Sample records for current study presents

  1. Best Practices for Evaluating the Capability of Nondestructive Evaluation (NDE) and Structural Health Monitoring (SHM) Techniques for Damage Characterization (Post-Print)

    DTIC Science & Technology

    2016-02-10

    a wide range of part, environmental and damage conditions. Best practices of using models are presented for both an eddy current NDE sizing and...to assess the reliability of NDE and SHM characterization capability. Best practices of using models are presented for both an eddy current NDE... EDDY CURRENT NDE CASE STUDY An eddy current crack sizing case study is presented to highlight examples of some of these complex characteristics of

  2. 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.

  3. Nondestructive Testing Eddy Current Basic Principles RQA/M1-5330.12 (V-I).

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Huntsville, AL. George C. Marshall Space Flight Center.

    As one in the series of programmed instruction handbooks, prepared by the U.S. space program, home study material is presented in this volume concerning familiarization and orientation on basic eddy current principles. The subject is presented under the following headings: Basic Eddy Current Concepts, Eddy Current Generation and Distribution,…

  4. Current status of water environment and their microbial biosensor techniques - Part II: Recent trends in microbial biosensor development.

    PubMed

    Nakamura, Hideaki

    2018-05-08

    In Part I of the present review series, I presented the current state of the water environment by focusing on Japanese cases and discussed the need to further develop microbial biosensor technologies for the actual water environment. I comprehensively present trends after approximately 2010 in microbial biosensor development for the water environment. In the first section, after briefly summarizing historical studies, recent studies on microbial biosensor principles are introduced. In the second section, recent application studies for the water environment are also introduced. Finally, I conclude the present review series by describing the need to further develop microbial biosensor technologies. Graphical abstract Current water pollution indirectly occurs by anthropogenic eutrophication (Part I). Recent trends in microbial biosensor development for water environment are described in part II of the present review series.

  5. Evaluation of constant current alternating current iontophoresis for transdermal drug delivery.

    PubMed

    Yan, Guang; Li, S Kevin; Higuchi, William I

    2005-12-10

    Previous studies in our laboratory have demonstrated that alternating current (AC) iontophoresis can significantly decrease skin electric resistance and enhance the transport of charged permeants across skin. Flux variability of neutral permeants during AC iontophoresis was also found to be less than that of conventional direct current (DC) iontophoresis. The objectives of the present study were to evaluate flux enhancement of constant current AC transdermal iontophoresis and compare the AC flux with that of constant current DC iontophoresis. Iontophoresis studies of AC amplitude of 1, 2, and 5 mA were conducted in side-by-side diffusion cells with donor solution of 0.015, 0.15, and 1.0 M tetraethylammonium (TEA) chloride and receiver solution of phosphate buffered saline (PBS) using human epidermal membrane (HEM). Conventional constant current DC iontophoresis of 0.2 mA was also performed under similar conditions. TEA and mannitol were the model permeants. The following are the major findings in the present study. The flux of TEA increased proportionally with the AC current for all three TEA chloride concentrations and at the AC frequency used in the present study. When the permeant and its counter ion were the only ionic species in the donor chamber, the fluxes during DC iontophoresis were weakly dependent of its donor concentration. The fluxes of TEA during constant current AC iontophoresis were moderately related to the donor concentration with the highest TEA flux observed under the 1.0 M TEA chloride condition although the relationship between flux and donor concentration was not linear. A trend of decreasing electroosmotic transport with increasing donor TEA chloride concentration was observed with significant sample-to-sample variability during DC iontophoresis. Mannitol permeability was also observed to decrease with increasing TEA chloride concentration in the donor under the AC conditions, but data variability under AC was significantly smaller than that under DC. The results in the present study indicate that constant current AC iontophoresis under conditions tolerable to human (2 and 5 mA) can provide predictable fluxes that were lower than but of comparable magnitude as those of conventional constant current DC iontophoresis (0.2 mA).

  6. 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.

  7. The Exploring Nature of Definitions and Classifications of Language Learning Strategies (LLSs) in the Current Studies of Second/Foreign Language Learning

    ERIC Educational Resources Information Center

    Fazeli, Seyed Hossein

    2011-01-01

    This study aims to explore the nature of definitions and classifications of Language Learning Strategies (LLSs) in the current studies of second/foreign language learning in order to show the current problems regarding such definitions and classifications. The present study shows that there is not a universal agreeable definition and…

  8. Possibilities and limitations of current stereo-endoscopy.

    PubMed

    Mueller-Richter, U D A; Limberger, A; Weber, P; Ruprecht, K W; Spitzer, W; Schilling, M

    2004-06-01

    Stereo-endoscopy has become a commonly used technology. In many comparative studies striking advantages of stereo-endoscopy over two-dimensional presentation could not be proven. To show the potential and fields for further improvement of this technology is the aim of this article. The physiological basis of three-dimensional vision limitations of current stereo-endoscopes is discussed and fields for further research are indicated. New developments in spatial picture acquisition and spatial picture presentation are discussed. Current limitations of stereo-endoscopy that prevent a better ranking in comparative studies with two-dimensional presentation are mainly based on insufficient picture acquisition. Devices for three-dimensional picture presentation are at a more advanced developmental stage than devices for three-dimensional picture acquisition. Further research should emphasize the development of new devices for three-dimensional picture acquisition.

  9. 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.

  10. A new theoretical model for transmembrane potential and ion currents induced in a spherical cell under low frequency electromagnetic field.

    PubMed

    Zheng, Yu; Gao, Yang; Chen, Ruijuan; Wang, Huiquan; Dong, Lei; Dou, Junrong

    2016-10-01

    Time-varying electromagnetic fields (EMF) can induce some physiological effects in neuronal tissues, which have been explored in many applications such as transcranial magnetic stimulation. Although transmembrane potentials and induced currents have already been the subjects of many theoretical studies, most previous works about this topic are mainly completed by utilizing Maxwell's equations, often by solving a Laplace equation. In previous studies, cells were often considered to be three-compartment models with different electroconductivities in different regions (three compartments are often intracellular regions, membrane, and extracellular regions). However, models like that did not take dynamic ion channels into consideration. Therefore, one cannot obtain concrete ionic current changes such as potassium current change or sodium current change by these models. The aim of the present work is to present a new and more detailed model for calculating transmembrane potentials and ionic currents induced by time-varying EMF. Equations used in the present paper originate from Nernst-Plank equations, which are ionic current-related equations. The main work is to calculate ionic current changes induced by EMF exposure, and then transmembrane potential changes are calculated with Hodgkin-Huxley model. Bioelectromagnetics. 37:481-492, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  11. Health, United States, 1979.

    ERIC Educational Resources Information Center

    National Center for Health Statistics (DHEW/PHS), Hyattsville, MD.

    This study presents statistics concerning recent trends in the health care sector and detailed discussions of selected current health issues. The first part of this report consists of four chapters, each covering a current issue. Chapter one presents recent data on the health characteristics of minority groups in the U.S. Chapter two discusses the…

  12. Detecting Breech Presentation Before Labour: Lessons From a Low-Risk Maternity Clinic.

    PubMed

    Ressl, Bill; O'Beirne, Maeve

    2015-08-01

    Evaluation of fetal position is an important part of prenatal care. A woman with a breech presentation may need referral for external cephalic version, for assisted breech delivery, or to schedule a Caesarean section. In many centres, a breech presentation undetected until labour will result in an emergency Caesarean section, a less desirable alternative for both the mother and the health care system. The anecdotal reports of undiagnosed breech presentations at a busy maternity clinic prompted a study to quantify the missed breech presentations and to evaluate the effectiveness of the current detection process, with the aim of allowing no more than 1% of breech presentations to remain undetected until labour. We performed a retrospective analysis of 102 breech deliveries over a 14 month period to quantify missed breech presentations, and used a prospective physician survey documenting how fetal presentation was determined at 186 prenatal visits over four months to analyze the current detection process. We found that approximately 8% of breech presentations were undetected until labour. We concluded that within the limitations of the small sample size evaluated, the current practice of using a vaginal examination to verify fetal presentation determined by abdominal palpation (Leopold's manoeuvres) may not be more accurate than abdominal palpation alone. The current detection process resulted in an unacceptably high rate of missed breech presentations. The results of this study prompted the clinic's acquisition of bedside ultrasound capability to assess fetal position.

  13. A study of point discharge current observations in the thunderstorm environment at a tropical station during the year 1987 and 1988

    NASA Technical Reports Server (NTRS)

    Manohar, G. K.; Kandalgaonkar, S. S.; Sholapurkar, S. M.

    1991-01-01

    The results of the measurements of point discharge current observations at Pune, India, during years 1987 and 1988 are presented by categorizing and studying their number of spells, polar current average durations, and current magnitudes in day-time and night-time conditions. While the results showed that the thunderstorm activity occupies far more day-time than the night-time the level of current magnitudes remains nearly the same in the two categories.

  14. Electron kinematics in a plasma focus

    NASA Technical Reports Server (NTRS)

    Hohl, F.; Gary, S. P.

    1977-01-01

    The results of numerical integrations of the three-dimensional relativistic equations of motion of electrons subject to given electric and magnetic fields are presented. Fields due to two different models are studied: (1) a circular distribution of current filaments, and (2) a uniform current distribution; both the collapse and the current reduction phases are studied in each model. Decreasing current in the uniform current model yields 100 keV electrons accelerated toward the anode and, as for earlier ion computations, provides general agreement with experimental results.

  15. The role of eye movements in decision making and the prospect of exposure effects.

    PubMed

    Bird, Gary D; Lauwereyns, Johan; Crawford, Matthew T

    2012-05-01

    The aim of the current study was to follow on from previous findings that eye movements can have a causal influence on preference formation. Shimojo et al. (2003) previously found that faces that were presented for a longer duration in a two alternative forced choice task were more likely to be judged as more attractive. This effect only occurred when an eye movement was made towards the faces (with no effect when faces were centrally presented). The current study replicated Shimojo et al.'s (2003) design, whilst controlling for potential inter-stimuli interference in central presentations. As per previous findings, when eye movements were made towards the stimuli, faces that were presented for longer durations were preferred. However, faces that were centrally presented (thus not requiring an eye movement) were also preferred in the current study. The presence of an exposure duration effect for centrally presented faces casts doubt on the necessity of the eye movement in this decision making process and has implications for decision theories that place an emphasis on the role of eye movements in decision making. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Current Research on Adolescence and its Program Implications.

    ERIC Educational Resources Information Center

    Cvetkovich, George; Grote, Barbara

    This paper discusses program implications of research on adolescents. A brief historical review of teenage sexuality is presented in order to put current information in perspective. The present increase in teenage fertility is seen as part of a larger epidemic failure of socialization. A number of recent studies are reviewed and synthesized,…

  17. Kinship Care: Improving Practice through Research.

    ERIC Educational Resources Information Center

    Gleeson, James P., Ed.; Hairston, Creasie Finney, Ed.

    Family members have traditionally provided kinship care for each other in times of crisis. Recently, such care has become part of the child welfare system. This edited volume presents several studies designed to identify current knowledge about kinship care as a child welfare service. Presented in five parts, the book summarizes the current state…

  18. Current distribution in conducting nanowire networks

    NASA Astrophysics Data System (ADS)

    Kumar, Ankush; Vidhyadhiraja, N. S.; Kulkarni, Giridhar U.

    2017-07-01

    Conducting nanowire networks find diverse applications in solar cells, touch-screens, transparent heaters, sensors, and various related transparent conducting electrode (TCE) devices. The performances of these devices depend on effective resistance, transmittance, and local current distribution in these networks. Although, there have been rigorous studies addressing resistance and transmittance in TCE, not much attention is paid on studying the distribution of current. Present work addresses this compelling issue of understanding current distribution in TCE networks using analytical as well as Monte-Carlo approaches. We quantified the current carrying backbone region against isolated and dangling regions as a function of wire density (ranging from percolation threshold to many multiples of threshold) and compared the wired connectivity with those obtained from template-based methods. Further, the current distribution in the obtained backbone is studied using Kirchhoff's law, which reveals that a significant fraction of the backbone (which is believed to be an active current component) may not be active for end-to-end current transport due to the formation of intervening circular loops. The study shows that conducting wire based networks possess hot spots (extremely high current carrying regions) which can be potential sources of failure. The fraction of these hot spots is found to decrease with increase in wire density, while they are completely absent in template based networks. Thus, the present work discusses unexplored issues related to current distribution in conducting networks, which are necessary to choose the optimum network for best TCE applications.

  19. Study of eddy current probes

    NASA Technical Reports Server (NTRS)

    Workman, Gary L.; Wang, Morgan

    1992-01-01

    The recognition of materials properties still presents a number of problems for nondestructive testing in aerospace systems. This project attempts to utilize current capabilities in eddy current instrumentation, artificial intelligence, and robotics in order to provide insight into defining geometrical aspects of flaws in composite materials which are capable of being evaluated using eddy current inspection techniques.

  20. Current devices of respiratory physiotherapy

    PubMed Central

    Hristara-Papadopoulou, A; Tsanakas, J; Diomou, G; Papadopoulou, O

    2008-01-01

    In recent years patients with respiratory diseases use various devices, which help the removal of mucus from the airways and the improvement of pulmonary function. The aim of the present study is to determine the effectiveness of the current devices of respiratory physiotherapy, as it comes from the review of literature. The current devices of physiotherapy for patients with respiratory diseases, are presented as an alternative therapy method or a supplemental therapy and they can motivate patients to apply therapy by themselves. These devices seem to increase patients' compliance to daily treatment, because they present many benefits, as independent application, full control of therapy and easy use. These devices are the Positive Expiratory Pressure, the High Frequency Chest Wall Oscillation, the Oral High Frequency Oscillation, the Intrapulmonary Percussive Ventilation, the Incentive Spirometry the Flutter and the Acapella and the Cornet. Current devices seem to be effective in terms of mucus expectoration and pulmonary function improvement, as it is shown by published studies. The choice of the suitable device for each patient is a challenge for the physiotherapist in order to achieve better compliance in daily treatment. More controlled studies are needed due to the fact that the number of published studies is limited. PMID:19158964

  1. Small transport aircraft technology. [STAT

    NASA Technical Reports Server (NTRS)

    Galloway, T. L.

    1981-01-01

    The results of contracted studies identifying the potential benefits of advanced technology are presented. Current in house studies and research efforts are discussed. An overview of the proposed technology elements in STAT research is presented.

  2. Factors Involved in the Intent to Move from One Team to Another among Handball Players

    ERIC Educational Resources Information Center

    Fruchart, Eric; Mullet, Etienne

    2012-01-01

    The study was about a non normative within-career transition in sport: Handball players' move from their current to an alternative team. Eighty male handball players were presented with scenarios that contained five pieces of information about current satisfaction with the present team, attractiveness of the alternative team (better springboard…

  3. A Synthesis of Language Learning Strategies: Current Issues, Problems and Claims Made in Learner Strategy Research

    ERIC Educational Resources Information Center

    Barjesteh, Hamed; Mukundan, Jayakaran; Vaseghi, Reza

    2014-01-01

    The current paper presented theoretical assumptions behind language learning strategies (LLS) and an overview of methods used to identify learners' strategies, first, and then summarized what have been reported from large number of descriptive studies of strategies by language learners. Moreover, the paper tried to present the variety of…

  4. Nondestructive Testing Eddy Current Equipment, Methods and Applications RQA/M1-5330.12 (V-II).

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Huntsville, AL. George C. Marshall Space Flight Center.

    As one in the series of programmed instruction handbooks, prepared by the U. S. space program, home study material is presented in this volume concerning familiarization and orientation on eddy current testing. The subject is presented under the following headings: Test Coils, Methods and Indications, and Applications. High product quality and…

  5. Overview of ECRH experimental results

    NASA Astrophysics Data System (ADS)

    Lloyd, Brian

    1998-08-01

    A review of the present status of electron cyclotron heating and current drive experiments in toroidal fusion devices is presented. In addition to basic heating and current drive studies the review also addresses advances in wave physics and the application of electron cyclotron waves for instability control, transport studies, pre-ionization/start-up assist, etc. A comprehensive overview is given with particular emphasis on recent advances since the major review of Erckmann and Gasparino (1994) ( 36 1869), including results from the latest generation of high-power, high-frequency experiments.

  6. Do Magnetic Fields Drive High-Energy Explosive Transients?

    NASA Astrophysics Data System (ADS)

    Mundell, Carole

    2017-10-01

    I will review the current state-of-the-art in real-time, rapid response optical imaging and polarimetric followup of transient sources such as Gamma Ray Bursts. I will interpret current results within the context of the external shock model and present predictions for future mm- and cm-wave radio observatories. Recent observational results from new radio pilot studies will also be presented.

  7. Land Combat Systems Industry Study 2004

    DTIC Science & Technology

    2004-01-01

    David Barnhart, Florida Air National Guard Lt Col Warren Anderson, United States Air Force Lt Col Phillip Chudoba, United States Marine Corps Mr...beginning with the current condition of GD. CURRENT CONDITION In the business world, the rearview mirror is always clearer than the windshield. Warren ... Buffett The ICAF coursework and field trips presented the study team with ample historic data for assessing the current condition of the LCS firms

  8. Matching, Demand, Maximization, and Consumer Choice

    ERIC Educational Resources Information Center

    Wells, Victoria K.; Foxall, Gordon R.

    2013-01-01

    The use of behavioral economics and behavioral psychology in consumer choice has been limited. The current study extends the study of consumer behavior analysis, a synthesis between behavioral psychology, economics, and marketing, to a larger data set. This article presents the current work and results from the early analysis of the data. We…

  9. Asteroid Redirect Crewed Mission Space Suit and EVA System Architecture Trade Study

    NASA Technical Reports Server (NTRS)

    Bowie, Jonathan T.; Blanco, Raul A.; Watson, Richard D.; Kelly, Cody; Buffington, Jesse; Sipila, Stephanie A.

    2014-01-01

    This paper discusses the Asteroid Redirect Crewed Mission (ARCM) space suit and Extravehicular Activity (EVA) architecture trade study and the current state of the work to mature the requirements and products to the mission concept review level. The mission requirements and the resulting concept of operations will be discussed. A historical context will be presented as to present the similarities and differences from previous NASA missions. That will set the stage for the trade study where all options for both pressure garment and life support were considered. The rationale for the architecture decisions will then be presented. Since the trade study did identity risks, the subsequent tests and analyses that mitigated the risks will be discussed. Lastly, the current state of the effort will be provided.

  10. A Study of the Implementation of Current Cost Accounting in the Republic of Korea Army Procurement Systems.

    DTIC Science & Technology

    1986-06-01

    financial reporting in Republic of Korea Army (ROKA) procurement. A discussion of the nature of the ROKA procurement system and two alternatives to historical cost financial statements are presented. The concepts, methods and procedures of the historical cost/constant dollars financial statements are described. The proposal for current cost/constant dollars financial statements is presented and emphasis is given to the description of four problems in existing ROKA procurement due to using inadequate accounting information. Keywords: Cost accounting, Procurement, Current

  11. Parametrically Optimized Carbon Nanotube-Coated Cold Cathode Spindt Arrays

    PubMed Central

    Yuan, Xuesong; Cole, Matthew T.; Zhang, Yu; Wu, Jianqiang; Milne, William I.; Yan, Yang

    2017-01-01

    Here, we investigate, through parametrically optimized macroscale simulations, the field electron emission from arrays of carbon nanotube (CNT)-coated Spindts towards the development of an emerging class of novel vacuum electron devices. The present study builds on empirical data gleaned from our recent experimental findings on the room temperature electron emission from large area CNT electron sources. We determine the field emission current of the present microstructures directly using particle in cell (PIC) software and present a new CNT cold cathode array variant which has been geometrically optimized to provide maximal emission current density, with current densities of up to 11.5 A/cm2 at low operational electric fields of 5.0 V/μm. PMID:28336845

  12. The Development of the Unified Protocol for the Transdiagnostic Treatment of Emotional Disorders: A Case Study

    PubMed Central

    Boisseau, Christina L.; Farchione, Todd J.; Fairholme, Christopher P.; Ellard, Kristen K.; Barlow, David H.

    2013-01-01

    A detailed description of treatment utilizing the Unified Protocol (UP), a transdiagnostic emotion-focused cognitive-behavioral treatment, is presented using a clinical case example treated during the most current phase of an ongoing randomized controlled trial of the UP. The implementation of the UP in its current, modular version is illustrated. A working case conceptualization is presented from the perspective of the UP drawing from theory and research that underlies current transdiagnostic approaches to treatment and consistent with recent dimensional classification proposals (Brown & Barlow, in press). Treatment is illustrated module-by-module describing how the principles of the UP were applied in the presented case. PMID:23997572

  13. On the recovery of electric currents in the liquid core of the Earth

    NASA Astrophysics Data System (ADS)

    Kuslits, Lukács; Prácser, Ernő; Lemperger, István

    2017-04-01

    Inverse geodynamo modelling has become a standard method to get a more accurate image of the processes within the outer core. In this poster excerpts from the preliminary results of an other approach are presented. This comes around the possibility of recovering the currents within the liquid core directly, using Main Magnetic Field data. The approximation of different systems of the flow of charge is possible with various geometries. Based on previous geodynamo simulations, current coils can furnish a good initial geometry for such an estimation. The presentation introduces our preliminary test results and the study of reliability of the applied inversion algorithm for different numbers of coils, distributed in a grid simbolysing the domain between the inner-core and core-mantle boundaries. We shall also present inverted current structures using Main Field model data.

  14. Associations of smoking status with other lifestyle behaviors are modified by sex and occupational category among urban civil servants in Japan.

    PubMed

    Higashibata, Takahiro; Wakai, Kenji; Okada, Rieko; Nakagawa, Hiroko; Hamajima, Nobuyuki

    2016-11-01

    The aim of the present study was to examine the associations of current smoking with five other unhealthy lifestyle behaviors among urban civil servants in Japan according to sex and occupational category. The study included 10,232 urban civil servants in Japan who presented for a health check-up in 2011. We analyzed data on anthropometric measurements and self-reported lifestyle factors. Current smokers had a higher BMI than never smokers in white-collar workers, but not in blue-collar workers of both sexes. There were strong associations of current smoking with irregular breakfasting regardless of sex and occupational category. In males, current smokers were less likely to take exercise than ex-smokers in both occupational categories. The associations of current smoking with other unhealthy behaviors were modified by sex and occupational category. These results are useful for understanding the health risks among smokers according to sex and occupational category.

  15. Mitigation of eddy current heating during magnetic nanoparticle hyperthermia therapy.

    PubMed

    Stigliano, Robert V; Shubitidze, Fridon; Petryk, James D; Shoshiashvili, Levan; Petryk, Alicia A; Hoopes, P Jack

    2016-11-01

    Magnetic nanoparticle hyperthermia therapy is a promising technology for cancer treatment, involving delivering magnetic nanoparticles (MNPs) into tumours then activating them using an alternating magnetic field (AMF). The system produces not only a magnetic field, but also an electric field which penetrates normal tissue and induces eddy currents, resulting in unwanted heating of normal tissues. Magnitude of the eddy current depends, in part, on the AMF source and the size of the tissue exposed to the field. The majority of in vivo MNP hyperthermia therapy studies have been performed in small animals, which, due to the spatial distribution of the AMF relative to the size of the animals, do not reveal the potential toxicity of eddy current heating in larger tissues. This has posed a non-trivial challenge for researchers attempting to scale up to clinically relevant volumes of tissue. There is a relative dearth of studies focused on decreasing the maximum temperature resulting from eddy current heating to increase therapeutic ratio. This paper presents two simple, clinically applicable techniques for decreasing maximum temperature induced by eddy currents. Computational and experimental results are presented to understand the underlying physics of eddy currents induced in conducting, biological tissues and leverage these insights to mitigate eddy current heating during MNP hyperthermia therapy. Phantom studies show that the displacement and motion techniques reduce maximum temperature due to eddy currents by 74% and 19% in simulation, and by 77% and 33% experimentally. Further study is required to optimise these methods for particular scenarios; however, these results suggest larger volumes of tissue could be treated, and/or higher field strengths and frequencies could be used to attain increased MNP heating when these eddy current mitigation techniques are employed.

  16. Scientific progress - wireless phones and brain cancer: current state of the science.

    PubMed

    Carlo, G L; Jenrow, R S

    2000-07-11

    The current science is not definitive about health risks from wireless phones; however, the legitimate questions about safety that have arisen from recent studies make claims of absolute safety no longer supportable. The objective of this paper is to outline for primary care providers the results of the most current research on the possible impact of wireless phone use on human health. Presented are study results from Wireless Technology Research (WTR) program, the 7-year, $27 million effort funded by the wireless industry in the United States, that represents the world's most comprehensive research effort addressing this issue to date. Science-based recommendations for consumer interventions and future research are presented. Original studies performed under the WTR program as well as other relevant research from around the world. This article presents a synopsis of the peer-reviewed in vitro and in vivo laboratory research, and the peer-reviewed epidemiology studies supported by the WTR, as well as a summary of other relevant work. Only peer-reviewed scientific studies are presented, primarily WTR-sponsored research. In addition, results of the WTR literature surveillance program, which identified other relevant toxicology and epidemiology studies on an ongoing basis, are presented. These studies are presented in the context of their usefulness in providing intervention recommendations for consumers. Following a qualitative synthesis of specific relevant non-WTR research and a critical assessment of the WTR results, the following represents the current state of scientific understanding relevant to the public health impact of wireless phones: laboratory studies appear to have confirmed that radio frequency radiation from wireless phone antennas is insufficient to cause DNA breakage; however, this same radiation appears to cause genetic damage in human blood as measured through the formation of micronuclei. An increase in the rate of brain cancer mortality among hand-held cellular phone users as compared to car phone users, though not statistically significant, was observed in the WTR cohort study. A statistically significant increase in the risk of neuro-epithelial brain tumors was observed among cellular phone users in another case-control study. As new data emerge, our understanding of this complex problem will improve; however, at present there is a critical need for ongoing and open evaluation of the public health impact of new science, and communication of this science and derivative intervention options to those who are potentially affected.

  17. A Current Events Approach to Academic Reading.

    ERIC Educational Resources Information Center

    Hirsch, Sharon F.; Gabbay, Anita

    1995-01-01

    Presents a current events course designed to teach students in Israel both English language skills as well as the advanced reading and study skills they need to comprehend university level texts and journal articles. A current events approach to academic reading enlivens the foreign language classroom and motivates and broadens the horizons of…

  18. Studies on space charge neutralization and emittance measurement of beam from microwave ion source.

    PubMed

    Misra, Anuraag; Goswami, A; Sing Babu, P; Srivastava, S; Pandit, V S

    2015-11-01

    A 2.45 GHz microwave ion source together with a beam transport system has been developed at VECC to study the problems related with the injection of high current beam into a compact cyclotron. This paper presents the results of beam profile measurement of high current proton beam at different degrees of space charge neutralisation with the introduction of neon gas in the beam line using a fine leak valve. The beam profiles have been measured at different pressures in the beam line by capturing the residual gas fluorescence using a CCD camera. It has been found that with space charge compensation at the present current level (∼5 mA at 75 keV), it is possible to reduce the beam spot size by ∼34%. We have measured the variation of beam profile as a function of the current in the solenoid magnet under the neutralised condition and used these data to estimate the rms emittance of the beam. Simulations performed using equivalent Kapchinsky-Vladimirsky beam envelope equations with space charge neutralization factor are also presented to interpret the experimental results.

  19. Studies on space charge neutralization and emittance measurement of beam from microwave ion source

    NASA Astrophysics Data System (ADS)

    Misra, Anuraag; Goswami, A.; Sing Babu, P.; Srivastava, S.; Pandit, V. S.

    2015-11-01

    A 2.45 GHz microwave ion source together with a beam transport system has been developed at VECC to study the problems related with the injection of high current beam into a compact cyclotron. This paper presents the results of beam profile measurement of high current proton beam at different degrees of space charge neutralisation with the introduction of neon gas in the beam line using a fine leak valve. The beam profiles have been measured at different pressures in the beam line by capturing the residual gas fluorescence using a CCD camera. It has been found that with space charge compensation at the present current level (˜5 mA at 75 keV), it is possible to reduce the beam spot size by ˜34%. We have measured the variation of beam profile as a function of the current in the solenoid magnet under the neutralised condition and used these data to estimate the rms emittance of the beam. Simulations performed using equivalent Kapchinsky-Vladimirsky beam envelope equations with space charge neutralization factor are also presented to interpret the experimental results.

  20. Some Student Conceptions of Electromagnetic Induction

    NASA Astrophysics Data System (ADS)

    Thong, Wai Meng; Gunstone, Richard

    2008-01-01

    Introductory electromagnetism is a central part of undergraduate physics. Although there has been some research into student conceptions of electromagnetism, studies have been sparse and separated. This study sought to explore second year physics students’ conceptions of electromagnetism, to investigate to what extent the results from the present study are similar to these results from other studies, and to uncover any new forms of alternative conceptions. Data for this study came from 15 in-depth interviews. Three previously unreported alternative conceptions were identified in the study: 1) induced current varies proportionately with current in solenoid; 2) there must be contact between magnetic flux and the external coil in order for any emf to be induced in the coil; 3) coulombic or electrostatic potential difference is present in an induced electric field. These alternative conceptions were manifested in these students’ explanations of electromagnetic phenomena presented to them during the interviews.

  1. Bootstrap and fast wave current drive for tokamak reactors

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

    Ehst, D.A.

    1991-09-01

    Using the multi-species neoclassical treatment of Hirshman and Sigmar we study steady state bootstrap equilibria with seed currents provided by low frequency (ICRF) fast waves and with additional surface current density driven by lower hybrid waves. This study applies to reactor plasmas of arbitrary aspect ratio. IN one limit the bootstrap component can supply nearly the total equilibrium current with minimal driving power (< 20 MW). However, for larger total currents considerable driving power is required (for ITER: I{sub o} = 18 MA needs P{sub FW} = 15 MW, P{sub LH} = 75 MW). A computational survey of bootstrap fractionmore » and current drive efficiency is presented. 11 refs., 8 figs.« less

  2. Advanced electric propulsion research - 1990

    NASA Technical Reports Server (NTRS)

    Monheiser, Jeffery M.; Wilbur, Paul J.

    1991-01-01

    An experimental study of impingement current collection on the accelerator grid of an ion thruster is presented. The equipment, instruments, and procedures being used to conduct the study are discussed. The contribution to this current due to charge-exchange ions produced close to the grid is determined using a volume-integration procedure and measured ion beam current design, computed neutral atom density and measured beam plasma potential data. This current, which is expected to be almost equal to that measured directly, is found to be an order of magnitude less. The impingement current determined by integrating the current density of ambient ions in the beam plasma close to the grid is found to agree with the directly measured impingement current. Possible reasons for the disagreement between the directly measured and volume integrated impingement currents are discussed.

  3. INEL BNCT Research Program, March/April 1992

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

    Venhuizen, J.R.

    1992-09-01

    This report presents summaries for two months of current research for the Idaho National Engineering Laboratory (INEL) Boron Neutron Capture Therapy (BNCT) Program. Information is presented on development and murino screening experiments of low-density lipoprotein, carboranyl alanine, and liposome boron containing compounds. Pituitary tumor call culture studies are described. Drug stability, pharmacology and toxicity evaluation of borocaptate sodium (BSH) and boronopheoylalanine (BPA) are described. Treatment protocol development via the large animal (canine) model studies and physiological response evaluation in rats are discussed. Supporting technology development and technical support activities for boron drug biochemistry and purity, analytical and measurement dosimetry, andmore » noninvasive boron quantification activities are included for the current time period. Current publications for the two months are listed.« less

  4. 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.

  5. Conceptual Design of a 100kW Energy Integrated Type Bi-Directional Tidal Current Turbine

    NASA Astrophysics Data System (ADS)

    Kim, Ki Pyoung; Ahmed, M. Rafiuddin; Lee, Young Ho

    2010-06-01

    The development of a tidal current turbine that can extract maximum energy from the tidal current will be extremely beneficial for supplying continuous electric power. The present paper presents a conceptual design of a 100kW energy integrated type tidal current turbine for tidal power generation. The instantaneous power density of a flowing fluid incident on an underwater turbine is proportional to the cubic power of current velocity which is approximately 2.5m/s. A cross-flow turbine, provided with a nozzle and a diffuser, is designed and analyzed. The potential advantages of ducted and diffuser-augmented turbines were taken into consideration in order to achieve higher output at a relatively low speed. This study looks at a cross-flow turbine system which is placed in an augmentation channel to generate electricity bi-directionally. The compatibility of this turbine system is verified using a commercial CFD code, ANSYSCFX. This paper presents the results of the numerical analysis in terms of pressure, streaklines, velocity vectors and performance curves for energy integrated type bi-directional tidal current turbine (BDT) with augmentation.

  6. Conceptualization of Depth of Vocabulary Knowledge with Academic Reading Comprehension

    ERIC Educational Resources Information Center

    Hasan, Md. Kamrul; Shabdin, Ahmad Affendi

    2016-01-01

    The present study embodies a conceptual framework, and it studies the concept regarding the depth of vocabulary knowledge. Literature review is employed as a foundation for developing the conceptual framework for the present study. The current study suggests that different dimensions of depth of vocabulary knowledge, namely paradigmatic relations,…

  7. A Portfolio of Energy Ideas: Social Studies.

    ERIC Educational Resources Information Center

    Clark, Richard C., Ed.

    Presented are 12 social studies units which examine current energy issues and present energy dilemmas for careful study and reflection. The activities emphasize: (1) a range of teaching strategies; (2) problem identification, problem solving, and problem analysis; (3) futures education; (4) students as active learners; and (5) consideration of the…

  8. Re-bordering comparative education in Latin America: Between global limits and local characteristics

    NASA Astrophysics Data System (ADS)

    Acosta, Felicitas; Perez Centeno, Cristian G.

    2011-08-01

    Conceived for presentation at the XIV WCCES conference in Istanbul in 2010, the topic of which was "Bordering Comparative Education", this paper, within that framework, aims to present the current state of the discipline in Latin America in relation to a quick overview of its present-day situation at a global level. After providing an overview of the current debates on comparative education, with special emphasis on what the authors refer to as motor nuclei (a series of milestones or episodes which have become transdiscursive as the discipline has evolved), as well as pinpointing current challenges in the field, this paper looks into the development of the discipline in Latin America and how it has contributed to the understanding of the region's educational systems. The paper also examines the unique relationship between comparative studies and the field of educational planning in Latin America. The authors then go on to provide a thematic analysis, categorising the papers presented at three conferences held by the Sociedad Argentina de Estudios Comparados en Educación (SAECE, the Argentine Society for Comparative Education Studies) in 2005, 2007 and 2009. The paper closes with several conclusions regarding the current debate on the discipline in the region and its possibilities for the future.

  9. Fracture mechanics /Dryden Lecture/. [aerospace structural design applications

    NASA Technical Reports Server (NTRS)

    Hardrath, H. F.

    1974-01-01

    A historical outline of the engineering discipline of fracture mechanics is presented, and current analytical procedures are summarized. The current status of the discipline is assessed, and engineering applications are discussed, along with recommended directions for future study.

  10. Large Eddy Simulations of sediment entrainment induced by a lock-exchange gravity current

    NASA Astrophysics Data System (ADS)

    Kyrousi, Foteini; Leonardi, A.; Roman, F.; Armenio, V.; Zanello, F.; Zordan, J.; Juez, C.; Falcomer, L.

    2018-04-01

    Large Eddy simulations of lock-exchange gravity currents propagating over a mobile reach are presented. The numerical setting allows to investigate the sediment pick up induced by the currents and to study the underlying mechanisms leading to sediment entrainment for different Grashof numbers and grain sizes. First, the velocity field and the bed shear-stress distribution are investigated, along with turbulent structures formed in the flow, before the current reaches the mobile bed. Then, during the propagation of the current above the erodible section of the bed the contour plots of the entrained material are presented as well as the time evolution of the areas covered by the current and by the sediment at this section. The numerical outcomes are compared with experimental data showing a very good agreement. Overall, the study confirms that sediment pick up is prevalent at the head of the current where the strongest turbulence occurs. Further, above the mobile reach of the bed, settling process seems to be of minor importance, with the entrained material being advected downstream by the current. Additionally, the study shows that, although shear stress is the main mechanism that sets particles in motion, turbulent bursts as well as vertical velocity fluctuations are also necessary to counteract the falling velocity of the particles and maintain them into suspension. Finally, the analysis of the stability conditions of the current shows that, from one side, sediment concentration gives a negligible contribution to the stability of the front of the current and from the other side, the stability conditions provided by the current do not allow sediments to move into the ambient fluid.

  11. On wind-wave-current interactions during the Shoaling Waves Experiment

    NASA Astrophysics Data System (ADS)

    Zhang, Fei W.; Drennan, William M.; Haus, Brian K.; Graber, Hans C.

    2009-01-01

    This paper presents a case study of wind-wave-current interaction during the Shoaling Waves Experiment (SHOWEX). Surface current fields off Duck, North Carolina, were measured by a high-frequency Ocean Surface Current Radar (OSCR). Wind, wind stress, and directional wave data were obtained from several Air Sea Interaction Spar (ASIS) buoys moored in the OSCR scanning domain. At several times during the experiment, significant coastal currents entered the experimental area. High horizontal shears at the current edge resulted in the waves at the peak of wind-sea spectra (but not those in the higher-frequency equilibrium range) being shifted away from the mean wind direction. This led to a significant turning of the wind stress vector away from the mean wind direction. The interactions presented here have important applications in radar remote sensing and are discussed in the context of recent radar imaging models of the ocean surface.

  12. Influence of Hall Current and Viscous Dissipation on Pressure Driven Flow of Pseudoplastic Fluid with Heat Generation: A Mathematical Study.

    PubMed

    Noreen, Saima; Qasim, Muhammad

    2015-01-01

    In this paper, we study the influence of heat sink (or source) on the peristaltic motion of pseudoplastic fluid in the presence of Hall current, where channel walls are non-conducting in nature. Flow analysis has been carried out under the approximations of a low Reynolds number and long wavelength. Coupled equations are solved using shooting method for numerical solution for the axial velocity function, temperature and pressure gradient distributions. We analyze the influence of various interesting parameters on flow quantities. The present study can be considered as a mathematical presentation of the dynamics of physiological organs with stones.

  13. 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)

  14. Reading Time Allocation Strategies and Working Memory Using Rapid Serial Visual Presentation

    ERIC Educational Resources Information Center

    Busler, Jessica N.; Lazarte, Alejandro A.

    2017-01-01

    Rapid serial visual presentation (RSVP) is a useful method for controlling the timing of text presentations and studying how readers' characteristics, such as working memory (WM) and reading strategies for time allocation, influence text recall. In the current study, a modified version of RSVP (Moving Window RSVP [MW-RSVP]) was used to induce…

  15. Statistical Comparisons of Meso- and Small-Scale Field-Aligned Currents with Auroral Electron Acceleration Mechanisms from FAST Observations

    NASA Astrophysics Data System (ADS)

    Dombeck, J. P.; Cattell, C. A.; Prasad, N.; Sakher, A.; Hanson, E.; McFadden, J. P.; Strangeway, R. J.

    2016-12-01

    Field-aligned currents (FACs) provide a fundamental driver and means of Magnetosphere-Ionosphere (M-I) coupling. These currents need to be supported by local physics along the entire field line generally with quasi-static potential structures, but also supporting the time-evolution of the structures and currents, producing Alfvén waves and Alfvénic electron acceleration. In regions of upward current, precipitating auroral electrons are accelerated earthward. These processes can result in ion outflow, changes in ionospheric conductivity, and affect the particle distributions on the field line, affecting the M-I coupling processes supporting the individual FACs and potentially the entire FAC system. The FAST mission was well suited to study both the FACs and the electron auroral acceleration processes. We present the results of the comparisons between meso- and small-scale FACs determined from FAST using the method of Peria, et al., 2000, and our FAST auroral acceleration mechanism study when such identification is possible for the entire ˜13 year FAST mission. We also present the latest results of the electron energy (and number) flux ionospheric input based on acceleration mechanism (and FAC characteristics) from our FAST auroral acceleration mechanism study.

  16. Modeling the Inner Magnetosphere: Radiation Belts, Ring Current, and Composition

    NASA Technical Reports Server (NTRS)

    Glocer, Alex

    2011-01-01

    The space environment is a complex system defined by regions of differing length scales, characteristic energies, and physical processes. It is often difficult, or impossible, to treat all aspects of the space environment relative to a particular problem with a single model. In our studies, we utilize several models working in tandem to examine this highly interconnected system. The methodology and results will be presented for three focused topics: 1) Rapid radiation belt electron enhancements, 2) Ring current study of Energetic Neutral Atoms (ENAs), Dst, and plasma composition, and 3) Examination of the outflow of ionospheric ions. In the first study, we use a coupled MHD magnetosphere - kinetic radiation belt model to explain recent Akebono/RDM observations of greater than 2.5 MeV radiation belt electron enhancements occurring on timescales of less than a few hours. In the second study, we present initial results of a ring current study using a newly coupled kinetic ring current model with an MHD magnetosphere model. Results of a dst study for four geomagnetic events are shown. Moreover, direct comparison with TWINS ENA images are used to infer the role that composition plays in the ring current. In the final study, we directly model the transport of plasma from the ionosphere to the magnetosphere. We especially focus on the role of photoelectrons and and wave-particle interactions. The modeling methodology for each of these studies will be detailed along with the results.

  17. Superconducting Magnetometry for Cardiovascular Studies and AN Application of Adaptive Filtering.

    NASA Astrophysics Data System (ADS)

    Leifer, Mark Curtis

    Sensitive magnetic detectors utilizing Superconducting Quantum Interference Devices (SQUID's) have been developed and used for studying the cardiovascular system. The theory of magnetic detection of cardiac currents is discussed, and new experimental data supporting the validity of the theory is presented. Measurements on both humans and dogs, in both healthy and diseased states, are presented using the new technique, which is termed vector magnetocardiography. In the next section, a new type of superconducting magnetometer with a room temperature pickup is analyzed, and techniques for optimizing its sensitivity to low-frequency sub-microamp currents are presented. Performance of the actual device displays significantly improved sensitivity in this frequency range, and the ability to measure currents in intact, in vivo biological fibers. The final section reviews the theoretical operation of a digital self-optimizing filter, and presents a four-channel software implementation of the system. The application of the adaptive filter to enhancement of geomagnetic signals for earthquake forecasting is discussed, and the adaptive filter is shown to outperform existing techniques in suppressing noise from geomagnetic records.

  18. Study of an Audio Playback Machine Storage, Distribution, and Repair System. Options for Machine Operation. Study II, Part 1, Phase 2, Final Report.

    ERIC Educational Resources Information Center

    ManTech Technical Services Corp., Fairfax, VA.

    This report presents the results of a management study of audio playback equipment operations conducted by the National Library Service, Library of Congress, its associated network of state and local machine lending agencies (MLA), and other parties that play a role in current operations. The objectives were to document current operations,…

  19. Eddy Current System for Detection of Cracking Beneath Braiding in Corrugated Metal Hose

    NASA Astrophysics Data System (ADS)

    Wincheski, Buzz; Simpson, John; Hall, George

    2009-03-01

    In this paper an eddy current system for the detection of partially-through-the-thickness cracks in corrugated metal hose is presented. Design criteria based upon the geometry and conductivity of the part are developed and applied to the fabrication of a prototype inspection system. Experimental data are used to highlight the capabilities of the system and an image processing technique is presented to improve flaw detection capabilities. A case study for detection of cracking damage in a space shuttle radiator retract flex hoses is also presented.

  20. Eddy Current System for Detection of Cracking Beneath Braiding in Corrugated Metal Hose

    NASA Technical Reports Server (NTRS)

    Wincheski, Buzz; Simpson, John; Hall, George

    2008-01-01

    In this paper an eddy current system for the detection of partially-through-the-thickness cracks in corrugated metal hose is presented. Design criteria based upon the geometry and conductivity of the part are developed and applied to the fabrication of a prototype inspection system. Experimental data are used to highlight the capabilities of the system and an image processing technique is presented to improve flaw detection capabilities. A case study for detection of cracking damage in a space shuttle radiator retract flex hoses is also presented.

  1. Current Trends in Microform Use by Secondary Schools: Four Case Studies.

    ERIC Educational Resources Information Center

    Lee, Thomas Graham

    The case study section of this booklet discusses a number of current microform programs in secondary schools. The remainder of the booklet presents an overview of microform activity, including comments on the history of secondary school microform utilization and an up-to-date listing of microform selection aids. The amount of information available…

  2. NOTE Effects of skeletal muscle anisotropy on induced currents from low-frequency magnetic fields

    NASA Astrophysics Data System (ADS)

    Tachas, Nikolaos J.; Samaras, Theodoros; Baskourelos, Konstantinos; Sahalos, John N.

    2009-12-01

    Studies which take into account the anisotropy of tissue dielectric properties for the numerical assessment of induced currents from low-frequency magnetic fields are scarce. In the present study, we compare the induced currents in two anatomical models, using the impedance method. In the first model, we assume that all tissues have isotropic conductivity, whereas in the second one, we assume anisotropic conductivity for the skeletal muscle. Results show that tissue anisotropy should be taken into account when investigating the exposure to low-frequency magnetic fields, because it leads to higher induced current values.

  3. 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

  4. 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.

  5. Breaking the Illiteracy Bonds.

    ERIC Educational Resources Information Center

    Taylor, Susan Champlin

    1988-01-01

    Describes current research being done on literacy and discusses reasons behind the varied estimates of adult literacy rates. Presents several case studies of adults who are currently or have been in reading programs, particularly older adults. Describes the work of major literacy education providers. (CH)

  6. Non-invasive brain stimulation and computational models in post-stroke aphasic patients: single session of transcranial magnetic stimulation and transcranial direct current stimulation. A randomized clinical trial.

