also are presented. (USGS)

Study of Integrated USV/UUV Observation System Performance in Monterey Bay

DTIC Science & Technology

2017-09-01

5 IV. EXPERIMENTAL SETUP... quasi -stationary at depth in low-current environments. This thesis evaluates the performance of deep sensors in determining behavior of a moving source...acoustic sensors that would be quasi -stationary receivers when in drift mode at depth in low current environments. One key advantage to this technique is

Who Should Become a Teacher? Current Student Selection-Retention Policies of Teacher Education Institutions.

ERIC Educational Resources Information Center

Brubaker, Harold A.

This study (1) describes student selection and retention procedures currently used by North Central Association colleges and universities which are accredited by the National Council for the Accreditation of Teacher Education, and (2) determines student selection and retention procedures which administrators of teacher education programs at the…

Current Status of the Matson Evaluation of Drug Side Effects (MEDS)

ERIC Educational Resources Information Center

Matson, Johnny L.; Cervantes, Paige E.

2013-01-01

The Matson Evaluation of Drug Side Effects (MEDS) is currently the best established and most researched measure of drug side effects in the intellectual disability (ID) literature. Initial research was conducted on its psychometric properties such as reliability and validity. More recent research studies have used the measure to determine the…

A Review of Meta-Analyses in Education: Methodological Strengths and Weaknesses

ERIC Educational Resources Information Center

Ahn, Soyeon; Ames, Allison J.; Myers, Nicholas D.

2012-01-01

The current review addresses the validity of published meta-analyses in education that determines the credibility and generalizability of study findings using a total of 56 meta-analyses published in education in the 2000s. Our objectives were to evaluate the current meta-analytic practices in education, identify methodological strengths and…

Socioeconomic Correlates of Current and Regular Smoking among College Students in Rhode Island

ERIC Educational Resources Information Center

Clarkin, Patrick F.; Tisch, Linda A.; Glicksman, Arvin S.

2008-01-01

Objective: The objective of this study was to determine how sociodemographic variables, in particular socioeconomic status, correlate with current and regular smoking among college students in Rhode Island. Participants and Methods: Over a 4-year period (academic year 2000-2001 to 2003-2004), the authors examined sociodemographic correlates of…

Travel and Tourism Industry: Program Options for City College of San Francisco.

ERIC Educational Resources Information Center

City Coll. of San Francisco, CA.

In an effort to determine the current occupational outlook and resulting implications for education and training, the City College of San Francisco (CCSF), in California, undertook a study of current trends in the travel and tourism industry. This report provides findings from the project, which involved consultation with local and national…

Determining heavy metals in spent compact fluorescent lamps (CFLs) and their waste management challenges: Some strategies for improving current conditions

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

Taghipour, Hassan, E-mail: hteir@yahoo.com; Amjad, Zahra; Jafarabadi, Mohamad Asghari

2014-07-15

Highlights: • Heavy metals in spent compact fluorescent lamps (CFLs) determined. • Current waste management condition of CFLs in Iran assessed. • Currently, waste of CFLs is disposed by municipal waste stream in waste landfills. • We propose extended producer responsibility (EPR) for CFLs waste management. - Abstract: From environmental viewpoint, the most important advantage of compact fluorescent lamps (CFLs) is reduction of green house gas emissions. But their significant disadvantage is disposal of spent lamps because of containing a few milligrams of toxic metals, especially mercury and lead. For a successful implementation of any waste management plan, availability ofmore » sufficient and accurate information on quantities and compositions of the generated waste and current management conditions is a fundamental prerequisite. In this study, CFLs were selected among 20 different brands in Iran. Content of heavy metals including mercury, lead, nickel, arsenic and chromium was determined by inductive coupled plasma (ICP). Two cities, Tehran and Tabriz, were selected for assessing the current waste management condition of CFLs. The study found that waste generation amount of CFLs in the country was about 159.80, 183.82 and 153.75 million per year in 2010, 2011 and 2012, respectively. Waste generation rate of CFLs in Iran was determined to be 2.05 per person in 2012. The average amount of mercury, lead, nickel, arsenic and chromium was 0.417, 2.33, 0.064, 0.056 and 0.012 mg per lamp, respectively. Currently, waste of CFLs is disposed by municipal waste stream in waste landfills. For improving the current conditions, we propose by considering the successful experience of extended producer responsibility (EPR) in other electronic waste management. The EPR program with advanced recycling fee (ARF) is implemented for collecting and then recycling CFLs. For encouraging consumers to take the spent CFLs back at the end of the products’ useful life, a proportion of ARF (for example, 50%) can be refunded. On the other hand, the government and Environmental Protection Agency should support and encourage recycling companies of CFLs both technically and financially in the first place.« less

Ionic calcium determination in skim milk with molecular probes and front-face fluorescence spectroscopy: simple linear regression.

PubMed

Gangidi, R R; Metzger, L E

2006-11-01

The purpose of this study was to determine if the ionic calcium content of skim milk could be determined using molecular probes and front-face fluorescence spectroscopy. Current methods for determining ionic calcium are not sensitive, overestimate ionic calcium, or require complex procedures. Molecular probes designed specifically for measuring ionic calcium could potentially be used to determine the ionic calcium content of skim milk. The goal of the current study was to develop foundation methods for future studies to determine ionic calcium directly in skim milk and other dairy products with molecular probes and fluorescence spectroscopy. In this study, the effect of pH on calcium-sensitive fluorescent probe (Rhod-5N and Fluo-5N) performance using various concentrations of skim milk was determined. The pH of diluted skim milk (1.9 to 8.9% skim milk), was adjusted to either 6.2 or 7.0, after which the samples were analyzed with fluorescent probes (1 microM) and front-face fluorescence spectroscopy. The ionic calcium content of each sample was also determined using a calcium ion-selective electrode. The results demonstrated that the ionic calcium content of each sample was highly correlated (R2 > 0.989) with the fluorescence intensities of the probe-calcium adduct using simple linear regression. Higher than suggested ionic calcium contents of 1,207 and 1,973 microM were determined with the probes (Fluo-5N and Rhod-5N) in diluted skim milk with pH 7.0 and 6.2, respectively. The fluorescence intensity of the probe-calcium adduct decreased with a decrease in pH for the same ionic calcium concentration. This study demonstrates that Fluo-5N and Rhod-5N can be used to determine the ionic-calcium content of diluted milk with front-face fluorescence spectroscopy. Furthermore, these probes may also have the potential to determine the ionic calcium content of undiluted skim milk.

More bark than bite: Comparative studies are needed to determine the importance of canine zoonoses in Aboriginal communities. A critical review of published research.

PubMed

Smout, F; Schrieber, L; Speare, R; Skerratt, L F

2017-11-01

The objective of this review was to identify and critique over forty years of peer-reviewed literature concerned with the transmission of canine zoonoses to Aboriginal people and determine the zoonotic organisms documented in dogs in Australian Aboriginal communities. A systematic literature search of public health, medical and veterinary databases identified 19 articles suitable for critical appraisal. Thirteen articles documented the occurrence of recognized zoonotic organisms in dogs in Aboriginal communities, including Toxocara canis, Dirofilaria immitis, Streptococcus dysgalactiae, Rickettsia felis, Sarcoptes scabiei and Giardia. Currently, there is definitive evidence indicating that dogs act as a reservoir for human scabies in Aboriginal communities. However, there is a need for large-scale, high-quality, comparative studies of dogs and humans from the same household to assess the occurrence and importance of transmission of S. scabiei and other diseases between dogs and humans. These studies should use current genetic and molecular techniques along with traditional techniques to identify and type organisms in order to better understand their epidemiology. This review has revealed that there is a lack of high-quality comparative studies to determine whether dogs are contributing to human disease by transmitting zoonoses. Our recommendations differ significantly from current public health policy and may have substantial implications for human and dog health. © 2017 Blackwell Verlag GmbH.

Determination of torque speed current characteristics of a brushless DC motor by utilizing back-EMF of non-energized phase

NASA Astrophysics Data System (ADS)

Jang, G. H.; Yeom, J. H.; Kim, M. G.

2007-03-01

This paper presents a method to determine the torque constant and the torque-speed-current characteristics of a brushless DC (BLDC) motor by utilizing back-EMF variation of nonenergized phase. It also develops a BLDC motor controller with a digital signal processor (DSP) to monitor its current, voltage and speed in real time. Torque-speed-current characteristics of a BLDC motor are determined by using the proposed method and the developed controller. They are compared with the torque-speed-current characteristics measured by dynamometer experimentally. This research shows that the proposed method is an effective method to determine the torque constant and the torque-speed-current characteristics of the BLDC motor without using dynamometer.

Concordance between current job and usual job in occupational and industry groupings: assessment of the 2010 national health interview survey.

PubMed

Luckhaupt, Sara E; Cohen, Martha A; Calvert, Geoffrey M

2013-09-01

To determine whether current job is a reasonable surrogate for usual job. Data from the 2010 National Health Interview Survey were utilized to determine concordance between current and usual jobs for workers employed within the past year. Concordance was quantitated by kappa values for both simple and detailed industry and occupational groups. Good agreement is considered to be present when kappa values exceed 60. Overall kappa values ± standard errors were 74.5 ± 0.5 for simple industry, 72.4 ± 0.5 for detailed industry, 76.3 ± 0.4 for simple occupation, 73.7 ± 0.5 for detailed occupation, and 80.4 ± 0.6 for very broad occupational class. Sixty-five of 73 detailed industry groups and 78 of 81 detailed occupation groups evaluated had good agreement between current and usual jobs. Current job can often serve as a reliable surrogate for usual job in epidemiologic studies.

Concordance Between Current Job and Usual Job in Occupational and Industry Groupings

PubMed Central

Luckhaupt, Sara E.; Cohen, Martha A.; Calvert, Geoffrey M.

2015-01-01

Objective To determine whether current job is a reasonable surrogate for usual job. Methods Data from the 2010 National Health Interview Survey were utilized to determine concordance between current and usual jobs for workers employed within the past year. Concordance was quantitated by kappa values for both simple and detailed industry and occupational groups. Good agreement is considered to be present when kappa values exceed 60. Results Overall kappa values ± standard errors were 74.5 ± 0.5 for simple industry, 72.4 ± 0.5 for detailed industry, 76.3 ± 0.4 for simple occupation, 73.7 ± 0.5 for detailed occupation, and 80.4 ± 0.6 for very broad occupational class. Sixty-five of 73 detailed industry groups and 78 of 81 detailed occupation groups evaluated had good agreement between current and usual jobs. Conclusions Current job can often serve as a reliable surrogate for usual job in epidemiologic studies. PMID:23969506

Intra-tidal variability of the vertical current structure in the western Dutch Wadden Sea

NASA Astrophysics Data System (ADS)

de Vries, Jurre; Ridderinkhof, Herman; van Aken, Hendrik

2014-05-01

Long-term velocity measurements are presented which were collected during three different seasons at one single location in an estuarine basin of the western Dutch Wadden Sea. These data are used to investigate the processes that determine the variability of the vertical current structure in the western Dutch Wadden Sea, in combination with simplified model runs using the one-dimensional water column model GETM (http://www.getm.eu/). Jay and Musiak [1996] were the first to suggest that intra-tidal variations in the vertical current might be important in determining the residual circulation patterns. More research [e.g. Stacey et al., 2001; Burchard and Hetland, 2010] has supported this hypothesis. Recently, lateral processes have been shown to influence the vertical current structure of alongstream velocity and hence the residual circulation [e.g. Lerczak and Geyer, 2004; Burchard and Schuttelaars, 2012]. Therefore to better understand the tidal dynamics in the western Dutch Wadden Sea, it is crucial to understand the processes that determine the vertical current structure. The two main findings of this study are that the complex bathymetry at the study site seems to produce an intra-tidal asymmetry in near-bed velocities and secondly that cross-stream processes strongly modify the current structure during late flood. Near-bed velocity and the bed roughness are greater during ebb than during flood. The GETM simulations suggest that vertical mixing during ebb is sufficient to destroy vertical stratification generated by classical tidal straining. The cross-stream current during late flood generate vertical stratification and drive an early reversal of the flood current near the surface. Therefore, it is hypothesized that this processes might increase the residual estuarine circulation at the study site. References - Burchard, H., Hetland, R.D. (2010), Quantifying the contributions of tidal straining and gravitational circulation to residual circulation in periodically stratified tidal estuaries, Journal of Physical Oceanography, 40(6), 1243-1262 - Burchard, H., Schuttelaars, H.M. (2012), Analysis of tidal straining as driver for estuarine circulation in well-mixed estuaries, Journal of Physical Oceanography, 42(2), 261-271 - Jay, D.A., Musiak, J.D. (1996), Internal tidal asymmetry in channel flows' origins and consequences, Coastal and Estuarine Studies, 50, 211-249 - Stacey, M.T., Burau J.R., Monismith, S.G. (2001), Creation of residual flows in a partially stratified estuary, Journal of Physical Oceanography, 34, 1410-1428

Conductive paths through polycrystalline BaTiO{sub 3}: Scanning probe microscopy study

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

Ayvazian, Talin; Bersuker, Gennadi; Lingley, Zachary R.

2016-08-15

The microstructural features determining the leakage current through polycrystalline BaTiO{sub 3} films are investigated using Conductive Atomic Force Microscopy. Grain boundaries are found to be the dominant conductive paths compared to the conduction through the grains. Grain boundary currents are observed to reversibly rise with the increase of the applied DC voltages, indicating that the current is controlled by a field-activated charge transport process.

Determination of eddy current response with magnetic measurements.

PubMed

Jiang, Y Z; Tan, Y; Gao, Z; Nakamura, K; Liu, W B; Wang, S Z; Zhong, H; Wang, B B

2017-09-01

Accurate mutual inductances between magnetic diagnostics and poloidal field coils are an essential requirement for determining the poloidal flux for plasma equilibrium reconstruction. The mutual inductance calibration of the flux loops and magnetic probes requires time-varying coil currents, which also simultaneously drive eddy currents in electrically conducting structures. The eddy current-induced field appearing in the magnetic measurements can substantially increase the calibration error in the model if the eddy currents are neglected. In this paper, an expression of the magnetic diagnostic response to the coil currents is used to calibrate the mutual inductances, estimate the conductor time constant, and predict the eddy currents response. It is found that the eddy current effects in magnetic signals can be well-explained by the eddy current response determination. A set of experiments using a specially shaped saddle coil diagnostic are conducted to measure the SUNIST-like eddy current response and to examine the accuracy of this method. In shots that include plasmas, this approach can more accurately determine the plasma-related response in the magnetic signals by eliminating the field due to the eddy currents produced by the external field.

78 FR 45941 - Changes in Flood Hazard Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-30

... (hereinafter referred to as flood hazard determinations) as shown on the indicated Letter of Map Revision (LOMR... Insurance Rate Maps (FIRMs), and in some cases the Flood Insurance Study (FIS) reports, currently in effect... respective Community Map Repository address listed in the table below and online through the FEMA Map Service...

Pedagogical Practices and Counselor Self-Efficacy: A Mixed Methods Investigations

ERIC Educational Resources Information Center

Brogan, Justin R.

2009-01-01

The current study investigated the Lecture Teaching Method and Socratic Teaching Method to determine if there was a relationship between pedagogical methods and Counselor Self-Efficacy (CSE). A course in Advanced Professional Development was utilized to determine if teaching methods could affect student perceptions of competence to practice…

Determining Indirect Cost Rates in Research Libraries. SPEC Kit 34.

ERIC Educational Resources Information Center

Association of Research Libraries, Washington, DC. Office of Management Studies.

This kit prepared by the Association of Research Libraries (ARL) contains 15 primary source documents on determining indirect cost rates in research libraries. The kit comprises: (1) six library cost studies and surveys, "Allocation of Library Expenditures to Research and Instruction" (University of Pennsylvania), "Sampling of Current Monograph…

Determining The Dispersibility Of South Louisiana Crude Oil By Eight Oil Dispersant Products Listed On The NCP Product Schedule

EPA Science Inventory

We recently conducted a laboratory study to measure the dispersion effectiveness of eight dispersants currently listed on the National Contingency Plan Product Schedule. Results are useful in determining how many commercial dispersant products would have been effective for use o...

Self-Determination: Hearing the Voices of Adults with Physical Disabilities

ERIC Educational Resources Information Center

Stoner, Julia B.; Angell, Maureen E.; House, Jennifer J.; Goins, Kelly

2006-01-01

Most current self-determination research focuses on adults with developmental disabilities but neglects adults with physical disabilities who depend on caregivers for many or most aspects of daily living. This study investigated the perceptions of 12 adults with physical disabilities related to their self-reported abilities and opportunities to…

Determination of Pre-Service Science Teachers' Level of Awareness of Environmental Ethics in Relation to Different Variables

ERIC Educational Resources Information Center

Keles, Özgül; Özer, Nilgün

2016-01-01

The purpose of the current study is to determine the pre-service science teachers' awareness levels of environmental ethics in relation to different variables. The sampling of the present study is comprised of 1,023 third and fourth year pre-service science teachers selected from 12 different universities in the spring term of 2013-2014 academic…

The Use of Nonprint Media in the Public Schools of Maryland: An Exploratory Study. Final Report.

ERIC Educational Resources Information Center

Liesener, James W.

The primary objective of this project was the study of the utilization of nonprint media in the public schools of the State of Maryland in order to determine current patterns and identify developing trends in the use of media materials and equipment. Secondary objectives were to determine variations in patterns of use of media materials and…

Study of plasmasphere dynamics using incoherent scatter data from Chatanika, Alaska radar facility

NASA Technical Reports Server (NTRS)

Shelley, E. G.

1975-01-01

Results of the study of Chatanika incoherent scatter radar data and Lockheed Palo Alto Research Laboratory satellite data are reported. Specific topics covered include: determination of the effective recombination coefficient in the auroral E region; determination of the location of the auroral oval; auroral boundary characteristics; and the relationship of auroral current systems, particle precipitation, visual aurora, and radar aurora.

An Exploratory Study of the Influence of the Advancement via Individual Determination (AVID) Program on African American Young Men in Southeastern North Carolina

ERIC Educational Resources Information Center

Parker, Michele A.; Eliot, Jessica; Tart, Michael

2013-01-01

This is a qualitative study of how the Advancement Via Individual Determination (AVID) program influenced 9 African American young men in southeastern North Carolina. To understand the impact of the program, a cross-section of current and past AVID participants were interviewed. The African American male students were asked about their attitudes…

Feasibility Study for Hotel/Motel Career Program for Harper College. Volume XIX, No. 1.

ERIC Educational Resources Information Center

Lucas, John A.; And Others

In spring 1990, a study was conducted at William Rainey Harper College (WRHC) to determine the feasibility of adding a career program in Hotel/Motel Management (HMM) to the current Food Service Program. Surveys were sent to 53 hotels and motels in the WRHC service area to determine employment demands that would affect the hiring of graduates of…

PAIRED-CITY STUDY TO DETERMINE THE CONTRIBUTION OF SOURCE WATER TYPE TO THE ENDEMIC LEVEL OF MICROBIAL DISEASE

EPA Science Inventory

Paired-City Study to Determine the Contribution of Source Water Type to the Endemic Level of Microbial Disease

F Frost PhD, T Kunde MPH, L Harter PhD, T Muller MS, GF Craun PE MPH, RL Calderon MPH PhD

ABSTRACT

Context: The effectiveness of current drinking...

Determination of complex formation constants by phase sensitive alternating current polarography: Cadmium-polymethacrylic acid and cadmium-polygalacturonic acid.

PubMed

Garrigosa, Anna Maria; Gusmão, Rui; Ariño, Cristina; Díaz-Cruz, José Manuel; Esteban, Miquel

2007-10-15

The use of phase sensitive alternating current polarography (ACP) for the evaluation of complex formation constants of systems where electrodic adsorption is present has been proposed. The applicability of the technique implies the previous selection of the phase angle where contribution of capacitive current is minimized. This is made using Multivariate Curve Resolution by Alternating Least Squares (MCR-ALS) in the analysis of ACP measurements at different phase angles. The method is checked by the study of the complexation of Cd by polymethacrylic (PMA) and polygalacturonic (PGA) acids, and the optimal phase angles have been ca. -10 degrees for Cd-PMA and ca. -15 degrees for Cd-PGA systems. The goodness of phase sensitive ACP has been demonstrated comparing the determined complex formation constants with those obtained by reverse pulse polarography, a technique that minimizes the electrode adsorption effects on the measured currents.

Measuring gravity currents in the Chicago River, Chicago, Illinois

USGS Publications Warehouse

Oberg, K.A.; Czuba, J.A.; Johnson, K.K.

2008-01-01

Recent studies of the Chicago River have determined that gravity currents are responsible for persistent bidirectional flows that have been observed in the river. A gravity current is the flow of one fluid within another caused by a density difference between the fluids. These studies demonstrated how acoustic Doppler current profilers (ADCP) can be used to detect and characterize gravity currents in the field. In order to better understand the formation and evolution of these gravity currents, the U.S. Geological Survey (USGS) has installed ADCPs and other instruments to continuously measure gravity currents in the Chicago River and the North Branch Chicago River. These instruments include stage sensors, thermistor strings, and both upward-looking and horizontal ADCPs. Data loggers and computers installed at gaging stations along the river are used to collect data from these instruments and transmit them to USGS offices. ?? 2008 IEEE.

Porosity determination of thermal barrier coatings

NASA Technical Reports Server (NTRS)

Van Roode, Mark; Beardsley, Brad

1988-01-01

Coating porosity is believed to be a critical factor for the thermal conductivity of thermal barrier coatings (TBCs). A number of different techniques have been used to determine the porosities of thermal barrier coatings for diesel applications as part of a NASA/DOE sponsored study. A comparison is made between methods based on water immersion, optical microscopy, eddy current thickness measurements, and Archimedes principle for TBC porosity determination.

42 CFR 90.8 - Conduct of health assessments and health effects studies.

Code of Federal Regulations, 2011 CFR

2011-10-01

... site visit in connection with a health assessment or health effects study. The ATSDR representative may... release for the limited purpose of determining the existence of current or potential health problems. ...

Truckers' parking/rest facility study.

DOT National Transportation Integrated Search

2008-07-01

This study examined the current state of truck parking and rest area facilities in the Northeast Illinois Region to determine if : and how problems from truck parking affect freight transportation infrastructure, safety, and the regions economy an...

Mass transfer study on the electrochemical removal of copper ions from synthetic effluents using reticulated vitreous carbon.

PubMed

Britto-Costa, Pedro H; Ruotolo, Luís Augusto M

2013-01-01

Porous electrodes have been successfully used for metal electrodeposition from diluted aqueous solution due to their high porosity and specific surface area, which lead to high mass transfer rates. This work studies the mass transfer of copper electrodeposition on reticulated vitreous carbon in a flow reactor without membrane. The flow configuration, otherwise the filter-press electrochemical reactors, was designed in order to minimize the pressure drop. The mass transfer coefficient was determined by voltammetric and galvanostatic electrodeposition. In the voltammetric experiments a Luggin capillary was used to measure the current-potential curves and to determine the limiting current (and, consequently, the mass transfer coefficient). In the galvanostatic experiments the concentration-time curves were obtained and considering a limiting current kinetics model, the mass transfer coefficient (k(m)) was determined for different flow velocities. The results showed that both methods give similar values of k(m), thus the voltammetric method can be recommended because it is faster and simpler. Finally, the reactor performance was compared with others from literature, and it was observed that the proposed reactor design has high Sherwood numbers similar to other reactor configurations using membranes and reticulated vitreous carbon electrodes.

School gardens and adolescent nutrition and BMI: Results from a national, multilevel study.

PubMed

Utter, Jennifer; Denny, Simon; Dyson, Ben

2016-02-01

The aim of the current study was to determine the impact of school gardens on student eating behaviors, physical activity and BMI in New Zealand secondary schools. The current study also aimed to determine if school gardens could buffer the association between household poverty and adolescent BMI. Data were drawn from a national study of the health and wellbeing of New Zealand secondary school students (n=8500) conducted in 2012. Multilevel regression models were used to determine the association between school gardens (school-level) and student nutrition behaviors, physical activity and measured BMI (student-level). Approximately half of secondary schools had a fruit/vegetable garden for students to participate in. School gardens were associated with lower student BMI (p=0.01) and lower prevalence of overweight (p<0.01). School gardens appear to have a positive impact on student health. Future research may explore how school gardens are implemented to better understand their impact and to extend the benefits beyond the school community. Copyright © 2015 Elsevier Inc. All rights reserved.

Hemorrhage Control for Major Traumatic Vascular Injuries

DTIC Science & Technology

2017-10-01

subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO...aims: 1) Determine current practice patterns for the treatment of patients with NCTH among 4 clinical sites using a retrospective study design (Phase...competency, and training issues for catheter-based hemorrhage control (Phase 1b); 3) Conduct a prospective 4-site observational study to test the hypothesis

EPA office of solid waste (OSW) report to Congress

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

Derkics, D.

1996-12-31

An EPA Office of Solid Waste Report to Congress is presented in outline form. The following topics are discussed: special waste chronology; statutory hazardous waste exemption; 1988 report to Congress findings; 1993 regulatory determination; current (1996), regulatory status of fossil fuel combustion wastes; co-management study; Electric Power Research Institute (EPRI) activities; EPRI coal ash field study sites; oil ash total combustion; fossil fuel combustion; current EPA activities; and Federal Register Notice.

The Space High Angular Resolution Probe for the Infrared (SHARP-IR)

NASA Technical Reports Server (NTRS)

Rinehart, S. A.; Rizzo, M. J.; Leisawitz, D. T.; Staguhn, J. G.; Dipirro, M.; Mentzell, J. E.; Juanola-Parramon, R.; Dhabal, A.; Mundy, L. G.; Moseley, S. H.;

Writing in the Secondary-Level Disciplines: A Systematic Review of Context, Cognition, and Content

ERIC Educational Resources Information Center

Miller, Diane M.; Scott, Chyllis E.; McTigue, Erin M.

2018-01-01

Situated within the historical and current state of writing and adolescent literacy research, this systematic literature review screened 3504 articles to determine the prevalent themes in current research on writing tasks in content-area classrooms. Each of the 3504 studies was evaluated and coded using seven methodological quality indicators. The…

Pre-Service Science Teachers' Perception of the Principles of Scientific Research

ERIC Educational Resources Information Center

Can, Sendil; Kaymakci, Güliz

2016-01-01

The purpose of the current study employing the survey method is to determine the pre-service science teachers' perceptions of the principles of scientific research and to investigate the effects of gender, grade level and the state of following scientific publications on their perceptions. The sampling of the current research is comprised of 125…

Survey of Current Academic Practices for Full-Time Postlicensure Nursing Faculty Who Teach Online

ERIC Educational Resources Information Center

Hanford, Karen J.

2010-01-01

Purpose: The purpose of this study was to determine current academic practices of compensation, workload, rewards, and tenure and promotion for nursing faculty who teach graduate and postlicensure programs that are delivered 50% to 100% online. Deans and directors who are members of the American Association of Colleges of Nursing (AACN) were the…

Study of surge current effects on solid tantalum capacitors

NASA Technical Reports Server (NTRS)

1980-01-01

Results are presented of a 2,000 hour cycled life test program conducted to determine the effect of short term surge current screening on approximately 47 micron f/volt solid tantalum capacitors. The format provides average values and standard deviations of the parameters, capacitance, dissipation factor, and equivalent series resistance at 120 Hz, 1KHz, abd 40 KHz.

Effect of Edge-Preserving Adaptive Image Filter on Low-Contrast Detectability in CT Systems: Application of ROC Analysis

PubMed Central

Okumura, Miwa; Ota, Takamasa; Kainuma, Kazuhisa; Sayre, James W.; McNitt-Gray, Michael; Katada, Kazuhiro

2008-01-01

Objective. For the multislice CT (MSCT) systems with a larger number of detector rows, it is essential to employ dose-reduction techniques. As reported in previous studies, edge-preserving adaptive image filters, which selectively eliminate only the noise elements that are increased when the radiation dose is reduced without affecting the sharpness of images, have been developed. In the present study, we employed receiver operating characteristic (ROC) analysis to assess the effects of the quantum denoising system (QDS), which is an edge-preserving adaptive filter that we have developed, on low-contrast resolution, and to evaluate to what degree the radiation dose can be reduced while maintaining acceptable low-contrast resolution. Materials and Methods. The low-contrast phantoms (Catphan 412) were scanned at various tube current settings, and ROC analysis was then performed for the groups of images obtained with/without the use of QDS at each tube current to determine whether or not a target could be identified. The tube current settings for which the area under the ROC curve (Az value) was approximately 0.7 were determined for both groups of images with/without the use of QDS. Then, the radiation dose reduction ratio when QDS was used was calculated by converting the determined tube current to the radiation dose. Results. The use of the QDS edge-preserving adaptive image filter allowed the radiation dose to be reduced by up to 38%. Conclusion. The QDS was found to be useful for reducing the radiation dose without affecting the low-contrast resolution in MSCT studies. PMID:19043565

Trends and determinants of discretionary salt use: National Health and Nutrition Examination Survey, 2003-2012

USDA-ARS?s Scientific Manuscript database

The objective of this study was to examine the recent temporal trends and current determinants of discretionary salt use in the United States. We used data from the National Health and Nutrition Examination Survey (NHANES), 2003-2012. We used multiple logistic regression to assess temporal trends ...

Immigrant Adolescents Investing in Korean Heritage Language: Exploring Motivation, Identities, and Capital

ERIC Educational Resources Information Center

Kim, Jung-In

2017-01-01

The current study examined the perspectives of seven immigrant adolescents on aspects of their lives that informed their determined and autonomous motivations to learn Korean as a heritage language (HL) in the United States. Constant comparative analyses of interview data showed that, although all of the students experienced determined motivations…

Adapting the Media and Technology Usage and Attitudes Scale to Turkish

ERIC Educational Resources Information Center

Özgür, Hasan

2016-01-01

Due to the requirement of a current, valid, and reliable assessment instrument for determining usage frequencies of technology-based media and the attitudes towards these, this study intends to determine the validity and reliability of the Media and Technology Usage and Attitudes Scale, developed by researchers from California State University,…

Corporatized Higher Education: A Quantitative Study Examining Faculty Motivation Using Self-Determination Theory

ERIC Educational Resources Information Center

Brown, Aaron D.

2016-01-01

The intent of this research is to offer a quantitative analysis of self-determined faculty motivation within the current corporate model of higher education across public and private research universities. With such a heightened integration of accountability structures, external reward systems, and the ongoing drive for more money and…

Self-Monitoring Interventions for Students with Behavior Problems: A Systematic Review of Current Research

ERIC Educational Resources Information Center

Bruhn, Allison; McDaniel, Sara; Kreigh, Christi

2015-01-01

Explicitly teaching skills associated with self-determination has been promoted to support students' independence and control over their own lives. This is especially important for students with behavior problems. One self-determination skill or behavior that has been studied widely is self-monitoring. Although multiple reviews of various…

Defining and Quantifying Potentially Discriminatory Questions in Employment Interviewing.

ERIC Educational Resources Information Center

Springston, Jeffery K.; Keyton, Joann

A study determined what constitutes an illegal pre-employment question, reviewed current laws and literature on the subject, and determined the prevalence of illegal questions asked by organizations. Except in the case of specific statutory law, there is no precise way to define what constitutes an illegal question; however, state and federal…

Determining BMI cut points based on excess percent body fat in US children and adolescents

USDA-ARS?s Scientific Manuscript database

Current cut points for overweight were derived statistically from BMI distribution. The study aimed at determining age-, gender-, and ethnic-specific BMI cut points based on excess body fat in US children and adolescents aged 8-17 years, who participated in the National Health and Nutrition Examinat...

Alternative to Proctoring in Introductory Statistics Community College Courses

ERIC Educational Resources Information Center

Feinman, Yalena

2018-01-01

The credibility of unsupervised exams, one of the biggest challenges of e-learning, is currently maintained by proctoring. However, little has been done to determine whether expensive and inconvenient proctoring is necessary. The purpose of this quantitative study was to determine whether the use of security mechanisms, based on the taxonomy of…

Genetic Determinism in School Textbooks: A Comparative Study Conducted among Sixteen Countries

ERIC Educational Resources Information Center

Castera, Jeremy; Clement, Pierre; Abrougui, Mondher; Nisiforou, Olympia; Valanides, Nicos; Turcinaviciene, Jurga; Sarapuu, Tago; Agorram, Boujemaa; Calado, Florbela; Bogner, Franz; Carvalho, Graca

2008-01-01

Genetic concepts have significantly evolved over the last ten years, and are now less connected to innate ideas and reductionism. Unique reference to genetic determinism has been replaced by the interaction between the genes and their environment (epigenetics). Our analyses relate to how current school biology textbooks present this new paradigm…

Differential pulse voltammetric determination of acyclovir in pharmaceutical preparations using a pencil graphite electrode.

PubMed

Dilgin, Didem Giray; Karakaya, Serkan

2016-06-01

In this study, a new selective and sensitive voltammetric procedure for determination of acyclovir (ACV) was proposed using a disposable electrode, pencil graphite electrode (PGE). Cyclic and differential pulse voltammograms of ACV were recorded in Britton-Robinson buffer solution containing 0.10 M KCl with pH of 4.0 at PGE. The PGE displayed a very good electrochemical behavior with significant enhancement of the peak current compared to a glassy carbon electrode (GCE). Under experimental conditions, the PGE had a linear response range from 1.0 μM to 100.0 μM ACV with a detection limit of 0.3 μM (based on 3 Sb). Relative standard deviations of 4.8 and 3.6% were obtained for five successive determinations of 10.0 and 50.0 μM ACV, respectively, which indicate acceptable repeatability. This voltammetric method was successfully applied to the direct determination of ACV in real pharmaceutical samples. The effect of various interfering compounds on the ACV peak current was studied. Copyright © 2016 Elsevier B.V. All rights reserved.

Determining the Impact of Steady-State PV Fault Current Injections on Distribution Protection

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

Seuss, John; Reno, Matthew J.; Broderick, Robert Joseph

This report investigates the fault current contribution from a single large PV system and the impact it has on existing distribution overcurrent protection devices. Assumptions are made about the modeling of the PV system under fault to perform exhaustive steady - state fault analyses throughout distribution feeder models. Each PV interconnection location is tested to determine how the size of the PV system affects the fault current measured by each protection device. This data is then searched for logical conditions that indicate whether a protection device has operated in a manner that will cause more customer outages due to themore » addition of the PV system. This is referred to as a protection issue , and there are four unique types of issues that have been identified in the study. The PV system size at which any issues occur are recorded to determine the feeder's PV hosting capacity limitations due to interference with protection settings. The analysis is carried out on six feeder models. The report concludes with a discussion of the prevalence and cause of each protection issue caused by PV system fault current.« less

Fractional Factorial Design Study on the Performance of GAC-Enhanced Electrocoagulation Process Involved in Color Removal from Dye Solutions.

PubMed

Secula, Marius Sebastian; Cretescu, Igor; Cagnon, Benoit; Manea, Liliana Rozemarie; Stan, Corneliu Sergiu; Breaban, Iuliana Gabriela

2013-07-10

The aim of this study was to determine the effects of main factors and interactions on the color removal performance from dye solutions using the electrocoagulation process enhanced by adsorption on Granular Activated Carbon (GAC). In this study, a mathematical approach was conducted using a two-level fractional factorial design ( FFD ) for a given dye solution. Three textile dyes: Acid Blue 74, Basic Red 1, and Reactive Black 5 were used. Experimental factors used and their respective levels were: current density (2.73 or 27.32 A/m²), initial pH of aqueous dye solution (3 or 9), electrocoagulation time (20 or 180 min), GAC dose (0.1 or 0.5 g/L), support electrolyte (2 or 50 mM), initial dye concentration (0.05 or 0.25 g/L) and current type (Direct Current- DC or Alternative Pulsed Current- APC ). GAC-enhanced electrocoagulation performance was analyzed statistically in terms of removal efficiency, electrical energy, and electrode material consumptions, using modeling polynomial equations. The statistical significance of GAC dose level on the performance of GAC enhanced electrocoagulation and the experimental conditions that favor the process operation of electrocoagulation in APC regime were determined. The local optimal experimental conditions were established using a multi-objective desirability function method.

Critical current studies of a HTS rectangular coil

NASA Astrophysics Data System (ADS)

Zhong, Z.; Chudy, M.; Ruiz, H. S.; Zhang, X.; Coombs, T.

2017-05-01

Nowadays, superconducting high field magnets are used in numerous applications due to their superior properties. High temperature superconductors (HTS) are usually used for production of circular pancake or racetrack coils. However different geometries of HTS coils might be required for some specific applications. In this study, the HTS coil wound on a rectangular frame was fully characterized in homogeneous DC background field. The study contains measurements of critical current angular dependencies. The critical current of the entire coil and two selected strands under different magnitudes and orientations of external magnetic fields are measured. The critical regions of the coil in different angular regimes are determined. This study brings better understanding of the in- field performance of HTS coils wound on frames with right-angles.

Social Determinants of Smoking in Low- and Middle-Income Countries: Results from the World Health Survey

PubMed Central

Hosseinpoor, Ahmad Reza; Parker, Lucy Anne; Tursan d'Espaignet, Edouard; Chatterji, Somnath

2011-01-01

Introduction Tobacco smoking is a leading cause of premature death and disability, and over 80% of the world's smokers live in low- or middle-income countries. The objective of this study is to assess demographic and socioeconomic determinants of current smoking in low- and middle-income countries. Methods We used data, from the World Health Survey in 48 low-income and middle-income countries, to explore the impact of demographic and socioeconomic factors on the current smoking status of respondents. The data from these surveys provided information on 213,807 respondents aged 18 years or above that were divided into 4 pooled datasets according to their sex and country income group. The overall proportion of current smokers, as well as the proportion by each relevant demographic and socioeconomic determinant, was calculated within each of the pooled datasets, and multivariable logistic regression was used to assess the association between current smoking and these determinants. Results The odds of smoking were not equal in all demographic or socioeconomic groups. Some factors were fairly stable across the four datasets studied: for example, individuals were more likely to smoke if they had little or no education, regardless of if they were male or female, or lived in a low or a middle income country. Nevertheless, other factors, notably age and wealth, showed a differential effect on smoking by sex or country income level. While women in the low-income country group were twice as likely to smoke if they were in the lowest wealth quintile compared with the highest, the association was absent in the middle-income country group. Conclusion Information on how smoking is distributed among low- or middle-income countries will allow policy makers to tailor future policies, and target the most vulnerable populations. PMID:21655299

Social determinants of smoking in low- and middle-income countries: results from the World Health Survey.

PubMed

Hosseinpoor, Ahmad Reza; Parker, Lucy Anne; Tursan d'Espaignet, Edouard; Chatterji, Somnath

2011-01-01

Tobacco smoking is a leading cause of premature death and disability, and over 80% of the world's smokers live in low- or middle-income countries. The objective of this study is to assess demographic and socioeconomic determinants of current smoking in low- and middle-income countries. We used data, from the World Health Survey in 48 low-income and middle-income countries, to explore the impact of demographic and socioeconomic factors on the current smoking status of respondents. The data from these surveys provided information on 213,807 respondents aged 18 years or above that were divided into 4 pooled datasets according to their sex and country income group. The overall proportion of current smokers, as well as the proportion by each relevant demographic and socioeconomic determinant, was calculated within each of the pooled datasets, and multivariable logistic regression was used to assess the association between current smoking and these determinants. The odds of smoking were not equal in all demographic or socioeconomic groups. Some factors were fairly stable across the four datasets studied: for example, individuals were more likely to smoke if they had little or no education, regardless of if they were male or female, or lived in a low or a middle income country. Nevertheless, other factors, notably age and wealth, showed a differential effect on smoking by sex or country income level. While women in the low-income country group were twice as likely to smoke if they were in the lowest wealth quintile compared with the highest, the association was absent in the middle-income country group. Information on how smoking is distributed among low- or middle-income countries will allow policy makers to tailor future policies, and target the most vulnerable populations.

Use of short-term toxicity data for prediction of long-term health effects

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

Hartley, W.R.; Ohanian, E.V.

1988-01-01

Under the Safe Drinking Water Act Amendments of 1986, the US Environmental Protection Agency determines Maximum Contaminant Level Goals (MCLGs) and enforceable Maximum Contaminant Levels (MCLs) or provides lifetime health advisories (HAs) in the absence of regulatory standards. The critical value for calculation of the lifetime level is the reference dose (RfD). The RfD is an estimate of a lifetime dose which is likely to be without significant risk to human populations. The RfD is determined by dividing the no-observed-adverse-effect level (NOAEL) or the lowest-observed-adverse-effect level (LOAEL) by an uncertainty factor (UF). The NOAEL or LOAEL is determined from toxicologicalmore » or epidemiological studies. For many chemicals, human toxicological or epidemiological data are not available. Chronic mammalian studies are sometimes unavailable. Faced with the need for providing guidance for the increasing number of chemicals threatening our drinking water sources, this paper considers the possibility of providing provisional RfDs using data from toxicological studies of less than ninety days duration. The current UF approach is reviewed along with some proposed mathematical models for extrapolation of NOAELs from dose-response data. The current UF approach to developing the RfD is protective and conservative. More research is needed on the relationship of short- and long-term toxicity data to improve our current approach.« less

Transmission electron diffraction determination of the Ge(001)-(2 × 1) surface structure

NASA Astrophysics Data System (ADS)

Collazo-Davila, C.; Grozea, D.; Landree, E.; Marks, L. D.

1997-04-01

The lateral displacements in the Ge(001)-(2 × 1) surface reconstruction have been determined using transmission electron diffraction (TED). The best-fit model includes displacements extending six layers into the bulk. The atomic positions found agree with X-ray studies to within a few hundredths of an ångström. With the positions determined so precisely, it is suggested that the Ge(001)-(2 × 1) surface can now serve as a standard for comparison with theoretical surface structure calculations. The results from the currently available theoretical studies on the surface are compared with the experimentally determined structure.

Magnetospheric electric fields and currents

NASA Technical Reports Server (NTRS)

Mauk, B. H.; Zanetti, L. J.

1987-01-01

The progress made in the years 1983-1986 in understanding the character and operation of magnetospheric electric fields and electric currents is discussed, with emphasis placed on the connection with the interior regions. Special attention is given to determinations of global electric-field configurations, measurements of the response of magnetospheric particle populations to the electric-field configurations, and observations of the magnetospheric currents at high altitude and during northward IMF. Global simulations of current distributions are discussed, and the sources of global electric fields and currents are examined. The topics discussed in the area of impulsive and small-scale phenomena include substorm current systems, impulsive electric fields and associated currents, and field-aligned electrodynamics. A key finding of these studies is that the electric fields and currents are interrelated and cannot be viewed as separate entities.

Wess-Zumino current and the structure of the decay tau- -->K- pi- K+ nu tau.

PubMed

Coan, T E; Gao, Y S; Liu, F; Stroynowski, R; Artuso, M; Boulahouache, C; Blusk, S; Butt, J; Dambasuren, E; Dorjkhaidav, O; Haynes, J; Menaa, N; Mountain, R; Muramatsu, H; Nandakumar, R; Redjimi, R; Sia, R; Skwarnicki, T; Stone, S; Wang, J C; Zhang, Kevin; Mahmood, A H; Csorna, S E; Bonvicini, G; Cinabro, D; Dubrovin, M; Bornheim, A; Lipeles, E; Pappas, S P; Shapiro, A; Weinstein, A J; Briere, R A; Chen, G P; Ferguson, T; Tatishvili, G; Vogel, H; Watkins, M E; Adam, N E; Alexander, J P; Berkelman, K; Boisvert, V; Cassel, D G; Duboscq, J E; Ecklund, K M; Ehrlich, R; Galik, R S; Gibbons, L; Gittelman, B; Gray, S W; Hartill, D L; Heltsley, B K; Hsu, L; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Magerkurth, A; Mahlke-Krüger, H; Meyer, T O; Patterson, J R; Pedlar, T K; Peterson, D; Pivarski, J; Riley, D; Sadoff, A J; Schwarthoff, H; Shepherd, M R; Sun, W M; Thayer, J G; Urner, D; Wilksen, T; Weinberger, M; Athar, S B; Avery, P; Breva-Newell, L; Potlia, V; Stoeck, H; Yelton, J; Eisenstein, B I; Gollin, G D; Karliner, I; Lowrey, N; Naik, P; Sedlack, C; Selen, M; Thaler, J J; Williams, J; Edwards, K W; Besson, D; Gao, K Y; Gong, D T; Kubota, Y; Li, S Z; Poling, R; Scott, A W; Smith, A; Stepaniak, C J; Urheim, J; Metreveli, Z; Seth, K K; Tomaradze, A; Zweber, P; Arms, K; Eckhart, E; Gan, K K; Gwon, C; Severini, H; Skubic, P; Asner, D M; Dytman, S A; Mehrabyan, S; Mueller, J A; Nam, S; Savinov, V; Huang, G S; Miller, D H; Pavlunin, V; Sanghi, B; Shibata, E I; Shipsey, I P J; Adams, G S; Chasse, M; Cummings, J P; Danko, I; Napolitano, J; Cronin-Hennessy, D; Park, C S; Park, W; Thayer, J B; Thorndike, E H

2004-06-11

We present the first study of the vector (Wess-Zumino) current in tau(-)-->K-pi-K+nu(tau) decay using data collected with the CLEO III detector at the Cornell Electron Storage Ring. We determine the quantitative contributions to the decay width from the vector and axial vector currents. Within the framework of a model by Kühn and Mirkes, we identify the quantitative contributions to the total decay rate from the intermediate states omegapi, rho(')pi, and K*K.

Current Options for Determining Fracture Union

PubMed Central

2014-01-01

Determining whether a bone fracture is healed is one of the most important and fundamental clinical determinations made in orthopaedics. However, there are currently no standardized methods of assessing fracture union, which in turn has created significant disagreement among orthopaedic surgeons in both clinical and research settings. An extensive amount of research has been dedicated to finding novel and reliable ways of determining healing with some promising results. Recent advancements in imaging techniques and introduction of new radiographic scores have helped decrease the amount of disagreement on this topic among physicians. The knowledge gained from biomechanical studies of bone healing has helped us refine our tools and create more efficient and practical research instruments. Additionally, a deeper understanding of the molecular pathways involved in the bone healing process has led to emergence of serologic markers as possible candidates in assessment of fracture union. In addition to our current physician centered methods, patient-centered approaches assessing quality of life and function are gaining popularity in assessment of fracture union. Despite these advances, assessment of union remains an imperfect practice in the clinical setting. Therefore, clinicians need to draw on multiple modalities that directly and indirectly measure or correlate with bone healing when counseling patients. PMID:26556422

Determination of Vanadium, Tin and Mercury in Atmospheric Particulate Matter and Cement Dust Samples by Direct Current Plasma Atomic Emission Spectrometry.

ERIC Educational Resources Information Center

Hindy, Kamal T.; And Others

1992-01-01

An atmospheric pollution study applies direct current plasma atomic emission spectrometry (DCP-AES) to samples of total suspended particulate matter collected in two industrial areas and one residential area, and cement dust collected near major cement factories. These samples were analyzed for vanadium, tin, and mercury. The results indicate the…

Effects of Collaborative Consultative Services for Students Who Are Deaf and Hard of Hearing

ERIC Educational Resources Information Center

Kiske, Katie

2017-01-01

The purpose of this research was to determine the perception of consultative services as well as the self-efficacy of both teachers of the deaf and general education teachers that work with students who are D/HH. This study investigated current perceptions and attitudes as well as identified trends in current consultative practice between teachers…

Current State of Inclusion of Children with Special Needs in Child Care Programmes in One Canadian Province

ERIC Educational Resources Information Center

Wiart, Lesley; Kehler, Heather; Rempel, Gwen; Tough, Suzanne

2014-01-01

Background: Access to quality child care is an important support for families with children with disabilities. The objectives of this study were to determine: (1) the current state of inclusion of children with special needs in child care programmes, and (2) the presence of child care staff practices and programme characteristics that support…

Identification of the Competencies, Knowledge, and Skills Needed by School Nutrition Assistants in the Current Environment

ERIC Educational Resources Information Center

Nettles, Mary Frances; Carr, Deborah H.; Cater, Jerry B.; Federico, Holly A.

2009-01-01

Purpose/Objectives: Study objectives were to identify the functional areas, competencies, knowledge, and skills needed by effective school nutrition (SN) assistants in the current SN environment, and determine at what point the SN assistant should be able to know/perform the knowledge/skill statement, at time of hire or after training. Methods: In…

A Current Analysis of the Treatment of Japanese Americans and Internment in United States History Textbooks

ERIC Educational Resources Information Center

Hawkins, Jeffrey M.; Buckendorf, Michael

2010-01-01

A content analysis of ten United States history textbooks (2005-2008) was conducted by the researchers to determine the current depiction of Japanese Americans and internment during the World War II era. This study updates and expands upon the textbooks used in prior research by Romanowski (1995), Harada (2000), and Ogawa (2004) that had numerous…

Wavelet Analysis of Nonstationary Fluctuations of Monte Carlo-Simulated Excitatory Postsynaptic Currents

PubMed Central

Aristizabal, F.; Glavinovic, M. I.

2003-01-01

Tracking spectral changes of rapidly varying signals is a demanding task. In this study, we explore on Monte Carlo-simulated glutamate-activated AMPA patch and synaptic currents whether a wavelet analysis offers such a possibility. Unlike Fourier methods that determine only the frequency content of a signal, the wavelet analysis determines both the frequency and the time. This is owing to the nature of the basis functions, which are infinite for Fourier transforms (sines and cosines are infinite), but are finite for wavelet analysis (wavelets are localized waves). In agreement with previous reports, the frequency of the stationary patch current fluctuations is higher for larger currents, whereas the mean-variance plots are parabolic. The spectra of the current fluctuations and mean-variance plots are close to the theoretically predicted values. The median frequency of the synaptic and nonstationary patch currents is, however, time dependent, though at the peak of synaptic currents, the median frequency is insensitive to the number of glutamate molecules released. Such time dependence demonstrates that the “composite spectra” of the current fluctuations gathered over the whole duration of synaptic currents cannot be used to assess the mean open time or effective mean open time of AMPA channels. The current (patch or synaptic) versus median frequency plots show hysteresis. The median frequency is thus not a simple reflection of the overall receptor saturation levels and is greater during the rise phase for the same saturation level. The hysteresis is due to the higher occupancy of the doubly bound state during the rise phase and not due to the spatial spread of the saturation disk, which remains remarkably constant. Albeit time dependent, the variance of the synaptic and nonstationary patch currents can be accurately determined. Nevertheless the evaluation of the number of AMPA channels and their single current from the mean-variance plots of patch or synaptic currents is not highly accurate owing to the varying number of the activatable AMPA channels caused by desensitization. The spatial nonuniformity of open, bound, and desensitized AMPA channels, and the time dependence and spatial nonuniformity of the glutamate concentration in the synaptic cleft, further reduce the accuracy of estimates of the number of AMPA channels from synaptic currents. In conclusion, wavelet analysis of nonstationary fluctuations of patch and synaptic currents expands our ability to determine accurately the variance and frequency of current fluctuations, demonstrates the limits of applicability of techniques currently used to evaluate the single channel current and number of AMPA channels, and offers new insights into the mechanisms involved in the generation of unitary quantal events at excitatory central synapses. PMID:14507683

Wavelet analysis of nonstationary fluctuations of Monte Carlo-simulated excitatory postsynaptic currents.

PubMed

Aristizabal, F; Glavinovic, M I

2003-10-01

Tracking spectral changes of rapidly varying signals is a demanding task. In this study, we explore on Monte Carlo-simulated glutamate-activated AMPA patch and synaptic currents whether a wavelet analysis offers such a possibility. Unlike Fourier methods that determine only the frequency content of a signal, the wavelet analysis determines both the frequency and the time. This is owing to the nature of the basis functions, which are infinite for Fourier transforms (sines and cosines are infinite), but are finite for wavelet analysis (wavelets are localized waves). In agreement with previous reports, the frequency of the stationary patch current fluctuations is higher for larger currents, whereas the mean-variance plots are parabolic. The spectra of the current fluctuations and mean-variance plots are close to the theoretically predicted values. The median frequency of the synaptic and nonstationary patch currents is, however, time dependent, though at the peak of synaptic currents, the median frequency is insensitive to the number of glutamate molecules released. Such time dependence demonstrates that the "composite spectra" of the current fluctuations gathered over the whole duration of synaptic currents cannot be used to assess the mean open time or effective mean open time of AMPA channels. The current (patch or synaptic) versus median frequency plots show hysteresis. The median frequency is thus not a simple reflection of the overall receptor saturation levels and is greater during the rise phase for the same saturation level. The hysteresis is due to the higher occupancy of the doubly bound state during the rise phase and not due to the spatial spread of the saturation disk, which remains remarkably constant. Albeit time dependent, the variance of the synaptic and nonstationary patch currents can be accurately determined. Nevertheless the evaluation of the number of AMPA channels and their single current from the mean-variance plots of patch or synaptic currents is not highly accurate owing to the varying number of the activatable AMPA channels caused by desensitization. The spatial nonuniformity of open, bound, and desensitized AMPA channels, and the time dependence and spatial nonuniformity of the glutamate concentration in the synaptic cleft, further reduce the accuracy of estimates of the number of AMPA channels from synaptic currents. In conclusion, wavelet analysis of nonstationary fluctuations of patch and synaptic currents expands our ability to determine accurately the variance and frequency of current fluctuations, demonstrates the limits of applicability of techniques currently used to evaluate the single channel current and number of AMPA channels, and offers new insights into the mechanisms involved in the generation of unitary quantal events at excitatory central synapses.

System and method to determine electric motor efficiency nonintrusively

DOEpatents

Lu, Bin [Kenosha, WI; Habetler, Thomas G [Snellville, GA; Harley, Ronald G [Lawrenceville, GA

2011-08-30

A system and method for nonintrusively determining electric motor efficiency includes a processor programed to, while the motor is in operation, determine a plurality of stator input currents, electrical input data, a rotor speed, a value of stator resistance, and an efficiency of the motor based on the determined rotor speed, the value of stator resistance, the plurality of stator input currents, and the electrical input data. The determination of the rotor speed is based on one of the input power and the plurality of stator input currents. The determination of the value of the stator resistance is based on at least one of a horsepower rating and a combination of the plurality of stator input currents and the electrical input data. The electrical input data includes at least one of an input power and a plurality of stator input voltages.

Research of Steel-dielectric Transition Using Subminiature Eddy-current Transducer

NASA Astrophysics Data System (ADS)

Dmitriev, S. F.; Malikov, V. N.; Sagalakov, A. M.; Ishkov, A. V.

2018-05-01

The research aims to develop a subminiature transducer for electrical steel investigation. The authors determined the capability to study steel characteristics at different depths based on variations of eddy-current transducer amplitude at the steel-dielectric boundary. A subminiature transformer-type transducer was designed, which enables to perform local investigations of ferromagnetic materials using an eddy-current method based on local studies of the steel electrical conductivity. Having the designed transducer as a basis, a hardware-software complex was built to perform experimental studies of steel at the interface boundary. Test results are reported for a specimen with continuous and discrete measurements taken at different frequencies. The article provides the key technical information about the eddy current transformer used and describes the methodology of measurements that makes it possible to control steel to dielectric transition.

Modelling the effect of electrode displacement on transcranial direct current stimulation (tDCS)

NASA Astrophysics Data System (ADS)

Ramaraju, Sriharsha; Roula, Mohammed A.; McCarthy, Peter W.

2018-02-01

Objective. Transcranial direct current stimulation (tDCS) is a neuromodulatory technique that delivers a low-intensity, direct current to cortical areas with the purpose of modulating underlying brain activity. Recent studies have reported inconsistencies in tDCS outcomes. The underlying assumption of many tDCS studies has been that replication of electrode montage equates to replicating stimulation conditions. It is possible however that anatomical difference between subjects, as well as inherent inaccuracies in montage placement, could affect current flow to targeted areas. The hypothesis that stimulation of a defined brain region will be stable under small displacements was tested. Approach. Initially, we compared the total simulated current flowing through ten specific brain areas for four commonly used tDCS montages: F3-Fp2, C3-Fp2, Fp1-F4, and P3-P4 using the software tool COMETS. The effect of a slight (~1 cm in each of four directions) anode displacement on the simulated regional current density for each of the four tDCS montages was then determined. Current flow was calculated and compared through ten segmented brain areas to determine the effect of montage type and displacement. The regional currents, as well as the localised current densities, were compared with the original electrode location, for each of these new positions. Main results. Recommendations for montages that maximise stimulation current for the ten brain regions are considered. We noted that the extent to which stimulation is affected by electrode displacement varies depending on both area and montage type. The F3-Fp2 montage was found to be the least stable with up to 38% change in average current density in the left frontal lobe while the Fp1-F4 montage was found to the most stable exhibiting only 1% change when electrodes were displaced. Significance. These results indicate that even relatively small changes in stimulation electrode placement appear to result in surprisingly large changes in current densities and distribution.

Recent Simulation Results on Ring Current Dynamics Using the Comprehensive Ring Current Model

NASA Technical Reports Server (NTRS)

Zheng, Yihua; Zaharia, Sorin G.; Lui, Anthony T. Y.; Fok, Mei-Ching

2010-01-01

Plasma sheet conditions and electromagnetic field configurations are both crucial in determining ring current evolution and connection to the ionosphere. In this presentation, we investigate how different conditions of plasma sheet distribution affect ring current properties. Results include comparative studies in 1) varying the radial distance of the plasma sheet boundary; 2) varying local time distribution of the source population; 3) varying the source spectra. Our results show that a source located farther away leads to a stronger ring current than a source that is closer to the Earth. Local time distribution of the source plays an important role in determining both the radial and azimuthal (local time) location of the ring current peak pressure. We found that post-midnight source locations generally lead to a stronger ring current. This finding is in agreement with Lavraud et al.. However, our results do not exhibit any simple dependence of the local time distribution of the peak ring current (within the lower energy range) on the local time distribution of the source, as suggested by Lavraud et al. [2008]. In addition, we will show how different specifications of the magnetic field in the simulation domain affect ring current dynamics in reference to the 20 November 2007 storm, which include initial results on coupling the CRCM with a three-dimensional (3-D) plasma force balance code to achieve self-consistency in the magnetic field.

FBI fingerprint identification automation study: AIDS 3 evaluation report. Volume 5: Current system evaluation

NASA Technical Reports Server (NTRS)

Mulhall, B. D. L.

1980-01-01

The performance, costs, organization and other characteristics of both the manual system and AIDS 2 were used to establish a baseline case. The results of the evaluation are to be used to determine the feasibility of the AIDS 3 System, as well as provide a basis for ranking alternative systems during the second phase of the JPL study. The results of the study were tabulated by subject, scope and methods, providing a descriptive, quantitative and qualitative analysis of the current operating systems employed by the FBI Identification Division.

Social determinants of health and tobacco use in thirteen low and middle income countries: evidence from Global Adult Tobacco Survey.

PubMed

Palipudi, Krishna M; Gupta, Prakash C; Sinha, Dhirendra N; Andes, Linda J; Asma, Samira; McAfee, Tim

2012-01-01

Tobacco use has been identified as the single biggest cause of inequality in morbidity. The objective of this study is to examine the role of social determinants on current tobacco use in thirteen low-and-middle income countries. We used nationally representative data from the Global Adult Tobacco Survey (GATS) conducted during 2008-2010 in 13 low-and-middle income countries: Bangladesh, China, Egypt, India, Mexico, Philippines, Poland, Russian Federation, Thailand, Turkey, Ukraine, Uruguay, and Viet Nam. These surveys provided information on 209,027 respondent's aged 15 years and above and the country datasets were analyzed individually for estimating current tobacco use across various socio-demographic factors (gender, age, place of residence, education, wealth index, and knowledge on harmful effects of smoking). Multiple logistic regression analysis was used to predict the impact of these determinants on current tobacco use status. Current tobacco use was defined as current smoking or use of smokeless tobacco, either daily or occasionally. Former smokers were excluded from the analysis. Adjusted odds ratios for current tobacco use after controlling other cofactors, was significantly higher for males across all countries and for urban areas in eight of the 13 countries. For educational level, the trend was significant in Bangladesh, Egypt, India, Philippines and Thailand demonstrating decreasing prevalence of tobacco use with increasing levels of education. For wealth index, the trend of decreasing prevalence of tobacco use with increasing wealth was significant for Bangladesh, India, Philippines, Thailand, Turkey, Ukraine, Uruguay and Viet Nam. The trend of decreasing prevalence with increasing levels of knowledge on harmful effects of smoking was significant in China, India, Philippines, Poland, Russian Federation, Thailand, Ukraine and Viet Nam. These findings demonstrate a significant but varied role of social determinants on current tobacco use within and across countries.

[Quality of hospital discharge reports in terms of current legislation and expert recommendations].

PubMed

Zambrana-García, José Luis; Rivas-Ruiz, Francisco

2013-01-01

To determine the quality of hospital discharge reports (HDRs) taking into account current legislation and the conclusions of the consensus on hospital discharge reports in medical specialities in 11 community hospitals in Andalusia (Spain). A cross-sectional study of 1,708 HDRs was carried out. We determined the presence or absence of the various items required by current legislation and by the recommendations of the above-mentioned consensus. A total of 97.4% (95% confidence interval [95% CI]: 96.5-98.2) of the HDRs were classified as satisfactory according to the stipulations of current legislation. However, when the assessment was based on the consensus, the rate of adequacy fell to 72.1% (95% CI: 70.0-74.3). A notable finding was the absence of the duration of treatment after hospital discharge in 39.4% of the HDRs. HDRs show an excellent level of compliance with the data required by current regulations, but their intrinsic quality needs to be improved. Copyright © 2012 SESPAS. Published by Elsevier Espana. All rights reserved.

Dendritic Ag-Fe nanocrystalline alloy synthesized by pulsed electrodeposition and its characterization

NASA Astrophysics Data System (ADS)

Santhi, Kalavathy; Revathy, T. A.; Narayanan, V.; Stephen, A.

2014-10-01

Synthesis of dendrite shaped Ag-Fe alloy nanomaterial by pulsed electrodeposition route was investigated. The alloy samples were deposited at different current densities from electrolytes of different compositions to study the influence of current density and bath composition on metal contents in the alloy, which was determined by ICP-OES analysis. The XRD studies were carried out to determine the structure of these samples. Magnetic characterization at room temperature and during heating was carried out to understand their magnetic behaviour and to confirm the inferences drawn from the XRD results. The XPS spectra proved the presence of Fe and Ag in the metallic form in the alloy samples. The FESEM and TEM micrographs were taken to view the surface morphology of the nanosized particles.

Measuring Zonal Transport Variability of the Antarctic Circumpolar Current Using GRACE Ocean Bottom Pressure

NASA Astrophysics Data System (ADS)

Makowski, J.; Chambers, D. P.; Bonin, J. A.

2012-12-01

Previous studies have suggested that ocean bottom pressure (OBP) can be used to measure the transport variability of the Antarctic Circumpolar Current (ACC). Using OBP data from the JPL ECCO model and the Gravity Recovery and Climate Experiment (GRACE), we examine the zonal transport variability of the ACC integrated between the major fronts between 2003-2010. The JPL ECCO data are used to determine average front positions for the time period studies, as well as where transport is mainly zonal. Statistical analysis will be conducted to determine the uncertainty of the GRACE observations using a simulated data set. We will also begin looking at low frequency changes and how coherent transport variability is from region to region of the ACC. Correlations with bottom pressure south of the ACC and the average basin transports will also be calculated to determine the probability of using bottom pressure south of the ACC as a means for describing the ACC dynamics and transport.

Research and Evaluations of the Health Aspects of Disasters, Part VII: The Relief/Recovery Framework.

PubMed

Birnbaum, Marvin L; Daily, Elaine K; O'Rourke, Ann P

2016-04-01

The principal goal of research relative to disasters is to decrease the risk that a hazard will result in a disaster. Disaster studies pursue two distinct directions: (1) epidemiological (non-interventional); and (2) interventional. Both interventional and non-interventional studies require data/information obtained from assessments of function. Non-interventional studies examine the epidemiology of disasters. Interventional studies evaluate specific interventions/responses in terms of their effectiveness in meeting their respective objectives, their contribution to the overarching goal, other effects created, their respective costs, and the efficiency with which they achieved their objectives. The results of interventional studies should contribute to evidence that will be used to inform the decisions used to define standards of care and best practices for a given setting based on these standards. Interventional studies are based on the Disaster Logic Model (DLM) and are used to change or maintain levels of function (LOFs). Relief and Recovery interventional studies seek to determine the effects, outcomes, impacts, costs, and value of the intervention provided after the onset of a damaging event. The Relief/Recovery Framework provides the structure needed to systematically study the processes involved in providing relief or recovery interventions that result in a new LOF for a given Societal System and/or its component functions. It consists of the following transformational processes (steps): (1) identification of the functional state prior to the onset of the event (pre-event); (2) assessments of the current functional state; (3) comparison of the current functional state with the pre-event state and with the results of the last assessment; (4) needs identification; (5) strategic planning, including establishing the overall strategic goal(s), objectives, and priorities for interventions; (6) identification of options for interventions; (7) selection of the most appropriate intervention(s); (8) operational planning; (9) implementation of the intervention(s); (10) assessments of the effects and changes in LOFs resulting from the intervention(s); (11) determination of the costs of providing the intervention; (12) determination of the current functional status; (13) synthesis of the findings with current evidence to define the benefits and value of the intervention to the affected population; and (14) codification of the findings into new evidence. Each of these steps in the Framework is a production function that facilitates evaluation, and the outputs of the transformation process establish the current state for the next step in the process. The evidence obtained is integrated into augmenting the respective Response Capacities of a community-at-risk. The ultimate impact of enhanced Response Capacity is determined by studying the epidemiology of the next event.

Factors Contributing to Regular Smoking in Adolescents in Turkey

ERIC Educational Resources Information Center

Can, Gamze; Topbas, Murat; Oztuna, Funda; Ozgun, Sukru; Can, Emine; Yavuzyilmaz, Asuman

2009-01-01

Purpose: The objectives of this study were to determine the levels of lifetime cigarette use, daily use, and current use among young people (aged 15-19 years) and to examine the risk factors contributing to regular smoking. Methods: The number of students was determined proportionately to the numbers of students in all the high schools in the…

Paternal B vitamin intake is a determinant of growth, hepatic lipid metabolism and intestinal tumor volume in female Apc1638N mouse offspring

USDA-ARS?s Scientific Manuscript database

Background: The importance of maternal nutrition to offspring health and risk of disease is well established. Emerging evidence suggests paternal diet may affect offspring health as well. Objective: In the current study we sought to determine whether modulating pre-conception paternal B vitamin inta...

Parental Influences on the Academic Motivation of Gifted Students: A Self-Determination Theory Perspective

ERIC Educational Resources Information Center

Garn, Alex C.; Matthews, Michael S.; Jolly, Jennifer L.

2010-01-01

The home environment that parents provide their gifted children can have a significant impact on academic motivation, yet limited research has focused on this topic. Self-determination theory, a comprehensive framework of motivation, was used in the current study to explore two research questions: (a) What attitudes do parents of gifted students…

Determination of sugars in honey by liquid chromatography

PubMed Central

Kamal, Mohammad A.; Klein, Peter

2010-01-01

Honey is a rich conventional natural resource of sweetness and energy for human beings. A protocol for the determination of two important monosaccharide sugars (fructose and glucose) in honey was established in the current study by using normal phase partition liquid chromatography and 1–5% combined working standard of glucose, fructose and sucrose. PMID:23961099

Reliability of Near-Infrared Spectroscopy for Determining Muscle Oxygen Saturation during Exercise

ERIC Educational Resources Information Center

Austin, Krista G.; Daigle, Karen A.; Patterson, Patricia; Cowman, Jason; Chelland, Sara; Haymes, Emily M.

2005-01-01

Near-infrared spectroscopy is currently used to assess changes in the oxygen saturation of the muscle during exercise. The primary purpose of this study was to assess the reliability of near-infrared spectroscopy in determining muscle oxygen saturation (StO[subscript 2]) in the vastus lateralis during cycling and the gastrocnemius during running…

Examining International Students' Motivation to Read in English from a Self-Determination Theory Perspective

ERIC Educational Resources Information Center

Komiyama, Reiko; McMorris, Alessandra

2017-01-01

Motivation is thought to contribute to better text comprehension (Grabe, 2009), but L2 reading motivation of adult ESL students in the US is an underexplored area of research. The current study adopted self-determination theory--the concepts of intrinsic motivation, identified regulation, and controlled motivation, in particular--to examine IEP…

Cast Stone Formulation for Nuclear Waste Immobilization at Higher Sodium Concentrations

DOE PAGES

Fox, Kevin; Cozzi, Alex; Roberts, Kimberly; ...

2014-11-01

Low activity radioactive waste at U.S. Department of Energy sites can be immobilized for permanent disposal using cementitious waste forms. This study evaluated waste forms produced with simulated wastes at concentrations up to twice that of currently operating processes. The simulated materials were evaluated for their fresh properties, which determine processability, and cured properties, which determine waste form performance. The results show potential for greatly reducing the volume of material. Fresh properties were sufficient to allow for processing via current practices. Cured properties such as compressive strength meet disposal requirements. Leachability indices provide an indication of expected long-term performance.

Mechanisms of Current Transfer in Electrodeposited Layers of Submicron Semiconductor Particles

NASA Astrophysics Data System (ADS)

Zhukov, N. D.; Mosiyash, D. S.; Sinev, I. V.; Khazanov, A. A.; Smirnov, A. V.; Lapshin, I. V.

2017-12-01

Current-voltage ( I- V) characteristics of conductance in multigrain layers of submicron particles of silicon, gallium arsenide, indium arsenide, and indium antimonide have been studied. Nanoparticles of all semiconductors were obtained by processing initial single crystals in a ball mill and applied after sedimentation onto substrates by means of electrodeposition. Detailed analysis of the I- V curves of electrodeposited layers shows that their behavior is determined by the mechanism of intergranular tunneling emission from near-surface electron states of submicron particles. Parameters of this emission process have been determined. The proposed multigrain semiconductor structures can be used in gas sensors, optical detectors, IR imagers, etc.

Tomographic reconstruction of layered tissue structures

NASA Astrophysics Data System (ADS)

Hielscher, Andreas H.; Azeez-Jan, Mohideen; Bartel, Sebastian

2001-11-01

In recent years the interest in the determination of optical properties of layered tissue structure has resurfaced. Applications include, for example, studies on layered skin tissue and underlying muscles, imaging of the brain underneath layers of skin, skull, and meninges, and imaging of the fetal head in utero beneath the layered structures of the maternal abdomen. In this work we approach the problem of layered structures in the framework of model-based iterative image reconstruction schemes. These schemes are currently developed to determine the optical properties inside tissue from measurement on the surface. If applied to layered structure these techniques yield substantial improvements over currently available semi-analytical approaches.

Electric field characteristics of electroconvulsive therapy with individualized current amplitude: a preclinical study.

PubMed

Lee, Won Hee; Lisanby, Sarah H; Laine, Andrew F; Peterchev, Angel V

2013-01-01

This study examines the characteristics of the electric field induced in the brain by electroconvulsive therapy (ECT) with individualized current amplitude. The electric field induced by bilateral (BL), bifrontal (BF), right unilateral (RUL), and frontomedial (FM) ECT electrode configurations was computed in anatomically realistic finite element models of four nonhuman primates (NHPs). We generated maps of the electric field strength relative to an empirical neural activation threshold, and determined the stimulation strength and focality at fixed current amplitude and at individualized current amplitudes corresponding to seizure threshold (ST) measured in the anesthetized NHPs. The results show less variation in brain volume stimulated above threshold with individualized current amplitudes (16-36%) compared to fixed current amplitude (30-62%). Further, the stimulated brain volume at amplitude-titrated ST is substantially lower than that for ECT with conventional fixed current amplitudes. Thus individualizing the ECT stimulus current could compensate for individual anatomical variability and result in more focal and uniform electric field exposure across different subjects compared to the standard clinical practice of using high, fixed current for all patients.

Potential, Current, and Ionic Fluxes across the Isolated Retinal Pigment Epithelium and Choroid

PubMed Central

Lasansky, Arnaldo; de Fisch, Felisa W.

1966-01-01

A flux chamber was utilized for in vitro studies of a membrane formed by the retinal pigment epithelium and choroid of the eye of the toad (Bufo arenarum and Bufo marinus). A transmembrane potential of 20 to 30 mv was found, the pigment epithelium surface positive with respect to the choroidal surface. Unidirectional fluxes of chloride, sodium, potassium, and calcium were determined in the absence of an electrochemical potential difference. A net transfer of chloride from pigment epithelium to choroid accounted for a major fraction of the mean short-circuit current. A small net flux of sodium from choroid to pigment epithelium was detected in Bufo marinus. In both species of toads, however, about one-third of the mean short-circuit current remained unaccounted for. Manometric determinations of bicarbonate suggested an uptake of this ion at the epithelial surface of the membrane but did not provide evidence of a relationship between this process and the short-circuit current. PMID:5961357

Determination of current loads of floating platform for special purposes

NASA Astrophysics Data System (ADS)

Ma, Guang-ying; Yao, Yun-long; Zhao, Chen-yao

2017-08-01

This article studied a new floating offshore platform for special purposes, which was assembled by standard floating modules. The environmental load calculation of the platform is an important part of the research of the ocean platform, which has always been paid attention to by engineers. In addition to wave loads, the wind loads and current loads are also important environmental factors that affect the dynamic response of the offshore platform. The current loads on the bottom structure should not be ignored. By Fluent software, the hydrostatic conditions and external current loads of the platform were calculated in this paper. The coefficient which is independent of the current velocity, namely, current force coefficient, can be fitted through current loads, which can be used for the consequent hydrodynamic and mooring analyses.

Determinants of internal migrant health and the healthy migrant effect in South India: a mixed methods study.

PubMed

Dodd, Warren; Humphries, Sally; Patel, Kirit; Majowicz, Shannon; Little, Matthew; Dewey, Cate

2017-09-12

Internal labour migration is an important and necessary livelihood strategy for millions of individuals and households in India. However, the precarious position of migrant workers within Indian society may have consequences for the health of these individuals. Previous research on the connections between health and labour mobility within India have primarily focused on the negative health outcomes associated with this practice. Thus, there is a need to better identify the determinants of internal migrant health and how these determinants shape migrant health outcomes. An exploratory mixed methods study was conducted in 26 villages in the Krishnagiri district of Tamil Nadu. Sixty-six semi-structured interviews were completed using snowball sampling, followed by 300 household surveys using multi-stage random sampling. For qualitative data, an analysis of themes and content was completed. For quantitative data, information on current participation in internal labour migration, in addition to self-reported morbidity and determinants of internal migrant health, was collected. Morbidity categories were compared between migrant and non-migrant adults (age 14-65 years) using a Fisher's exact test. Of the 300 households surveyed, 137 households (45.7%) had at least one current migrant member, with 205 migrant and 1012 non-migrant adults (age 14-65 years) included in this study. The health profile of migrant and non-migrants was similar in this setting, with 53 migrants (25.9%) currently suffering from a health problem compared to 273 non-migrants (27.0%). Migrant households identified both occupational and livelihood factors that contributed to changes in the health of their migrant members. These determinants of internal migrant health were corroborated and further expanded on through the semi-structured interviews. Internal labour migration in and of itself is not a determinant of health, as participation in labour mobility can contribute to an improvement in health, a decline in health, or no change in health among migrant workers. Targeted public health interventions should focus on addressing the determinants of internal migrant health to enhance the contributions these individuals can make to their households and villages of origin.

Sulfates in Indiana substrates.

DOT National Transportation Integrated Search

2016-06-01

This study was undertaken to develop modifications for improving cost and time efficiencies without sacrificing accuracy and precision to : the current method employed by the Indiana Department of Transportation (INDOT) for determining sulfate conten...

Roadwaste : issues and options.

DOT National Transportation Integrated Search

1998-06-01

The Oregon Department of Transportation (ODOT) is conducting a study to determine roadwaste management options. Phase 1 consisted of a thorough review of regulations and standards, roadwaste characterization, current management practices, and new tec...

United States-Federal Republic of Germany cooperative study of advanced ground vehicle ride quality

DOT National Transportation Integrated Search

1979-11-01

In the first phase of this study, the relative comfort : assoiciated with various speed-guideway configurations for a proposed : magnetically levitated vehicle (Figure 1) and for a currently : operating Bundesbahn rail-coach were determined. The ride...

Permeability and stability of base and subbase materials : appendices A-Q, August 2000.

DOT National Transportation Integrated Search

2000-08-01

This study determined the hydraulic conductivities, effective porosities and resilient moduli of several current and proposed drainable base materials. The materials studied were AASHTO No. 57, AASHTO No. 67, ODOT No. 304, ODOT No. 310, Iowa DOT No. ...

Permeability and stability of base and subbase materials : final report, August 2000.

DOT National Transportation Integrated Search

2000-08-01

This study determined the hydraulic conductivities, effective porosities and resilient moduli of several current and proposed drainable base materials. The materials studied were AASHTO No. 57, AASHTO No. 67, ODOT No. 304, ODOT No. 310, Iowa DOT No. ...

Permeability and stability of base and subbase materials : executive summary, August 2000.

DOT National Transportation Integrated Search

2000-08-01

This study determined the hydraulic conductivities, effective porosities and resilient moduli of several current and proposed drainable base materials. The materials studied were AASHTO No. 57, AASHTO No. 67, ODOT No. 304, ODOT No. 310, Iowa DOT No. ...

Evaluation of Surface Sampling for Bacillus Spores Using ...

EPA Pesticide Factsheets

Journal Article In this study, commercially-available domestic cleaning robots were evaluated for spore surface sampling efficiency on common indoor surfaces. The current study determined the sampling efficiency of each robot, without modifying the sensors, algorithms, or logics set by the manufacturers.

Misinformation contributing to safety issues in vehicle restraints for children : a rural/urban comparison.

DOT National Transportation Integrated Search

2013-12-01

This study sought to determine current knowledge-levels of health care providers regarding child passenger safety issues and frequency of counseling on this topic. In addition, this study explored the differences in child restraint knowledge levels a...

Methods for locating ground faults and insulation degradation condition in energy conversion systems

DOEpatents

Agamy, Mohamed; Elasser, Ahmed; Galbraith, Anthony William; Harfman Todorovic, Maja

2015-08-11

Methods for determining a ground fault or insulation degradation condition within energy conversion systems are described. A method for determining a ground fault within an energy conversion system may include, in part, a comparison of baseline waveform of differential current to a waveform of differential current during operation for a plurality of DC current carrying conductors in an energy conversion system. A method for determining insulation degradation within an energy conversion system may include, in part, a comparison of baseline frequency spectra of differential current to a frequency spectra of differential current transient at start-up for a plurality of DC current carrying conductors in an energy conversion system. In one embodiment, the energy conversion system may be a photovoltaic system.

Wet Scrubber System Study. Volume II. Final Report and Bibliography.

ERIC Educational Resources Information Center

Calvert, Seymour; And Others

This report is the second volume of a two-part study on wet scrubber systems. The study was undertaken to achieve the following objectives: (1) evaluate current engineering technology, (2) evaluate existing scrubber systems, (3) investigate present usage problems, (4) determine potential new applications, and (5) develop specific research…

Average current is better than peak current as therapeutic dosage for biphasic waveforms in a ventricular fibrillation pig model of cardiac arrest.

PubMed

Chen, Bihua; Yu, Tao; Ristagno, Giuseppe; Quan, Weilun; Li, Yongqin

2014-10-01

Defibrillation current has been shown to be a clinically more relevant dosing unit than energy. However, the effects of average and peak current in determining shock outcome are still undetermined. The aim of this study was to investigate the relationship between average current, peak current and defibrillation success when different biphasic waveforms were employed. Ventricular fibrillation (VF) was electrically induced in 22 domestic male pigs. Animals were then randomized to receive defibrillation using one of two different biphasic waveforms. A grouped up-and-down defibrillation threshold-testing protocol was used to maintain the average success rate of 50% in the neighborhood. In 14 animals (Study A), defibrillations were accomplished with either biphasic truncated exponential (BTE) or rectilinear biphasic waveforms. In eight animals (Study B), shocks were delivered using two BTE waveforms that had identical peak current but different waveform durations. Both average and peak currents were associated with defibrillation success when BTE and rectilinear waveforms were investigated. However, when pathway impedance was less than 90Ω for the BTE waveform, bivariate correlation coefficient was 0.36 (p=0.001) for the average current, but only 0.21 (p=0.06) for the peak current in Study A. In Study B, a high defibrillation success (67.9% vs. 38.8%, p<0.001) was observed when the waveform delivered more average current (14.9±2.1A vs. 13.5±1.7A, p<0.001) while keeping the peak current unchanged. In this porcine model of VF, average current was better than peak current to be an adequate parameter to describe the therapeutic dosage when biphasic defibrillation waveforms were used. The institutional protocol number: P0805. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Can ELT in Higher Education Be Successful? The Current Status of ELT in Mexico

ERIC Educational Resources Information Center

Vazquez, Alberto Mora; Guzman, Nelly Paulina Trejo; Roux, Ruth

2013-01-01

The purpose of this paper is to analyze the determinants of the current state of the ELT field in Mexican contexts. In particular, it explores the ways in which diverse social and political factors hamper the successful implementation of national and institutional ELT policies. Drawing on a case study carried out throughout a period of five years,…

Long-range eye tracking: A feasibility study

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

Jayaweera, S.K.; Lu, Shin-yee

1994-08-24

The design considerations for a long-range Purkinje effects based video tracking system using current technology is presented. Past work, current experiments, and future directions are thoroughly discussed, with an emphasis on digital signal processing techniques and obstacles. It has been determined that while a robust, efficient, long-range, and non-invasive eye tracking system will be difficult to develop, such as a project is indeed feasible.