    PubMed

    Santos, Michele Devido Dos; Cavenaghi, Vitor Breseghello; Mac-Kay, Ana Paula Machado Goyano; Serafim, Vitor; Venturi, Alexandre; Truong, Dennis Quangvinh; Huang, Yu; Boggio, Paulo Sérgio; Fregni, Felipe; Simis, Marcel; Bikson, Marom; Gagliardi, Rubens José

    2017-01-01

    Patients undergoing the same neuromodulation protocol may present different responses. Computational models may help in understanding such differences. The aims of this study were, firstly, to compare the performance of aphasic patients in naming tasks before and after one session of transcranial direct current stimulation (tDCS), transcranial magnetic stimulation (TMS) and sham, and analyze the results between these neuromodulation techniques; and secondly, through computational model on the cortex and surrounding tissues, to assess current flow distribution and responses among patients who received tDCS and presented different levels of results from naming tasks. Prospective, descriptive, qualitative and quantitative, double blind, randomized and placebo-controlled study conducted at Faculdade de Ciências Médicas da Santa Casa de São Paulo. Patients with aphasia received one session of tDCS, TMS or sham stimulation. The time taken to name pictures and the response time were evaluated before and after neuromodulation. Selected patients from the first intervention underwent a computational model stimulation procedure that simulated tDCS. The results did not indicate any statistically significant differences from before to after the stimulation.The computational models showed different current flow distributions. The present study did not show any statistically significant difference between tDCS, TMS and sham stimulation regarding naming tasks. The patients'responses to the computational model showed different patterns of current distribution.

  7. Determining the near-surface current profile from measurements of the wave dispersion relation

    NASA Astrophysics Data System (ADS)

    Smeltzer, Benjamin; Maxwell, Peter; Aesøy, Eirik; Ellingsen, Simen

    2017-11-01

    The current-induced Doppler shifts of waves can yield information about the background mean flow, providing an attractive method of inferring the current profile in the upper layer of the ocean. We present measurements of waves propagating on shear currents in a laboratory water channel, as well as theoretical investigations of inversion techniques for determining the vertical current structure. Spatial and temporal measurements of the free surface profile obtained using a synthetic Schlieren method are analyzed to determine the wave dispersion relation and Doppler shifts as a function of wavelength. The vertical current profile can then be inferred from the Doppler shifts using an inversion algorithm. Most existing algorithms rely on a priori assumptions of the shape of the current profile, and developing a method that uses less stringent assumptions is a focus of this study, allowing for measurement of more general current profiles. The accuracy of current inversion algorithms are evaluated by comparison to measurements of the mean flow profile from particle image velocimetry (PIV), and a discussion of the sensitivity to errors in the Doppler shifts is presented.

  8. Initial Technology Assessment for the Large-Aperture UV-Optical-Infrared (LUVOIR) Mission Concept Study

    NASA Technical Reports Server (NTRS)

    Bolcar, Matthew R.; Feinberg, Lee; France, Kevin; Rauscher, Bernard J.; Redding, David; Schiminovich, David

    2016-01-01

    The NASA Astrophysics Division's 30-Year Roadmap prioritized a future large-aperture space telescope operating in the ultra-violet/optical/infrared wavelength regime. The Association of Universities for Research in Astronomy envisioned a similar observatory, the High Definition Space Telescope. And a multi-institution group also studied the Advanced Technology Large Aperture Space Telescope. In all three cases, a broad science case is outlined, combining general astrophysics with the search for biosignatures via direct-imaging and spectroscopic characterization of habitable exoplanets. We present an initial technology assessment that enables such an observatory that is currently being studied for the 2020 Decadal Survey by the Large UV/Optical/Infrared (LUVOIR) surveyor Science and Technology Definition Team. We present here the technology prioritization for the 2016 technology cycle and define the required technology capabilities and current state-of-the-art performance. Current, planned, and recommended technology development efforts are also reported.

  9. Initial Technology Assessment for the Large UV-Optical-Infrared (LUVOIR) Mission Concept Study

    NASA Technical Reports Server (NTRS)

    Bolcar, Matthew R.; Feinberg, Lee D.; France, Kevin; Rauscher, Bernard J.; Redding, David; Schiminovich, David

    2016-01-01

    The NASA Astrophysics Divisions 30-Year Roadmap prioritized a future large-aperture space telescope operating in the ultra-violet-optical-infrared wavelength regime. The Association of Universities for Research in Astronomy envisioned a similar observatory, the High Definition Space Telescope. And a multi-institution group also studied the Advanced Technology Large Aperture Space Telescope. In all three cases, a broad science case is outlined, combining general astrophysics with the search for bio-signatures via direct-imaging and spectroscopic characterization of habitable exo-planets. We present an initial technology assessment that enables such an observatory that is currently being studied for the 2020 Decadal Survey by the Large UV-Optical Infrared (LUVOIR) surveyor Science and Technology Definition Team. We present here the technology prioritization for the 2016 technology cycle and define the required technology capabilities and current state-of-the-art performance. Current, planned, and recommended technology development efforts are also reported.

  10. Estimating Advective Near-surface Currents from Ocean Color Satellite Images

    DTIC Science & Technology

    2015-01-01

    of surface current information. The present study uses the sequential ocean color products provided by the Geostationary Ocean Color Imager (GOCI) and...on the SuomiNational Polar-Orbiting Partner- ship (S-NPP) satellite. The GOCI is the world’s first geostationary orbit satellite sensor over the...used to extract the near-surface currents by the MCC algorithm. We not only demonstrate the retrieval of currents from the geostationary satellite ocean

  11. Word Processing in Elementary Schools: Seven Case Studies. Education and Technology Series.

    ERIC Educational Resources Information Center

    Murray, Jack; And Others

    As a result of preliminary observations of word processing in elementary level language the seven case studies presented in this report reveal the effectiveness of current word processing (WP) activities within their respective instructional contexts. Each study is presented separately, detailing the classroom context, tasks and outcomes, program…

  12. Influence of the substorm current wedge on the Dst index

    NASA Astrophysics Data System (ADS)

    Friedrich, Erena; Rostoker, Gordon; Connors, Martin G.; McPherron, R. L.

    1999-03-01

    One of the major questions confronting researchers studying the nature of the solar-terrestrial interaction centers around whether or not the substorm expansive phase has any causal effect on the growth of the storm time ring current. This question is often addressed by using the Dst index as a proxy for the storm time ring current and inspecting the main phase growth of Dst in the context of the substorm expansive phases which occur in the same time frame as the ring current growth. In the past it has been assumed that the magnetic effects of the substorm current wedge have little influence on the Dst index because the current wedge is an asymmetric current system, while Dst is supposed to reflect changes in the symmetric component of the ring current. In this paper we shall shown that the substorm current wedge can have a significant effect on the present Dst index, primarily as a consequence of the fact that only four stations are presently used to formulate the index. Calculations are made assuming the instantaneous magnitude of the wedge current is constant at 1 MA. Hourly values of Dst may be as much as 50° smaller than those presented here because of variation of the wedge current over the hour. We shall show how the effect of the current wedge depends on the UT of the expansive phase onset, the angular extent of the current wedge, and the locale of the closure current in the magnetosphere. The fact that the substorm current wedge is a conjugate phenomenon has an important influence on the magnitude of the expansive phase effect in the Dst index.

  13. Measurement of neoclassically predicted edge current density at ASDEX Upgrade

    NASA Astrophysics Data System (ADS)

    Dunne, M. G.; McCarthy, P. J.; Wolfrum, E.; Fischer, R.; Giannone, L.; Burckhart, A.; the ASDEX Upgrade Team

    2012-12-01

    Experimental confirmation of neoclassically predicted edge current density in an ELMy H-mode plasma is presented. Current density analysis using the CLISTE equilibrium code is outlined and the rationale for accuracy of the reconstructions is explained. Sample profiles and time traces from analysis of data at ASDEX Upgrade are presented. A high time resolution is possible due to the use of an ELM-synchronization technique. Additionally, the flux-surface-averaged current density is calculated using a neoclassical approach. Results from these two separate methods are then compared and are found to validate the theoretical formula. Finally, several discharges are compared as part of a fuelling study, showing that the size and width of the edge current density peak at the low-field side can be explained by the electron density and temperature drives and their respective collisionality modifications.

  14. Effect of surface tension on the behavior of adhesive contact based on Lennard-Jones potential law

    NASA Astrophysics Data System (ADS)

    Zhu, Xinyao; Xu, Wei

    2018-02-01

    The present study explores the effect of surface tension on adhesive contact behavior where the adhesion is interpreted by long-range intermolecular forces. The adhesive contact is analyzed using the equivalent system of a rigid sphere and an elastic half space covered by a membrane with surface tension. The long-range intermolecular forces are modeled with the Lennard‒Jones (L‒J) potential law. The current adhesive contact issue can be represented by a nonlinear integral equation, which can be solved by Newton‒Raphson method. In contrast to previous studies which consider intermolecular forces as short-range, the present study reveals more details of the features of adhesive contact with surface tension, in terms of jump instabilities, pull-off forces, pressure distribution within the contact area, etc. The transition of the pull-off force is not only consistent with previous studies, but also presents some new interesting characteristics in the current situation.

  15. Ride quality research techniques: Section on general techniques

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Information is gathered about the methods currently used for the study of ride quality in a variety of transportation modes by a variety of research organizations, including universities, Federal agencies, contracting firms, and private industries. Detailed descriptions of these techniques and their strengths and weaknesses, and identifying the organizations using such methods are presented. The specific efforts of the Group's participants, as well as a variety of feasible approaches not currently in use, are presented as methodological alternatives under the three basic factors which must be considered in ride quality studies: research techniques, research environments, and choice of subjects.

  16. Semantic e-Science in Space Physics - A Case Study

    NASA Astrophysics Data System (ADS)

    Narock, T.; Yoon, V.; Merka, J.; Szabo, A.

    2009-05-01

    Several search and retrieval systems for space physics data are currently under development in NASA's heliophysics data environment. We present a case study of two such systems, and describe our efforts in implementing an ontology to aid in data discovery. In doing so we highlight the various aspects of knowledge representation and show how they led to our ontology design, creation, and implementation. We discuss advantages that scientific reasoning allows, as well as difficulties encountered in current tools and standards. Finally, we present a space physics research project conducted with and without e-Science and contrast the two approaches.

  17. Study of charged hadron multiplicities in charged-current neutrino-lead interactions in the OPERA detector

    NASA Astrophysics Data System (ADS)

    Agafonova, N.; Aleksandrov, A.; Anokhina, A.; Aoki, S.; Ariga, A.; Ariga, T.; Bertolin, A.; Bodnarchuk, I.; Bozza, C.; Brugnera, R.; Buonaura, A.; Buontempo, S.; Chernyavskiy, M.; Chukanov, A.; Consiglio, L.; D'Ambrosio, N.; De Lellis, G.; De Serio, M.; del Amo Sanchez, P.; Di Crescenzo, A.; Di Ferdinando, D.; Di Marco, N.; Dmitrievski, S.; Dracos, M.; Duchesneau, D.; Dusini, S.; Dzhatdoev, T.; Ebert, J.; Ereditato, A.; Fini, R. A.; Fornari, F.; Fukuda, T.; Galati, G.; Garfagnini, A.; Gentile, V.; Goldberg, J.; Gornushkin, Y.; Gorbunov, S.; Grella, G.; Guler, A. M.; Gustavino, C.; Hagner, C.; Hara, T.; Hayakawa, T.; Hollnagel, A.; Hosseini, B.; Ishiguro, K.; Jakovcic, K.; Jollet, C.; Kamiscioglu, C.; Kamiscioglu, M.; Kim, S. H.; Kitagawa, N.; Klicek, B.; Kodama, K.; Komatsu, M.; Kose, U.; Kreslo, I.; Laudisio, F.; Lauria, A.; Ljubicic, A.; Longhin, A.; Loverre, P.; Malgin, A.; Malenica, M.; Mandrioli, G.; Matsuo, T.; Matveev, V.; Mauri, N.; Medinaceli, E.; Meregaglia, A.; Mikado, S.; Miyanishi, M.; Mizutani, F.; Monacelli, P.; Montesi, M. C.; Morishima, K.; Muciaccia, M. T.; Naganawa, N.; Naka, T.; Nakamura, M.; Nakano, T.; Niwa, K.; Okateva, N.; Ogawa, S.; Ozaki, K.; Paoloni, A.; Paparella, L.; Park, B. D.; Pasqualini, L.; Pastore, A.; Patrizii, L.; Pessard, H.; Podgrudkov, D.; Polukhina, N.; Pozzato, M.; Pupilli, F.; Roda, M.; Roganova, T.; Rokujo, H.; Rosa, G.; Ryazhskaya, O.; Sato, O.; Schembri, A.; Shakirianova, I.; Shchedrina, T.; Shibuya, H.; Shibayama, E.; Shiraishi, T.; Simone, S.; Sirignano, C.; Sirri, G.; Sotnikov, A.; Spinetti, M.; Stanco, L.; Starkov, N.; Stellacci, S. M.; Stipcevic, M.; Strolin, P.; Takahashi, S.; Tenti, M.; Terranova, F.; Tioukov, V.; Vasina, S.; Vilain, P.; Voevodina, E.; Votano, L.; Vuilleumier, J. L.; Wilquet, G.; Wonsak, B.; Yoon, C. S.

    2018-01-01

    The OPERA experiment was designed to search for ν _{μ } → ν _{τ } oscillations in appearance mode through the direct observation of tau neutrinos in the CNGS neutrino beam. In this paper, we report a study of the multiplicity of charged particles produced in charged-current neutrino interactions in lead. We present charged hadron average multiplicities, their dispersion and investigate the KNO scaling in different kinematical regions. The results are presented in detail in the form of tables that can be used in the validation of Monte Carlo generators of neutrino-lead interactions.

  18. Polarization observables and T-noninvariance in the weak charged current induced electron proton scattering

    NASA Astrophysics Data System (ADS)

    Fatima, A.; Sajjad Athar, M.; Singh, S. K.

    2018-06-01

    In this work, we have studied the total scattering cross section (σ, differential scattering cross section ( dσ/d Q2) as well as the longitudinal ( P_L(Ee,Q2)), perpendicular ( PP(Ee,Q2)), and transverse ( PT(Ee,Q2)) components of the polarization of the final hadron ( n, Λ and Σ0) produced in the electron proton scattering induced by the weak charged current. We have not assumed T-invariance which allows the transverse component of the hadron polarization perpendicular to the production plane to be non-zero. The numerical results are presented for all the above observables and their dependence on the axial vector form factor and the weak electric form factor are discussed. The present study enables the determination of the axial vector nucleon-hyperon transition form factors at high Q2 in the strangeness sector which can provide a test of the symmetries of the weak hadronic currents like T-invariance and SU(3) symmetry while assuming the hypothesis of conserved vector current and partial conservation of axial vector current.

  19. One ring to rule them all: storm time ring current and its influence on radiation belts, plasmasphere and global magnetosphere electrodynamics

    NASA Astrophysics Data System (ADS)

    Buzulukova, Natalia; Fok, Mei-Ching; Glocer, Alex; Moore, Thomas E.

    2013-04-01

    We report studies of the storm time ring current and its influence on the radiation belts, plasmasphere and global magnetospheric dynamics. The near-Earth space environment is described by multiscale physics that reflects a variety of processes and conditions that occur in magnetospheric plasma. For a successful description of such a plasma, a complex solution is needed which allows multiple physics domains to be described using multiple physical models. A key population of the inner magnetosphere is ring current plasma. Ring current dynamics affects magnetic and electric fields in the entire magnetosphere, the distribution of cold ionospheric plasma (plasmasphere), and radiation belts particles. To study electrodynamics of the inner magnetosphere, we present a MHD model (BATSRUS code) coupled with ionospheric solver for electric field and with ring current-radiation belt model (CIMI code). The model will be used as a tool to reveal details of coupling between different regions of the Earth's magnetosphere. A model validation will be also presented based on comparison with data from THEMIS, POLAR, GOES, and TWINS missions. INVITED TALK

  20. OVERVIEW OF VOLUNTARY STEWARDSHIP EFFORTS TO ADDRESS PHARMACEUTICAL DISPOSAL

    EPA Science Inventory

    This presentation will provide an overview of current federal regulatory guidance for pharmaceutical disposal, currently funded pilot programs for take-back pilot studies, and state programs. The EPA Office of Water's role is to protect our Nation's watersheds and drinking water ...

  1. Preliminary Upper Estimate of Peak Currents in Transcranial Magnetic Stimulation at Distant Locations from a TMS Coil

    PubMed Central

    Makarov, Sergey N.; Yanamadala, Janakinadh; Piazza, Matthew W.; Helderman, Alex M.; Thang, Niang S.; Burnham, Edward H.; Pascual-Leone, Alvaro

    2016-01-01

    Goals Transcranial magnetic stimulation (TMS) is increasingly used as a diagnostic and therapeutic tool for numerous neuropsychiatric disorders. The use of TMS might cause whole-body exposure to undesired induced currents in patients and TMS operators. The aim of the present study is to test and justify a simple analytical model known previously, which may be helpful as an upper estimate of eddy current density at a particular distant observation point for any body composition and any coil setup. Methods We compare the analytical solution with comprehensive adaptive mesh refinement-based FEM simulations of a detailed full-body human model, two coil types, five coil positions, about 100,000 observation points, and two distinct pulse rise times, thus providing a representative number of different data sets for comparison, while also using other numerical data. Results Our simulations reveal that, after a certain modification, the analytical model provides an upper estimate for the eddy current density at any location within the body. In particular, it overestimates the peak eddy currents at distant locations from a TMS coil by a factor of 10 on average. Conclusion The simple analytical model tested in the present study may be valuable as a rapid method to safely estimate levels of TMS currents at different locations within a human body. Significance At present, safe limits of general exposure to TMS electric and magnetic fields are an open subject, including fetal exposure for pregnant women. PMID:26685221

  2. Large dunes on the outer shelf off the Zambezi Delta, Mozambique: evidence for the existence of a Mozambique Current

    NASA Astrophysics Data System (ADS)

    Flemming, Burghard W.; Kudrass, Hermann-Rudolf

    2018-02-01

    The existence of a continuously flowing Mozambique Current, i.e. a western geostrophic boundary current flowing southwards along the shelf break of Mozambique, was until recently accepted by oceanographers studying ocean circulation in the south-western Indian Ocean. This concept was then cast into doubt based on long-term current measurements obtained from current-meter moorings deployed across the northern Mozambique Channel, which suggested that southward flow through the Mozambique Channel took place in the form of successive, southward migrating and counter-clockwise rotating eddies. Indeed, numerical modelling found that, if at all, strong currents on the outer shelf occurred for not more than 9 days per year. In the present study, the negation of the existence of a Mozambique Current is challenged by the discovery of a large (50 km long, 12 km wide) subaqueous dune field (with up to 10 m high dunes) on the outer shelf east of the modern Zambezi River delta at water depths between 50 and 100 m. Being interpreted as representing the current-modified, early Holocene Zambezi palaeo-delta, the dune field would have migrated southwards by at least 50 km from its former location since sea level recovered to its present-day position some 7 ka ago and after the former delta had been remoulded into a migrating dune field. Because a large dune field composed of actively migrating bedforms cannot be generated and maintained by currents restricted to a period of only 9 days per year, the validity of those earlier modelling results is questioned for the western margin of the flow field. Indeed, satellite images extracted from the Perpetual Ocean display of NASA, which show monthly time-integrated surface currents in the Mozambique Channel for the 5 month period from June-October 2006, support the proposition that strong flow on the outer Mozambican shelf occurs much more frequently than postulated by those modelling results. This is consistent with more recent modelling studies comparing the application of slippage and non-slippage approaches—they suggest that, when applying partial slippage, a western boundary current can exist simultaneously with the southward migrating eddies. Considering the evidence presented in this paper, it is concluded that a quasi-persistent, though seasonally variable Mozambique Current does exist.

  3. Relative importance of current and past landscape structure and local habitat conditions for plant species richness in dry grassland-like forest openings.

    PubMed

    Husáková, Iveta; Münzbergová, Zuzana

    2014-01-01

    In fragmented landscapes, plant species richness may depend not only on local habitat conditions but also on landscape structure. In addition, both present and past landscape structure may be important for species richness. There are, however, only a few studies that have investigated the relative importance of all of these factors. The aim of this study was to examine the effect of current and past landscape structures and habitat conditions on species richness at dry grassland-like forest openings in a forested landscape and to assess their relative importance for species richness. We analyzed information on past and present landscape structures using aerial photographs from 1938, 1973, 1988, 2000 and 2007. We calculated the area of each locality and its isolation in the present and in the past and the continuity of localities in GIS. At each locality, we recorded all vascular plant species (296 species in 110 forest openings) and information on abiotic conditions of the localities. We found that the current species richness of the forest openings was significantly determined by local habitat conditions as well as by landscape structure in the present and in the past. The highest species richness was observed on larger and more heterogeneous localities with rocks and shallow soils, which were already large and well connected to other localities in 1938. The changes in the landscape structure in the past can thus have strong effects on current species richness. Future studies attempting to understand determinants of species diversity in fragmented landscapes should also include data on past landscape structure, as it may in fact be more important than the present structure.

  4. Covariates of Current Cigarette Smoking among Secondary School Students in Budapest, Hungary, 1999

    ERIC Educational Resources Information Center

    Easton, Alyssa; Kiss, Eva

    2005-01-01

    To date, few studies have examined the relationship between health behavior risk factors and cigarette smoking in Hungary. From 1995 to 1999, the prevalence of current smoking increased from 35.9 to 46.0% among secondary students in Budapest, Hungary. The objective of the present study was to examine the association between smoking and other…

  5. A Laboratory Activity on the Eddy Current Brake

    ERIC Educational Resources Information Center

    Molina-Bolivar, J. A.; Abella-Palacios, A. J.

    2012-01-01

    The aim of this paper is to introduce a simple and low-cost experimental setup that can be used to study the eddy current brake, which considers the motion of a sliding magnet on an inclined conducting plane in terms of basic physical principles. We present a set of quantitative experiments performed to study the influence of the geometrical and…

  6. A study of current world telecommunications and a projection of the future

    NASA Astrophysics Data System (ADS)

    Karageorgis, Costas

    1992-09-01

    Telecommunications today are important factors in economic and social progress. The last decades of the 20th century and the early years of the 21st have been characterized as the Information Age. Telecommunications, the movement of information through distances, is absolutely critical to the economic and military survival of nations. This thesis is an attempt to predict the future of telecommunications, by studying and analyzing the past and present. First it examines the meaning of telecommunications today and some basics of information transmission. The current status of telecommunications is then presented, by examining the regional profiles as they are divided by the International Telecommunications Union. A number of statistical studies are given, which present a thorough picture of current world telecommunications. In an effort to predict future industry trends, the competition among the three largest telecommunications markets, U.S.A., Japan and the European Community, is also considered by looking at their present telecommunications industry, the efforts they make to improve their technology, and their plans for future investment. Finally, some major technological trends including BISDN, the use of fiber technology in the communications loop, and the use of solitons are examined. The new Metropolitan Area Network Protocol, FDDI-2 is also reviewed.

  7. Concise Review: Endothelial Progenitor Cells in Regenerative Medicine: Applications and Challenges

    PubMed Central

    Chong, Mark Seow Khoon; Ng, Wei Kai

    2016-01-01

    Endothelial progenitor cells (EPCs) are currently being studied as candidate cell sources for revascularization strategies. Significant advances have been made in understanding the biology of EPCs, and preclinical studies have demonstrated the vasculogenic, angiogenic, and beneficial paracrine effects of transplanted EPCs in the treatment of ischemic diseases. Despite these promising results, widespread clinical acceptance of EPCs for clinical therapies remains hampered by several challenges. The present study provides a concise summary of the different EPC populations being studied for ischemic therapies and their known roles in the healing of ischemic tissues. The challenges and issues surrounding the use of EPCs and the current strategies being developed to improve the harvest efficiency and functionality of EPCs for application in regenerative medicine are discussed. Significance Endothelial progenitor cells (EPCs) have immense clinical value for cardiovascular therapies. The present study provides a concise description of the EPC subpopulations being evaluated for clinical applications. The current major lines of investigation involving preclinical and clinical evaluations of EPCs are discussed, and significant gaps limiting the translation of EPCs are highlighted. The present report could be useful for clinicians and clinical researchers with interests in ischemic therapy and for basic scientists working in the related fields of tissue engineering and regenerative medicine. PMID:26956207

  8. A Collection of Papers on Self-Study and Institutional Improvement, 1996.

    ERIC Educational Resources Information Center

    Van Kollenburg, Susan E., Ed.

    This collection presents 68 papers or summaries presented at a 1996 conference on self-study and institutional improvement for institutions of higher education. Papers are grouped in the following 10 chapters (with sample topics in parentheses): (1) "Integrity and Accreditation: Current Issues" (intercollegiate athletics, nontraditional students,…

  9. Comparison between Phase-Shift Full-Bridge Converters with Noncoupled and Coupled Current-Doubler Rectifier

    PubMed Central

    Tsai, Cheng-Tao; Tseng, Sheng-Yu

    2013-01-01

    This paper presents comparison between phase-shift full-bridge converters with noncoupled and coupled current-doubler rectifier. In high current capability and high step-down voltage conversion, a phase-shift full-bridge converter with a conventional current-doubler rectifier has the common limitations of extremely low duty ratio and high component stresses. To overcome these limitations, a phase-shift full-bridge converter with a noncoupled current-doubler rectifier (NCDR) or a coupled current-doubler rectifier (CCDR) is, respectively, proposed and implemented. In this study, performance analysis and efficiency obtained from a 500 W phase-shift full-bridge converter with two improved current-doubler rectifiers are presented and compared. From their prototypes, experimental results have verified that the phase-shift full-bridge converter with NCDR has optimal duty ratio, lower component stresses, and output current ripple. In component count and efficiency comparison, CCDR has fewer components and higher efficiency at full load condition. For small size and high efficiency requirements, CCDR is relatively suitable for high step-down voltage and high efficiency applications. PMID:24381521

  10. Comparison between phase-shift full-bridge converters with noncoupled and coupled current-doubler rectifier.

    PubMed

    Tsai, Cheng-Tao; Su, Jye-Chau; Tseng, Sheng-Yu

    2013-01-01

    This paper presents comparison between phase-shift full-bridge converters with noncoupled and coupled current-doubler rectifier. In high current capability and high step-down voltage conversion, a phase-shift full-bridge converter with a conventional current-doubler rectifier has the common limitations of extremely low duty ratio and high component stresses. To overcome these limitations, a phase-shift full-bridge converter with a noncoupled current-doubler rectifier (NCDR) or a coupled current-doubler rectifier (CCDR) is, respectively, proposed and implemented. In this study, performance analysis and efficiency obtained from a 500 W phase-shift full-bridge converter with two improved current-doubler rectifiers are presented and compared. From their prototypes, experimental results have verified that the phase-shift full-bridge converter with NCDR has optimal duty ratio, lower component stresses, and output current ripple. In component count and efficiency comparison, CCDR has fewer components and higher efficiency at full load condition. For small size and high efficiency requirements, CCDR is relatively suitable for high step-down voltage and high efficiency applications.

  11. In vitro and in vivo comparisons of constant resistance AC iontophoresis and DC iontophoresis.

    PubMed

    Li, S Kevin; Higuchi, William I; Zhu, Honggang; Kern, Steven E; Miller, David J; Hastings, Matthew S

    2003-09-04

    A previous in vitro constant electrical resistance alternating current (AC) iontophoresis study with human epidermal membrane (HEM) and a model neutral permeant has shown less inter- and intra-sample variability in iontophoretic transport relative to conventional constant direct current (DC) iontophoresis. The objectives of the present study were to address the following questions. (1) Can the skin electrical resistance be maintained at a constant level by AC in humans in vivo? (2) Are the in vitro data with HEM representative of those in vivo? (3) Does constant skin resistance AC iontophoresis have less inter- and intra-sample variability than conventional constant current DC iontophoresis in vivo? (4) What are the electrical and the barrier properties of skin during iontophoresis in vivo? In the present study, in vitro HEM experiments were carried out with the constant resistance AC and the conventional constant current DC methods using mannitol and glucose as the neutral model permeants. In vivo human experiments were performed using glucose as the permeant with a constant skin resistance AC only protocol and two conventional constant current DC methods (continuous constant current DC and constant current DC with its polarity alternated every 10 min with a 3:7 on:off duty cycle). Constant current DC iontophoresis was conducted with commercial constant current DC devices, and constant resistance AC iontophoresis was carried out by reducing and maintaining the skin resistance at a constant target value with AC supplied from a function generator. This study shows that (1) skin electrical resistance can be maintained at a constant level during AC iontophoresis in vivo; (2) HEM in vitro and human skin in vivo demonstrate similar electrical and barrier properties, and these properties are consistent with our previous findings; (3) there is general qualitative and semi-quantitative agreement between the HEM data in vitro and human skin data in vivo; and (4) constant skin resistance AC iontophoresis generally provides less inter- and intra-subject variability than conventional constant current DC.

  12. Non-Use of Motor Vehicle Safety Belts as an Issue in Civil Litigation

    DOT National Transportation Integrated Search

    1983-08-01

    The current and potential role of the "safety belt defense" in civil litigation is studied. The paper presents an overview of the safety belt defense, including an evaluation of current precedent. Based on interviews with leading motor vehicle civil ...

  13. Bed bug detection: Current technologies and future directions

    USDA-ARS?s Scientific Manuscript database

    This study evaluates current technologies used to detect bed bug infestations, and presents new information regarding the underlying chemical basis of canines scent detection. The manuscript also reports new and future devices that may play a part in bed bug detection in the future....

  14. Formation of a spark discharge in an inhomogeneous electric field with current limitation by a large ballast Resistance

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

    Baldanov, B. B., E-mail: baibat@mail.ru

    2016-01-15

    Results of studies of a spark discharge initiated in argon in a point–plane electrode gap with limitation of the discharge current by a large ballast resistance are presented. It is shown that the current flowing through the plasma channel of such a low-current spark has the form of periodic pulses. It is experimentally demonstrated that, when a low-current spark transforms into a constricted glow discharge, current pulses disappear, the spatial structure of the cathode glow changes abruptly, and a brightly glowing positive plasma column forms in the gap.

  15. Interdisciplinary Approaches--Past and Present--to Foreign Language and Literature Studies.

    ERIC Educational Resources Information Center

    Jaffe, Samuel

    This paper discusses some past and present interdisciplinary approaches to foreign language and literature (FLL) studies. It is argued that the current unpopularity of FLL studies in the United States is the consequence of falling away from viable traditions of scholarship and teaching in this area. A model for reform which reawaken interest in…

  16. Contextual Factors in the Use of the Present Perfect

    ERIC Educational Resources Information Center

    Moy, Raymond H.

    1977-01-01

    In this study the inadequacies of rules governing the present perfect in isolated sentences are discussed and then two contextual factors thought to be connected with current relevance and the use of the present perfect are described. These factors are experimentally shown to influence use of the present perfect significantly. (CHK)

  17. Harmonic and reactive behavior of the quasiparticle tunnel current in SIS junctions

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

    Rashid, H., E-mail: hawal@chalmers.se; Desmaris, V.; Pavolotsky, A.

    In this paper, we show theoretically and experimentally that the reactive quasiparticle tunnel current of the superconductor tunnel junction could be directly measured at specific bias voltages for the higher harmonics of the quasiparticle tunnel current. We used the theory of quasiparticle tunneling to study the higher harmonics of the quasiparticle tunnel current in superconducting tunnel junction in the presence of rf irradiation. The impact of the reactive current on the harmonic behavior of the quasiparticle tunnel current was carefully studied by implementing a practical model with four parameters to model the dc I-V characteristics of the superconducting tunnel junction.more » The measured reactive current at the specific bias voltage is in good agreement with our theoretically calculated reactive current through the Kramers-Kronig transform. This study also shows that there is an excellent correspondence between the behavior of the predicted higher harmonics using the previously established theory of quasiparticle tunnel current in superconducting tunnel junctions by J.R. Tucker and M.J. Feldman and the measurements presented in this paper.« less

  18. Blocked versus randomized presentation modes differentially modulate feedback-related negativity and P3b amplitudes

    PubMed Central

    Pfabigan, Daniela M.; Zeiler, Michael; Lamm, Claus; Sailer, Uta

    2014-01-01

    Objective Electrophysiological studies on feedback processing typically use a wide range of feedback stimuli which might not always be comparable. The current study investigated whether two indicators of feedback processing – feedback-related negativity (FRN) and P3b – differ for feedback stimuli with explicit (facial expressions) or assigned valence information (symbols). In addition, we assessed whether presenting feedback in either a trial-by-trial or a block-wise fashion affected these ERPs. Methods EEG was recorded in three experiments while participants performed a time estimation task and received two different types of performance feedback. Results Only P3b amplitudes varied consistently in response to feedback type for both presentation types. Moreover, the blocked feedback type presentation yielded more distinct FRN peaks, higher effect sizes, and a significant relation between FRN amplitudes and behavioral task performance measures. Conclusion Both stimulus type and presentation mode may provoke systematic changes in feedback-related ERPs. The current findings point at important potential confounds that need to be controlled for when designing FRN or P3b studies. Significance Studies investigating P3b amplitudes using mixed types of stimuli have to be interpreted with caution. Furthermore, we suggest implementing a blocked presentation format when presenting different feedback types within the same experiment. PMID:24144779

  19. The Rogowski Coil Sensor in High Current Application: A Review

    NASA Astrophysics Data System (ADS)

    Nazmy Nanyan, Ayob; Isa, Muzamir; Hamid, Haziah Abdul; Nur Khairul Hafizi Rohani, Mohamad; Ismail, Baharuddin

    2018-03-01

    Rogowski coil is used for measuring the alternating current (AC) and high-speed current pulses. However, the technology makes the Rogowski coil (RC) come out with more improvement, modification and until today it’s still being studied for the new application. The Rogowski coil has a few advantages compared to the high frequency current transformer (HFCT). A brief review on the basic theory and the application of Rogowski coil as a current sensor measurement that been done by previous researchers are presented and discussed in this paper. Additionally, the review also focused on the capability of Rogowski coil for high current sensor measurement and their application for fault detection, over voltage current sensor, lightning current sensor and high impulse current detection. The experimental set up, techniques and measurement parameters in models also been discussed. Finally, a brief review on the performance analysis of current sensor measurement of Rogowski coil likes sensitivity, the maximum and current detection which could be used as a guideline to another researcher in order to develop an advanced RC as high current sensor in future is presented. This review reveal that the RC has a very good performance in high current sensor detection in term of sensitivity which is up to a few nanosecond, higher bandwidth, excellent in detection of high fault and also could measuring lightning current up to 400kA and has many advantages compare to conventional current transformer(CT).

  20. An electric current associated with gravity sensing in maize roots

    NASA Technical Reports Server (NTRS)

    Bjorkman, T.; Leopold, A. C.

    1987-01-01

    The study of gravisensing would be greatly enhanced if physiological events associated with gravity sensing could be detected separately from subsequent growth processes. This report presents a means to discriminate sensing from the growth processes. By using a vibrating probe, we have found an electric current generated by the gravity sensing region of the root cap of maize (Zea mays cv Merit) in response to gravistimulation. On the upper surface of the root cap, the change from the endogenous current has a density of 0.55 microampere per square centimeter away from gravity. The onset of the current shift has a characteristic of lag of three to four minutes after gravistimulation, which corresponds to the presentation time for gravity sensing in this tissue. A description of the current provides some information about the sensing mechanism, as well as being a valuable means to detect gravity sensing independently of differential growth.

  1. A Mathematical Model of Neonatal Rat Atrial Monolayers with Constitutively Active Acetylcholine-Mediated K+ Current

    PubMed Central

    Majumder, Rupamanjari; Jangsangthong, Wanchana; Feola, Iolanda; Ypey, Dirk L.; Pijnappels, Daniël A.; Panfilov, Alexander V.

    2016-01-01

    Atrial fibrillation (AF) is the most frequent form of arrhythmia occurring in the industrialized world. Because of its complex nature, each identified form of AF requires specialized treatment. Thus, an in-depth understanding of the bases of these arrhythmias is essential for therapeutic development. A variety of experimental studies aimed at understanding the mechanisms of AF are performed using primary cultures of neonatal rat atrial cardiomyocytes (NRAMs). Previously, we have shown that the distinct advantage of NRAM cultures is that they allow standardized, systematic, robust re-entry induction in the presence of a constitutively-active acetylcholine-mediated K+ current (IKACh-c). Experimental studies dedicated to mechanistic explorations of AF, using these cultures, often use computer models for detailed electrophysiological investigations. However, currently, no mathematical model for NRAMs is available. Therefore, in the present study we propose the first model for the action potential (AP) of a NRAM with constitutively-active acetylcholine-mediated K+ current (IKACh-c). The descriptions of the ionic currents were based on patch-clamp data obtained from neonatal rats. Our monolayer model closely mimics the action potential duration (APD) restitution and conduction velocity (CV) restitution curves presented in our previous in vitro studies. In addition, the model reproduces the experimentally observed dynamics of spiral wave rotation, in the absence and in the presence of drug interventions, and in the presence of localized myofibroblast heterogeneities. PMID:27332890

  2. CHI Research on NSTX-U

    NASA Astrophysics Data System (ADS)

    Lay, W.-S.; Raman, R.; Jarboe, T. R.; Nelson, B. A.; Mueller, D.; Ebrahimi, F.; Ono, M.; Jardin, S. C.; Taylor, G.

    2017-10-01

    At present about 20% of the total plasma current required for sustained operation has been generated by transient CHI. The present understanding suggests that it may be possible to generate all of the needed current in a ST / tokamak using transient CHI. In such a scenario, one could transition directly from a CHI produced plasma to a non-inductively sustained plasma, without the difficult intermediate step that involves non-inductive current ramp-up. STs based on this new configuration would take advantage of evolving developments in high-temperature superconductor technology to develop a simpler design ST that relies primarily on CHI for plasma current generation. Motivated by the very good results from NSTX and HIT-II, we are examining the potential application of transient CHI for reactor configurations through these studies. (1) Study of the maximum levels of start-up currents that could be generated on NSTX-U, (2) application of a single biased electrode configuration on QUEST to protect the insulator from neutron damage in a CHI reactor installation, and (3) QUEST-like, but a double biased electrode configuration for PEGASUS and NSTX-U. Results from these on-going studies will be described. This work is supported by U.S. DOE Contracts: DE-AC02-09CH11466, DE-FG02-99ER54519 AM08, and DE-SC0006757.

  3. Current and anticipated uses of the CATHARE code at EDF and FRAMATOME

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

    Gandrille, J.L.; Vacher, J.L.; Poizat, F.

    1997-07-01

    This paper presents current industrial applications of the CATHARE code in the fields of Safety Studies and Simulators where the code is intensively used by FRAMATOME, EDF and CEA, the development partners of CATHARE. Future needs in these fields are also recapitulated.

  4. [Anorexia nervosa and bulimia nervosa. Psychological considerations for its treatment].

    PubMed

    Barriguete Meléndez, J Armando; Rojo, Luis; Emmelhainz, Marisa

    2004-11-01

    It is presented the current perspectives in the study and treatment of the eating disorders, in specific: anorexia nervosa and bulimia nervosa, epidemiology, and the interface among the different medical specialties, nutrition and sciences of the behavior, the diagnostic approaches, instruments and current therapeutic models.

  5. Contemporary Inventional Theory: An Aristotelian Model.

    ERIC Educational Resources Information Center

    Skopec, Eric W.

    Contemporary rhetoricians are concerned with the re-examination of classical doctrines in the hope of finding solutions to current problems. In this study, the author presents a methodological perspective consistent with current interests, by re-examining the assumptions that underlie each classical precept. He outlines an inventional system based…

  6. Inclusive Education in Georgia: Current Trends and Challenges

    ERIC Educational Resources Information Center

    Tchintcharauli, Tinatin; Javakhishvili, Nino

    2017-01-01

    This article presents the first comprehensive study of the Georgian inclusive education system launched nationwide in 2006. An internationally recognised tool, the "Pathway to Inclusion--Barometer of Inclusive Education", was applied within the country to highlight the current position of inclusive education in Georgia. The collected…

  7. GOALS AND CURRENT RESEARCH OF EPA'S STREAM RESTORATION RESEARCH PROGRAM

    EPA Science Inventory

    The US EPA is involved in ongoing research on stream and riparian restoration. This presentation is designed to discuss current EPA research efforts, identify key issues in the science and practice of stream restoration, and to help frame a future National Research Council study...

  8. Current drive by helicon waves

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

    Paul, Manash Kumar; Bora, Dhiraj; ITER Organization, Cadarache Centre-building 519, 131008 St. Paul-Lez-Durance

    2009-01-01

    Helicity in the dynamo field components of helicon wave is examined during the novel study of wave induced helicity current drive. Strong poloidal asymmetry in the wave magnetic field components is observed during helicon discharges formed in a toroidal vacuum chamber of small aspect ratio. High frequency regime is chosen to increase the phase velocity of helicon waves which in turn minimizes the resonant wave-particle interactions and enhances the contribution of the nonresonant current drive mechanisms. Owing to the strong poloidal asymmetry in the wave magnetic field structures, plasma current is driven mostly by the dynamo-electric-field, which arise due tomore » the wave helicity injection by helicon waves. Small, yet finite contribution from the suppressed wave-particle resonance cannot be ruled out in the operational regime examined. A brief discussion on the parametric dependence of plasma current along with numerical estimations of nonresonant components is presented. A close agreement between the numerical estimation and measured plasma current magnitude is obtained during the present investigation.« less

  9. Cargo Logistics Airlift Systems Study (CLASS). Volume 1: Analysis of current air cargo system

    NASA Technical Reports Server (NTRS)

    Burby, R. J.; Kuhlman, W. H.

    1978-01-01

    The material presented in this volume is classified into the following sections; (1) analysis of current routes; (2) air eligibility criteria; (3) current direct support infrastructure; (4) comparative mode analysis; (5) political and economic factors; and (6) future potential market areas. An effort was made to keep the observations and findings relating to the current systems as objective as possible in order not to bias the analysis of future air cargo operations reported in Volume 3 of the CLASS final report.

  10. Wind turbines: current status, obstacles, trends and technologies

    NASA Astrophysics Data System (ADS)

    Konstantinidis, E. I.; Botsaris, P. N.

    2016-11-01

    The last decade the installation of wind farms around the world is spreading rapidly and wind energy has become a significant factor for promoting sustainable development. The scope of the present study is to indicate the present status of global wind power expansion as well as the current state of the art in the field of wind turbine technology. The RAM (reliability/availability/maintenance) section is also examined and the Levelized Cost of Energy for onshore/ offshore electricity production is presented. Negative consequences that go with the rapid expansion of wind power like accidents, environmental effects, etc. are highlighted. Especially visual impact to the landscape and noise pollution are some factors that provoke social reactions. Moreover, the complicated and long permitted process of a wind power plant, the high capital cost of the investment and the grid instability due to the intermittent nature of wind, are also significant obstacles in the development of the wind energy production. The current trends in the field of research and development of onshore and offshore wind power production are analyzed. Finally the present study is trying to achieve an estimation of where the wind industry targets for the years to come.

  11. Study the Current and Optimal Status of Teaching Environment at High Schools with Emphasis on Curriculum Experts' and Teachers' Viewpoints

    ERIC Educational Resources Information Center

    Parishani, Neda; Jafari, Seyed Ebrahim Mir Shah; Sharifian, Fereydoon; Farhadian, Mehrdad

    2016-01-01

    The purpose of present research was to study the current and optimal status of teaching environment at high schools in Iran with emphasis on curriculum experts and teachers' viewpoints. Research method was mixed method. In the qualitative part, experts' viewpoints were gathered through a semi-structured interview. In the quantitative part, 258…

  12. Inflammation-induced increase in nicotinic acetylcholine receptor current in cutaneous nociceptive DRG neurons from the adult rat.

    PubMed

    Zhang, X-L; Albers, K M; Gold, M S

    2015-01-22

    The goals of the present study were to determine (1) the properties of the nicotinic acetylcholine receptor (nAChR) currents in rat cutaneous dorsal root ganglion (DRG) neurons; (2) the impact of nAChR activation on the excitability of cutaneous DRG neurons; and (3) the impact of inflammation on the density and distribution of nAChR currents among cutaneous DRG neurons. Whole-cell patch-clamp techniques were used to study retrogradely labeled DRG neurons from naïve and complete Freund's adjuvant inflamed rats. Nicotine-evoked currents were detectable in ∼70% of the cutaneous DRG neurons, where only one of two current types, fast or slow currents based on rates of activation and inactivation, was present in each neuron. The biophysical and pharmacological properties of the fast current were consistent with nAChRs containing an α7 subunit while those of the slow current were consistent with nAChRs containing α3/β4 subunits. The majority of small diameter neurons with fast current were IB4- while the majority of small diameter neurons with slow current were IB4+. Preincubation with nicotine (1 μM) produced a transient (1 min) depolarization and increase in the excitability of neurons with fast current and a decrease in the amplitude of capsaicin-evoked current in neurons with slow current. Inflammation increased the current density of both slow and fast currents in small diameter neurons and increased the percentage of neurons with the fast current. With the relatively selective distribution of nAChR currents in putative nociceptive cutaneous DRG neurons, our results suggest that the role of these receptors in inflammatory hyperalgesia is likely to be complex and dependent on the concentration and timing of acetylcholine release in the periphery. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

  13. Operationally Efficient Propulsion System Study (OEPSS) data book. Volume 2: Ground operations problems

    NASA Technical Reports Server (NTRS)

    Waldrop, Glen S.

    1990-01-01

    Operations problems and cost drivers were identified for current propulsion systems and design and technology approaches were identified to increase the operational efficiency and to reduce operations costs for future propulsion systems. To provide readily usable data for the ALS program, the results of the OEPSS study were organized into a series of OEPSS Data Books. This volume presents a detailed description of 25 major problems encountered during launch processing of current expendable and reusable launch vehicles. A concise description of each problem and its operational impact on launch processing is presented, along with potential solutions and technology recommendation.

  14. [Basics of Ear Surgery].

    PubMed

    Lailach, S; Zahnert, T

    2016-12-01

    The present article about the basics of ear surgery is a short overview of current indications, the required diagnostics and surgical procedures of common otologic diseases. In addition to plastic and reconstructive surgery of the auricle, principles of surgery of the external auditory canal, basics of middle ear surgery and the tumor surgery of the temporal bone are shown. Additionally, aspects of the surgical hearing rehabilitation (excluding implantable hearing systems) are presented considering current study results. Georg Thieme Verlag KG Stuttgart · New York.

  15. Muon neutrino CCQE at MINERvA

    DOE PAGES

    Betancourt, M.

    2016-12-13

    A precise understanding of quasi-elastic interactions is crucial to measure neutrino oscillations. The MINERvA experiment is currently working on different analyses of muon neutrino charged current quasi-elastic interactions. Here, we present updates to the previous quasi-elastic measurement, using a new flux, and we present the status of several analyses in progress; including double differential cross sections, a study of final state interactions using a sample with muon and a proton and the status of the CCQE analysis in the medium energy neutrino beam.

  16. Presenters at NASP 2013-2016: Where Are the Practitioners?

    ERIC Educational Resources Information Center

    Aspiranti, Kathleen B.; Jackson, Carrie

    2018-01-01

    Although one of the main functions of school psychology research is to inform practice, there remains a large research-to-practice gap. Both practitioners and scholars are crucial in ensuring that research within the field is comprehensive and well represented. In the current study, presenter, contributor, and presenter affiliation demographics…

  17. Special Study Institute for Teachers of Deaf-Blind Multihandicapped Children.

    ERIC Educational Resources Information Center

    Rouin, Carole

    Presented are the proceedings of the 1974 Special Study Institute for Teachers of Deaf-Blind Multihandicapped Children designed to give teachers an overview of current activities in the southwestern region of the United States. Presentations are divided into four sections--planning, services to parents and professionals, services to deaf-blind…

  18. Current Literature on Venereal Disease, 1972. Number Three. Abstracts and Bibliography.

    ERIC Educational Resources Information Center

    Lea, Mildred V., Ed.

    Presented are abstracts of documents and research pertaining to the clinical description, laboratory diagnosis, management, and therapy of syphilis and gonorrhea. Abstracted case studies of other minor venereal and related diseases are also included, as are bibliographies on current research and evaluation, public health methods, and behavioral…

  19. Current Literature on Venereal Disease, 1972. Number Two. Abstracts and Bibliography.

    ERIC Educational Resources Information Center

    Lea, Mildred V., Ed.

    Presented are abstracts of documents and research pertaining to the clinical description, laboratory diagnosis, management, and therapy of syphilis and gonorrhea. Abstracted case studies of other minor venereal and related diseases are also included, as are bibliographies on current research and evaluation, public health methods, and behavioral…

  20. Current Literature on Venereal Disease, 1972. Number One. Abstracts and Bibliography.

    ERIC Educational Resources Information Center

    Lea, Mildred V., Ed.

    Presented are abstracts of documents and research pertaining to the clinical description, laboratory diagnosis, management, and therapy of syphilis and gonorrhea. Abstracted case studies of other minor venereal and related diseases are also included, as are bibliographies on current research and evaluation, public health methods, and behavioral…

  1. Reflection of Constructivist Theories in Current Educational Practice

    ERIC Educational Resources Information Center

    Juvova, Alena; Chudy, Stefan; Neumeister, Pavel; Plischke, Jitka; Kvintova, Jana

    2015-01-01

    In this overview study, we would like to present the basic constructivist approaches that have affected or influenced the current concept of education. The teacher-student interaction is reflected by personality, psychological traits, attitudes and cultural capital of the participants of the educational process as well as the teacher's effort to…

  2. Learning from Fellow Engineering Students Who Have Current Professional Experience

    ERIC Educational Resources Information Center

    Davies, John W.; Rutherford, Ursula

    2012-01-01

    This paper presents an investigation of how experience-led content in an engineering degree can be strengthened by creating opportunities for engineering students to benefit from the knowledge, skills and resources of students with current professional experience. Students who study civil engineering part-time at Coventry University (while also…

  3. Assessing the bioaccumulation potential of ionizable organic compounds: Current knowledge and research priorities

    EPA Science Inventory

    The objective of the present study is to review current knowledge regarding the bioaccumulation potential of IOCs, with a focus on the availability of empirical data for fish. Aspects of the bioaccumulation potential of IOCs in fish that can be characterized relatively well inclu...

  4. Self-Paced Physics, Segments 28-31.

    ERIC Educational Resources Information Center

    New York Inst. of Tech., Old Westbury.

    Four study segments of the Self-Paced Physics Course materials are presented in this sixth problems and solutions book used as a part of student course work. The subject matter is related to electric currents, current densities, resistances, Ohm's law, voltages, Joule heating, electromotive forces, single loop circuits, series and parallel…

  5. Experimental study on the 300W class planar type solid oxide fuel cell stack: Investigation for appropriate fuel provision control and the transient capability of the cell performance

    NASA Astrophysics Data System (ADS)

    Komatsu, Y.; Brus, G.; Kimijima, S.; Szmyd, J. S.

    2012-11-01

    The present paper reports the experimental study on the dynamic behavior of a solid oxide fuel cell (SOFC). The cell stack consists of planar type cells with standard power output 300W. A Major subject of the present study is characterization of the transient response to the electric current change, assuming load-following operation. The present studies particularly focus on fuel provision control to the load change. Optimized fuel provision improves power generation efficiency. However, the capability of SOFC must be restricted by a few operative parameters. Fuel utilization factor, which is defined as the ratio of the consumed fuel to the supplied fuel is adopted for a reference in the control scheme. The fuel flow rate was regulated to keep the fuel utilization at 50%, 60% and 70% during the current ramping. Lower voltage was observed with the higher fuel utilization, but achieved efficiency was higher. The appropriate mass flow control is required not to violate the voltage transient behavior. Appropriate fuel flow manipulation can contribute to moderate the overshoot on the voltage that may appear to the current change. The overshoot on the voltage response resulted from the gradual temperature behavior in the SOFC stack module.

  6. Currents Induced by Injected Charge in Junction Detectors

    PubMed Central

    Gaubas, Eugenijus; Ceponis, Tomas; Kalesinskas, Vidas

    2013-01-01

    The problem of drifting charge-induced currents is considered in order to predict the pulsed operational characteristics in photo- and particle-detectors with a junction controlled active area. The direct analysis of the field changes induced by drifting charge in the abrupt junction devices with a plane-parallel geometry of finite area electrodes is presented. The problem is solved using the one-dimensional approach. The models of the formation of the induced pulsed currents have been analyzed for the regimes of partial and full depletion. The obtained solutions for the current density contain expressions of a velocity field dependence on the applied voltage, location of the injected surface charge domain and carrier capture parameters. The drift component of this current coincides with Ramo's expression. It has been illustrated, that the synchronous action of carrier drift, trapping, generation and diffusion can lead to a vast variety of possible current pulse waveforms. Experimental illustrations of the current pulse variations determined by either the rather small or large carrier density within the photo-injected charge domain are presented, based on a study of Si detectors. PMID:24036586

  7. Leading-edge vortex research: Some nonplanar concepts and current challenges

    NASA Technical Reports Server (NTRS)

    Campbell, J. F.; Osborn, R. F.

    1986-01-01

    Some background information is provided for the Vortex Flow Aerodynamics Conference and that current slender wing airplanes do not use variable leading edge geometry to improve transonic drag polar is shown. Highlights of some of the initial studies combining wing camber, or flaps, with vortex flow are presented. Current vortex flap studies were reviewed to show that there is a large subsonic data base and that transonic and supersonic generic studies have begun. There is a need for validated flow field solvers to calculate vortex/shock interactions at transonic and supersonic speeds. Many important research opportunities exist for fundamental vortex flow investigations and for designing advanced fighter concepts.

  8. Preliminary results from the hydrodynamic element of the 1994 entrapment zone study

    USGS Publications Warehouse

    Burau, J.R.; Stacey, M.; Gartner, J.W.

    1995-01-01

    This article discusses preliminary results from analyses of USGS hydrodynamic data collected as part of the 1994 Interagency Ecological Program entrapment zone study. The USGS took part in three 30-hour cruises and deployed instruments for measuring currents and salinity from April to June. This article primarily focuses on the analysis of data from five Acoustic Doppler Current ProUers (ADCPs) deployed in Carquinez Strait, Suisun Bay, and the Western Delta. From these analyses a revised conceptual model of the hydrodynamics of the entrapment/null zone has evolved. The ideas discussed in this newsletter article are essentially working hypotheses, which are presented here to stimulate discussion and further analyses. In this article we discuss the currently-held conceptual model of entrapment and present data that are inconsistent with this conceptual model. Finally, we suggest a revised conceptual model that is consistent with all of the hydrodynamic data collected to date and describe how the 1995 study incorporates our revised conceptual model into its design.

  9. Toxoplasma gondii Recombinant Antigens as Tools for Serodiagnosis of Human Toxoplasmosis: Current Status of Studies

    PubMed Central

    2013-01-01

    Toxoplasma gondii is a parasitic protozoan which is the cause of toxoplasmosis. Although human toxoplasmosis in healthy adults is usually asymptomatic, serious disease can occur in the case of congenital infections and immunocompromised individuals. Furthermore, despite the exact recognition of its etiology, it still presents a diagnostic problem. Diagnosis of toxoplasmosis is mainly based on the results of serological tests detecting anti-T. gondii-specific antibodies in the patient's serum sample. The specificities and sensitivities of serology tests depend mostly on the diagnostic antigen(s) used. Most of the commercial serological kits currently available are based on Toxoplasma lysate antigens (TLAs). In recent years, many studies showed that recombinant antigenic proteins of T. gondii may be an alternative source of antigens which are very useful for the serodiagnosis of toxoplasmosis. This article presents a review of current studies on the application and usefulness of different T. gondii recombinant antigens in serological tests for the diagnosis of human toxoplasmosis. PMID:23784855

  10. Nuclear Neutrino Spectra in Late Stellar Evolution

    NASA Astrophysics Data System (ADS)

    Misch, G. Wendell; Sun, Yang; Fuller, George

    2018-05-01

    Neutrinos are the principle carriers of energy in massive stars, beginning from core carbon burning and continuing through core collapse and after the core bounce. In fact, it may be possible to detect neutrinos from nearby pre-supernova stars. Therefore, it is of great interest to understand the neutrino energy spectra from these stars. Leading up to core collapse, beginning around core silicon burning, nuclei become dominant producers of neutrinos, particularly at high neutrino energy, so a systematic study of nuclear neutrino spectra is desirable. We have done such a study, and we present our sd-shell model calculations of nuclear neutrino energy spectra for nuclei in the mass number range A = 21 - 35. Our study includes neutrinos produced by charged lepton capture, charged lepton emission, and neutral current nuclear deexcitation. Previous authors have tabulated the rates of charged current nuclear weak interactions in astrophysical conditions, but the present work expands on this not only by providing neutrino energy spectra, but also by including the heretofore untabulated neutral current de-excitation neutrino pairs.

  11. On-line Monitoring Device for High-voltage Switch Cabinet Partial Discharge Based on Pulse Current Method

    NASA Astrophysics Data System (ADS)

    Y Tao, S.; Zhang, X. Z.; Cai, H. W.; Li, P.; Feng, Y.; Zhang, T. C.; Li, J.; Wang, W. S.; Zhang, X. K.

    2017-12-01

    The pulse current method for partial discharge detection is generally applied in type testing and other off-line tests of electrical equipment at delivery. After intensive analysis of the present situation and existing problems of partial discharge detection in switch cabinets, this paper designed the circuit principle and signal extraction method for partial discharge on-line detection based on a high-voltage presence indicating systems (VPIS), established a high voltage switch cabinet partial discharge on-line detection circuit based on the pulse current method, developed background software integrated with real-time monitoring, judging and analyzing functions, carried out a real discharge simulation test on a real-type partial discharge defect simulation platform of a 10KV switch cabinet, and verified the sensitivity and validity of the high-voltage switch cabinet partial discharge on-line monitoring device based on the pulse current method. The study presented in this paper is of great significance for switch cabinet maintenance and theoretical study on pulse current method on-line detection, and has provided a good implementation method for partial discharge on-line monitoring devices for 10KV distribution network equipment.

  12. Optimal Pulse Configuration Design for Heart Stimulation. A Theoretical, Numerical and Experimental Study.

    NASA Astrophysics Data System (ADS)

    Hardy, Neil; Dvir, Hila; Fenton, Flavio

    Existing pacemakers consider the rectangular pulse to be the optimal form of stimulation current. However, other waveforms for the use of pacemakers could save energy while still stimulating the heart. We aim to find the optimal waveform for pacemaker use, and to offer a theoretical explanation for its advantage. Since the pacemaker battery is a charge source, here we probe the stimulation current waveforms with respect to the total charge delivery. In this talk we present theoretical analysis and numerical simulations of myocyte ion-channel currents acting as an additional source of charge that adds to the external stimulating charge for stimulation purposes. Therefore, we find that as the action potential emerges, the external stimulating current can be reduced accordingly exponentially. We then performed experimental studies in rabbit and cat hearts and showed that indeed exponential truncated pulses with less total charge can still induce activation in the heart. From the experiments, we present curves showing the savings in charge as a function of exponential waveform and we calculated that the longevity of the pacemaker battery would be ten times higher for the exponential current compared to the rectangular waveforms. Thanks to Petit Undergraduate Research Scholars Program and NSF# 1413037.

  13. Bethe Ansatz for the Weakly Asymmetric Simple Exclusion Process and Phase Transition in the Current Distribution

    NASA Astrophysics Data System (ADS)

    Simon, Damien

    2011-03-01

    The probability distribution of the current in the asymmetric simple exclusion process is expected to undergo a phase transition in the regime of weak asymmetry of the jumping rates. This transition was first predicted by Bodineau and Derrida using a linear stability analysis of the hydrodynamical limit of the process and further arguments have been given by Mallick and Prolhac. However it has been impossible so far to study what happens after the transition. The present paper presents an analysis of the large deviation function of the current on both sides of the transition from a Bethe Ansatz approach of the weak asymmetry regime of the exclusion process.

  14. Electric current focusing efficiency in a graphene electric lens.

    PubMed

    Mu, Weihua; Zhang, Gang; Tang, Yunqing; Wang, Wei; Ou-Yang, Zhongcan

    2011-12-14

    In the present work, we study theoretically the electron wave's focusing phenomenon in a single-layered graphene pn junction (PNJ) and obtain the electric current density distribution of graphene PNJ, which is in good agreement with the qualitative result in previous numerical calculations (Cheianov et al 2007 Science, 315, 1252). In addition, we find that, for a symmetric PNJ, 1/4 of total electric current radiated from the source electrode can be collected by the drain electrode. Furthermore, this ratio reduces to 3/16 in a symmetric graphene npn junction. Our results obtained by the present analytical method provide a general design rule for an electric lens based on negative refractory index systems. © 2011 IOP Publishing Ltd

  15. Mars Sample Return Architecture Assessment Study

    NASA Astrophysics Data System (ADS)

    Centuori, S.; Hermosín, P.; Martín, J.; De Zaiacomo, G.; Colin, S.; Godfrey, A.; Myles, J.; Johnson, H.; Sachdev, T.; Ahmed, R.

    2018-04-01

    Current paper presents the results of ESA funded activity "Mars Sample Return Architecture Assessment Study" carried-out by DEIMOS Space, Lockheed Martin UK Ampthill, and MDA Corporation, where more than 500 mission design options have been studied.

  16. SAR observation and numerical modeling of tidal current wakes at the East China Sea offshore wind farm

    NASA Astrophysics Data System (ADS)

    Li, XiaoMing; Chi, Lequan; Chen, Xueen; Ren, YongZheng; Lehner, Susanne

    2014-08-01

    A TerraSAR-X (TS-X) Synthetic Aperture Radar (SAR) image acquired at the East China Sea offshore wind farm presents distinct wakes at a kilometer scale on the lee of the wind turbines. The presumption was that these wakes were caused by wind movement around turbine blades. However, wind analysis using spaceborne radiometer data, numerical weather prediction, and in situ measurements suggest that the prevailing wind direction did not align with the wakes. By analyzing measurement at the tidal gauge station and modeling of the tidal current field, these trailing wakes are interpreted to have formed when a strong tidal current impinged on the cylindrical monopiles of the wind turbines. A numerical simulation was further conducted to reproduce the tidal current wake under such conditions. Comparison of the simulated surface velocity in the wake region with the TS-X sea surface backscatter intensity shows a similar trend. Consequently, turbulence intensity (T.I.) of the tidal current wakes over multiple piles is studied using the TS-X observation. It is found that the T.I. has a logarithmic relation with distance. Furthermore, another case study showing wakes due to wind movement around turbine blades is presented to discuss the differences in the tidal current wakes and wind turbine wakes. The conclusion is drawn that small-scale wakes formed by interaction of the tidal current and the turbine piles could be also imaged by SAR when certain conditions are satisfied. The study is anticipated to draw more attentions to the impacts of offshore wind foundations on local hydrodynamic field.

  17. Performance of the LANSCE H^- Source and Low Energy Transport at Higher Peak Current

    NASA Astrophysics Data System (ADS)

    Pillai, Chandra; Stevens, Ralph; Fitzgerald, Daniel; Garnett, Robert; Ingllas, William; Merrill, Frank; Rybarcyk, Larry; Sander, Oscar

    1997-05-01

    The Los Alamos Neutron Science Center (LANSCE) 800 MeV linac facility uses a multicusp field, surface ion source to produce H^- beam for delivery to the Proton Storage Ring (PSR) and to the Weapon Neutron Research (WNR) areas. The source typically operates at a duty factor of 9.4% delivering a peak current of about 14 mA into the 750 keV LEBT. Each beam macropulse is chopped to create a sequence of 360 ns pulse, each with a 100 ns ``extraction notch'' for injection into PSR. The average current delivered to the short-pulse spallation target is nominally 70μA. One goal of the present PSR upgrade projects is an increase in the average beam current to 200μA. This will be accomplished by a combination of increased repetition rate (to 30 Hz), upgraded PSR bunchers, and a brighter H^- ion source that will produce higher peak current with lower beam emittance. The present ion source and injector system was studied to investigate the beam qualities of the source and the performance of the low energy transpot. The performance of the ion source at higher currents and the change in beam parameters in the low energy transport compared to those in the standard source conditions will be presented.

  18. Genetic Breeding and Diversity of the Genus Passiflora: Progress and Perspectives in Molecular and Genetic Studies

    PubMed Central

    Cerqueira-Silva, Carlos Bernard M.; Jesus, Onildo N.; Santos, Elisa S. L.; Corrêa, Ronan X.; Souza, Anete P.

    2014-01-01

    Despite the ecological and economic importance of passion fruit (Passiflora spp.), molecular markers have only recently been utilized in genetic studies of this genus. In addition, both basic genetic researches related to population studies and pre-breeding programs of passion fruit remain scarce for most Passiflora species. Considering the number of Passiflora species and the increasing use of these species as a resource for ornamental, medicinal, and food purposes, the aims of this review are the following: (i) to present the current condition of the passion fruit crop; (ii) to quantify the applications and effects of using molecular markers in studies of Passiflora; (iii) to present the contributions of genetic engineering for passion fruit culture; and (iv) to discuss the progress and perspectives of this research. Thus, the present review aims to summarize and discuss the relationship between historical and current progress on the culture, breeding, and molecular genetics of passion fruit. PMID:25196515

  19. Intrinsic Membrane Properties of Pre-oromotor Neurons in the Intermediate Zone of the Medullary Reticular Formation

    PubMed Central

    Venugopal, Sharmila; Boulant, Jack A.; Chen, Zhixiong; Travers, Joseph B.

    2010-01-01

    Neurons in the lower brainstem that control consummatory behavior are widely distributed in the reticular formation (RF) of the pons and medulla. The intrinsic membrane properties of neurons within this distributed system shape complex excitatory and inhibitory inputs from both orosensory and central structures implicated in homeostatic control to produce coordinated oromotor patterns. The current study explored the intrinsic membrane properties of neurons in the intermediate subdivision of the medullary reticular formation (IRt). Neurons in the IRt receive input from the overlying (gustatory) nucleus of the solitary tract and project to the oromotor nuclei. Recent behavioral pharmacology studies as well as computational modeling suggest that inhibition in the IRt plays an important role in the transition from a taste-initiated oromotor pattern of ingestion to one of rejection. The present study explored the impact of hyperpolarization on membrane properties. In response to depolarization, neurons responded with either a tonic discharge, an irregular/burst pattern or were spike-adaptive. A hyperpolarizing pre-pulse modulated the excitability of most (82%) IRt neurons to subsequent depolarization. Instances of both increased (30%) and decreased (52%) excitability were observed. Currents induced by the hyperpolarization included an outward 4-AP sensitive K+ current that suppressed excitability and an inward cation current that increased excitability. These currents are also present in other subpopulations of RF neurons that influence the oromotor nuclei and we discuss how these currents could alter ring characteristics to impact pattern generation. PMID:20338224

  20. Modified Johnson-Cook model incorporated with electroplasticity for uniaxial tension under a pulsed electric current

    NASA Astrophysics Data System (ADS)

    Kim, Moon-Jo; Jeong, Hye-Jin; Park, Ju-Won; Hong, Sung-Tae; Han, Heung Nam

    2018-01-01

    An empirical expression describing the electroplastic deformation behavior is suggested based on the Johnson-Cook (JC) model by adding several functions to consider both thermal and athermal electric current effects. Tensile deformation behaviors are carried out for an AZ31 magnesium alloy and an Al-Mg-Si alloy under pulsed electric current at various current densities with a fixed duration of electric current. To describe the flow curves under electric current, a modified JC model is proposed to take the electric current effect into account. Phenomenological descriptions of the adopted parameters in the equation are made. The modified JC model suggested in the present study is capable of describing the tensile deformation behaviors under pulsed electric current reasonably well.

  1. Taylor dispersion in wind-driven current

    NASA Astrophysics Data System (ADS)

    Li, Gang; Wang, Ping; Jiang, Wei-Quan; Zeng, Li; Li, Zhi; Chen, G. Q.

    2017-12-01

    Taylor dispersion associated with wind-driven currents in channels, shallow lakes and estuaries is essential to hydrological environmental management. For solute dispersion in a wind-driven current, presented in this paper is an analytical study of the evolution of concentration distribution. The concentration moments are intensively derived for an accurate presentation of the mean concentration distribution, up to the effect of kurtosis. The vertical divergence of concentration is then deduced by Gill's method of series expansion up to the fourth order. Based on the temporal evolution of the vertical concentration distribution, the dispersion process in the wind-driven current is concretely characterized. The uniform shear leads to a special symmetrical distribution of mean concentration free of skewness. The non-uniformity of vertical concentration is caused by convection and smeared out gradually by the effect of diffusion, but fails to disappear even at large times.

  2. Performance Study of Earth Networks Total Lightning Network using Rocket-Triggered Lightning Data in 2014

    NASA Astrophysics Data System (ADS)

    Heckman, S.

    2015-12-01

    Modern lightning locating systems (LLS) provide real-time monitoring and early warning of lightningactivities. In addition, LLS provide valuable data for statistical analysis in lightning research. It isimportant to know the performance of such LLS. In the present study, the performance of the EarthNetworks Total Lightning Network (ENTLN) is studied using rocket-triggered lightning data acquired atthe International Center for Lightning Research and Testing (ICLRT), Camp Blanding, Florida.In the present study, 18 flashes triggered at ICLRT in 2014 were analyzed and they comprise of 78negative cloud-to-ground return strokes. The geometric mean, median, minimum, and maximum for thepeak currents of the 78 return strokes are 13.4 kA, 13.6 kA, 3.7 kA, and 38.4 kA, respectively. The peakcurrents represent typical subsequent return strokes in natural cloud-to-ground lightning.Earth Networks has developed a new data processor to improve the performance of their network. Inthis study, results are presented for the ENTLN data using the old processor (originally reported in 2014)and the ENTLN data simulated using the new processor. The flash detection efficiency, stroke detectionefficiency, percentage of misclassification, median location error, median peak current estimation error,and median absolute peak current estimation error for the originally reported data from old processorare 100%, 94%, 49%, 271 m, 5%, and 13%, respectively, and those for the simulated data using the newprocessor are 100%, 99%, 9%, 280 m, 11%, and 15%, respectively. The use of new processor resulted inhigher stroke detection efficiency and lower percentage of misclassification. It is worth noting that theslight differences in median location error, median peak current estimation error, and median absolutepeak current estimation error for the two processors are due to the fact that the new processordetected more number of return strokes than the old processor.

  3. Studies in High Current Density Ion Sources for Heavy Ion Fusion Applications

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

    Chacon-Golcher, Edwin

    This dissertation develops diverse research on small (diameter ~ few mm), high current density (J ~ several tens of mA/cm 2) heavy ion sources. The research has been developed in the context of a programmatic interest within the Heavy Ion Fusion (HIF) Program to explore alternative architectures in the beam injection systems that use the merging of small, bright beams. An ion gun was designed and built for these experiments. Results of average current density yield () at different operating conditions are presented for K + and Cs + contact ionization sources and potassium aluminum silicate sources. Maximum valuesmore » for a K + beam of ~90 mA/cm 2 were observed in 2.3 μs pulses. Measurements of beam intensity profiles and emittances are included. Measurements of neutral particle desorption are presented at different operating conditions which lead to a better understanding of the underlying atomic diffusion processes that determine the lifetime of the emitter. Estimates of diffusion times consistent with measurements are presented, as well as estimates of maximum repetition rates achievable. Diverse studies performed on the composition and preparation of alkali aluminosilicate ion sources are also presented. In addition, this work includes preliminary work carried out exploring the viability of an argon plasma ion source and a bismuth metal vapor vacuum arc (MEVVA) ion source. For the former ion source, fast rise-times (~ 1 μs), high current densities (~ 100 mA/cm +) and low operating pressures (< 2 mtorr) were verified. For the latter, high but acceptable levels of beam emittance were measured (ε n ≤ 0.006 π· mm · mrad) although measured currents differed from the desired ones (I ~ 5mA) by about a factor of 10.« less

  4. Ramp compression of a metallic liner driven by a shaped 5 MA current on the SPHINX machine

    NASA Astrophysics Data System (ADS)

    D'Almeida, Thierry; Lassalle, Francis; Morell, Alain; Grunenwald, Julien; Zucchini, Frédéric; Loyen, Arnaud; Maysonnave, Thomas; Chuvatin, Alexandre

    2013-06-01

    SPHINX is a 6MA, 1- μs Linear Transformer Driver operated by the CEA Gramat (France) and primarily used for imploding Z-pinch loads for radiation effects studies. Among the options that are currently being considered for improving the generator performances, there is a compact Dynamic Load Current Amplifier (DLCM). A method for performing magnetic ramp compression experiments, without modifying the generator operation scheme, was developed using the DLCM to shape the initial current pulse. We present the overall experimental configuration chosen for these experiments, based on electrical and hydrodynamic simulations. Initial results obtained over a set of experiments on an aluminum cylindrical liner, ramp-compressed to a peak pressure of 23 GPa, are presented. Details of the electrical and Photonic Doppler Velocimetry (PDV) setups used to monitor and diagnose the ramp compression experiments are provided. Current profiles measured at various locations across the system, particularly the load current, agree with simulated current profile and demonstrate adequate pulse shaping by the DLCM. The liner inner free surface velocity measurements agree with the hydrocode results obtained using the measured load current as the input. Higher ramp pressure levels are foreseen in future experiments with an improved DLCM system.

  5. Swarm observation of field-aligned current and electric field in multiple arc systems

    NASA Astrophysics Data System (ADS)

    Wu, J.; Knudsen, D. J.; Gillies, M.; Donovan, E.; Burchill, J. K.

    2017-12-01

    It is often thought that auroral arcs are a direct consequence of upward field-aligned currents. In fact, the relation between currents and brightness is more complicated. Multiple auroral arc systems provide and opportunity to study this relation in detail. In this study, we have identified two types of FAC configurations in multiple parallel arc systems using ground-based optical data from the THEMIS all-sky imagers (ASIs), magnetometers and electric field instruments onboard the Swarm satellites during the period from December 2013 to March 2015. In type 1 events, each arc is an intensification within a broad, unipolar current sheet and downward currents only exist outside the upward current sheet. These types of events are termed "unipolar FAC" events. In type 2 events, multiple arc systems represent a collection of multiple up/down current pairs, which are termed as "multipolar FAC" events. Comparisons of these two types of FAC events are presented with 17 "unipolar FAC" events and 12 "multipolar FAC" events. The results show that "unipolar FAC" and "multipolar FAC" events have systematic differences in terms of MLT, arc width and separation, and dependence on substorm onset time. For "unipolar FAC" events, significant electric field enhancements are shown on the edges of the broad upward current sheet. Electric field fluctuations inside the multiple arc system can be large or small. For "multipolar FAC" events, a strong correlation between magnetic and electric field indicate uniform conductance within each upward current sheet. The electrodynamical structures of multiple arc systems presented in this paper represents a step toward understanding arc generation.

  6. A study on the influence of corona on currents and electromagnetic fields predicted by a nonlinear lightning return-stroke model

    NASA Astrophysics Data System (ADS)

    De Conti, Alberto; Silveira, Fernando H.; Visacro, Silvério

    2014-05-01

    This paper investigates the influence of corona on currents and electromagnetic fields predicted by a return-stroke model that represents the lightning channel as a nonuniform transmission line with time-varying (nonlinear) resistance. The corona model used in this paper allows the calculation of corona currents as a function of the radial electric field in the vicinity of the channel. A parametric study is presented to investigate the influence of corona parameters, such as the breakdown electric field and the critical electric field for the stable propagation of streamers, on predicted currents and electromagnetic fields. The results show that, regardless of the assumed corona parameters, the incorporation of corona into the nonuniform and nonlinear transmission line model under investigation modifies the model predictions so that they consistently reproduce most of the typical features of experimentally observed lightning electromagnetic fields and return-stroke speed profiles. In particular, it is shown that the proposed model leads to close vertical electric fields presenting waveforms, amplitudes, and decay with distance in good agreement with dart leader electric field changes measured in triggered lightning experiments. A comparison with popular engineering return-stroke models further confirms the model's ability to predict consistent electric field waveforms in the close vicinity of the channel. Some differences observed in the field amplitudes calculated with the different models can be related to the fact that current distortion, while present in the proposed model, is ultimately neglected in the considered engineering return-stroke models.

  7. Study of the time-resolved, 3-dimensional current density distribution in solid metallic liners at 1 MA

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

    Bott-Suzuki, S. C.; Cordaro, S. W.; Caballero Bendixsen, L. S.

    We present a study of the time varying current density distribution in solid metallic liner experiments at the 1MA level. Measurements are taken using an array of magnetic field probes which provide 2D triangulation of the average centroid of the drive current in the load at 3 discrete axial positions. These data are correlated with gated optical self-emission imaging which directly images the breakdown and plasma formation region. Results show that the current density is azimuthally non-uniform, and changes significantly throughout the 100ns experimental timescale. Magnetic field probes show clearly motion of the current density around the liner azimuth overmore » 10ns timescales. If breakdown is initiated at one azimuthal location, the current density remains non-uniform even over large spatial extents throughout the current drive. The evolution timescales are suggestive of a resistive diffusion process or uneven current distributions among simultaneously formed but discrete plasma conduction paths.« less

  8. Study of the time-resolved, 3-dimensional current density distribution in solid metallic liners at 1 MA

    DOE PAGES

    Bott-Suzuki, S. C.; Cordaro, S. W.; Caballero Bendixsen, L. S.; ...

    2016-09-01

    We present a study of the time varying current density distribution in solid metallic liner experiments at the 1MA level. Measurements are taken using an array of magnetic field probes which provide 2D triangulation of the average centroid of the drive current in the load at 3 discrete axial positions. These data are correlated with gated optical self-emission imaging which directly images the breakdown and plasma formation region. Results show that the current density is azimuthally non-uniform, and changes significantly throughout the 100ns experimental timescale. Magnetic field probes show clearly motion of the current density around the liner azimuth overmore » 10ns timescales. If breakdown is initiated at one azimuthal location, the current density remains non-uniform even over large spatial extents throughout the current drive. The evolution timescales are suggestive of a resistive diffusion process or uneven current distributions among simultaneously formed but discrete plasma conduction paths.« less

  9. Investigation of Unsteady Flow Interaction Between an Ultra-Compact Inlet and a Transonic Fan

    NASA Technical Reports Server (NTRS)

    Hah, Chunill; Rabe, Douglas; Scribben, Angie

    2015-01-01

    In the present study, unsteady flow interaction between an ultra-compact inlet and a transonic fan stage is investigated. Future combat aircraft require ultra-compact inlet ducts as part of an integrated, advanced propulsion system to improve air vehicle capability and effectiveness to meet future mission needs. The main purpose of the study is to advance the current understanding of the flow interaction between two different ultra-compact inlets and a transonic fan for future design applications. Both URANS and LES approaches are used to calculate the unsteady flow field and are compared with the available measured data. The present study indicates that stall inception is mildly affected by the distortion pattern generated by the inlet with the current test set-up. The numerical study indicates that the inlet distortion pattern decays significantly before it reaches the fan face for the current configuration. Numerical results with a shorter distance between the inlet and fan show that counter-rotating vortices near the rotor tip due to the serpentine diffuser affects fan characteristics significantly.

  10. When does the future begin? Time metrics matter, connecting present and future selves.

    PubMed

    Lewis, Neil A; Oyserman, Daphna

    2015-06-01

    People assume they should attend to the present; their future self can handle the future. This seemingly plausible rule of thumb can lead people astray, in part because some future events require current action. In order for the future to energize and motivate current action, it must feel imminent. To create this sense of imminence, we manipulated time metric--the units (e.g., days, years) in which time is considered. People interpret accessible time metrics in two ways: If preparation for the future is under way (Studies 1 and 2), people interpret metrics as implying when a future event will occur. If preparation is not under way (Studies 3-5), they interpret metrics as implying when preparation should start (e.g., planning to start saving 4 times sooner for a retirement in 10,950 days instead of 30 years). Time metrics mattered not because they changed how distal or important future events felt (Study 6), but because they changed how connected and congruent their current and future selves felt (Study 7). © The Author(s) 2015.

  11. Transfer of Information from Short- to Long-Term Memory

    ERIC Educational Resources Information Center

    Modigliani, Vito; Seamon, John G.

    1974-01-01

    The present study examined current hypotheses concerning information transfer from short-term memory (STM) to long-term memory (LTM) using a Peterson STM task with word triplets presented over retention intervals of 0, 3, 6, 9, and 18 sec. (Editor)

  12. Blocked versus randomized presentation modes differentially modulate feedback-related negativity and P3b amplitudes.

    PubMed

    Pfabigan, Daniela M; Zeiler, Michael; Lamm, Claus; Sailer, Uta

    2014-04-01

    Electrophysiological studies on feedback processing typically use a wide range of feedback stimuli which might not always be comparable. The current study investigated whether two indicators of feedback processing - feedback-related negativity (FRN) and P3b - differ for feedback stimuli with explicit (facial expressions) or assigned valence information (symbols). In addition, we assessed whether presenting feedback in either a trial-by-trial or a block-wise fashion affected these ERPs. EEG was recorded in three experiments while participants performed a time estimation task and received two different types of performance feedback. Only P3b amplitudes varied consistently in response to feedback type for both presentation types. Moreover, the blocked feedback type presentation yielded more distinct FRN peaks, higher effect sizes, and a significant relation between FRN amplitudes and behavioral task performance measures. Both stimulus type and presentation mode may provoke systematic changes in feedback-related ERPs. The current findings point at important potential confounds that need to be controlled for when designing FRN or P3b studies. Studies investigating P3b amplitudes using mixed types of stimuli have to be interpreted with caution. Furthermore, we suggest implementing a blocked presentation format when presenting different feedback types within the same experiment. Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  13. Assessing Student Scientific Expression Using Media: The Media-Enhanced Science Presentation Rubric (MESPR)

    ERIC Educational Resources Information Center

    Mott, Michael S.; Chessin, Debby A.; Sumrall, William J.; Rutherford, Angela S.; Moore, Virginia J.

    2011-01-01

    The current study evaluated an assessment designed to dually promote student understanding of the experimental method and student ability to include digital and visual qualities in their presentations of scientific experiment results. The rubric, the Media-Enhanced Science Presentation Rubric (MESPR) focuses teacher-student dialogue along the…

  14. Global Citizenship Education in School Curricula. A Polish Perspective

    ERIC Educational Resources Information Center

    Leek, Joanna

    2016-01-01

    The purpose of this study is to present global citizenship education from a Polish perspective. Analyzing the issue, the first part of this paper presents the development of citizenship education, followed by the current status of global citizenship education in Polish schools. In the second part of the study I draw attention to national curricula…

  15. Block Play: Spatial Language with Preschool and School-Aged Children

    ERIC Educational Resources Information Center

    Cohen, Lynn E.; Emmons, Janet

    2017-01-01

    Implementing a play-based curriculum presents challenges for pre-service and in-service teachers given the current climate of standards and didactic pedagogies. This study highlights the value of playful learning and its rightful place in early childhood classrooms for children of all ages. The purpose of the present study was to investigate the…

  16. The Education of Behavior Disordered Students. Report of the West Virginia Task Force.

    ERIC Educational Resources Information Center

    West Virginia State Dept. of Education, Charleston. Bureau of Learning Systems.

    The report presents findings of a West Virginia task force on a program study for behavior disordered students in early childhood education, middle childhood education, and adolescent education. The first section presents a synopsis of studies on current research and best practices in the education of behavior disordered students. The conclusions…

  17. Examining Mental Health Differences among Transfer University Students Seeking Counseling Services

    ERIC Educational Resources Information Center

    Daltry, Rachel; Mehr, Kristin E.

    2016-01-01

    This brief report was designed as a follow-up to a study that found that compared to nontransfer students that presented to the counseling center, transfer students who presented to the counseling center endorsed higher levels of symptoms of depression and social anxiety, as well as more academic and family problems. The current study investigated…

  18. Prompting Children to Reason Proportionally: Processing Discrete Units as Continuous Amounts

    ERIC Educational Resources Information Center

    Boyer, Ty W.; Levine, Susan C.

    2015-01-01

    Recent studies reveal that children can solve proportional reasoning problems presented with continuous amounts that enable intuitive strategies by around 6 years of age but have difficulties with problems presented with discrete units that tend to elicit explicit count-and-match strategies until at least 10 years of age. The current study tests…

  19. The Presentation of Animals in English as an Additional Language Coursebooks

    ERIC Educational Resources Information Center

    Jacobs, George M.; Jiexin, Teh; Michael, Joyce J.

    2016-01-01

    Education materials can be analysed in many ways. The current study analysed EAL (English as an Additional Language) coursebooks as to the presentation of nonhuman animals in the books. The study examined 22 EAL coursebooks. The research looked at the percentage of activities that contained animals in the coursebooks, what types of animals were…

  20. The Public Community College in America: Its History, Present Condition, and Future Outlook with Special Reference to Finance.

    ERIC Educational Resources Information Center

    Edwards, Nancy Joan

    The development, current status, and future prospects of community colleges are examined in this study with special emphasis on finance and funding concerns. Introductory material outlines study objectives, methodology, and purposes; defines key terms; and emphasizes the importance of college planning. Chapter 1 presents a history of the community…

  1. PESTE Factors in Developing a Framework for E-Learning

    ERIC Educational Resources Information Center

    Graham, Deryn

    2007-01-01

    This article describes the development of a framework for e-learning and presents the findings of a study investigating whether the use of blended learning can fulfil or at least accommodate some of the human requirements presently neglected by current e-learning systems. The study evaluated the in-house system, Teachmat, and discussed how the use…

  2. Adolescent Self-Presentation on Facebook and Its Impact on Self-Esteem

    ERIC Educational Resources Information Center

    Metzler, Anna; Scheithauer, Herbert

    2015-01-01

    A considerable body of research has examined the association between self-presentation on social networking sites and personality in adults. Yet, there is a lack of corresponding research on adolescents as well as studies on alternative measures of personality traits of the self. The current study investigates, using a cross-sectional multi-method…

  3. Validity of one-repetition maximum predictive equations in men with spinal cord injury.

    PubMed

    Ribeiro Neto, F; Guanais, P; Dornelas, E; Coutinho, A C B; Costa, R R G

    2017-10-01

    Cross-sectional study. The study aimed (a) to test the cross-validation of current one-repetition maximum (1RM) predictive equations in men with spinal cord injury (SCI); (b) to compare the current 1RM predictive equations to a newly developed equation based on the 4- to 12-repetition maximum test (4-12RM). SARAH Rehabilitation Hospital Network, Brasilia, Brazil. Forty-five men aged 28.0 years with SCI between C6 and L2 causing complete motor impairment were enrolled in the study. Volunteers were tested, in a random order, in 1RM test or 4-12RM with 2-3 interval days. Multiple regression analysis was used to generate an equation for predicting 1RM. There were no significant differences between 1RM test and the current predictive equations. ICC values were significant and were classified as excellent for all current predictive equations. The predictive equation of Lombardi presented the best Bland-Altman results (0.5 kg and 12.8 kg for mean difference and interval range around the differences, respectively). The two created equation models for 1RM demonstrated the same and a high adjusted R 2 (0.971, P<0.01), but different SEE of measured 1RM (2.88 kg or 5.4% and 2.90 kg or 5.5%). All 1RM predictive equations are accurate to assess individuals with SCI at the bench press exercise. However, the predictive equation of Lombardi presented the best associated cross-validity results. A specific 1RM prediction equation was also elaborated for individuals with SCI. The created equation should be tested in order to verify whether it presents better accuracy than the current ones.

  4. Current problems in applied mathematics and mathematical modeling

    NASA Astrophysics Data System (ADS)

    Alekseev, A. S.

    Papers are presented on mathematical modeling noting applications to such fields as geophysics, chemistry, atmospheric optics, and immunology. Attention is also given to models of ocean current fluxes, atmospheric and marine interactions, and atmospheric pollution. The articles include studies of catalytic reactors, models of global climate phenomena, and computer-assisted atmospheric models.

  5. The Journal from the Northwest Center for the Study of Correctional Education, 1996.

    ERIC Educational Resources Information Center

    Clare, Warren L., Ed.

    1996-01-01

    This journal presents a forum for discussion and research related to correctional education programs and their effects on students. This inaugural issue contains the following articles: (1) "The Position of Correctional Education in the Current Crime Dilemma," by the editors, describing problems currently facing correctional administrators and key…

  6. Current Developments in Community College Performance Funding

    ERIC Educational Resources Information Center

    D'Amico, Mark M.; Friedel, Janice N.; Katsinas, Stephen G.; Thornton, Zoë M.

    2014-01-01

    Since the initiation of performance funding in Tennessee in the late 1970s, approximately 30 states have, at some point, attempted a funding model that includes performance on a set of indicators. The purpose of the present study was to capture the current status of performance funding in public statewide community college systems and to assess…

  7. The Tense Situation of Slavic: Past, Present, Future.

    ERIC Educational Resources Information Center

    Cooper, Henry R., Jr.

    1998-01-01

    Discusses the challenges and difficulties of Slavic languages, a field that is notoriously cyclical and is currently at the bottom of a cycle. The article chronicles the history of Slavic studies in relation to political developments since World War II, draws parallels between current trends in Slavic and other modern language programs, and sees…

  8. Postscript: Winnowing out Some Take-Home Points

    ERIC Educational Resources Information Center

    Botvinick, Matthew M.; Plaut, David C.

    2009-01-01

    Presents a postscript to the current authors' response to the comments by J. S. Bowers, M. F. Damian, and C. J. Davis on the current authors' original article, "Short-term memory for serial order: A recurrent neural network model,". Here, Botvinick and Plaut address Bowers et al's assertions that neurophysiological studies that have reported…

  9. A Study of Current Trends and Issues Related to Technical/Engineering Design Graphics.

    ERIC Educational Resources Information Center

    Clark, Aaron C.; Scales Alice

    2000-01-01

    Presents results from a survey of engineering design graphics educators who responded to questions related to current trends and issues in the profession of graphics education. Concludes that there is a clear trend in institutions towards the teaching of constraint-based modeling and computer-aided manufacturing. (Author/YDS)

  10. Emergency Skills Resources for Range-Related Driver Education.

    ERIC Educational Resources Information Center

    Council, Forrest M.; And Others

    The document presents a rationale for expanding the current emergency skills curriculum in North Carolina's 18 multi-vehicle range laboratories for driver education, and includes a review of past and current programs in other locations, a review of past North Carolina accident studies directly related to this area, and a recommended set of…

  11. Mental disorders in Italian prisoners: results of the REDiMe study.

    PubMed

    Macciò, Annalisa; Meloni, Francesca Romana; Sisti, Davide; Rocchi, Marco Bruno Luigi; Petretto, Donatella Rita; Masala, Carmelo; Preti, Antonio

    2015-02-28

    The goal of the study was to estimate the prevalence of current and lifetime mental disorders in a consecutive sample (n=300) of detainees and prison inmates held in an Italian prison and compare it with the prevalence observed in a sample randomized from the community (n=300) within the same age interval (18-55 years) and sex proportion of prisoners, and with a similar socio-economic status. Psychiatric disorders were identified with the Mini International Neuropsychiatric Interview (MINI). Current psychiatric disorders were present in 58.7% of prisoners and 8.7% of the comparison group. Lifetime psychiatric disorders were present in 88.7% of prisoners and 15.7% of the comparison group. Current anxiety disorders and current stress-related disorders were related to prisoners serving their first-ever prison sentence. A variable fraction of prisoners with an ongoing psychopathology is not diagnosed or does not receive proper treatment. The provision of effective treatment to prisoners with psychiatric disorders might have potentially substantial public health benefits. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  12. Perspectives on hypersonic viscous flow research

    NASA Technical Reports Server (NTRS)

    Cheng, H. K.

    1993-01-01

    Issues and advances in current hypersonic flow research perceived to be of interest in theoretical fluid/gas dynamics are reviewed. Particular attention is given to the hypersonic aircraft as waverider, computational methods and theoretical development in the study of viscous interaction, and boundary-layer instability and transition studies. In the present framework the study of viscous hypersonic flow faces transition problems of two kinds which represent the two major areas of current research: the turbulence transition in the high Re range and the transition to the free-molecule limit.