Analysis of Imp-C data from the magnetospheric tail

NASA Technical Reports Server (NTRS)

Speiser, T. W.

1973-01-01

Satellite magnetic field measurements in the geomagnetic tail current sheet are analyzed to determine the normal field component, and other CS parameters such as thickness, motion, vector current density, etc., and to make correlations with auroral activity as measured by the A sub e index. The satellite data used in the initial part of this study were from Explorer 28 and Explorer 34 satellites.

Relationship between Online Learning Readiness and Structure and Interaction of Online Learning Students

ERIC Educational Resources Information Center

Demir Kaymak, Zeliha; Horzum, Mehmet Baris

2013-01-01

Current study tried to determine whether a relationship exists between readiness levels of the online learning students for online learning and the perceived structure and interaction in online learning environments. In the study, cross sectional survey model was used. The study was conducted with 320 voluntary students studying online learning…

Toxicity and bioconcentration of hexachlorocyclohexane (HCH) in an air-breathing catfish, Saccobranchus fossilis (Bloch)

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

Khangarot, B.S.; Takroo, R.; Singh, R.R.

1991-12-01

The current study was undertaken to determine the sublethal toxicity of commercial grade hexachlorocyclohexane (HCH) to a freshwater air-breathing catfish, Saccobranchus fossilis (Bloch) for 14 days. The bioconcentration of HCH and its distribution in gill, brain and liver was determined. This species was selected for the present study because it is widely distributed in ponds, lakes and rivers of India and consumed as human diet in many parts of the world.

76 FR 71934 - Tobacco Transition Payment Program; Availability of Current Assessment Methods Determination...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-21

... DEPARTMENT OF AGRICULTURE Farm Service Agency Tobacco Transition Payment Program; Availability of Current Assessment Methods Determination Document AGENCY: Commodity Credit Corporation and Farm Service... current methods used to calculate manufacturer and importer assessments that fund the Tobacco Transition...

Assessment of Consumer Health Education Needs of DeWitt MEDDAC, Fort Belvoir, Virginia.

DTIC Science & Technology

1975-03-01

current patient education programs; to determine educational methodologies used for current patient education programs; to determine resources, both...technological and personnel, used for current patient education programs; to systematically identify local consumer health education needs from input by

General practitioners' competence and confidentiality determinations with a minor who requests the oral contraceptive pill.

PubMed

Bartholomew, Terence P; Carvalho, Tatiana

2005-11-01

The right of minors to make medical treatment decisions is an issue that is not explicitly addressed in the legislation of most Australian jurisdictions. While recent common law decisions allow competent minors to consent to treatment, current legislation in Victoria does not provide adequate guidelines on how competence is to be measured. It is also unclear whether the duty of confidentiality is extended to competent minors. The current study explored general practitioners' competence and confidentiality decisions with a hypothetical 14-year-old patient who requests the oral contraceptive pill (OCP). Questionnaires were sent to 1,000 Victorian general practitioners, 305 of whom responded. General practitioners were asked to determine whether "Liz" was competent to request the OCP, and whether they would maintain her confidentiality. A total of 81% of respondents found the patient competent, while 91% would have maintained her confidentiality. Results indicate that the majority of general practitioners used rationales that generally did not conform to current legal principles when making competence and confidentiality determinations regarding this patient.

Mid-Atomic-Number Cylindrical Wire Array Precursor Plasma Studies on Zebra

DOE PAGES

Stafford, A; Safronova, A. S.; Kantsyrev, V. L.; ...

2014-12-30

The precursor plasmas from low wire number cylindrical wire arrays (CWAs) were previously shown to radiate at temperatures >300 eV for Ni-60 (94% Cu and 6% Ni) wires in experiments on the 1-MA Zebra generator. Continued research into precursor plasmas has studied additional midatomic-number materials including Cu and Alumel (95% Ni, 2% Al, 2% Mn, and 1% Si) to determine if the >300 eV temperatures are common for midatomic-number materials. Additionally, current scaling effects were observed by performing CWA precursor experiments at an increased current of 1.5 MA using a load current multiplier. Our results show an increase in amore » linear radiation yield of ~50% (16 versus 10 kJ/cm) for the experiments at increased current. However, plasma conditions inferred through the modeling of X-ray time-gated spectra are very similar for the precursor plasma in both current conditions.« less

Multiple socioeconomic determinants of weight gain: the Helsinki Health Study.

PubMed

Loman, Tina; Lallukka, Tea; Laaksonen, Mikko; Rahkonen, Ossi; Lahelma, Eero

2013-03-22

Socioeconomic differences in weight gain have been found, but several socioeconomic determinants have not been simultaneously studied using a longitudinal design. The aim of this study was to examine multiple socioeconomic determinants of weight gain. Mail surveys were conducted in 2000-2002 among 40 to 60-year old employees of the City of Helsinki, Finland (n = 8,960, response rate 67%). A follow-up survey was conducted among the baseline respondents in 2007 with a mean follow-up of 5 to 7 years (n = 7,332, response rate 83%). The outcome measure was weight gain of 5 kg or more over the follow-up. Socioeconomic position was measured by parental education, childhood economic difficulties, own education, occupational class, household income, home ownership and current economic difficulties. Multivariable logistic regression models were fitted adjusting simultaneously for all covariates in the final model. Of women 27% and of men 24% gained 5 kg or more in weight over the follow-up. Among women, after adjusting for age, baseline weight and all socioeconomic determinants, those with basic (OR 1.40 95% CI 1.11-1.76) or intermediate education (OR 1.43 95% CI 1.08-1.90), renters (OR 1.18 95% CI 1.03-1.36) and those with occasional (OR 1.19 95% CI 1.03-1.38) or frequent (OR 1.50 95% CI 1.26-1.79) economic difficulties had increased risk of weight gain. Among men, after full adjustment, having current frequent economic difficulties (OR 1.70 95% CI 1.15-2.49) remained associated with weight gain. Current economic difficulties among both women and men, and among women low education and renting, were associated with weight gain. Prevention of weight gain among ageing people would benefit from focusing in particular on those with economic difficulties.

Determination of plasma density from data on the ion current to cylindrical and planar probes

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

Voloshin, D. G., E-mail: dvoloshin@mics.msu.su; Vasil’eva, A. N.; Kovalev, A. S.

2016-12-15

To improve probe methods of plasma diagnostics, special probe measurements were performed and numerical models describing ion transport to a probe with allowance for collisions were developed. The current–voltage characteristics of cylindrical and planar probes were measured in an RF capacitive discharge in argon at a frequency of 81 MHz and plasma densities of 10{sup 10}–10{sup 11} cm{sup –3}, typical of modern RF reactors. 1D and 2D numerical models based on the particle-in-cell method with Monte Carlo collisions for simulating ion motion and the Boltzmann equilibrium for electrons are developed to describe current collection by a probe. The models weremore » used to find the plasma density from the ion part of the current–voltage characteristic, study the effect of ion collisions, and verify simplified approaches to determining the plasma density. A 1D hydrodynamic model of the ion current to a cylindrical probe with allowance for ion collisions is proposed. For a planar probe, a method to determine the plasma density from the averaged numerical results is developed. A comparative analysis of different approaches to calculating the plasma density from the ion current to a probe is performed.« less

A Circular Microstrip Antenna Sensor for Direction Sensitive Strain Evaluation.

PubMed

Lopato, Przemyslaw; Herbko, Michal

2018-01-20

In this paper, a circular microstrip antenna for stress evaluation is studied. This kind of microstrip sensor can be utilized in structural health monitoring systems. Reflection coefficient S 11 is measured to determine deformation/strain value. The proposed sensor is adhesively connected to the studied sample. Applied strain causes a change in patch geometry and influences current distribution both in patch and ground plane. Changing the current flow in patch influences the value of resonant frequency. In this paper, two different resonant frequencies were analysed because in each case, different current distributions in patch were obtained. The sensor was designed for operating frequency of 2.5 GHz (at fundamental mode), which results in a diameter less than 55 mm. Obtained sensitivity was up to 1 MHz/100 MPa, resolution depends on utilized vector network analyser. Moreover, the directional characteristics for both resonant frequencies were defined, studied using numerical model and verified by measurements. Thus far, microstrip antennas have been used in deformation measurement only if the direction of external force was well known. Obtained directional characteristics of the sensor allow the determination of direction and value of stress by one sensor. This method of measurement can be an alternative to the rosette strain gauge.

STUDIES ON THE FORMATION AND IONIZATION OF THE COMPOUNDS OF CASEIN WITH ALKALI

PubMed Central

Greenberg, David M.; Schmidt, Carl L. A.

1924-01-01

1. The deposition of casein on a platinum anode which takes place on the passage of a direct current through solutions of alkali caseinates was quantitatively studied, and it was found that: (a) the amount of casein which is deposited is directly proportional to the current, i.e. it obeys Faraday's law; (b) the amount of casein deposited is inversely proportional (within the limits studied) to the amount of alkali which is combined with the casein. 2. A method of determining the transport numbers of proteins insoluble at their isoelectric point has been developed. 3. A titration method for determining the amount of alkali in a casein solution is given. 4. Data from the results of transference experiments on sodium caseinate, potassium caseinate, cesium caseinate, and rubidium caseinate solutions are given. It is shown that the data are best explained on the assumption that in these solutions the carriers of the current are alkali metal cations and casein anions. 5. On the basis of our transference results an explanation is given of the results which were obtained by Robertson and by Haas in their migration experiments. PMID:19872135

A State-Wide Survey of South Australian Secondary Schools to Determine the Current Emphasis on Ergonomics and Computer Use

ERIC Educational Resources Information Center

Sawyer, Janet; Penman, Joy

2012-01-01

This study investigated the pattern of teaching of healthy computing skills to high school students in South Australia. A survey approach was used to collect data, specifically to determine the emphasis placed by schools on ergonomics that relate to computer use. Participating schools were recruited through the Department for Education and Child…

The condition of browse plants at the Theodore Roosevelt Memorial Ranch (TRMR)

USGS Publications Warehouse

Keigley, R.B.; Olson, Gary R.

2001-01-01

As background for a more comprehensive study, we collected data in September and October 1999 from which to assess the impact of ungulates on browse plants. There were three general objectives: 1) determine the current level of browsing intensity, 2) reconstruct histories of browsing, and 3) determine the effect of browsing on rate of stem growth.

Laser Scanning Technology as Part of a Comprehensive Condition Assessment for Covered Bridges

Treesearch

Brian K. Brashaw; Samuel Anderson; Robert J. Ross

2015-01-01

New noncontact technologies have been developed and implemented for determining as-built condition and current dimensions for a wide variety of objects and buildings. In this study, a three-dimensional laser scanner was used to determine the dimensions and visual condition of a historic bridge in the Amnicon Falls State Park in northern Wisconsin. 3D scanning provides...

Using IEP Goals and Objectives to Teach Paragraph Writing to High School Students with Physical and Cognitive Disabilities

ERIC Educational Resources Information Center

Konrad, Moira; Trela, Katherine; Test, David W.

2006-01-01

Current research and legislation show a need for special education instruction to be more closely aligned with general education curriculum and develop strategies that support the development of self determination skills in students with disabilities. The present study embeds self-determination skills of writing annual goals and objectives in the…

Student Motivation and the "Feel Good" Factor: An Empirical Examination of Motivational Predictors of University Service Quality Evaluation

ERIC Educational Resources Information Center

Chong, Yit Sean; Ahmed, Pervaiz K.

2015-01-01

With the globalisation of the higher education industry, service quality in the higher education services is seen as a vital factor in determining a university's competitive advantage. The purpose of this study is to extend current conceptualisation of quality research in higher education by investigating the influence of self-determination and…

Investigation of the Challenges, Mentoring Needs, and Support for Business and Marketing Teachers

ERIC Educational Resources Information Center

Yohon, Teresa

2005-01-01

The purpose of this study was to determine the challenges that new business/marketing teachers face as well as the current support structures available to them and to determine experienced business/marketing teachers perceptions of the challenges faced by new teachers as well as the types of support that they were willing to provide to new…

Morphological Analysis in Context versus Isolation: Use of a Dynamic Assessment Task with School-Age Children

ERIC Educational Resources Information Center

Ram, Gayatri; Marinellie, Sally A.; Benigno, Joann; McCarthy, John

2013-01-01

Purpose: The current study investigated the ability of typically developing children in Grades 3 and 5 to use morphological analysis to determine the meanings of derived words with and without context clues. Also of interest was the relation between children's reading practices and their performance in determining the meanings of derived words.…

Motivation, self-determination, and long-term weight control

PubMed Central

2012-01-01

This article explores the topics of motivation and self-regulation in the context of weight management and related behaviors. We focus on the role of a qualitative approach to address motivation - not only considering the level but also type of motivation - in weight control and related behaviors. We critically discuss the operationalization of motivation in current weight control programs, present a complementary approach to understanding motivation based on self-determination theory, and review empirical findings from weight control studies that have used self-determination theory measures and assessed their association with weight outcomes. Weight loss studies which used Motivational Interviewing (MI) are also reviewed, considering MI's focus on enhancing internal motivation. We hypothesize that current weight control interventions may have been less successful with weight maintenance in part due to their relative disregard of qualitative dimensions of motivation, such as level of perceived autonomy, often resulting in a motivational disconnect between weight loss and weight-related behaviors. We suggest that if individuals fully endorse weight loss-related behavioral goals and feel not just competent but also autonomous about reaching them, as suggested by self-determination theory, their efforts are more likely to result in long-lasting behavior change. PMID:22385818

Motivation, self-determination, and long-term weight control.

PubMed

Teixeira, Pedro J; Silva, Marlene N; Mata, Jutta; Palmeira, António L; Markland, David

2012-03-02

This article explores the topics of motivation and self-regulation in the context of weight management and related behaviors. We focus on the role of a qualitative approach to address motivation--not only considering the level but also type of motivation--in weight control and related behaviors. We critically discuss the operationalization of motivation in current weight control programs, present a complementary approach to understanding motivation based on self-determination theory, and review empirical findings from weight control studies that have used self-determination theory measures and assessed their association with weight outcomes. Weight loss studies which used Motivational Interviewing (MI) are also reviewed, considering MI's focus on enhancing internal motivation. We hypothesize that current weight control interventions may have been less successful with weight maintenance in part due to their relative disregard of qualitative dimensions of motivation, such as level of perceived autonomy, often resulting in a motivational disconnect between weight loss and weight-related behaviors. We suggest that if individuals fully endorse weight loss-related behavioral goals and feel not just competent but also autonomous about reaching them, as suggested by self-determination theory, their efforts are more likely to result in long-lasting behavior change.

Effect of resistivity profile on current decay time of initial phase of current quench in neon-gas-puff inducing disruptions of JT-60U

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

Kawakami, S.; Ohno, N.; Shibata, Y.

2013-11-15

According to an early work [Y. Shibata et al., Nucl. Fusion 50, 025015 (2010)] on the behavior of the plasma current decay in the JT-60U disruptive discharges caused by the radiative collapse with a massive neon-gas-puff, the increase of the internal inductance mainly determined the current decay time of plasma current during the initial phase of current quench. To investigate what determines the increase of the internal inductance, we focus attention on the relationship between the electron temperature (or the resistivity) profile and the time evolution of the current density profile and carry out numerical calculations. As a result, wemore » find the reason of the increase of the internal inductance: The current density profile at the start of the current quench is broader than an expected current density profile in the steady state, which is determined by the temperature (or resistivity) profile. The current density profile evolves into peaked one and the internal inductance is increasing.« less

Power flow analysis and optimal locations of resistive type superconducting fault current limiters.

PubMed

Zhang, Xiuchang; Ruiz, Harold S; Geng, Jianzhao; Shen, Boyang; Fu, Lin; Zhang, Heng; Coombs, Tim A

2016-01-01

Based on conventional approaches for the integration of resistive-type superconducting fault current limiters (SFCLs) on electric distribution networks, SFCL models largely rely on the insertion of a step or exponential resistance that is determined by a predefined quenching time. In this paper, we expand the scope of the aforementioned models by considering the actual behaviour of an SFCL in terms of the temperature dynamic power-law dependence between the electrical field and the current density, characteristic of high temperature superconductors. Our results are compared to the step-resistance models for the sake of discussion and clarity of the conclusions. Both SFCL models were integrated into a power system model built based on the UK power standard, to study the impact of these protection strategies on the performance of the overall electricity network. As a representative renewable energy source, a 90 MVA wind farm was considered for the simulations. Three fault conditions were simulated, and the figures for the fault current reduction predicted by both fault current limiting models have been compared in terms of multiple current measuring points and allocation strategies. Consequently, we have shown that the incorporation of the E - J characteristics and thermal properties of the superconductor at the simulation level of electric power systems, is crucial for estimations of reliability and determining the optimal locations of resistive type SFCLs in distributed power networks. Our results may help decision making by distribution network operators regarding investment and promotion of SFCL technologies, as it is possible to determine the maximum number of SFCLs necessary to protect against different fault conditions at multiple locations.

Designing Epidemiology Studies to Determine the Incidence and Prevalence of Encapsulating Peritoneal Sclerosis (EPS).

PubMed

Nitsch, Dorothea; Davenport, Andrew

2015-12-01

The reported incidence and prevalence of encapsulating peritoneal sclerosis (EPS) varies markedly between North America, Europe, Japan, and Australia. Although this could reflect differences in clinical practice patterns and access to transplantation as there is no current test for early detection, and some patients may present many years after discontinuation of peritoneal dialysis (PD), there are concerns about under-reporting, particularly for those with milder forms. Currently, only PD vintage has been identified as a significant risk factor for developing EPS, although some patients can develop EPS within months of starting PD. As such, there is a need for epidemiological studies to determine the incidence and prevalence of EPS to allow for patient education and counselling in terms of dialysis modality choice and length of treatment. In addition, carefully designed epidemiological studies could potentially allow for the identification of risk factors and bio-markers that could then be used to identify patients at increased risk of developing EPS in the future. Typically, studies to date have been underpowered with inadequate longitudinal follow-up. We review the different types of epidemiological studies and provide information as to the number of patients to be recruited and the duration of follow-up required to determine the incidence and prevalence of EPS. Copyright © 2015 International Society for Peritoneal Dialysis.

Impacts of proposed RCRA regulations and other related federal environmental regulations on fossil fuel-fired facilities: Final report, Volume 3

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

Not Available

1987-03-01

Estimation of the costs associated with implementation of the Resource Conservation and Recovery Act (RCRA) regulations for non-hazardous and hazardous material disposal in the utility industry are provided. These costs are based on engineering studies at a number of coal-fired power plants in which the costs for hazardous and non-hazardous disposal are compared to the costs developed for the current practice design for each utility. The relationship of the three costs is displayed. The emphasis of this study is on the determination of incremental costs rather than the absolute costs for each case (current practice, non-hazardous, or hazardous). For themore » purpose of this project, the hazardous design cost was determined for both minimum and maximum compliance.« less

The prevalence and predictors of metabolically healthy obesity in obese rural population of China: a cross-sectional study.

PubMed

Zhang, Naijin; Chen, Yintao; Guo, Xiaofan; Sun, Guozhe; Sun, Yingxian

2017-03-01

Till now, no evidence illustrates the prevalence and predictors of metabolically healthy obesity (MHO) in rural areas of China. The objective of this study was, firstly, to examine the prevalence of MHO in rural areas of China, and identify contributing determinants of MHO, Secondly, to comprehensively investigate to the different characteristics between MHO and metabolically unhealthy obesity (MUO). We conducted a population-based cross-sectional study of 2037 participants with obesity in rural Liaoning Province during 2012-2013. Obesity was defined as BMI ≥28 kg/m 2 and metabolically healthy was defined as not having the metabolic syndrome. The prevalence of MHO was 23.1%, and significantly decreased with advancing age in female group. However there was no significant tendency with advancing age in male group. Independent determinant factors for MHO were age <55 years (odds ratio [OR] 1.659; p = .001), non-current smoking (OR 1.397; p = .038), pre-menopause (OR 1.648; p = .030) and non-hyperuricemia (OR 2.317; p < .001), whereas race, gender, diet score, current drinking, marriage, sleep duration, hyperhomocysteinemia, levels of physical activity, annual income and educational status were not significant contributors. In conclusion, we found that age <55 years, non-current smoking, pre-menopause and non-hyperuricemia were identified as independent determinant factors for MHO in this population.

Analysis of reliable sub-ns spin-torque switching under transverse bias magnetic fields

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

D'Aquino, M., E-mail: daquino@uniparthenope.it; Perna, S.; Serpico, C.

2015-05-07

The switching process of a magnetic spin-valve nanosystem subject to spin-polarized current pulses is considered. The dependence of the switching probability on the current pulse duration is investigated. The further application of a transverse field along the intermediate anisotropy axis of the particle is used to control the quasi-random relaxation of magnetization to the reversed magnetization state. The critical current amplitudes to realize the switching are determined by studying the phase portrait of the Landau-Lifshtz-Slonczewski dynamics. Macrospin numerical simulations are in good agreement with the theoretical prediction and demonstrate reliable switching even for very short (below 100 ps) current pulses.

Mist characterization in drilling 1018 steel

NASA Astrophysics Data System (ADS)

Cole, Ian

Minimum quantity lubrication replaces the traditional method of flood cooling with small amounts of high-efficient lubrication. Limited studies have been performed to determine the characteristics of mist produced during MQL. This study investigated the mist concentration levels produced while drilling 1018 steel using a vegetable based lubricant. ANOVA was performed to determine whether speed and feed rates or their interactions have a significant effect on mist concentration levels and particle diameter. It was observed that the concentration levels obtained under all four speed and feed rate combinations studied exceeded the current OSHA and NIOSH standards.

Theoretical model and experimental investigation of current density boundary condition for welding arc study

NASA Astrophysics Data System (ADS)

Boutaghane, A.; Bouhadef, K.; Valensi, F.; Pellerin, S.; Benkedda, Y.

2011-04-01

This paper presents results of theoretical and experimental investigation of the welding arc in Gas Tungsten Arc Welding (GTAW) and Gas Metal Arc Welding (GMAW) processes. A theoretical model consisting in simultaneous resolution of the set of conservation equations for mass, momentum, energy and current, Ohm's law and Maxwell equation is used to predict temperatures and current density distribution in argon welding arcs. A current density profile had to be assumed over the surface of the cathode as a boundary condition in order to make the theoretical calculations possible. In stationary GTAW process, this assumption leads to fair agreement with experimental results reported in literature with maximum arc temperatures of ~21 000 K. In contrast to the GTAW process, in GMAW process, the electrode is consumable and non-thermionic, and a realistic boundary condition of the current density is lacking. For establishing this crucial boundary condition which is the current density in the anode melting electrode, an original method is setup to enable the current density to be determined experimentally. High-speed camera (3000 images/s) is used to get geometrical dimensions of the welding wire used as anode. The total area of the melting anode covered by the arc plasma being determined, the current density at the anode surface can be calculated. For a 330 A arc, the current density at the melting anode surface is found to be of 5 × 107 A m-2 for a 1.2 mm diameter welding electrode.

Misclassification rates for current smokers misclassified as nonsmokers.

PubMed

Wells, A J; English, P B; Posner, S F; Wagenknecht, L E; Perez-Stable, E J

1998-10-01

This paper provides misclassification rates for current cigarette smokers who report themselves as nonsmokers. Such rates are important in determining smoker misclassification bias in the estimation of relative risks in passive smoking studies. True smoking status, either occasional or regular, was determined for individual current smokers in 3 existing studies of nonsmokers by inspecting the cotinine levels of body fluids. The new data, combined with an approximately equal amount in the 1992 Environmental Protection Agency (EPA) report on passive smoking and lung cancer, yielded misclassification rates that not only had lower standard errors but also were stratified by sex and US minority majority status. The misclassification rates for the important category of female smokers misclassified as never smokers were, respectively, 0.8%, 6.0%, 2.8%, and 15.3% for majority regular, majority occasional, US minority regular, and US minority occasional smokers. Misclassification rates for males were mostly somewhat higher. The new information supports EPA's conclusion that smoker misclassification bias is small. Also, investigators are advised to pay attention to minority/majority status of cohorts when correcting for smoker misclassification bias.

Study of carrier-mobility of organic thin film by dark-injection time-of-flight and electric-field-induced optical second-harmonic generation measurements

NASA Astrophysics Data System (ADS)

Li, Xin; Sunaga, Masashi; Taguchi, Dai; Manaka, Takaaki; Lin, Hong; Iwamoto, Mitsumasa

2017-06-01

By using dark-injection time-of-flight (ToF) and time-resolved electric-field-induced optical second-harmonic generation (EFISHG) measurements, we studied carrier mobility μ of pentacene (Pen) thin film of ITO/Pen/Al and Au/Pen/polyimide/ITO diodes where pentacene film is ∼100 nm in thickness. ToF showed that determination of transit time tr from trace of transient currents is difficult owing to large capacitive charging current. On the other hand, optical EFISHG is free from this charging current, and allows us to calculate hole and electron mobility as μh = 1.8 ×10-4 cm2/Vs and μe = 7.6 ×10-7 cm2/Vs, respectively, by using the relation tr = d / μ ∫tc tr E (0) dt (d : Pen thickness, E (0) : electric field across Pen), instead of the conventional relationship tr =d2 / μV (V : voltage across Pen). Time-resolved EFISHG measurement is useful for the determination of carrier mobility of organic thin film in organic devices.

Quantitative Detection of Cracks in Steel Using Eddy Current Pulsed Thermography.

PubMed

Shi, Zhanqun; Xu, Xiaoyu; Ma, Jiaojiao; Zhen, Dong; Zhang, Hao

2018-04-02

Small cracks are common defects in steel and often lead to catastrophic accidents in industrial applications. Various nondestructive testing methods have been investigated for crack detection; however, most current methods focus on qualitative crack identification and image processing. In this study, eddy current pulsed thermography (ECPT) was applied for quantitative crack detection based on derivative analysis of temperature variation. The effects of the incentive parameters on the temperature variation were analyzed in the simulation study. The crack profile and position are identified in the thermal image based on the Canny edge detection algorithm. Then, one or more trajectories are determined through the crack profile in order to determine the crack boundary through its temperature distribution. The slope curve along the trajectory is obtained. Finally, quantitative analysis of the crack sizes was performed by analyzing the features of the slope curves. The experimental verification showed that the crack sizes could be quantitatively detected with errors of less than 1%. Therefore, the proposed ECPT method was demonstrated to be a feasible and effective nondestructive approach for quantitative crack detection.

Life-course determinants of bone mass in young adults from a transitional rural community in India: the Andhra Pradesh Children and Parents Study (APCAPS).

PubMed

Matsuzaki, Mika; Kuper, Hannah; Kulkarni, Bharati; Radhakrishna, K V; Viljakainen, Heli; Taylor, Amy E; Sullivan, Ruth; Bowen, Liza; Tobias, Jon H; Ploubidis, George B; Wells, Jonathan C; Prabhakaran, Dorairaj; Davey Smith, George; Ebrahim, Shah; Ben-Shlomo, Yoav; Kinra, Sanjay

2014-06-01

Undernutrition and physical inactivity are both associated with lower bone mass. This study aimed to investigate the combined effects of early-life undernutrition and urbanized lifestyles in later life on bone mass accrual in young adults from a rural community in India that is undergoing rapid socioeconomic development. This was a prospective cohort study of participants of the Hyderabad Nutrition Trial (1987-1990), which offered balanced protein-calorie supplementation to pregnant women and preschool children younger than 6 y in the intervention villages. The 2009-2010 follow-up study collected data on current anthropometric measures, bone mineral density (BMD) measured by dual-energy X-ray absorptiometry, blood samples, diet, physical activity, and living standards of the trial participants (n = 1446, aged 18-23 y). Participants were generally lean and had low BMD [mean hip BMD: 0.83 (women), 0.95 (men) g/cm²; lumbar spine: 0.86 (women), 0.93 (men) g/cm²]. In models adjusted for current risk factors, no strong evidence of a positive association was found between BMD and early-life supplementation. On the other hand, current lean mass and weight-bearing physical activity were positively associated with BMD. No strong evidence of an association was found between BMD and current serum 25-hydroxyvitamin D or dietary intake of calcium, protein, or calories. Current lean mass and weight-bearing physical activity were more important determinants of bone mass than was early-life undernutrition in this population. In transitional rural communities from low-income countries, promotion of physical activity may help to mitigate any potential adverse effects of early nutritional disadvantage.

Life-course determinants of bone mass in young adults from a transitional rural community in India: the Andhra Pradesh Children and Parents Study (APCAPS)123

PubMed Central

Matsuzaki, Mika; Kuper, Hannah; Kulkarni, Bharati; Radhakrishna, KV; Viljakainen, Heli; Taylor, Amy E; Sullivan, Ruth; Bowen, Liza; Tobias, Jon H; Ploubidis, George B; Wells, Jonathan C; Prabhakaran, Dorairaj; Davey Smith, George; Ebrahim, Shah; Ben-Shlomo, Yoav; Kinra, Sanjay

2014-01-01

Background: Undernutrition and physical inactivity are both associated with lower bone mass. Objective: This study aimed to investigate the combined effects of early-life undernutrition and urbanized lifestyles in later life on bone mass accrual in young adults from a rural community in India that is undergoing rapid socioeconomic development. Design: This was a prospective cohort study of participants of the Hyderabad Nutrition Trial (1987–1990), which offered balanced protein-calorie supplementation to pregnant women and preschool children younger than 6 y in the intervention villages. The 2009–2010 follow-up study collected data on current anthropometric measures, bone mineral density (BMD) measured by dual-energy X-ray absorptiometry, blood samples, diet, physical activity, and living standards of the trial participants (n = 1446, aged 18–23 y). Results: Participants were generally lean and had low BMD [mean hip BMD: 0.83 (women), 0.95 (men) g/cm2; lumbar spine: 0.86 (women), 0.93 (men) g/cm2]. In models adjusted for current risk factors, no strong evidence of a positive association was found between BMD and early-life supplementation. On the other hand, current lean mass and weight-bearing physical activity were positively associated with BMD. No strong evidence of an association was found between BMD and current serum 25-hydroxyvitamin D or dietary intake of calcium, protein, or calories. Conclusions: Current lean mass and weight-bearing physical activity were more important determinants of bone mass than was early-life undernutrition in this population. In transitional rural communities from low-income countries, promotion of physical activity may help to mitigate any potential adverse effects of early nutritional disadvantage. PMID:24695898

Effect of direct electric current on contaminants removal from the peat water with continuous system

NASA Astrophysics Data System (ADS)

Amri, I.; Azis, A.; Drastinawati

2018-04-01

This research was analysed the essentially of treat peat water using an electric current. Initially, the characterization of peat water was determined including of three parameters they are pH, colour, and conductivity solution exhibited values that exceeded the water standard limit. There are two factors influencing the electric coagulation such as electric current and voltage that were observed in the continous study. The results obtained indicated that the majority of the an electric current were very effective for removing TDS, and pH. The research variable for the voltage from 23,5 to 42,5 volt and the electric current from 2,2 to 4,1. The optimum electric current and voltage was found around 1,5 Ampere and 25 volt, it was exhibited at 4 L/minute. In unit study, continous electric reactor showed that the optimal reduction on the 20 minutes treatment were found pH = 7, 256 ppm. It was meet to the minimum standard government permition.

Computational modeling of the effect of external electron injection into a direct-current microdischarge

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

Panneer Chelvam, Prem Kumar; Raja, Laxminarayan L.

2015-12-28

Electron emission from the electrode surface plays an important role in determining the structure of a direct-current microdischarge. Here we have developed a computational model of a direct-current microdischarge to study the effect of external electron injection from the cathode surface into the discharge to manipulate its properties. The model provides a self-consistent, multi-species, multi-temperature fluid representation of the plasma. A microdischarge with a metal-insulator-metal configuration is chosen for this study. The effect of external electron injection on the structure and properties of the microdischarge is described. The transient behavior of the microdischarge during the electron injection is examined. Themore » nonlinearities in the dynamics of the plasma result in a large increase of conduction current after active electron injection. For the conditions simulated a switching time of ∼100 ns from a low-current to high-current discharge state is realized.« less

Improving the aluminum-air battery system for use in electrical vehicles

NASA Astrophysics Data System (ADS)

Yang, Shaohua

The objectives of this study include improvement of the efficiency of the aluminum/air battery system and demonstration of its ability for vehicle applications. The aluminum/air battery system can generate enough energy and power for driving ranges and acceleration similar to that of gasoline powered cars. Therefore has the potential to be a power source for electrical vehicles. Aluminum/air battery vehicle life cycle analysis was conducted and compared to that of lead/acid and nickel-metal hydride vehicles. Only the aluminum/air vehicles can be projected to have a travel range comparable to that of internal combustion engine vehicles (ICE). From this analysis, an aluminum/air vehicle is a promising candidate compared to ICE vehicles in terms of travel range, purchase price, fuel cost, and life cycle cost. We have chosen two grades of Al alloys (Al alloy 1350, 99.5% and Al alloy 1199, 99.99%) in our study. Only Al 1199 was studied extensively using Na 2SnO3 as an electrolyte additive. We then varied concentration and temperature, and determined the effects on the parasitic (corrosion) current density and open circuit potential. We also determined cell performance and selectivity curves. To optimize the performance of the cell based on our experiments, the recommended operating conditions are: 3--4 N NaOH, about 55°C, and a current density of 150--300 mA/cm2. We have modeled the cell performance using the equations we developed. The model prediction of cell performance shows good agreement with experimental data. For better cell performance, our model studies suggest use of higher electrolyte flow rate, smaller cell gap, higher conductivity and lower parasitic current density. We have analyzed the secondary current density distributions in a two plane, parallel Al/air cell and a wedge-type Al/air cell. The activity of the cathode has a large effect on the local current density. With increases in the cell gap, the local current density increases, but the increase is not as significant as the increase in the current density away from the entrance. By extending the cathode below the anode, the high local current density can be reduced.

Nearshore disposal of fine-grained sediment in a high-energy environment: Santa Cruz Harbor case study

USGS Publications Warehouse

Cronin, Katherine; van Ormondt, Maarten; Storlazzi, Curt D.; Presto, Katherine; Tonnon, Pieter K.; Rosati, Julie D.; Wang, Ping; Roberts, Tiffany M.

2011-01-01

Current regulations in California prohibit the disposal of more than 20% fine-grained sediment in the coastal zone; this threshold is currently being investigated to determine if this environmental regulation can be improved upon. A field monitoring and numerical modeling experiment took place late 2 009 to determine the fate of fine-grained dredge disposal material from Santa Cruz Harbor, California, U.S.A. A multi-nested, hydrodynamic-sediment transport modeling approach was used to simulate the direction and dispersal of the dredge plume. Result s show that the direction and dispersal of the plume was influenced by the wave  climate, a large proportion of which moved in a easterly direction during wave events. Therefore it is vitally important to accurately simulate the tides, waves, currents, temperature and salinity when modeling the dispersal of the fine-grained dredge plume. 

Field Performance of Photovoltaic Systems in the Tucson Desert

NASA Astrophysics Data System (ADS)

Orsburn, Sean; Brooks, Adria; Cormode, Daniel; Greenberg, James; Hardesty, Garrett; Lonij, Vincent; Salhab, Anas; St. Germaine, Tyler; Torres, Gabe; Cronin, Alexander

2011-10-01

At the Tucson Electric Power (TEP) solar test yard, over 20 different grid-connected photovoltaic (PV) systems are being tested. The goal at the TEP solar test yard is to measure and model real-world performance of PV systems and to benchmark new technologies such as holographic concentrators. By studying voltage and current produced by the PV systems as a function of incident irradiance, and module temperature, we can compare our measurements of field-performance (in a harsh desert environment) to manufacturer specifications (determined under laboratory conditions). In order to measure high-voltage and high-current signals, we designed and built reliable, accurate sensors that can handle extreme desert temperatures. We will present several benchmarks of sensors in a controlled environment, including shunt resistors and Hall-effect current sensors, to determine temperature drift and accuracy. Finally we will present preliminary field measurements of PV performance for several different PV technologies.

Reporting suicide attempts: consistency and its determinants in a large mental health study.

PubMed

Eikelenboom, Merijn; Smit, Johannes H; Beekman, Aartjan T F; Kerkhof, Ad J F M; Penninx, Brenda W J H

2014-06-01

A lifetime history (LTH) of suicide attempts (SAs) is frequently assessed in mental health surveys. However, little is known about the reliability of assessing a LTH of SA. This study examined the consistency and its determinants of reporting a LTH of SA in a large cohort of persons with a history of depression and/or anxiety. Data are from the baseline and two-year assessments of the Netherlands Study of Depression and Anxiety. Persons with a Composite International Diagnostic Interview (CIDI)-based lifetime depressive and/or anxiety disorder (N = 1973) constitute the study sample. A LTH of SAs was assessed at baseline and at two-year follow-up. Of the persons who reported at either interview a LTH of SAs, more than one-third did not report this consistent at both interviews. Moreover, indications were found for more consistent reporting among persons with a higher number of SAs and among persons with current (severe) psychopathology as compared to those with remitted or less severe current psychopathology. Our results showed that even a salient topic as a history of SAs is prone for reporting errors, and that current psychological state influences reporting of a LTH of SAs. Copyright © 2014 John Wiley & Sons, Ltd.

Analysis of the U.S. geological survey streamgaging network

USGS Publications Warehouse

Scott, A.G.

1987-01-01

This paper summarizes the results from the first 3 years of a 5-year cost-effectiveness study of the U.S. Geological Survey streamgaging network. The objective of the study is to define and document the most cost-effective means of furnishing streamflow information. In the first step of this study, data uses were identified for 3,493 continuous-record stations currently being operated in 32 States. In the second step, evaluation of alternative methods of providing streamflow information, flow-routing models, and regression models were developed for estimating daily flows at 251 stations of the 3,493 stations analyzed. In the third step of the analysis, relationships were developed between the accuracy of the streamflow records and the operating budget. The weighted standard error for all stations, with current operating procedures, was 19.9 percent. By altering field activities, as determined by the analyses, this could be reduced to 17.8 percent. The existing streamgaging networks in four Districts were further analyzed to determine the impacts that satellite telemetry would have on the cost effectiveness. Satellite telemetry was not found to be cost effective on the basis of hydrologic data collection alone, given present cost of equipment and operation.This paper summarizes the results from the first 3 years of a 5-year cost-effectiveness study of the U. S. Geological Survey streamgaging network. The objective of the study is to define and document the most cost-effective means of furnishing streamflow information. In the first step of this study, data uses were identified for 3,493 continuous-record stations currently being operated in 32 States. In the second step, evaluation of alternative methods of providing streamflow information, flow-routing models, and regression models were developed for estimating daily flows at 251 stations of the 3, 493 stations analyzed. In the third step of the analysis, relationships were developed between the accuracy of the streamflow records and the operating budget. The weighted standard error for all stations, with current operating procedures, was 19. 9 percent. By altering field activities, as determined by the analyses, this could be reduced to 17. 8 percent. Additional study results are discussed.

Skin Penetration Enhancement by Natural Oils for Dihydroquercetin Delivery.

PubMed

Čižinauskas, Vytis; Elie, Nicolas; Brunelle, Alain; Briedis, Vitalis

2017-09-12

Natural oils are commonly used in topical pharmaceutical formulations as emulsifiers, stabilizers or solubility enhancers. They are presented as safe and inert components, mainly used for formulation purposes. It is confirmed that natural oils can affect the skin penetration of various substances. Fatty acids are mainly responsible for this effect. Current understanding lacks reliable scientific data on penetration of natural oils into the skin and their skin penetration enhancement potential. In the current study, fatty acid content analysis was used to determine the principal fatty acids in soybean, olive, avocado, sea-buckthorn pulp, raspberry seed and coconut oils. Time of flight secondary ion mass spectrometry bioimaging was used to determine the distribution of these fatty acids in human skin ex vivo after application of the oils. Skin penetration enhancement ratios were determined for a perspective antioxidant compound dihydroquercetin. The results demonstrated skin penetration of fatty acids from all oils tested. Only soybean and olive oils significantly increased the skin distribution of dihydroquercetin and can be used as skin penetration enhancers. However, no correlation can be determined between the fatty acids' composition and skin penetration enhancement using currently available methodological approaches. This indicates that potential chemical penetration enhancement should be evaluated during formulation of topically applied products containing natural oils.

Incorporation of web-based applications and online resources in undergraduate medical education in the Irish Republic. Can new changes be incorporated in the current medical curriculum?