  13. Recent trends for practical rehabilitation robotics, current challenges and the future.

    PubMed

    Yakub, Fitri; Md Khudzari, Ahmad Zahran; Mori, Yasuchika

    2014-03-01

    This paper presents and studies various selected literature primarily from conference proceedings, journals and clinical tests of the robotic, mechatronics, neurology and biomedical engineering of rehabilitation robotic systems. The present paper focuses of three main categories: types of rehabilitation robots, key technologies with current issues and future challenges. Literature on fundamental research with some examples from commercialized robots and new robot development projects related to rehabilitation are introduced. Most of the commercialized robots presented in this paper are well known especially to robotics engineers and scholars in the robotic field, but are less known to humanities scholars. The field of rehabilitation robot research is expanding; in light of this, some of the current issues and future challenges in rehabilitation robot engineering are recalled, examined and clarified with future directions. This paper is concluded with some recommendations with respect to rehabilitation robots.

  14. Hydrodynamic measurements in Suisun Bay, California, 1992-93

    USGS Publications Warehouse

    Gartner, Jeffrey W.; Burau, Jon R.

    1999-01-01

    Sea level, velocity, temperature, and salinity (conductivity and temperature) data collected in Suisun Bay, California, from December 11, 1992, through May 31, 1993, by the U.S. Geological Survey are documented in this report. Sea-level data were collected at four locations and temperature and salinity data were collected at seven locations. Velocity data were collected at three locations using acoustic Doppler current profilers and at four other locations using point velocity meters. Sea-level and velocity data are presented in three forms (1) harmonic analysis results, (2) time-series plots (sea level, current speed, and current direction versus time), and (3) time-series plots of the low-pass filtered data. Temperature and salinity data are presented as plots of raw and low-pass filtered time series. The velocity and salinity data collected during this study document a period when the residual current patterns and salt field were significantly altered by large Delta outflow (three peaks in excess of 2,000 cubic meters per second). Residual current profiles were consistently seaward with magnitudes that fluctuated primarily in concert with Delta outflow and secondarily with the spring-neap tide cycle. The freshwater inputs advected salinity seaward of Suisun Bay for most of this study. Except for a 10-day period at the beginning of the study, dynamically significant salinities (>2) were seaward of Suisun Bay, which resulted in little or no gravitational circulation transport.

  15. Howthe IMF By induces a By component in the closed magnetosphere and how it leads to asymmetric currents and convection patterns in the two hemispheres

    NASA Astrophysics Data System (ADS)

    Tenfjord, Paul; Østgaard, Nikolai; Snekvik, Kristian; Reistad, Jone; Magnus Laundal, Karl; Haaland, Stein; Milan, Steve

    2016-04-01

    We describe the effects of the interplanetary magnetic field (IMF) By component on the coupling between the solar wind and magnetosphere-ionosphere system using AMPERE observations and MHD simulations. We show how By is induced on closed magnetospheric field lines on both the dayside and nightside. The magnetosphere imposes asymmetric forces on the ionosphere, and the effects on the ionospheric flow are characterized by distorted convection cell patterns, often referred to as "banana" and "orange" cell patterns. The flux asymmetrically added to the lobes results in a nonuniform induced By in the closed magnetosphere. We present a mechanism that predicts asymmetric Birkeland currents at conjugate foot points. Asymmetric Birkeland currents are created as a consequence of y directed tension contained in the return flow. Associated with these currents, we expect aurora and fast localized ionospheric azimuthal flows present in one hemisphere but not necessarily in the other. We present a statistical study where we show that these processes should occur on timescales of about 30 minutes after the IMF By has arrived at the magnetopause. We also present an event with simultaneous global imaging of the aurora and SuperDARN measurements from both hemisphere. The event is interpreted as an example of the of the proposed asymmetric current mechanism.

  16. Birkeland currents during substorms: Statistical evidence for intensification of Regions 1 and 2 currents after onset and a localized signature of auroral dimming

    NASA Astrophysics Data System (ADS)

    Coxon, John C.; Rae, I. Jonathan; Forsyth, Colin; Jackman, Caitriona M.; Fear, Robert C.; Anderson, Brian J.

    2017-06-01

    We conduct a superposed epoch analysis of Birkeland current densities from AMPERE (Active Magnetosphere and Planetary Electrodynamics Response Experiment) using isolated substorm expansion phase onsets identified by an independently derived data set. In order to evaluate whether R1 and R2 currents contribute to the substorm current wedge, we rotate global maps of Birkeland currents into a common coordinate system centered on the magnetic local time of substorm onset. When the latitude of substorm is taken into account, it is clear that both R1 and R2 current systems play a role in substorm onset, contrary to previous studies which found that R2 current did not contribute. The latitude of substorm onset is colocated with the interface between R1 and R2 currents, allowing us to infer that R1 current closes just tailward and R2 current closes just earthward of the associated current disruption in the tail. AMPERE is the first data set to give near-instantaneous measurements of Birkeland current across the whole polar cap, and this study addresses apparent discrepancies in previous studies which have used AMPERE to examine the morphology of the substorm current wedge. Finally, we present evidence for an extremely localized reduction in current density immediately prior to substorm onset, and we interpret this as the first statistical signature of auroral dimming in Birkeland current.

  17. 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.

  18. A phenomenological study of photon production in low energy neutrino nucleon scattering

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

    Jenkins, James P; Goldman, Terry J

    2009-01-01

    Low energy photon production is an important background to many current and future precision neutrino experiments. We present a phenomenological study of t-channel radiative corrections to neutral current neutrino nucleus scattering. After introducing the relevant processes and phenomenological coupling constants, we will explore the derived energy and angular distributions as well as total cross-section predictions along with their estimated uncertainties. This is supplemented throughout with comments on possible experimental signatures and implications. We conclude with a general discussion of the analysis in the context of complimentary methodologies. This is based on a talk presented at the DPF 2009 meeting inmore » Detroit MI.« less

  19. Io. [history of studies and current level of understanding of this satellite

    NASA Technical Reports Server (NTRS)

    Nash, Douglas B.; Yoder, Charles F.; Carr, Michael H.; Gradie, Jonathan; Hunten, Donald M.

    1986-01-01

    The present work reviews the history of Io studies and describes the current level of understanding of Io's physics, chemistry, geology, orbital dynamics, and geophysics. Consideration is given to the satellite's internal, superficial, atmospheric, plasma, and magnetospheric properties and how they interrelate. A pictorial map of Io's surface based on Voyager 1 and 2 images is presented. It is found that Io's surface color and spectra are dominated by sulfur compounds which may include various sulfur allotropes. Volcanic processes yielding three kinds of surface features (vent regions, plains, and mountains) dominate Io's surface geology. The Io plasma torus corotates with Jupiter's magnetic field in the plane of Jupiter's centrifugal equator centered at Io's orbital radius.

  20. Marginal regression approach for additive hazards models with clustered current status data.

    PubMed

    Su, Pei-Fang; Chi, Yunchan

    2014-01-15

    Current status data arise naturally from tumorigenicity experiments, epidemiology studies, biomedicine, econometrics and demographic and sociology studies. Moreover, clustered current status data may occur with animals from the same litter in tumorigenicity experiments or with subjects from the same family in epidemiology studies. Because the only information extracted from current status data is whether the survival times are before or after the monitoring or censoring times, the nonparametric maximum likelihood estimator of survival function converges at a rate of n(1/3) to a complicated limiting distribution. Hence, semiparametric regression models such as the additive hazards model have been extended for independent current status data to derive the test statistics, whose distributions converge at a rate of n(1/2) , for testing the regression parameters. However, a straightforward application of these statistical methods to clustered current status data is not appropriate because intracluster correlation needs to be taken into account. Therefore, this paper proposes two estimating functions for estimating the parameters in the additive hazards model for clustered current status data. The comparative results from simulation studies are presented, and the application of the proposed estimating functions to one real data set is illustrated. Copyright © 2013 John Wiley & Sons, Ltd.

  1. Results of EPA Pilot Studies on Arsenic Removal

    EPA Science Inventory

    This presentation will summarize the results of several projects of the USEPA Arsenic Demonstration Program. The presentation will begin with a summary of the current national compliance data of the arsenic regulation including the number and location of MCL violations. The sec...

  2. Classroom Tips.

    ERIC Educational Resources Information Center

    Crain, Cheryl

    1994-01-01

    Presents six teaching ideas from teachers in Foothills Schools, Alberta, Canada. Includes suggested activities on local government, computer uses in social studies, Canadian history, current events, and world studies. Provides models of a passport application, passports, and visas. (CFR)

  3. A Study of Convergence of the PMARC Matrices Applicable to WICS Calculations

    NASA Technical Reports Server (NTRS)

    Ghosh, Amitabha

    1997-01-01

    This report discusses some analytical procedures to enhance the real time solutions of PMARC matrices applicable to the Wall Interference Correction Scheme (WICS) currently being implemented at the 12 foot Pressure Tunnel. WICS calculations involve solving large linear systems in a reasonably speedy manner necessitating exploring further improvement in solution time. This paper therefore presents some of the associated theory of the solution of linear systems. Then it discusses a geometrical interpretation of the residual correction schemes. Finally some results of the current investigation are presented.

  4. A Study of Convergence of the PMARC Matrices Applicable to WICS Calculations

    NASA Technical Reports Server (NTRS)

    Ghosh, Amitabha

    1997-01-01

    This report discusses some analytical procedures to enhance the real time solutions of PMARC matrices applicable to the Wall Interference Correction Scheme (WICS) currently being implemented at the 12 foot Pressure Tunell. WICS calculations involve solving large linear systems in a reasonably speedy manner necessitating exploring further improvement in solution time. This paper therefore presents some of the associated theory of the solution of linear systems. Then it discusses a geometrical interpretation of the residual correction schemes. Finally, some results of the current investigation are presented.

  5. 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.

  6. Study of problem of waste chemical current sources in Russia and in European countries

    NASA Astrophysics Data System (ADS)

    Zilenina, V. G.; Ulanova, O. V.; Dornack, C.

    2017-10-01

    This article gives a comparative analysis of handling waste chemical current sources in Russia and in the European countries, presents the effective international documents (Directives, acts) and national legislative acts (state standards, building codes, governmental decrees, etc.), demonstrates the mechanisms for disposal and recycling of waste in the European Union countries. Along with the data of the research works, conducted in other countries during many yearsб it presents the experimental data on leaching out heavy metals from chemical current sources by municipal solid waste landfill filtrate, depending on the morphological composition of domestic waste in the city of Irkutsk. An important point described in the article, is assessment and prediction of negative impact produced on the environment.

  7. Association between previous enterobiasis and current wheezing: evaluation of 1018 children.

    PubMed

    Bahceciler, Nerin N; Ozdemir, Cevdet; Kucukosmanoglu, Ercan; Arikan, Cigdem; Over, Ufuk; Karavelioglu, Salim; Akkoc, Tunc; Yazi, Didem; Yesil, Ozlem; Soysal, Ahmet; Bakir, Mustafa; Barlan, Isil B

    2007-01-01

    The aim of this study was to investigate the association between parasitosis and allergy. We surveyed all children aged 4-12 years living in poor hygienic conditions in a shantytown of Istanbul. After obtaining data from the International Study of Asthma and Allergies in Childhood (ISAAC) and an additional questionnaire, performing a skin-prick test (SPT), and determining total IgE, stool and perianal tape specimens were obtained from 1018 participating children. The prevalence of past episodes of wheezing, current wheezing, asthma, and rhinitis was 31, 14.6, 10.7, and 26.2%, respectively. Parasitosis was present in 49.1%, Enterobius vermicularis (23.3%), being the most common. A history of treatment for enterobiasis was present in 37%. Comparison of children with and without current enterobiasis revealed no significant difference in allergic manifestations and SPT results, except for serum total IgE level (p = 0.018), whereas children with previous enterobiasis were more likely to have current wheezing (p = 0.012). Current wheezers were more likely to have previous enterobiasis (p = 0.01) and a higher maternal employment level (p = 0.036) when compared with those without. According to logistic regression analysis, covariables significantly positively related with current wheezing were previous enterobiasis (p = 0.003) and being < or =5 years of age (p = 0.043), whereas being the first child of the family (p = 0.043) was negatively related. A previous infection with E. vermicularis was found to potentiate current wheezing in a population living in a shantytown in Istanbul.

  8. Dual optimization method of radiofrequency and quasistatic field simulations for reduction of eddy currents generated on 7T radiofrequency coil shielding.

    PubMed

    Zhao, Yujuan; Zhao, Tiejun; Raval, Shailesh B; Krishnamurthy, Narayanan; Zheng, Hai; Harris, Chad T; Handler, William B; Chronik, Blaine A; Ibrahim, Tamer S

    2015-11-01

    To optimize the design of radiofrequency (RF) shielding of transmit coils at 7T and reduce eddy currents generated on the RF shielding when imaging with rapid gradient waveforms. One set of a four-element, 2 × 2 Tic-Tac-Toe head coil structure was selected and constructed to study eddy currents on the RF coil shielding. The generated eddy currents were quantitatively studied in the time and frequency domains. The RF characteristics were studied using the finite difference time domain method. Five different kinds of RF shielding were tested on a 7T MRI scanner with phantoms and in vivo human subjects. The eddy current simulation method was verified by the measurement results. Eddy currents induced by solid/intact and simple-structured slotted RF shielding significantly distorted the gradient fields. Echo-planar images, B1+ maps, and S matrix measurements verified that the proposed slot pattern suppressed the eddy currents while maintaining the RF characteristics of the transmit coil. The presented dual-optimization method could be used to design RF shielding and reduce the gradient field-induced eddy currents while maintaining the RF characteristics of the transmit coil. © 2014 Wiley Periodicals, Inc.

  9. Flexible bottom-gate graphene transistors on Parylene C substrate and the effect of current annealing

    PubMed Central

    Kim, Hyungsoo; Bong, Jihye; Mikael, Solomon; Kim, Tong June; Williams, Justin C.; Ma, Zhenqiang

    2016-01-01

    Flexible graphene transistors built on a biocompatible Parylene C substrate would enable active circuitry to be integrated into flexible implantable biomedical devices. An annealing method to improve the performance of a flexible transistor without damaging the flexible substrate is also desirable. Here, we present a fabrication method of a flexible graphene transistor with a bottom-gate coplanar structure on a Parylene C substrate. Also, a current annealing method and its effect on the device performance have been studied. The localized heat generated by the current annealing method improves the drain current, which is attributed to the decreased contact resistance between graphene and S/D electrodes. A maximum current annealing power in the Parylene C-based graphene transistor has been extracted to provide a guideline for an appropriate current annealing. The fabricated flexible graphene transistor shows a field-effect mobility, maximum transconductance, and a Ion/Ioff ratio of 533.5 cm2/V s, 58.1 μS, and 1.76, respectively. The low temperature process and the current annealing method presented here would be useful to fabricate two-dimensional materials-based flexible electronics. PMID:27795570

  10. Assimilation of the seabird and ship drift data in the north-eastern sea of Japan into an operational ocean nowcast/forecast system

    PubMed Central

    Miyazawa, Yasumasa; Guo, Xinyu; Varlamov, Sergey M.; Miyama, Toru; Yoda, Ken; Sato, Katsufumi; Kano, Toshiyuki; Sato, Keiji

    2015-01-01

    At the present time, ocean current is being operationally monitored mainly by combined use of numerical ocean nowcast/forecast models and satellite remote sensing data. Improvement in the accuracy of the ocean current nowcast/forecast requires additional measurements with higher spatial and temporal resolution as expected from the current observation network. Here we show feasibility of assimilating high-resolution seabird and ship drift data into an operational ocean forecast system. Data assimilation of geostrophic current contained in the observed drift leads to refinement in the gyre mode events of the Tsugaru warm current in the north-eastern sea of Japan represented by the model. Fitting the observed drift to the model depends on ability of the drift representing geostrophic current compared to that representing directly wind driven components. A preferable horizontal scale of 50 km indicated for the seabird drift data assimilation implies their capability of capturing eddies with smaller horizontal scale than the minimum scale of 100 km resolved by the satellite altimetry. The present study actually demonstrates that transdisciplinary approaches combining bio-/ship- logging and numerical modeling could be effective for enhancement in monitoring the ocean current. PMID:26633309

  11. Incorporating Multiple Secondary Targets into Learning Trials for Individuals with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Nottingham, Casey L.; Vladescu, Jason C.; Kodak, Tiffany; Kisamore, April N.

    2017-01-01

    The current study examined the outcome of presenting multiple secondary targets in learning trials for individuals with autism spectrum disorder. We compared conditions in which (a) a secondary target was presented in the antecedent and consequence of trials, (b) two secondary targets were presented in the consequence of trials, (c) one secondary…

  12. Increasing Instructional Efficiency by Presenting Additional Stimuli in Learning Trials for Children with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Vladescu, Jason C.; Kodak, Tiffany M.

    2013-01-01

    The current study examined the effectiveness and efficiency of presenting secondary targets within learning trials for 4 children with an autism spectrum disorder. Specifically, we compared 4 instructional conditions using a progressive prompt delay. In 3 conditions, we presented secondary targets in the antecedent or consequence portion of…

  13. Autism Spectrum Disorder Phenotype in Children with Ambulatory Cerebral Palsy: A Descriptive Cross-Sectional Study

    ERIC Educational Resources Information Center

    Smile, S.; Dupuis, A.; MacArthur, C.; Roberts, W.; Fehlings, D.

    2013-01-01

    The current study aims to describe the cognitive profile, autism profile, medical and behavioral presentation of children with a dual diagnosis of cerebral palsy (CP) and autism spectrum disorder (ASD). Little is known about the dual presentation of CP and ASD. Timely diagnosis is imperative as early intervention may impact a child's developmental…

  14. The Politics of Endangered Species.

    ERIC Educational Resources Information Center

    Lipscomb, Fran

    1982-01-01

    Presents background information and teaching suggestions about endangered species for social studies teachers. Discusses political processes, economics, current events, and ethics. Lists resource information. (DC)

  15. Cannabis Use Disorder and Suicide Attempts in Iraq/Afghanistan-Era Veterans

    PubMed Central

    Kimbrel, Nathan A.; Newins, Amie R.; Dedert, Eric A.; Van Voorhees, Elizabeth E.; Elbogen, Eric B.; Naylor, Jennifer C.; Wagner, H. Ryan; Brancu, Mira; Beckham, Jean C.; Calhoun, Patrick S.

    2017-01-01

    The objective of the present research was to examine the association between lifetime cannabis use disorder (CUD), current suicidal ideation, and lifetime history of suicide attempts in a large and diverse sample of Iraq/Afghanistan-era veterans (N = 3,233) using a battery of well-validated instruments. As expected, CUD was associated with both current suicidal ideation (OR = 1.683, p = 0.008) and lifetime suicide attempts (OR = 2.306, p < 0.0001), even after accounting for the effects of sex, posttraumatic stress disorder, depression, alcohol use disorder, non-cannabis drug use disorder, history of childhood sexual abuse, and combat exposure. Thus, the findings from the present study suggest that CUD may be a unique predictor of suicide attempts among Iraq/Afghanistan-era veterans; however, a significant limitation of the present study was its cross-sectional design. Prospective research aimed at understanding the complex relationship between CUD, mental health problems, and suicidal behavior among veterans is clearly needed at the present time. PMID:28129565

  16. Ulnar neuropathy at wrist: entrapment at a very "congested" site.

    PubMed

    Coraci, Daniele; Loreti, Claudia; Piccinini, Giulia; Doneddu, Pietro E; Biscotti, Silvia; Padua, Luca

    2018-05-19

    Ulnar tunnel syndrome indicates ulnar neuropathy at different sites within the wrist. Several classifications of ulnar tunnel syndrome are present in literature, based upon typical nerve anatomy. However, anatomical variations are not uncommon and can complicate assessment. The etiology is also complex, due to the numerous potential causes of entrapment. Clinical examination, neurophysiological testing, and imaging are all used to support the diagnosis. At present, many therapeutic approaches are available, ranging from observation to surgical management. Although ulnar neuropathy at the wrist has undergone extensive prior study, unresolved questions on diagnosis and treatment remain. In the current paper, we review relevant literature and present the current knowledge on ulnar tunnel syndrome.

  17. Key Features of Research Portal for Stimulating Research in Institutions of Higher Technical Education

    ERIC Educational Resources Information Center

    Agarwal, Parul Dharmani; Kiran, Ravi; Verma, Anil Kumar

    2012-01-01

    Problem Statement: The current higher learning institutions in developed countries have adapted to their changing role in a knowledge-based society It is time for developing countries like India to focus on Knowledge Management thus, the current study presents research undertaken in understanding the implication of Knowledge Management in the…

  18. Please Touch the Children: Appropriate Touch in the Primary Classroom

    ERIC Educational Resources Information Center

    Owen, Pamela M.; Gillentine, Jonathan

    2011-01-01

    This study proposes to shift the current theoretical framework in which teachers practise a guarded approach regarding the touching of children in early childhood settings, towards a practice of acceptance. A brief historical context of touching is presented and supplemented with a survey of 63 currently practising K-3rd grade teachers. The survey…

  19. A Synthesis of the Literature on Research Methods Education

    ERIC Educational Resources Information Center

    Earley, Mark A.

    2014-01-01

    The purpose of this research synthesis is to examine the current research on teaching and learning research methods. The aims are to understand the themes present in the current literature and identify gaps in our understanding of how we teach, and how students learn, research methods. A synthesis of 89 studies generated three themes: (1)…

  20. University Students' Causal Conceptions about Social Mobility: Diverging Pathways for Believers in Personal Merit and Luck

    ERIC Educational Resources Information Center

    Shane, Jacob; Heckhausen, Jutta

    2013-01-01

    Many college students hold ambitious goals for upward social mobility via post-college careers. However, in the current economic recession such optimistic expectations are not a given. The present study examines how college students' current social status and beliefs in causal factors for socioeconomic status (SES) attainment lead to diverging…

  1. Nuclear medicine in clinical urology and nephrology

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

    Tauxe, W.N.; Dubousky, E.V.

    This book presents explanations of current procedures involving the kidney with information of the performance of each test, its rationale, and interpretation. The information covers all currently used radiopharmaceuticals, radiation dosimetry, instrumentation, test protocols, and mathematical principles of pathophysiology as they relate to nuclear medicine studies. Information is provided on which radiopharmaceutical, instrument, or computer application to use, and when.

  2. Educational Technology Use among K-12 Teachers: What Technologies Are Available and What Barriers Are Present?

    ERIC Educational Resources Information Center

    Francom, Gregory M.

    2016-01-01

    In order to prepare teachers to integrate technology into teaching and learning activities, teacher educators and administrators need current information about the types of technologies available in classrooms. The current survey research study of K-12 public school teachers in a rural North Midwestern state provides updated information on…

  3. Extreme Consumption Drinking Gaming and Prepartying among High School Students

    ERIC Educational Resources Information Center

    Tomaso, Cara C.; Zamboanga, Byron L.; Haas, Amie L.; Kenney, Shannon R.; Ham, Lindsay S.; Borsari, Brian

    2016-01-01

    Drinking games and prepartying (i.e., drinking before going to a social gathering/event) have emerged as high-risk drinking behaviors in high school students. The present study examines the current prepartying behaviors of high school students who report current participation in extreme-consumption games (e.g., chugging) with those who do not.…

  4. Near-term probabilistic forecast of significant wildfire events for the Western United States

    Treesearch

    Haiganoush K. Preisler; Karin L. Riley; Crystal S. Stonesifer; Dave E. Calkin; Matt Jolly

    2016-01-01

    Fire danger and potential for large fires in the United States (US) is currently indicated via several forecasted qualitative indices. However, landscape-level quantitative forecasts of the probability of a large fire are currently lacking. In this study, we present a framework for forecasting large fire occurrence - an extreme value event - and evaluating...

  5. Gender, Prior Knowledge, Interest, and Experience in Electricity and Conceptual Change Text Manipulations in Learning about Direct Current.

    ERIC Educational Resources Information Center

    Chambers, Sharon K.; Andre, Thomas

    1997-01-01

    Presents a study that investigated relationships between gender, interest, and experience in electricity. Also explored the effect of conceptual change text manipulations on learning fundamental concepts of direct current. Suggests that conceptual change text manipulations are likely to be effective for both men and women. Contains 57 references.…

  6. Social Work Education. Coombe Lodge Report, Study Conference 74/208.

    ERIC Educational Resources Information Center

    Further Education Staff Coll., Blagdon (England).

    Papers presented on social work education in Britain include: Current developments in social work education (P.H. Young); selection of students (M. Elizabeth Edwards); the management of curriculum development (J. Snelling); the management of a social work department (M.J. McAllister); current issues and developments in social work training (D.C.G.…

  7. Distributed Attentional Deficits in Chronic Methamphetamine Abusers: Evidence from the Attentional Network Task (ANT)

    ERIC Educational Resources Information Center

    Salo, Ruth; Gabay, Shai; Fassbender, Catherine; Henik, Avishai

    2011-01-01

    Objective: The goal of the present study was to examine distributed attentional functions in long-term but currently abstinent methamphetamine (MA) abusers using a task that measures attentional alertness, orienting, and conflict resolution. Methods: Thirty currently abstinent MA abusers (1 month-5 years) and 22 healthy non-substance using adults…

  8. 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.

  9. Teaching and Learning English Functional Writing: Investigating Egyptian EFL Student Teachers' Currently-Needed Functional Writing Skills

    ERIC Educational Resources Information Center

    Abdallah, Mahmoud M. S.

    2014-01-01

    At an age marked by the emergence of new literacies, vast technological developments, and social networking practices, language is currently approached from a pragmatic perspective that recognises its functional use to meet realistic communicative goals. Taking this into account, the present study sought to identify the functional writing skills…

  10. Observations and modeling of the ionospheric gravity and diamagnetic current systems from CHAMP and Swarm measurements

    NASA Astrophysics Data System (ADS)

    Alken, P.

    2016-01-01

    The CHAMP and Swarm satellites, which provide high-quality magnetic field measurements in low-altitude polar orbits, are ideally suited for investigating ionospheric current systems. In this study, we focus on the F region low-latitude gravity and diamagnetic currents which are prominent in the equatorial ionization anomaly (EIA) region in the North and South Hemisphere. During its 10 year mission, CHAMP has sampled nearly the entire altitude range of the EIA, offering the opportunity to study these currents from above, inside, and below their source region. The Swarm constellation offers the unique opportunity to study near-simultaneous measurements of the current systems at different longitudinal separations. In this study, we present new observations of these current systems, investigate their seasonal and local time dependence, investigate the use of in situ electron density measurements as a proxy for the magnetic perturbations, and compute the longitudinal self correlation of these currents. We find that these currents are strongest during spring and fall, produce nighttime magnetic fields at satellite altitude of up to 5-7 nT during solar maximum, 2-3 nT during solar minimum, and are highly correlated with in situ electron density measurements. We also find these currents are self-correlated above 70% up to 15° longitude in both hemispheres during the evening.

  11. Intrinsic membrane properties of pre-oromotor neurons in the intermediate zone of the medullary reticular formation.

    PubMed

    Venugopal, S; Boulant, J A; Chen, Z; Travers, J B

    2010-06-16

    Neurons in the lower brainstem that control consummatory behavior are widely distributed in the reticular formation (RF) of the pons and medulla. The intrinsic membrane properties of neurons within this distributed system shape complex excitatory and inhibitory inputs from both orosensory and central structures implicated in homeostatic control to produce coordinated oromotor patterns. The current study explored the intrinsic membrane properties of neurons in the intermediate subdivision of the medullary reticular formation (IRt). Neurons in the IRt receive input from the overlying (gustatory) nucleus of the solitary tract and project to the oromotor nuclei. Recent behavioral pharmacology studies as well as computational modeling suggest that inhibition in the IRt plays an important role in the transition from a taste-initiated oromotor pattern of ingestion to one of rejection. The present study explored the impact of hyperpolarization on membrane properties. In response to depolarization, neurons responded with either a tonic discharge, an irregular/burst pattern or were spike-adaptive. A hyperpolarizing pre-pulse modulated the excitability of most (82%) IRt neurons to subsequent depolarization. Instances of both increased (30%) and decreased (52%) excitability were observed. Currents induced by the hyperpolarization included an outward 4-aminopyridine (4-AP) sensitive K+ current that suppressed excitability and an inward cation current that increased excitability. These currents are also present in other subpopulations of RF neurons that influence the oromotor nuclei and we discuss how these currents could alter firing characteristics to impact pattern generation. 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

  12. Transcranial Direct Current Stimulation Does Not Improve Language Outcome in Subacute Poststroke Aphasia.

    PubMed

    Spielmann, Kerstin; van de Sandt-Koenderman, W Mieke E; Heijenbrok-Kal, Majanka H; Ribbers, Gerard M

    2018-04-01

    The aim of the present study is to investigate the effect of transcranial direct current stimulation on word-finding treatment outcome in subacute poststroke aphasia. In this multi-center, double-blind, randomized controlled trial with 6-month follow-up, we included 58 patients with subacute aphasia (<3 months poststroke), who were enrolled in a stroke rehabilitation program. Patients participated in 2 separate intervention weeks. Each intervention week included 5 daily sessions of 45-minute word-finding therapy combined with either anodal transcranial direct current stimulation (1 mA, 20 minutes; experimental group) or sham transcranial direct current stimulation (control group) over the left inferior frontal gyrus. The primary outcome measure was the Boston Naming Test. Secondary outcome measures included naming performance for trained/untrained picture items and verbal communication. Both the experimental (n=26) and the control group (n=32) improved on the Boston Naming Test over the intervention period and 6-month follow-up; however, there were no significant differences between groups. Also for the secondary outcome measures, no significant differences were found. The results of the present study do not support an effect of transcranial direct current stimulation as an adjuvant treatment in subacute poststroke aphasia. URL: http://www.trialregister.nl/trialreg/admin/rctview.asp. Unique identifier: NTR4364. © 2018 American Heart Association, Inc.

  13. Modeling MHD Equilibrium and Dynamics with Non-Axisymmetric Resistive Walls in LTX and HBT-EP

    NASA Astrophysics Data System (ADS)

    Hansen, C.; Levesque, J.; Boyle, D. P.; Hughes, P.

    2017-10-01

    In experimental magnetized plasmas, currents in the first wall, vacuum vessel, and other conducting structures can have a strong influence on plasma shape and dynamics. These effects are complicated by the 3D nature of these structures, which dictate available current paths. Results from simulations to study the effect of external currents on plasmas in two different experiments will be presented: 1) The arbitrary geometry, 3D extended MHD code PSI-Tet is applied to study linear and non-linear plasma dynamics in the High Beta Tokamak (HBT-EP) focusing on toroidal asymmetries in the adjustable conducting wall. 2) Equilibrium reconstructions of the Lithium Tokamak eXperiment (LTX) in the presence of non-axisymmetric eddy currents. An axisymmetric model is used to reconstruct the plasma equilibrium, using the PSI-Tri code, along with a set of fixed 3D eddy current distributions in the first wall and vacuum vessel [C. Hansen et al., PoP Apr. 2017]. Simulations of detailed experimental geometries are enabled by use of the PSI-Tet code, which employs a high order finite element method on unstructured tetrahedral grids that are generated directly from CAD models. Further development of PSI-Tet and PSI-Tri will also be presented. This work supported by US DOE contract DE-SC0016256.

  14. Robotic assistants in personal care: A scoping review.

    PubMed

    Bilyea, A; Seth, N; Nesathurai, S; Abdullah, H A

    2017-11-01

    The aim of this study is to present an overview of the technological advances in the field of robotics developed for assistance with activities of daily living (ADL), and to present areas where further research is required. Four databases were searched for articles presenting either a novel design of one of these personal care robotic system or trial results relating to these systems. Articles presenting nine different robotic personal care systems were examined, six of which had been developed after 2005. These six also all have publications relating to their trials. In the majority of trials, patient independence was improved with operation of the robotic device for a specific subset of ADL. A map of the current state of the field of personal care robotics is presented in this study. Areas requiring further research include improving feedback and awareness, as well as refining control methods and pre-programmed behaviors. Developing an affordable, easy to use system would help fill the current gap in the commercial market. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

  15. Transient sodium current at subthreshold voltages: activation by EPSP waveforms

    PubMed Central

    Carter, Brett C.; Giessel, Andrew J.; Sabatini, Bernardo L.; Bean, Bruce P.

    2012-01-01

    Summary Tetrodotoxin (TTX)-sensitive sodium channels carry large transient currents during action potentials and also “persistent” sodium current, a non-inactivating TTX-sensitive current present at subthreshold voltages. We examined gating of subthreshold sodium current in dissociated cerebellar Purkinje neurons and hippocampal CA1 neurons, studied at 37 °C with near-physiological ionic conditions. Unexpectedly, in both cell types small voltage steps at subthreshold voltages activated a substantial component of transient sodium current as well as persistent current. Subthreshold EPSP-like waveforms also activated a large component of transient sodium current, but IPSP-like waveforms engaged primarily persistent sodium current with only a small additional transient component. Activation of transient as well as persistent sodium current at subthreshold voltages produces amplification of EPSPs that is sensitive to the rate of depolarization and can help account for the dependence of spike threshold on depolarization rate, as previously observed in vivo. PMID:22998875

  16. Ring Current Dynamics in Moderate and Strong Storms: Comparative Analysis of TWINS and IMAGE/HENA Data with the Comprehensive Ring Current Model

    NASA Technical Reports Server (NTRS)

    Buzulukova, N.; Fok, M.-C.; Goldstein, J.; Valek, P.; McComas, D. J.; Brandt, P. C.

    2010-01-01

    We present a comparative study of ring current dynamics during strong and moderate storms. The ring current during the strong storm is studied with IMAGE/HENA data near the solar cycle maximum in 2000. The ring current during the moderate storm is studied using energetic neutral atom (ENA) data from the Two Wide-Angle Imaging Neutral- Atom Spectrometers (TWINS) mission during the solar minimum in 2008. For both storms, the local time distributions of ENA emissions show signatures of postmidnight enhancement (PME) during the main phases. To model the ring current and ENA emissions, we use the Comprehensive Ring Current Model (CRCM). CRCM results show that the main-phase ring current pressure peaks in the premidnight-dusk sector, while the most intense CRCM-simulated ENA emissions show PME signatures. We analyze two factors to explain this difference: the dependence of charge-exchange cross section on energy and pitch angle distributions of ring current. We find that the IMF By effect (twisting of the convection pattern due to By) is not needed to form the PME. Additionally, the PME is more pronounced for the strong storm, although relative shielding and hence electric field skewing is well developed for both events.

  17. A Review of Current Investigations of Urban-Induced Rainfall and Recommendations for the Future

    NASA Technical Reports Server (NTRS)

    Shepherd, J. Marshall

    2004-01-01

    Precipitation is a key link in the global water cycle and a proxy for changing climate; therefore proper assessment of the urban environment s impact on precipitation (land use, aerosols, thermal properties) will be increasingly important in ongoing climate diagnostics and prediction, Global Water and Energy Cycle (GWEC) analysis and modeling, weather forecasting, freshwater resource management, urban planning-design and land-atmosphere-ocean interface processes. These facts are particularly critical if current projections for global urban growth are accurate. The goal of this paper is to provide a concise review of recent (1990-present) studies related to how the urban environment affects precipitation. In addition to providing a synopsis of current work, recent findings are placed in context with historical investigations such as METROMEX studies. Both observational and modeling studies of urban-induced rainfall are discussed. Additionally, a discussion of the relative roles of urban dynamic and microphysical (e.g. aerosol) processes is presented. The paper closes with a set of recommendations for what observations and capabilities are needed in the future to advance our understanding of the processes.

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

    Jiang, Zhenyu, E-mail: jiangzhenyu1201@hotmail.com, E-mail: jianxu@engr.psu.edu; Liu, Yan; Mo, Chen

    In an attempt to suppress the dark current, the barrier layer engineer for solution-processed PbSe colloidal quantum-dot (CQD) photodetectors has been investigated in the present study. It was found that the dark current can be significantly suppressed by implementing two types of carrier blocking layers, namely, hole blocking layer and electron blocking layer, sandwiched in between two active PbSe CQD layers. Meanwhile no adverse impact has been observed for the photo current. Our study suggests that this improvement resides on the transport pathway created via carrier recombination at intermediate layer, which provides wide implications for the suppression of dark currentmore » for infrared photodetectors.« less

  19. Theoretical study of the effect of ionospheric return currents on the electron temperature

    NASA Technical Reports Server (NTRS)

    Schunk, R. W.; Sojka, J. J.; Bowline, M. D.

    1987-01-01

    A time-dependent, three-dimensional model of the high-altitude ionosphere is presently used to study the effects of field-aligned ionospheric return currents on auroral electron temperatures for different seasonal and solar cycle conditions, as well as for different upper boundary heat fluxes. The average, large scale, return current densities, which are a few microamps/sq m, are too small to affect auroral electron temperatures. The thermoelectric effect exhibits a pronounced solar cycle and seasonal dependence, and its heat transport corresponds to an upward flow of electron energy which can be either a source or sink of electron energy depending on altitude and geophysical conditions.

  20. Intensity coding in electric hearing: effects of electrode configurations and stimulation waveforms.

    PubMed

    Chua, Tiffany Elise H; Bachman, Mark; Zeng, Fan-Gang

    2011-01-01

    Current cochlear implants typically stimulate the auditory nerve with biphasic pulses and monopolar electrode configurations. Tripolar stimulation can increase spatial selectivity and potentially improve place pitch related perception but requires higher current levels to elicit the same loudness as monopolar stimulation. The present study combined delayed pseudomonophonasic pulses, which produce lower thresholds, with tripolar stimulation in an attempt to solve the power-performance tradeoff problem. The present study systematically measured thresholds, dynamic range, loudness growth, and intensity discrimination using either biphasic or delayed pseudomonophonasic pulses under both monopolar and tripolar stimulation. Participants were five Clarion cochlear implant users. For each subject, data from apical, middle, and basal electrode positions were collected when possible. Compared with biphasic pulses, delayed pseudomonophonasic pulses increased the dynamic range by lowering thresholds while maintaining comparable maximum allowable levels under both electrode configurations. However, delayed pseudomonophonasic pulses did not change the shape of loudness growth function and actually increased intensity discrimination limens, especially at lower current levels. The present results indicate that delayed pseudomonophonasic pulses coupled with tripolar stimulation cannot provide significant power savings nor can it increase the functional dynamic range. Whether this combined stimulation could improve functional spectral resolution remains to be seen.

  1. Differential diagnosis and treatment of bilateral facial pain after whiplash: a case report.

    PubMed

    Peterson, Seth

    2015-01-01

    Clinical case report. Symptoms in the face and jaw are common after whiplash. Few studies have reported cervicogenic headache in a trigeminal nerve distribution, and no published studies could be found describing such symptoms experienced bilaterally after whiplash. The objective of the current case report was to detail the clinical reasoning and management of an uncommon patient presentation. The 41-year-old female patient of the current case complained of shooting pain in the jaw, cheek and forehead beginning 7 days after her accident. No imaging was performed, and examination ruled out serious pathology. The patient was treated primarily with deep neck flexor (DNF) and proprioceptive training for 10 visits over an 8-week period. The Numeric Pain Rating Scale improved from 2/10 to 0/10, the Neck Disability Index improved from 17/50 to 1/50, and the Neck Flexor Muscle Endurance Test improved from 13 to 30 s. The patient remained symptom-free at 4-month follow-up. The current case report describes a patient presentation unique to the literature. Significant changes were seen by week 3 with DNF and proprioceptive training. Additional research is required to determine the effectiveness of this intervention in similar presentations.

  2. Precision Medicine in Gastrointestinal Pathology.

    PubMed

    Wang, David H; Park, Jason Y

    2016-05-01

    -Precision medicine is the promise of individualized therapy and management of patients based on their personal biology. There are now multiple global initiatives to perform whole-genome sequencing on millions of individuals. In the United States, an early program was the Million Veteran Program, and a more recent proposal in 2015 by the president of the United States is the Precision Medicine Initiative. To implement precision medicine in routine oncology care, genetic variants present in tumors need to be matched with effective clinical therapeutics. When we focus on the current state of precision medicine for gastrointestinal malignancies, it becomes apparent that there is a mixed history of success and failure. -To present the current state of precision medicine using gastrointestinal oncology as a model. We will present currently available targeted therapeutics, promising new findings in clinical genomic oncology, remaining quality issues in genomic testing, and emerging oncology clinical trial designs. -Review of the literature including clinical genomic studies on gastrointestinal malignancies, clinical oncology trials on therapeutics targeted to molecular alterations, and emerging clinical oncology study designs. -Translating our ability to sequence thousands of genes into meaningful improvements in patient survival will be the challenge for the next decade.

  3. Environmental Impact of Asbestos Cement Pipe Renewal Technologies (WaterRF Report 4465)

    EPA Science Inventory

    This report summarizes asbestos regulations within the United States and presents current utility practices for a select number of utilities in North America and Australia. In addition, two real-world renewal demonstrations are presented as case studies examining the impact of pi...

  4. Generation of mechanical vibrations in metal samples by the use of the pinch effect

    NASA Astrophysics Data System (ADS)

    Troitskiy, O. A.; Skvortsov, O. B.; Stashenko, V. I.

    2017-07-01

    The article presents the recent research in electrodynamic processes for metal samples exposed to current pulses. The pinch effect and the skin effect cause the vibration of the metal rods. The results of these studies show how current and magnetic field interact with material samples of gold, silver and copper. The analysis allowed establishing the dependences of peak acceleration on current density and conductor diameter. The dependencies can be used in metal workings and for nondestructive testing.

  5. 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.

  6. Role of varying interface conditions on the eddy current response from cracks in multilayer structures

    NASA Astrophysics Data System (ADS)

    Cherry, Aaron; Knopp, Jeremy; Aldrin, John C.; Sabbagh, Harold A.; Boehnlein, Thomas; Mooers, Ryan

    2013-01-01

    There is a need to improve the understanding of the role of interface conditions on eddy current inspections for cracks in multilayer aircraft structures. This paper presents initial experimental and simulated results studying the influence of gaps and contact conditions between two plates with a notch in the second layer. Simulations show an amplification of the eddy current signal for a subsurface notch adjacent to an air gap as opposed to a submerged notch in a solid plate.

  7. Modeling of Photoionized Plasmas

    NASA Technical Reports Server (NTRS)

    Kallman, Timothy R.

    2010-01-01

    In this paper I review the motivation and current status of modeling of plasmas exposed to strong radiation fields, as it applies to the study of cosmic X-ray sources. This includes some of the astrophysical issues which can be addressed, the ingredients for the models, the current computational tools, the limitations imposed by currently available atomic data, and the validity of some of the standard assumptions. I will also discuss ideas for the future: challenges associated with future missions, opportunities presented by improved computers, and goals for atomic data collection.

  8. Cerebellar transcranial direct current stimulation in patients with ataxia: A double-blind, randomized, sham-controlled study.

    PubMed

    Benussi, Alberto; Koch, Giacomo; Cotelli, Maria; Padovani, Alessandro; Borroni, Barbara

    2015-10-01

    Numerous studies have highlighted the possibility of modulating the excitability of cerebellar circuits using transcranial direct current stimulation. The present study investigated whether a single session of cerebellar anodal transcranial direct current stimulation could improve symptoms in patients with ataxia. Nineteen patients with ataxia underwent a clinical and functional evaluation pre- and post-double-blind, randomized, sham, or anodal transcranial direct current stimulation. There was a significant interaction between treatment and time on the Scale for the Assessment and Rating of Ataxia, on the International Cooperative Ataxia Rating Scale, on the 9-Hole Peg Test, and on the 8-Meter Walking Time (P < 0.001). At the end of the sessions, all performance scores were significantly different in the sham trial, compared to the intervention trial. A single session of anodal cerebellar transcranial direct current stimulation can transiently improve symptoms in patients with ataxia and might represent a promising tool for future rehabilitative approaches. © 2015 International Parkinson and Movement Disorder Society.

  9. Social Studies Teacher Candidates' Views on Historical Thinking Skills

    ERIC Educational Resources Information Center

    Ozmen, Cengiz

    2015-01-01

    Current study aimed to present Social Studies teacher candidates' views on historical thinking skills. Study was conducted using qualitative design and working group was composed of a total of 121 teacher candidates (62 females and 59 males) attending Social Studies Teaching Department of Karadeniz Technical University and Adiyaman University…

  10. Marijuana and actual driving performance

    DOT National Transportation Integrated Search

    1993-11-01

    This report concerns the effects of marijuana smoking on actual driving performance. It presents the results of one pilot and three actual driving studies. The pilot study's major purpose was to establish the THC dose current marijuana users smoke to...

  11. The U.S. Armored Brigade Combat Team Versus Current Hybrid Threat: How Should the U.S. ABCT be Organized and Equipped to Address the Current Hybrid Threat

    DTIC Science & Technology

    2017-06-09

    analysis method and focus on analyzing available documents while studying the separate but similar cases of Israel fighting Hezbollah in Lebanon and...two significant case studies will be reviewed. One deals with the conflict between Hezbollah and Israel Defense Forces (IDF) in Israel and Lebanon...Vietnam and in Operation Iraqi Freedom. Captain Houvinen in his research presented a case study from the Second Lebanon War based on the U.S. experience

  12. The influence of negative current collector size on a liquid metal positive electrode

    NASA Astrophysics Data System (ADS)

    Mohammad, Ibrahim; Ashour, Rakan; Kelley, Douglas

    2017-11-01

    Fluid mixing in the positive electrode of a liquid metal battery (LMB) governs some performance-related factors such as the rate of charge and discharge of the battery. The negative current collector (NCC) of a LMB is always smaller than the positive current collector, implying that current is convergent at the NCC. Also, different NCC sizes introduce different thermal, electromagnetic, and flow boundary conditions. In this talk, I will show how our lab studies the influence of NCC diameter on the flow in a liquid metal positive electrode driven by electrical current. I will present measurements of the flow velocity taken via Ultrasonic Doppler Velocimetry (UDV) over a range of different currents, at different NCC diameters.