PubMed Central

Dhatt, Karanvir Singh; Kaliaperumal, Chandrasekaran

2014-01-01

Background/Aim: Significant change has been happening in the introduction of technology in medical teaching all over the world. We aim to determine if the undergraduate medical students and teachers are open to incorporating changes in the current medical curriculum or if there is a need for the same in the Republic of Ireland. Materials and Methods: A cross-sectional study involving 202 participants of whom 152 were medical students and 50 medical professionals (teachers and hospital doctors) were carried out involving three different medical universities namely; University College Cork (UCC), University College Dublin (UCD), and National University of Ireland in Galway (NUIG). Participants were requested to answer a series of 15 questions designed incorporating various fields of technology necessary for the study. The data was collected and analyzed using Statistical Package for Social Sciences (SPSS) software to determine statistical significance. Results: The participants overall had a positive attitude toward the utility of modern technology and web-based applications in current medical curriculum. Ninety-one percent of the participants preferred the introduction of modern technology into medical education and 7% were against the idea and a further 2% of them remained undecided. Conclusion: There seems to be a “technology gap” in the current undergraduate medical curriculum in Ireland. A large-scale study involving more participants from all the medical schools in Ireland is recommended. We believe, changes can be brought into the current medical teaching and learning to make the process more fruitful and successful. PMID:25097432

Influence of parental education, childhood adversities, and current living conditions on daily smoking in early adulthood.

PubMed

Kestilä, Laura; Koskinen, Seppo; Martelin, Tuija; Rahkonen, Ossi; Pensola, Tiina; Pirkola, Sami; Patja, Kristiina; Aromaa, Arpo

2006-12-01

To assess the association of parental education, childhood living conditions and adversities with daily smoking in early adulthood and to analyse the effect of the respondent's own education, main economic activity, and current family structure on these associations. The study is based on a representative two-stage cluster sample (N = 1894, participation rate 79%) of young adults aged 18-29, in 2000, in Finland. The outcome measure is daily smoking. Parental smoking and the respondent's own education had the strongest effects on daily smoking. If both parents of the respondent were smokers, then the respondent was most likely to be a smoker too (for men OR (odds ratio) = 3.01, for women OR = 2.41 after all adjustments). Young adults in the lowest educational category had a much higher risk of daily smoking than those in the highest category (OR = 5.88 for women, 4.48 for men). For women parental divorce (OR = 2.31) and current family structure also determined daily smoking. Parental education had a strong gradient in daily smoking and the effect appeared to be mediated largely by the respondent's own educational level. Childhood living conditions are strong determinants of daily smoking. Much of their influence seems to be mediated through current living conditions, which are also determined by childhood conditions. Determinants of smoking behaviour are developed throughout the life course. The findings stress the importance of the respondent's education and parental smoking as determinants of smoking behaviour. Our results support the notion that intervention on smoking initiation and cessation should be considered throughout the life course. Parental involvement in fostering non-smoking would be important.

Ionospheric and Birkeland current distributions inferred from the MAGSAT magnetometer data

NASA Technical Reports Server (NTRS)

Zanetti, L. J.; Potemra, T. A.; Baumjohann, W.

1983-01-01

Ionospheric and field-aligned sheet current density distributions are presently inferred by means of MAGSAT vector magnetometer data, together with an accurate magnetic field model. By comparing Hall current densities inferred from the MAGSAT data and those inferred from simultaneously recorded ground based data acquired by the Scandinavian magnetometer array, it is determined that the former have previously been underestimated due to high damping of magnetic variations with high spatial wave numbers between the ionosphere and the MAGSAT orbit. Among important results of this study is noted the fact that the Birkeland and electrojet current systems are colocated. The analyses have shown a tendency for triangular rather than constant electrojet current distributions as a function of latitude, consistent with the statistical, uniform regions 1 and 2 Birkeland current patterns.

MIS capacitor studies on silicon carbide single crystals

NASA Technical Reports Server (NTRS)

Kopanski, J. J.

1990-01-01

Cubic SIC metal-insulator-semiconductor (MIS) capacitors with thermally grown or chemical-vapor-deposited (CVD) insulators were characterized by capacitance-voltage (C-V), conductance-voltage (G-V), and current-voltage (I-V) measurements. The purpose of these measurements was to determine the four charge densities commonly present in an MIS capacitor (oxide fixed charge, N(f); interface trap level density, D(it); oxide trapped charge, N(ot); and mobile ionic charge, N(m)) and to determine the stability of the device properties with electric-field stress and temperature. The section headings in the report include the following: Capacitance-voltage and conductance-voltage measurements; Current-voltage measurements; Deep-level transient spectroscopy; and Conclusions (Electrical characteristics of SiC MIS capacitors).

Theoretical derivation of anodizing current and comparison between fitted curves and measured curves under different conditions.

PubMed

Chong, Bin; Yu, Dongliang; Jin, Rong; Wang, Yang; Li, Dongdong; Song, Ye; Gao, Mingqi; Zhu, Xufei

2015-04-10

Anodic TiO2 nanotubes have been studied extensively for many years. However, the growth kinetics still remains unclear. The systematic study of the current transient under constant anodizing voltage has not been mentioned in the original literature. Here, a derivation and its corresponding theoretical formula are proposed to overcome this challenge. In this paper, the theoretical expressions for the time dependent ionic current and electronic current are derived to explore the anodizing process of Ti. The anodizing current-time curves under different anodizing voltages and different temperatures are experimentally investigated in the anodization of Ti. Furthermore, the quantitative relationship between the thickness of the barrier layer and anodizing time, and the relationships between the ionic/electronic current and temperatures are proposed in this paper. All of the current-transient plots can be fitted consistently by the proposed theoretical expressions. Additionally, it is the first time that the coefficient A of the exponential relationship (ionic current j(ion) = A exp(BE)) has been determined under various temperatures and voltages. And the results indicate that as temperature and voltage increase, ionic current and electronic current both increase. The temperature has a larger effect on electronic current than ionic current. These results can promote the research of kinetics from a qualitative to quantitative level.

Theoretical derivation of anodizing current and comparison between fitted curves and measured curves under different conditions

NASA Astrophysics Data System (ADS)

Chong, Bin; Yu, Dongliang; Jin, Rong; Wang, Yang; Li, Dongdong; Song, Ye; Gao, Mingqi; Zhu, Xufei

2015-04-01

Anodic TiO2 nanotubes have been studied extensively for many years. However, the growth kinetics still remains unclear. The systematic study of the current transient under constant anodizing voltage has not been mentioned in the original literature. Here, a derivation and its corresponding theoretical formula are proposed to overcome this challenge. In this paper, the theoretical expressions for the time dependent ionic current and electronic current are derived to explore the anodizing process of Ti. The anodizing current-time curves under different anodizing voltages and different temperatures are experimentally investigated in the anodization of Ti. Furthermore, the quantitative relationship between the thickness of the barrier layer and anodizing time, and the relationships between the ionic/electronic current and temperatures are proposed in this paper. All of the current-transient plots can be fitted consistently by the proposed theoretical expressions. Additionally, it is the first time that the coefficient A of the exponential relationship (ionic current jion = A exp(BE)) has been determined under various temperatures and voltages. And the results indicate that as temperature and voltage increase, ionic current and electronic current both increase. The temperature has a larger effect on electronic current than ionic current. These results can promote the research of kinetics from a qualitative to quantitative level.

A Study of the Air Force’s Exception Management Process: Its Effect on Customer Service and Order Processing

DTIC Science & Technology

1991-09-01

The purpose of this study was two-fold; the first goal was to determine what the SBSS order processing is, and secondly to determine the effect the...current method of ECC management has on the SBSS order processing cycle and the level of customer service rendered by base supply. The research...revealed that exception management is a crucial component of a successful order processing function. Further, it was established that the level of customer

A Comparison of Current Naval Marksmanship Training Vs. Simulation-Based Marksmanship Training with the Use of Indoor Simulated Marksmanship Trainer (Ismt)

DTIC Science & Technology

2014-03-01

purpose of the study was to determine if the use of a simulator is at least as effective in marksmanship training as traditional dry fire techniques...determine if the use of a simulator is at least as effective in marksmanship training as traditional dry fire techniques. A between-groups study with a...marksmanship. Naval commands could use the information to effectively maintain gun qualifications for inport duty section watch bills and constant anti

Current response of a TlBr detector to {sup 137}Cs {gamma}-ray radiation

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

Gazizov, I. M., E-mail: gazizov@isotop.dubna.ru; Zaletin, V. M.; Kukushkin, V. M.

2011-05-15

The current response of a TlBr detector to {sup 137}Cs {gamma}-ray radiation has been studied in the dose-rate range 0.033-3.84 Gy/min and within the voltage range 1-300 V; the detectors are based on pure and doped TlBr crystals grown from the melt by the Bridgman-Stockbarger method. The mass fraction of Pb or Ca introduced into the TlBr crystals was 1-10 ppm for Pb and 150 ppm for Ca. The current response of nominally undoped TlBr samples was nearly linear over two decades of studied dose rates. Deep hole levels associated with cationic vacancies V{sub c}{sup -} determine the dependence ofmore » the current response on the voltage in the high electric fields. The parameters of the carriers' transport {mu}{tau} are determined. The TlBr crystals grown in vacuum and in the bromine vapor exhibit a large mobility-lifetime product of 4.3 Multiplication-Sign 10{sup -4} and 6.4 Multiplication-Sign 10{sup -5} cm{sup 2}V{sup -1}, respectively. The value of {mu}{tau} is in the range (4-9) Multiplication-Sign 10{sup -5} cm{sup 2}V{sup -1} for crystals doped with a divalent cation.« less

75 FR 9232 - Measuring Progress on Food Safety: Current Status and Future Directions; Public Workshop

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-01

... for assessing progress in food safety and associated methodological issues and to discuss potential.... The FoodNet also conducts special studies to determine risk factors for acquiring those illnesses... production, studies on the prevalence of specific pathogens in specific classes of food, and studies of...

Matters of Accuracy and Conventionality: Prior Accuracy Guides Children's Evaluations of Others' Actions

ERIC Educational Resources Information Center

Scofield, Jason; Gilpin, Ansley Tullos; Pierucci, Jillian; Morgan, Reed

2013-01-01

Studies show that children trust previously reliable sources over previously unreliable ones (e.g., Koenig, Clement, & Harris, 2004). However, it is unclear from these studies whether children rely on accuracy or conventionality to determine the reliability and, ultimately, the trustworthiness of a particular source. In the current study, 3- and…

Predicting Acceptance of Mobile Technology for Aiding Student-Lecturer Interactions: An Empirical Study

ERIC Educational Resources Information Center

Gan, Chin Lay; Balakrishnan, Vimala

2017-01-01

The current study sets out to identify determinants affecting tertiary students' behavioural intentions to use mobile technology in lectures. The study emphasises that the reason for using mobile technology in classrooms with large numbers of students is to facilitate interactions among students and lecturers. The proposed conceptual framework has…

Mathematics Achievement: Traditional Instruction and Technology-Assisted Course Delivery Methods

ERIC Educational Resources Information Center

Vilardi, Robert; Rice, Margaret L.

2014-01-01

The purpose of this study was to analyze technology-assisted course delivery methods to determine their overall effectiveness as it pertains to mathematics courses. This study analyzed both current and historical data in the areas of achievement, retention, and grade distribution for mathematics classes. The study included 14,562 students enrolled…

A Phenomenological Case Study: Teacher Bias Effects on Early Education Assessments

ERIC Educational Resources Information Center

Reynolds, Rebecca Jeannine

2012-01-01

This qualitative phenomenological case study explored the lived experiences of a purposive sample of 20 current and past early education teachers who have experience in assessing children through observational assessment. The purpose of this study was to determine if bias affects the documentation of observational assessment and the implementation…

Reading Strategies in Spanish Developmental Dyslexics

ERIC Educational Resources Information Center

Suarez-Coalla, Paz; Cuetos, Fernando

2012-01-01

Cross-linguistic studies suggest that the orthographic system determines the reading performance of dyslexic children. In opaque orthographies, the fundamental feature of developmental dyslexia is difficulty in reading accuracy, whereas slower reading speed is more common in transparent orthographies. The aim of the current study was to examine…

49 CFR 1139.3 - Cost study.

Code of Federal Regulations, 2014 CFR

2014-10-01

... service units as developed from its traffic study. Operating ratios shall be determined for the issue... anticipated on the effective date of the proposed rates, with a separation indicating projected operating ratios on two bases, namely, “based on current revenues,” and “based on proposed revenues”. Operating...

49 CFR 1139.3 - Cost study.

Code of Federal Regulations, 2013 CFR

2013-10-01

... service units as developed from its traffic study. Operating ratios shall be determined for the issue... anticipated on the effective date of the proposed rates, with a separation indicating projected operating ratios on two bases, namely, “based on current revenues,” and “based on proposed revenues”. Operating...

49 CFR 1139.3 - Cost study.

Code of Federal Regulations, 2012 CFR

2012-10-01

... service units as developed from its traffic study. Operating ratios shall be determined for the issue... anticipated on the effective date of the proposed rates, with a separation indicating projected operating ratios on two bases, namely, “based on current revenues,” and “based on proposed revenues”. Operating...

75 FR 59724 - Proposed Collection; Comment Request; Transfusion-Transmitted Retrovirus and Hepatitis Virus...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-28

...- control study design. (3) Determine nationally-representative infectious disease marker prevalence and... on current risk factors in blood donors as assessed using analytical study designs is largely... in first time donors increased. Moreover specific age, gender and race/ethnicity groups were over...

Results of an inter-laboratory study of glass formulation for the immobilization of excess plutonium

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

Peeler, D.K.

1999-12-08

The primary focus of the current study is to determine allowable loadings of feed streams containing different ratios of plutonium, uranium, and minor components into the LaBS glass and to evaluate thermal stability with respect to the DWPF pour.

Paraprofessional Education in SA DETAFE.

ERIC Educational Resources Information Center

Mills, Paul; Cesnich, Janine

A study examined the current outcomes and future of paraprofessional education provided under the auspices of South Australia's Department of Employment and Technical and Further Education (SA DETAFE). The primary objectives of the study were as follows: (1) determine whether an autonomous middle-level employment base exists in selected…

Deducing noninductive current profile from surface voltage evolution

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

Litwin, C.; Wukitch, S.; Hershkowitz, N.

Solving the resistive diffusion equation in the presence of a noninductive current source determines the time-evolution of the surface voltage. By inverting the problem the current drive profile can be determined from the surface voltage evolution. We show that under wide range of conditions the deduced profile is unique. If the conductivity profile is known, this method can be employed to infer the noninductive current profile, and, ipso facto, the profile of the total current. We discuss the application of this method to analyze the Alfven wave current drive experiments in Phaedrus-T.

Analytical and experimental study of high phase order induction motors

NASA Technical Reports Server (NTRS)

Klingshirn, Eugene A.

1989-01-01

Induction motors having more than three phases were investigated to determine their suitability for electric vehicle applications. The objective was to have a motor with a current rating lower than that of a three-phase motor. The name chosen for these is high phase order (HPO) motors. Motors having six phases and nine phases were given the most attention. It was found that HPO motors are quite suitable for electric vehicles, and for many other applications as well. They have characteristics which are as good as or better than three-phase motors for practically all applications where polyphase induction motors are appropriate. Some of the analysis methods are presented, and several of the equivalent circuits which facilitate the determination of harmonic currents and losses, or currents with unbalanced sources, are included. The sometimes large stator currents due to harmonics in the source voltages are pointed out. Filters which can limit these currents were developed. An analysis and description of these filters is included. Experimental results which confirm and illustrate much of the theory are also included. These include locked rotor test results and full-load performance with an open phase. Also shown are oscillograms which display the reduction in harmonic currents when a filter is used with the experimental motor supplied by a non-sinusoidal source.

On the threshold conditions for electron beam damage of asbestos amosite fibers in the transmission electron microscope (TEM).

PubMed

Martin, Joannie; Beauparlant, Martin; Sauvé, Sébastien; L'Espérance, Gilles

2016-12-01

Asbestos amosite fibers were investigated to evaluate the damage caused by a transmission electron microscope (TEM) electron beam. Since elemental x-ray intensity ratios obtained by energy dispersive x-ray spectroscopy (EDS) are commonly used for asbestos identification, the impact of beam damage on these ratios was evaluated. It was determined that the magnesium/silicon ratio best represented the damage caused to the fiber. Various tests showed that most fibers have a current density threshold above which the chemical composition of the fiber is modified. The value of this threshold current density varied depending on the fiber, regardless of fiber diameter, and in some cases could not be determined. The existence of a threshold electron dose was also demonstrated. This value was dependent on the current density used and can be increased by providing a recovery period between exposures to the electron beam. This study also established that the electron beam current is directly related to the damage rate above a current density of 165 A/cm 2 . The large number of different results obtained suggest, that in order to ensure that the amosite fibers are not damaged, analysis should be conducted below a current density of 100 A/cm 2 .

Direct current plasma jet at atmospheric pressure operating in nitrogen and air

NASA Astrophysics Data System (ADS)

Deng, X. L.; Nikiforov, A. Yu.; Vanraes, P.; Leys, Ch.

2013-01-01

An atmospheric pressure direct current (DC) plasma jet is investigated in N2 and dry air in terms of plasma properties and generation of active species in the active zone and the afterglow. The influence of working gases and the discharge current on plasma parameters and afterglow properties are studied. The electrical diagnostics show that discharge can be sustained in two different operating modes, depending on the current range: a self-pulsing regime at low current and a glow regime at high current. The gas temperature and the N2 vibrational temperature in the active zone of the jet and in the afterglow are determined by means of emission spectroscopy, based on fitting spectra of N2 second positive system (C3Π-B3Π) and the Boltzmann plot method, respectively. The spectra and temperature differences between the N2 and the air plasma jet are presented and analyzed. Space-resolved ozone and nitric oxide density measurements are carried out in the afterglow of the jet. The density of ozone, which is formed in the afterglow of nitrogen plasma jet, is quantitatively detected by an ozone monitor. The density of nitric oxide, which is generated only in the air plasma jet, is determined by means of mass-spectroscopy techniques.

Diffusion with Varying Drag; the Runaway Problem.

NASA Astrophysics Data System (ADS)

Rollins, David Kenneth

We study the motion of electrons in an ionized plasma of electrons and ions in an external electric field. A probability distribution function describes the electron motion and is a solution of a Fokker-Planck equation. In zero field, the solution approaches an equilibrium Maxwellian. For arbitrarily small field, electrons overcome the diffusive effects and are freely accelerated by the field. This is the electron runaway phenomenon. We treat the electric field as a small perturbation. We consider various diffusion coefficients for the one dimensional problem and determine the runaway current as a function of the field strength. Diffusion coefficients, non-zero on a finite interval are examined. Some non-trivial cases of these can be solved exactly in terms of known special functions. The more realistic case where the diffusion coefficient decays with velocity are then considered. To determine the runaway current, the equivalent Schrodinger eigenvalue problem is analysed. The smallest eigenvalue is shown to be equal to the runaway current. Using asymptotic matching a solution can be constructed which is then used to evaluate the runaway current. The runaway current is exponentially small as a function of field strength. This method is used to extract results from the three dimensional problem.

High Latitude Precipitating Energy Flux and Joule Heating During Geomagnetic Storms Determined from AMPERE Field-aligned Currents

NASA Astrophysics Data System (ADS)

Robinson, R. M.; Zanetti, L. J.; Anderson, B. J.; Korth, H.; Samara, M.; Michell, R.; Grubbs, G. A., II; Hampton, D. L.; Dropulic, A.

2016-12-01

A high latitude conductivity model based on field-aligned currents measured by the Active Magnetosphere and Planetary Electrodynamics Response Experiment (AMPERE) provides the means for complete specification of electric fields and currents at high latitudes. Based on coordinated measurements made by AMPERE and the Poker Flat Incoherent Scatter Radar, the model determines the most likely value of the ionospheric conductance from the direction, magnitude, and magnetic local time of the field-aligned current. A conductance model driven by field-aligned currents ensures spatial and temporal consistency between the calculated electrodynamic parameters. To validate the results, the Pedersen and Hall conductances were used to calculate the energy flux associated with the energetic particle precipitation. When integrated over the entire hemisphere, the total energy flux compares well with the Hemispheric Power Index derived from the OVATION-PRIME model. The conductances were also combined with the field-aligned currents to calculate the self-consistent electric field, which was then used to compute horizontal currents and Joule heating. The magnetic perturbations derived from the currents replicate most of the variations observed in ground-based magnetograms. The model was used to study high latitude particle precipitation, currents, and Joule heating for 24 magnetic storms. In most cases, the total energy input from precipitating particles and Joule heating exhibits a sharply-peaked maximum at the times of local minima in Dst, suggesting a close coupling between the ring current and the high latitude currents driven by the Region 2 field-aligned currents. The rapid increase and decrease of the high latitude energy deposition suggests an explosive transfer of energy from the magnetosphere to the ionosphere just prior to storm recovery.

Calcium Currents of Olfactory Bulb Juxtaglomerular Cells: Profile and Multiple Conductance Plateau Potential Simulation

PubMed Central

Masurkar, Arjun V.; Chen, Wei R.

2011-01-01

The olfactory glomerulus is the locus of information transfer between olfactory sensory neurons and output neurons of the olfactory bulb. Juxtaglomerular cells (JGCs) may influence intraglomerular processing by firing plateau potentials that support multiple spikes. It is unclear what inward currents mediate this firing pattern. In previous work, we characterized potassium currents of JGCs. We focus here on the inward currents using whole cell current clamp and voltage recording in a rat in vitro slice preparation, as well as computer simulation. We first showed that sodium current was not required to mediate plateau potentials. Voltage clamp characterization of calcium current (ICa) determined that ICa consisted of a slow activating, rapidly inactivating (τ10%–90% rise 6–8ms, τinactivation 38–77ms) component Icat1, similar to T-type currents, and a sustained (τinactivation≫500ms) component Icat2, likely composed of L-type and P/Q-type currents. We used computer simulation to test their roles in plateau potential firing. We robustly modeled Icat1 and Icat2 to Hodgkin-Huxley schemes (m3h and m2, respectively) and simulated a JGC plateau potential with 6 conductances: calcium currents as above, potassium currents from our prior study (A-type Ikt1, D-type Ikt2, delayed rectifier Ikt3), and a fast sodium current (INa). We demonstrated that Icat1 was required for mediating the plateau potential, unlike INa and Icat2, and its τinactivation determined plateau duration. We also found that Ikt1 dictated plateau potential shape more than Ikt2 and Ikt3. The influence of these two transient and opposing conductances suggests a unique mechanism of plateau potential physiology. PMID:21704681

Fragmented Canopies Control the Regimes of Gravity Current Development

NASA Astrophysics Data System (ADS)

Barcelona, Aina; Serra, Teresa; Colomer, Jordi

2018-03-01

Coastal ecosystems (marine littoral regions, wetlands, and deltas) are regions of high biological productivity. However, they are also one of the world's most threatened ecosystems. Wetlands are characterized by aquatic vegetation adapted to high salinity levels and climatic variations. Wetland canopies buffer these hydrodynamic and atmospheric variations and help retain sediment by reducing current velocity during sea storms or runoff after periods of rain. This work focuses on the effect of the presence of a gap (i.e., nonvegetated zone) parallel to the direction of the main current has on the sedimentation and hydrodynamics of a gravity current. The study aims to (1) address the behavior of a gravity current in a vegetated region compared to one without vegetation (i.e., the gap), (2) determine the effect gap size has on how a gravity current evolves, and 3) determine the effect gap sizes have on the sedimentary rates from a gravity current. Laboratory experiments were carried out in a flume using four different sediment concentrations, four different canopy densities (884, 354, 177, and 0 plants·m-2) and three different gap widths (H/2, H, and 1.5H, where H is the height of the water). This work shows that a gravity current's evolution and its sedimentary rates depend on the fractional volume occupied by the vegetation. While current dynamics in experiments with wider gaps are similar to the nonvegetated case, for smaller gaps the dynamics are closer to the fully vegetated case. Nonetheless, the gravity current exhibits the same behavior in both the vegetated region and the gap.

Associations between iliotibial band injury status and running biomechanics in women.

PubMed

Foch, Eric; Reinbolt, Jeffrey A; Zhang, Songning; Fitzhugh, Eugene C; Milner, Clare E

2015-02-01

Iliotibial band syndrome (ITBS) is a common overuse knee injury that is twice as likely to afflict women compared to men. Lower extremity and trunk biomechanics during running, as well as hip abductor strength and iliotibial band flexibility, are factors believed to be associated with ITBS. The purpose of this cross-sectional study was to determine if differences in lower extremity and trunk biomechanics during running exist among runners with current ITBS, previous ITBS, and controls. Additionally, we sought to determine if isometric hip abductor strength and iliotibial band flexibility were different among groups. Twenty-seven female runners participated in the study. Participants were divided into three equal groups: current ITBS, previous ITBS, and controls. Overground running trials, isometric hip abductor strength, and iliotibial band flexibility were recorded for all participants. Discrete joint and segment biomechanics, as well as hip strength and flexibility measures were analyzed using a one-way analysis of variance. Runners with current ITBS exhibited 1.8 (1.5)° greater trunk ipsilateral flexion and 7 (6)° less iliotibial band flexibility compared to runners with previous ITBS and controls. Runners with previous ITBS exhibited 2.2 (2.9) ° less hip adduction compared to runners with current ITBS and controls. Hip abductor strength 3.3 (2.6) %BM×h was less in runners with previous ITBS but not current ITBS compared to controls. Runners with current ITBS may lean their trunk more towards the stance limb which may be associated with decreased iliotibial band flexibility. Copyright © 2015 Elsevier B.V. All rights reserved.

Determining Energy Saving Behavior and Energy Awareness of Secondary School Students According to Socio-Demographic Characteristics

ERIC Educational Resources Information Center

Aktamis, Hilal

2011-01-01

The aim of this study was to determine energy saving behavior and energy awareness of secondary school students and the effects of socio-demographic characteristics (gender, residential area and grade level) on energy saving and energy awareness. The research is a survey model with an approach that aims to describe the current status. A total of…

Evaluating the Latent Structure of the MMPI-2 F(p) Scale in a Forensic Sample: A Taxometric Analysis

ERIC Educational Resources Information Center

Strong, David R.; Glassmire, David M.; Frederick, Richard I.; Greene, Roger L.

2006-01-01

P. A. Arbisi and Y. S. Ben-Porath (1995) originally proposed that the Infrequency Psychopathology scale, F(p), be used as the final step in an algorithm to determine the validity of a Minnesota Multiphasic Personality Inventory-2 (MMPI-2) protocol. The current study used taxometric procedures to determine the latent structure of F(p) among…

Vocational Education for Youth under the Custody of the Massachusetts Department of Youth Services: Findings and Recommendations. Volume I. Final Report.

ERIC Educational Resources Information Center

Nuttall, Ronald L.; And Others

This study was conducted to accomplish four objectives: (1) determine the current status of vocational education services available to youth under the custody of the Massachusetts Department of Youth Services (DYS); (2) assess the characteristics of DYS youth and their need for additional vocational programs; (3) determine employer and labor union…

Variables Control Charts: A Measurement Tool to Detect Process Problems within Housing

ERIC Educational Resources Information Center

Luna, Andrew

1999-01-01

The purpose of this study was to use quality improvement tools to determine if the current process of supplying hot water to a high-rise residence hall for women at a southeastern Doctoral I granting institution was in control. After a series of focus groups among the residents in the hall, it was determined that they were mostly concerned about…

Evaluation of advanced geopotential models for operational orbit determination

NASA Technical Reports Server (NTRS)

Radomski, M. S.; Davis, B. E.; Samii, M. V.; Engel, C. J.; Doll, C. E.

1988-01-01

To meet future orbit determination accuracy requirements for different NASA projects, analyses are performed using Tracking and Data Relay Satellite System (TDRSS) tracking measurements and orbit determination improvements in areas such as the modeling of the Earth's gravitational field. Current operational requirements are satisfied using the Goddard Earth Model-9 (GEM-9) geopotential model with the harmonic expansion truncated at order and degree 21 (21-by-21). This study evaluates the performance of 36-by-36 geopotential models, such as the GEM-10B and Preliminary Goddard Solution-3117 (PGS-3117) models. The Earth Radiation Budget Satellite (ERBS) and LANDSAT-5 are the spacecraft considered in this study.

NASA/University JOint VEnture (JOVE) Program: Transverse Shear Moduli Using the Torsional Responses of Rectangular Laminates

NASA Technical Reports Server (NTRS)

Bogan, Sam

2001-01-01

The first year included a study of the non-visible damage of composite overwrapped pressure vessels with B. Poe of the Materials Branch of Nasa-Langley. Early determinations showed a clear reduction in non-visible damage for thin COPVs when partially pressurized rather than unpressurized. Literature searches on Thicker-wall COPVs revealed surface damage but clearly visible. Analysis of current Analytic modeling indicated that that current COPV models lacked sufficient thickness corrections to predict impact damage. After a comprehensive study of available published data and numerous numerical studies based on observed data from Langley, the analytic framework for modeling the behavior was determined lacking and both Poe and Bogan suggested any short term (3yr) result for Jove would be overly ambitious and emphasis should be placed on transverse shear moduli studies. Transverse shear moduli determination is relevant to the study of fatigue, fracture and aging effects in composite structures. Based on the techniques developed by Daniel & Tsai, Bogan and Gates determined to verify the results for K3B and 8320. A detailed analytic and experimental plan was established and carried out that included variations in layup, width, thickness, and length. As well as loading rate variations to determine effects and relaxation moduli. The additional axial loads during the torsion testing were studied as was the placement of gages along the composite specimen. Of the proposed tasks, all of tasks I and 2 were completed with presentations given at Langley, SEM conferences and ASME/AIAA conferences. Sensitivity issues with the technique associated with the use of servohydraulic test systems for applying the torsional load to the composite specimen limited the torsion range for predictable and repeatable transverse shear properties. Bogan and Gates determined to diverge on research efforts with Gates continuing the experimental testing at Langley and Bogan modeling the apparent non-linear behavior at low torque & angles apparent from the tests.

Novel plasma source for safe beryllium spectral line studies in the presence of beryllium dust

NASA Astrophysics Data System (ADS)

Stankov, B. D.; Vinić, M.; Gavrilović Božović, M. R.; Ivković, M.

2018-05-01

Plasma source for beryllium spectral line studies in the presence of beryllium dust particles was realised. The guideline during construction was to prevent exposure to formed dust, considering the toxicity of beryllium. Plasma source characterization through determination of optimal working conditions is described. The necessary conditions for Be spectral line appearance and optimal conditions for line shape measurements are found. It is proven experimentally that under these conditions dust appears coincidently with the second current maximum. The electron density measured after discharge current maximum is determined from the peak separation of the hydrogen Balmer beta spectral line, and the electron temperature is determined from the ratios of the relative intensities of Be spectral lines emitted from successive ionized stages of atoms. Maximum values of electron density and temperature are measured to be 9.3 × 1022 m-3 and 16 800 K, respectively. Construction details and testing of the BeO discharge tube in comparison with SiO2 and Al2O3 discharge tubes are also presented in this paper.

TU-EF-204-09: A Preliminary Method of Risk-Informed Optimization of Tube Current Modulation for Dose Reduction in CT

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

Gao, Y; Liu, B; Kalra, M

Purpose: X-rays from CT scans can increase cancer risk to patients. Lifetime Attributable Risk of Cancer Incidence for adult patients has been investigated and shown to decrease as patient age. However, a new risk model shows an increasing risk trend for several radiosensitive organs for middle age patients. This study investigates the feasibility of a general method for optimizing tube current modulation (TCM) functions to minimize risk by reducing radiation dose to radiosensitive organs of patients. Methods: Organ-based TCM has been investigated in literature for eye lens dose and breast dose. Adopting the concept in organ-based TCM, this study seeksmore » to find an optimized tube current for minimal total risk to breasts and lungs by reducing dose to these organs. The contributions of each CT view to organ dose are determined through simulations of CT scan view-by-view using a GPU-based fast Monte Carlo code, ARCHER. A Linear Programming problem is established for tube current optimization, with Monte Carlo results as weighting factors at each view. A pre-determined dose is used as upper dose boundary, and tube current of each view is optimized to minimize the total risk. Results: An optimized tube current is found to minimize the total risk of lungs and breasts: compared to fixed current, the risk is reduced by 13%, with breast dose reduced by 38% and lung dose reduced by 7%. The average tube current is maintained during optimization to maintain image quality. In addition, dose to other organs in chest region is slightly affected, with relative change in dose smaller than 10%. Conclusion: Optimized tube current plans can be generated to minimize cancer risk to lungs and breasts while maintaining image quality. In the future, various risk models and greater number of projections per rotation will be simulated on phantoms of different gender and age. National Institutes of Health R01EB015478.« less

Thin current sheets observation by MMS during a near-Earth's magnetotail reconnection event

NASA Astrophysics Data System (ADS)

Nakamura, R.; Varsani, A.; Nakamura, T.; Genestreti, K.; Plaschke, F.; Baumjohann, W.; Nagai, T.; Burch, J.; Cohen, I. J.; Ergun, R.; Fuselier, S. A.; Giles, B. L.; Le Contel, O.; Lindqvist, P. A.; Magnes, W.; Schwartz, S. J.; Strangeway, R. J.; Torbert, R. B.

2017-12-01

During summer 2017, the four spacecraft of the Magnetospheric Multiscale (MMS) mission traversed the nightside magnetotail current sheet at an apogee of 25 RE. They detected a number of flow reversal events suggestive of the passage of the reconnection current sheet. Due to the mission's unprecedented high-time resolution and spatial separation well below the ion scales, structure of thin current sheets is well resolved both with plasma and field measurements. In this study we examine the detailed structure of thin current sheets during a flow reversal event from tailward flow to Earthward flow, when MMS crossed the center of the current sheet . We investigate the changes in the structure of the thin current sheet relative to the X-point based on multi-point analysis. We determine the motion and strength of the current sheet from curlometer calculations comparing these with currents obtained from the particle data. The observed structures of these current sheets are also compared with simulations.

DEEP WATER ISOTOPIC CURRENT ANALYZER

DOEpatents

Johnston, W.H.

1964-04-21

A deepwater isotopic current analyzer, which employs radioactive isotopes for measurement of ocean currents at various levels beneath the sea, is described. The apparatus, which can determine the direction and velocity of liquid currents, comprises a shaft having a plurality of radiation detectors extending equidistant radially therefrom, means for releasing radioactive isotopes from the shaft, and means for determining the time required for the isotope to reach a particular detector. (AEC)

Administrative Coaching Practices: Content, Personalization, and Support

ERIC Educational Resources Information Center

Hayashi, Christine A.

2016-01-01

This study surveys educators who have completed, or are in their second year of, an administrative coaching program that results in a California Clear Administrative Credential, also known as Tier II. The purpose of the study is to determine the perceptions of these educators regarding whether current practices in administrative coaching programs…

The Role of Illustrations in Children's Inferential Comprehension

ERIC Educational Resources Information Center

Pike, Meredith M.; Barnes, Marcia A.; Barron, Roderick W.

2010-01-01

Illustrations are a salient source of information in children's books, yet their effect on children's reading comprehension has been studied only through literal factual recall. The purpose of the current study was to determine the effect of illustrations on bridging inferences, an important aspect of meaning making in comprehension models.…

Biology Student Teachers' Cognitive Structure about "Living Thing"

ERIC Educational Resources Information Center

Kurt, Hakan

2013-01-01

The current study aims to determine biology student teachers' cognitive structure on the concept of "living thing" through revealing their conceptual framework. Qualitative research method was applied in this study. The data were collected from 44 biology student teachers. A free word association test was used as a data collection…

Preferences and Experiences of Traditional and Nontraditional University Students

ERIC Educational Resources Information Center

Woods, Kathryn; Frogge, George

2017-01-01

This study compared and contrasted preferences and experiences of traditional and nontraditional students. Students at a midsized state university in the southeast region of the United States were surveyed to determine the number of hours spent working off campus, hours spent studying, their preferred learning format, and current grade point…

Indicators of Dysphagia in Aged Care Facilities

ERIC Educational Resources Information Center

Pu, Dai; Murry, Thomas; Wong, May C. M.; Yiu, Edwin M. L.; Chan, Karen M. K.

2017-01-01

Purpose: The current cross-sectional study aimed to investigate risk factors for dysphagia in elderly individuals in aged care facilities. Method: A total of 878 individuals from 42 aged care facilities were recruited for this study. The dependent outcome was speech therapist-determined swallowing function. Independent factors were Eating…

Vietnam Revised: Are Our Textbooks Changing?

ERIC Educational Resources Information Center

Fleming, Dan B.; Nurse, Ronald J.

1982-01-01

Describes a study which analyzed 10 current and widely used secondary U.S. history textbooks for their coverage of the Vietnam War to determine their accuracy, completeness, and objectivity. Most of the textbooks studied offered a too sketchy account of the Vietnam War. Certain key topics are often neglected. (RM)

Psychological and Social Predictors of Suicidal Ideation among Young Adolescents

ERIC Educational Resources Information Center

Kirkcaldy, Bruce D.; Eysenck, Michael W.; Siefen, Georg R.

2004-01-01

Although there is an enormous amount of literature demonstrating socio-psychological determinants of suicide and self-injurious behaviour among adults or clinical samples of children and adolescents, there is a scarcity of studies focussing on non-clinical adolescent samples. The current study examined associations between self-reported data on…

School Nurses' Knowledge of Autism Spectrum Disorders

ERIC Educational Resources Information Center

Strunk, Julie A.

2009-01-01

The purpose of this study was to determine school nurses' working knowledge of autism spectrum disorders (ASDs). The current knowledge of school nurses was investigated by means of a mixed-method exploratory descriptive pilot study. Instrumentation included a scale that measured the knowledge of school nurses in regard to ASD, including medication…

Biomarker Utility Analysis Using an Exposure-PBPK/PD Model: A Carbaryl Case Study

EPA Science Inventory

There are two common biomarkers: markers of exposure and markers of health effects. The strength of the correlation between exposure or effect and a biomarker measurement determines the utility of a biomarker for assessing exposures or risks. In the current study, a linked expo...

Religion, Ethnicity and Language Learning Strategies

ERIC Educational Resources Information Center

Liyanage, Indika; Birch, Gary; Grimbeek, Peter

2004-01-01

Previous studies (Liyanage, 2003a, 2003b, 2004) by one of the authors indicated that ethnicity and religion jointly predict the metacognitive, cognitive and social affective strategies of ESL learners in Sri Lanka. The current study further examines which of these two variables (ethnicity or religion) is more important in determining the…

A Feasibility Study of Providing Regional Data Processing Services.

ERIC Educational Resources Information Center

Nelson, Norbert J.; And Others

A Title III ESEA study sought to determine the feasibility of establishing a central data processing service by the Wabash Valley Education Center for its member schools. First, current applications of data processing in education were reviewed to acquire detailed specifications for an educational data processing center's hardware, software, and…

Current and past menstrual status is an important determinant of femoral neck geometry in exercising women.

PubMed

Mallinson, Rebecca J; Williams, Nancy I; Gibbs, Jenna C; Koehler, Karsten; Allaway, Heather C M; Southmayd, Emily; De Souza, Mary Jane

2016-07-01

Menstrual status, both past and current, has been established as an important determinant of bone mineral density (BMD) in young exercising women. However, little is known regarding the association between the cumulative effect of menstrual status and indices of bone health beyond BMD, such as bone geometry and estimated bone strength. This study explores the association between cumulative menstrual status and indices of bone health assessed using dual-energy x-ray absorptiometry (DXA), including femoral neck geometry and strength and areal BMD (aBMD), in exercising women. 101 exercising women (22.0±0.4years, BMI 21.0±0.2kg/m(2), 520±40min/week of self-reported exercise) participated in this cross-sectional study. Women were divided into three groups as follows based on their self-reported current and past menstrual status: 1) current and past regular menstrual cycles (C+P-R) (n=23), 2) current and past irregular menstrual cycles (C+P-IR) (n=56), 3) and current or past irregular cycles (C/P-RIR) (n=22). Current menstrual status was confirmed using daily urinary metabolites of reproductive hormones. DXA was used to assess estimates of femoral neck geometry and strength from hip strength analysis (HSA), aBMD, and body composition. Cross-sectional moment of inertia (CSMI), cross-sectional area (CSA), strength index (SI), diameter, and section modulus (Z) were calculated at the femoral neck. Low CSMI, CSA, SI, diameter, and Z were operationally defined as values below the median. Areal BMD (g/cm(2)) and Z-scores were determined at the lumbar spine, femoral neck, and total hip. Low BMD was defined as a Z-score<-1.0. Chi-square tests and multivariable logistic regression were performed to compare the prevalence and determine the odds, respectively, of low bone geometry, strength, and aBMD among groups. Cumulative menstrual status was identified as a significant predictor of low femoral neck CSMI (p=0.005), CSA (p≤0.024), and diameter (p=0.042) after controlling for confounding variables. C+P-IR or C/P-RIR were four to eight times more likely to exhibit low femoral neck CSMI or CSA when compared with C+P-R. Lumbar spine aBMD and Z-score were lower in C+P-IR when compared with C+P-R (p≤0.003). A significant association between menstrual group and low aBMD was observed at the lumbar spine (p=0.006) but not at the femoral neck or total hip (p>0.05). However, after controlling for confounding variables, cumulative menstrual status was not a significant predictor of low aBMD. In exercising women, the cumulative effect of current and past menstrual irregularity appears to be an important predictor of lower estimates of femoral neck geometry, as observed by smaller CSMI and CSA, which may serve as an another means, beyond BMD, by which menstrual irregularity compromises bone strength. As such, evaluation of both current and past menstrual status is recommended to determine potential risk for relatively small bone geometry at the femoral neck. Copyright © 2016 Elsevier Inc. All rights reserved.