  13. Direct Current Contamination of Kilohertz Frequency Alternating Current Waveforms

    PubMed Central

    Franke, Manfred; Bhadra, Niloy; Bhadra, Narendra; Kilgore, Kevin

    2014-01-01

    Kilohertz Frequency Alternating Current (KHFAC) waveforms are being evaluated in a variety of physiological settings because of their potential to modulate neural activity uniquely when compared to frequencies in the sub-kilohertz range. However, the use of waveforms in this frequency range presents some unique challenges regarding the generator output. In this study we explored the possibility of undesirable contamination of the KHFAC waveforms by direct current (DC). We evaluated current- and voltage-controlled KHFAC waveform generators in configurations that included a capacitive coupling between generator and electrode, a resistive coupling and combinations of capacitive with inductive coupling. Our results demonstrate that both voltage- and current-controlled signal generators can unintentionally add DC-contamination to a KHFAC signal, and that capacitive coupling is not always sufficient to eliminate this contamination. We furthermore demonstrated that high value inductors, placed in parallel with the electrode, can be effective in eliminating DC-contamination irrespective of the type of stimulator, reducing the DC contamination to less than 1 μA. This study highlights the importance of carefully designing the electronic setup used in KHFAC studies and suggests specific testing that should be performed and reported in all studies that assess the neural response to KHFAC waveforms. PMID:24820914

  14. The current evidence base for the feasibility of 48-hour continuous subcutaneous infusions (CSCIs): A systematically-structured review.

    PubMed

    Baker, James; Dickman, Andrew; Mason, Stephen; Ellershaw, John

    2018-01-01

    A continuous subcutaneous infusion (CSCI) is an effective method of multiple drug administration commonly encountered in end of life care when the oral route is compromised. At present, current practice is to limit syringe driver infusion time to a maximum of 24 hours as dictated by available chemical stability data. However, the ability to deliver prescribed medication by a CSCI over 48 hours may have numerous benefits in both patient care and health service resource utilisation. To examine and present the current evidence base for the stability of 48-hour multiple-drug CSCIs in current clinical practice. A systematically-structured review following PRISMA guidelines. Three electronic databases and the grey literature were searched with no time limits. Empirical studies reporting data on the chemical stability of continuous subcutaneous infusions or solutions stored in polypropylene syringes were included. Twenty-one empirical studies were included in this review reporting chemical compatibility and stability of 32 discrete combinations of twenty-four drugs tested at a variety of different drug concentrations. The majority of combinations reported were assessed as being chemically compatible. The greatest risk of clinically significant chemical degradation was observed with midazolam. Only one study reported the microbiological stability of the solution examined. There is currently limited evidence for the physical, chemical and microbiological stability of solutions for continuous subcutaneous infusion over a period of 48 hours. More stability data is required before the use of 48-hour CSCIs can be evaluated for use within clinical practice.

  15. Electrochemical production and use of free chlorine for pollutant removal: an experimental design approach.

    PubMed

    Antonelli, Raissa; de Araújo, Karla Santos; Pires, Ricardo Francisco; Fornazari, Ana Luiza de Toledo; Granato, Ana Claudia; Malpass, Geoffroy Roger Pointer

    2017-10-28

    The present paper presents the study of (1) the optimization of electrochemical-free chlorine production using an experimental design approach, and (2) the application of the optimum conditions obtained for the application in photo-assisted electrochemical degradation of simulated textile effluent. In the experimental design the influence of inter-electrode gap, pH, NaCl concentration and current was considered. It was observed that the four variables studied are significant for the process, with NaCl concentration and current being the most significant variables for free chlorine production. The maximum free chlorine production was obtained at a current of 2.33 A and NaCl concentrations in 0.96 mol dm -3 . The application of the optimized conditions with simultaneous UV irradiation resulted in up to 83.1% Total Organic Carbon removal and 100% of colour removal over 180 min of electrolysis. The results indicate that a systematic (statistical) approach to the electrochemical treatment of pollutants can save time and reagents.

  16. Tunable Universal Filter with Current Follower and Transconductance Amplifiers and Study of Parasitic Influences

    NASA Astrophysics Data System (ADS)

    Jeřábek, Jan; Šotner, Roman; Vrba, Kamil

    2011-11-01

    A universal filter with dual-output current follower (DO-CF), two transconductance amplifiers (OTAs) and two passive elements is presented in this paper. The filter is tunable, of the single-input multiple-output (SIMO) type, and operates in the current mode. Our solution utilizes a low-impedance input node and high-impedance outputs. All types of the active elements used can be realized using our UCC-N1B 0520 integrated circuit and therefore the paper contains not only simulation results that were obtained with the help of behavioral model of the UCC-N1B 0520 element, but also the characteristics that were gained by measurement with the mentioned circuit. The presented simulation and measurement results prove the quality of designed filter. Similar multi-loop structures are very-well known, but there are some drawbacks that are not discussed in similar papers. This paper also contains detailed study of parasitic influences on the filter performance.

  17. Reactor Physics Scoping and Characterization Study on Implementation of TRIGA Fuel in the Advanced Test Reactor

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

    Jennifer Lyons; Wade R. Marcum; Mark D. DeHart

    2014-01-01

    The Advanced Test Reactor (ATR), under the Reduced Enrichment for Research and Test Reactors (RERTR) Program and the Global Threat Reduction Initiative (GTRI), is conducting feasibility studies for the conversion of its fuel from a highly enriched uranium (HEU) composition to a low enriched uranium (LEU) composition. These studies have considered a wide variety of LEU plate-type fuels to replace the current HEU fuel. Continuing to investigate potential alternatives to the present HEU fuel form, this study presents a preliminary analysis of TRIGA® fuel within the current ATR fuel envelopes and compares it to the functional requirements delineated by themore » Naval Reactors Program, which includes: greater than 4.8E+14 fissions/s/g of 235U, a fast to thermal neutron flux ratio that is less than 5% deviation of its current value, a constant cycle power within the corner lobes, and an operational cycle length of 56 days at 120 MW. Other parameters outside those put forth by the Naval Reactors Program which are investigated herein include axial and radial power profiles, effective delayed neutron fraction, and mean neutron generation time.« less

  18. The Acquisition of the Copula "Be" in Present Simple Tense in English by Native Speakers of Russian

    ERIC Educational Resources Information Center

    Unlu, Elena Antonova; Hatipoglu, Ciler

    2012-01-01

    The current research investigated the acquisition of the copula "be" in Present Simple Tense (PST) in English by native speakers of Russian. The aim of the study was to determine whether or not Russian students with different levels of English proficiency would encounter any problems while using the copula "be" in PST in English. The study also…

  19. Bioelectrical Impedance and The Frequency Dependent Current Conduction Through Biological Tissues: A Short Review

    NASA Astrophysics Data System (ADS)

    Kanti Bera, Tushar

    2018-03-01

    Biological tissues are developed with biological cells which exhibit complex electrical impedance called electrical bioimpedance. Under an alternating electrical excitation the bioimpedance varies with the tissue anatomy, composition and the signal frequency. The current penetration and conduction paths vary with frequency of the applied signal. Bioimpedance spectroscopy is used to study the frequency response of the electrical impedance of biological materials noninvasively. In bioimpedance spectroscopy, a low amplitude electrical signal is injected to the tissue sample or body parts to characterization the sample in terms of its bioimpedance. The electrical current conduction phenomena, which is highly influenced by the tissue impedance and the signal frequency, is an important phenomena which should be studied to understand the bioimpedance techniques like bioelectrical impedance analysis (BIA), EIS, or else. In this paper the origin of bioelectrical impedance and current conduction phenomena has been reviewed to present a brief summary of bioelectrical impedance and the frequency dependent current conduction through biological tissues. Simulation studies are conducted with alternation current injection through a two dimensional model of biological tissues containing finite number of biological cells suspended in extracellular fluid. The paper demonstrates the simulation of alternating current conduction through biological tissues conducted by COMSOL Multiphysics. Simulation studies also show the frequency response of the tissue impedance for different tissue compositions.

  20. Performances and first science results with the VEGA/CHARA visible instrument

    NASA Astrophysics Data System (ADS)

    Mourard, D.; Tallon, M.; Bério, Ph.; Bonneau, D.; Chesneau, O.; Clausse, J. M.; Delaa, O.; Nardetto, N.; Perraut, K.; Spang, A.; Stee, Ph.; Tallon-Bosc, I.; McAlister, H.; ten Brummelaar, T.; Sturmann, J.; Sturmann, L.; Turner, N.; Farrington, C.; Goldfinger, P. J.

    2010-07-01

    This paper presents the current status of the VEGA (Visible spEctroGraph and polArimeter) instrument installed at the coherent focus of the CHARA Array, Mount Wilson CA. Installed in september 2007, the first science programs have started during summer 2008 and first science results are now published. Dedicated to high angular (0.3mas) and high spectral (R=30000) astrophysical studies, VEGA main objectives are the study of circumstellar environments of hot active stars or interactive binary systems and a large palette of new programs dedicated to fundamental stellar parameters. We will present successively the main characteristics of the instrument and its current performances in the CHARA environment, a short summary of two science programs and finally we will develop some studies showing the potential and difficulties of the 3 telescopes mode of VEGA/CHARA.

  1. Holocaust cancer patients: a comparative study.

    PubMed

    Baider, L; Peretz, T; De-Nour, A K

    1993-11-01

    There is as yet no consensus on the long-term effects of severe life-threatening stresses. In an earlier study (Baider et al. 1992), we gained some understanding of this issue by addressing a specific question: How do individuals who have undergone severe stress in the past cope with a current stress? We investigated whether severe stress occurring in the past had a long-term effect on present coping capabilities. We addressed the question by studying a group of Holocaust survivors (severe past stress) who were diagnosed as having cancer (current stress) and compared them to a matched group of cancer patients with no past history of trauma. The matching was done on most demographic variables (gender, age, marital status, and education), as well as on disease variables (site and stage of cancer, time since cancer diagnosis, previous and present treatments). The results were unequivocal.

  2. Effects of obliquely opposing and following currents on wave propagation in a new 3D wave-current basin

    NASA Astrophysics Data System (ADS)

    Lieske, Mike; Schlurmann, Torsten

    2016-04-01

    INTRODUCTION & MOTIVATION The design of structures in coastal and offshore areas and their maintenance are key components of coastal protection. Usually, assessments of processes and loads on coastal structures are derived from experiments with flow and wave parameters in separate physical models. However, Peregrin (1976) already points out that processes in natural shallow coastal waters flow and sea state processes do not occur separately, but influence each other nonlinearly. Kemp & Simons (1982) perform 2D laboratory tests and study the interactions between a turbulent flow and following waves. They highlight the significance of wave-induced changes in the current properties, especially in the mean flow profiles, and draw attention to turbulent fluctuations and bottom shear stresses. Kemp & Simons (1983) also study these processes and features with opposing waves. Studies on the wave-current interaction in three-dimensional space for a certain wave height, wave period and water depth were conducted by MacIver et al. (2006). The research focus is set on the investigation of long-crested waves on obliquely opposing and following currents in the new 3D wave-current basin. METHODOLOGY In a first step the flow analysis without waves is carried out and includes measurements of flow profiles in the sweet spot of the basin at predefined measurement positions. Five measuring points in the water column have been delineated in different water depths in order to obtain vertical flow profiles. For the characterization of the undisturbed flow properties in the basin, an uniformly distributed flow was generated in the wave basin. In the second step wave analysis without current, the unidirectional wave propagation and wave height were investigated for long-crested waves in intermediate wave conditions. In the sweet spot of the wave basin waves with three different wave directions, three wave periods and uniform wave steepness were examined. For evaluation, we applied a common 3D wave analysis method, the Bayesian Directional Spectrum method (BDM). BDM was presented by Hashimoto et al. (1988). Lastly, identification of the wave-current interaction, the results from experiment with simultaneous waves and currents are compared with results for only-currents and only-waves in order to identify and exemplify the significance of nonlinear interaction processes. RESULTS The first results of the wave-current interaction show, as expected, a reduction in the wave height in the direction of flow and an increase in wave heights against the flow with unidirectional monochromatic waves. The superposition of current and orbital velocities cannot be conducted linearly. Furthermore, the results show a current domination for low wave periods and wave domination for larger wave periods. The criterion of a current or wave domination will be presented in the presentation. ACKNOWLEDGEMENT The support of the KFKI research project "Seegangsbelastungen (Seele)" (Contract No. 03KIS107) by the German "Federal Ministry of Education and Research (BMBF)" is gratefully acknowledged.

  3. Boxwood Borer Heterobostrychus brunneus (Coleoptera: Bostrichidae) Infesting Dried Cassava: A Current Record from Southern Ethiopia

    PubMed Central

    Parmar, Aditya; Kirchner, Sascha M.; Langguth, Henning; Döring, Thomas F.; Hensel, Oliver

    2017-01-01

    Insect specimens of adult beetles and larvae of 7–9 and 9–10 mm length, respectively were collected from infested dry cassava at two locations from multiple stores in southern Ethiopia. The specimens were identified as Heterobostrychus brunneus (Murray, 1867) commonly known as boxwood borer and auger beetle. The study presents a current record of H. brunneus in Ethiopia, particularly in the context of infesting food products. Additionally, a wide geographical distribution of the pest was reviewed and presented in this article. Current evidence suggests that H. brunneus is a serious pest of forest wood, structural timbers, and dried food products and that it carries a risk to be introduced into various other parts of the world via global trade. PMID:28130456

  4. Domain wall dynamics driven by spin transfer torque and the spin-orbit field.

    PubMed

    Hayashi, Masamitsu; Nakatani, Yoshinobu; Fukami, Shunsuke; Yamanouchi, Michihiko; Mitani, Seiji; Ohno, Hideo

    2012-01-18

    We have studied current-driven dynamics of domain walls when an in-plane magnetic field is present in perpendicularly magnetized nanowires using an analytical model and micromagnetic simulations. We model an experimentally studied system, ultrathin magnetic nanowires with perpendicular anisotropy, where an effective in-plane magnetic field is developed when current is passed along the nanowire due to the Rashba-like spin-orbit coupling. Using a one-dimensional model of a domain wall together with micromagnetic simulations, we show that the existence of such in-plane magnetic fields can either lower or raise the threshold current needed to cause domain wall motion. In the presence of the in-plane field, the threshold current differs for positive and negative currents for a given wall chirality, and the wall motion becomes sensitive to out-of-plane magnetic fields. We show that large non-adiabatic spin torque can counteract the effect of the in-plane field.

  5. Heavy doping effects in high efficiency silicon solar cells

    NASA Technical Reports Server (NTRS)

    Lindholm, F. A.; Neugroschel, A.

    1985-01-01

    The use of a (silicon)/(heavily doped polysilicon)/(metal) structure to replace the conventional high-low junction (or back-surface-field, BSF) structure of silicon solar cells was examined. The results of an experimental study designed to explore both qualitatively and quantitatively the mechanism of the improved current gain in bipolar transistors with polysilicon emitter contact are presented. A reciprocity theorem is presented that relates the short circuit current of a device, induced by a carrier generation source, to the minority carrier Fermi level in the dark. A method for accurate measurement of minority-carrier diffusion coefficients in silicon is described.

  6. Asymmetrical booster ascent guidance and control system design study. Volume 5: Space shuttle powered explicit guidance. [space shuttle development

    NASA Technical Reports Server (NTRS)

    Jaggers, R. F.

    1974-01-01

    An optimum powered explicit guidance algorithm capable of handling all space shuttle exoatospheric maneuvers is presented. The theoretical and practical basis for the currently baselined space shuttle powered flight guidance equations and logic is documented. Detailed flow diagrams for implementing the steering computations for all shuttle phases, including powered return to launch site (RTLS) abort, are also presented. Derivation of the powered RTLS algorithm is provided, as well as detailed flow diagrams for implementing the option. The flow diagrams and equations are compatible with the current powered flight documentation.

  7. Omental fibromatosis treated by laparoscopic wide surgical resection.

    PubMed

    Martin, David; Muradbegovic, Mirza; Andrejevic-Blant, Snezana; Petermann, David; Di Mare, Luca

    2018-02-01

    The current report presents a case of an omental fibromatosis discovered incidentally in a 46-year-old woman with no particular medical history and few symptoms. A surgical biopsy was performed initially, and microscopic examination revealed myofibroblastic proliferation. After additional immunohistochemical and molecular analyses, omental fibromatosis was diagnosed. Omental fibromatosis, also called intra-abdominal desmoid, is a rare and benign tumour but can be locally aggressive. Majority of cases are asymptomatic, and difficult to diagnose based on clinical presentation and radiological investigation. Final diagnosis is usually made on histopathology and immunohistochemistry studies. Surgical wide excision is currently the treatment of choice.

  8. [A historical-epistemological perspective of the ontological problem of Positivism. Positivism and psychiatry].

    PubMed

    Fantin, Juan Carlos

    2005-01-01

    The present article reviews epistemological problems related to the philosophical and scientific current known as Positivism. The revision begins with the study of the historical period during which the Logical Positivism emerges (early in the decade of 1920); and finishes with the analysis of its influence on psychiatry and its relation with other epistemological currents in the same period. The article reviews the historical and epistemological outlook at te beginning of the XX th century, when the problem of language became ontologically outstanding. The question of language remains important in the present discussions.

  9. Smoke inhalation among firefighters.

    PubMed

    Bizovi, K E; Leikin, J D

    1995-01-01

    Smoke inhalation may account for up to 75% of fire-related deaths and presents with a wide variety of complaints and findings. The authors examine the components of smoke to illustrate the patterns of smoke injury, provide useful guidelines on evaluation and management, survey current laboratory and diagnostic studies, and present their recommendations for treatment.

  10. Navigation Assistance: A Trade-Off between Wayfinding Support and Configural Learning Support

    ERIC Educational Resources Information Center

    Munzer, Stefan; Zimmer, Hubert D.; Baus, Jorg

    2012-01-01

    Current GPS-based mobile navigation assistance systems support wayfinding, but they do not support learning about the spatial configuration of an environment. The present study examined effects of visual presentation modes for navigation assistance on wayfinding accuracy, route learning, and configural learning. Participants (high-school students)…

  11. Nondestructive Testing Magnetic Particle RQA/M1-5330.11.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Huntsville, AL. George C. Marshall Space Flight Center.

    As one in the series of programmed instruction handbooks, prepared by the U. S. space program, home study material is presented in this volume concerning familiarization and orientation on magnetic particle properties. The subject is presented under the following headings: Magnetism, Producing a Magnetic Field, Magnetizing Currents, Materials and…

  12. Comprehension of Architectural Construction through Multimedia Active Learning

    ERIC Educational Resources Information Center

    Mas, Ángeles; Blasco, Vicente; Lerma, Carlos; Angulo, Quiteria

    2013-01-01

    This study presents an investigation about the use of multimedia procedures applied to architectural construction teaching. We have applied current technological resources, aiming to rationalize and optimize the active learning process. The experience presented to students is very simple and yet very effective. It has consisted in a simulation of…

  13. ARSENIC BIOAVAILABILITY ASSOCIATED WITH THE PRESENCE OF CCA-TREATED WOOD PRODUCTS

    EPA Science Inventory

    This is an invited paper/slide presentation to be presented by Dr. Karen Bradham at the 8th International Conference on the Biogeochemistry of Trace Elements, Adelaide, Australia, April 3 - 7, 2005. The PowerPoint slides describe the study design of projects currently being perf...

  14. Current Issues in Maternal and Paternal Deprivation. Unit for Child Studies Selected Papers Number 6.

    ERIC Educational Resources Information Center

    Phillips, Shelley

    An overview of some major current issues in maternal and paternal deprivation is presented. Parts I and II focus on (1) single parents and issues in paternal deprivation and (2) sex stereotyping and issues in maternal deprivation, respectively. More particularly, Part I discusses the effects of divorce and death on children and the problem of…

  15. About plasma points' generation in Z-pinch

    NASA Astrophysics Data System (ADS)

    Afonin, V. I.; Potapov, A. V.; Lazarchuk, V. P.; Murugov, V. M.; Senik, A. V.

    1997-05-01

    The streak tube study results (at visible and x-ray ranges) of dynamics of fast Z-pinch formed at explosion of metal wire in diode of high current generator are presented. Amplitude of current in the load reached ˜180 kA at increase time ˜50 ns. The results' analysis points to capability of controlling hot plasma points generation process in Z-pinch.

  16. Effects of Transcranial Direct Current Stimulation (tDCS) on Behaviour and Electrophysiology of Language Production

    ERIC Educational Resources Information Center

    Wirth, Miranka; Rahman, Rasha Abdel; Kuenecke, Janina; Koenig, Thomas; Horn, Helge; Sommer, Werner; Dierks, Thomas

    2011-01-01

    Excitatory anodal transcranial direct current stimulation (A-tDCS) over the left dorsal prefrontal cortex (DPFC) has been shown to improve language production. The present study examined neurophysiological underpinnings of this effect. In a single-blinded within-subject design, we traced effects of A-tDCS compared to sham stimulation over the left…

  17. On the Mechanism of Maintenance and Instability of the Overvoltage Low-Pressure Discharge Forming a High-Current Runaway Electron Beam

    NASA Astrophysics Data System (ADS)

    Akishev, Yu. S.; Balakirev, A. A.; Karal'nik, V. B.; Medvedev, M. A.; Petryakov, A. V.; Trushkin, N. I.; Shafikov, A. G.

    2017-12-01

    Results of experiments on the study of dynamics of an overvoltage discharge at the low pressure p = 0.5-2.5 Torr up to its transition to the high-current low-voltage regime are presented, and the instability mechanism leading to a sharp voltage drop across the discharge is suggested.

  18. [Play therapy in hospital].

    PubMed

    Gold, Katharina; Grothues, Dirk; Leitzmann, Michael; Gruber, Hans; Melter, Michael

    2012-01-01

    The following article presents an overview of current research studies on play therapy in the hospital. It highlights individual diagnoses for which play therapy has shown reasonable success. The aim of this review is to describe the current status of the scientific debate on play therapy for sick children in order to allow conclusions regarding the indications for which play therapy is or might be useful.

  19. Anticipated Guilt as Behavioral Motivation: An Examination of Appeals to Help Unknown Others through Bone Marrow Donation

    ERIC Educational Resources Information Center

    Lindsey, Lisa L. Massi

    2005-01-01

    The current study posits that messages used to elicit behaviors to help unknown others must present substantial perceptions of a threat and efficacy to be successful. Given that many prosocial helping messages depict a threat to unknown others, the current investigation proposed that anticipated guilt is a motivating force behind individuals'…

  20. College Readiness vs College Admissions: Will We Resolve the Chasm between K-12 and Higher Education?

    ERIC Educational Resources Information Center

    Camara, Wayne

    2008-01-01

    Presented at the conference for USC Center for Enrollment Research, Policy and Practice (CERRP). This provides an overview of the various studies currently underway to establish the validity of noncognitive measures of success as a supplement to current cognitive measures which are used. Comparisons between what is defined as college readiness and…

  1. The dynamics of certain indicators of nuclein metabolism during hypokinesia in rats of different ages under the influence of sinusoidal modulated currents and measured physical load

    NASA Technical Reports Server (NTRS)

    Sokolova, Z. A.

    1980-01-01

    The influence of sinusoidal modulated currents was studied and physical loads on the nucleic acid content and the nucleotide composition of the total RNA in muscles of rats of various ages under conditions of hypodynamia were measured. Methodology utilized is described and conclusions are presented.

  2. Current State of Environmental Education in Mexico: A Study on Practices, Audiences, Settings, and Topics

    ERIC Educational Resources Information Center

    Marcos-Iga, Jose; Shaw, William

    2011-01-01

    Environmental education in Mexico takes many forms and plays a wide variety of roles. Through an online survey, we addressed the need to present a wider picture on the current state of environmental education practices in Mexico: Who is engaging in environmental education practices, how important is it for their organization, who are they…

  3. Dimensional Structure of the Autism Phenotype: Relations between Early Development and Current Presentation

    ERIC Educational Resources Information Center

    Kamp-Becker, Inge; Ghahreman, Mardjan; Smidt, Judith; Remschmidt, Helmut

    2009-01-01

    The dimensional structure of higher functioning autism phenotype was investigated by factor analysis. The goal of this study was to identify the degree to which early symptoms of autism (measured using the ADI-R) could be predictive of the current symptoms of autism as identified using the ADOS, the adaptive behavior scales, IQ scores and theory…

  4. Eddy Current Testing, RQA/M1-5330.17.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Huntsville, AL. George C. Marshall Space Flight Center.

    As one in the series of classroom training handbooks, prepared by the U.S. space program, instructional material is presented in this volume concerning familiarization and orientation on eddy current testing. The subject is presented under the following headings: Introduction, Eddy Current Principles, Eddy Current Equipment, Eddy Current Methods,…

  5. Development and investigation of silicon converter beta radiation 63Ni isotope

    NASA Astrophysics Data System (ADS)

    Krasnov, A. A.; Legotin, S. A.; Murashev, V. N.; Didenko, S. I.; Rabinovich, O. I.; Yurchuk, S. Yu; Omelchenko, Yu K.; Yakimov, E. B.; Starkov, V. V.

    2016-02-01

    In this paper the results of the creation and researching characteristics of, experimental betavoltaic converters (BVC), based on silicon are discussed. It was presented the features of structural and technological performance of planar 2 D- structure of BVC. To study the parameters of the converter stream the beta particles of the radioisotope was simulated by 63Ni electron flux from scanning electron microscope. It was investigated the dependence of the collecting electrons efficiency from the beam energy current-voltage characteristic was measured when irradiated by an electron beam, from which the value of the short-circuit current density equal to 126 nA / cm2 and the value of the open circuit voltage of 150 mV were obtained. The maximum power density at 70 mV is 9.5 nW / cm2, and the conversion efficiency is 2.1%. It was presented the results of experimental studies of the current-voltage characteristics of samples by irradiating a film 63Ni. The values of load voltage 111 mV and short circuit current density of 27 nA / cm2 were obtained. Maximum power density was 1.52 nW / cm2.

  6. Generation of Electricity Using Spartina Patens with Stainless Steel Current Collectors in a Plant-Microbial Fuel Cell

    NASA Astrophysics Data System (ADS)

    Narula, Deep

    At present, the global energy infrastructure is highly dependent on (i) non-renewable fossil fuels with significant emissions of greenhouse gasses (ii) green fuels such as bioethanol and biodiesel with impact on current agricultural practices competing with food production for arable lands, fertilizers, also requiring additional energy input. Plant-based microbial fuel cell (PMFC) technology can be found as a promising alternative to produce electricity without any side effects with an advantage of using sunlight as an energy source. In the present study, we developed PMFCs using Spartina patens, a marshland grass, abundantly available in the coastal regions of the USA. Figure 1 is a schematic for a PMFC with the anode and cathode compartments where others have used carbon-based electrodes for current collection. In contrast, we attempted to utilize stainless steel wires with more surface area to enhance the current collection in the anode compartment as well as to increase the rate of reduction in the cathode chamber and thereby increase the amount of electricity produced. The study will give results on the periodic use of Spartina patens in PMFC along with the porous stainless steel electrodes which have never been employed in PMFCs before.

  7. Nitric oxide augments voltage-activated calcium currents of crustacea (Idotea baltica) skeletal muscle.

    PubMed

    Erxleben, C; Hermann, A

    2001-03-16

    Invertebrate skeletal muscle contraction is regulated by calcium influx through voltage-dependent calcium channels in the sarcolemmal membrane. In present study we investigated the effects of nitric oxide (NO) donors on calcium currents of single skeletal muscle fibres from the marine isopod, Idotea baltica, using two-electrode voltage clamp recording techniques. The NO donors, S-nitrosocysteine, S-nitroso-N-acetyl-penicillamine or hydroxylamine reversibly increased calcium inward currents in a time dependent manner. The increase of the current was prevented by methylene blue. Our experiments suggest that NO increases calcium inward currents. NO, by acting on calcium ion channels in the sarcolemmal membrane, therefore, may directly be involved in the modulation of muscle contraction.

  8. Characterizing a December 2005 density current event in the Chicago River, Chicago, Illinois

    USGS Publications Warehouse

    Garcia, C.M.; Jackson, P.R.; Oberg, K.A.; Johnson, K.K.; Garcia, M.H.

    2007-01-01

    During the winter months, the Chicago River in Chicago, Illinois is subject to bi-directional flows, and density currents are thought to be responsible for these flow variations. This paper presents detailed field measurements using three acoustic Doppler current profiler instruments and simultaneous water-quality measurements made during December 2005. Observations indicate that the formation of density currents within the Chicago River and density differences are mostly due to salinity differences between the North Branch and the main stem of the Chicago River, whereas temperature difference does not appreciably affect the creation of density currents. Sources of higher water temperature, conductivity, and salinity values should be addressed in future studies. ?? 2007 ASCE.

  9. A squid-based beam current monitor for FAIR/CRYRING

    NASA Astrophysics Data System (ADS)

    Geithner, Rene; Kurian, Febin; Reeg, Hansjörg; Schwickert, Marcus; Neubert, Ralf; Seidel, Paul; Stöhlker, Thomas

    2015-11-01

    A SQUID-based beam current monitor was developed for the upcoming FAIR-Project, providing a non-destructive online monitoring of the beam currents in the nA-range. The cryogenic current comparator (CCC) was optimized for lowest possible noise-limited current resolution together with a high system bandwidth. This CCC is foreseen to be installed in the CRYRING facility (CRYRING@ESR: A study group report www.gsi.de/fileadmin/SPARC/documents/Cryring/ReportCryring_40ESR.PDF), working as a test bench for FAIR. In this contribution we present results of the completed CCC for FAIR/CRYRING and also arrangements that have been done for the installation of the CCC at CRYRING, regarding the cryostat design.

  10. Gilbert W. Beebe Symposium on 30 Years after the Chernobyl Accident: Current and Future Studies on Radiation Health Effects.

    PubMed

    Samet, Jonathan M; de González, Amy Berrington; Dauer, Lawrence T; Hatch, Maureen; Kosti, Ourania; Mettler, Fred A; Satyamitra, Merriline M

    2018-01-01

    This commentary summarizes the presentations and discussions from the 2016 Gilbert W. Beebe symposium "30 years after the Chernobyl accident: Current and future studies on radiation health effects." The symposium was hosted by the National Academies of Sciences, Engineering, and Medicine (the National Academies). The symposium focused on the health consequences of the Chernobyl accident, looking retrospectively at what has been learned and prospectively at potential future discoveries using emerging 21st Century research methodologies.

  11. Recommendations and Guidelines, The Incorporation of Results of Current Crustal Evolution Studies into K-12 Curricula. A Report of the National Association of Geology Teachers Conference on K-12 Crustal Evolution Education (Western Hills State Lodge, Oklahoma, September 16-18, 1974).

    ERIC Educational Resources Information Center

    Stoever, Edward C., Jr.

    The National Association of Geology Teachers (NAGT) conducted an assessment of the implications of current studies encompassing the theories of continental drift, polar wandering, sea-floor spreading, and plate tectonics to K-12 education, and presented in this document recommendations for the incorporation of these concepts into school curricula.…

  12. Active Structural Control for Aircraft Efficiency with the X-56A Aircraft

    NASA Technical Reports Server (NTRS)

    Ouellette, Jeffrey

    2015-01-01

    The X-56A Multi-Utility Technology Testbed is an experimental aircraft designed to study active control of flexible structures. The vehicle is easily reconfigured to allow for testing of different configurations. The vehicle is being used to study new sensor, actuator, modeling and controls technologies. These new technologies will allow for lighter vehicles and new configurations that exceed the efficiency currently achievable. A description of the vehicle and the current research efforts that it enables are presented.

  13. Estimating the prevalence of infertility in Canada

    PubMed Central

    Bushnik, Tracey; Cook, Jocelynn L.; Yuzpe, A. Albert; Tough, Suzanne; Collins, John

    2012-01-01

    BACKGROUND Over the past 10 years, there has been a significant increase in the use of assisted reproductive technologies in Canada, however, little is known about the overall prevalence of infertility in the population. The purpose of the present study was to estimate the prevalence of current infertility in Canada according to three definitions of the risk of conception. METHODS Data from the infertility component of the 2009–2010 Canadian Community Health Survey were analyzed for married and common-law couples with a female partner aged 18–44. The three definitions of the risk of conception were derived sequentially starting with birth control use in the previous 12 months, adding reported sexual intercourse in the previous 12 months, then pregnancy intent. Prevalence and odds ratios of current infertility were estimated by selected characteristics. RESULTS Estimates of the prevalence of current infertility ranged from 11.5% (95% CI 10.2, 12.9) to 15.7% (95% CI 14.2, 17.4). Each estimate represented an increase in current infertility prevalence in Canada when compared with previous national estimates. Couples with lower parity (0 or 1 child) had significantly higher odds of experiencing current infertility when the female partner was aged 35–44 years versus 18–34 years. Lower odds of experiencing current infertility were observed for multiparous couples regardless of age group of the female partner, when compared with nulliparous couples. CONCLUSIONS The present study suggests that the prevalence of current infertility has increased since the last time it was measured in Canada, and is associated with the age of the female partner and parity. PMID:22258658

  14. Speech Alarms Pilot Study

    NASA Technical Reports Server (NTRS)

    Sandor, A.; Moses, H. R.

    2016-01-01

    Currently on the International Space Station (ISS) and other space vehicles Caution & Warning (C&W) alerts are represented with various auditory tones that correspond to the type of event. This system relies on the crew's ability to remember what each tone represents in a high stress, high workload environment when responding to the alert. Furthermore, crew receive a year or more in advance of the mission that makes remembering the semantic meaning of the alerts more difficult. The current system works for missions conducted close to Earth where ground operators can assist as needed. On long duration missions, however, they will need to work off-nominal events autonomously. There is evidence that speech alarms may be easier and faster to recognize, especially during an off-nominal event. The Information Presentation Directed Research Project (FY07-FY09) funded by the Human Research Program included several studies investigating C&W alerts. The studies evaluated tone alerts currently in use with NASA flight deck displays along with candidate speech alerts. A follow-on study used four types of speech alerts to investigate how quickly various types of auditory alerts with and without a speech component - either at the beginning or at the end of the tone - can be identified. Even though crew were familiar with the tone alert from training or direct mission experience, alerts starting with a speech component were identified faster than alerts starting with a tone. The current study replicated the results from the previous study in a more rigorous experimental design to determine if the candidate speech alarms are ready for transition to operations or if more research is needed. Four types of alarms (caution, warning, fire, and depressurization) were presented to participants in both tone and speech formats in laboratory settings and later in the Human Exploration Research Analog (HERA). In the laboratory study, the alerts were presented by software and participants were asked to identify the alert as quickly and as accurately as possible. Reaction time and accuracy were measured. Participants identified speech alerts significantly faster than tone alerts. The HERA study investigated the performance of participants in a flight-like environment. Participants were instructed to complete items on a task list and respond to C&W alerts as they occurred. Reaction time and accuracy were measured to determine if the benefits of speech alarms are still present in an applied setting.

  15. The ionic bases of the action potential in isolated mouse cardiac Purkinje cell.

    PubMed

    Vaidyanathan, Ravi; O'Connell, Ryan P; Deo, Makarand; Milstein, Michelle L; Furspan, Philip; Herron, Todd J; Pandit, Sandeep V; Musa, Hassan; Berenfeld, Omer; Jalife, José; Anumonwo, Justus M B

    2013-01-01

    Collecting electrophysiological and molecular data from the murine conduction system presents technical challenges. Thus, only little advantage has been taken of numerous genetically engineered murine models to study excitation through the cardiac conduction system of the mouse. To develop an approach for isolating murine cardiac Purkinje cells (PCs), to characterize major ionic currents and to use the data to simulate action potentials (APs) recorded from PCs. Light microscopy was used to isolate and identify PCs from apical and septal cells. Current and voltage clamp techniques were used to record APs and whole cell currents. We then simulated a PC AP on the basis of our experimental data. APs recorded from PCs were significantly longer than those recorded from ventricular cells. The prominent plateau phase of the PC AP was very negative (≈-40 mV). Spontaneous activity was observed only in PCs. The inward rectifier current demonstrated no significant differences compared to ventricular myocytes (VMs). However, sodium current density was larger, and the voltage-gated potassium current density was significantly less in PCs compared with myocytes. T-type Ca(2+) currents (I(Ca,T)) were present in PCs but not VMs. Computer simulations suggest that I(Ca,T) and cytosolic calcium diffusion significantly modulate AP profile recorded in PCs, as compared to VMs. Our study provides the first comprehensive ionic profile of murine PCs. The data show unique features of PC ionic mechanisms that govern its excitation process. Experimental data and numerical modeling results suggest that a smaller voltage-gated potassium current and the presence of I(Ca,T) are important determinants of the longer and relatively negative plateau phase of the APs. Copyright © 2013 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  16. Monitoring the quality of welding based on welding current and ste analysis

    NASA Astrophysics Data System (ADS)

    Mazlan, Afidatusshimah; Daniyal, Hamdan; Izzani Mohamed, Amir; Ishak, Mahadzir; Hadi, Amran Abdul

    2017-10-01

    Qualities of welding play an important part in industry especially in manufacturing field. Post-welding non-destructive test is one of the importance process to ensure the quality of welding but it is time consuming and costly. To reduce the chance of defects, online monitoring had been utilized by continuously sense some of welding parameters and predict welding quality. One of the parameters is welding current, which is rich of information but lack of study focus on extract them at signal analysis level. This paper presents the analysis of welding current using Short Time Energy (STE) signal processing to quantify the pattern of the current. GMAW set with carbon steel specimens are used in this experimental study with high-bandwidth and high sampling rate oscilloscope capturing the welding current. The results indicate welding current as signatures have high correlation with the welding process. Continue with STE analysis, the value below 5000 is declare as good welding, meanwhile the STE value more than 6000 is contained defect.

  17. Presentation of Projects, 1975/76.

    ERIC Educational Resources Information Center

    Swedish Broadcasting Corp., Stockholm.

    Research projects currently underway at the Audience and Programme Research Department of Sweden's Sveriges Radio are divided into four areas: studies of children, information studies, audience studies, and adult education studies. The focus of the ten projects being pursued by the children's group is on the effect of the broadcast media on…

  18. Trends and predicted trends in presentations of older people to Australian emergency departments: effects of demand growth, population aging and climate change.

    PubMed

    Burkett, Ellen; Martin-Khan, Melinda G; Scott, Justin; Samanta, Mayukh; Gray, Leonard C

    2017-07-01

    Objectives The aim of the present study was to describe trends in and age and gender distributions of presentations of older people to Australian emergency departments (EDs) from July 2006 to June 2011, and to develop ED utilisation projections to 2050. Methods A retrospective analysis of data collected in the National Non-admitted Patient Emergency Department Care Database was undertaken to assess trends in ED presentations. Three standard Australian Bureau of Statistics population growth models, with and without adjustment for current trends in ED presentation growth and effects of climate change, were examined with projections of ED presentations across three age groups (0-64, 65-84 and ≥85 years) to 2050. Results From 2006-07 to 2010-11, ED presentations increased by 12.63%, whereas the Australian population over this time increased by only 7.26%. Rates of presentation per head of population were greatest among those aged ≥85 years. Projections of ED presentations to 2050 revealed that overall ED presentations are forecast to increase markedly, with the rate of increase being most marked for older people. Conclusion Growth in Australian ED presentations from 2006-07 to 2010-11 was greater than that expected from population growth alone. The predicted changes in demand for ED care will only be able to be optimally managed if Australian health policy, ED funding instruments and ED models of care are adjusted to take into account the specific care and resource needs of older people. What is known about the topic? Rapid population aging is anticipated over coming decades. International studies and specific local-level Australian studies have demonstrated significant growth in ED presentations. There have been no prior national-level Australian studies of ED presentation trends by age group. What does this paper add? The present study examined national ED presentation trends from July 2006 to June 2011, with specific emphasis on trends in presentation by age group. ED presentation growth was found to exceed population growth in all age groups. The rate of ED presentations per head of population was highest among those aged ≥85 years. ED utilisation projections to 2050, using standard Australian Bureau of Statistics population modelling, with and without adjustment for current ED growth, were developed. The projections demonstrated linear growth in ED presentation for those aged 0-84 years, with growth in ED presentations of the ≥85 year age group demonstrating marked acceleration after 2030. What are the implications for practitioners? Growth in ED presentations exceeding population growth suggests that current models of acute health care delivery require review to ensure that optimal care is delivered in the most fiscally efficient manner. Trends in presentation of older people emphasise the imperative for ED workforce planning and education in care of this complex patient cohort, and the requirement to review funding models to incentivise investment in ED avoidance and substitutive care models targeting older people.

  19. Current status and perspectives of the development of dental research in biological anthropology of Argentina: introduction and conclusions of the symposium.

    PubMed

    Luna, Leandro H; Bernal, Valeria

    2011-10-01

    This paper describes and discusses the research in the field of dental anthropology in Argentina. It has been presented at the symposium entitled "The development of dental research in Argentine Biological Anthropology: current status and perspectives", coordinated by the authors at the IX National Meeting of Biological Anthropology of Argentina, Puerto Madryn, 20th-23rd October 2009. The aim of the symposium was to present new results and future prospects of this discipline in the country and to create a forum for discussion of current research within this field. Six contributions that focused on the study of teeth from different perspectives and analysed bioarchaeological samples from different areas of Argentina (Central Highlands, Pampa and Patagonia) were presented. After the presentations, a discussion about the state of the art of dental research in the country was generated, in which the need for the generation of methodological consensus on the criteria for the evaluation of the variables considered was stated, so that research conducted in different areas can be compared. In short, the contributions of this symposium provide insights into the diversity of dental anthropology in contemporary Argentina and the potential of these types of studies to gain important information about biological and cultural aspects of the native populations in the country. Copyright © 2011 Elsevier GmbH. All rights reserved.

  20. Error processing in current and former cocaine users

    PubMed Central

    Castelluccio, Brian C.; Meda, Shashwath A.; Muska, Christine E.; Stevens, Michael C.; Pearlson, Godfrey D.

    2013-01-01

    Deficits in response inhibition and error processing can result in maladaptive behavior, including failure to use past mistakes to inform present decisions. A specific deficit in inhibiting a prepotent response represents one aspect of impulsivity and is a prominent feature of addictive behaviors in general, including cocaine abuse/dependence. Brain regions implicated in cognitive control exhibit reduced activation in cocaine abusers. The purposes of the present investigation were (1) to identify neural differences associated with error processing in current and former cocaine-dependent individuals compared to healthy controls and (2) to determine whether former, long-term abstinent cocaine users showed similar differences compared with current users. The present study used an fMRI Go/No-Go task to investigate differences in BOLD response to correct rejections and false alarms between current cocaine users (n=30), former cocaine users (n=29), and healthy controls (n=35). Impulsivity trait measures were also assessed and compared with BOLD activity. Nineteen regions of interest previously implicated in errors of disinhibition were queried. There were no group differences in the correct rejections condition, but both current and former users exhibited increased BOLD response relative to controls for false alarms. In current users, the pregenual cingulate gyrus and left angular/supramarginal gyri overactivated. In former users, the right middle frontal/precentral gyri, right inferior parietal lobule, and left angular/supramarginal gyri overactivated. Overall, our results support a hypothesis that neural activity in former users differs more from healthy controls than that of current users due to cognitive compensation that facilitates abstinence. PMID:23949893

  1. Poleward currents from coastal altimetry: The west coast of Southern Baja California, Mexico

    NASA Astrophysics Data System (ADS)

    Valle-Rodríguez, J.; Trasviña-Castro, A.

    2017-05-01

    The west coast of Southern Baja California is subject to intense seasonal variability, presenting lowest temperatures from February to April partly due to the upwelling season but also to cold water advection associated to the California Current. The summer advance of a poleward current is responsible for the coastal temperature maxima. In this work we use a time series of currents from a moored Acoustic Doppler Profiler (ADP) to validate coastal altimetry data, in order to study seasonal and interannual coastal current variability. Almost eleven years of coastal altimetry data (2002-2012) from X-TRACK, 20-40 km from the coast, reveal a persistent seasonal poleward flow from July to October and equatorward flow, modulated by mesoscale processes the rest of the year. Near the coast of the peninsula sea level raises towards the coast while the poleward current carries a warm water mass against the climatological wind. It is present from July to October in a coastal band 100 km wide from the surface to 80 m depth with speeds 0.2-0.3 m s-1. The interannual variability observed in this period is unusually weak, compared to the previous decade.

  2. A novel mechanism for electrical currents inducing ventricular fibrillation: The three-fold way to fibrillation.

    PubMed

    Kroll, Mark W; Panescu, Dorin; Hinz, Andrew F; Lakkireddy, Dhanunjaya

    2010-01-01

    It has been long recognized that there are 2 methods for inducing VF (ventricular fibrillation) with electrical currents‥ These are: (1) delivering a high-charge shock into the cardiac T-wave, and (2) delivering lower level currents for 1-5 seconds. Present electrical safety standards are based on this understanding. We present new data showing a 3(rd) mechanism of inducing VF which involves the steps of delivering sufficient current to cause high-rate cardiac capture, causing cardiac output collapse, leading to ischemia, for sufficiently long duration, which then lowers the VFT (VF threshold) to the level of the current, which finally results in VF. This requires about 40% of the normal VF-induction current but requires a duration of minutes instead of seconds for the VF to be induced. Anesthetized and ventilated swine (n=6) had current delivered from a probe tip 10 mm from the epicardium sufficient to cause hypotensive capture but not directly induce VF within 5 s. After a median time of 90 s, VF was induced. This 3(rd) mechanism of VF induction should be studied further and considered for electrical safety standards and is relevant to long-duration TASER Electronic Control Device applications.