Theoretical model of gravitational perturbation of current collector axisymmetric flow field

NASA Astrophysics Data System (ADS)

Walker, John S.; Brown, Samuel H.; Sondergaard, Neal A.

1989-03-01

Some designs of liquid metal collectors in homopolar motors and generators are essentially rotating liquid metal fluids in cylindrical channels with free surfaces and will, at critical rotational speeds, become unstable. The role of gravity in modifying this ejection instability is investigated. Some gravitational effects can be theoretically treated by perturbation techniques on the axisymmetric base flow of the liquid metal. This leads to a modification of previously calculated critical current collector ejection values neglecting gravity effects. The derivation of the mathematical model which determines the perturbation of the liquid metal base flow due to gravitational effects is documented. Since gravity is a small force compared with the centrifugal effects, the base flow solutions can be expanded in inverse powers of the Froude number and modified liquid flow profiles can be determined as a function of the azimuthal angle. This model will be used in later work to theoretically study the effects of gravity on the ejection point of the current collector. A rederivation of the hydrodynamic instability threshold of a liquid metal current collector is presented.

Laboratory-based geoelectric monitoring of water infiltration in consolidated ground

NASA Astrophysics Data System (ADS)

Yang, Lining; Sun, Qiang; Yang, Haiping

2018-04-01

Infiltration usually plays a significant role in construction failures and transfer of contaminants. Therefore, it is very important to monitor underground water migration. In this study, a soil infiltration experiment was carried out using an indoor model test. The water infiltration characteristics were recorded and analyzed based on the response of the geoelectric field, including the primary field potential, self-potential, excitation current and apparent resistivity. The phreatic water surface and the infiltration velocity were determined. The inversion results were compared with direct observations. The results showed that the changes in the geoelectric field parameters explain the principles of groundwater flow. The infiltration velocity and the phreatic surface can be determined based on the primary field potential response and the excitation current. When the phreatic surface reached the location of the electrodes, the primary field potential and self-potential decreased rapidly whereas the excitation current increased rapidly. The height of the phreatic surface and the infiltration time exhibited a linear relationship for both the observation data and the calculations of the excitation current. The apparent resistivity described the infiltration status in the soil and tracked the phreatic surface accurately.

Theoretical model of gravitational perturbation of current collector axisymmetric flow field

NASA Astrophysics Data System (ADS)

Walker, John S.; Brown, Samuel H.; Sondergaard, Neal A.

1990-05-01

Some designs of liquid-metal current collectors in homopolar motors and generators are essentially rotating liquid-metal fluids in cylindrical channels with free surfaces and will, at critical rotational speeds, become unstable. An investigation at David Taylor Research Center is being performed to understand the role of gravity in modifying this ejection instability. Some gravitational effects can be theoretically treated by perturbation techniques on the axisymmetric base flow of the liquid metal. This leads to a modification of previously calculated critical-current-collector ejection values neglecting gravity effects. The purpose of this paper is to document the derivation of the mathematical model which determines the perturbation of the liquid-metal base flow due to gravitational effects. Since gravity is a small force compared with the centrifugal effects, the base flow solutions can be expanded in inverse powers of the Froude number and modified liquid-flow profiles can be determined as a function of the azimuthal angle. This model will be used in later work to theoretically study the effects of gravity on the ejection point of the current collector.

Welding current and melting rate in GMAW of aluminium

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

Pandey, S.; Rao, U.R.K.; Aghakhani, M.

1996-12-31

Studies on GMAW of aluminium and its alloy 5083, revealed that the welding current and melting rate were affected by any change in wire feed rate, arc voltage, nozzle to plate distance, welding speed and torch angle. Empirical models have been presented to determine accurately the welding current and melting rate for any set of these parameters. These results can be utilized for determining accurately the heat input into the workpiece from which reliable predictions can be made about the mechanical and the metallurgical properties of a welded joint. The analysis of the model also helps in providing a vitalmore » information about the static V-I characteristics of the welding power source. The models were developed using a two-level fractional factorial design. The adequacy of the model was tested by the use of analysis of variance technique and the significance of the coefficients was tested by the student`s t test. The estimated and observed values of the welding current and melting rate have been shown on a scatter diagram and the interaction effects of different parameters involved have been presented in graphical forms.« less

7 CFR 1956.66 - Compromise and adjustment of nonjudgment debts.

Code of Federal Regulations, 2010 CFR

2010-01-01

... be retained by the debtor if the debtor offers an amount at least equal to the current fair market... in the debtor's file. (ii) Value of existing security as determined by a current appraisal made or... 103-354 determines the debtor can pay based on a current financial statement and other information...

Design of piles for integral abutment bridges.

DOT National Transportation Integrated Search

1984-08-01

More and more, integral abutment bridges are being used in place : of the more traditional bridge designs with expansion releases. In : this study, states which use integral abutment bridges were surveyed : to determine their current practice in the ...

CHLORINE DISINFECTION OF AEROMONAS

EPA Science Inventory

The bacterial genus Aeromonas is currently listed on the USEPA's Candidate Contaminant List (CCL). Resistance to chemical disinfection is an essential aspect regarding all microbial groups listed on the CCL. This study was designed to determine the inactivation kinetics of Aeromo...

MERCURY IN AN INSECTIVOROUS BIRD SPECIES

EPA Science Inventory

Mercury distributions within ecosystems must be examined to determine exposure and risk to wildlife in specific areas. In the current study, we examined exposure and uptake of mercury in nestling prothonotary warblers (protonitaria citrea) inhabiting two National Priority List (...

Validation and Continued Development of Methods for Spheromak Simulation

NASA Astrophysics Data System (ADS)

Benedett, Thomas

2017-10-01

The HIT-SI experiment has demonstrated stable sustainment of spheromaks. Determining how the underlying physics extrapolate to larger, higher-temperature regimes is of prime importance in determining the viability of the inductively-driven spheromak. It is thus prudent to develop and validate a computational model that can be used to study current results and study the effect of possible design choices on plasma behavior. An extended MHD model has shown good agreement with experimental data at 14 kHz injector operation. Efforts to extend the existing validation to a range of higher frequencies (36, 53, 68 kHz) using the PSI-Tet 3D extended MHD code will be presented, along with simulations of potential combinations of flux conserver features and helicity injector configurations and their impact on current drive performance, density control, and temperature for future SIHI experiments. Work supported by USDoE.

Glycobiology of Reproductive Processes in Marine Animals: The State of the Art

PubMed Central

Gallo, Alessandra; Costantini, Maria

2012-01-01

Glycobiology is the study of complex carbohydrates in biological systems and represents a developing field of science that has made huge advances in the last half century. In fact, it combines all branches of biomedical research, revealing the vast and diverse forms of carbohydrate structures that exist in nature. Advances in structure determination have enabled scientists to study the function of complex carbohydrates in more depth and to determine the role that they play in a wide range of biological processes. Glycobiology research in marine systems has primarily focused on reproduction, in particular for what concern the chemical communication between the gametes. The current status of marine glycobiology is primarily descriptive, devoted to characterizing marine glycoconjugates with potential biomedical and biotechnological applications. In this review, we describe the current status of the glycobiology in the reproductive processes from gametogenesis to fertilization and embryo development of marine animals. PMID:23247316

A simulator study for the development and evaluation of operating procedures on a supersonic cruise research transport to minimize airport-community noise

NASA Technical Reports Server (NTRS)

Grantham, W. D.; Smith, P. M.; Deal, P. L.

1980-01-01

Piloted-simulator studies were conducted to determine takeoff and landing operating procedures for a supersonic cruise research transport concept that result in predicted noise levels which meet current Federal Aviation Administration (FAA) certification standards. With the use of standard FAA noise certification test procedures, the subject simulated aircraft did not meet the FAA traded-noise-level standards during takeoff and landing. However, with the use of advanced procedures, this aircraft meets the traded-noise-level standards for flight crews with average skills. The advanced takeoff procedures developed involved violating some of the current Federal Aviation Regulations (FAR), but it was not necessary to violate any FAR noise-test conditions during landing approach. Noise contours were also determined for some of the simulated takeoffs and landings in order to indicate the noise-reduction advantages of using operational procedures other than standard.

Certain physical properties of cobalt and nickel borides

NASA Technical Reports Server (NTRS)

Kostetskiy, I. I.; Lvov, S. N.

1981-01-01

The temperature dependence of the electrical resistivity, the thermal conductivity, and the thermal emf of cobalt and nickel borides were studied. In the case of the nickel borides the magnetic susceptibility and the Hall coefficient were determined at room temperature. The results are discussed with allowance for the current carrier concentration, the effect of various mechanisms of current-carrier scattering and the location of the Fermi level in relation to the 3d band.

Trinity Bay Study: Dye tracing experiments

NASA Technical Reports Server (NTRS)

Ward, G. H., Jr.

1972-01-01

An analysis of the heat balance and temperature distribution within Trinity Bay near Galveston, Texas is presented. The effects of tidal currents, wind driven circulations, and large volume inflows are examined. Emphasis is placed on the effects of turbulent diffusion and local shears in currents. The technique of dye tracing to determine the parameters characterizing dispersion is described. Aerial photographs and maps are provided to show the flow conditions existing at different times and seasons.

ST5 Observations of the Imbalance of Region 1 and 2 Field-Aligned Currents and its Implication to Ionospheric Closure Currents

NASA Technical Reports Server (NTRS)

Le, G.

2008-01-01

A major unsolved question in the physics of ionosphere-magnetosphere coupling is how field-aligned currents (FACs) close. In order to maintain the divergence free condition, overall downward FACs (carried mainly by upward electrons) must eventually balance the overall upward FACs associated with the precipitating electrons through ionospheric Pedersen currents. Although much of the current closure may take place via local Pedersen currents flowing between Region 1 (R1) and Region 2 (R2) FACs, there is a generally an imbalance, i.e., more currents in R1 than in R2, in total currents between them. The net currents may be closed within R1 via cross-polar cap Pedersen currents. In this study, we use the magnetic field observations from Space Technology 5 mission to quantify the imbalance of R1 and R2 currents. We will determine the net R1-R2 currents under various solar wind conditions and discuss the implication of such imbalance to the ionospheric closure currents.

Determinants of exposure to second-hand tobacco smoke (SHS) among current non-smoking in-school adolescents (aged 11-18 years) in South Africa: results from the 2008 GYTS study.

PubMed

Peltzer, Karl

2011-09-01

The aim of this study was to estimate the prevalence and identify correlates of second-hand tobacco smoke (SHS) among 6,412 current non-smoking school-going adolescents (aged 11 to 18 years) in South Africa. A cross-sectional study was carried out in 2008 in South Africa within the framework of the Global Youth Tobacco Survey. Overall, 25.7% of students were exposed to SHS at home, 34.2% outside of the home and 18.3% were exposed to SHS at home and outside of the home. Parental and close friends smoking status, allowing someone to smoke around you and perception that passive smoking was harmful were significant determinants of adolescent's exposure to both SHS at home and outside of the home. Identified factors can inform the implementation of public health interventions in order to reduce passive smoking among adolescents.

The Pliocene to recent history of the Kuroshio and Tsushima Currents: a multi-proxy approach

NASA Astrophysics Data System (ADS)

Gallagher, Stephen J.; Kitamura, Akihisa; Iryu, Yasufumi; Itaki, Takuya; Koizumi, Itaru; Hoiles, Peter W.

2015-12-01

The Kuroshio Current is a major western boundary current controlled by the North Pacific Gyre. It brings warm subtropical waters from the Indo-Pacific Warm Pool to Japan exerting a major control on Asian climate. The Tsushima Current is a Kuroshio offshoot transporting warm water into the Japan Sea. Various proxies are used to determine the paleohistory of these currents. Sedimentological proxies such as reefs, bedforms, sediment source and sorting reveal paleocurrent strength and latitude. Proxies such as coral and mollusc assemblages reveal past shelfal current activity. Microfossil assemblages and organic/inorganic geochemical analyses determine paleo- sea surface temperature and salinity histories. Transportation of tropical palynomorphs and migrations of Indo-Pacific species to Japanese waters also reveal paleocurrent activity. The stratigraphic distribution of these proxies suggests the Kuroshio Current reached its present latitude (35 °N) by ~3 Ma when temperatures were 1 to 2 °C lower than present. At this time a weak Tsushima Current broke through Tsushima Strait entering the Japan Sea. Similar oceanic conditions persisted until ~2 Ma when crustal stretching deepened the Tsushima Strait allowing inflow during every interglacial. The onset of stronger interglacial/glacial cycles ~1 Ma was associated with increased North Pacific Gyre and Kuroshio Current intensity. This triggered Ryukyu Reef expansion when reefs reached their present latitude (~31 °N), thereafter the reef front advanced (~31 °N) and retreated (~25 °N) with each cycle. Foraminiferal proxy data suggests eastward deflection of the Kuroshio Current from its present path at 24 °N into the Pacific Ocean due to East Taiwan Channel restriction during the Last Glacial Maximum. Subsequently Kuroshio flow resumed its present trajectory during the Holocene. Ocean modeling and geochemical proxies show that the Kuroshio Current path may have been similar during glacials and interglacials, however the glacial mode of this current remains controversial. Paleohistorical studies form important analogues for current behavior with future climate change, however, there are insufficient studies at present in the region that may be used for this purpose. Modeling of the response of the Kuroshio Current to future global warming reveals that current velocity may increase by up to 0.3 m/sec associated with a northward migration of the Kuroshio Extension.

Treatment of depression in low-level residential care facilities for the elderly.

PubMed

George, Kuruvilla; Davison, Tanya E; McCabe, Marita; Mellor, David; Moore, Kathleen

2007-12-01

The rate of recognition and treatment of depressed older people in nursing homes is low. Data from the low-level residential care population have not been reported. This study aimed to collect information about the treatment of depression among older persons living in low-level residential care (hostels). The participants comprised 300 elderly residents from ten low-level residential care facilities from various suburbs in metropolitan Melbourne. The participants were interviewed by a trained clinical psychologist to determine the presence or absence of major or minor depressive disorder using the Structured Clinical Interview for DSM-IV Axis I Disorder (SCID-I). Each participant was also administered the Standardized Mini-mental State Examination (SMMSE) to determine level of cognitive function. The clinical psychologist then reviewed all cases in consultation with a geropsychiatrist experienced in the diagnosis of depression among older people, prior to assigning a diagnosis of depression. An important finding in this study was the low treatment for currently depressed residents, with less than half of those in the sample who were depressed receiving treatment. However, 61 of the 96 residents out of the sample of 300 who were on antidepressants were not currently depressed. There is an under recognition and under treatment of currently depressed older people in low-level residential care facilities (hostels) just as has been reported in studies in nursing homes. However, there are high numbers receiving antidepressants who are not currently depressed.

The Studies of a Vacuum Gap Breakdown after High-Current Arc Interruption with Increasing the Voltage

NASA Astrophysics Data System (ADS)

Schneider, A. V.; Popov, S. A.; Batrakov, A. V.; Dubrovskaya, E. L.; Lavrinovich, V. A.

2017-12-01

Vacuum-gap breakdown has been studied after high-current arc interruption with a subsequent increase in the transient recovery voltage across a gap. The effects of factors, such as the rate of the rise in the transient voltage, the potential of the shield that surrounds a discharge gap, and the arc burning time, have been determined. It has been revealed that opening the contacts earlier leads to the formation of an anode spot, which is the source of electrode material vapors into the discharge gap after current zero moment. Under the conditions of increasing voltage, this fact results in the breakdown. Too late opening leads to the breakdown of a short gap due to the high electric fields.

Parametric study of power absorption from electromagnetic waves by small ferrite spheres

NASA Technical Reports Server (NTRS)

Englert, Gerald W.

1989-01-01

Algebraic expressions in terms of elementary mathematical functions are derived for power absorption and dissipation by eddy currents and magnetic hysteresis in ferrite spheres. Skin depth is determined by using a variable inner radius in descriptive integral equations. Numerical results are presented for sphere diameters less than one wavelength. A generalized power absorption parameter for both eddy currents and hysteresis is expressed in terms of the independent parameters involving wave frequency, sphere radius, resistivity, and complex permeability. In general, the hysteresis phenomenon has a greater sensitivity to these independent parameters than do eddy currents over the ranges of independent parameters studied herein. Working curves are presented for obtaining power losses from input to the independent parameters.

Curriculum leadership in the postgraduate: Gap between current and optimal status.

PubMed

Avizhgan, Maryam; Jafari, Ebrahim Mirshah; Nasr, Ahmad Reza; Changiz, Tahereh

2015-04-01

Identifying the strengths and weakness points is one of the effective methods to analyze current status, and prioritizing actions based on the gap between current and optimal status is necessary for short-term and long-term planning in departments and colleges. The aim of this study was to determine the gap between current and optimal status of curriculum leadership in the postgraduate courses in two Iranian universities. In this cross-sectional study, a sample of 212 faculty members from the two Iranian universities (one medical and one nonmedical) was randomly selected through stratified random sampling method. Data were collected by using a researcher-made questionnaire, with 55 items categorized in four areas of main dimensions in curriculum leadership. The validity of the questionnaire was determined by curriculum studies scholars, and the reliability was confirmed as the Cronbach's alpha calculated 0.969. Data were analyzed using descriptive and inferential statistics according to the variables. There was a gap in all dimensions and roles. The maximum gap (-1.70) with the highest frequency (98%) were related to "improving the educational atmosphere" dimension. As for items, the maximum gap (-2.41) was related to "society needs and expectations and the labor market" in "curriculum development and revision" dimension. The negative gap between all dimensions of curriculum leadership implies faculty members' dissatisfaction. Curriculum leadership at universities, colleges and departments of the study in all aspects need to be improved. Hence, it is necessary for managers to make use of the viewpoints of the faculty members to decrease the gap.

Curriculum leadership in the postgraduate: Gap between current and optimal status

PubMed Central

Avizhgan, Maryam; Jafari, Ebrahim Mirshah; Nasr, Ahmad Reza; Changiz, Tahereh

2015-01-01

Background: Identifying the strengths and weakness points is one of the effective methods to analyze current status, and prioritizing actions based on the gap between current and optimal status is necessary for short-term and long-term planning in departments and colleges. The aim of this study was to determine the gap between current and optimal status of curriculum leadership in the postgraduate courses in two Iranian universities. Materials and Methods: In this cross-sectional study, a sample of 212 faculty members from the two Iranian universities (one medical and one nonmedical) was randomly selected through stratified random sampling method. Data were collected by using a researcher-made questionnaire, with 55 items categorized in four areas of main dimensions in curriculum leadership. The validity of the questionnaire was determined by curriculum studies scholars, and the reliability was confirmed as the Cronbach's alpha calculated 0.969. Data were analyzed using descriptive and inferential statistics according to the variables. Results: There was a gap in all dimensions and roles. The maximum gap (−1.70) with the highest frequency (98%) were related to “improving the educational atmosphere” dimension. As for items, the maximum gap (−2.41) was related to “society needs and expectations and the labor market” in “curriculum development and revision” dimension. Conclusion: The negative gap between all dimensions of curriculum leadership implies faculty members’ dissatisfaction. Curriculum leadership at universities, colleges and departments of the study in all aspects need to be improved. Hence, it is necessary for managers to make use of the viewpoints of the faculty members to decrease the gap. PMID:26109996

Prevalence and Correlates of Internet Addiction in Undergraduate Students as Assessed by Two Different Measures

ERIC Educational Resources Information Center

Schoenfeld, Daniel

2011-01-01

The current study addressed some of the methodological shortcomings of previous studies on internet addiction. The main purpose of the study was to determine if two different internet addiction assessments would identify the same individuals as addicted to the internet. A total of 224 undergraduate internet users were surveyed using a stratified…

Financial Leadership Competencies for Public College and University Presidential Leaders in Georgia: A Delphi Study

ERIC Educational Resources Information Center

Jones, Susan M.

2011-01-01

The purpose of the mixed-method Delphi study is to identify the financial leadership competencies considered most important in operating public higher education institutions. The current study also determined whether differences existed in the perceptions of participants' age, level of education, years of service as a president, the number of…

Information Technologies Pre-Service Teachers' Acceptance of Tablet PCs as an Innovative Learning Tool

ERIC Educational Resources Information Center

Cuhadar, Cem

2014-01-01

The current study is aimed to determine if Turkish IT pre-service teachers' acceptance of tablet PCs is within the framework of the Technology Acceptance Model. The research was patterned as a phenomenological study which is among the qualitative research methods. Participants were eight pre-service teachers studying in Trakya University, Faculty…

Effectiveness of Computer-Assisted Mathematics Education (CAME) over Academic Achievement: A Meta-Analysis Study

ERIC Educational Resources Information Center

Demir, Seda; Basol, Gülsah

2014-01-01

The aim of the current study is to determine the overall effects of Computer-Assisted Mathematics Education (CAME) on academic achievement. After an extensive review of the literature, studies using Turkish samples and observing the effects of Computer-Assisted Education (CAE) on mathematics achievement were examined. As a result of this…

Hydrodynamics of a Multistage Wet Scrubber Incineration Conditions

ERIC Educational Resources Information Center

Said, M. M.; Manyele, S. V.; Raphael, M. L.

2012-01-01

The objective of the study was to determine the hydrodynamics of the two stage counter-current cascade wet scrubbers used during incineration of medical waste. The dependence of the hydrodynamics on two main variables was studied: Inlet air flow rate and inlet liquid flow rate. This study introduces a new wet scrubber operating features, which are…

Perceived determinants of cardiovascular risk management in primary care: disconnections between patient behaviours, practice organisation and healthcare system.

PubMed

Huntink, E; Wensing, M; Klomp, M A; van Lieshout, J

2015-12-15

Although conditions for high quality cardiovascular risk management in primary care in the Netherlands are favourable, there still remains a gap between practice guideline recommendations and practice. The aim of the current study was to identify determinants of cardiovascular primary care in the Netherlands. We performed a qualitative study, using semi-structured interviews with healthcare professionals and patients with established cardiovascular diseases or at high cardiovascular risk. A framework analysis was used to cluster the determinants into seven domains: 1) guideline factors, 2) individual healthcare professional factors, 3) patient factors, 4) professional interaction, 5) incentives and recourses, 6) mandate, authority and accountability, and 7) social, political and legal factors. Twelve healthcare professionals and 16 patients were interviewed. Healthcare professionals and patients mentioned a variety of factors concerning all seven domains. Determinants of practice according to the health care professionals were related to communication between healthcare professionals, patients' lack of knowledge and self-management, time management, market mechanisms in the Dutch healthcare system and motivational interviewing skills of healthcare professionals. Patients mentioned determinants related to their knowledge of risk factors for cardiovascular diseases, medication adherence and self-management as key determinants. A key finding is the mismatch between healthcare professionals' and patients' views on patient's knowledge and self-management. Perceived determinants of cardiovascular risk management were mainly related to patient behaviors and (but only for health professionals) to the healthcare system. Though health care professionals and patients agree upon the importance of patients' knowledge and self-management, their judgment of the current state of knowledge and self-management is entirely different.

Current Mexican-American and Chicano Studies Undergraduate College Programs in the United States.

ERIC Educational Resources Information Center

Jaramillo, James A.

This study conducted a library literature search of college guides, directories, and catalogs to determine the number of undergraduate level Chicano/a Studies and Mexican-American Studies programs in the U.S. The analysis found that there were 76 undergraduate programs in these fields, including 20 at two-year colleges and 56 at four-year…

The Relationship of Field of Study to Current Smoking Status among College Students

ERIC Educational Resources Information Center

Berg, Carla J.; Klatt, Colleen M.; Thomas, Janet L.; Ahluwalia, Jasjit S.; An, Lawrence C.

2009-01-01

Problem: No research to date has examined smoking rates among the different fields of study and smoking among college students. Thus, this study aimed to determine if smoking prevalence vary among students in the different fields of study. Method: An online health behavior survey was administered to 25,000 students (n=6,492; 26% response rate).…

1983 Home Study Survey. A Report on Current Course Structure and Educational Practices in NHSC Member Institutions.

ERIC Educational Resources Information Center

National Home Study Council, Washington, DC.

A study examined the course structure and educational practices used by National Home Study Council (NHSC) member institutions. To gather data for the study, researchers mailed questionnaires to 60 members of the NHSC. Based on data from the 51 usable responses, the researchers determined that the average age of students enrolled in programs…

Electronic Properties of Grain Boundaries in GaAs: A Study of Oriented Bicrystals Prepared by Epitaxial Lateral Overgrowth.

DTIC Science & Technology

1984-05-10

overgrowth from a spoke 90 pattern of radial stripe openings at 1 intervals on an Si0 2 coated (110) surface. Bright regions are GaAs and dark regions are Si0...the dark current for such an ideal device is given by Idark - Io[exp(eVbi/AokT) - 1] , (11-l) where Io is a proportionality constant describing the...recombination and leakage currents which contribute to an increased dark current. The value of Voc is determined by the built-in junction barrier height and the

Measurement of Charged and Neutral Current e-p Deep Inelastic Scattering Cross Sections at High Q2

NASA Astrophysics Data System (ADS)

Derrick, M.; Krakauer, D.; Magill, S.; Mikunas, D.; Musgrave, B.; Repond, J.; Stanek, R.; Talaga, R. L.; Zhang, H.; Ayad, R.; Bari, G.; Basile, M.; Bellagamba, L.; Boscherini, D.; Bruni, A.; Bruni, G.; Bruni, P.; Cara Romeo, G.; Castellini, G.; Chiarini, M.; Cifarelli, L.; Cindolo, F.; Contin, A.; Corradi, M.; Gialas, I.; Giusti, P.; Iacobucci, G.; Laurenti, G.; Levi, G.; Margotti, A.; Massam, T.; Nania, R.; Nemoz, C.; Palmonari, F.; Polini, A.; Sartorelli, G.; Timellini, R.; Zamora Garcia, Y.; Zichichi, A.; Bargende, A.; Crittenden, J.; Desch, K.; Diekmann, B.; Doeker, T.; Eckert, M.; Feld, L.; Frey, A.; Geerts, M.; Geitz, G.; Grothe, M.; Haas, T.; Hartmann, H.; Haun, D.; Heinloth, K.; Hilger, E.; Jakob, H.-P.; Katz, U. F.; Mari, S. M.; Mass, A.; Mengel, S.; Mollen, J.; Paul, E.; Rembser, Ch.; Schattevoy, R.; Schramm, D.; Stamm, J.; Wedemeyer, R.; Campbell-Robson, S.; Cassidy, A.; Dyce, N.; Foster, B.; George, S.; Gilmore, R.; Heath, G. P.; Heath, H. F.; Llewellyn, T. J.; Morgado, C. J.; Norman, D. J.; O'Mara, J. A.; Tapper, R. J.; Wilson, S. S.; Yoshida, R.; Rau, R. R.; Arneodo, M.; Iannotti, L.; Schioppa, M.; Susinno, G.; Bernstein, A.; Caldwell, A.; Cartiglia, N.; Parsons, J. A.; Ritz, S.; Sciulli, F.; Straub, P. B.; Wai, L.; Yang, S.; Zhu, Q.; Borzemski, P.; Chwastowski, J.; Eskreys, A.; Piotrzkowski, K.; Zachara, M.; Zawiejski, L.; Adamczyk, L.; Bednarek, B.; Jeleń, K.; Kisielewska, D.; Kowalski, T.; Rulikowska-Zarȩbska, E.; Suszycki, L.; ZajaÇ, J.; Kotański, A.; Przybycień, M.; Bauerdick, L. A.; Behrens, U.; Beier, H.; Bienlein, J. K.; Coldewey, C.; Deppe, O.; Desler, K.; Drews, G.; Flasiński, M.; Gilkinson, D. J.; Glasman, C.; Göttlicher, P.; Grosse-Knetter, J.; Gutjahr, B.; Hain, W.; Hasell, D.; Hessling, H.; Hultschig, H.; Iga, Y.; Joos, P.; Kasemann, M.; Klanner, R.; Koch, W.; Köpke, L.; Kötz, U.; Kowalski, H.; Labs, J.; Ladage, A.; Löhr, B.; Löwe, M.; Lüke, D.; Mańczak, O.; Ng, J. S.; Nickel, S.; Notz, D.; Ohrenberg, K.; Roco, M.; Rohde, M.; Roldán, J.; Schneekloth, U.; Schulz, W.; Selonke, F.; Stiliaris, E.; Surrow, B.; Voss, T.; Westphal, D.; Wolf, G.; Youngman, C.; Zhou, J. F.; Grabosch, H. J.; Kharchilava, A.; Leich, A.; Mattingly, M.; Meyer, A.; Schlenstedt, S.; Wulff, N.; Barbagli, G.; Pelfer, P.; Anzivino, G.; Maccarrone, G.; de Pasquale, S.; Votano, L.; Bamberger, A.; Eisenhardt, S.; Freidhof, A.; Söldner-Rembold, S.; Schroeder, J.; Trefzger, T.; Brook, N. H.; Bussey, P. J.; Doyle, A. T.; Fleck, J. I.; Saxon, D. H.; Utley, M. L.; Wilson, A. S.; Dannemann, A.; Holm, U.; Horstmann, D.; Neumann, T.; Sinkus, R.; Wick, K.; Badura, E.; Burow, B. D.; Hagge, L.; Lohrmann, E.; Mainusch, J.; Milewski, J.; Nakahata, M.; Pavel, N.; Poelz, G.; Schott, W.; Zetsche, F.; Bacon, T. C.; Butterworth, I.; Gallo, E.; Harris, V. L.; Hung, B. Y.; Long, K. R.; Miller, D. B.; Morawitz, P. P.; Prinias, A.; Sedgbeer, J. K.; Whitfield, A. F.; Mallik, U.; McCliment, E.; Wang, M. Z.; Wang, S. M.; Wu, J. T.; Zhang, Y.; Cloth, P.; Filges, D.; An, S. H.; Hong, S. M.; Nam, S. W.; Park, S. K.; Suh, M. H.; Yon, S. H.; Imlay, R.; Kartik, S.; Kim, H.-J.; McNeil, R. R.; Metcalf, W.; Nadendla, V. K.; Barreiro, F.; Cases, G.; Graciani, R.; Hernández, J. M.; Hervás, L.; Labarga, L.; del Peso, J.; Puga, J.; Terron, J.; de Trocóniz, J. F.; Smith, G. R.; Corriveau, F.; Hanna, D. S.; Hartmann, J.; Hung, L. W.; Lim, J. N.; Matthews, C. G.; Patel, P. M.; Sinclair, L. E.; Stairs, D. G.; St. Laurent, M.; Ullmann, R.; Zacek, G.; Bashkirov, V.; Dolgoshein, B. A.; Stifutkin, A.; Bashindzhagyan, G. L.; Ermolov, P. F.; Gladilin, L. K.; Golubkov, Y. A.; Kobrin, V. D.; Kuzmin, V. A.; Proskuryakov, A. S.; Savin, A. A.; Shcheglova, L. M.; Solomin, A. N.; Zotov, N. P.; Botje, M.; Chlebana, F.; Dake, A.; Engelen, J.; de Kamps, M.; Kooijman, P.; Kruse, A.; Tiecke, H.; Verkerke, W.; Vreeswijk, M.; Wiggers, L.; de Wolf, E.; van Woudenberg, R.; Acosta, D.; Bylsma, B.; Durkin, L. S.; Honscheid, K.; Li, C.; Ling, T. Y.; McLean, K. W.; Murray, W. N.; Park, I. H.; Romanowski, T. A.; Seidlein, R.; Bailey, D. S.; Blair, G. A.; Byrne, A.; Cashmore, R. J.; Cooper-Sarkar, A. M.; Daniels, D.; Devenish, R. C.; Harnew, N.; Lancaster, M.; Luffman, P. E.; Lindemann, L.; McFall, J. D.; Nath, C.; Noyes, V. A.; Quadt, A.; Uijterwaal, H.; Walczak, R.; Wilson, F. F.; Yip, T.; Abbiendi, G.; Bertolin, A.; Brugnera, R.; Carlin, R.; dal Corso, F.; de Giorgi, M.; Dosselli, U.; Limentani, S.; Morandin, M.; Posocco, M.; Stanco, L.; Stroili, R.; Voci, C.; Bulmahn, J.; Butterworth, J. M.; Feild, R. G.; Oh, B. Y.; Whitmore, J. J.; D'Agostini, G.; Marini, G.; Nigro, A.; Tassi, E.; Hart, J. C.; McCubbin, N. A.; Prytz, K.; Shah, T. P.; Short, T. L.; Barberis, E.; Dubbs, T.; Heusch, C.; van Hook, M.; Hubbard, B.; Lockman, W.; Rahn, J. T.; Sadrozinski, H. F.-W.; Seiden, A.; Biltzinger, J.; Schwarzer, O.; Seifert, R. J.; Walenta, A. H.; Zech, G.; Abramowicz, H.; Briskin, G.; Dagan, S.; Levy, A.; Hasegawa, T.; Hazumi, M.; Ishii, T.; Kuze, M.; Mine, S.; Nagasawa, Y.; Nakao, M.; Suzuki, I.; Tokushuku, K.; Yamada, S.; Yamazaki, Y.; Chiba, M.; Hamatsu, R.; Hirose, T.; Homma, K.; Kitamura, S.; Nakamitsu, Y.; Yamauchi, K.; Cirio, R.; Costa, M.; Ferrero, M. I.; Lamberti, L.; Maselli, S.; Peroni, C.; Sacchi, R.; Solano, A.; Staiano, A.; Dardo, M.; Bailey, D. C.; Bandyopadhyay, D.; Benard, F.; Brkic, M.; Crombie, M. B.; Gingrich, D. M.; Hartner, G. F.; Joo, K. K.; Levman, G. M.; Martin, J. F.; Orr, R. S.; Sampson, C. R.; Teuscher, R. J.; Catterall, C. D.; Jones, T. W.; Kaziewicz, P. B.; Lane, J. B.; Saunders, R. L.; Shulman, J.; Blankenship, K.; Kochocki, J.; Lu, B.; Mo, L. W.; Bogusz, W.; Charchuła, K.; Ciborowski, J.; Gajewski, J.; Grzelak, G.; Kasprzak, M.; Krzyżanowski, M.; Muchorowski, K.; Nowak, R. J.; Pawlak, J. M.; Tymieniecka, T.; Wróblewski, A. K.; Zakrzewski, J. A.; Żarnecki, A. F.; Adamus, M.; Eisenberg, Y.; Karshon, U.; Revel, D.; Zer-Zion, D.; Ali, I.; Badgett, W. F.; Behrens, B.; Dasu, S.; Fordham, C.; Foudas, C.; Goussiou, A.; Loveless, R. J.; Reeder, D. D.; Silverstein, S.; Smith, W. H.; Vaiciulis, A.; Wodarczyk, M.; Tsurugai, T.; Bhadra, S.; Cardy, M. L.; Fagerstroem, C.-P.; Frisken, W. R.; Furutani, K. M.; Khakzad, M.; Schmidke, W. B.

1995-08-01

Deep inelastic e-p scattering has been studied in both the charged current (CC) and neutral current (NC) reactions at momentum transfers squared Q2 above 400 GeV2 using the ZEUS detector at the HERA ep collider. The CC and NC total cross sections, the NC to CC cross section ratio, and the differential cross sections dσ/dQ2 are presented. From the Q2 dependence of the CC cross section, the mass term in the CC propagator is determined to be MW = 76+/-16+/-13 GeV.

Improvement of automatic control system for high-speed current collectors

NASA Astrophysics Data System (ADS)

Sidorov, O. A.; Goryunov, V. N.; Golubkov, A. S.

2018-01-01

The article considers the ways of regulation of pantographs to provide quality and reliability of current collection at high speeds. To assess impact of regulation was proposed integral criterion of the quality of current collection, taking into account efficiency and reliability of operation of the pantograph. The study was carried out using mathematical model of interaction of pantograph and catenary system, allowing to assess contact force and intensity of arcing at the contact zone at different movement speeds. The simulation results allowed us to estimate the efficiency of different methods of regulation of pantographs and determine the best option.

Investigating the microstructural and neurochemical environment within the basal ganglia of current methamphetamine abusers.

PubMed

Lin, Joanne C; Jan, Reem K; Kydd, Rob R; Russell, Bruce R

2015-04-01

Methamphetamine is a highly addictive psychostimulant and the medical, social, and economic consequences associated with its use have become a major international problem. Current evidence has shown methamphetamine to be particularly neurotoxic to dopamine neurons and striatal structures within the basal ganglia. A previous study from our laboratory demonstrated larger putamen volumes in actively using methamphetamine-dependent participants. The purpose of this current study was to determine whether striatal structures in the same sample of participants also exhibit pathology on the microstructural and molecular level. Diffusion tensor imaging (DTI) and magnetic resonance spectroscopy (MRS) were carried out in current methamphetamine users (n = 18) and healthy controls (n = 22) to investigate diffusion indices and neurometabolite levels in the basal ganglia. Contrary to findings from previous DTI and MRS studies, no significant differences in diffusion indices or metabolite levels were observed in the basal ganglia regions of current methamphetamine users. These findings differ from those reported in abstinent users and the absence of diffusion and neurochemical abnormalities may suggest that striatal enlargement in current methamphetamine use may be due to mechanisms other than edema and glial proliferation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Transcranial Direct Current Stimulation of the Temporoparietal Junction and Inferior Frontal Cortex Improves Imitation-Inhibition and Perspective-Taking with no Effect on the Autism-Spectrum Quotient Score.

PubMed

Nobusako, Satoshi; Nishi, Yuki; Nishi, Yuki; Shuto, Takashi; Asano, Daiki; Osumi, Michihiro; Morioka, Shu

2017-01-01

Lesions to brain regions such as the temporoparietal junction (TPJ) and inferior frontal cortex (IFC) are thought to cause autism-spectrum disorder (ASD). Previous studies indicated that transcranial direct current stimulation (tDCS) of the right TPJ improves social cognitive functions such as imitation-inhibition and perspective-taking. Although previous work shows that tDCS of the right IFC improves imitation-inhibition, its effects on perspective-taking have yet to be determined. In addition, the role of the TPJ and IFC in determining the Autism-Spectrum Quotient (AQ), which is a measure of autism spectrum traits, is still unclear. Thus, the current study performed tDCS on the right TPJ and the right IFC of healthy adults, and examined its effects on imitation-inhibition, perspective-taking and AQ scores. Based on previous studies, we hypothesized that anodal tDCS of the right IFC and right TPJ would improve imitation-inhibition, perspective-taking and the AQ score. Anodal tDCS of the right TPJ or IFC significantly decreased the interference effect in an imitation-inhibition task and the cost of perspective-taking in a perspective-taking task, in comparison to the sham stimulation control. These findings indicated that both the TPJ and the IFC play a role in imitation-inhibition and perspective-taking, i.e., control of self and other representations. However, anodal stimulation of the right TPJ and the right IFC did not alter participants' AQ. This finding conflicts with results from previous brain imaging studies, which could be attributed to methodological differences such as variation in sex, age and ASD. Therefore, further research is necessary to determine the relationship between the TPJ and IFC, and the AQ.