  3. New Technique of AC drive in Tokamak using Permanent Magnets

    NASA Astrophysics Data System (ADS)

    Matteucci, Jackson; Zolfaghari, Ali

    2013-10-01

    This study investigates a new technique of capturing the rotational energy of alternating permanent magnets in order to inductively drive an alternating current in tokamak devices. The use of rotational motion bypasses many of the pitfalls seen in typical inductive and non-inductive current drives. Three specific designs are presented and assessed in the following criteria: the profile of the current generated, the RMS loop voltage generated as compared to the RMS power required to maintain it, the system's feasibility from an engineering perspective. All of the analysis has been done under ideal E&M conditions using the Maxwell 3D program. Preliminary results indicate that it is possible to produce an over 99% purely toroidal current with a RMS d Φ/dt of over 150 Tm2/s, driven by 20 MW or less of rotational power. The proposed mechanism demonstrates several key advantages including an efficient mechanical drive system, the generation of pure toroidal currents, and the potential for a quasi-steady state fusion reactor. The following quantities are presented for various driving frequencies and magnet strengths: plasma current generated, loop voltage, torque and power required. This project has been supported by DOE Funding under the SULI program.

  4. Current Status of Chemical Public Health Risks and Testing ...

    EPA Pesticide Factsheets

    The cardiovascular system, at all its various developmental and life stages, represents a critical target organ system that can be adversely affected by a variety of chemicals and routes of exposure. A World Health Organization report estimated the impact of environmental chemical exposures on health to be 16% (range: 7—23%) of the total global burden of cardiovascular disease, corresponding to ~2.5 million deaths per year. Currently, the overall impact of environmental chemical exposures on all causes of cardiovascular disease and the number one cause of morbidity and mortality in the United States is unknown. Evidence from epidemiology, clinical, and toxicological studies will be presented documenting adverse cardiovascular effects associated with environmental exposure to chemicals. The presentation will cover US EPA’s ability to regulate and test chemicals as well as current challenges faced by the Agency to assess chemical cardiovascular risk and public health safety. (This abstract does not necessarily reflect US EPA Policy) Will be presented at the Workshop titled

  5. Electrochemical Treatment of Textile Dye Wastewater by Mild Steel Anode.

    PubMed

    Bhavya, J G; Rekha, H B; Murthy, Usha N

    2014-04-01

    This paper presents the results of the treatment of textile dye wastewater generated from a textile processing industry by electrochemical method. Experiments were conducted at current densities of 12, 24 and 48 A/m2 using mild steel as anode and cathode. During the various stages of electrolysis, parameters such as COD, color and BOD5 were determined in order to know the feasibility of electrochemical treatment. It was observed that increasing the electrolysis time and increased current density bring down the concentration of pollutants. Also COD removal rate and energy consumption during the electrolysis were calculated and presented in this paper. The present study proves the effectiveness of electrochemical treatment using MS as anode for TDW oxidation.

  6. High Current Plasma Electrolytic Oxidation Coating Processes for Wear and Corrosion Prevention of Al 2024

    NASA Astrophysics Data System (ADS)

    Wang, Rui

    Plasma electrolytic oxidation (PEO) treatments have been used in the aerospace and automotive industries because the coating formed on light metals or alloys has great hardness, high wear, corrosion, and oxidation resistance, and a low friction coefficient that improves lifetime length and provide a higher surface quality. However, the PEO treatments that are presently used for industrial applications require a long period of time to confirm the quality of the coating. For this reason, the present study seeks to increase the current density of PEO treatments to improve their efficiency and explore the performance of the obtained coatings. It was found that for high current density (0.18A/cm2) PEO treatments, smaller ratio, such as 50% and 70%, is beneficial to obtaining a better performance coating. When compared with the coating of a "normal" (current density: 0.09A/cm2) PEO treatment, it had better wear resistance; however, for corrosion resistance, it had a lower performance than the coatings obtained by the "normal" current density PEO treatment which was attributed to the negative influence of porosity increase.

  7. Economic effects of propulsion system technology on existing and future transport aircraft

    NASA Technical Reports Server (NTRS)

    Sallee, G. P.

    1974-01-01

    The results of an airline study of the economic effects of propulsion system technology on current and future transport aircraft are presented. This report represents the results of a detailed study of propulsion system operating economics. The study has four major parts: (1) a detailed analysis of current propulsion system maintenance with respect to the material and labor costs encountered versus years in service and the design characteristics of the major elements of the propulsion system of the B707, b727, and B747. (2) an analysis of the economic impact of a future representative 1979 propulsion system is presented with emphasis on depreciation of investment, fuel costs and maintenance costs developed on the basis of the analysis of the historical trends observed. (3) recommendations concerning improved methods of forecasting the maintenance cost of future propulsion systems are presented. A detailed method based on the summation of the projected labor and material repair costs for each major engine module and its installation along with a shorter form suitable for quick, less detailed analysis are presented, and (4) recommendations concerning areas where additional technology is needed to improve the economics of future commercial propulsion systems are presented along with the suggested economic benefits available from such advanced technology efforts.

  8. Positive direct current corona discharges in single wire-duct electrostatic precipitators

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

    Yehia, Ashraf, E-mail: yehia30161@yahoo.com; Department of Physics, Faculty of Science, Assiut University, Assiut 71516, Arab Republic of Egypt; Abdel-Fattah, E.

    This paper is aimed to study the characteristics of the positive dc corona discharges in single wire-duct electrostatic precipitators. Therefore, the corona discharges were formed inside dry air fed single wire-duct reactor under positive dc voltage at the normal atmospheric conditions. The corona current-voltage characteristics curves have been measured in parallel with the ozone concentration generated inside the reactor under different discharge conditions. The corona current-voltage characteristics curves have agreed with a semi empirical equation derived from the previous studies. The experimental results of the ozone concentration generated inside the reactor were formulated in the form of an empirical equationmore » included the different parameters that were studied experimentally. The obtained equations are valid to expect both the current-voltage characteristics curves and the corresponding ozone concentration that generates with the positive dc corona discharges inside single wire-duct electrostatic precipitators under any operating conditions in the same range of the present study.« less

  9. Effects of Tannic Acid, Green Tea and Red Wine on hERG Channels Expressed in HEK293 Cells.

    PubMed

    Chu, Xi; Guo, Yusong; Xu, Bingyuan; Li, Wenya; Lin, Yue; Sun, Xiaorun; Ding, Chunhua; Zhang, Xuan

    2015-01-01

    Tannic acid presents in varying concentrations in plant foods, and in relatively high concentrations in green teas and red wines. Human ether-à-go-go-related gene (hERG) channels expressed in multiple tissues (e.g. heart, neurons, smooth muscle and cancer cells), and play important roles in modulating cardiac action potential repolarization and tumor cell biology. The present study investigated the effects of tannic acid, green teas and red wines on hERG currents. The effects of tannic acid, teas and red wines on hERG currents stably transfected in HEK293 cells were studied with a perforated patch clamp technique. In this study, we demonstrated that tannic acid inhibited hERG currents with an IC50 of 3.4 μM and ~100% inhibition at higher concentrations, and significantly shifted the voltage dependent activation to more positive potentials (Δ23.2 mV). Remarkably, a 100-fold dilution of multiple types of tea (green tea, oolong tea and black tea) or red wine inhibited hERG currents by ~90%, and significantly shifted the voltage dependent activation to more positive potentials (Δ30.8 mV and Δ26.0 mV, respectively). Green tea Lung Ching and red wine inhibited hERG currents, with IC50 of 0.04% and 0.19%, respectively. The effects of tannic acid, teas and red wine on hERG currents were irreversible. These results suggest tannic acid is a novel hERG channel blocker and consequently provide a new mechanistic evidence for understanding the effects of tannic acid. They also revealed the potential pharmacological basis of tea- and red wine-induced biology activities.

  10. Effects of Tannic Acid, Green Tea and Red Wine on hERG Channels Expressed in HEK293 Cells

    PubMed Central

    Xu, Bingyuan; Li, Wenya; Lin, Yue; Sun, Xiaorun; Ding, Chunhua; Zhang, Xuan

    2015-01-01

    Tannic acid presents in varying concentrations in plant foods, and in relatively high concentrations in green teas and red wines. Human ether-à-go-go-related gene (hERG) channels expressed in multiple tissues (e.g. heart, neurons, smooth muscle and cancer cells), and play important roles in modulating cardiac action potential repolarization and tumor cell biology. The present study investigated the effects of tannic acid, green teas and red wines on hERG currents. The effects of tannic acid, teas and red wines on hERG currents stably transfected in HEK293 cells were studied with a perforated patch clamp technique. In this study, we demonstrated that tannic acid inhibited hERG currents with an IC50 of 3.4 μM and ~100% inhibition at higher concentrations, and significantly shifted the voltage dependent activation to more positive potentials (Δ23.2 mV). Remarkably, a 100-fold dilution of multiple types of tea (green tea, oolong tea and black tea) or red wine inhibited hERG currents by ~90%, and significantly shifted the voltage dependent activation to more positive potentials (Δ30.8 mV and Δ26.0 mV, respectively). Green tea Lung Ching and red wine inhibited hERG currents, with IC50 of 0.04% and 0.19%, respectively. The effects of tannic acid, teas and red wine on hERG currents were irreversible. These results suggest tannic acid is a novel hERG channel blocker and consequently provide a new mechanistic evidence for understanding the effects of tannic acid. They also revealed the potential pharmacological basis of tea- and red wine-induced biology activities. PMID:26625122

  11. Preliminary investigation on the use of low current pulsed power Z-pinch plasma devices for the study of early stage plasma instabilities

    NASA Astrophysics Data System (ADS)

    Kaselouris, E.; Dimitriou, V.; Fitilis, I.; Skoulakis, A.; Koundourakis, G.; Clark, E. L.; Chatzakis, J.; Bakarezos, Μ; Nikolos, I. K.; Papadogiannis, N. A.; Tatarakis, M.

    2018-01-01

    This article addresses key features for the implementation of low current pulsed power plasma devices for the study of matter dynamics from the solid to the plasma phase. The renewed interest in such low current plasma devices lies in the need to investigate methods for the mitigation of prompt seeding mechanisms for the generation of plasma instabilities. The low current when driven into thick wires (skin effect mode) allows for the simultaneous existence of all phases of matter from solid to plasma. Such studies are important for the concept of inertial confinement fusion where the mitigation of the instability seeding mechanisms arising from the very early moments within the target’s heating is of crucial importance. Similarly, in the magnetized liner inertial fusion concept it is an open question as to how much surface non-uniformity correlates with the magneto-Rayleigh-Taylor instability, which develops during the implosion. This study presents experimental and simulation results, which demonstrate that the use of low current pulsed power devices in conjunction with appropriate diagnostics can be important for studying seeding mechanisms for the imminent generation of plasma instabilities in future research.

  12. Approaches to Studying and Students' Use of a Computer Supported Learning Environment

    ERIC Educational Resources Information Center

    Foster, Jonathan; Lin, Angela

    2007-01-01

    Although studies of students' study approaches in face to face learning environments are commonplace, studies investigating the role of students' study approaches in online learning environments is currently a less explored area. This paper presents the findings of a survey aimed at investigating the relationship between students' approaches to…

  13. Illustrative Projections of World Populations to the 21st Century. Current Population Reports, Special Studies Series P-23, No. 79.

    ERIC Educational Resources Information Center

    Moore, Maurice J., Ed.; O'Connell, Martin, Ed.

    The document presents high, medium, and low projections of the world's population for the year 2000. The objective of the study is to determine demands on natural resources and the environment which will be brought about by changes in the world's population. The document is presented in three major sections. Section I provides an overview of the…

  14. Implementation of Virtualization Oriented Architecture: A Healthcare Industry Case Study

    NASA Astrophysics Data System (ADS)

    Rao, G. Subrahmanya Vrk; Parthasarathi, Jinka; Karthik, Sundararaman; Rao, Gvn Appa; Ganesan, Suresh

    This paper presents a Virtualization Oriented Architecture (VOA) and an implementation of VOA for Hridaya - a Telemedicine initiative. Hadoop Compute cloud was established at our labs and jobs which require a massive computing capability such as ECG signal analysis were submitted and the study is presented in this current paper. VOA takes advantage of inexpensive community PCs and provides added advantages such as Fault Tolerance, Scalability, Performance, High Availability.

  15. Structural concepts for very large (400-meter-diameter) solar concentrators

    NASA Technical Reports Server (NTRS)

    Mikulas, Martin M., Jr.; Hedgepeth, John M.

    1989-01-01

    A general discussion of various types of large space structures is presented. A brief overview of the history of space structures is presented to provide insight into the current state-of-the art. Finally, the results of a structural study to assess the viability of very large solar concentrators are presented. These results include weight, stiffness, part count, and in-space construction time.

  16. The Present in Flemish Secondary History Education through the Lens of Written History Exams

    ERIC Educational Resources Information Center

    Van Nieuwenhuyse, Karel; Wils, Kaat; Clarebout, Geraldine; Verschaffel, Lieven

    2015-01-01

    The present plays an important part in history education, in particular in efforts to make the study of the past relevant for today. This contribution examines how the relationship between past and present is dealt with in current Flemish secondary history education by analyzing 190 written history exams for the 11th and 12th grade. Ten percent of…

  17. Examining temporal alterations in Social Anxiety Disorder and Posttraumatic Stress Disorder: The relation between autobiographical memory, future goals, and current self-views.

    PubMed

    Krans, Julie; Peeters, Manon; Näring, Gérard; Brown, Adam D; de Bree, June; van Minnen, Agnes

    2017-12-01

    The self is a multi-faceted and temporally dynamic construct reflecting representations and beliefs about identity in the past, present, and future. Clinical studies have shown that individuals with Posttraumatic Stress Disorder (PTSD) and Social Anxiety Disorder (SAD) exhibit alterations in self-related processing but these studies have focused primarily on memory. Few studies in PTSD and SAD have examined self-related processing for the present and future, and no studies have directly compared these processes across these two disorders. Individuals diagnosed with PTSD (n=21), SAD (n=21), and healthy controls (n=21) completed cognitive tasks related to the past, present, and future. Disorder congruent temporal alterations were found across both disorders. Further, regression analyses revealed that trauma-related memories were significantly predicted by future goals related to the trauma, whereas social anxiety-related recall was predicted by current socially anxious self-views. Thus, although self-related processing may be common in PTSD and SAD, those aspects of the self most strongly associated with disorder-congruent recall differ by disorder. Self-alterations may be modifiable and developing a better understanding of past, present, and future self-processing might aid in the development of interventions that target these process. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Community Readiness as a Multidimensional Construct

    ERIC Educational Resources Information Center

    Chilenski, Sarah M.; Greenberg, Mark T.; Feinberg, Mark E.

    2007-01-01

    Both the organizational studies literature and the community psychology literature discuss the importance of readiness when implementing change. Although each area emphasizes different characteristics, several common themes are present within the literature. The current study integrates and applies organizational and community psychology…

  19. [Localization of attention related cortical structures by evoked potentials].

    PubMed

    Szelenberger, W

    2000-01-01

    Attention is an ambiguous concept, difficult to direct implementation in neurophysiological studies. The paper presents application of the Continuous Attention Test (CAT) items as stimuli in event related potential (ERP) studies on attention. Stimuli with high demand of attention result in enlarged N1 component in occipital derivations. Spatial analysis revealed increased positivity in frontal derivations. Three-dimensional image of cortical current density by means of Low Resolution Electromagnetic Tomography (LORETA) revealed sources of N1 component in occipital, parietal and postero-temporal derivations with the maximal current value at 17 Brodmann area. After target stimuli increase of current density in frontal derivations was observed, with the maximal value in the left 9 Brodmann area.

  20. Dietary ω-3 polyunsaturated fatty acids improves learning performance of diabetic rats by regulating the neuron excitability.

    PubMed

    Yang, R-H; Wang, F; Hou, X-H; Cao, Z-P; Wang, B; Xu, X-N; Hu, S-J

    2012-06-14

    Previous research has demonstrated that diabetes induced learning and memory deficits. However, the mechanism of memory impairment induced by diabetes is poorly understood. Dietary fatty acids, especially polyunsaturated fatty acids (PUFA), have been shown to enhance learning and memory and prevent memory deficits in various experimental conditions. Sprague-Dawley rats were used in the present study to investigate the effect of fish oil supplementation on spatial learning and memory of streptozotocin (STZ)-induced diabetic rats with the Morris Water Maze. The excitability of CA1 pyramidal neurons and the related ionic currents was also examined. Diabetes impaired spatial learning and memory of rats. Diabetes decreased the sodium currents and increased the potassium currents, and further led to the reduction of excitability of CA1 pyramidal neurons, effects which may contribute to the behavioral deficits. Fish oil dietary supplementation decreased the transient currents and Kv4.2 expression in the hippocampus and partially improved learning performance of diabetic rats. The results of the present study suggested that sodium and potassium currents contributed to the inhibitory effect of diabetes on neuron excitability, further influencing learning and memory processing. Dietary fish oil may modulate the membrane excitability and is a possible strategy for preventing the impairments of diabetes on hippocampal function. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

  1. Exercise barriers and preferences among women and men with multiple sclerosis.

    PubMed

    Asano, Miho; Duquette, Pierre; Andersen, Ross; Lapierre, Yves; Mayo, Nancy E

    2013-03-01

    The primary objective of this study was to estimate the extent to which women and men with MS present different exercise barriers. The secondary objective was to estimate the extent to which women and men with MS present different perceived-health, depressive symptoms, and current exercise routines or preferences. This was a cross sectional survey. 417 people with MS completed a survey of exercise barriers and current exercise routines, perceived-health and depressive symptoms. The top three exercise barriers were: too tired; impairment; and lack of time, regardless of their gender. Regardless of their gender, three times/week and 60 min/session was identified as the most common current exercise structure among physically active participants. The top three currently preferred exercise by men included walking, strengthening/weights and flexibility/stretch exercise. Women reported the same three exercises but flexibility/stretch exercise were slightly more popular than other exercise. Similarities in perceived health status and depressive symptoms were seen between women and men; expect more men were diagnosed with progressive MS (20% higher) than women, leading to a higher rate of men reporting problems with mobility. Women and men with MS differed very little on exercise barriers and current exercise routines, perceived health and depressive symptoms. Even though MS is generally considered a woman's disease, this study did not find a strong need to develop gender specific exercise or physical activity interventions for this population.

  2. Laboratory reconnection experiments

    NASA Astrophysics Data System (ADS)

    Grulke, Olaf

    Laboratory experiments dedicated for the study of magnetic reconnection have been contributed considerably to a more detailed understanding of the involved processes. Their strength is to disentangle parameter dependencies, to diagnose in detail the plasma and field response, and to form an excellent testbed for the validation of numerical simulations. In the present paper recent results obtained from the new cylindrical reconnection experiment VINETA II are presented. The experimental setup allows to independently vary plasma parameters, reconnection drive strength/timescale, and current sheet amplitude. Current research objectives focus on two major scientific issues: Guide field effects on magnetic reconnection and the evolution of electromagnetic fluctuations. The superimposed homogeneous magnetic guide field has a strong influence on the spatiotemporal evolution of the current sheet, predominantly due to magnetic pitch angle effects, which leads to a strong elongation of the sheet along the separatrices and results in axial gradients of the reconnection rates. Within the current sheet, incoherent electromagnetic fluctuations are observed. Their magnetic signature is characterized by a broad spectrum somewhat centered around the lower-hybrid frequency and extremely short spatial correlation lengths being typically smaller than the local ion sound radius. The fluctuation amplitude correlates with the local current density and, thus, for low guide fields, displays also axial gradients. Despite the quantitatively different parameter regime and geometry the basic fluctuation properties are in good agreement with studies conducted at the MRX experiment (PPPL).

  3. Effect of Continuous and Pulsed Current Gas Tungsten Arc Welding on Dissimilar Weldments Between Hastelloy C-276/AISI 321 Austenitic Stainless Steel

    NASA Astrophysics Data System (ADS)

    Sharma, Sumitra; Taiwade, Ravindra V.; Vashishtha, Himanshu

    2017-03-01

    In the present investigation, an attempt has been made to join Hastelloy C-276 nickel-based superalloy and AISI 321 austenitic stainless steel using ERNiCrMo-4 filler. The joints were fabricated by continuous and pulsed current gas tungsten arc welding processes. Experimental studies to ascertain the structure-property co-relationship with or without pulsed current mode were carried out using an optical microscope and scanning electron microscope. Further, the energy-dispersive spectroscope was used to evaluate the extent of microsegregation. The microstructure of fusion zone was obtained as finer cellular dendritic structure for pulsed current mode, whereas columnar structure was formed with small amount of cellular structure for continuous current mode. The scanning electron microscope examination witnessed the existence of migrated grain boundaries at the weld interfaces. Moreover, the presence of secondary phases such as P and μ was observed in continuous current weld joints, whereas they were absent in pulsed current weld joints, which needs to be further characterized. Moreover, pulsed current joints resulted in narrower weld bead, refined morphology, reduced elemental segregation and improved strength of the welded joints. The outcomes of the present investigation would help in obtaining good quality dissimilar joints for industrial applications and AISI 321 ASS being cheaper consequently led to cost-effective design also.

  4. Current Collection from Space Plasmas

    NASA Technical Reports Server (NTRS)

    Singh, Nagendra (Editor); Wright, K. H., Jr. (Editor); Stone, Nobie H. (Editor)

    1990-01-01

    The First Workshop on Current Collection from Space Plasmas was held at the Tom Bevil Center on the campus of The University of Alabama in Huntsville on April 24 to 25, 1989. The intent of the workshop was to assemble experts on various topics related to the problem of current collection for deliberations that would elucidate the present understanding of the overall current collection problem. Papers presented at the workshop are presented.

  5. 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.

  6. Trends in Mediation Analysis in Nursing Research: Improving Current Practice.

    PubMed

    Hertzog, Melody

    2018-06-01

    The purpose of this study was to describe common approaches used by nursing researchers to test mediation models and evaluate them within the context of current methodological advances. MEDLINE was used to locate studies testing a mediation model and published from 2004 to 2015 in nursing journals. Design (experimental/correlation, cross-sectional/longitudinal, model complexity) and analysis (method, inclusion of test of mediated effect, violations/discussion of assumptions, sample size/power) characteristics were coded for 456 studies. General trends were identified using descriptive statistics. Consistent with findings of reviews in other disciplines, evidence was found that nursing researchers may not be aware of the strong assumptions and serious limitations of their analyses. Suggestions for strengthening the rigor of such studies and an overview of current methods for testing more complex models, including longitudinal mediation processes, are presented.

  7. Temperature dependent charge transport in poly(3-hexylthiophene) diodes

    NASA Astrophysics Data System (ADS)

    Rahaman, Abdulla Bin; Sarkar, Atri; Banerjee, Debamalya

    2018-04-01

    In this work, we present charge transport properties of poly(3-hexylthiophene) (P3HT) diodes under dark conditions. Temperature dependent current-voltage (J-V) characteristics shows that charge transport represents a transition from ohomic to trap limited current. The forward current density obeys a power law J˜Vm, m>2 represents the space charge limited current region in presence of traps within the band gap. Frequency dependent conductivity has been studied in a temperature range 150K-473K. The dc conductivity values show Arrhenius like behavior and it gives conductivity activation energy 223 meV. Temperature dependent conductivity indicates a thermodynamic transition of our system.

  8. Heating the sun's lower transition region with fine-scale electric currents

    NASA Technical Reports Server (NTRS)

    Rabin, D.; Moore, R.

    1984-01-01

    Analytical and observational data are presented to show that the lower transition zone, a 100 km thick region at 10,000-200,000 K between the solar chromosphere and corona, is heated by local electric currents. The study was spurred by correlations between the enhanced atmospheric heating and magnetospheric flux in the chromospheric network and active regions. Field aligned current heated flux loops are asserted to mainly reside in and make up most of the transition region. It is shown that thermal conduction from the sides of hot gas columns generated by the current dissipation is the source of the observed temperature distribution in the transition regions.

  9. Experimental Investigation and Optimization of TIG Welding Parameters on Aluminum 6061 Alloy Using Firefly Algorithm

    NASA Astrophysics Data System (ADS)

    Kumar, Rishi; Mevada, N. Ramesh; Rathore, Santosh; Agarwal, Nitin; Rajput, Vinod; Sinh Barad, AjayPal

    2017-08-01

    To improve Welding quality of aluminum (Al) plate, the TIG Welding system has been prepared, by which Welding current, Shielding gas flow rate and Current polarity can be controlled during Welding process. In the present work, an attempt has been made to study the effect of Welding current, current polarity, and shielding gas flow rate on the tensile strength of the weld joint. Based on the number of parameters and their levels, the Response Surface Methodology technique has been selected as the Design of Experiment. For understanding the influence of input parameters on Ultimate tensile strength of weldment, ANOVA analysis has been carried out. Also to describe and optimize TIG Welding using a new metaheuristic Nature - inspired algorithm which is called as Firefly algorithm which was developed by Dr. Xin-She Yang at Cambridge University in 2007. A general formulation of firefly algorithm is presented together with an analytical, mathematical modeling to optimize the TIG Welding process by a single equivalent objective function.

  10. Social phobia in coeliac disease.

    PubMed

    Addolorato, Giovanni; Mirijello, Antonio; D'Angelo, Cristina; Leggio, Lorenzo; Ferrulli, Anna; Vonghia, Luisa; Cardone, Silvia; Leso, Veruscka; Miceli, Antonio; Gasbarrini, Giovanni

    2008-01-01

    A high prevalence of anxiety and depression has been reported in coeliac disease (CD). Although social phobia is included among the anxiety disorders, its presence in CD has never been investigated. The aim of the present study was to evaluate social phobia in CD patients. A total of 40 CD patients were consecutively enrolled in the study. Fifty healthy subjects were studied as controls. Social phobia was assessed by the Liebowitz Social Anxiety Scale (LSAS) and current depression by the modified version of the Zung Self-rating Depression Scale (M-SDS). The percentage of subjects with social phobia was significantly higher in CD patients than in controls (70% versus 16%; p<0.0001), and also when the more severe generalized form was considered (15.0% versus 0%; p=0.006). The percentage of subjects with social phobia was not statistically different between newly diagnosed subjects and patients on a gluten free diet (73.3% versus 68%; p: NS), nor considering its generalized form (7.0% versus 20%; p: NS). Current depression was present in a significantly higher percentage of CD patients in comparison with controls (52.5% versus 8%; p<0.0001). A direct correlation between social phobia and current depression was found in CD patients (r=0.582; p<0.0001). Despite the limited number of cases evaluated, the present study showed a significantly higher prevalence of social phobia in CD patients compared with in healthy subjects. Future studies are needed to clarify the possible social phobia-induced risks such as school and/or work failure in CD patients.

  11. Life cycle assessment of a road safety product made with virgin and recycled HDPE.

    PubMed

    Simões, Carla L; Xará, Susana M; Bernardo, C A

    2011-04-01

    The present study aims at evaluating the potential environmental impact of using recycled high-density polyethylene (HDPE) in the production of an anti-glare lamella (AGL), a road safety device currently manufactured from virgin (not recycled) polymer. The impact was evaluated using the life cycle assessment (LCA) technique and comparing two alternative systems: current AGL, manufactured from virgin HDPE, and optional AGL, made with recycled HDPE obtained from post-consumer packages. The AGL manufacturing phase was found to be responsible for most of the impacts in both systems, with the production of the raw material being the largest contributor for that phase. The present study makes a contribution to the problem of developing value-added products made from post-consumer polymeric recyclates.

  12. Update Direct-Strike Lightning Environment for Stockpile-to-Target Sequence (Second Revision)

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

    Uman, Martin A.; Rakov, V. A.; Elisme, J. O.

    2010-10-05

    The University of Florida has surveyed all relevant publications reporting lightning characteristics and presents here an up-to-date version of the direct-strike lightning environment specifications for nuclear weapons published in 1989 by R. J. Fisher and M. A. Uman. Further, we present functional expressions for current vs. time, current derivative vs. time, second current derivative vs. time, charge transfer vs. time, and action integral (specific energy) vs. time for positive and negative first return strokes, for negative subsequent return strokes, and for positive and negative continuing currents; and we give sets of constants for these functional expressions so that the resultantmore » waveforms exhibit approximately the median and extreme lightning parameters presented in the updated direct strike environment. Fourier transforms of the return stroke current waveforms are presented. The results of our literature survey are included in three Appendices entitled Return Stroke Current, Continuing Current, and Positive Lightning.« less

  13. The Teacher as a Significant Part of Inclusive Education in the Conditions of Czech Schools: Current Opinions of Czech Teachers about the Inclusive Form of Education

    ERIC Educational Resources Information Center

    Šmelová, Eva; Ludíková, Libuše; Petrová, Alena; Souralová, Eva

    2016-01-01

    Inclusive education and related aspects are currently the priorities of the educational policy in the Czech Republic. Should inclusion be successful, it needs to be supported not only by public administration authorities and legislation, but also by schools, families, school authorities and counselling services. The present research study analyses…

  14. 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.

  15. Delayed Intermodal Contingency Affects Young Children's Recognition of Their Current Self

    ERIC Educational Resources Information Center

    Miyazaki, Michiko; Hiraki, Kazuo

    2006-01-01

    This study investigated whether 2-, 3-, and 4-year-olds use their video feedback as a reflection of their current state, even when their feedback was presented with a short temporal delay. In Experiment 1, the effects of 1- and 2-s delayed feedback were examined on an analog of the mark test. In the case of live and 1-s delayed feedback,…

  16. Hypertext Annotation: Effects of Presentation Formats and Learner Proficiency on Reading Comprehension and Vocabulary Learning in Foreign Languages

    ERIC Educational Resources Information Center

    Chen, I-Jung; Yen, Jung-Chuan

    2013-01-01

    This study extends current knowledge by exploring the effect of different annotation formats, namely in-text annotation, glossary annotation, and pop-up annotation, on hypertext reading comprehension in a foreign language and vocabulary acquisition across student proficiencies. User attitudes toward the annotation presentation were also…

  17. Empowerment of Female Students for Participation in the Representative Councils in Jordanian Universities

    ERIC Educational Resources Information Center

    Saleh, Al-Jufout; Ziad, Abu-Hamatteh; Lama, Al-Qaisy

    2008-01-01

    The current article presents an analytical study of female students' participation in the representative councils in various Jordanian Universities. The data-base applied in the present investigation has indicated a clear weak representation of female students in general. The possible reasons, behind this weakness, have been tracked using a…

  18. Presenting Global Warming and Evolution as Public Health Issues to Encourage Acceptance of Scientific Evidence

    ERIC Educational Resources Information Center

    Stover, Shawn K.; McArthur, Laurence B.; Mabry, Michelle L.

    2013-01-01

    Although evidence supporting anthropogenic global warming and evolution by natural selection is considerable, the public does not embrace these concepts. The current study explores the hypothesis that individuals will become more receptive to scientific viewpoints if evidence for evolution and implications of global warming are presented as issues…

  19. Whose Culture and How Far? Culture Presentation in Current Business English Textbook Series

    ERIC Educational Resources Information Center

    Pashmforoosh, Roya; Babaii, Esmat

    2015-01-01

    International business communication is associated with cultural norms of both native and non-native business counterparts. It seems that the study of culture presentation from the perspective of English as a lingua franca in business English textbooks has been rather underexplored. To this end, cultural contents in two internationally distributed…

  20. Application of advanced technologies to future military transports

    NASA Technical Reports Server (NTRS)

    Clark, Rodney L.; Lange, Roy H.; Wagner, Richard D.

    1990-01-01

    Long range military transport technologies are addressed with emphasis of defining the potential benefits of the hybrid laminar flow control (HLFC) concept currently being flight tested. Results of a 1990's global range transport study are presented showing the expected payoff from application of advanced technologies. Technology forecast for military transports is also presented.

  1. Teacher Education Graduates in Ukraine: Current State of Play

    ERIC Educational Resources Information Center

    Mospan, Natalia

    2016-01-01

    This paper presents an analysis of labour market outcomes for Ukrainian graduates with higher education in teaching, based on the survey 2015. Besides, the study investigates the issues of the source of tuition fee, transition period and employment sectors in the labour market. The evidence presented in this article indicates that teacher…

  2. Benchmarking the Quality of Education: Discrepancies and Correspondence between Theory and Practice in 7 European Countries

    ERIC Educational Resources Information Center

    European Educational Research Journal, 2004

    2004-01-01

    This article presents the conclusion of a study that examines the discrepancies and correspondence between theory and practice in seven European countries. This article presents answers to the following research issues: (1) Discrepancies between existing quality concepts implied in the current international indicator publications and actual…

  3. Family Finance Education; An Interdisciplinary Approach. Volume II.

    ERIC Educational Resources Information Center

    Gibbs, Mary S., Ed.; And Others, Eds.

    Volume II of a two-part series related to family finance education provides materials for study and discussion in the 1968 workshop. In Part I, members of the advisory council present their viewpoints concerning an interdisciplinary approach to education in family finance. Part II presents basic and current information related to principal areas…

  4. Supporting Studies on QDRI Project Plan. Report No. 2. Conversion Procedures for Automation.

    ERIC Educational Resources Information Center

    Peirce, James G.; And Others

    This report describes the tasks and related efforts necessary to convert the present Qualitative Developments Requirements Information (QDRI) Program from a clerical operation into an automated information processing system. A description of the QDRI Program is presented whereby current operations, files, procedures, etc. are contrasted to planned…

  5. 1984-2008. Predictions for Higher Education. From the 25th Anniversary Colloquium. [Proceedings].

    ERIC Educational Resources Information Center

    Hardee, Melvene Draheim, Ed.

    Predictions on higher education for 1984-2009 are presented in the proceedings of a colloquium of the Institute for Studies in Higher Education of Florida State University. Presentations were made at the colloquium by 10 graduates of the university whose current positions represent administration-management, instruction, research, and student…

  6. Aversive eye gaze during a speech in virtual environment in patients with social anxiety disorder.

    PubMed

    Kim, Haena; Shin, Jung Eun; Hong, Yeon-Ju; Shin, Yu-Bin; Shin, Young Seok; Han, Kiwan; Kim, Jae-Jin; Choi, Soo-Hee

    2018-03-01

    One of the main characteristics of social anxiety disorder is excessive fear of social evaluation. In such situations, anxiety can influence gaze behaviour. Thus, the current study adopted virtual reality to examine eye gaze pattern of social anxiety disorder patients while presenting different types of speeches. A total of 79 social anxiety disorder patients and 51 healthy controls presented prepared speeches on general topics and impromptu speeches on self-related topics to a virtual audience while their eye gaze was recorded. Their presentation performance was also evaluated. Overall, social anxiety disorder patients showed less eye gaze towards the audience than healthy controls. Types of speech did not influence social anxiety disorder patients' gaze allocation towards the audience. However, patients with social anxiety disorder showed significant correlations between the amount of eye gaze towards the audience while presenting self-related speeches and social anxiety cognitions. The current study confirms that eye gaze behaviour of social anxiety disorder patients is aversive and that their anxiety symptoms are more dependent on the nature of topic.

  7. In-Flight Manual Electronics Repair for Deep-Space Missions

    NASA Technical Reports Server (NTRS)

    Pettegrew, Richard; Easton, John; Struk, Peter; Anderson, Eric

    2007-01-01

    Severe limitations on mass and volume available for spares on long-duration spaceflight missions will require electronics repair to be conducted at the component level, rather than at the sub-assembly level (referred to as Orbital Replacement Unit, or 'ORU'), as is currently the case aboard the International Space Station. Performing reliable component-level repairs in a reduced gravity environment by crew members will require careful planning, and some specialty tools and systems. Additionally, spacecraft systems must be designed to enable such repairs. This paper is an overview of a NASA project which examines all of these aspects of component level electronic repair. Results of case studies that detail how NASA, the U.S. Navy, and a commercial company currently approach electronics repair are presented, along with results of a trade study examining commercial technologies and solutions which may be used in future applications. Initial design recommendations resulting from these studies are also presented.

  8. A survey on sleep assessment methods

    PubMed Central

    Silva, Josep; Cauli, Omar

    2018-01-01

    Purpose A literature review is presented that aims to summarize and compare current methods to evaluate sleep. Methods Current sleep assessment methods have been classified according to different criteria; e.g., objective (polysomnography, actigraphy…) vs. subjective (sleep questionnaires, diaries…), contact vs. contactless devices, and need for medical assistance vs. self-assessment. A comparison of validation studies is carried out for each method, identifying their sensitivity and specificity reported in the literature. Finally, the state of the market has also been reviewed with respect to customers’ opinions about current sleep apps. Results A taxonomy that classifies the sleep detection methods. A description of each method that includes the tendencies of their underlying technologies analyzed in accordance with the literature. A comparison in terms of precision of existing validation studies and reports. Discussion In order of accuracy, sleep detection methods may be arranged as follows: Questionnaire < Sleep diary < Contactless devices < Contact devices < Polysomnography A literature review suggests that current subjective methods present a sensitivity between 73% and 97.7%, while their specificity ranges in the interval 50%–96%. Objective methods such as actigraphy present a sensibility higher than 90%. However, their specificity is low compared to their sensitivity, being one of the limitations of such technology. Moreover, there are other factors, such as the patient’s perception of her or his sleep, that can be provided only by subjective methods. Therefore, sleep detection methods should be combined to produce a synergy between objective and subjective methods. The review of the market indicates the most valued sleep apps, but it also identifies problems and gaps, e.g., many hardware devices have not been validated and (especially software apps) should be studied before their clinical use. PMID:29844990

  9. Fabrication and high temperature characteristics of ion-implanted GaAs bipolar transistors and ring-oscillators

    NASA Technical Reports Server (NTRS)

    Doerbeck, F. H.; Yuan, H. T.; Mclevige, W. V.

    1981-01-01

    Ion implantation techniques that permit the reproducible fabrication of bipolar GaAs integrated circuits are studied. A 15 stage ring oscillator and discrete transistor were characterized between 25 and 400 C. The current gain of the transistor was found to increase slightly with temperature. The diode leakage currents increase with an activation energy of approximately 1 eV and dominate the transistor leakage current 1 sub CEO above 200 C. Present devices fail catastrophically at about 400 C because of Au-metallization.

  10. Examining English Language Learning Motivation of Adult International Learners Studying Abroad in the US

    ERIC Educational Resources Information Center

    Weger, Heather D.

    2013-01-01

    The present study reports on the motivations of adult, international learners of English, studying English 20 hours a week in a US-based Intensive English Program (IEP). Though often used as participants in language acquisition studies, there are few studies of these learners' motivational profiles. In the current study, a questionnaire designed…

  11. Seasonal and nonseasonal variability of satellite-derived surface pigment concentration in the California Current

    NASA Technical Reports Server (NTRS)

    Strub, P. Ted; James, Corinne; Thomas, Andrew C.; Abbott, Mark R.

    1990-01-01

    The large-scale patterns of satellite-derived surface pigment concentration off the west coast of North America are presented and are averaged into monthly mean surface wind fields over the California Current system (CCS) for the July 1979 to June 1986 period. The patterns are discussed in terms of both seasonal and nonseasonal variability for the indicated time period. The large-scale seasonal characteristics of the California Current are summarized. The data and methods used are described, and the problems known to affect the satellite-derived pigment concentrations and the wind data used in the study are discussed. The statistical analysis results are then presented and discussed in light of past observations and theory. Details of the CZCS data processing are described, and details of the principal estimator pattern methodology used here are given.

  12. Charge creation and nucleation of the longitudinal plasma wave in coupled Josephson junctions

    NASA Astrophysics Data System (ADS)

    Shukrinov, Yu. M.; Hamdipour, M.

    2010-11-01

    We study the phase dynamics in coupled Josephson junctions described by a system of nonlinear differential equations. Results of detailed numerical simulations of charge creation in the superconducting layers and the longitudinal plasma wave (LPW) nucleation are presented. We demonstrate the different time stages in the development of the LPW and present the results of FFT analysis at different values of bias current. The correspondence between the breakpoint position on the outermost branch of current voltage characteristics (CVC) and the growing region in time dependence of the electric charge in the superconducting layer is established. The effects of noise in the bias current and the external microwave radiation on the charge dynamics of the coupled Josephson junctions are found. These effects introduce a way to regulate the process of LPW nucleation in the stack of IJJ.

  13. An Adjunct Galilean Satellite Orbiter Using a Small Radioisotope Power Source

    NASA Technical Reports Server (NTRS)

    Abelson, Robert Dean; Randolph, J.; Alkalai, L.; Collins, D.; Moore, W.

    2005-01-01

    This is a conceptual mission study intended to demonstrate the range of possible missions and applications that could be enabled were a new generation of Small Radioisotope Power Systems to be developed by NASA and DOE. While such systems are currently being considered by NASA and DOE, they do not currently exist. This study is one of several small RPS-enabled mission concepts that were studied and presented in the NASA/JPL document "Enabling Exploration with Small Radioisotope Power Systems" available at: http://solarsystem.nasa.gov/multimedia/download-detail.cfm?DL_ID=82

  14. Different approaches to overcome uncertainties of production systems

    NASA Astrophysics Data System (ADS)

    Azizi, Amir; Sorooshian, Shahryar

    2015-05-01

    This study presented a comprehensive review on the understanding of uncertainty and the current approaches that have been proposed to handle the uncertainties in the production systems. This paper classified proposed approaches into 11 groups. The paper studied 114 scholarly papers through various international journals. The paper added the latest findings to the body of knowledge to the current reservoir of understanding of the production uncertainties. Thus, the paper prepared the needs of researchers and practitioners for easy references in this area. This review also provided an excellent source to continue further studies on how to deal with the uncertainties of production system.

  15. The earth's ring current - Present situation and future thrusts

    NASA Technical Reports Server (NTRS)

    Williams, D. J.

    1987-01-01

    Particle distributions, currents, and the ring current situation prior to the August 1984 launch of the AMPTE Charge Composition Explorer (CCE) are discussed. CCE results which demonstrate the capability of these new measurements to pursue questions of ring current sources, energization, and transport are presented. Consideration is given to various ring current generation mechanisms which have been discussed in the literature, and a two-step generation process which to a certain extent unifies the previous mechanisms is presented. The first in-situ global observations of ring current decay as obtained through the detection of energetic neutral atoms generated by charge exchange interactions between the ring current and hydrogen geocorona are discussed, as well as the possibility of using the detection of energetic neutral atoms to obtain global images of the earth's ring current.

  16. Process Evaluation Results from an Environmentally Focused Worksite Weight Management Study

    ERIC Educational Resources Information Center

    DeJoy, David M.; Wilson, Mark G.; Padilla, Heather M.; Goetzel, Ron Z.; Parker, Kristin B.; Della, Lindsay J.; Roemer, Enid C.

    2012-01-01

    There is currently much interest in exploring environmental approaches to combat weight gain and obesity. This study presents process evaluation results from a workplace-based study that tested two levels of environmentally focused weight management interventions in a manufacturing setting. The moderate treatment featured a set of relatively…

  17. Comparative Studies in Special Education.

    ERIC Educational Resources Information Center

    Mazurek, Kas, Ed.; Winzer, Margret A., Ed.

    This text presents 26 case studies which examine special education provisions for children in the world today. The reports focus on the current state of special education in selected nations and major issues and controversies in the field of special education within those nations. Each case study addresses the following themes: (1) prevalence of…

  18. Second Language Grammatical Proficiency and Third Language Acquisition

    ERIC Educational Resources Information Center

    Moghtadi, Laleh; Koosha, Mansour; Lotfi, Ahmad Reza

    2014-01-01

    The main concern of the present study was to investigate the probable correlation between the bilinguals' second language grammatical proficiency level and their third language grammatical proficiency level. The current study was implemented on selecting a total of 100 Iranian female high school students studying at second grade from two…

  19. "JTPE": A 30-Year Retrospective of Published Research

    ERIC Educational Resources Information Center

    Rhoades, Jesse L.; Woods, Amelia M.; Daum, David N.; Ellison, Douglas; Trendowski, Thomas N.

    2016-01-01

    This case study presents an examination of 30 years of "Journal of Teaching in Physical Education" ("JTPE") research. The purpose of this study was to provide a retrospective view of "JTPE" and its contribution to the field of physical education. In this effort the current study employed citation analysis, co-author…

  20. National Cyberethics, Cybersafety, Cybersecurity Baseline Study

    ERIC Educational Resources Information Center

    Education Digest: Essential Readings Condensed for Quick Review, 2009

    2009-01-01

    This article presents findings from a study that explores the nature of the Cyberethics, Cybersafety, and Cybersecurity (C3) educational awareness policies, initiatives, curriculum, and practices currently taking place in the U.S. public and private K-12 educational settings. The study establishes baseline data on C3 awareness, which can be used…

  1. Compendium of JTPA and Related Evaluation Studies.

    ERIC Educational Resources Information Center

    Employment and Training Administration (DOL), Washington, DC.

    This document summarizes the findings of currently available evaluation studies of the Job Training Partnership Act (JTPA) and other related reports and data. Data from 26 studies conducted between 1980 and 1986 are presented under the following subject headings: the state role (monitoring and oversight, policy interpretation and leadership,…

  2. Separating the signal from the noise: Expanding flow cytometry into the sub-micron range.

    EPA Science Inventory

    Cytometry Part A Special Section: Separating the signal from the noise: Expanding flow cytometry into the sub-micron range. The current Cytometry Part A Special Section presents three studies that utilize cytometers to study sub-micron particles. The three studies involve the 1...

  3. 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…

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

    Del Tutto, Marco

    This thesis presents a study of the NuMI beam line intended to clarify how the particle trajectories through the focusing system and consequently the neutrino event yield are affected by the variation of the Horn Currents.