Transcranial Direct Current Stimulation of the Temporoparietal Junction and Inferior Frontal Cortex Improves Imitation-Inhibition and Perspective-Taking with no Effect on the Autism-Spectrum Quotient Score

PubMed Central

Nobusako, Satoshi; Nishi, Yuki; Nishi, Yuki; Shuto, Takashi; Asano, Daiki; Osumi, Michihiro; Morioka, Shu

2017-01-01

Lesions to brain regions such as the temporoparietal junction (TPJ) and inferior frontal cortex (IFC) are thought to cause autism-spectrum disorder (ASD). Previous studies indicated that transcranial direct current stimulation (tDCS) of the right TPJ improves social cognitive functions such as imitation-inhibition and perspective-taking. Although previous work shows that tDCS of the right IFC improves imitation-inhibition, its effects on perspective-taking have yet to be determined. In addition, the role of the TPJ and IFC in determining the Autism-Spectrum Quotient (AQ), which is a measure of autism spectrum traits, is still unclear. Thus, the current study performed tDCS on the right TPJ and the right IFC of healthy adults, and examined its effects on imitation-inhibition, perspective-taking and AQ scores. Based on previous studies, we hypothesized that anodal tDCS of the right IFC and right TPJ would improve imitation-inhibition, perspective-taking and the AQ score. Anodal tDCS of the right TPJ or IFC significantly decreased the interference effect in an imitation-inhibition task and the cost of perspective-taking in a perspective-taking task, in comparison to the sham stimulation control. These findings indicated that both the TPJ and the IFC play a role in imitation-inhibition and perspective-taking, i.e., control of self and other representations. However, anodal stimulation of the right TPJ and the right IFC did not alter participants’ AQ. This finding conflicts with results from previous brain imaging studies, which could be attributed to methodological differences such as variation in sex, age and ASD. Therefore, further research is necessary to determine the relationship between the TPJ and IFC, and the AQ. PMID:28536512

Determining the Economic Feasibility of Using Produced Water for Agriculture in Colorado Through Life Cycle Cost Analyses

NASA Astrophysics Data System (ADS)

Dolan, F.; Blaine, A. C.; Hogue, T. S.

2016-12-01

To combat the need for new sources of water in Colorado, the current research looks to produced water as a potential source. Produced water, the water produced alongside oil and gas in a well, is currently viewed as a high-volume waste product; however, this water can potentially be used to irrigate food or non-food crops after treatment. Kern County in California has been using produced water for this purpose for over 20 years and a town in Colorado has followed suit. Our research seeks to determine how Wellington, CO overcame economic, legal, social, and technological barriers in order to put produced water to beneficial use. Life cycle cost analyses of produced water in three counties in Colorado are conducted to determine the economic feasibility of using produced water for irrigation on a broad scale. The current study is chosen based on the quality and quantity of the region's produced water as well as the need for new sources of water within the county. The results of this research will help in the transition between viewing produced water as a waste product and using it as a tool to help secure Colorado's water future.

Association Between Smoking and Size of Anal Warts in HIV-infected Women

PubMed Central

Luu, HN; Amirian, ES; Beasley, RP; Piller, L; Chan, W; Scheurer, ME

2015-01-01

While the association between smoking and HPV infection, cervical cancer, and anal cancer has been well studied, evidence on the association between cigarette smoking and anal warts is limited. The purpose of this study was to investigate if cigarette smoking status influences the size of anal warts over time in HIV-infected women in a sample of 976 HIV-infected women from the Women’s Interagency HIV Study (WIHS). A linear mixed model was used to determine the effect of smoking on anal wart size. Even though women who were currently smokers had larger anal warts at baseline and slower growth rate of anal wart size after each visit than women who were not current smokers, there was no association between size of anal wart and current smoking status over time. Further studies on the role of smoking and interaction between smoking and other risk factors, however, should be explored. PMID:23155099

Determining resistivity of a formation adjacent to a borehole having casing with an apparatus having all current conducting electrodes within the cased well

DOEpatents

Vail, III, William Banning

2001-01-01

Methods of operation of different types of multiple electrode apparatus vertically disposed in a cased well to measure information useful to determine the resistivity of adjacent geological formations from within the cased well are described. The multiple electrode apparatus has a plurality of spaced apart voltage measurement electrodes that electrically engage a portion of the interior of the cased well. During measurements of information useful to determine formation resistivity, current is conducted between a first current conducting electrode in electrical contact with the interior of the cased well to a second current conducting electrode that is also in electrical contact with the interior of the cased well. The first and second current conducting electrodes are separated by a distance sufficient so that at least a portion of the current conducted between the first and second current conducting electrodes is conducted through the geological formation of interest.

Childhood Medical and Behavioral Consequences of Maternal Cocaine Use1

PubMed Central

Singer, Lynn; Farkas, Kathleen; Kliegman, Robert

2014-01-01

Reviewed available studies of the impact of fetal cocaine exposure on child medical and developmental outcome, as well as the current status of clinical psychological interventions and research strategies. Current studies are inconclusive but suggest that prenatal exposure to crack-cocaine can have significant effects on the growth and neurological development of the infant, with the potential of later learning and behavioral disabilities. Social-environmental correlates of maternal cocaine use are confounding factors with known negative effects on child outcome. Large, population-based studies using multivariate analyses are needed to determine the independent effects of cocaine on child outcome relative to other confounding variables. PMID:1382125

Current Situation, Determinants, and Solutions to Drug Shortages in Shaanxi Province, China: A Qualitative Study.

PubMed

Yang, Caijun; Wu, Lina; Cai, Wenfang; Zhu, Wenwen; Shen, Qian; Li, Zongjie; Fang, Yu

2016-01-01

Drug shortages were a complex global problem. The aim of this study was to analyze, characterize, and assess the drug shortages, and identify possible solutions in Shaanxi Province, western China. A qualitative methodological approach was conducted during May-June 2015 and December 2015-January 2016. Semi-structured interviews were performed to gather information from representatives of hospital pharmacists, wholesalers, pharmaceutical producers, and local health authorities. Thirty participants took part in the study. Eight traditional Chinese medicines and 87 types of biologicals and chemicals were reported to be in short supply. Most were essential medicines. Five main determinants of drug shortages were detected: too low prices, too low market demands, Good Manufacturing Practice (GMP) issues, materials issues, and approval issues for imported drugs. Five different solutions were proposed by the participants: 1) let the market decide the drug price; 2) establish an information platform; 3) establish a reserve system; 4) enhance the communication among the three parties in the supply chain; and 5) improve hospital inventory management. Western China was currently experiencing a serious drug shortage. Numerous reasons for the shortage were identified. Most drug shortages in China were currently because of "too low prices." To solve this problem, all of the stakeholders, especially the government, needed to participate in managing the drug shortages.

A Circular Microstrip Antenna Sensor for Direction Sensitive Strain Evaluation †

PubMed Central

Herbko, Michal

2018-01-01

In this paper, a circular microstrip antenna for stress evaluation is studied. This kind of microstrip sensor can be utilized in structural health monitoring systems. Reflection coefficient S11 is measured to determine deformation/strain value. The proposed sensor is adhesively connected to the studied sample. Applied strain causes a change in patch geometry and influences current distribution both in patch and ground plane. Changing the current flow in patch influences the value of resonant frequency. In this paper, two different resonant frequencies were analysed because in each case, different current distributions in patch were obtained. The sensor was designed for operating frequency of 2.5 GHz (at fundamental mode), which results in a diameter less than 55 mm. Obtained sensitivity was up to 1 MHz/100 MPa, resolution depends on utilized vector network analyser. Moreover, the directional characteristics for both resonant frequencies were defined, studied using numerical model and verified by measurements. Thus far, microstrip antennas have been used in deformation measurement only if the direction of external force was well known. Obtained directional characteristics of the sensor allow the determination of direction and value of stress by one sensor. This method of measurement can be an alternative to the rosette strain gauge. PMID:29361697

Impact Damage and Erosion of Ceramics and Composites.

DTIC Science & Technology

1980-12-31

local fracture toughness, Keff’ with crack length, a, was used to determine the fracture criticality. Specifically, the fracture toughness was chosen...A complete description of strength behaviors thus requires an experimental determination of the local toughness, One of us (A. V. Virkar) is currently...34Simulated Strength - Grain Size Study Using Glass- Glass Ceramic Composite System," submitted to Journal of Materials Science, (1979). -~_ 6 I ~ -_- 0

Riparian Ecosystem Management at Military Installations: Determination of Impacts and Evaluation of Restoration and Enhancement Strategies

DTIC Science & Technology

2007-06-01

forests , and the water filtration function performed by these ecosystems may be at risk . Maloney, K. O. and J. W. Feminella. 2006. Evaluation of...additions to perennial streams. Phase 1 – Effects of Disturbance In our studies of sedimentation effects on riparian forests , vegetation...riparian forests associated with ephemeral streams. We determined thresholds beyond which both long-term and current rates of sedimentation

Method of operating a thermoelectric generator

DOEpatents

Reynolds, Michael G; Cowgill, Joshua D

2013-11-05

A method for operating a thermoelectric generator supplying a variable-load component includes commanding the variable-load component to operate at a first output and determining a first load current and a first load voltage to the variable-load component while operating at the commanded first output. The method also includes commanding the variable-load component to operate at a second output and determining a second load current and a second load voltage to the variable-load component while operating at the commanded second output. The method includes calculating a maximum power output of the thermoelectric generator from the determined first load current and voltage and the determined second load current and voltage, and commanding the variable-load component to operate at a third output. The commanded third output is configured to draw the calculated maximum power output from the thermoelectric generator.

Determining heavy metals in spent compact fluorescent lamps (CFLs) and their waste management challenges: some strategies for improving current conditions.

PubMed

Taghipour, Hassan; Amjad, Zahra; Jafarabadi, Mohamad Asghari; Gholampour, Akbar; Norouz, Prviz

2014-07-01

From environmental viewpoint, the most important advantage of compact fluorescent lamps (CFLs) is reduction of green house gas emissions. But their significant disadvantage is disposal of spent lamps because of containing a few milligrams of toxic metals, especially mercury and lead. For a successful implementation of any waste management plan, availability of sufficient and accurate information on quantities and compositions of the generated waste and current management conditions is a fundamental prerequisite. In this study, CFLs were selected among 20 different brands in Iran. Content of heavy metals including mercury, lead, nickel, arsenic and chromium was determined by inductive coupled plasma (ICP). Two cities, Tehran and Tabriz, were selected for assessing the current waste management condition of CFLs. The study found that waste generation amount of CFLs in the country was about 159.80, 183.82 and 153.75 million per year in 2010, 2011 and 2012, respectively. Waste generation rate of CFLs in Iran was determined to be 2.05 per person in 2012. The average amount of mercury, lead, nickel, arsenic and chromium was 0.417, 2.33, 0.064, 0.056 and 0.012 mg per lamp, respectively. Currently, waste of CFLs is disposed by municipal waste stream in waste landfills. For improving the current conditions, we propose by considering the successful experience of extended producer responsibility (EPR) in other electronic waste management. The EPR program with advanced recycling fee (ARF) is implemented for collecting and then recycling CFLs. For encouraging consumers to take the spent CFLs back at the end of the products' useful life, a proportion of ARF (for example, 50%) can be refunded. On the other hand, the government and Environmental Protection Agency should support and encourage recycling companies of CFLs both technically and financially in the first place. Copyright © 2014 Elsevier Ltd. All rights reserved.

Mothers' Preferences and Willingness to Pay for Human Papillomavirus Vaccination for Their Daughters: A Discrete Choice Experiment in Hong Kong.

PubMed

Wong, Carlos K H; Man, Kenneth K C; Ip, Patrick; Kwan, Mike; McGhee, Sarah M

2018-05-01

To determine the preference of mothers in Hong Kong and their willingness to pay (WTP) for human papillomavirus (HPV) vaccination for their daughters. A discrete choice experiment survey with a two-alternative study design was developed. Data were collected from pediatric specialist outpatient clinics from 482 mothers with daughters aged between 8 and 17 years. Preferences of the four attributes of HPV vaccines (protection against cervical cancer, protection duration, side effects, and out-of-pocket costs) were evaluated. The marginal and overall WTP were estimated using multinomial logistic regression. A subgroup analysis was conducted to explore the impact of socioeconomic factors on mothers' WTP. Side effects, protection against cervical cancer, protection duration, and out-of-pocket cost determined the decision to receive or not receive the vaccine. All attributes had a statistically significant effect on the preference of and the WTP for the vaccine. Maximum WTP for ideal vaccines (i.e., 100% protection, lifetime protection duration, and 0% side effects) was HK$8976 (US $1129). The estimated WTP for vaccines currently available was HK$1620 (US $208), lower than the current market price. Among those who had a monthly household income of more than HK$100,000 (US $12,821), the WTP for vaccines currently offered was higher than the market price. This study provides new data on how features of the HPV vaccine are viewed and valued by mothers by determining their perception of ideal or improved and current vaccine technologies. These findings could contribute to future policies on the improvement of HPV vaccine and be useful for the immunization service in Hong Kong. Copyright © 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

Comparison of Steroid Modulation of Spontaneous Inhibitory Postsynaptic Currents in Cultured Hippocampal Neurons and Steady-State Single-Channel Currents from Heterologously Expressed α1β2γ2L GABAA Receptors

PubMed Central

Chakrabarti, Sampurna; Qian, Mingxing; Krishnan, Kathiresan; Covey, Douglas F.; Mennerick, Steven

2016-01-01

Neuroactive steroids are efficacious modulators of γ-aminobutyric acid type A receptor (GABAA) receptor function. The effects of steroids on the GABAA receptor are typically determined by comparing steady-state single-channel open probability or macroscopic peak responses elicited by GABA in the absence and presence of a steroid. Due to differences in activation conditions (exposure duration, concentration of agonist), it is not obvious whether modulation measured using typical experimental protocols can be used to accurately predict the effect of a modulator on native receptors under physiologic conditions. In the present study, we examined the effects of 14 neuroactive steroids and analogs on the properties of spontaneous inhibitory postsynaptic currents (sIPSCs) in cultured rat hippocampal neurons. The goal was to determine whether the magnitude of modulation of the decay time course of sIPSCs correlates with the extent of modulation and kinetic properties of potentiation as determined in previous single-channel studies. The steroids were selected to cover a wide range of efficacy on heterologously expressed rat α1β2γ2L GABAA receptors, ranging from essentially inert to highly efficacious (strong potentiators of single-channel and macroscopic peak responses). The data indicate a strong correlation between prolongation of the decay time course of sIPSCs and potentiation of single-channel open probability. Furthermore, changes in intracluster closed time distributions were the single best predictor of prolongation of sIPSCs. We infer that the information obtained in steady-state single-channel recordings can be used to forecast modulation of synaptic currents. PMID:26769414

Spin dependent transport and spin transfer in nanoconstrictions and current confined nanomagnets

NASA Astrophysics Data System (ADS)

Ozatay, Ozhan

In this thesis, I have employed point contact spectroscopy to determine the nature of electron transport across constrained domain walls in a ferromagnetic nanocontact and to uncover the relationship between ballisticity of electron transport and domain wall magnetoresistance. In the range of hole sizes studied (from 10 to 3 nm) the resulting magnetoresistance was found to be less than 0.5% and one that increases with decreasing contact size. I have used point contacts as local probes, to study the spin dependent transport across Ferromagnet/Normal Metal/Ferromagnet(FM/NM/FM) trilayers as well as the consequences of localized spin polarized current injection into a nano magnet on spin angular momentum transfer and high frequency magnetization dynamics. I have demonstrated that absolute values for spin transfer switching critical currents are reduced in this new geometry as compared to uniform current injection. I have also performed micromagnetic simulations to determine the evolution of magnetization under the application of magnetic fields and currents to gain more insights into experimental results. I have used Scanning Transmission Electron Microscopy (STEM), X-Ray Photoemission Spectroscopy (XPS) and Electron Energy Loss Spectroscopy (EELS) techniques to characterize the interfacial mixing and oxygen diffusion in the metallic multilayers of interest. I have shown that the Ta/CuOx bilayer structure provides a smooth substrate by improving interfacial roughness due to grain boundary diffusion of oxygen and reaction with Ta that fills in the grain boundary gaps in Cu. Analysis of the Py/AlOx interface proved a strong oxidation passivation on the Py surface by Al coating accompanied by Fe segregation into the alumina. I have utilized the characterization results to design a new nanomagnet whose sidewalls are protected from adventitious sidewall oxide layers and yields improved device performance. The oxide layers that naturally develop at the sidewalls of Py nanomagnets cause an enhancement in magnetic damping especially for temperatures below the blocking temperature of the AFM layer (≤40K). Studies with pillars protected by Al coating and ones with more NiO coating (˜2.5 nm) shed light onto the role of surface oxides in determining temperature dependent behaviour of both spin torque and field driven switching characteristics.

The effect of secondhand smoke exposure on the association between active cigarette smoking and colorectal cancer

PubMed Central

Peppone, Luke J.; Reid, Mary E.; Moysich, Kirsten B.; Morrow, Gary R.; Jean-Pierre, Pascal; Mohile, Supriya G.; Darling, Tom V.; Hyland, Andrew

2011-01-01

Background Studies published prior to 1980 failed to find an association between smoking and colorectal cancer, while subsequent studies reported an association after accounting for a three to four decade initiation period. The aims of this study were to determine the effect of accounting for secondhand smoke (SHS) exposure on the association between smoking and colorectal cancer and to determine the association between SHS and colorectal cancer. Methods Approximately 1,200 colorectal cancer cases treated at Roswell Park Cancer Institute between 1982 and 1998 were matched to 2,400 malignancy-free controls. The effect of accounting for SHS exposure was determined by comparing the odds ratios (OR) for each smoking variable in the overall sample and then for those who reported no current SHS exposure. Results A small, significant increase in colorectal cancer odds was noted for heavy, long-term smoking males when not accounting for SHS exposure (>45 PY: OR = 1.34; 95% CI 1.04–1.72). OR increased when the analyses were restricted to individuals reporting no current SHS exposure (>45 PY: OR = 2.40; 95% CI 1.36–4.23). Conclusions Accounting for SHS exposure resulted in a substantial increase in the odds of colorectal cancer for all smoking variables in this study. Future studies should account for SHS exposure when examining the association between smoking and colorectal cancer. PMID:20376547

Scientific Inquiry Competency Perception Scale (The Case of Kazak Post-Graduate Students) Reliability and Validity Study

ERIC Educational Resources Information Center

Gelisli, Yücel; Beisenbayeva, Lyazzat

2017-01-01

The purpose of the current study is to develop a reliable scale to be used to determine the scientific inquiry competency perception of post-graduate students engaged in post-graduate studies in the field of educational sciences and teacher education in Kazakhstan. The study employed the descriptive method. Within the context of the study, a scale…

Computational analysis of thresholds for magnetophosphenes

NASA Astrophysics Data System (ADS)

Laakso, Ilkka; Hirata, Akimasa

2012-10-01

In international guidelines, basic restriction limits on the exposure of humans to low-frequency magnetic and electric fields are set with the objective of preventing the generation of phosphenes, visual sensations of flashing light not caused by light. Measured data on magnetophosphenes, i.e. phosphenes caused by a magnetically induced electric field on the retina, are available from volunteer studies. However, there is no simple way for determining the retinal threshold electric field or current density from the measured threshold magnetic flux density. In this study, the experimental field configuration of a previous study, in which phosphenes were generated in volunteers by exposing their heads to a magnetic field between the poles of an electromagnet, is computationally reproduced. The finite-element method is used for determining the induced electric field and current in five different MRI-based anatomical models of the head. The direction of the induced current density on the retina is dominantly radial to the eyeball, and the maximum induced current density is observed at the superior and inferior sides of the retina, which agrees with literature data on the location of magnetophosphenes at the periphery of the visual field. On the basis of computed data, the macroscopic retinal threshold current density for phosphenes at 20 Hz can be estimated as 10 mA m-2 (-20% to  + 30%, depending on the anatomical model); this current density corresponds to an induced eddy current of 14 μA (-20% to  + 10%), and about 20% of this eddy current flows through each eye. The ICNIRP basic restriction limit for the induced electric field in the case of occupational exposure is not exceeded until the magnetic flux density is about two to three times the measured threshold for magnetophosphenes, so the basic restriction limit does not seem to be conservative. However, the reasons for the non-conservativeness are purely technical: removal of the highest 1% of electric field values by taking the 99th percentile as recommended by the ICNIRP leads to the underestimation of the induced electric field, and there are difficulties in applying the basic restriction limit for the retinal electric field.

Pharmacogenetics of asthma: toward precision medicine.

PubMed

Kersten, Elin T G; Koppelman, Gerard H

2017-01-01

Although currently available drugs to treat asthma are effective in most patients, a proportion of patients do not respond or experience side-effects; which is partly genetically determined. Pharmacogenetics is the study of how genetic variations influence drug response. In this review, we summarize prior results and recent studies in pharmacogenetics to determine if we can use genetic profiles for personalized treatment of asthma. The field of pharmacogenetics has moved from candidate gene studies in single populations toward genome-wide association studies and meta-analysis of multiple studies. New technologies have been used to enrich results, and an expanding number of genetic loci have been associated with therapeutic responses to asthma drugs. Prospective, genotype-stratified treatment studies have been conducted for β2-agonists, showing attenuated response in children carrying the Arg16 variant in the β2-adrenoreceptor gene. Although there has been much progress, many findings have not been replicated and currently known genetic loci only account for a fraction of variability in drug response. More research is necessary to translate into clinical practice. A polygenic predictive approach integrated in complex networks with other 'omics' technologies could aid to achieve this goal. Finally, to change clinical practice, studies that compare precision medicine with traditional medicine are needed.

Benefits Derived From Laser Ranging Measurements for Orbit Determination of the GPS Satellite Orbit

NASA Technical Reports Server (NTRS)

Welch, Bryan W.

2007-01-01

While navigation systems for the determination of the orbit of the Global Position System (GPS) have proven to be very effective, the current research is examining methods to lower the error in the GPS satellite ephemerides below their current level. Two GPS satellites that are currently in orbit carry retro-reflectors onboard. One notion to reduce the error in the satellite ephemerides is to utilize the retro-reflectors via laser ranging measurements taken from multiple Earth ground stations. Analysis has been performed to determine the level of reduction in the semi-major axis covariance of the GPS satellites, when laser ranging measurements are supplemented to the radiometric station keeping, which the satellites undergo. Six ground tracking systems are studied to estimate the performance of the satellite. The first system is the baseline current system approach which provides pseudo-range and integrated Doppler measurements from six ground stations. The remaining five ground tracking systems utilize all measurements from the current system and laser ranging measurements from the additional ground stations utilized within those systems. Station locations for the additional ground sites were taken from a listing of laser ranging ground stations from the International Laser Ranging Service. Results show reductions in state covariance estimates when utilizing laser ranging measurements to solve for the satellite s position component of the state vector. Results also show dependency on the number of ground stations providing laser ranging measurements, orientation of the satellite to the ground stations, and the initial covariance of the satellite's state vector.

Determination of the optimal cutoff value for a serological assay: an example using the Johne's Absorbed EIA.

PubMed Central

Ridge, S E; Vizard, A L

1993-01-01

Traditionally, in order to improve diagnostic accuracy, existing tests have been replaced with newly developed diagnostic tests with superior sensitivity and specificity. However, it is possible to improve existing tests by altering the cutoff value chosen to distinguish infected individuals from uninfected individuals. This paper uses data obtained from an investigation of the operating characteristics of the Johne's Absorbed EIA to demonstrate a method of determining a preferred cutoff value from several potentially useful cutoff settings. A method of determining the financial gain from using the preferred rather than the current cutoff value and a decision analysis method to assist in determining the optimal cutoff value when critical population parameters are not known with certainty are demonstrated. The results of this study indicate that the currently recommended cutoff value for the Johne's Absorbed EIA is only close to optimal when the disease prevalence is very low and false-positive test results are deemed to be very costly. In other situations, there were considerable financial advantages to using cutoff values calculated to maximize the benefit of testing. It is probable that the current cutoff values for other diagnostic tests may not be the most appropriate for every testing situation. This paper offers methods for identifying the cutoff value that maximizes the benefit of medical and veterinary diagnostic tests. PMID:8501227

Determination of plasma displacement based on eddy current diagnostics for the Keda Torus eXperiment

NASA Astrophysics Data System (ADS)

Tu, Cui; Li, Hong; Liu, Adi; Li, Zichao; Zhang, Yuan; You, Wei; Tan, Mingsheng; Luo, Bing; Adil, Yolbarsop; Hu, Jintong; Wu, Yanqi; Yan, Wentan; Xie, Jinlin; Lan, Tao; Mao, Wenzhe; Ding, Weixing; Xiao, Chijin; Zhuang, Ge; Liu, Wandong

2017-10-01

The measurement of plasma displacement is one of the most basic diagnostic tools in the study of plasma equilibrium and control in a toroidal magnetic confinement configuration. During pulse discharge, the eddy current induced in the vacuum vessel and shell will produce an additional magnetic field at the plasma boundary, which will have a significant impact on the measurement of plasma displacement using magnetic probes. In the newly built Keda Torus eXperiment (KTX) reversed field pinch device, the eddy current in the composite shell can be obtained at a high spatial resolution. This device offers a new way to determine the plasma displacement for KTX through the multipole moment expansion of the eddy current, which can be obtained by unique probe arrays installed on the inner and outer surfaces of the composite shell. In an ideal conductor shell approximation, the method of multipole moment expansion of the poloidal eddy current for measuring the plasma displacement in toroidal coordinates, is more accurate than the previous method based on symmetrical magnetic probes, which yielded results in cylindrical coordinates. Through an analytical analysis of many current filaments and numerical simulations of the current distribution in toroidal coordinates, the scaling relation between the first moment of the eddy current and the center of gravity of the plasma current is obtained. In addition, the origin of the multipole moment expansion of the eddy current in KTX is retrieved simultaneously. Preliminary data on the plasma displacement have been collected using these two methods during short pulse discharges in the KTX device, and the results of the two methods are in reasonable agreement.

Study of nonparticipation in an employee diabetes program.

PubMed

Brna, Stephanie A; Ruisinger, Janelle F; Howard, Patricia A; Barnes, Brian J; Hare, Sarah E

2012-01-01

To determine factors that affect nonparticipation in an employee diabetes program and factors that may increase participation in future employee health programs. Participants in this cross-sectional study were adults with type 1 or type 2 diabetes, 18 to 80 years of age, who were covered by employer insurance but chose not to participate in an employer-sponsored diabetes program. Potential factors affecting program participation were assessed through a face-to-face or mailed survey. Of 204 employees or their dependents eligible for the diabetes program, 75 (37%) chose not to participate. Among the nonparticipants, 46 (61%) were eligible for this study. A total of 22 surveys were collected for a 48% response rate. The majority of those individuals surveyed (91%) were aware of the diabetes program and had been notified by mail (42%) or phone (29%). Of those surveyed, 33% did not believe that program incentives had been sufficiently explained to them. Work schedule was not found to be a determinant of participation. More than one-half (52%) of responders identified satisfaction with their current diabetes management as the most notable reason for nonparticipation in the employee diabetes program. This study demonstrated that the primary reason for program nonparticipation was patient satisfaction with current physician management of their diabetes. In the future, companies offering health programs should emphasize that the program is being offered to supplement and complement current disease state management, not to replace it.

Ignition study of a petrol/CNG single cylinder engine

NASA Astrophysics Data System (ADS)

Khan, N.; Saleem, Z.; Mirza, A. A.

2005-11-01

Benefits of laser ignition over the electrical ignition system for Compressed Natural Gas (CNG) engines have fuelled automobile industry and led to an extensive research on basic characteristics to switch over to the emerging technologies. This study was undertaken to determine the electrical and physical characteristics of the electric spark ignition of single cylinder petrol/CNG engine to determine minimum ignition requirements and timeline of ignition events to use in subsequent laser ignition study. This communication briefly reviews the ongoing research activities and reports the results of this experimental study. The premixed petrol and CNG mixtures were tested for variation of current and voltage characteristics of the spark with speed of engine. The current magnitude of discharge circuit was found to vary linearly over a wide range of speed but the stroke to stroke fire time was found to vary nonlinearly. The DC voltage profiles were observed to fluctuate randomly during ignition process and staying constant in rest of the combustion cycle. Fire to fire peaks of current amplitudes fluctuated up to 10% of the peak values at constant speed but increased almost linearly with increase in speed. Technical barriers of laser ignition related to threshold minimum ignition energy, inter-pulse durations and firing sequence are discussed. Present findings provide a basic initiative and background information for designing suitable timeline algorithms for laser ignited leaner direct injected CNG engines.

Electric current locator

DOEpatents

King, Paul E [Corvallis, OR; Woodside, Charles Rigel [Corvallis, OR

2012-02-07

The disclosure herein provides an apparatus for location of a quantity of current vectors in an electrical device, where the current vector has a known direction and a known relative magnitude to an input current supplied to the electrical device. Mathematical constants used in Biot-Savart superposition equations are determined for the electrical device, the orientation of the apparatus, and relative magnitude of the current vector and the input current, and the apparatus utilizes magnetic field sensors oriented to a sensing plane to provide current vector location based on the solution of the Biot-Savart superposition equations. Description of required orientations between the apparatus and the electrical device are disclosed and various methods of determining the mathematical constants are presented.

Patterns of current and lifetime substance use in schizophrenia.

PubMed

Fowler, I L; Carr, V J; Carter, N T; Lewin, T J

1998-01-01

A structured interview and standardized rating scales were used to assess a sample of 194 outpatients with schizophrenia in a regional Australian mental health service for substance use, abuse, and dependence. Case manager assessments and urine drug screens were also used to determine substance use. Additional measurements included demographic information, history of criminal charges, symptom self-reports, personal hopefulness, and social support. The sample was predominantly male and showed relative instability in accommodations, and almost half had a history of criminal offenses, most frequently drug or alcohol related. The 6-month and lifetime prevalence of substance abuse or dependence was 26.8 and 59.8 percent, respectively, with alcohol, cannabis, and amphetamines being the most commonly abused substances. Current users of alcohol comprised 77.3 percent and current users of other nonprescribed substances (excluding tobacco and caffeine) comprised 29.9 percent of the sample. Rates of tobacco and caffeine consumption were high. There was a moderate degree of concordance between case manager determinations of a substance-use problem and research diagnoses. Subjects with current or lifetime diagnoses of substance abuse/dependence were predominantly young, single males with higher rates of criminal charges; however, there was no evidence of increased rates of suicide attempts, hospital admissions, or daily doses of antipsychotic drugs in these groups compared with subjects with no past or current diagnosis of substance abuse or dependence. Subjects with a current diagnosis of substance use were younger at first treatment and currently more symptomatic than those with no past or current substance use diagnosis. The picture emerging from this study replicates the high rate of substance abuse in persons with schizophrenia reported in North American studies but differs from the latter in finding a slightly different pattern of substances abused (i.e., absence of cocaine), reflecting relative differences in the availability of certain drugs.

Differential roles of two delayed rectifier potassium currents in regulation of ventricular action potential duration and arrhythmia susceptibility.

PubMed

Devenyi, Ryan A; Ortega, Francis A; Groenendaal, Willemijn; Krogh-Madsen, Trine; Christini, David J; Sobie, Eric A

2017-04-01

Arrhythmias result from disruptions to cardiac electrical activity, although the factors that control cellular action potentials are incompletely understood. We combined mathematical modelling with experiments in heart cells from guinea pigs to determine how cellular electrical activity is regulated. A mismatch between modelling predictions and the experimental results allowed us to construct an improved, more predictive mathematical model. The balance between two particular potassium currents dictates how heart cells respond to perturbations and their susceptibility to arrhythmias. Imbalances of ionic currents can destabilize the cardiac action potential and potentially trigger lethal cardiac arrhythmias. In the present study, we combined mathematical modelling with information-rich dynamic clamp experiments to determine the regulation of action potential morphology in guinea pig ventricular myocytes. Parameter sensitivity analysis was used to predict how changes in ionic currents alter action potential duration, and these were tested experimentally using dynamic clamp, a technique that allows for multiple perturbations to be tested in each cell. Surprisingly, we found that a leading mathematical model, developed with traditional approaches, systematically underestimated experimental responses to dynamic clamp perturbations. We then re-parameterized the model using a genetic algorithm, which allowed us to estimate ionic current levels in each of the cells studied. This unbiased model adjustment consistently predicted an increase in the rapid delayed rectifier K + current and a drastic decrease in the slow delayed rectifier K + current, and this prediction was validated experimentally. Subsequent simulations with the adjusted model generated the clinically relevant prediction that the slow delayed rectifier is better able to stabilize the action potential and suppress pro-arrhythmic events than the rapid delayed rectifier. In summary, iterative coupling of simulations and experiments enabled novel insight into how the balance between cardiac K + currents influences ventricular arrhythmia susceptibility. © 2016 The Authors. The Journal of Physiology © 2016 The Physiological Society.

Method for determining transport critical current densities and flux penetration depth in bulk superconductors

NASA Technical Reports Server (NTRS)

Israelsson, Ulf E. (Inventor); Strayer, Donald M. (Inventor)

1992-01-01

A contact-less method for determining transport critical current density and flux penetration depth in bulk superconductor material. A compressor having a hollow interior and a plunger for selectively reducing the free space area for distribution of the magnetic flux therein are formed of superconductor material. Analytical relationships, based upon the critical state model, Maxwell's equations and geometrical relationships define transport critical current density and flux penetration depth in terms of the initial trapped magnetic flux density and the ratio between initial and final magnetic flux densities whereby data may be reliably determined by means of the simple test apparatus for evaluating the current density and flux penetration depth.

Current density and catalyst-coated membrane resistance distribution of hydro-formed metallic bipolar plate fuel cell short stack with 250 cm2 active area

NASA Astrophysics Data System (ADS)

Haase, S.; Moser, M.; Hirschfeld, J. A.; Jozwiak, K.

2016-01-01

An automotive fuel cell with an active area of 250 cm2 is investigated in a 4-cell short stack with a current and temperature distribution device next to the bipolar plate with 560 current and 140 temperature segments. The electrical conductivities of the bipolar plate and gas diffusion layer assembly are determined ex-situ with this current scan shunt module. The applied fuel cell consists of bipolar plates constructed of 75-μm-thick, welded stainless-steel foils and a graphitic coating. The electrical conductivities of the bipolar plate and gas diffusion layer assembly are determined ex-situ with this module with a 6% deviation in in-plane conductivity. The current density distribution is evaluated up to 2.4 A cm-2. The entire cell's investigated volumetric power density is 4.7 kW l-1, and its gravimetric power density is 4.3 kW kg-1 at an average cell voltage of 0.5 V. The current density distribution is determined without influencing the operating cell. In addition, the current density distribution in the catalyst-coated membrane and its effective resistivity distribution with a finite volume discretisation of Ohm's law are evaluated. The deviation between the current density distributions in the catalyst-coated membrane and the bipolar plate is determined.

The Association between Sensation Seeking and E-cigarette Use in Texas Young Adults: A Cross-Sectional Study

PubMed Central

Case, Kathleen; Loukas, Alexandra; Harrell, Melissa; Wilkinson, Anna; Springer, Andrew; Pérez, Adriana; Creamer, MeLisa; Perry, Cheryl L.

2017-01-01

Objective To examine the associations between sensation seeking and ever and current e-cigarette use in Texas young adults (18–29 years old). Current cigarette use was examined as a potential effect modifier of the associations. Participants Participants included college students enrolled in four-year and two-year colleges in four metropolitan areas in Texas (n=5,418) who completed the survey between November 2014 and February 2015. Methods This cross-sectional study utilized mixed effects logistic regression to determine the associations between mean sensation seeking scores and ever and current e-cigarette use after controlling for covariates. Results After controlling for covariates, significant associations between sensation seeking and both ever and current e-cigarette use were observed, however, these associations were significant for non-current smokers only (AOR=1.55, 95% CI=1.39, 1.73; AOR=1.82, 95% CI=1.54, 2.15, respectively). Conclusions Sensation seeking is an important factor in identifying college students who may be at increased risk for e-cigarette use behaviors. Keywords: Electronic cigarettes, sensation seeking, current cigarette use PMID:28095126

Validation of Veterans Affairs Electronic Medical Record Smoking Data Among Iraq- and Afghanistan-Era Veterans.

PubMed

Calhoun, Patrick S; Wilson, Sarah M; Hertzberg, Jeffrey S; Kirby, Angela C; McDonald, Scott D; Dennis, Paul A; Bastian, Lori A; Dedert, Eric A; Beckham, Jean C

2017-11-01

Research using the Veterans Health Administration (VA) electronic medical records (EMR) has been limited by a lack of reliable smoking data. To evaluate the validity of using VA EMR "Health Factors" data to determine smoking status among veterans with recent military service. Sensitivity, specificity, area under the receiver-operating curve (AUC), and kappa statistics were used to evaluate concordance between VA EMR smoking status and criterion smoking status. Veterans (N = 2025) with service during the wars in Iraq/Afghanistan who participated in the VA Mid-Atlantic Post-Deployment Mental Health (PDMH) Study. Criterion smoking status was based on self-report during a confidential study visit. VA EMR smoking status was measured by coding health factors data entries (populated during automated clinical reminders) in three ways: based on the most common health factor, the most recent health factor, and the health factor within 12 months of the criterion smoking status data collection date. Concordance with PDMH smoking status (current, former, never) was highest when determined by the most commonly observed VA EMR health factor (κ = 0.69) and was not significantly impacted by psychiatric status. Agreement was higher when smoking status was dichotomized: current vs. not current (κ = 0.73; sensitivity = 0.84; specificity = 0.91; AUC = 0.87); ever vs. never (κ = 0.75; sensitivity = 0.85; specificity = 0.90; AUC = 0.87). There were substantial missing Health Factors data when restricting analyses to a 12-month period from the criterion smoking status date. Current smokers had significantly more Health Factors entries compared to never or former smokers. The use of computerized tobacco screening data to determine smoking status is valid and feasible. Results indicating that smokers have significantly more health factors entries than non-smokers suggest that caution is warranted when using the EMR to select cases for cohort studies as the risk for selection bias appears high.

Vitamin D in pregnancy: current perspectives and future directions

PubMed Central

Kiely, Mairead; Hemmingway, Andrea; O’Callaghan, Karen M.

2017-01-01

As neonatal vitamin D status is determined by circulating maternal 25-hydroxyvitamin D [25(OH)D] concentrations, prevention of maternal vitamin D deficiency during pregnancy is essential for the avoidance of neonatal deficiency. However, a high prevalence of vitamin D deficiency has been extensively reported among gravidae and neonates from ethnic minorities and white populations resident at high latitude. Currently, regulatory authorities recommend vitamin D intakes for pregnant women that are similar to non-pregnant adults of the same age, at 10–15 µg/day (400–600 IU), to meet 25(OH)D thresholds of 25–50 nmol/liter. The lack of pregnancy-specific dietary recommendations is due to inadequate data indicating whether nutritional requirements for vitamin D during pregnancy differ from the non-pregnant state. In addition, there are few dose–response studies to determine the maternal 25(OH)D response to vitamin D intake throughout pregnancy at high latitude. These data are also required to determine vitamin D requirements during pregnancy for prevention of neonatal deficiency, an outcome which is likely to require a higher maternal 25(OH)D concentration than prevention of maternal deficiency only. With regard to the impact of vitamin D on perinatal health outcomes, which could guide pregnancy-specific 25(OH)D thresholds, dietary intervention studies to date have been inconsistent and recent systematic reviews have highlighted issues of low quality and a high risk of bias as drawbacks in the trial evidence to date. Many observational studies have been hampered by a reliance on retrospective data, unclear reporting, suboptimal clinical phenotyping and incomplete subject characterization. Current investigations of vitamin D metabolism during pregnancy have potentially exciting implications for clinical research. This paper provides an update of current dietary recommendations for vitamin D in pregnant women and a synopsis of the evidence relating vitamin D status with maternal and infant health. PMID:28620423

Examining Academic Writing Motivation of Prospective Indonesian Language Teachers Using Exploratory Factor Analysis

ERIC Educational Resources Information Center

Surastina; Dedi, Fransisca S. O.

2018-01-01

Motivation determines students' success in academic writing. The current study adopted 28 items of the academic writing motivation questionnaire by Payne (2012) translated into Indonesian language to explore students' motivation in academic writing. This study involved 120 prospective Indonesian language teachers at STKIP PGRI Bandar Lampung that…

Population structure, genetic variability, and gene flow of the bean leaf beetle, Cerotoma trifurcata, in the Midwestern United States

USDA-ARS?s Scientific Manuscript database

Bean leaf beetle, Cerotoma trifurcata (Forster) (Coleoptera: Chrysomelidae), is a common pest of soybean in the Midwest. However, there are currently no studies on the genetic variability of C. trifurcata. This study examined 15-30 individuals from 25 subpopulations to determine genetic variability ...

Mass Media: The Image, Role, and Social Conditions of Women. No. 84.

ERIC Educational Resources Information Center

Ceulemans, Mieke; Fauconnier, Guido

A UNESCO-sponsored study was conducted to systematize, analyze, and evaluate the research about the interrelationships between mass media and the status of women on the basis of currently available international literature. The study sought to determine which aspects of women's media roles have been frequently researched, on which continents and…

Dimensions of Questioning: A Qualitative Study of Current Classroom Practice in Malaysia

ERIC Educational Resources Information Center

Hussin, Habsah

2006-01-01

This study investigated questioning as practiced in Malaysian secondary school classrooms, to determine teachers' rationale for adopting certain techniques of questioning, and to use the findings to inform teacher education. Questioning is a central aspect of any classroom interaction as it serves so many functions but it is still an…

Sex Differences in the Manifestation of ADHD in Emerging Adults

ERIC Educational Resources Information Center

Fedele, David A.; Lefler, Elizabeth K.; Hartung, Cynthia M.; Canu, Will H.