  5. Investigation of Unsteady Flow Behavior in Transonic Compressor Rotors with LES and PIV Measurements

    NASA Technical Reports Server (NTRS)

    Hah, Chunill; Voges, Melanie; Mueller, Martin; Schiffer, Heinz-Peter

    2009-01-01

    In the present study, unsteady flow behavior in a modern transonic axial compressor rotor is studied in detail with large eddy simulation (LES) and particle image velocimetry (PIV). The main purpose of the study is to advance the current understanding of the flow field near the blade tip in an axial transonic compressor rotor near the stall and peak-efficiency conditions. Flow interaction between the tip leakage vortex and the passage shock is inherently unsteady in a transonic compressor. Casing-mounted unsteady pressure transducers have been widely applied to investigate steady and unsteady flow behavior near the casing. Although many aspects of flow have been revealed, flow structures below the casing cannot be studied with casing-mounted pressure transducers. In the present study, unsteady velocity fields are measured with a PIV system and the measured unsteady flow fields are compared with LES simulations. The currently applied PIV measurements indicate that the flow near the tip region is not steady even at the design condition. This self-induced unsteadiness increases significantly as the compressor rotor operates near the stall condition. Measured data from PIV show that the tip clearance vortex oscillates substantially near stall. The calculated unsteady characteristics of the flow from LES agree well with the PIV measurements. Calculated unsteady flow fields show that the formation of the tip clearance vortex is intermittent and the concept of vortex breakdown from steady flow analysis does not seem to apply in the current flow field. Fluid with low momentum near the pressure side of the blade close to the leading edge periodically spills over into the adjacent blade passage. The present study indicates that stall inception is heavily dependent on unsteady behavior of the flow field near the leading edge of the blade tip section for the present transonic compressor rotor.

  6. CURRENT RESEARCH IN SOCIAL STUDIES. BULLETIN OF THE SCHOOL OF EDUCATION, INDIANA UNIVERSITY.

    ERIC Educational Resources Information Center

    MASSIALAS, BYRON G.; SMITH, FREDERICK R.

    THIS REVIEW OF RESEARCH IN SOCIAL STUDIES SUMMARIZES THE MAJOR FINDINGS REPORTED IN THE LITERATURE DURING THE PERIOD 1959-1963. THE RESEARCH DESCRIBED IS PRESENTED UNDER SEVEN DIFFERENT HEADINGS--(1) OBJECTIVES, (2) CURRICULUM, (3) TEACHING SOCIAL STUDIES IN ELEMENTARY SCHOOLS, (4) TEACHING SOCIAL STUDIES IN SECONDARY SCHOOLS, (5) CONTROVERSIAL…

  7. Integrating Learning Outcome Typologies for HRD: Review and Current Status

    ERIC Educational Resources Information Center

    Lim, Doo Hun; Yoon, Seung Won; Park, Sunyoung

    2013-01-01

    This study reports the result of literature review in regards to learning outcome studies and presents a framework that integrates content types with learning outcomes. Analysis of learning outcome studies between 1992 and 2006 using the ERIC database indicated that most empirical studies have assessed the learning outcome at lower levels of…

  8. The current evidence base for the feasibility of 48-hour continuous subcutaneous infusions (CSCIs): A systematically-structured review

    PubMed Central

    Dickman, Andrew; Mason, Stephen; Ellershaw, John

    2018-01-01

    Background A continuous subcutaneous infusion (CSCI) is an effective method of multiple drug administration commonly encountered in end of life care when the oral route is compromised. At present, current practice is to limit syringe driver infusion time to a maximum of 24 hours as dictated by available chemical stability data. However, the ability to deliver prescribed medication by a CSCI over 48 hours may have numerous benefits in both patient care and health service resource utilisation. Aim To examine and present the current evidence base for the stability of 48-hour multiple-drug CSCIs in current clinical practice. Design A systematically-structured review following PRISMA guidelines. Data sources Three electronic databases and the grey literature were searched with no time limits. Empirical studies reporting data on the chemical stability of continuous subcutaneous infusions or solutions stored in polypropylene syringes were included. Results Twenty-one empirical studies were included in this review reporting chemical compatibility and stability of 32 discrete combinations of twenty-four drugs tested at a variety of different drug concentrations. The majority of combinations reported were assessed as being chemically compatible. The greatest risk of clinically significant chemical degradation was observed with midazolam. Only one study reported the microbiological stability of the solution examined. Conclusions There is currently limited evidence for the physical, chemical and microbiological stability of solutions for continuous subcutaneous infusion over a period of 48 hours. More stability data is required before the use of 48-hour CSCIs can be evaluated for use within clinical practice. PMID:29538455

  9. Comprehensive Truck Size and Weight Study : volume 1 : executive summary

    DOT National Transportation Integrated Search

    2000-08-01

    This report presents results of a comprehensive examination of issues surrounding current Federal truck size : and weight (TS&W) limits and potential impacts of changes to those limits. This is the first comprehensive : TS&W study by the Department s...

  10. Report on Catholic School Leadership: Ten Years Later

    ERIC Educational Resources Information Center

    Schuttloffel, Merylann J.

    2014-01-01

    The current follow-up study to data first presented in 2003 and published in "Report on the Future of Catholic School Leadership," provides the comparisons, analysis, commentary, and some reflections and recommendations on the study implications; useful to individual schools and diocesan leaders.

  11. Intensity coding in electric hearing: Effects of electrode configurations and stimulation waveforms

    PubMed Central

    Chua, Tiffany Elise H.; Bachman, Mark; Zeng, Fan-Gang

    2011-01-01

    Objectives Current cochlear implants typically stimulate the auditory nerve with biphasic pulses and monopolar electrode configurations. Tripolar stimulation can increase spatial selectivity and potentially improve place pitch related perception, but requires higher current levels to elicit the same loudness as monopolar stimulation. The present study combined delayed pseudomonophonasic pulses, which produce lower thresholds, with tripolar stimulation in an attempt to solve the power-performance tradeoff problem. Design The present study systematically measured thresholds, dynamic range, loudness growth, and intensity discrimination using either biphasic or delayed pseudomonophonasic pulses under both monopolar and tripolar stimulation. Participants were 5 Clarion cochlear implant users. For each subject, data from apical, middle and basal electrode positions were collected when possible. Results Compared with biphasic pulses, delayed pseudomonophonasic pulses increased the dynamic range by lowering thresholds while maintaining comparable maximum allowable levels under both electrode configurations. However, delayed pseudomonophonasic pulses did not change the shape of loudness growth function and actually increased intensity discrimination limens, especially at lower current levels. Conclusions The present results indicate that delayed pseudomonophonasic pulses coupled with tripolar stimulation cannot provide significant power savings, nor can it increase the functional dynamic range. Whether this combined stimulation could improve functional spectral resolution remains to be seen. PMID:21610498

  12. Direct current contamination of kilohertz frequency alternating current waveforms.

    PubMed

    Franke, Manfred; Bhadra, Niloy; Bhadra, Narendra; Kilgore, Kevin

    2014-07-30

    Kilohertz frequency alternating current (KHFAC) waveforms are being evaluated in a variety of physiological settings because of their potential to modulate neural activity uniquely when compared to frequencies in the sub-kilohertz range. However, the use of waveforms in this frequency range presents some unique challenges regarding the generator output. In this study we explored the possibility of undesirable contamination of the KHFAC waveforms by direct current (DC). We evaluated current- and voltage-controlled KHFAC waveform generators in configurations that included a capacitive coupling between generator and electrode, a resistive coupling and combinations of capacitive with inductive coupling. Our results demonstrate that both voltage- and current-controlled signal generators can unintentionally add DC-contamination to a KHFAC signal, and that capacitive coupling is not always sufficient to eliminate this contamination. We furthermore demonstrated that high value inductors, placed in parallel with the electrode, can be effective in eliminating DC-contamination irrespective of the type of stimulator, reducing the DC contamination to less than 1 μA. This study highlights the importance of carefully designing the electronic setup used in KHFAC studies and suggests specific testing that should be performed and reported in all studies that assess the neural response to KHFAC waveforms. Published by Elsevier B.V.

  13. Enhanced ergonomics approaches for product design: a user experience ecosystem perspective and case studies.

    PubMed

    Xu, Wei

    2014-01-01

    This paper first discusses the major inefficiencies faced in current human factors and ergonomics (HFE) approaches: (1) delivering an optimal end-to-end user experience (UX) to users of a solution across its solution lifecycle stages; (2) strategically influencing the product business and technology capability roadmaps from a UX perspective and (3) proactively identifying new market opportunities and influencing the platform architecture capabilities on which the UX of end products relies. In response to these challenges, three case studies are presented to demonstrate how enhanced ergonomics design approaches have effectively addressed the challenges faced in current HFE approaches. Then, the enhanced ergonomics design approaches are conceptualised by a user-experience ecosystem (UXE) framework, from a UX ecosystem perspective. Finally, evidence supporting the UXE, the advantage and the formalised process for executing UXE and methodological considerations are discussed. Practitioner Summary: This paper presents enhanced ergonomics approaches to product design via three case studies to effectively address current HFE challenges by leveraging a systematic end-to-end UX approach, UX roadmaps and emerging UX associated with prioritised user needs and usages. Thus, HFE professionals can be more strategic, creative and influential.

  14. A web based tool for storing and visualising data generated within a smart home.

    PubMed

    McDonald, H A; Nugent, C D; Moore, G; Finlay, D D; Hallberg, J

    2011-01-01

    There is a growing need to re-assess the current approaches available to researchers for storing and managing heterogeneous data generated within a smart home environment. In our current work we have developed the homeML Application; a web based tool to support researchers engaged in the area of smart home research as they perform experiments. Within this paper the homeML Application is presented which includes the fundamental components of the homeML Repository and the homeML Toolkit. Results from a usability study conducted by 10 computer science researchers are presented; the initial results of which have been positive.

  15. Omental fibromatosis treated by laparoscopic wide surgical resection

    PubMed Central

    Martin, David; Muradbegovic, Mirza; Andrejevic-Blant, Snezana; Petermann, David; Di Mare, Luca

    2018-01-01

    Summary The current report presents a case of an omental fibromatosis discovered incidentally in a 46-year-old woman with no particular medical history and few symptoms. A surgical biopsy was performed initially, and microscopic examination revealed myofibroblastic proliferation. After additional immunohistochemical and molecular analyses, omental fibromatosis was diagnosed. Omental fibromatosis, also called intra-abdominal desmoid, is a rare and benign tumour but can be locally aggressive. Majority of cases are asymptomatic, and difficult to diagnose based on clinical presentation and radiological investigation. Final diagnosis is usually made on histopathology and immunohistochemistry studies. Surgical wide excision is currently the treatment of choice. PMID:29552447

  16. Analytical Solutions to Backreaction on Cosmic Strings

    NASA Astrophysics Data System (ADS)

    Wachter, Jeremy M.

    2017-08-01

    We present analytical studies of gravitational and electromagnetic backreaction on cosmic strings. For oscillating loops of cosmic string, we present a general argument for how kinks must change; additionally, we apply this general argument to the geometrically simple case of the Garfinkle-Vachaspati loop. Our results suggest that the formation of cusps on loops is delayed, and so we should expect fewer cuspy signatures to be seen in gravitational wave observations. Electromagnetic backreaction we show to reduce currents on a string at least as rapidly as necessary to avoid a paradox, and currents induced on a superconducting straight string will be asymptotically reduced to zero.

  17. Superlattice barrier varactors

    NASA Technical Reports Server (NTRS)

    Raman, C.; Sun, J. P.; Chen, W. L.; Munns, G.; East, J.; Haddad, G.

    1992-01-01

    SBV (Single Barrier Varactor) diodes have been proposed as alternatives to Schottky barrier diodes for harmonic multiplier applications. However, these show a higher current than expected. The excess current is due to X valley transport in the barrier. We present experimental results showing that the use of a superlattice barrier and doping spikes in the GaAs depletion regions on either side of the barrier can reduce the excess current and improve the control of the capacitance vs. voltage characteristic. The experimental results consist of data taken from two types of device structures. The first test structure was used to study the performance of AlAs/GaAs superlattice barriers. The wafer was fabricated into 90 micron diameter mesa diodes and the resulting current vs. voltage characteristics were measured. A 10 period superlattice structure with a total thickness of approximately 400 A worked well as an electron barrier. The structure had a current density of about one A/sq cm at one volt at room temperature. The capacitance variation of these structures was small because of the design of the GaAs cladding layers. The second test structure was used to study cladding layer designs. These wafers were InGaAs and InAlAs layers lattice matched to an InP substrate. The layers have n(+) doping spikes near the barrier to increase the zero bias capacitance and control the shape of the capacitance vs. voltage characteristic. These structures have a capacitance ratio of 5:1 and an abrupt change from maximum to minimum capacitance. The measurements were made at 80 K. Based on the information obtained from these two structures, we have designed a structure that combines the low current density barrier with the improved cladding layers. The capacitance and current-voltage characteristics from this structure are presented.

  18. Transportation properties of a high-current magnetically insulated transmission line and dynamics of the electrode plasma

    NASA Astrophysics Data System (ADS)

    Anan'ev, S. S.; Bakshaev, Yu. L.; Bartov, A. V.; Blinov, P. I.; Dan'ko, S. A.; Zhuzhunashvili, A. I.; Kazakov, E. D.; Kalinin, Yu. G.; Kingsep, A. S.; Korolev, V. D.; Mizhiritskii, V. I.; Smirnov, V. P.; Tkachenko, S. I.; Chernenko, A. S.

    2008-07-01

    Results are presented from experimental studies of a section of a magnetically insulated transmission line (MITL) with a current density of up to 500 MA/cm2 and linear current density of up to 7 MA/cm (the parameters close to those in a fast-Z-pinch-driven fusion reactor projected at Sandia Laboratories). The experiments were performed in the S-300 facility (3 MA, 0.15 Ω, 100 ns). At high linear current densities, the surface of the ohmically heated MITL electrode can explode and a plasma layer can form near the electrode surface. As a result, the MITL can lose its transmission properties due to the shunting of the vacuum gap by the plasma produced. In this series of experiments, the dynamics of the electrode plasma and the dependence of the transmission properties of the MITL on the material and cleanness of the electrode surface were studied. It is shown experimentally that, when the current with a linear density of up to 7 MA/cm begins to flow along a model MITL, the input and output currents differ by less than 10% over a time interval of up to 230 ns for nickel electrodes and up to 350 ns for a line with a gold central electrode. No effect of the oil film present on the electrode surface on the loss of the transmission properties of the line was observed. It is also shown that electron losses insignificantly contribute to the total current balance. The experimental results are compared with calculations of the electrode explosion and the subsequent expansion of the plasma layer. A conclusion is made that the life-time of the model MITL satisfies the requirements imposed on the transmission lines intended for use in the projected thermonuclear reactor.

  19. Cutaneous Allodynia and Its Risk Factors in Korean Patients with Migraine: A Survey of Two Tertiary Care Hospitals.

    PubMed

    Kim, Sun-Young; Park, Sung-Pa

    2016-01-01

    To measure the prevalence of cutaneous allodynia in Korean patients with migraine and to characterize the differential risks of migraine-associated factors and psychiatric disorders in its development. The study included consecutive patients with migraine who visited headache clinics at two tertiary care hospitals. Questionnaires including the 12-item Allodynia Symptom Checklist (ASC-12) and the Migraine Disability Assessment (MIDAS) were administered to the patients. The Mini International Neuropsychiatric Interview-Plus, Version 5.0.0 (MINI), was performed to diagnose current major depressive disorder (MDD) and current generalized anxiety disorder (GAD). To determine the predictive factors of cutaneous allodynia, a two-step logistic regression model was used. A total of 332 patients were eligible for the study. Chronic migraine (CM) was present in 140 patients (42.2%). Current MDD and current GAD were identified in 73 (21.9%) and 59 patients (17.7%), respectively. Cutaneous allodynia was present in 48 patients (14.5%). Univariate analyses indicated that cutaneous allodynia was associated with female gender, CM, medication overuse headache, headache intensity, photophobia, phonophobia, MIDAS grade, current MDD, and current GAD. Multivariate analyses revealed that current MDD was the strongest risk factor for cutaneous allodynia (adjusted odds ratio [AOR] = 4.552; 95% confidence intervals [CI] = 2.300-9.007; P = .000), followed by CM (AOR = 3.666; 95% CI = 1.787-7.521; P = .000) and photophobia (AOR = 2.707; 95% CI = 1.340-5.469; P = .005). Korean patients with migraine have a low prevalence of cutaneous allodynia. Both depression and migraine-associated features are important factors in the occurrence of cutaneous allodynia.

  20. Study of switching electric circuits with DC hybrid breaker, one stage

    NASA Astrophysics Data System (ADS)

    Niculescu, T.; Marcu, M.; Popescu, F. G.

    2016-06-01

    The paper presents a method of extinguishing the electric arc that occurs between the contacts of direct current breakers. The method consists of using an LC type extinguishing group to be optimally sized. From this point of view is presented a theoretical approach to the phenomena that occurs immediately after disconnecting the load and the specific diagrams are drawn. Using these, the elements extinguishing group we can choose. At the second part of the paper there is presented an analyses of the circuit switching process by decomposing the process in particular time sequences. For every time interval there was conceived a numerical simulation model in MATLAB-SIMULINK medium which integrates the characteristic differential equation and plots the capacitor voltage variation diagram and the circuit dumping current diagram.

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

    Gann, Gabriel D. Orebi

    Solar neutrinos offer a unique opportunity to study the interaction of neutrinos with matter, a sensitive search for potential new physics effects, and a probe of solar structure and solar system formation. This paper describes the broad physics program addressed by solar neutrino studies, presents the current suite of experiments programs, and describes several potential future detectors that could address the open questions in this field. This paper is a summary of a talk presented at the Neutrino 2014 conference in Boston.

  2. V/STOL tilt rotor aircraft study. Volume 1: Conceptual design of useful military and/or commercial aircraft

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The conceptual designs of four useful tilt-rotor aircraft for the 1975 to 1980 time period are presented. Parametric studies leading to design point selection are described, and the characteristics and capabilities of each configuration are presented. An assessment is made of current technology status, and additional tilt-rotor research programs are recommended to minimize the time, cost, and risk of development of these vehicles.

  3. Sampling-Based Stochastic Sensitivity Analysis Using Score Functions for RBDO Problems with Correlated Random Variables

    DTIC Science & Technology

    2010-08-01

    a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. a ...SECURITY CLASSIFICATION OF: This study presents a methodology for computing stochastic sensitivities with respect to the design variables, which are the...Random Variables Report Title ABSTRACT This study presents a methodology for computing stochastic sensitivities with respect to the design variables

  4. Science Study For A Low Cost Upper Atmosphere Sounder (LOCUS)

    NASA Astrophysics Data System (ADS)

    Gerber, D.; Swinyard, B. M.; Ellison, B. N.; Siddans, R.; Kerridge, B. J.; Plane, J. M. C.; Feng, W.

    2013-12-01

    We present the findings of an initial science study to define the spectral bands for the proposed Mesosphere / Lower Thermosphere (MLT) sounder LOCUS. The LOCUS mission (Fig 1) uses disruptive technologies to make key MLT species detectable globally by satellite remote sensing for the first time. This presentation summarises the technological and scientific foundation on which the current 4-band Terahertz (THz) and sub- millimetre wave (SMW) instrument configuration was conceived.

  5. Research in the Arts: Proceedings of the Conference on Policy Related Studies of the National Endowment for the Arts (Baltimore, Maryland, December 7-9, 1977).

    ERIC Educational Resources Information Center

    Cwi, David, Ed.

    Summaries are presented of arts research projects and of conference workshops which reviewed the projects. These provide an important stock-taking of currently available data on the arts and review a variety of issues involved in improving the present situation. There are four major sections. The first section presents research on the artistic and…

  6. Transcranial Direct Current Stimulation for Treating Depression in a Patient With Right Hemispheric Dominance: A Case Study.

    PubMed

    Shiozawa, Pedro; da Silva, Mailu Enokibara; Cordeiro, Quirino

    2015-09-01

    We report the case of a 66-year-old male patient with major depressive disorder for the last 6 months. The patient had been diagnosed with dyslexia during childhood and was left-handed. The intervention protocol consisted in 10 consecutive daily transcranial direct current stimulation sessions. However, after 5 days of stimulation, the patient presented with intensification of depressive symptoms and panic attacks. It was hypothetized that the intensification of symptoms may have been due to stimulation protocol itself. Considering the patient was left-handed and presented comorbidity with dyslexia, there was a plausible hypothesis of right hemispheric dominance. This was corroborated by the Edinburgh Handedness Scale. In fact, dyslexic patients present right hemisphere dominance more frequently. The patient also presented a single photon emission computed tomography with a hypoperfusion area over the left posterior parietal lobe. After the patients agreement, a 10-day experimental repetitive transcranial magnetic stimulation low-frequency protocol over the left dorsolateral prefrontal cortex was started to inhibit the area, which was hypothetically hyperactivated following the rationale of right dominance. The patient presented amelioration of depressive and anxious symptoms. Given the hemispheric reversal we show in the present case study, however, it seems that therapies that are beneficial to right-handers could be detrimental to left-handers.

  7. Ukrainian Program for Material Science in Microgravity

    NASA Astrophysics Data System (ADS)

    Fedorov, Oleg

    Ukrainian Program for Material Sciences in Microgravity O.P. Fedorov, Space Research Insti-tute of NASU -NSAU, Kyiv, The aim of the report is to present previous and current approach of Ukrainian research society to the prospect of material sciences in microgravity. This approach is based on analysis of Ukrainian program of research in microgravity, preparation of Russian -Ukrainian experiments on Russian segment of ISS and development of new Ukrainian strategy of space activity for the years 2010-2030. Two parts of issues are discussed: (i) the evolution of our views on the priorities in microgravity research (ii) current experiments under preparation and important ground-based results. item1 The concept of "space industrialization" and relevant efforts in Soviet and post -Soviet Ukrainian research institutions are reviewed. The main topics are: melt supercooling, crystal growing, testing of materials, electric welding and study of near-Earth environment. The anticipated and current results are compared. item 2. The main experiments in the framework of Ukrainian-Russian Research Program for Russian Segment of ISS are reviewed. Flight installations under development and ground-based results of the experiments on directional solidification, heat pipes, tribological testing, biocorrosion study is presented. Ground-based experiments and theoretical study of directional solidification of transparent alloys are reviewed as well as preparation of MORPHOS installation for study of succinonitrile -acetone in microgravity.

  8. Best practices for evaluating the capability of nondestructive evaluation (NDE) and structural health monitoring (SHM) techniques for damage characterization

    NASA Astrophysics Data System (ADS)

    Aldrin, John C.; Annis, Charles; Sabbagh, Harold A.; Lindgren, Eric A.

    2016-02-01

    A comprehensive approach to NDE and SHM characterization error (CE) evaluation is presented that follows the framework of the `ahat-versus-a' regression analysis for POD assessment. Characterization capability evaluation is typically more complex with respect to current POD evaluations and thus requires engineering and statistical expertise in the model-building process to ensure all key effects and interactions are addressed. Justifying the statistical model choice with underlying assumptions is key. Several sizing case studies are presented with detailed evaluations of the most appropriate statistical model for each data set. The use of a model-assisted approach is introduced to help assess the reliability of NDE and SHM characterization capability under a wide range of part, environmental and damage conditions. Best practices of using models are presented for both an eddy current NDE sizing and vibration-based SHM case studies. The results of these studies highlight the general protocol feasibility, emphasize the importance of evaluating key application characteristics prior to the study, and demonstrate an approach to quantify the role of varying SHM sensor durability and environmental conditions on characterization performance.

  9. Test results of 12/18 kA ReBCO coated conductor current leads

    NASA Astrophysics Data System (ADS)

    Kovalev, I. A.; Surin, M. I.; Naumov, A. V.; Novikov, M. S.; Novikov, S. I.; Ilin, A. A.; Polyakov, A. V.; Scherbakov, V. I.; Shutova, D. I.

    2017-07-01

    A pair of hybrid current leads (brass + stacked & soldered ReBCO tapes) rated for 12 kA in steady state and for up to 18 kA at pulsed over current conditions was designed, developed and tested at NRC ;Kurchatov Institute; (NRC ;KI;). During the experiment at LN2 temperature, the current leads (CLs) were successfully charged with 18 kA at 100 A/s ramp rate. To date, as far as we know, this is the highest current capacity achieved for 2G HTS current leads. The feasibility of ;stack-and-soldering technique; for 10 kA+ class coated conductor CLs for accelerators and fusion was demonstrated. This paper gives an overview of the leads design and presents the preliminary test results. Detailed studies of magnetic properties and current sharing process for the stacked and staggered HTS joints are also reported.

  10. Disruption of crystalline structure of Sn3.5Ag induced by electric current

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

    Huang, Han-Chie; Lin, Kwang-Lung, E-mail: matkllin@mail.ncku.edu.tw; Wu, Albert T.

    2016-03-21

    This study presented the disruption of the Sn and Ag{sub 3}Sn lattice structures of Sn3.5Ag solder induced by electric current at 5–7 × 10{sup 3} A/cm{sup 2} with a high resolution transmission electron microscope investigation and electron diffraction analysis. The electric current stressing induced a high degree of strain on the alloy, as estimated from the X-ray diffraction (XRD) peak shift of the current stressed specimen. The XRD peak intensity of the Sn matrix and the Ag{sub 3}Sn intermetallic compound diminished to nearly undetectable after 2 h of current stressing. The electric current stressing gave rise to a high dislocation density ofmore » up to 10{sup 17}/m{sup 2}. The grain morphology of the Sn matrix became invisible after prolonged current stressing as a result of the coalescence of dislocations.« less

  11. A Description of Local Time Asymmetries in the Kronian Current Sheet

    NASA Astrophysics Data System (ADS)

    Nickerson, J. S.; Hansen, K. C.; Gombosi, T. I.

    2012-12-01

    Cassini observations imply that Saturn's magnetospheric current sheet is displaced northward above the rotational equator [C.S. Arridge et al., Warping of Saturn's magnetospheric and magnetotail current sheets, Journal of Geophysical Research, Vol. 113, August 2008]. Arridge et al. show that this hinging of the current sheet above the equator occurs over the noon, midnight, and dawn local time sectors. They present an azimuthally independent model to describe this paraboloid-like geometry. We have used our global MHD model, BATS-R-US/SWMF, to study Saturn's magnetospheric current sheet under various solar wind dynamic pressure and solar zenith angle conditions. We show that under reasonable conditions the current sheet does take on the basic shape of the Arridge model in the noon, midnight, and dawn sectors. However, the hinging distance parameter used in the Arridge model is not a constant and does in fact vary in Saturn local time. We recommend that the Arridge model should be adjusted to account for this azimuthal dependence. Arridge et al. does not discuss the shape of the current sheet in the dusk sector due to an absence of data but does presume that the current sheet will assume the same geometry in this region. On the contrary, our model shows that this is not the case. On the dusk side the current sheet hinges (aggressively) southward and cannot be accounted for by the Arridge model. We will present results from our simulations showing the deviation from axisymmetry and the general behavior of the current sheet under different conditions.

  12. Models in the Design and Validation of Eddy Current Inspection for Cracking in the Shuttle Reaction Control System Thruster

    NASA Technical Reports Server (NTRS)

    Aldrin, John C.; Williams, Phillip A.; Wincheski, Russell (Buzz) A.

    2008-01-01

    A case study is presented for using models in eddy current NDE design for crack detection in Shuttle Reaction Control System thruster components. Numerical methods were used to address the complex geometry of the part and perform parametric studies of potential transducer designs. Simulations were found to show agreement with experimental results. Accurate representation of the coherent noise associated with the measurement and part geometry was found to be critical to properly evaluate the best probe designs.

  13. Electric and hybrid vehicle system R/D

    NASA Technical Reports Server (NTRS)

    Schwartz, H. J.

    1980-01-01

    The work being done to characterize the level of current propulsion technology through component testing is described. Important interactions between the battery and the propulsion system will be discussed. Component development work, involving traction motors, motor controllers and transmissions are described and current results are presented. Studies of advanced electric and hybrid propulsion system studies are summarized and the status of propulsion system development work supported by the project is described. A strategy for fostering joint industry/government projects for commercialization of propulsion components and systems is described briefly.

  14. Resonant pair tunneling in double quantum dots.

    PubMed

    Sela, Eran; Affleck, Ian

    2009-08-21

    We present exact results on the nonequilibrium current fluctuations for 2 quantum dots in series throughout a crossover from non-Fermi liquid to Fermi liquid behavior described by the 2 impurity Kondo model. The result corresponds to resonant tunneling of carriers of charge 2e for a critical interimpurity coupling. At low energy scales, the result can be understood from a Fermi liquid approach that we develop and use to also study nonequilibrium transport in an alternative double dot realization of the 2 impurity Kondo model under current experimental study.

  15. Modeling the process of interaction of 10 keV electrons with a plane dielectric surface

    NASA Astrophysics Data System (ADS)

    Vokhmyanina, Kristina; Sotnikova, Valentina; Sotnikov, Alexey; Kaplii, Anna; Nikulicheva, Tatyana; Kubankin, Alexandr; Kishin, Ivan

    2018-05-01

    The effect of guiding of charged particles by dielectric channels is of noticeable interest at the present time. The phenomenon is widely studied experimentally and theoretically but some points still need to be clarified. A previously developed model of interaction of fast electrons with dielectric surface at grazing incidence is used to study the independence of electron deflection on the value of electron beam current. The calculations were performed assuming a smooth dependence of the surface conductivity on the beam current in the 40-3000 nA range.

  16. Current Evidence Regarding the Diagnostic Methods for Pediatric Lumbar Spondylolisthesis: A Report From the Scoliosis Research Society Evidence Based Medicine Committee.

    PubMed

    Kim, Han Jo; Crawford, Charles H; Ledonio, Charles; Bess, Shay; Larson, A Noelle; Gates, Marilyn; Oetgen, Matthew; Sanders, James O; Burton, Douglas

    Structured literature review. The Scoliosis Research Society (SRS) requested an assessment of the current state of peer-reviewed evidence regarding pediatric lumbar spondylolisthesis with the goal of identifying what is known and what gaps remain in further understanding the diagnostic methods for pediatric spondylolisthesis. Spondylolisthesis in the lumbar spine is common among children and adolescents and no formal synthesis of the published literature regarding diagnostic methods has been previously performed. A comprehensive literature search was performed. Abstracts were reviewed and data from included studies were analyzed by the committee. From 6600 initial citations with abstract, 663 articles underwent full-text review. The best available evidence for the clinical questions regarding diagnostic methods was provided by 26 included studies. Six of the studies were graded as Level III (retrospective comparative), and represent the current best available evidence whereas 20 of the studies were graded as Level IV (retrospective case series) evidence. No Level V (expert opinion) studies were included in the final list. None of the studies were graded as Level I or Level II. Plain radiography is the workhorse imaging modality for diagnosing spondylolisthesis. No association between radiologic grade of spondylolisthesis and clinical presentation were noted; however, grade III and IV slips more often required surgery, and increasing slip angles were associated with worse baseline outcome scores. There is Level III evidence that the Meyerding grade appears to be more accurate for measuring slip percentage whereas the Lonstein Slip angle and Dubousset Lumbosacral Kyphosis angles are the best for measuring lumbosacral kyphosis in spondylolisthesis. In addition, higher sacral table index, pelvic incidence, sacral slope, and lower sacral table angle were associated with spondylolisthesis. True incidence could not be determined by the current literature available. However, studies in adolescent athletes demonstrated an incidence of 6% to 7% across studies. The current "best available" evidence to guide the diagnosis and characterization of pediatric spondylolisthesis is presented. Future studies are needed to provide more high-quality evidence to answer these clinically relevant questions. Level III, review of Level III studies. Copyright © 2017 Scoliosis Research Society. Published by Elsevier Inc. All rights reserved.

  17. Feasibility of a fetal measurement electrode system

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Findings of the study are summarized and conclude that all monitoring requirements are not currently satisfied. An approach is presented to provide a multiparametric monitoring system through combinations of existing transducers. This monitoring system would be appropriate, not only for intrapartum monitoring, but also for neonatal and adult blood gas evaluations. A literature search was conducted to provide an insight into current state-of-the-art in fetal monitoring.

  18. Magnetic properties of CoNiFe alloys electrodeposited under potential and current control conditions

    NASA Astrophysics Data System (ADS)

    Perez, L.; Attenborough, K.; De Boeck, J.; Celis, J. P.; Aroca, C.; Sánchez, P.; López, E.; Sánchez, M. C.

    2002-04-01

    Electrodeposited CoNiFe alloys have been produced under potential and current control conditions. It was found that composition, crystalline structure and magnetic properties are the same irrespective of which plating control is used. Magnetic anisotropy is present in the softest samples. A study of the dependence of magnetic properties and domain structure on the thickness of the films is also reported.

  19. ACE Objectives, Current Status and the 2017 Decadal Survey

    NASA Technical Reports Server (NTRS)

    Da Silva, Arlindo

    2018-01-01

    In this talk we present an overview of the Aerosol-Cloud-Ecosystems (ACE) preformulation studies, a tier-2 satellite mission recommended by the 2007 Decadal Survey. We discuss the current status of ACE measurement concepts and associated retrieval algorithms. We conclude with a brief discussion of the recommendations by the 2017 Decadal Survey and how ACE accomplishments can inform the future Aerosol and Cloud, Convection & Precipitation Designated Observables.

  20. The Social and Economic Status of the Black Population in the United States 1974. Current Population Reports, Special Studies, Series P-23, No. 54.

    ERIC Educational Resources Information Center

    McKenney, Nampeo D.R.; And Others

    This population report presents current census and other governmental and private agency statistics on the demographic, social, and economic characteristics of the black population in the United States for 1974. Recent trends dating from 1970 to 1974 (and in the case of income and labor force, including early 1975 figures) are examined for…

  1. The Lymphatic System and Pancreatic Cancer

    PubMed Central

    Fink, Darci M.; Steele, Maria M.; Hollingsworth, Michael A.

    2016-01-01

    This review summarizes current knowledge of the biology, pathology and clinical understanding of lymphatic invasion and metastasis in pancreatic cancer. We discuss the clinical and biological consequences of lymphatic invasion and metastasis, including paraneoplastic effects on immune responses and consider the possible benefit of therapies to treat tumors that are localized to lymphatics. A review of current techniques and methods to study interactions between tumors and lymphatics is presented. PMID:26742462

  2. Recovery from Gz-induced Loss of Consciousness: Psychophysiologic Considerations

    DTIC Science & Technology

    1988-06-01

    hypnagogic hallucinations). REM activity been considered to occur during REM sleep, non-REM during narcoleptic episodes is usually present at the on...is difficult to ascertain whether the sidered adequate for our purposes. Fig. 3 depicts an "dreams" reported were either " hypnagogic " (as the...necessary. Currently, it is difficult to obtain EEG data in the ac- HYPNAGOGIC HYPNOPOMPIC celeration environment. However, current studies are PERIOD

  3. Remote sensing applications for transportation and traffic engineering studies: A review of the literature

    NASA Technical Reports Server (NTRS)

    Epps, J. W.

    1973-01-01

    Current references were surveyed for the application of remote sensing to traffic and transportation studies. The major problems are presented that concern traffic engineers and transportation managers, and the literature references that discuss remote sensing applications are summarized.

  4. A mobile test facility based on a magnetic cumulative generator to study the stability of the power plants under impact of lightning currents

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

    Shurupov, A. V.; Zavalova, V. E., E-mail: zavalova@fites.ru; Kozlov, A. V.

    The report presents the results of the development and field testing of a mobile test facility based on a helical magnetic cumulative generator (MCGTF). The system is designed for full-scale modeling of lightning currents to study the safety of power plants of any type, including nuclear power plants. Advanced technologies of high-energy physics for solving both engineering and applied problems underlie this pilot project. The energy from the magnetic cumulative generator (MCG) is transferred to a high-impedance load with high efficiency of more than 50% using pulse transformer coupling. Modeling of the dynamics of the MEG that operates in amore » circuit with lumped parameters allows one to apply the law of inductance output during operation of the MCG, thus providing the required front of the current pulse in the load without using any switches. The results of field testing of the MCGTF are presented for both the ground loop and the model load. The ground loop generates a load resistance of 2–4 Ω. In the tests, the ohmic resistance of the model load is 10 Ω. It is shown that the current pulse parameters recorded in the resistive-inductive load are close to the calculated values.« less

  5. Operationally Efficient Propulsion System Study (OEPSS) data book. Volume 1: Generic ground operations data

    NASA Technical Reports Server (NTRS)

    Byrd, Raymond J.

    1990-01-01

    This study was initiated to identify operations problems and cost drivers for current propulsion systems and to identify technology and design approaches to increase the operational efficiency and reduce operations costs for future propulsion systems. To provide readily usable data for the Advance Launch System (ALS) program, the results of the Operationally Efficient Propulsion System Study (OEPSS) were organized into a series of OEPSS Data Books as follows: Volume 1, Generic Ground Operations Data; Volume 2, Ground Operations Problems; Volume 3, Operations Technology; Volume 4, OEPSS Design Concepts; and Volume 5, OEPSS Final Review Briefing, which summarizes the activities and results of the study. This volume presents ground processing data for a generic LOX/LH2 booster and core propulsion system based on current STS experience. The data presented includes: top logic diagram, process flow, activities bar-chart, loaded timelines, manpower requirements in terms of duration, headcount and skill mix per operations and maintenance instruction (OMI), and critical path tasks and durations.

  6. Magnetic Field Observations of Partial Ring Current during Storm Recovery Phase

    NASA Technical Reports Server (NTRS)

    Le, Guan; Russell, C. T.; Slavin, J. A.; Lucek, E. A.

    2007-01-01

    We present results of an extensive survey of the magnetic field observations in the inner magnetosphere using 30 years of magnetospheric magnetic field data from Polar, Cluster, ISEE, and AMPTE/CCE missions. The purpose of this study is to understand the magnetic field evolution during the recovery phase of geomagnetic storms, and its implication to the ring current recovery and loss mechanisms of ring current particles. Our previous work on global ring current distribution [Le et al., 2004] has shown that a significant partial ring current is always present at all Dst levels (regardless of storm phases) even for quiet time ring current. The total current carried by the partial ring current is much stronger than (during stormtime) or at least comparable to (during quiet time) the symmetric ring current. It is now commonly believed that a strong partial ring current is formed during the storm main phase due to the enhanced earthward convection of energetic ions from nightside plasma sheet. But the presence of a strong partial ring current throughout the recovery phase remains controversial. The magnetic field generated by the ring current inflates the inner magnetosphere and causes magnetic field depressions in the equatorial magnetosphere. During the storm recovery phase, we find that the distribution of the equatorial magnetic field depression exhibits similar local time dependence as the ring current distribution obtained from the combined dataset in the earlier study. It shows that a strong partial ring current is a permanent feature throughout the recovery phase. In the early recovery phase, the partial ring current peaks near the dusk terminator as indicated by the peak of the magnetic field depression. As the recovery phase progresses, the partial ring current decays most quickly near the dusk and results in a dusk-to-midnight moving of the peak of the partial ring current. Thus the loss mechanisms work most effectively near the dusk. The magnetic field depression increases the gyroradius of ring current protons to a scale greater or comparable to the thickness of the magnetopause, which increases the chance of ion drift loss near the dusk magnetopause at larger L-shell (L>5). But the drift loss mechanism alone cannot explain the loss of ring current ions especially in the smaller L-shell (L<5). The precipitation loss due to wave-particle interaction is most likely the dominant loss mechanism in the small L-shell as it works most effectively at the same local time.

  7. Miniscrews for orthodontic anchorage: a review of available systems.

    PubMed

    Alkadhimi, Aslam; Al-Awadhi, Ebrahim A

    2018-03-15

    In recent years, extensive research has introduced novel ways of reinforcing orthodontic anchorage using a variety of devices temporarily anchored in bone (miniscrews). Currently, there are numerous manufacturers with different miniscrew designs on the market. The aim of this paper is to discuss the key design features of different miniscrew systems on the market. Furthermore, to present clinical selection criteria of miniscrews in different settings taking into account the determinant factors. Review of the literature was carried out using the following search methods: MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials (CENTRAL). The search was focused on studies published until January 2018. We studied each individual miniscrew from all the identified manufacturers in details. All the features were then summarised and presented as a clinical guideline for the selection of miniscrews. In this article, we reviewed the development of miniscrews and outlined the general design features of miniscrews as well as specific design features of the current miniscrews in the market. Extensive research of the current products was carried out to help clinicians better understand the difference between the various designs of miniscrews that can be used.

  8. Transport and contact-free investigation of REBCO thin film temperature dependent pinning landscapes

    NASA Astrophysics Data System (ADS)

    Sinclair, John; Jaroszynski, Jan; Hu, Xinbo; Santos, Michael

    2013-03-01

    Studies of the pinning mechanisms and landscapes of REBa2Cu3Ox (RE=rare earth elements) thin films have been a topic of study in recent years due to, among other reasons, their ability to introduce nonsuperconducting phases and defects. Here we will focus on REBCO thin films with BaZrO3 nanocolumns and other isotropic defects. The evolution of the dominant pinning mechanisms seems to change as a function of temperature even to the point that samples with similar critical current density properties at high temperatures can have distinctly different properties at low temperatures. Earlier work focused on the angular selectivity of the current density profile, though other properties (such as alpha values) can evolve as well. Characteristic results accentuating this evolution of current density properties will be presented. Challenges exist in evaluating these low temperature properties in high magnetic fields, therefore both transport and contact-free results were be presented to compliment the work. Support for this work is provided by the NHMFL via NSF DRM 0654118.

  9. Study on electrical current variations in electromembrane extraction process: Relation between extraction recovery and magnitude of electrical current.

    PubMed

    Rahmani, Turaj; Rahimi, Atyeh; Nojavan, Saeed

    2016-01-15

    This contribution presents an experimental approach to improve analytical performance of electromembrane extraction (EME) procedure, which is based on the scrutiny of current pattern under different extraction conditions such as using different organic solvents as supported liquid membrane, electrical potentials, pH values of donor and acceptor phases, variable extraction times, temperatures, stirring rates, different hollow fiber lengths and the addition of salts or organic solvents to the sample matrix. In this study, four basic drugs with different polarities were extracted under different conditions with the corresponding electrical current patterns compared against extraction recoveries. The extraction process was demonstrated in terms of EME-HPLC analyses of selected basic drugs. Comparing the obtained extraction recoveries with the electrical current patterns, most cases exhibited minimum recovery and repeatability at the highest investigated magnitude of electrical current. . It was further found that identical current patterns are associated with repeated extraction efficiencies. In other words, the pattern should be repeated for a successful extraction. The results showed completely different electrical currents under different extraction conditions, so that all variable parameters have contributions into the electrical current pattern. Finally, the current patterns of extractions from wastewater, plasma and urine samples were demonstrated. The results indicated an increase in the electrical current when extracting from complex matrices; this was seen to decrease the extraction efficiency. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Current and efficiency of Brownian particles under oscillating forces in entropic barriers

    NASA Astrophysics Data System (ADS)

    Nutku, Ferhat; Aydιner, Ekrem

    2015-04-01

    In this study, considering the temporarily unbiased force and different forms of oscillating forces, we investigate the current and efficiency of Brownian particles in an entropic tube structure and present the numerically obtained results. We show that different force forms give rise to different current and efficiency profiles in different optimized parameter intervals. We find that an unbiased oscillating force and an unbiased temporal force lead to the current and efficiency, which are dependent on these parameters. We also observe that the current and efficiency caused by temporal and different oscillating forces have maximum and minimum values in different parameter intervals. We conclude that the current or efficiency can be controlled dynamically by adjusting the parameters of entropic barriers and applied force. Project supported by the Funds from Istanbul University (Grant No. 45662).

  11. Long-term dose-response studies of inhaled or injected radionuclides. Biennial report, 1 October 1991--30 September 1993

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

    Boecker, B.B.; Muggenburg, B.A.; Miller, S.C.

    This report describes the scientific progress in, and current status of, life-span studies of the long-term health risks in Beagle dogs of chronic irradiation from internally deposited radionuclides or from an external source. The reporting period for this document is the 2-year period from October 1, 1991 through September 30, 1993. Studies that were initiated at three different laboratories (Inhalation Toxicology Research Institute, ITRI, University of Utah, and Argonne National Laboratory, ANL) are presented here because they are being completed at ITRI. All living dogs in the Utah-initiated studies were transferred to the ITRI facility for the remainder of theirmore » life-span observations and measurements in September 1987. This report is the fourth in a series of reports dealing with the current status and progress of both the Utah and ITRI studies. Other life-span studies involving dogs exposed to gamma radiation from an external source were initiated and conducted for many years at ANL. In 1991, the decision was made to discontinue the chronic irradiation of the remaining living dogs and to transfer all remaining dogs to ITRI for care, clinical observations, and pathological observations at death or euthanasia. This report provides the current status of these dogs. Status reports on the Utah and ITRI studies comprise most of this report. The ITRI-related section presents brief statements of project objectives, the general procedures used in these studies, and some study-specific features for each of the 19 studies being conducted with either beta- or alpha-emitting radionuclides. Dose- and effect-modifying factors being addressed in these studies include total dose, dose rate, LET, solubility, nonuniformity of dose, species, age, sex, health status, and mode of exposure. Recent additions to experimental protocols for studies in which dogs are still alive involve the collection and analysis of tumor tissues using currently available molecular biology techniques.« less

  12. How the IMF By induces a By component in the closed magnetosphere and how it leads to asymmetric currents and convection patterns in the two hemispheres

    NASA Astrophysics Data System (ADS)

    Tenfjord, P.; Østgaard, N.; Snekvik, K.; Laundal, K. M.; Reistad, J. P.; Haaland, S.; Milan, S. E.

    2015-11-01

    We used the Lyon-Fedder-Mobarry global magnetohydrodynamics model to study the effects of the interplanetary magnetic field (IMF) By component on the coupling between the solar wind and magnetosphere-ionosphere system. When the IMF reconnects with the terrestrial magnetic field with IMF By≠0, flux transport is asymmetrically distributed between the two hemispheres. We describe how By is induced in the closed magnetosphere on both the dayside and nightside and present the governing equations. The magnetosphere imposes asymmetric forces on the ionosphere, and the effects on the ionospheric flow are characterized by distorted convection cell patterns, often referred to as "banana" and "orange" cell patterns. The flux asymmetrically added to the lobes results in a nonuniform induced By in the closed magnetosphere. By including the dynamics of the system, we introduce a mechanism that predicts asymmetric Birkeland currents at conjugate foot points. Asymmetric Birkeland currents are created as a consequence of y directed tension contained in the return flow. Associated with these currents, we expect fast localized ionospheric azimuthal flows present in one hemisphere but not necessarily in the other. We also present current density measurements from Active Magnetosphere and Planetary Electrodynamics Response Experiment that are consistent with this picture. We argue that the induced By produces asymmetrical Birkeland currents as a consequence of asymmetric stress balance between the hemispheres. Such an asymmetry will also lead to asymmetrical foot points and asymmetries in the azimuthal flow in the ionosphere. These phenomena should therefore be treated in a unified way.