2012-01-01

Objective: Given the mixed literature in the area, the aim of the current study was to determine whether sex differences exist in inattention, hyperactivity, and impairment in college adults with ADHD. Method: Individuals from three universities were recruited for the study. Participants with (n = 164) and without ADHD (n = 710) completed on-line…

Career Objectives of Wyoming Secondary Students Compared with Parental Occupations.

ERIC Educational Resources Information Center

Church, Olive

The study was conducted to determine the influence of current parental occupations upon the career objectives of secondary students in Wyoming, including variables related to sex and to mother's employment. The study also sought to delineate the career clusters in which there was scant parental occupation and few students' career objectives, to…

Self-Regulation across Time of First-Generation Online Learners

ERIC Educational Resources Information Center

Barnard-Brak, Lucy; Paton, Valerie Osland; Lan, William Y.

2010-01-01

Self-regulatory skills have been associated with positive outcomes for learners. In the current study, we examined the self-regulatory skills of students who are first-generation online learners over the course of their first semester of online instruction. The purpose of this study is to determine whether the online self-regulatory skills of…

Institutional Effectiveness Assessment Process, 1993-94. Executive Summary. Hospitality and Service Occupations Division, Floristry Department.

ERIC Educational Resources Information Center

South Seattle Community Coll., Washington.

A study was conducted to determine current and former students' and local employers' satisfaction with South Seattle Community College's (SSCC's) Floristry Department. Specifically, the study gathered data related to four outcomes: that students receive an education allowing them to meet goals; that students be satisfied with facilities,…

TAFE Diploma Graduates: Personal Capital Investments and Returns

ERIC Educational Resources Information Center

van der Linde, Chris

2008-01-01

TAFE currently uses the NCVER Student Outcomes Survey (SOS) to determine outcomes related to TAFE diploma programs. The SOS measures TAFE outcomes in terms of three major categories: skills development, employment and further study. This study introduces the notion of personal capital as distinct from human capital. It argues that, while valuable,…

Personal Values and Attitudes towards Societal and Environmental Accountability: A Study of MBA Students

ERIC Educational Resources Information Center

Bhattacharyya, Asit

2016-01-01

Efforts to promote corporate societal and environmental accountability (SEA) should be informed by an understanding of stakeholders' attitudes toward enhanced accountability standards. However, little is known regarding current attitudes on this subject or the determinants of these attitudes. To address this issue, this study examines the…

Examining Learning Rates in the Evaluation of Academic Interventions That Target Reading Fluency

ERIC Educational Resources Information Center

Solomon, Benjamin G.; Poncy, Brian C.; Caravello, Devin J.; Schweiger, Emily M.

2018-01-01

The purpose of the current study is to determine whether single-case intervention studies targeting reading fluency, ranked by traditional outcome metrics (i.e., effect sizes derived from phase differences), were discrepant with rankings based on instructional efficiency, including growth per session and minutes of instruction. Converging with…

The Sleeping Medium: A Report of the Community Television Study Project, Alberta, 1971.

ERIC Educational Resources Information Center

Zelmer, A. C. L., Ed.

Conducted through a survey of several communities using videotaped interviews and an examination of the general Canadian media scene, the study undertaken for this report attempted to determine the current level of awareness and knowledge of Albertans concerning the use of cable television (CATV) for community programming. Since the study…

The Impact of Choice on EFL Students' Motivation and Engagement with L2 Vocabulary Learning

ERIC Educational Resources Information Center

Wang, Han-Chung; Huang, Hung-Tzu; Hsu, Chun-Chieh

2015-01-01

The current study investigates EFL college learners' motivation and engagement during English vocabulary learning tasks. By adopting self-determination theory (SDT; Deci & Ryan, 1985, 2000), the study looked into the impact of autonomy on college students' task motivation and engagement with vocabulary learning tasks and their general English…

Determinants of Part-Time Adult Student Participation in Education.

ERIC Educational Resources Information Center

Hawk, Thomas R.

A study was conducted to identify the factors that influence adults to continue their education by taking formal course work on a part-time basis. Using May 1981 Current Population Survey data gathered by the Bureau of the Census, the study assessed the importance of price, socioeconomic characteristics, family income, and unemployment rates in…

Automated Essay Scoring versus Human Scoring: A Correlational Study

ERIC Educational Resources Information Center

Wang, Jinhao; Brown, Michelle Stallone

2008-01-01

The purpose of the current study was to analyze the relationship between automated essay scoring (AES) and human scoring in order to determine the validity and usefulness of AES for large-scale placement tests. Specifically, a correlational research design was used to examine the correlations between AES performance and human raters' performance.…

On the Concept "Microscope": Biology Student Teachers' Cognitive Structure

ERIC Educational Resources Information Center

Kurt, Hakan; Ekici, Gulay; Aktas, Murat; Aksu, Ozlem

2013-01-01

The purpose of the current study is to determine biology student teachers' cognitive structures on the concept of microscope. Qualitative research methodology has been applied in the study. The data were collected from biology student teachers. Free word association test and drawing-writing test were used to collect data. The data collected were…

Physical Education Teacher's Attitudes towards Philosophy of Education and Technology

ERIC Educational Resources Information Center

Turkeli, Anil; Senel, Omer

2016-01-01

The current study was carried out to find out the attitudes of physical education teachers towards educational philosophy and technology, and to determine the relationship between the philosophy of education that they adopt and their attitudes toward technology. With this aim, the study was conducted on 22 female and 69 male physical education…

Effective School Board Governance Behaviors of Montana School Board Members: A Delphi Study

ERIC Educational Resources Information Center

Rocksund, Jill Ann

2017-01-01

School board governance matters. Past research has demonstrated that effective school boards are associated with higher student achievement. However, this research has been less clear about what those agreed upon effective practices are. The current study set out to identify effective school board governance practices and to determine the extent…

A Critical Question: Can We Trust Smartphone Survey Data?

ERIC Educational Resources Information Center

Tuncer, Murat

2017-01-01

The main aim of this study is to determine whether a significant difference exits among data collection with printed materials and with smart phones. The research was conducted with 282 teacher candidates who take pedagogical formation training. Three data collection tools were used throughout the study. As the results of the current research, no…

Language Learning of Children with Typical Development Using a Deductive Metalinguistic Procedure

ERIC Educational Resources Information Center

Finestack, Lizbeth H.

2014-01-01

Purpose: In the current study, the author aimed to determine whether 4- to 6-year-old typically developing children possess requisite problem-solving and language abilities to produce, generalize, and retain a novel verb inflection when taught using an explicit, deductive teaching procedure. Method: Study participants included a cross-sectional…

Science Student Teachers' Cognitive Structure on the Concept of "Food Pyramid"

ERIC Educational Resources Information Center

Çinar, Derya

2016-01-01

The current study aims to determine science student teachers' cognitive structure on the concept of food pyramid. Qualitative research method was applied in this study. Fallacies detected in the pre-service teachers' conceptual structures are believed to result in students' developing misconceptions in their future classes and will adversely…

A Study of Graduate Student Ethics in Leadership Preparation Programs

ERIC Educational Resources Information Center

Roberts, Kerry; Sampson, Pauline

2011-01-01

The ethics and character of a superintendent is important and much research has been done in this area. This study attempted to take the instrument developed by Fenstermaker (1994) and determine if future superintendents have the same ethical response as current superintendents. The small number (n=20) limited statistical comparisons. Three…

Student Perceptions and Motivation in the Classroom: Exploring Relatedness and Value

ERIC Educational Resources Information Center

Kaufman, Annette; Dodge, Tonya

2009-01-01

According to Self-Determination Theory, feelings of relatedness and value of a behavior are critical factors that affect internalization and integration. The purpose of the current study was to identify factors that influence relatedness and value in an academic setting. Specifically, the study investigated the effects of autonomy, mastery goals,…

Graduate Students' Research Interest in Business Ethics: A Study of Dissertations

ERIC Educational Resources Information Center

Piotrowski, Chris; Guyette, Roger W.

2014-01-01

Research on the nature of business ethics education during graduate-level training is somewhat limited. One approach in determining advanced students' research interest in the area is to examine the selection of "business ethics" topics for dissertation research. The current study addressed this issue by conducting a topical…

Urban Adolescents' Exercise Intentions and Behaviors: An Exploratory Study of a Trans-Contextual Model

ERIC Educational Resources Information Center

Shen, Bo; McCaughtry, Nate; Martin, Jeffrey

2008-01-01

Using a multi-theory approach, the current study was designed to identify gender differences in the psychological mechanisms by which urban adolescents' motivation in physical education transfers into their leisure-time activities. The theoretical frameworks of Self-Determination Theory and the Theory of Planned Behavior were integrated to…

The Effects of Physical Education Requirements on Physical Activity of Young Adults

ERIC Educational Resources Information Center

Mears, Derrick

2008-01-01

The purpose of this study was to determine if requiring multiple credits of high school physical education for graduation has an impact on promoting physical activity in young adults. Participants in this study (N=361) were surveyed concerning their high school physical education experiences and current performance of physical activity. Results…

Litterfall of two southern Appalachian cove hardwood forests

Treesearch

Aaron M. White; Gary L. Rolfe

2003-01-01

The current study is a component of a larger study interested in determining ecological change of the mixed-mesophytic forest from the Southern Appalachian Mountains to its far most western branches occurring in Illinois. Although there are numerous reports in the literature on litterfall, no reports were found describing litterfall within undisturbed old growth cove...

The Importance of Construct Breadth when Examining Interrole Conflict

ERIC Educational Resources Information Center

Huffman, Ann H.; Youngcourt, Satoris S.; Payne, Stephanie C.; Castro, Carl A.

2008-01-01

Research examining the influence of nonwork issues on work-related outcomes has flourished. Often, however, the breadth of the interrole conflict construct varies widely between studies. To determine if the breadth of the interrole conflict measure makes a difference, the current study compares the criterion-related validity of scores yielded by a…

The Evidence for Student-Focused Motivational Interviewing in Educational Settings: A Review of the Literature

ERIC Educational Resources Information Center

Snape, Laura; Atkinson, Cathy

2016-01-01

The current systematic literature review sought to determine the effectiveness of Motivational Interviewing (MI) in educational settings. Student-focused school-based MI (SBMI) studies were assessed using qualitative and quantitative assessment frameworks and data were reported using PRISMA guidelines. Eleven studies met the inclusion criteria,…

A Content Analysis of Nine Literacy Journals, 2009-2014

ERIC Educational Resources Information Center

Parsons, Seth A.; Gallagher, Melissa A.

2016-01-01

The purpose of this study was to determine the topics being studied, theoretical perspectives being used, and methods being implemented in current literacy research. A research team completed a content analysis of nine journals from 2009 to 2014 to gather data. In the 1,238 articles analyzed, the topics, theoretical perspectives, research designs,…

Developmental and Autism Screening: A Survey across Six States

ERIC Educational Resources Information Center

Arunyanart, Wirongrong; Fenick, Ada; Ukritchon, Supak; Imjaijitt, Worarachanee; Northrup, Veronika; Weitzman, Carol

2012-01-01

The American Academy of Pediatrics (AAP) recommends screening children for developmental delay and autism. Studies of current screening practice to date have been limited in scope and primarily focused on small, local samples. This study is designed to determine compliance with AAP screening recommendations: (1) developmental screening at 9, 18,…

The Voltage Distribution Characteristics of a Hybrid Circuit Breaker During High Current Interruption

NASA Astrophysics Data System (ADS)

Cheng, Xian; Duan, Xiongying; Liao, Minfu; Huang, Zhihui; Luo, Yan; Zou, Jiyan

2013-08-01

Hybrid circuit breaker (HCB) technology based on a vacuum interrupter and a SF6 interrupter in series has become a new research direction because of the low-carbon requirements for high voltage switches. The vacuum interrupter has an excellent ability to deal with the steep rising part of the transient recovery voltage (TRV), while the SF6 interrupter can withstand the peak part of the voltage easily. An HCB can take advantage of the interrupters in the current interruption process. In this study, an HCB model based on the vacuum ion diffusion equations, ion density equation, and modified Cassie-Mayr arc equation is explored. A simulation platform is constructed by using a set of software called the alternative transient program (ATP). An HCB prototype is also designed, and the short circuit current is interrupted by the HCB under different action sequences of contacts. The voltage distribution of the HCB is analyzed through simulations and tests. The results demonstrate that if the vacuum interrupter withstands the initial TRV and interrupts the post-arc current first, then the recovery speed of the dielectric strength of the SF6 interrupter will be fast. The voltage distribution between two interrupters is determined by their post-arc resistance, which happens after current-zero, and subsequently, it is determined by the capacitive impedance after the post-arc current decays to zero.

Pitch ranking, electrode discrimination, and physiological spread of excitation using current steering in cochlear implants

PubMed Central

Goehring, Jenny L.; Neff, Donna L.; Baudhuin, Jacquelyn L.; Hughes, Michelle L.

2014-01-01

The first objective of this study was to determine whether adaptive pitch-ranking and electrode-discrimination tasks with cochlear-implant (CI) recipients produce similar results for perceiving intermediate “virtual-channel” pitch percepts using current steering. Previous studies have not examined both behavioral tasks in the same subjects with current steering. A second objective was to determine whether a physiological metric of spatial separation using the electrically evoked compound action potential spread-of-excitation (ECAP SOE) function could predict performance in the behavioral tasks. The metric was the separation index (Σ), defined as the difference in normalized amplitudes between two adjacent ECAP SOE functions, summed across all masker electrodes. Eleven CII or 90 K Advanced Bionics (Valencia, CA) recipients were tested using pairs of electrodes from the basal, middle, and apical portions of the electrode array. The behavioral results, expressed as d′, showed no significant differences across tasks. There was also no significant effect of electrode region for either task. ECAP Σ was not significantly correlated with pitch ranking or electrode discrimination for any of the electrode regions. Therefore, the ECAP separation index is not sensitive enough to predict perceptual resolution of virtual channels. PMID:25480063

Measuring the acoustoelectric interaction constant using ultrasound current source density imaging

NASA Astrophysics Data System (ADS)

Li, Qian; Olafsson, Ragnar; Ingram, Pier; Wang, Zhaohui; Witte, Russell

2012-10-01

Ultrasound current source density imaging (UCSDI) exploits the acoustoelectric (AE) effect, an interaction between ultrasound pressure and electrical resistivity, to map electrical conduction in the heart. The conversion efficiency for UCSDI is determined by the AE interaction constant K, a fundamental property of all materials; K directly affects the magnitude of the detected voltage signal in UCSDI. This paper describes a technique for measuring K in biological tissue, and reports its value for the first time in cadaver hearts. A custom chamber was designed and fabricated to control the geometry for estimating K, which was measured in different ionic salt solutions and seven cadaver rabbit hearts. We found K to be strongly dependent on concentration for the divalent salt CuSO4, but not for the monovalent salt NaCl, consistent with their different chemical properties. In the rabbit heart, K was determined to be 0.041±0.012%/MPa, similar to the measurement of K in physiological saline (0.034±0.003%/MPa). This study provides a baseline estimate of K for modeling and experimental studies that involve UCSDI to map cardiac conduction and reentry currents associated with arrhythmias.

Factors in Sustainable Development: Current and Innovative Livestock and Range Management Practices as Perceived by Cattle-Producing Ejidatarios and Private Cattle Ranchers of Sonora, Mexico. A Summary Report of Research. Department Information Bulletin 99-4.

ERIC Educational Resources Information Center

Hamlett, Peggy J.

A study was conducted to identify and compare livestock production and range management practices currently in use in the Texas/Mexico border corridor, and to determine the acceptance of selected innovative practices among cattle ranchers in the State of Sonora, Mexico. Information was collected from private livestock producers who were members of…

Hydrogen production econometric studies. [hydrogen and fossil fuels

NASA Technical Reports Server (NTRS)

Howell, J. R.; Bannerot, R. B.

1975-01-01

The current assessments of fossil fuel resources in the United States were examined, and predictions of the maximum and minimum lifetimes of recoverable resources according to these assessments are presented. In addition, current rates of production in quads/year for the fossil fuels were determined from the literature. Where possible, costs of energy, location of reserves, and remaining time before these reserves are exhausted are given. Limitations that appear to hinder complete development of each energy source are outlined.

Current rates of publication for podium and poster presentations at the american society for surgery of the hand annual meetings.

PubMed

Abzug, Joshua M; Osterman, Meredith; Rivlin, Michael; Paryavi, Ebrahim; Osterman, A Lee

2014-09-01

Research projects are presented at the Annual Meetings of the American Society for Surgery of the Hand (ASSH). It is unknown how many achieve publication in peer-reviewed journals. We sought to determine current rates of publication of podium and poster presentations. All ASSH podium and poster presentations from 2000 to 2005 were reviewed, and an Internet-based search using PubMed and Google was conducted to determine whether the presented studies had been published. Times to publication and journal names were recorded. Data were analyzed with descriptive statistics. Fisher's exact test was conducted to compare current trends with previous trends. Of 1127 podium and poster presentations reviewed, 46% were published in peer-reviewed journals. Forty-seven percent of published presentations (242 presentations) were in Journal of Hand Surgery, and 11% (59 presentations) were in Journal of Bone and Joint Surgery. Forty-five percent of presentations were published within 2 years and 66% within 3 years. The publication rate for podium presentations was significantly higher than that previously reported for Journal of Hand Surgery, at 54% compared with 44% (P=0.004). Currently, fewer than half of the studies presented at Annual Meetings of the ASSH achieve publication in peer-reviewed journals. Presentations are most likely to be published within 3 years, and almost half are published in Journal of Hand Surgery.

Temperature sensitivity study of eddy current and digital gauge probes for nuclear fuel rod oxide measurement

NASA Astrophysics Data System (ADS)

Beck, Faith R.; Lind, R. Paul; Smith, James A.

2018-04-01

Novel fuels are part of the nationwide effort to reduce the enrichment of Uranium for energy production. Performance of such fuels is determined by irradiating their surfaces. To test irradiated samples, the instrumentation must operate remotely. The plate checker used in this experiment at Idaho National Lab (INL) performs non-destructive testing on fuel rod and plate geometries with two different types of sensors: eddy current and digital thickness gauges. The sensors measure oxide growth and total sample thickness on research fuels, respectively. Sensor measurement accuracy is crucial because even 10 microns of error is significant when determining the viability of an experimental fuel. One parameter known to affect the eddy current and thickness gauge sensors is temperature. Since both sensor accuracies depend on the ambient temperature of the system, the plate checker has been characterized for these sensitivities. The manufacturer of the digital gauge probes has noted a rather large coefficient of thermal expansion for their linear scale. It should also be noted that the accuracy of the digital gauge probes are specified at 20°C, which is approximately 7°C cooler than the average hot-cell temperature. In this work, the effect of temperature on the eddy current and digital gauge probes is studied, and thickness measurements are given as empirical functions of temperature.

Flood-inundation maps for the Tippecanoe River at Winamac, Indiana

USGS Publications Warehouse

Menke, Chad D.; Bunch, Aubrey R.

2015-09-25

For this study, flood profiles were computed for the Tippecanoe River reach by means of a one-dimensional step-backwater model. The hydraulic model was calibrated by using the most current stage-discharge relations at the Tippecanoe River streamgage, in combination with the current (2014) Federal Emergency Management Agency flood-insurance study for Pulaski County. The calibrated hydraulic model was then used to determine nine water-surface profiles for flood stages at 1-foot intervals referenced to the streamgage datum and ranging from bankfull to the highest stage of the current stage-discharge rating curve. The 1-percent annual exceedance probability (AEP) flood stage (flood with recurrence intervals within 100 years) has not been determined yet for this streamgage location. The rating has not been developed for the 1-percent AEP because the streamgage dates to only 2001. The simulated water-surface profiles were then used with a geographic information system (GIS) digital elevation model (DEM, derived from Light Detection and Ranging [lidar]) in order to delineate the area flooded at each water level. The availability of these maps, along with Internet information regarding current stage from the USGS streamgage 03331753, Tippecanoe River at Winamac, Ind., and forecast stream stages from the NWS AHPS, provides emergency management personnel and residents with information that is critical for flood response activities such as evacuations and road closures, as well as for post-flood recovery efforts.

Sensitivity Study of the Wall Interference Correction System (WICS) for Rectangular Tunnels

NASA Technical Reports Server (NTRS)

Walker, Eric L.; Everhart, Joel L.; Iyer, Venkit

2001-01-01

An off-line version of the Wall Interference Correction System (WICS) has been implemented for the NASA Langley National Transonic Facility. The correction capability is currently restricted to corrections for solid wall interference in the model pitch plane for Mach numbers less than 0.45 due to a limitation in tunnel calibration data. A study to assess output sensitivity to measurement uncertainty was conducted to determine standard operational procedures and guidelines to ensure data quality during the testing process. Changes to the current facility setup and design recommendations for installing the WICS code into a new facility are reported.

Comparison of Several Methods for Determining the Internal Resistance of Lithium Ion Cells

PubMed Central

Schweiger, Hans-Georg; Obeidi, Ossama; Komesker, Oliver; Raschke, André; Schiemann, Michael; Zehner, Christian; Gehnen, Markus; Keller, Michael; Birke, Peter

2010-01-01

The internal resistance is the key parameter for determining power, energy efficiency and lost heat of a lithium ion cell. Precise knowledge of this value is vital for designing battery systems for automotive applications. Internal resistance of a cell was determined by current step methods, AC (alternating current) methods, electrochemical impedance spectroscopy and thermal loss methods. The outcomes of these measurements have been compared with each other. If charge or discharge of the cell is limited, current step methods provide the same results as energy loss methods. PMID:22219678

Calcium channel currents in bovine adrenal chromaffin cells and their modulation by anaesthetic agents.

PubMed Central

Charlesworth, P; Pocock, G; Richards, C D

1994-01-01

1. The calcium channel currents of bovine adrenal chromaffin cells were characterized using a variety of voltage pulse protocols and selective channel blockers before examination of their modulation by anaesthetic agents. 2. All the anaesthetics studied (halothane, methoxyflurane, etomidate and methohexitone) inhibited the calcium channel currents in a concentration-dependent manner and increased the rate of current decay. 3. The anaesthetics did not shift the current-voltage relation nor did they change the voltage for half-maximal channel activation derived from analysis of the voltage dependence of the tail currents. None of the anaesthetics appeared to alter the time constant of tail current decay. 4. To complement earlier studies of the inhibitory actions of anaesthetics on K(+)-evoked catecholamine secretion and the associated Ca2+ uptake, the IC50 values for etomidate and methohexitone were determined using a biochemical assay. The IC50 values for anaesthetic inhibition of calcium channel currents corresponded closely with those for inhibition of K(+)-evoked calcium uptake and catecholamine secretion. 5. The inhibitory effect of the volatile anaesthetics and etomidate is best explained by dual action: a reduction in the probability of channel opening coupled with an increase in the rate of channel inactivation. Methohexitone appeared to inhibit the currents by a use-dependent slow block. PMID:7707224

ICan: An Optimized Ion-Current-Based Quantification Procedure with Enhanced Quantitative Accuracy and Sensitivity in Biomarker Discovery

PubMed Central

2015-01-01

The rapidly expanding availability of high-resolution mass spectrometry has substantially enhanced the ion-current-based relative quantification techniques. Despite the increasing interest in ion-current-based methods, quantitative sensitivity, accuracy, and false discovery rate remain the major concerns; consequently, comprehensive evaluation and development in these regards are urgently needed. Here we describe an integrated, new procedure for data normalization and protein ratio estimation, termed ICan, for improved ion-current-based analysis of data generated by high-resolution mass spectrometry (MS). ICan achieved significantly better accuracy and precision, and lower false-positive rate for discovering altered proteins, over current popular pipelines. A spiked-in experiment was used to evaluate the performance of ICan to detect small changes. In this study E. coli extracts were spiked with moderate-abundance proteins from human plasma (MAP, enriched by IgY14-SuperMix procedure) at two different levels to set a small change of 1.5-fold. Forty-five (92%, with an average ratio of 1.71 ± 0.13) of 49 identified MAP protein (i.e., the true positives) and none of the reference proteins (1.0-fold) were determined as significantly altered proteins, with cutoff thresholds of ≥1.3-fold change and p ≤ 0.05. This is the first study to evaluate and prove competitive performance of the ion-current-based approach for assigning significance to proteins with small changes. By comparison, other methods showed remarkably inferior performance. ICan can be broadly applicable to reliable and sensitive proteomic survey of multiple biological samples with the use of high-resolution MS. Moreover, many key features evaluated and optimized here such as normalization, protein ratio determination, and statistical analyses are also valuable for data analysis by isotope-labeling methods. PMID:25285707

Social support and social network as intermediary social determinants of dental caries in adolescents.

PubMed

Fontanini, Humberto; Marshman, Zoe; Vettore, Mario

2015-04-01

The aim of this study was to investigate the association between intermediary social determinants, namely social support and social network with dental caries in adolescents. An adapted version of the WHO social determinants of health conceptual framework was used to organize structural and intermediary social determinants of dental caries into six blocks including perceived social support and number of social networks. A cross-sectional study was conducted with a representative sample of 542 students between 12 and 14 years of age in public schools located in the city of Dourados, Brazil in 2012. The outcome variables were caries experience (DMFT ≥ 1) and current dental caries (component D of DMFT ≥ 1) recorded by a calibrated dentist. Individual interviews were performed to collect data on perceived social support and numbers of social networks from family and friends and covariates. Multivariate Poisson regressions using hierarchical models were conducted. The prevalence of adolescents with caries experience and current dental caries was 55.2% and 32.1%, respectively. Adolescents with low numbers of social networks and low levels of social support from family (PR 1.47; 95% CI = 1.01-2.14) were more likely to have DMFT ≥ 1. Current dental caries was associated with low numbers of social networks and low levels of social support from family (PR 2.26; 95% CI = 1.15-4.44). Social support and social network were influential psychosocial factors to dental caries in adolescents. This finding requires confirmation in other countries but potentially has implications for programmes to promote oral health. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Stratified flows in complex terrain

NASA Astrophysics Data System (ADS)

Retallack, Charles

The focus of this dissertation is the study of stratified atmospheric flows in the presence of complex terrain. Two large-scale field study campaigns were carried out, each with a focus on a specific archetypal terrain. Each field study involved the utilization of remote and in-situ atmospheric monitoring devices to collect experimental data. The first of the two field studies focused on pollution transport mechanisms near an escarpment. The analysis aimed to determine the combined effect of the escarpment and ambient density stratification on the flow and aerosol pollution transport. It was found that under specific atmospheric conditions, the escarpment prompted the channeling, down-mixing, and trapping of aerosol pollutant plumes. The objective of the second field campaign was the study of stratified flows in a mountain valley. Analysis revealed that buoyancy driven katabatic currents originating on the surrounding valley slopes created a scenario in which a down-slope gravity current transitioned into an intrusive gravity current. The intrusive gravity current propagated near the interface of a density stratified lower ambient layer and a non-stratified upper ambient layer. A combination of shallow water theory and energy arguments is used to produce a model for the propagation of a gravity current moving along the interface of a homogeneous ambient layer and a linearly stratified layer. It is found that the gravity current propagating entirely within the homogeneous layer travels at the greatest speed. As the relative density of the gravity current is increased, the gravity current begins to slump below the interface of the two layers and the propagation speed decreases.

Excitation system for rotating synchronous machines

DOEpatents

Umans, Stephen D.; Driscoll, David J.

2002-01-01

A system for providing DC current to a rotating superconducting winding is provided. The system receives current feedback from the superconducting winding and determines an error signal based on the current feedback and a reference signal. The system determines a control signal corresponding to the error signal and provides a positive and negative superconducting winding excitation voltage based on the control signal.

Potentiometric determination of trypsin using a polymeric membrane polycation-sensitive electrode based on current-controlled reagent delivery.

PubMed

Chen, Yan; Ding, Jiawang; Qin, Wei

2012-12-01

A potentiometric biosensor for the determination of trypsin is described based on current-controlled reagent delivery. A polymeric membrane protamine-sensitive electrode with dinonylnaphthalene sulfonate as cation exchanger is used for in situ generation of protamine. Diffusion of protamine across the polymeric membrane can be controlled precisely by applying an external current. The hydrolysis catalyzed with trypsin in sample solution decreases the concentration of free protamine released at the sample-membrane interface and facilitates the stripping of protamine out of the membrane surface via the ion-exchange process with sodium ions from the sample solution, thus decreasing the membrane potential, by which the protease can be sensed potentiometrically. The influences of anodic current amplitude, current pulse duration and protamine concentration in the inner filling solution on the membrane potential response have been studied. Under optimum conditions, the proposed protamine-sensitive electrode is useful for continuous and reversible detection of trypsin over the concentration range of 0.5-5UmL(-1) with a detection limit of 0.3UmL(-1). The proposed detection strategy provides a rapid and reagentless way for the detection of protease activities and offers great potential in the homogeneous immunoassays using proteases as labels. Copyright © 2012 Elsevier B.V. All rights reserved.

What is the optimal anodal electrode position for inducing corticomotor excitability changes in transcranial direct current stimulation?

PubMed

Lee, Minji; Kim, Yun-Hee; Im, Chang-Hwan; Kim, Jung-Hoon; Park, Chang-hyun; Chang, Won Hyuk; Lee, Ahee

2015-01-01

Transcranial direct current stimulation (tDCS) non-invasively modulates brain function by inducing neuronal excitability. The conventional hot spot for inducing the highest current density in the hand motor area may not be the optimal site for effective stimulation. In this study, we investigated the influence of the center position of the anodal electrode on changes in motor cortical excitability. We considered three tDCS conditions in 16 healthy subjects: (i) real stimulation with the anodal electrode located at the conventional hand motor hot spot determined by motor evoked potentials (MEPs); (ii) real stimulation with the anodal electrode located at the point with the highest current density in the hand motor area as determined by electric current simulation; and (iii) sham stimulation. Motor cortical excitability as measured by MEP amplitude increased after both real stimulation conditions, but not after sham stimulation. Stimulation using the simulation-derived anodal electrode position, which was found to be posterior to the MEP hot spot for all subjects, induced higher motor cortical excitability. Individual positioning of the anodal electrode, based on the consideration of anatomical differences between subjects, appears to be important for maximizing the effects of tDCS. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Age-related changes of nasal cavity and conchae volumes and volume fractions in children: a stereological study.

PubMed

Ertekin, T; Değermenci, M; Nisari, M; Unur, E; Coşkun, A

2016-01-01

The anatomy of the human nasal cavity (NC) is complex and its structures are closely related to the functions of the NC. Studies which assessing the mean volumes of NC and conchae are very infrequent. The purpose of current study is to investigate development of NC and conchae according to age and sex by using stereological method. This retrospective volumetric study was carried out on 342 individuals (166 females and 176 males) between 0 and 18 years old with no pathological conditions or medical procedures that affected the skeletal morphology of the NC. Volumetric estimations were determined on computed tomography (CT) images using point-counting approach of stereological methods. NC, inferior nasal conchae (INC) and middle nasal conchae (MNC) volume measurements that obtained using point-counting method were increased with age in both sexes until 15 years old. Regardless of gender; no significant difference was determined between the left and right values for NC, conchae volumes and choanae measurements. Generally, significant differences were determined in NC and INC volumes according to gender after they reached maximum growth period. According to age the volume ratios of INC to NC and MNC to NC were ranged from 18% to 32% and 9% to15%, respectively. The current study demonstrated that the point-counting method is effective in determining volume estimation of NC and is well suited for CT studies. Our results could provide volumetric indexes for the NC and conchae, which could help the physician for both patient selections for surgery, and for the assessment of any surgical technique used to treatment of nasal obstruction. (.

Critical Endowment Policy Issues

ERIC Educational Resources Information Center

Lapovsky, Lucie

2007-01-01

Governing boards and administrations wrestle with complex endowment policy decisions that will determine current institutional quality and future institutional viability. This chapter presents data from the 2006 NACUBO Endowment Study (published in 2007), divided into the following issues of endowment management: historical returns; endowment…

Toward a New Industrial America.

ERIC Educational Resources Information Center

Berger, Suzanne; And Others

1989-01-01

Summarizes the positive and negative sides of American industrial practices determined by the Commission on Industrial Productivity at the Massachusetts Institute of Technology. Describes five imperatives recommended by the commission based on its study of current weakness and best practices in American industry. (YP)

Patterns of host adaptation in Frankliniella occidentalis among vegetable crops

USDA-ARS?s Scientific Manuscript database

The current study examined the variation in life table characteristics, and physiological, biochemical, and molecular bases of western flower thrips, Frankliniella occidentalis (Pergande) host adaptation patterns. The main objective was to determine whether host availability affects insect preferenc...

The Views of Mathematics Teachers on the Factors Affecting the Integration of Technology in Mathematics Courses

ERIC Educational Resources Information Center

Kaleli-Yilmaz, Gül

2015-01-01

The aim of this study was to determine the views of mathematics teachers on the factors that affect the integration of technology in mathematic courses. It is a qualitative case study. The sample size of the study is 10 teachers who are receiving postgraduate education in a university in Turkey. The current study was conducted in three stages. At…

Climate change, extinction risks, and reproduction of terrestrial vertebrates.

PubMed

Carey, Cynthia

2014-01-01

This review includes a broad, but superficial, summary of our understanding about current and future climate changes, the predictions about how these changes will likely affect the risks of extinction of organisms, and how current climate changes are already affecting reproduction in terrestrial vertebrates. Many organisms have become extinct in the last century, but habitat destruction, disease and man-made factors other than climate change have been implicated as the causal factor in almost all of these. Reproduction is certain to be negatively impacted in all vertebrate groups for a variety of reasons, such as direct thermal and hydric effects on mortality of embryos, mismatches between optimal availability of food supplies, frequently determined by temperature, and reproductive capacities, sometimes determined by rigid factors such as photoperiod, and disappearance of appropriate foraging opportunities, such as melting sea ice. The numbers of studies documenting correlations between climate changes and biological phenomena are rapidly increasing, but more direct information about the consequences of these changes for species survival and ecosystem health is needed than is currently available.

Comparative study of methods to measure the density of Cementious powders

PubMed Central

Helsel, Michelle A.; Bentz, Dale

2016-01-01

The accurate measurement of the density of hydraulic cement has an essential role in the determination of concrete mixture proportions. As more supplementary cementitious materials (SCM), such as fly ash, and slag, or cement replacements materials such as limestone and calcium carbonate are used in blended cements, knowledge of the density of each powder or of the blended cement would allow a more accurate calculation of the proportions of a concrete mixture by volume instead of by mass. The current ASTM standard for measuring cement density is the “Test Method for Density of Hydraulic Cements” (ASTM C188-14), which utilizes a liquid displacement method to measure the volume of the cement. This paper will examine advantageous modifications of the current ASTM test, by alcohol substitutions for kerosene. In addition, a gas (helium) pycnometry method is evaluated as a possible alternative to the current standard. The described techniques will be compared to determine the most precise and reproducible method for measuring the density of hydraulic cements and other powders. PMID:27099404

Comparing hardcopy and softcopy results in the study of the impact of workflow on perceived reproduction quality of fine art images

NASA Astrophysics Data System (ADS)

Farnand, Susan; Jiang, Jun; Frey, Franziska

2011-01-01

A project, supported by the Andrew W. Mellon Foundation, is currently underway to evaluate current practices in fine art image reproduction, determine the image quality generally achievable, and establish a suggested framework for art image interchange. To determine the image quality currently being achieved, experimentation has been conducted in which a set of objective targets and pieces of artwork in various media were imaged by participating museums and other cultural heritage institutions. Prints and images for display made from the delivered image files at the Rochester Institute of Technology were used as stimuli in psychometric testing in which observers were asked to evaluate the prints as reproductions of the original artwork and as stand alone images. The results indicated that there were limited differences between assessments made using displayed images relative to printed reproductions. Further, the differences between rankings made with and without the original artwork present were much smaller than expected.

Evaluation of metal-foil strain gages for cryogenic application in magnetic fields

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

Freynik, H.S. Jr.; Roach, D.R.; Deis, D.W.

1977-07-08

The requirement for the design and construction of large superconducting magnet systems for fusion research has raised a number of new questions regarding the properties of composite superconducting conductors. One of these, the effect of mechanical stress on the current-carrying capacity of Nb/sub 3/Sn, is of major importance in determining the feasibility of constructing large magnets with this material. A typical experiment for determining such data involves the measurement of critical current versus magnetic field while the conductor is being mechanically strained to various degrees. Techniques are well developed for the current and field measurements, but much less so formore » the accurate measurement of strain at liquid-helium temperature in a high magnetic field. A study was made of commercial, metal-foil strain gages for use under these conditions. The information developed can also be applied to the use of strain gages as diagnostic tools in superconducting magnets.« less

Comparative study of methods to measure the density of Cementious powders.

PubMed

Helsel, Michelle A; Ferraris, Chiara F; Bentz, Dale

2016-11-01

The accurate measurement of the density of hydraulic cement has an essential role in the determination of concrete mixture proportions. As more supplementary cementitious materials (SCM), such as fly ash, and slag, or cement replacements materials such as limestone and calcium carbonate are used in blended cements, knowledge of the density of each powder or of the blended cement would allow a more accurate calculation of the proportions of a concrete mixture by volume instead of by mass. The current ASTM standard for measuring cement density is the "Test Method for Density of Hydraulic Cements" (ASTM C188-14), which utilizes a liquid displacement method to measure the volume of the cement. This paper will examine advantageous modifications of the current ASTM test, by alcohol substitutions for kerosene. In addition, a gas (helium) pycnometry method is evaluated as a possible alternative to the current standard. The described techniques will be compared to determine the most precise and reproducible method for measuring the density of hydraulic cements and other powders.

Graduates' Transition from Study to Employment of Radiologic Technology Graduates of the Lyceum University of the Philippines--Batangas

ERIC Educational Resources Information Center

Valdez, Anacleta P.

2012-01-01

A ten-year tracer study of Radiologic Technology graduates of Lyceum of the Philippines University SY 1997-2007 using a survey-structured questionnaire was conducted to examine retrospective contribution of their education to their current work. The objectives of the study included the determination of graduates' job-placement profile; how…

Understory Plant Community Response to Season of Burn in Natural Longleaf Pine Forests

Treesearch

John S. Kush; Ralph S. Meldahl; William D. Boyer

2000-01-01

A season of burn study was initiated in 1973 on the Escambia Experimental Forest, near Brewton, Alabama. All study plots were established in the 14-year-old longleaf pine (Pinus palustris) stands. Treatments consisted of biennial burns in winter, spring, and summer, plus a no-burn check. Objectives of the current study were to determine...

Early Markers of Autism Spectrum Disorders in Infants and Toddlers Prospectively Identified in the Social Attention and Communication Study

ERIC Educational Resources Information Center

Barbaro, Josephine; Dissanayake, Cheryl

2013-01-01

The Social Attention and Communication Study involved the successful implementation of developmental surveillance of the early markers of autism spectrum disorders in a community-based setting. The objective in the current study was to determine the most discriminating and predictive markers of autism spectrum disorders used in the Social…

National Study of Word Processing Installations in Selected Business Organizations. A Report on the National Word Processing Research Study of Delta Pi Epsilon.

ERIC Educational Resources Information Center

Scriven, Jolene D.; And Others

A study was conducted (1) to determine current practices in word processing installations in selected organizations throughout the United States, and (2) to ascertain anticipated future developments in word processing as well as to provide recommendations for educational institutions that prepare workers for business offices. Seven interview…

Exploring Turkish Preservice Teachers' Mental Models of the Environment: Are They Related to Gender and Academic Level?

ERIC Educational Resources Information Center

Ahi, Berat; Balci, Sibel; Alisinanoglu, Fatma

2017-01-01

The current study aimed to establish Turkish preservice teachers' mental models of the environment and to determine the relationship these models have with gender and grade level. The study group comprised 463 Turkish preservice teachers from primary school education and preschool education departments. The data from the study were collected from…

Attitudes toward Foreign Language Study and Requirements in American Schools and Colleges: Results of a National Survey.

ERIC Educational Resources Information Center

Eddy, Peter A.

1979-01-01

Reports the results of a national survey conducted in the US to determine: (1) languages used in the home, (2) second languages learned, (3) current use of second language, (4) attitudes toward the worth of second language study, and (5) opinions about the opportunity and requirement to study languages at various educational levels. (AM)

Asset surveillance system: apparatus and method

NASA Technical Reports Server (NTRS)

Bickford, Randall L. (Inventor)

2007-01-01

System and method for providing surveillance of an asset comprised of numerically fitting at least one mathematical model to obtained residual data correlative to asset operation; storing at least one mathematical model in a memory; obtaining a current set of signal data from the asset; retrieving at least one mathematical model from the memory, using the retrieved mathematical model in a sequential hypothesis test for determining if the current set of signal data is indicative of a fault condition; determining an asset fault cause correlative to a determined indication of a fault condition; providing an indication correlative to a determined fault cause, and an action when warranted. The residual data can be mode partitioned, a current mode of operation can be determined from the asset, and at least one mathematical model can be retrieved from the memory as a function of the determined mode of operation.

Maximizing ion current rectification in a bipolar conical nanopore fluidic diode using optimum junction location.

PubMed

Singh, Kunwar Pal

2016-10-12

The ion current rectification has been obtained as a function of the location of a heterojunction in a bipolar conical nanopore fluidic diode for different parameters to determine the junction location for maximum ion current rectification using numerical simulations. Forward current peaks for a specific location of the junction and reverse current decreases with the junction location due to a change in ion enrichment/depletion in the pore. The optimum location of the heterojunction shifts towards the tip with base/tip diameter and surface charge density, and towards the base with the electrolyte concentration. The optimum location of the heterojunction has been approximated by an equation as a function of pore length, base/tip diameter, surface charge density and electrolyte concentration. The study is useful to design a rectifier with maximum ion current rectification for practical purposes.

Gender differences in the causal direction between workplace harassment and drinking.

PubMed

Freels, Sally A; Richman, Judith A; Rospenda, Kathleen M

2005-08-01

Data from a longitudinal study of university employees across four waves is used to determine the extent to which workplace harassment predicts drinking or conversely the extent to which drinking predicts workplace harassment, and to address gender differences in these relationships. Mixed effects regression models are used to test the effects of 1) harassment at the previous wave on drinking at the current wave, adjusting for drinking at the previous wave, and 2) drinking at the previous wave on harassment at the current wave, adjusting for harassment at the previous wave. For males, drinking at the previous wave predicts sexual harassment at the current wave, whereas for females, sexual harassment at the previous wave predicts drinking at the current wave.

Spontaneous recombination current in InGaAs/GaAs quantum well lasers

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

Blood, P.; Fletcher, E.D.; Woodbridge, K.

1990-10-08

We have studied the intrinsic factors which determine the threshold current and its temperature dependence in 160-A-wide In{sub 0.2}Ga{sub 0.8}As single well quantum lasers with GaAs barriers, grown by molecular beam epitaxy on GaAs substrates. By measuring the relative temperature dependence of the spontaneous emission intensity at threshold we show that radiative transitions between higher order ({ital n}=2,3) electron and heavy hole subbands make a significant contribution to the threshold current and its temperature sensitivity, even in devices where the laser transitions are between {ital n}=1 subbands. These higher transitions will also influence the dependence of threshold current and itsmore » temperature sensitivity on well width.« less

Eddy Current System for Material Inspection and Flaw Visualization

NASA Technical Reports Server (NTRS)

Bachnak, R.; King, S.; Maeger, W.; Nguyen, T.

2007-01-01

Eddy current methods have been successfully used in a variety of non-destructive evaluation applications including detection of cracks, measurements of material thickness, determining metal thinning due to corrosion, measurements of coating thickness, determining electrical conductivity, identification of materials, and detection of corrosion in heat exchanger tubes. This paper describes the development of an eddy current prototype that combines positional and eddy-current data to produce a C-scan of tested material. The preliminary system consists of an eddy current probe, a position tracking mechanism, and basic data visualization capability. Initial test results of the prototype are presented in this paper.

Determinants of Subjective Social Status and Health Among Latin American Women Immigrants in Spain: A Qualitative Approach.

PubMed

Sanchón-Macias, Ma Visitación; Bover-Bover, Andreu; Prieto-Salceda, Dolores; Paz-Zulueta, María; Torres, Blanca; Gastaldo, Denise

2016-04-01

This qualitative study was carried out to better understand factors that determine the subjective social status of Latin Americans in Spain. The study was conducted following a theoretical framework and forms part of broader study on subjective social status and health. Ten immigrant participants engaged in semi-structured interviews, from which data were collected. The study results show that socioeconomic aspects of the crisis and of policies adopted have shaped immigrant living conditions in Spain. Four major themes that emerged from the analysis were related to non-recognition of educational credentials, precarious working conditions, unemployment and loneliness. These results illustrate the outcomes of current policies on health and suggest a need for health professionals to orient practices toward social determinants, thus utilizing evaluations of subjective social status to reduce inequalities in health.

Determination of the Kwall correction factor for a cylindrical ionization chamber to measure air-kerma in 60Co gamma beams.

PubMed

Laitano, R F; Toni, M P; Pimpinella, M; Bovi, M

2002-07-21

The factor Kwall to correct for photon attenuation and scatter in the wall of ionization chambers for 60Co air-kerma measurement has been traditionally determined by a procedure based on a linear extrapolation of the chamber current to zero wall thickness. Monte Carlo calculations by Rogers and Bielajew (1990 Phys. Med. Biol. 35 1065-78) provided evidence, mostly for chambers of cylindrical and spherical geometry, of appreciable deviations between the calculated values of Kwall and those obtained by the traditional extrapolation procedure. In the present work an experimental method other than the traditional extrapolation procedure was used to determine the Kwall factor. In this method the dependence of the ionization current in a cylindrical chamber was analysed as a function of an effective wall thickness in place of the physical (radial) wall thickness traditionally considered in this type of measurement. To this end the chamber wall was ideally divided into distinct regions and for each region an effective thickness to which the chamber current correlates was determined. A Monte Carlo calculation of attenuation and scatter effects in the different regions of the chamber wall was also made to compare calculation to measurement results. The Kwall values experimentally determined in this work agree within 0.2% with the Monte Carlo calculation. The agreement between these independent methods and the appreciable deviation (up to about 1%) between the results of both these methods and those obtained by the traditional extrapolation procedure support the conclusion that the two independent methods providing comparable results are correct and the traditional extrapolation procedure is likely to be wrong. The numerical results of the present study refer to a cylindrical cavity chamber like that adopted as the Italian national air-kerma standard at INMRI-ENEA (Italy). The method used in this study applies, however, to any other chamber of the same type.

Previous success and current body condition determine breeding propensity in Lesser Scaup: evidence for the individual heterogeneity hypothesis

USGS Publications Warehouse

Warren, Jeffrey M.; Cutting, Kyle A.; Takekawa, John Y.; De La Cruz, Susan E. W.; Williams, Tony D.; Koons, David N.

2014-01-01

The decision to breed influences an individual's current and future reproduction, and the proportion of individuals that breed is an important determinant of population dynamics. Age, experience, individual quality, and environmental conditions have all been demonstrated to influence breeding propensity. To elucidate which of these factors exerts the greatest influence on breeding propensity in a temperate waterfowl, we studied female Lesser Scaup (Aythya affinis) breeding in southwestern Montana. Females were captured during the breeding seasons of 2007–2009, and breeding status was determined on the basis of (1) presence of an egg in the oviduct or (2) blood plasma vitellogenin (VTG) levels. Presence on the study site in the previous year, a proxy for adult female success, was determined with stable isotope signatures of a primary feather collected at capture. Overall, 57% of females had evidence of breeding at the time of capture; this increased to 86% for females captured on or after peak nest initiation. Capture date and size-adjusted body condition positively influenced breeding propensity, with a declining body-condition threshold through the breeding season. We did not detect an influence of age on breeding propensity. Drought conditions negatively affected breeding propensity, reducing the proportion of breeding females to 0.85 (SE = 0.05) from 0.94 (SE = 0.03) during normal-water years. A female that was present in the previous breeding season was 5% more likely to breed than a female that was not present then. The positive correlation between age and experience makes it difficult to differentiate the roles of age, experience, and individual quality in reproductive success in vertebrates. Our results indicate that individual quality, as expressed by previous success and current body condition, may be among the most important determinants of breeding propensity in female Lesser Scaup, providing further support for the individual heterogeneity hypothesis.

Using Passive Two-Port Networks to Study the Forced Vibrations of Piezoceramic Transducers

NASA Astrophysics Data System (ADS)

Karlash, V. L.

2017-09-01

A generalization and subsequent development of experimental techniques, including methods of studying the phase-frequency relations between the measured components of admittance and instantaneous power are considered. The conditions of electric loading where electric currents, voltages, or instantaneous powers of constant amplitude in the piezoresonators are specified are numerically modeled. It is particularly established that the advanced Mason circuit with additional switch allows acquiring much more data on the forced vibrations of piezoceramic transducers than the classical circuit. The measured (at an arbitrary frequency) voltage drop across the piezoelement, its pull-up resistor, and at the input of the measuring circuit allow determining, with high accuracy, the current, conductivity, impedance, instantaneous power, and phase shifts when the amplitudes of electric current and voltage are given.

Recent progress on preparation and properties of nanocomposites from recycled polymers: a review.

PubMed

Zare, Yasser

2013-03-01

Currently, the growing consumption of polymer products creates the large quantities of waste materials resulting in public concern in the environment and people life. Nanotechnology is assumed the important technology in the current century. Recently, many researchers have tried to develop this new science for polymer recycling. In this article, the application of different nanofillers in the recycled polymers such as PET, PP, HDPE, PVC, etc. and the attributed composites and blends is studied. The morphological, mechanical, rheological and thermal properties of prepared nanocomposites as well as the future challenges are extensively discussed. The present article determines the current status of nanotechnology in the polymer recycling which guide the future studies in this attractive field. Copyright © 2012 Elsevier Ltd. All rights reserved.

Measuring the proton selectivity of graphene membranes

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

Walker, Michael I.; Keyser, Ulrich F., E-mail: ufk20@cam.ac.uk; Braeuninger-Weimer, Philipp

2015-11-23

By systematically studying the proton selectivity of free-standing graphene membranes in aqueous solutions, we demonstrate that protons are transported by passing through defects. We study the current-voltage characteristics of single-layer graphene grown by chemical vapour deposition (CVD) when a concentration gradient of HCl exists across it. Our measurements can unambiguously determine that H{sup +} ions are responsible for the selective part of the ionic current. By comparing the observed reversal potentials with positive and negative controls, we demonstrate that the as-grown graphene is only weakly selective for protons. We use atomic layer deposition to block most of the defects inmore » our CVD graphene. Our results show that a reduction in defect size decreases the ionic current but increases proton selectivity.« less

Encouragement of Early Academic Skills at Home during Early Childhood Period: Validity and Reliability Study of the EASYC Scale

ERIC Educational Resources Information Center

Kara, H. Gözde Ertürk; Çoksoyluer, Seyda Kiliç

2017-01-01

The current study aims to perform the adaptation of the Encouragement of Academic Skills of Young Children (EASYC) Scale into Turkish. The study group was determined by means of the convenience sampling technique. A total of 124 students aged at 48-84 months were included in the sampling of the study. The data collection tools of the study are the…

Evaluation and reporting of enzyme immunoassay determinations of antibody to herpes simplex virus in sera and cerebrospinal fluid.

PubMed Central

Cremer, N E; Cossen, C K; Hanson, C V; Shell, G R

1982-01-01

Several methods for evaluating and reporting enzyme immunoassay (EIA) determinations of antibody to herpes simplex virus derived from one dilution of single serum samples were studied. An EIA ratio method for serological evidence of current infection from paired serum samples was also evaluated. Optical density (OD) of the reaction at a 1:100 serum dilution and estimated titers obtained by reference of the OD of the serum dilution to a standard curve were compared to the corresponding plotted EIA titer obtained by titration to endpoint. Neither the OD per se nor the estimated titer was completely predictive of the plotted titer (correlation coefficient [r] of 0.824 and 0.817, respectively), and they provided only a semiquantitative measurement of antibody concentration. For an antibody status report, however, OD would be sufficient if related to the cutoff value as an EIA index (OD of sample divided by cutoff OD for positive specimens). The OD of the EIA reaction at a single dilution (1:5) of cerebrospinal fluid, on the other hand, correlated quite well with the titer obtained by titration (r = 0.950). For serological diagnosis of current infection, the OD ratio of convalescence-phase/acute-phase sera was determined at several dilutions. A ratio of greater than or equal to 1.54 was calculated as a reliable index for a significant rise in antibody concentration and compatible with current infection. By determining the convalescent-phase/acute-phase serum ratio at two dilutions, 1:100 and 1:1,000, the EIA ratio method appeared to be a sensitive as or more sensitive than, complement fixation in diagnosing current infection. PMID:6284791

Determining Remaining Useful Life of Aging Cables in Nuclear Power Plants – Interim Study FY13

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

Simmons, Kevin L.; Fifield, Leonard S.; Westman, Matthew P.

2013-09-27

The most important criterion for cable performance is its ability to withstand a design-basis accident. With nearly 1000 km of power, control, instrumentation, and other cables typically found in an NPP, it would be a significant undertaking to inspect all of the cables. Degradation of the cable jacket, electrical insulation, and other cable components is a key issue that is likely to affect the ability of the currently installed cables to operate safely and reliably for another 20 to 40 years beyond the initial operating life. The development of one or more nondestructive evaluation (NDE) techniques and supporting models thatmore » could assist in determining the remaining life expectancy of cables or their current degradation state would be of significant interest. The ability to nondestructively determine material and electrical properties of cable jackets and insulation without disturbing the cables or connections has been deemed essential. Currently, the only technique accepted by industry to measure cable elasticity (the gold standard for determining cable insulation degradation) is the indentation measurement. All other NDE techniques are used to find flaws in the cable and do not provide information to determine the current health or life expectancy. There is no single NDE technique that can satisfy all of the requirements needed for making a life-expectancy determination, but a wide range of methods have been evaluated for use in NPPs as part of a continuous evaluation program. The commonly used methods are indentation and visual inspection, but these are only suitable for easily accessible cables. Several NDE methodologies using electrical techniques are in use today for flaw detection but there are none that can predict the life of a cable. There are, however, several physical and chemical ptoperty changes in cable insulation as a result of thermal and radiation damage. In principle, these properties may be targets for advanced NDE methods to provide early warning of aging and degradation. Examples of such key indicators include changes in chemical structure, mechanical modulus, and dielectric permittivity. While some of these indicators are the basis of currently used technologies, there is a need to increase the volume of cable that may be inspected with a single measurement, and if possible, to develop techniques for in-situ inspection (i.e., while the cable is in operation). This is the focus of the present report.« less

Tidal currents and anticyclonic motions on two North Pacific seamounts

USGS Publications Warehouse

Genin, A.; Noble, M.; Lonsdale, P.F.

1989-01-01

Near-bottom currents were measured for several days at three sites on the summits of Fieberling Guyot (32??26???N, 127??46???W) and Horizon Guyot (19??15???N, 160??00???W). Three moorings comprised of two current meters were deployed on each summit; two moorings were deployed on opposite sides of the rim of the summit and one mooring was deployed near the center of the summit. The observed currents were strong, with maximum speeds of 48 and 24 cm s-1 on Fieberling and Horizon, respectively. The currents at specific frequencies were enhanced relative to those in the surrounding ocean. Diurnal currents were the dominant component of the current field on Fieberling Guyot. They accounted for 39-68% of the energy and had amplitudes around 12 cm s-1. We suspect that these diurnal currents were waves trapped over the seamount. Semidiurnal internal tidal currents were the strongest currents over Horizon Guyot, with amplitudes around 4 cm s-1. The flow patterns determined in this study seemed to affect the biological and geological characteristics of the seamounts. ?? 1990.

Synthesis/literature review for determining structural layer coefficients (SLC) of bases.

DOT National Transportation Integrated Search

2014-12-01

FDOTs current method of determining a base material structural layer coefficient (SLC) is detailed in the : Materials Manual, Chapter 2.1, Structural Layer Coefficients for Flexible Pavement Base Materials. : Currently, any new base material not a...

Diagnostic sensitivity of ultrasound, radiography and computed tomography for gender determination in four species of lizards.

PubMed

Di Ianni, Francesco; Volta, Antonella; Pelizzone, Igor; Manfredi, Sabrina; Gnudi, Giacomo; Parmigiani, Enrico

2015-01-01

Gender determination is frequently requested by reptile breeders, especially for species with poor or absent sexual dimorphism. The aims of the current study were to describe techniques and diagnostic sensitivities of ultrasound, radiography, and computed tomography for gender determination (identification of hemipenes) in four species of lizards. Nineteen lizards of known sex, belonging to four different species (Pogona vitticeps, Uromastyx aegyptia, Tiliqua scincoides, Gerrhosaurus major) were prospectively enrolled. With informed owner consent, ultrasound, noncontrast CT, contrast radiography, and contrast CT (with contrast medium administered into the cloaca) were performed in conscious animals. Imaging studies were reviewed by three different operators, each unaware of the gender of the animals and of the results of the other techniques. The lizard was classified as a male when hemipenes were identified. Nineteen lizards were included in the study, 10 females and nine males. The hemipenes were seen on ultrasound in only two male lizards, and appeared as oval hypoechoic structures. Radiographically, hemipenes filled with contrast medium appeared as spindle-shaped opacities. Noncontrast CT identified hemipenes in only two lizards, and these appeared as spindle-shaped kinked structures with hyperattenuating content consistent with smegma. Hemipenes were correctly identified in all nine males using contrast CT (accuracy of 100%). Accuracy of contrast radiography was excellent (94.7%). Accuracy of ultrasound and of noncontrast CT was poor (64.3% and 63.1%, respectively). Findings from the current study supported the use of contrast CT or contrast radiography for gender determination in lizards. © 2014 American College of Veterinary Radiology.

A two-question method for assessing gender categories in the social and medical sciences.

PubMed

Tate, Charlotte Chuck; Ledbetter, Jay N; Youssef, Cris P

2013-01-01

Three studies (N = 990) assessed the statistical reliability of two methods of determining gender identity that can capture transgender spectrum identities (i.e., current gender identities different from birth-assigned gender categories). Study 1 evaluated a single question with four response options (female, male, transgender, other) on university students. The missing data rate was higher than the valid response rates for transgender and other options using this method. Study 2 evaluated a method of asking two separate questions (i.e., one for current identity and another for birth-assigned category), with response options specific to each. Results showed no missing data and two times the transgender spectrum response rate compared to Study 1. Study 3 showed that the two-question method also worked in community samples, producing near-zero missing data. The two-question method also identified cisgender identities (same birth-assigned and current gender identity), making it a dynamic and desirable measurement tool for the social and medical sciences.

Heat treatment effects in Cu2S-CdS heterojunction photovoltaic cells

NASA Technical Reports Server (NTRS)

Fahrenbruch, A. L.; Bube, R. H.

1974-01-01

The dependence of the short-circuit current on photon energy, temperature, and the state of optical degradation (or enhancement) is determined in a study of the photovoltaic properties of Cu2S-CdS single-crystal heterojunctions. A coherent formulation is proposed for the relationship between enhancement and optical degradation and for their effects on the transport of a short-circuit photoexcited current and dark forward-bias current in a photovoltaic cell. Optical degradation in a Cu2S-CdS cell is shown to be identical to the optical degradation of lifetime in a homogeneous CdS:Cd:Cu crystal.

Assessment of government tribology programs

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

Peterson, M.B.; Levinson, T.M.

1985-09-01

An assessment has been made to determine current tribology research and development work sponsored or conducted by the government. Data base surveys and discussions were conducted to isolate current projects sponsored primarily by 21 different government organizations. These projects were classified by subject, objective, energy relevance, type of research, phenomenon being investigated, variables being studied, type of motion, materials and application. An abstract of each project was prepared which included the classification, sponsor, performing organization and a project description. It was found that current work is primarily materials oriented to meet military requirements. Other than the high temperature programs verymore » few of the tribology projects accomplish energy related objectives.« less

Theoretical and experimental studies of error in square-law detector circuits

NASA Technical Reports Server (NTRS)

Stanley, W. D.; Hearn, C. P.; Williams, J. B.

1984-01-01

Square law detector circuits to determine errors from the ideal input/output characteristic function were investigated. The nonlinear circuit response is analyzed by a power series expansion containing terms through the fourth degree, from which the significant deviation from square law can be predicted. Both fixed bias current and flexible bias current configurations are considered. The latter case corresponds with the situation where the mean current can change with the application of a signal. Experimental investigations of the circuit arrangements are described. Agreement between the analytical models and the experimental results are established. Factors which contribute to differences under certain conditions are outlined.

Nano-electron beam induced current and hole charge dynamics through uncapped Ge nanocrystals

NASA Astrophysics Data System (ADS)

Marchand, A.; El Hdiy, A.; Troyon, M.; Amiard, G.; Ronda, A.; Berbezier, I.

2012-04-01

Dynamics of hole storage in spherical Ge nanocrystals (NCs) formed by a two step dewetting/nucleation process on an oxide layer grown on an n-doped <001> silicon substrate is studied using a nano-electron beam induced current technique. Carrier generation is produced by an electron beam irradiation. The generated current is collected by an atomic force microscope—tip in contact mode at a fixed position away from the beam spot of about 0.5 µm. This distance represents the effective diffusion length of holes. The time constants of holes charging are determined and the effect of the NC size is underlined.

EVALUATION OF PERFLUOROOCTANE SULFONATE IN THE RAT BRAIN

EPA Science Inventory

Perfluorooctane Sulfonate (PFOS) is an environmentally persistent chemical that has been detected in humans and wildlife. PFOS is primarily distributed in liver and blood. The current study evaluated the level of PFOS in the adult and neonatal rat brain and determined whether t...

Registration Priorities: A Report.

ERIC Educational Resources Information Center

Walters, Judy E.

In May 1993, the California Community Colleges' Board of Governors adopted systemwide guidelines recommending student registration priorities to help address current discrepancies between available resources and courses and the colleges' open-door mission. This report describes the guidelines and results of a study conducted to determine their…

Use of edge line markings on rural two-lane highways.

DOT National Transportation Integrated Search

2008-01-01

The objective of this study was to review roadway characteristics and crash data in Kentucky and determine if revisions should be made to current guidelines for the sue of edge lines. Recommendations were made concerning the use of edge lines, center...

Development and proposed implementation of a field permeability test for a asphalt concrete.

DOT National Transportation Integrated Search

2001-07-01

The objectives of this study were as follows: : 1) To review research performed by others and determine the state-of-the-art of field permeability measurements; : 2) To review current laboratory permeability testing devices and their testing procedur...

Comparing airport licensing requirements : Alabama vs. selected states and the FAA

DOT National Transportation Integrated Search

2001-12-01

Many states in the United States of America have licensing requirements for their general use airports. The objective of this study was to determine if current Alabama's regulations for general use airports are timely and if they compare favorably wi...

RECREATIONAL WATER QUALITY AND SWIMMING ASSOCIATED HEALTH EFFECTS

EPA Science Inventory

The U.S. EPA's National Epidemiological and Environmental Assessment of Recreational Water study is currently underway with the goal of determining if new rapid methods for measuring water quality can be used to predict illness in swimmers. This lecture will provide a historical...

Timely precipitation drives cover crop outcomes

USDA-ARS?s Scientific Manuscript database

Cover crops can expand ecosystem services, though sound management recommendations for their use within semi-arid cropping systems is currently constrained by a lack of information. This study was conducted to determine agroecosystem responses to late-summer seeded cover crops under no-till managem...

Expedient Approaches for the Management of Wastes ...

EPA Pesticide Factsheets

Report The current study sought to determine waste decontamination conditions that would achieve complete kill for all material types. For these tests, more stringent decontamination procedures were evaluated specifically using pAB amended with a surfactant and/or waste submersion procedures involving agitation.

Conditional data watchpoint management

DOEpatents

Burdick, Dean Joseph; Vaidyanathan, Basu

2010-08-24

A method, system and computer program product for managing a conditional data watchpoint in a set of instructions being traced is shown in accordance with illustrative embodiments. In one particular embodiment, the method comprises initializing a conditional data watchpoint and determining the watchpoint has been encountered. Upon that determination, examining a current instruction context associated with the encountered watchpoint prior to completion of the current instruction execution, further determining a first action responsive to a positive context examination; otherwise, determining a second action.

Comparison between current and ideal condition of educational justice from the students' viewpoints at Jahrom Nursing and Paramedical School.

PubMed

Montaseri, Mohammad Ali; Hojat, Mohsen; Karimyar Jahromi, Mahdi

2014-01-01

Educational justice is a process by which all those involved in education are pondering and seeking to establish it in their regulatory environments. This study aimed to investigate effective factors in an ideal educational justice and the current condition of educational justice from the students' viewpoint and ultimately increase the awareness and understanding of authorities and educational planners of the existing shortcomings.  This is a descriptive-analytical study. Samples include all nursing, operating room, and anesthesia students of nursing and paramedical college who had passed at least 5 semesters. Data collection was carried out through a scholar questionnaire. Validity was assessed through content validity and reliability of the questionnaire was evaluated using a pilot study.  In order to determine the status of the scores, 5 points (very high), 4 (often), 3 (moderate), 2 (low) and 1 (very low) were assigned, respectively. To determine the justice level, a 35 score interval was considered as very low, low, medium, high and very high. SPSS software, descriptive statistics, independent t-test and ANOVA were used to analyze the data.  There was a significant difference between the ideal and the current conditions in all items (p≤0.001) and also in the total mean score of ideal condition  and mean score of current condition (p=0.010). In an educational system, educational methods and aims should be regulated in a way that principles and components of justice are attainable and distribution and allocation of educational facilities of justice are considered thoroughly.

Comparison between current and ideal condition of educational justice from the students’ viewpoints at Jahrom Nursing and Paramedical School

PubMed Central

MONTASERI, MOHAMMAD ALI; HOJAT, MOHSEN; KARIMYAR JAHROMI, MAHDI

2014-01-01

Introduction: Educational justice is a process by which all those involved in education are pondering and seeking to establish it in their regulatory environments. This study aimed to investigate effective factors in an ideal educational justice and the current condition of educational justice from the students’ viewpoint and ultimately increase the awareness and understanding of authorities and educational planners of the existing shortcomings.  Methods: This is a descriptive-analytical study. Samples include all nursing, operating room, and anesthesia students of nursing and paramedical college who had passed at least 5 semesters. Data collection was carried out through a scholar questionnaire. Validity was assessed through content validity and reliability of the questionnaire was evaluated using a pilot study.  In order to determine the status of the scores, 5 points (very high), 4 (often), 3 (moderate), 2 (low) and 1 (very low) were assigned, respectively. To determine the justice level, a 35 score interval was considered as very low, low, medium, high and very high. SPSS software, descriptive statistics, independent t-test and ANOVA were used to analyze the data.  Results: There was a significant difference between the ideal and the current conditions in all items (p≤0.001) and also in the total mean score of ideal condition  and mean score of current condition (p=0.010). Conclusion: In an educational system, educational methods and aims should be regulated in a way that principles and components of justice are attainable and distribution and allocation of educational facilities of justice are considered thoroughly. PMID:25512917

The strange sea density and charm production in deep inelastic charged current processes

NASA Astrophysics Data System (ADS)

Glück, M.; Kretzer, S.; Reya, E.

1996-02-01

Charm production as related to the determination of the strange sea density in deep inelastic charged current processes is studied predominantly in the framework of the overlineMS fixed flavor factorization scheme. Perturbative stability within this formalism is demonstrated. The compatibility of recent next-to-leading order strange quark distributions with the available dimuon and F2νN data is investigated. It is shown that final conclusions concerning these distributions afford further analyses of presently available and/or forthcoming neutrino data.

Laboratory Demonstration of Abiotic Technologies for Removal of RDX from a Process Waste Stream

DTIC Science & Technology

2010-06-01

Americas , Inc. San Diego, CA). Previous batch studies had determined the need for periodic current switching to keep the cathode clear of deposited...summarized in Table 24. Current was supplied to the reactor cell through the constructed leads by a 30V– 300A power supply (TDK Lambda Americas , Inc. San...C., D. A. Kubose, and D. J. Glover . 1977. Kinetic isotope effects and inter- mediate formation for the aqueous alkaline homogenous hydrolysis of 1,3,5

Observation of reflected waves on the SABRE positive polarity inductive adder MITL

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

Cuneo, M.E.; Poukey, J.W.; Mendel, C.W.

We are studying the coupling of extraction applied-B ion diodes to Magnetically Insulated Transmission Line (MITLs) on the SABRE (Sandia Accelerator and Beam Research Experiment, 6 MV, 300 kA) positive polarity inductive voltage adder. Our goal is to determine conditions under which efficient coupling occurs. The best total power efficiency for an ideal ion diode load (i.e., without parasitic losses) is obtained by maximizing the product of cathode current and gap voltage. MITLs require that the load impedance be undermatched to the self-limited line operating impedance for efficient transfer of power to ion diodes, independent of transit time isolation, andmore » even in the case of multiple cathode system with significant vacuum electron flow. We observe that this undermatched condition results in a reflected wave which decreases the line voltage and gap electron sheath current, and increases the anode and cathode current in a time-dependent way. The MITL diode coupling is determined by the flow impedance at the adder exit. We also show that the flow impedance increases along the extension MITL on SABRE. Experimental measurements of current and peak voltage are compared to analytical models and TWOQUICK 2.5-D PIC code simulations.« less

Design of conduction cooling system for a high current HTS DC reactor

NASA Astrophysics Data System (ADS)

Dao, Van Quan; Kim, Taekue; Le Tat, Thang; Sung, Haejin; Choi, Jongho; Kim, Kwangmin; Hwang, Chul-Sang; Park, Minwon; Yu, In-Keun

2017-07-01

A DC reactor using a high temperature superconducting (HTS) magnet reduces the reactor’s size, weight, flux leakage, and electrical losses. An HTS magnet needs cryogenic cooling to achieve and maintain its superconducting state. There are two methods for doing this: one is pool boiling and the other is conduction cooling. The conduction cooling method is more effective than the pool boiling method in terms of smaller size and lighter weight. This paper discusses a design of conduction cooling system for a high current, high temperature superconducting DC reactor. Dimensions of the conduction cooling system parts including HTS magnets, bobbin structures, current leads, support bars, and thermal exchangers were calculated and drawn using a 3D CAD program. A finite element method model was built for determining the optimal design parameters and analyzing the thermo-mechanical characteristics. The operating current and inductance of the reactor magnet were 1,500 A, 400 mH, respectively. The thermal load of the HTS DC reactor was analyzed for determining the cooling capacity of the cryo-cooler. The study results can be effectively utilized for the design and fabrication of a commercial HTS DC reactor.

Determination of crack depth in aluminum using eddy currents and GMR sensors

NASA Astrophysics Data System (ADS)

Lopes Ribeiro, A.; Pasadas, D.; Ramos, H. G.; Rocha, T.

2015-03-01

In this paper we use eddy currents to determine the depth of linear cracks in aluminum plates. A constant field probe is used to generate the spatially uniform excitation field and a single axis giant magneto-resistor (GMR) sensor is used to measure the eddy currents magnetic field. Different depths were machined in one aluminum plate with 4 mm of thickness. By scanning those cracks the magnetic field components parallel and perpendicular to the crack's line were measured when the eddy currents were launched perpendicularly to the crack's line. To characterize one crack in a plate of a given thickness and material, the experimental procedure was defined. The plate surface is scanned to detect and locate one crack. The acquired data enables the determination of the crack's length and orientation. A second scanning is performed with the excitation current perpendicular to the crack and the GMR sensing axis perpendicular and parallel to the crack's line.

Electronic thermometry in tunable tunnel junction

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

Maksymovych, Petro

A tunable tunnel junction thermometry circuit includes a variable width tunnel junction between a test object and a probe. The junction width is varied and a change in thermovoltage across the junction with respect to the change in distance across the junction is determined. Also, a change in biased current with respect to a change in distance across the junction is determined. A temperature gradient across the junction is determined based on a mathematical relationship between the temperature gradient, the change in thermovoltage with respect to distance and the change in biased current with respect to distance. Thermovoltage may bemore » measured by nullifying a thermoelectric tunneling current with an applied voltage supply level. A piezoelectric actuator may modulate the probe, and thus the junction width, to vary thermovoltage and biased current across the junction. Lock-in amplifiers measure the derivatives of the thermovoltage and biased current modulated by varying junction width.« less

Cathodic Potential Dependence of Electrochemical Reduction of SiO2 Granules in Molten CaCl2

NASA Astrophysics Data System (ADS)

Yang, Xiao; Yasuda, Kouji; Nohira, Toshiyuki; Hagiwara, Rika; Homma, Takayuki

2016-09-01

As part of an ongoing fundamental study to develop a new process for producing solar-grade silicon, this paper examines the effects of cathodic potential on reduction kinetics, current efficiency, morphology, and purity of Si product during electrolysis of SiO2 granules in molten CaCl2 at 1123 K (850 °C). SiO2 granules were electrolyzed potentiostatically at different cathodic potentials (0.6, 0.8, 1.0, and 1.2 V vs Ca2+/Ca). The reduction kinetics was evaluated based on the growth of the reduced Si layer and the current behavior during electrolysis. The results suggest that a more negative cathodic potential is favorable for faster reduction. Current efficiencies in 60 minutes are greater than 65 pct at all the potentials examined. Si wires with sub-micron diameters are formed, and their morphologies show little dependence on the cathodic potential. The impurities in the Si product can be controlled at low level. The rate-determining step for the electrochemical reduction of SiO2 granules in molten CaCl2 changes with time. At the initial stage of electrolysis, the electron transfer is the rate-determining step. At the later stage, the diffusion of O2- ions is the rate-determining step. The major cause of the decrease in reduction rate with increasing electrolysis time is the potential drop from the current collector to the reaction front due to the increased contact resistance among the reduced Si particles.

Analyzing the dependence of oxygen incorporation current density on overpotential and oxygen partial pressure in mixed conducting oxide electrodes.

PubMed

Guan, Zixuan; Chen, Di; Chueh, William C

2017-08-30

The oxygen incorporation reaction, which involves the transformation of an oxygen gas molecule to two lattice oxygen ions in a mixed ionic and electronic conducting solid, is a ubiquitous and fundamental reaction in solid-state electrochemistry. To understand the reaction pathway and to identify the rate-determining step, near-equilibrium measurements have been employed to quantify the exchange coefficients as a function of oxygen partial pressure and temperature. However, because the exchange coefficient contains contributions from both forward and reverse reaction rate constants and depends on both oxygen partial pressure and oxygen fugacity in the solid, unique and definitive mechanistic assessment has been challenging. In this work, we derive a current density equation as a function of both oxygen partial pressure and overpotential, and consider both near and far from equilibrium limits. Rather than considering specific reaction pathways, we generalize the multi-step oxygen incorporation reaction into the rate-determining step, preceding and following quasi-equilibrium steps, and consider the number of oxygen ions and electrons involved in each. By evaluating the dependence of current density on oxygen partial pressure and overpotential separately, one obtains the reaction orders for oxygen gas molecules and for solid-state species in the electrode. We simulated the oxygen incorporation current density-overpotential curves for praseodymium-doped ceria for various candidate rate-determining steps. This work highlights a promising method for studying the exchange kinetics far away from equilibrium.

Measurements of the reverse current of highly irradiated silicon sensors to determine the effective energy and current related damage rate

NASA Astrophysics Data System (ADS)

Wiehe, Moritz; Wonsak, S.; Kuehn, S.; Parzefall, U.; Casse, G.

2018-01-01

The reverse current of irradiated silicon sensors leads to self heating of the sensor and degrades the signal to noise ratio of a detector. Precise knowledge of the expected reverse current during detector operation is crucial for planning and running experiments in High Energy Physics. The dependence of the reverse current on sensor temperature and irradiation fluence is parametrized by the effective energy and the current related damage rate, respectively. In this study 18 n-in-p mini silicon strip sensors from companies Hamamatsu Photonics and Micron Semiconductor Ltd. were deployed. Measurements of the reverse current for different bias voltages were performed at temperatures of -32 ° C, -27 ° C and -23 ° C. The sensors were irradiated with reactor neutrons in Ljubljana to fluences ranging from 2 × 1014neq /cm2 to 2 × 1016neq /cm2. The measurements were performed directly after irradiation and after 10 and 30 days of room temperature annealing. The aim of the study presented in this paper is to investigate the reverse current of silicon sensors for high fluences of up to 2 × 1016neq /cm2 and compare the measurements to the parametrization models.

The association between smoking and blood pressure in men: a cross-sectional study.

PubMed

Li, Guoju; Wang, Hailing; Wang, Ke; Wang, Wenrui; Dong, Fen; Qian, Yonggang; Gong, Haiying; Hui, Chunxia; Xu, Guodong; Li, Yanlong; Pan, Li; Zhang, Biao; Shan, Guangliang

2017-10-10

Cigarette smoking is a known risk factor for cardiovascular disease (CVD), but the association between smoking and blood pressure is unclear. Thus, the current study examined the association between cigarette smoking and blood pressure in men. Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and pulse pressure (PP) were examined using digital blood pressure measuring device, and smoking status was determined with China National Health Survey. The ANCOVA showed that the adjusted DBP and MAP were lower in current smokers versus nonsmokers and the adjusted SBP was lower in current smokers versus former smokers (P < 0.05). Additionally, the adjusted PP tend to be decreased steadily as the pack·years increased in current smokers. In a fully adjusted logistic regression model, former smokers had increased ORs (95% CI) of 1.48 (1.01, 2.18) of hypertension and current smokers had not increased ORs (95% CI) of 0.83 (0.61, 1.12), compared with never smokers. The findings revealed that the adjusted blood pressure were lower in current smokers versus nonsmokers and former smokers. No significant dose-dependent effect of current smoking on blood pressure indices except PP was observed. Smoking cessation was significantly associated with an increased risk of hypertension. However, current smoking was not a risk factor of hypertension.

75 FR 39701 - Revision of a Currently Approved Collection: Users, Uses, and Benefits of Landsat Satellite Imagery

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-12

.... Abstract In 2008, the USGS's Land Remote Sensing (LRS) Program initiated a study to determine the users, uses, and benefits of Landsat imagery. Before that study, there had been very limited assessments of...: Users, Uses, and Benefits of Landsat Satellite Imagery AGENCY: United States Geological Survey (USGS...

Five-Year-Olds Can Show the Self-Reference Advantage

ERIC Educational Resources Information Center

Sui, Jie; Zhu, Ying

2005-01-01

The current study developed a new paradigm to determine the age at which children begin to show the self-reference advantage in memory. Four-, 5-, and 10-year-olds studied lists of colourful object pictures presented together with self or other face image, and participants were asked to report aloud "who is pointing at the (object)."…

The Relationship between the Pre-Service Classroom Teachers' Techno Pedagogical Instructional Competencies and Epistemological Beliefs

ERIC Educational Resources Information Center

Yorulmaz, Alper; Can, Süleyman; Çokçaliskan, Halil

2017-01-01

The purpose of the current study is to determine the relationship between the pre-service classroom teachers' epistemological beliefs and techno pedagogical subject-area competencies. While the universe of the study is comprised of a total of 187 senior pre-service teachers attending the Department of Classroom Teacher Education in Mugla Sitki…

Modeling the Factors Associated with Children's Mental Health Difficulties in Primary School: A Multilevel Study

ERIC Educational Resources Information Center

Humphrey, Neil; Wigelsworth, Michael

2012-01-01

The current study explores some of the factors associated with children's mental health difficulties in primary school. Multilevel modeling with data from 628 children from 36 schools was used to determine how much variation in mental health difficulties exists between and within schools, and to identify characteristics at the school and…

Affective Structures among Students and Its Relationship with Academic Burnout with Emphasis on Gender

ERIC Educational Resources Information Center

Bikar, Somaye; Marziyeh, Afsaneh; Pourghaz, Abdolwahab

2018-01-01

This study aimed to determine the relationship between affective structures and academic burnout among male and female third-grade high school students in Zahedan in the academic year 2016-2017. The current descriptive-correlational study had a sample including 362 students selected using a multistage cluster sampling method. To collect data,…

A Comparative Study of the Determinants of Future Plans and Expectations of Business Students

ERIC Educational Resources Information Center

Black, Gregory S.; Schofield, April L.

2018-01-01

Current university juniors and seniors have plans and expectations for after they graduate. In an effort to better understand these plans and expectations, the authors assessed a sample of 334 university students enrolled in business classes. The study examined the impact of three categories of independent variables--family influences, demographic…

The Relationship between Leisure Constraints, Constraint Negotiation Strategies and Facilitators with Recreational Sport Activity Participation of College Students

ERIC Educational Resources Information Center

Kocak, Funda

2017-01-01

The aim of this study is to determine the constraints in participating the leisure activities for college students, the strategies of negotiation regarding these constraints and the relationship between the facilitators and activity participation. The population of the study consists of currently registered students from Ankara University.…

The Relationship among Stress, Burnout, and Locus of Control of School Psychologists

ERIC Educational Resources Information Center

Reece, Shana J.

2010-01-01

The purpose of this study was to determine how stress, burnout, and locus of control are related for school psychologists providing direct services in the Metropolitan Nashville Public School System. This knowledge is essential in providing the needed experience and outlook of working as a school psychologist. The current study provided school…