  13. Electrochemical treatment of cetrimonium chloride with boron-doped diamond anodes. A technical and economical approach.

    PubMed

    de Araújo, Brenda R S; Linares León, José J

    2018-05-15

    This study presents the results of the electrochemical degradation of the emulsifier cetrimonium chloride (CTAC) on a boron-doped diamond (BDD) anode under different current densities and flow rates. Higher values of these parameters result in a more rapid removal. Nevertheless, operation at low current reduces the required applied charge and increases the chemical oxygen demand (COD) removal efficiency, as there is less development of ineffective parasitic reactions. On the other hand, high flow rates reduce the required volumetric applied charge and increase the COD removal current efficiency. In order to assist and enrich the study, an economic analysis has been performed. For short expected plant lifespans, operation at low current is advantageous due to the lower investment required, whereas for longer expected lifespans, the operational costs make the lower current densities less costly. High flow rates are always advantageous from a financial point of view. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Electrogenic properties of the Na+/K+ ATPase control transitions between normal and pathological brain states

    PubMed Central

    Krishnan, Giri P.; Filatov, Gregory; Shilnikov, Andrey

    2015-01-01

    Ionic concentrations fluctuate significantly during epileptic seizures. In this study, using a combination of in vitro electrophysiology, computer modeling, and dynamical systems analysis, we demonstrate that changes in the potassium and sodium intra- and extracellular ion concentrations ([K+] and [Na+], respectively) during seizure affect the neuron dynamics by modulating the outward Na+/K+ pump current. First, we show that an increase of the outward Na+/K+ pump current mediates termination of seizures when there is a progressive increase in the intracellular [Na+]. Second, we show that the Na+/K+ pump current is crucial in maintaining the stability of the physiological network state; a reduction of this current leads to the onset of seizures via a positive-feedback loop. We then present a novel dynamical mechanism for bursting in neurons with a reduced Na+/K+ pump. Overall, our study demonstrates the profound role of the current mediated by Na+/K+ ATPase on the stability of neuronal dynamics that was previously unknown. PMID:25589588

  15. Effect of fatigue loading on critical current in stainless steel-laminated DI-BSCCO superconducting composite tape

    NASA Astrophysics Data System (ADS)

    Hojo, M.; Osawa, K.; Adachi, T.; Inoue, Y.; Osamura, K.; Ochiai, S.; Ayai, N.; Hayashi, K.

    2010-11-01

    Tensile strain tolerance of the critical current in (Bi,Pb)2Sr2Ca2Cu3Ox (Bi2223) composite superconductor is dramatically improved when the tape is laminated with stainless steel. For practical applications, it is important to understand whether this reinforcement by lamination is effective under fatigue loading. In the present study, we carried out fatigue tests in LN2 and measured the critical current at the specific fatigue cycles to clarify the strain tolerance of the critical current in stainless steel-laminated drastically innovative Bi2223 (DI-BSCCO®) tapes. The fatigue tests were carried out using a computer-controlled 10 kN servo-hydraulic fatigue testing machine with a load cell capacity of 2.5 kN. Tests under static loading showed that the irreversible stress at which the critical current is reduced by 1% from the original value (tensile stress at Ic/Ic0 = 0.99) was 315 MPa when measured at unloading state. The present fatigue tests results indicated that the critical current was maintained at over 98% of the original value at unloading state after stress cycles of 106 when the static irreversible stress was selected as the maximum stress under fatigue loading. Thus, laminated DI-BSCCO tapes showed excellent mechanical properties even under fatigue loading.

  16. Developmental Neurotoxicology: History and Outline of ...

    EPA Pesticide Factsheets

    The present work provides a brief review of basic concepts in developmental neurotoxicology, as well as current representative testing guidelines for evaluating developmental neurotoxicity (DNT) of xenobiotics. Historically, DNT was initially recognized as a “functional” teratogenicity: the main concern was that prenatal and/or early postnatal exposures to chemicals during critical periods of central nervous system (CNS) development would cause later functional abnormalities of the brain. Current internationally harmonized DNT study guidelines are thus intended to predict adverse effects of test compounds on the developing CNS by observing such postnatal parameters as motor activity, startle response, and learning and memory, as well as neropathological alterations. The reliability of current DNT study guidelines and sensitivity of testing methodologies recommended in these guidelines have been confirmed by retrospective evaluations of the many international and domestic collaborative validation studies in developed nations including Japan. Invited review with brief review of basic concepts in developmental neurotoxicology, as well as current representative testing guidelines for evaluating developmental neurotoxicity (DNT) of xenobiotics.

  17. Evaluation of the William S. Hall Psychiatric Institute Clinical Psychology Internship: a replication and extension.

    PubMed

    Stader, Sandra R; Myers, DeRosset; Forand, Angela Q; Holmes, George R; McNulty, George F; Frey, Linda; Bolton, Staci S

    2010-12-01

    This study extends three earlier investigations involving participants who completed their predoctoral clinical psychology internship at the William S. Hall Psychiatric Institute. Intern graduates (N = 37) evaluated how effectively their internship training prepared them for seven aspects of their current work as practicing psychologists. Participants also rated the relevancy of 24 different internship training experiences to their current work and how much these experiences contributed to their development as clinical psychologists. The present study, in conjunction with the three previous studies, covers most of the 40-year period since the inception of the internship program. Analysis of the current data indicates the internship has improved over time and was deemed an exceptional training experience by its graduates. Findings may be of particular interest to internship directors and faculty interested in improving their training program and those who plan to conduct a self-study to maintain their accreditation for clinical psychology internship.

  18. Evaluation of the Efficacy of Communication-Based Treatments for Autism Spectrum Disorders: A Literature Review

    ERIC Educational Resources Information Center

    Brunner, Debra Lynn; Seung, HyeKyeung

    2009-01-01

    This literature review examines the present level of evidence in support of communication-based treatments for children with autism spectrum disorders. Reviews to date have reported on research published through 2002. The current article included 36 studies published between 2002 and 2007. Best available evidence is presented for seven treatment…

  19. Voices from the Field: Evaluation as Part of a Learning Culture

    ERIC Educational Resources Information Center

    Hoole, Emily; Patterson, Tracy E.

    2008-01-01

    The authors present the argument that evaluation as currently practiced is failing the needs of the social sector, if the goal is to help organizations achieve their mission. Three case studies are presented in which evaluation played a key role in the development of a learning culture within the organization. Each case highlights the positive…

  20. Antarctic news clips, 1991

    NASA Astrophysics Data System (ADS)

    1991-08-01

    Published stories are presented that sample a year's news coverage of Antarctica. The intent is to provide the U.S. Antarctic Program participants with a digest of current issues as presented by a variety of writers and popular publications. The subject areas covered include the following: earth science; ice studies; stratospheric ozone; astrophysics; life science; operations; education; antarctic treaty issues; and tourism

  1. The Use of Picture Prompts and Prompt Delay to Teach Receptive Labeling

    ERIC Educational Resources Information Center

    Vedora, Joseph; Barry, Tiffany

    2016-01-01

    The current study extended research on picture prompts by using them with a progressive prompt delay to teach receptive labeling of pictures to 2 teenagers with autism. The procedure differed from prior research because the auditory stimulus was not presented or was presented only once during the picture-prompt condition. The results indicated…

  2. A Constraint-Based Approach to Acquisition of Word-Final Consonant Clusters in Turkish Children

    ERIC Educational Resources Information Center

    Gokgoz-Kurt, Burcu

    2017-01-01

    The current study provides a constraint-based analysis of L1 word-final consonant cluster acquisition in Turkish child language, based on the data originally presented by Topbas and Kopkalli-Yavuz (2008). The present analysis was done using [?]+obstruent consonant cluster acquisition. A comparison of Gradual Learning Algorithm (GLA) under…

  3. Reynolds number and settling velocity influence for finite-release particle-laden gravity currents in a basin

    NASA Astrophysics Data System (ADS)

    Francisco, E. P.; Espath, L. F. R.; Laizet, S.; Silvestrini, J. H.

    2018-01-01

    Three-dimensional highly resolved Direct Numerical Simulations (DNS) of particle-laden gravity currents are presented for the lock-exchange problem in an original basin configuration, similar to delta formation in lakes. For this numerical study, we focus on gravity currents over a flat bed for which density differences are small enough for the Boussinesq approximation to be valid. The concentration of particles is described in an Eulerian fashion by using a transport equation combined with the incompressible Navier-Stokes equations, with the possibility of particles deposition but no erosion nor re-suspension. The focus of this study is on the influence of the Reynolds number and settling velocity on the development of the current which can freely evolve in the streamwise and spanwise direction. It is shown that the settling velocity has a strong influence on the spatial extent of the current, the sedimentation rate, the suspended mass and the shape of the lobe-and-cleft structures while the Reynolds number is mainly affecting the size and number of vortical structures at the front of the current, and the energy budget.

  4. The effect of current and anticipated body pride and shame on dietary restraint and caloric intake.

    PubMed

    Troop, Nicholas A

    2016-01-01

    Studies have established a link between body shame and eating disorder symptoms and behaviours. However, few have differentiated current feelings of body shame from those anticipated with weight change and none has examined the effects of these on subsequent eating behaviour. In this paper, a measure of body pride and shame was developed (Study 1) for the purposes of using it in a subsequent longitudinal study (Study 2). Two hundred and forty two women were recruited from a university and the general population and participated in Study 1, completing the Body Pride and Shame (BPS) scale either online or offline, as well as a number of validating measures. In Study 2, 40 female students completed the BPS, as well as a measure of dietary restraint, and subsequently recorded their dietary intake everyday for the next seven days. Study 1 identified and validated subscales of current body pride/shame as well as pride/shame that is anticipated were the individual to gain weight or lose weight. In Study 2, over and above levels of dietary restraint, current feelings of body shame predicted eating more calories over the next 7 days while the anticipation of shame with weight gain predicted eating fewer calories. Although previous research has only measured current feelings of body shame, the present studies showed that anticipated shame also impacts on subsequent behaviour. Interventions that regulate anticipated as well as current emotions, and that do not merely challenge cognitions, may be important in changing eating behaviour. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Static and Dynamic Effects of Lateral Carrier Diffusion in Semiconductor Lasers

    NASA Technical Reports Server (NTRS)

    Li, Jian-Zhong; Cheung, Samson H.; Ning, C. Z.; Biegel, Bryan A. (Technical Monitor)

    2002-01-01

    Electron and hole diffusions in the plane of semiconductor quantum wells play an important part in the static and dynamic operations of semiconductor lasers. It is well known that the value of diffusion coefficients affects the threshold pumping current of a semiconductor laser. At the same time, the strength of carrier diffusion process is expected to affect the modulation bandwidth of an AC-modulated laser. It is important not only to investigate the combined DC and AC effects due to carrier diffusion, but also to separate the AC effects from that of the combined effects in order to provide design insights for high speed modulation. In this presentation, we apply a hydrodynamic model developed by the present authors recently from the semiconductor Bloch equations. The model allows microscopic calculation of the lateral carrier diffusion coefficient, which is a nonlinear function of the carrier density and plasma temperature. We first studied combined AC and DC effects of lateral carrier diffusion by studying the bandwidth dependence on diffusion coefficient at a given DC current under small signal modulation. The results show an increase of modulation bandwidth with decrease in the diffusion coefficient. We simultaneously studied the effects of nonlinearity in the diffusion coefficient. To clearly identify how much of the bandwidth increase is a result of decrease in the threshold pumping current for smaller diffusion coefficient, thus an effective increase of DC pumping, we study the bandwidth dependence on diffusion coefficient at a given relative pumping. A detailed comparison of the two cases will be presented.

  6. A Kinetic Study of Microwave Start-up of Tokamak Plasmas

    NASA Astrophysics Data System (ADS)

    du Toit, E. J.; O'Brien, M. R.; Vann, R. G. L.

    2017-07-01

    A kinetic model for studying the time evolution of the distribution function for microwave startup is presented. The model for the distribution function is two dimensional in momentum space, but, for simplicity and rapid calculations, has no spatial dependence. Experiments on the Mega Amp Spherical Tokamak have shown that the plasma current is carried mainly by electrons with energies greater than 70 keV, and effects thought to be important in these experiments are included, i.e. particle sources, orbital losses, the loop voltage and microwave heating, with suitable volume averaging where necessary to give terms independent of spatial dimensions. The model predicts current carried by electrons with the same energies as inferred from the experiments, though the current drive efficiency is smaller.

  7. Surface Passivation of CdZnTe Detector by Hydrogen Peroxide Solution Etching

    NASA Technical Reports Server (NTRS)

    Hayes, M.; Chen, H.; Chattopadhyay, K.; Burger, A.; James, R. B.

    1998-01-01

    The spectral resolution of room temperature nuclear radiation detectors such as CdZnTe is usually limited by the presence of conducting surface species that increase the surface leakage current. Studies have shown that the leakage current can be reduced by proper surface preparation. In this study, we try to optimize the performance of CdZnTe detector by etching the detector with hydrogen peroxide solution as function of concentration and etching time. The passivation effect that hydrogen peroxide introduces have been investigated by current-voltage (I-V) measurement on both parallel strips and metal-semiconductor-metal configurations. The improvements on the spectral response of Fe-55 and 241Am due to hydrogen peroxide treatment are presented and discussed.

  8. Effective utility accommodation : final report.

    DOT National Transportation Integrated Search

    2009-12-08

    The report presents research regarding methods to improve project delivery times and minimize construction delays due to utility coordination by conducting a study of the current best practices used by six (6) similar state transportation departments...

  9. Revisiting Antipsychotic-induced Akathisia: Current Issues and Prospective Challenges

    PubMed Central

    Salem, Haitham; Nagpal, Caesa; Pigott, Teresa; Teixeira, Antonio Lucio

    2017-01-01

    Background: Akathisia continues to be a significant challenge in current neurological and psychiatric practice. Prompt and accurate detection is often difficult and there is a lack of consensus concerning the neurobiological basis of akathisia. No definitive treatment has been established for akathisia despite numerous preclinical and clinical studies. Method: We reviewed antipsychotic-induced akathisia including its clinical presentation, proposed underlying pathophysiology, current and under investigation therapeutic strategies. Conclusion: Despite the initial promise that second generation antipsychotics would be devoid of akathisia effects, this has not been confirmed. Currently, there are limited therapeutic options for the clinical practice and the evidence supporting the most widely used treatments (beta blockers, anticholinergic drugs) is still absent or inconsistent. PMID:27928948

  10. New perspectives on evolutionary medicine: the relevance of microevolution for human health and disease.

    PubMed

    Rühli, Frank Jakobus; Henneberg, Maciej

    2013-04-29

    Evolutionary medicine (EM) is a growing field focusing on the evolutionary basis of human diseases and their changes through time. To date, the majority of EM studies have used pure theories of hominin macroevolution to explain the present-day state of human health. Here, we propose a different approach by addressing more empirical and health-oriented research concerning past, current and future microevolutionary changes of human structure, functions and pathologies. Studying generation-to-generation changes of human morphology that occurred in historical times, and still occur in present-day populations under the forces of evolution, helps to explain medical conditions and warns clinicians that their current practices may influence future humans. Also, analyzing historic tissue specimens such as mummies is crucial in order to address the molecular evolution of pathogens, of the human genome, and their coadaptations.

  11. The Organization of Words and Symbolic Gestures in 18-Month-Olds’ Lexicons: Evidence from a Disambiguation Task

    PubMed Central

    Suanda, Sumarga H.; Namy, Laura L.

    2012-01-01

    Infants’ early communicative repertoires include both words and symbolic gestures. The current study examined the extent to which infants organize words and gestures in a single unified lexicon. As a window into lexical organization, eighteen-month-olds’ (N = 32) avoidance of word-gesture overlap was examined and compared to avoidance of word-word overlap. The current study revealed that when presented with novel words, infants avoided lexical overlap, mapping novel words onto novel objects. In contrast, when presented with novel gestures, infants sought overlap, mapping novel gestures onto familiar objects. The results suggest that infants do not treat words and gestures as equivalent lexical items and that during a period of development when word and symbolic gesture processing share many similarities, important differences also exist between these two symbolic forms. PMID:23539273

  12. Avoiding threat in late adulthood: testing two life span theories of emotion.

    PubMed

    Orgeta, Vasiliki

    2011-07-01

    The purpose of the present research was to explore the time course of age-related attentional biases and the role of emotion regulation as a potential mediator of older adults' performance in an emotion dot probe task. In two studies, younger and older adults (N = 80) completed a visual probe detection task, which presented happy, angry, and sad facial expressions. Across both studies, age influenced attentional responses to angry faces. Results indicated a bias away from angry-related facial emotion information occurring relatively late in attention. Age effects were not attributable to decreasing information processing speed or visuoperceptual function. Current results demonstrated that an age-related attentional preference away from angry facial cues was mediated by efforts to suppress emotion. Findings are discussed in relation to current theories of sociocognitive aging.

  13. Attentional Blink Impairment in Social Anxiety Disorder: Depression Comorbidity Matters

    PubMed Central

    Morrison, Amanda S.; Brozovich, Faith A.; Lakhan-Pal, Shreya; Jazaieri, Hooria; Goldin, Philippe R.; Heimberg, Richard G.; Gross, James J.

    2015-01-01

    Background and Objectives Difficulties with attentional control have long been thought to play a key role in anxiety and depressive disorders. However, the nature and extent of attentional control difficulties in social anxiety disorder (SAD) are not yet well understood. The current study was designed to assess whether attentional control for non-emotional information is impaired in SAD when taking comorbid depression into account. Methods Individuals with SAD and healthy controls (HCs) were administered an attentional blink (AB) task in which they identified number targets in a rapid serial visual presentation stream of letters. Results Individuals with SAD and current comorbid depression exhibited reduced accuracy to identify a target that fell within the AB window after the presentation of a first target compared to individuals with SAD without current comorbid depression, as well as to HCs. The latter two groups did not differ from each other, and the three groups did not differ in accuracy for the second target when it was presented after the AB window. Limitations Although we included two clinical groups and the sample size for the noncomorbid SAD group was large, the comorbid SAD group was relatively small. Conclusions These results suggest that impaired attentional control among individuals with SAD may be limited to those suffering from current comorbid depression. PMID:26370394

  14. Challenges of Conducting a Self-Study Process: Small Two-Year Institutions.

    ERIC Educational Resources Information Center

    Weeks, Richard G., Jr.

    A description is provided of the accreditation self-study process employed by Northwest Community College (NCC), along with a copy of the final self-study report. First, information is presented on how the current college organizational structure was used to conduct the self-study, including explanations of the role of the President's Advisory…

  15. Minorities in Textbooks: A Study of Their Treatment in Social Studies Texts.

    ERIC Educational Resources Information Center

    Kane, Michael B.

    This study of 45 social studies texts widely used in American junior and senior high schools examines the current treatment of Negroes, Jews, and other minorities. It is stated that, despite past criticism of publishers and authors, "a significant number of texts published today continue to present a principally white, Protestant, Anglo-Saxon view…

  16. Intervention Integrity in the Low Countries: Interventions Targeting Social-Emotional Behaviors in the School

    ERIC Educational Resources Information Center

    Taal, Margot; Ekels, Elles; van der Valk, Cindel; van der Molen, Maurits

    2017-01-01

    The current study presents a review of intervention studies conducted in the Low Countries (i.e., The Netherlands and Flanders) focusing on social-emotional behaviors in the school. The primary purpose of this review was to assess whether studies included an operational definition of the intervention under study and reported data on the…

  17. Women's Studies in the United States: A Report to the Ford Foundation.

    ERIC Educational Resources Information Center

    Stimpson, Catherine R.; Cobb, Nina Kressner

    Revealing the amount of work that has been done in women's studies since 1970, the report presents a view of women's studies as it exists today in the United States. The report's broad vision reflects the intellectual vitality and diverse characteristics of the current state of women's studies research, the recommendations for broadening the…

  18. Technology Utilisation in Elementary Schools in Turkey's Capital: A Case Study

    ERIC Educational Resources Information Center

    Karaca, Feride; Can, Gulfidan; Yildirim, Soner

    2013-01-01

    A case study was conducted to explore teachers' current technology use in elementary schools in Ankara, the capital of Turkey. The data were collected through a survey, and participants included 1030 classroom teachers across eight districts. The present study results revealed that significant challenges remain with regard to technology use in the…

  19. Understanding Western Students: Motivations and Benefits for Studying in China

    ERIC Educational Resources Information Center

    English, Alexander S.; Allison, Jessica; Ma, Jian Hong

    2016-01-01

    In the recent years, there has been a rise in the number of Western students who are studying in China. Governments in China, and in other Western nations are expanding relations because China is currently developing world-class higher education institutions (Hennock, 2012). The present study explores motivations, deterrents and benefits of…

  20. A Corpus-Based Study on Turkish Spoken Productions of Bilingual Adults

    ERIC Educational Resources Information Center

    Agçam, Reyhan; Bulut, Adem

    2016-01-01

    The current study investigated whether monolingual adult speakers of Turkish and bilingual adult speakers of Arabic and Turkish significantly differ regarding their spoken productions in Turkish. Accordingly, two groups of undergraduate students studying Turkish Language and Literature at a state university in Turkey were presented two videos on a…

  1. Interagency Depainting Study Status

    NASA Technical Reports Server (NTRS)

    Clark-Ingram, Marceia; Cook, Beth

    1999-01-01

    This document discusses coating removal in general. Sections of this presentation include: regulatory background, the initial parameters of the study, the current parameters of the study, stages in each sequence, preparation of the test specimen, material evaluation testing, chemical stripping, CO2 blasting, Flashjet coating removal, plastic media blasting, sodium bicarbonate wet stripping, water stripping, and wheat starch stripping.

  2. Teaching for Civic Engagement: Lesson Learned from Integrating Positive Psychology and Future Studies

    ERIC Educational Resources Information Center

    Allen, Jeanie K.

    2011-01-01

    Teaching for civic education holds promise for assisting colleges and universities that suggest the promotion of global citizenship in their mission statements. This paper presents the study of a course where readings and activities from the literature of positive psychology were integrated with studies about current global issues and potential…

  3. Pre-Existing Background Knowledge Influences Socioeconomic Differences in Preschoolers' Word Learning and Comprehension

    ERIC Educational Resources Information Center

    Kaefer, Tanya; Neuman, Susan B.; Pinkham, Ashley M.

    2015-01-01

    The goal of the current study is to explore the influence of knowledge on socioeconomic discrepancies in word learning and comprehension. After establishing socioeconomic differences in background knowledge (Study 1), the authors presented children with a storybook that incorporates this knowledge (Study 2). Results indicated that middle-income…

  4. School Memories Situating School

    ERIC Educational Resources Information Center

    Tanggaard, Lene; Nielsen, Klaus

    2013-01-01

    This paper reports the results of an interview study of 18 current and former pupils in the Danish "Folkeskole" (primary and secondary public school) from 1930 up to the present. The aim of the study is to provide a forum for usually unheard voices on the subject of everyday life in school. The study pays special attention to relational…

  5. Methods, Chapter 4

    Treesearch

    L.H. Pardo; E.A. Lilleskov; L.H. Geiser; M.J. Robin-Abbott

    2011-01-01

    We present an up-to-date review of current knowledge relating nitrogen (N) inputs to ecological effects, from published literature, reports, and some recent unpublished studies. Our goal is to summarize research on ecosystems across the United States. We include N gradient, long-term, and fertilizer studies; for fertilizer studies, we focus on those with low N...

  6. Iranian Journal of Language Studies (IJLS). Volume 2, Number 1

    ERIC Educational Resources Information Center

    Salmani-Nodoushan, Mohammad Ali, Ed.

    2008-01-01

    "Iranian Journal of Language Studies" ("IJLS") is devoted to all areas of language and linguistics. Its aim is to present work of current interest in all areas of language study. No particular linguistic theories or scientific trends are favored: scientific quality and scholarly standing are the only criteria applied in the…

  7. Improving Students' Study Habits by Demonstrating the Mnemonic Benefits of Semantic Processing

    ERIC Educational Resources Information Center

    Bugg, Julie M.; DeLosh, Edward L.; McDaniel, Mark A.

    2008-01-01

    This article describes an in-class exercise that illustrates the advantage of semantic over nonsemantic study habits. The exercise includes a survey of students' current study strategies, followed by the presentation of an abbreviated version of Craik and Tulving's(1975) classic levels-of-processing experiment. We observed significant benefits of…

  8. Measuring the Influences That Affect Technological Literacy in Rhode Island High Schools

    ERIC Educational Resources Information Center

    Walach, Michael

    2015-01-01

    This study sampled the current state of technological literacy in Rhode Island high schools using a new instrument, the Technological Literacy Assessment, which was developed for this study. Gender inequalities in technological literacy were discovered, and possible causes and solutions are presented. This study suggests possible next steps for…

  9. Women in Mathematics: A Nested Approach

    ERIC Educational Resources Information Center

    Köse, Emek; Johnson, Angela C.

    2016-01-01

    In this article, we present a case study of a course called Women in Mathematics. Students in the course studied the lives and the mathematical contributions of women mathematicians throughout history, as well as current gender equity issues in the study of mathematics and in mathematical careers. They also mentored 20 middle school girls…

  10. Milgram's Obedience Study: A Contentious Classic Reinterpreted

    ERIC Educational Resources Information Center

    Griggs, Richard A.

    2017-01-01

    Given the many older criticisms of Milgram's obedience study and the more damning recent criticisms based on analyses of materials available in the Milgram archives at Yale, this study has become a contentious classic. Yet, current social psychology textbooks present it as an uncontentious classic, with no coverage of the recent criticisms and…

  11. Decision-Making Casebook for Business and Economics.

    ERIC Educational Resources Information Center

    Tedesco, Paul H., Ed.; And Others

    These teacher developed case studies taken from the business world are presented to help secondary students develop an understanding of economics and of the decision-making process. The studies describe real business situations. All historical and current facts are provided for each of the seven case studies. In the first case, students debate…

  12. State Estimates of Disability in America. Disability Statistics Report 3.

    ERIC Educational Resources Information Center

    LaPlante, Mitchell P.

    This study presents and discusses existing data on disability by state, from the 1980 and 1990 censuses, the Current Population Survey (CPS), and the National Health Interview Survey (NHIS). The study used direct methods for states with large sample sizes and synthetic estimates for states with low sample sizes. The study's highlighted findings…

  13. Case Study of a Research Intervention: The University of Utah's Collaborative Approach.

    ERIC Educational Resources Information Center

    Driscoll, Amy

    A report is presented on the progress of the Applying Research to Teacher Education (ARTE) Research Utilization in Elementary Teacher Education (RUETE) study. The purpose of the study is to develop preservice instruction incorporating current research findings on effective instruction and effective schools and to assess the impact of the…

  14. The role of remote wind forcing in the subinertial current variability in the central and northern parts of the South Brazil Bight

    NASA Astrophysics Data System (ADS)

    Dottori, Marcelo; Castro, Belmiro Mendes

    2018-06-01

    Data analysis of continental shelf currents and coastal sea level, together with the application of a semi-analytical model, are used to estimate the importance of remote wind forcing on the subinertial variability of the current in the central and northern areas of the South Brazil Bight. Results from both the data analysis and from the semi-analytical model are robust in showing subinertial variability that propagates along-shelf leaving the coast to the left in accordance with theoretical studies of Continental Shelf Waves (CSW). Both the subinertial variability observed in along-shelf currents and sea level oscillations present different propagation speeds for the narrow northern part of the SBB ( 6-7 m/s) and the wide central SBB region ( 11 m/s), those estimates being in agreement with the modeled CSW propagation speed. On the inner and middle shelf, observed along-shelf subinertial currents show higher correlation coefficients with the winds located southward and earlier in time than with the local wind at the current meter mooring position and at the time of measurement. The inclusion of the remote (located southwestward) wind forcing improves the prediction of the subinertial currents when compared to the currents forced only by the local wind, since the along-shelf-modeled currents present correlation coefficients with observed along-shelf currents up to 20% higher on the inner and middle shelf when the remote wind is included. For most of the outer shelf, on the other hand, this is not observed since usually, the correlation between the currents and the synoptic winds is not statistically significant.

  15. The role of remote wind forcing in the subinertial current variability in the central and northern parts of the South Brazil Bight

    NASA Astrophysics Data System (ADS)

    Dottori, Marcelo; Castro, Belmiro Mendes

    2018-05-01

    Data analysis of continental shelf currents and coastal sea level, together with the application of a semi-analytical model, are used to estimate the importance of remote wind forcing on the subinertial variability of the current in the central and northern areas of the South Brazil Bight. Results from both the data analysis and from the semi-analytical model are robust in showing subinertial variability that propagates along-shelf leaving the coast to the left in accordance with theoretical studies of Continental Shelf Waves (CSW). Both the subinertial variability observed in along-shelf currents and sea level oscillations present different propagation speeds for the narrow northern part of the SBB ( 6-7 m/s) and the wide central SBB region ( 11 m/s), those estimates being in agreement with the modeled CSW propagation speed. On the inner and middle shelf, observed along-shelf subinertial currents show higher correlation coefficients with the winds located southward and earlier in time than with the local wind at the current meter mooring position and at the time of measurement. The inclusion of the remote (located southwestward) wind forcing improves the prediction of the subinertial currents when compared to the currents forced only by the local wind, since the along-shelf-modeled currents present correlation coefficients with observed along-shelf currents up to 20% higher on the inner and middle shelf when the remote wind is included. For most of the outer shelf, on the other hand, this is not observed since usually, the correlation between the currents and the synoptic winds is not statistically significant.

  16. Local structure studies of materials using pair distribution function analysis

    NASA Astrophysics Data System (ADS)

    Peterson, Joseph W.

    A collection of pair distribution function studies on various materials is presented in this dissertation. In each case, local structure information of interest pushes the current limits of what these studies can accomplish. The goal is to provide insight into the individual material behaviors as well as to investigate ways to expand the current limits of PDF analysis. Where possible, I provide a framework for how PDF analysis might be applied to a wider set of material phenomena. Throughout the dissertation, I discuss 0 the capabilities of the PDF method to provide information pertaining to a material's structure and properties, ii) current limitations in the conventional approach to PDF analysis, iii) possible solutions to overcome certain limitations in PDF analysis, and iv) suggestions for future work to expand and improve the capabilities PDF analysis.

  17. Measurement of internal defects in aluminum using a nano-granular in-gap magnetic sensor

    NASA Astrophysics Data System (ADS)

    Ozawa, T.; Yabukami, S.; Totsuka, J.; Koyama, S.; Hayasaka, J.; Wako, N.; Arai, K. I.

    2015-05-01

    Techniques for identifying defects in metals are very important in a wide variety of manufacturing areas. The present paper reports an eddy current testing method that employs a nano-granular in-gap magnetic sensor (GIGS) to detect internal defects in aluminum boards. The GIGS consists of a tunnel magnetoresistive film with nanometer sized grains and two yokes. In the presence of an external magnetic field, the nano-granular film exhibits only a small change in resistance due to the tunnel magnetoresistive effect. However, by placing it between two yokes, the magnetic flux can be greatly concentrated, thus increasing the change in resistance. The GIGS is a magnetic-field sensor that exploits this principle to achieve enhanced sensitivity. Moreover, because it has a cross-sectional yolk area of just 80 μm × 0.5 μm, it achieves outstanding spatial resolution. In the present study, it is used in combination with an eddy-current method in order to detect internal defects in aluminum. In this method, an excitation coil is used to apply an AC magnetic field perpendicular to the aluminum surface. This induces eddy currents in the metal, which in turn give rise to an AC magnetic field, which is then measured by the GIGS. The presence of defects in the aluminum distorts the eddy current flow, causing a change in the magnitude and distribution of the magnetic field. Such changes can be detected using the GIGS. In the present study, the proposed method was used to successfully detect indentations with diameters of 5 mm on the rear surface of an aluminum plate.

  18. Al embedded MgO barrier MTJ: A first principle study for application in fast and compact STT-MRAMs

    NASA Astrophysics Data System (ADS)

    Yadav, Manoj Kumar; Gupta, Santosh Kumar; Rai, Sanjeev; Pandey, Avinash C.

    2017-03-01

    The first principle comparative study of a novel single Al sheet embedded MgO and pure MgO barrier having Fe electrodes magnetic tunnel junction has been presented. Al embedded MgO is reported to provide enhanced spin polarised tunnelling current due to increase of spin-polarized density of states at Fermi energy in the barrier region. This novel MTJ provides a current density and resistance area (RA) product of 94.497 ×107 A / cm2 and 0.105  Ω - μm2 respectively. With such a low RA product; it allows higher deriving current due to which switching time of magnetization reversal reduces without inducing barrier related breakdowns in non-volatile magnetic random access memories. The low RA product and high current density of the proposed MTJ may have possible applications in integration with existing MOS circuits.

  19. Application of gamma-ray radiography and gravimetric measurements after accelerated corrosion tests of steel embedded in mortar

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

    Duffó, Gustavo, E-mail: duffo@cnea.gov.ar; Consejo Nacional de Investigaciones Científicas y Técnicas; Universidad Nacional de San Martín, Av. Gral. Paz 1499, 1650 San Martín, Buenos Aires

    2015-08-15

    The accelerated corrosion by the impressed current technique is widely used in studies of concrete durability since it has the advantage that tests can be carried out within reasonable periods of time. In the present work the relationship between the applied current density and the resulting damage on the reinforcing steel, by applying optical microscopy, scanning electron microscopy, gamma-ray radiography and gravimetric measurements, was studied by means of the implementation of accelerated corrosion tests on reinforced mortar. The results show that the efficiency of the applied current is between 1 and 77%, regardless of the applied current density, the water/cementmore » ratio and the mortar cover depth of the specimens. The results show the applicability of the gamma-ray radiography technique to detect localized corrosion of steel rebars in laboratory specimens.« less

  20. Transport spin dependent in nanostructures: Current and geometry effect of quantum dots in presence of spin-orbit interaction

    NASA Astrophysics Data System (ADS)

    Paredes-Gutiérrez, H.; Pérez-Merchancano, S. T.; Beltran-Rios, C. L.

    2017-12-01

    In this work, we study the quantum electron transport through a Quantum Dots Structure (QDs), with different geometries, embedded in a Quantum Well (QW). The behaviour of the current through the nanostructure (dot and well) is studied considering the orbital spin coupling of the electrons and the Rashba effect, by means of the second quantization theory and the standard model of Green’s functions. Our results show the behaviour of the current in the quantum system as a function of the electric field, presenting resonant states for specific values of both the external field and the spin polarization. Similarly, the behaviour of the current on the nanostructure changes when the geometry of the QD and the size of the same are modified as a function of the polarization of the electron spin and the potential of quantum confinement.

  1. DSMC Simulations of Hypersonic Flows and Comparison With Experiments

    NASA Technical Reports Server (NTRS)

    Moss, James N.; Bird, Graeme A.; Markelov, Gennady N.

    2004-01-01

    This paper presents computational results obtained with the direct simulation Monte Carlo (DSMC) method for several biconic test cases in which shock interactions and flow separation-reattachment are key features of the flow. Recent ground-based experiments have been performed for several biconic configurations, and surface heating rate and pressure measurements have been proposed for code validation studies. The present focus is to expand on the current validating activities for a relatively new DSMC code called DS2V that Bird (second author) has developed. Comparisons with experiments and other computations help clarify the agreement currently being achieved between computations and experiments and to identify the range of measurement variability of the proposed validation data when benchmarked with respect to the current computations. For the test cases with significant vibrational nonequilibrium, the effect of the vibrational energy surface accommodation on heating and other quantities is demonstrated.

  2. Estimation of Lightning Levels on a Launcher Using a BEM-Compressed Model

    NASA Astrophysics Data System (ADS)

    Silly, J.; Chaigne, B.; Aspas-Puertolas, J.; Herlem, Y.

    2016-05-01

    As development cycles in the space industry are being considerably reduced, it seems mandatory to deploy in parallel fast analysis methods for engineering purposes, but without sacrificing accuracy. In this paper we present the application of such methods to early Phase A-B [1] evaluation of lightning constraints on a launch vehicle.A complete 3D parametric model of a launcher has been thus developed and simulated with a Boundary Element Method (BEM)-frequency simulator (equipped with a low frequency algorithm). The time domain values of the observed currents and fields are obtained by post-treatment using an inverse discrete Fourier transform (IDFT).This model is used for lightning studies, especially the simulation are useful to analyse the influence of lightning injected currents on resulting circulated currents on external cable raceways. The description of the model and some of those results are presented in this article.

  3. Balancing past and present: how experience influences boldness over time in Eurasian perch

    PubMed Central

    Magnhagen, Carin

    2017-01-01

    Abstract Adapting to fluctuating predation conditions is a challenge for prey. By learning through experience, animals may adjust their anti-predator behavior to better reflect current predation risk. Although many studies show experience of predation to alter prey behavior, little is known about how prey rely on such experience over time. By comparing boldness over different temporal scales between individuals of Eurasian perch, either experienced or naïve of predators, we examine how risk is traded based on past and present experience. Differences in predator exposure during the first year of life were found to lead to differences in risk-taking behavior, even after the perch been kept in a predator-free environment for 9 months. However, the response to a potential predator was quickly readjusted after increased experience of current conditions. The results highlight how prey have to balance past experiences of predators against current threat levels. PMID:29491973

  4. Balancing past and present: how experience influences boldness over time in Eurasian perch.

    PubMed

    Hellström, Gustav; Magnhagen, Carin

    2017-04-01

    Adapting to fluctuating predation conditions is a challenge for prey. By learning through experience, animals may adjust their anti-predator behavior to better reflect current predation risk. Although many studies show experience of predation to alter prey behavior, little is known about how prey rely on such experience over time. By comparing boldness over different temporal scales between individuals of Eurasian perch, either experienced or naïve of predators, we examine how risk is traded based on past and present experience. Differences in predator exposure during the first year of life were found to lead to differences in risk-taking behavior, even after the perch been kept in a predator-free environment for 9 months. However, the response to a potential predator was quickly readjusted after increased experience of current conditions. The results highlight how prey have to balance past experiences of predators against current threat levels.

  5. 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.

  6. Design of monocular head-mounted displays for increased indoor firefighting safety and efficiency

    NASA Astrophysics Data System (ADS)

    Wilson, Joel; Steingart, Dan; Romero, Russell; Reynolds, Jessica; Mellers, Eric; Redfern, Andrew; Lim, Lloyd; Watts, William; Patton, Colin; Baker, Jessica; Wright, Paul

    2005-05-01

    Four monocular Head-Mounted Display (HMD) prototypes from the Fire Information and Rescue Equipment (FIRE) project at UC Berkeley are presented. The FIRE project aims to give firefighters a system of information technology tools for safer and more efficient firefighting in large buildings. The paper begins by describing the FIRE project and its use of a custom wireless sensor network (WSN) called SmokeNet for personnel tracking. The project aims to address urban/industrial firefighting procedures in need of improvement. Two "user-needs" studies with the Chicago and Berkeley Fire Departments are briefly presented. The FIRE project"s initial HMD prototype designs are then discussed with regard to feedback from the user-needs studies. These prototypes are evaluated in their potential costs and benefits to firefighters and found to need improvement. Next, some currently available commercial HMDs are reviewed and compared in their cost, performance, and potential for use by firefighters. Feedback from the Berkeley Fire Department user-needs study, in which the initial prototypes were demonstrated, is compiled into a concept selection matrix for the next prototypes. This matrix is used to evaluate a variety of HMDs, including some of the commercial units presented, and to select the best design options. Finally, the current prototypes of the two best design options are presented and discussed.

  7. Safety assessment in plant layout design using indexing approach: implementing inherent safety perspective. Part 2-Domino Hazard Index and case study.

    PubMed

    Tugnoli, Alessandro; Khan, Faisal; Amyotte, Paul; Cozzani, Valerio

    2008-12-15

    The design of layout plans requires adequate assessment tools for the quantification of safety performance. The general focus of the present work is to introduce an inherent safety perspective at different points of the layout design process. In particular, index approaches for safety assessment and decision-making in the early stages of layout design are developed and discussed in this two-part contribution. Part 1 (accompanying paper) of the current work presents an integrated index approach for safety assessment of early plant layout. In the present paper (Part 2), an index for evaluation of the hazard related to the potential of domino effects is developed. The index considers the actual consequences of possible escalation scenarios and scores or ranks the subsequent accident propagation potential. The effects of inherent and passive protection measures are also assessed. The result is a rapid quantification of domino hazard potential that can provide substantial support for choices in the early stages of layout design. Additionally, a case study concerning selection among various layout options is presented and analyzed. The case study demonstrates the use and applicability of the indices developed in both parts of the current work and highlights the value of introducing inherent safety features early in layout design.

  8. Metastasis of ovarian cancer to the breast: A report of two cases and a review of the literature

    PubMed Central

    TEMPFER, CLEMENS B.; EL FIZAZI, NARIMAN; ERGONENC, HASSAN; SOLASS, WIEBKE

    2016-01-01

    Metastasis of ovarian cancer to the breast (MOCB) is a rare event. Clinical presentations of MOCB vary and surgery is the mainstay of treatment. The current study presents two cases of MOCB in women with recurrent ovarian cancer first diagnosed in April 2011 and October 2013, respectively. The patients presented to the clinic with a localized, palpable, painful mass in the upper outer quadrant of the right breast and a centrally localized, palpable, painful mass of the left breast, respectively. Breast sonography and mammography showed a singular, round, homogenous tumor with irregular borders in each case. An ipsilateral enlarged axillary node was palpable in one case. Tumor biopsy revealed an undifferentiated adenocarcinoma of unknown origin in one case and a moderately-differentiated adenocarcinoma suspected to be breast cancer in the other case. Tumor cells were positive for estrogen receptor and paired box 8, and negative for GATA binding protein 3 in the two cases. Palliative mastectomy was performed in one case and lumpectomy with ipsilateral axillary sentinel node biopsy in the other case, and the final histology revealed MOCB in each. The post-operative course of the disease was uneventful and the patients continued with their ovarian cancer-specific chemotherapy. One patient succumbed to disease progression 2 months after breast surgery. The other patient remains alive and is currently undergoing systemic chemotherapy. The current study also presents a review of 110 cases of MOCB identified in a literature search of Pubmed. Data from these studies, including the clinical and histological characteristics of MOCB, and the clinical management and prognosis are discussed. Overall, MOCB is rare, with distinct clinical and histological features. The disease is usually treated with local surgical excision or mastectomy and has a poor prognosis. PMID:27313731

  9. Corrosion Assessment of Steel Bars Used in Reinforced Concrete Structures by Means of Eddy Current Testing

    PubMed Central

    de Alcantara, Naasson P.; da Silva, Felipe M.; Guimarães, Mateus T.; Pereira, Matheus D.

    2015-01-01

    This paper presents a theoretical and experimental study on the use of Eddy Current Testing (ECT) to evaluate corrosion processes in steel bars used in reinforced concrete structures. The paper presents the mathematical basis of the ECT sensor built by the authors; followed by a finite element analysis. The results obtained in the simulations are compared with those obtained in experimental tests performed by the authors. Effective resistances and inductances; voltage drops and phase angles of wound coil are calculated using both; simulated and experimental data; and demonstrate a strong correlation. The production of samples of corroded steel bars; by using an impressed current technique is also presented. The authors performed experimental tests in the laboratory using handmade sensors; and the corroded samples. In the tests four gauges; with five levels of loss-of-mass references for each one were used. The results are analyzed in the light of the loss-of-mass and show a strong linear behavior for the analyzed parameters. The conclusions emphasize the feasibility of the proposed technique and highlight opportunities for future works. PMID:26712754

  10. Corrosion Assessment of Steel Bars Used in Reinforced Concrete Structures by Means of Eddy Current Testing.

    PubMed

    de Alcantara, Naasson P; da Silva, Felipe M; Guimarães, Mateus T; Pereira, Matheus D

    2015-12-24

    This paper presents a theoretical and experimental study on the use of Eddy Current Testing (ECT) to evaluate corrosion processes in steel bars used in reinforced concrete structures. The paper presents the mathematical basis of the ECT sensor built by the authors; followed by a finite element analysis. The results obtained in the simulations are compared with those obtained in experimental tests performed by the authors. Effective resistances and inductances; voltage drops and phase angles of wound coil are calculated using both; simulated and experimental data; and demonstrate a strong correlation. The production of samples of corroded steel bars; by using an impressed current technique is also presented. The authors performed experimental tests in the laboratory using handmade sensors; and the corroded samples. In the tests four gauges; with five levels of loss-of-mass references for each one were used. The results are analyzed in the light of the loss-of-mass and show a strong linear behavior for the analyzed parameters. The conclusions emphasize the feasibility of the proposed technique and highlight opportunities for future works.

  11. The Relationship between Assessment and Alcohol Treatment.

    ERIC Educational Resources Information Center

    Maisto, Stephen A.; Nirenberg, Ted D.

    The matching hypothesis, presented in this study, predicts that designing treatment according to patient characteristics leads to better outcomes. A study was conducted to collect data on current practices of patient-treatment matching in alcohol treatment. A questionnaire was completed by 70 directors of Veterans Administration inpatient alcohol…

  12. Strategic Planning Study Team. Final Report.

    ERIC Educational Resources Information Center

    Tennessee Univ., Chattanooga.

    This final report presents the results of a University of Tennessee at Chattanooga's (UTC) strategic planning study team, which was charged with documenting computerized services currently available and recommending to the UTC administration areas in which new services should be introduced at the university. A questionnaire was administered to…

  13. Studying Diversity in Teacher Education

    ERIC Educational Resources Information Center

    Ball, Arnetha, Ed.; Tyson, Cynthia A., Ed.

    2011-01-01

    "Studying Diversity in Teacher Education" is a collaborative effort by experts seeking to elucidate one of the most important issues facing education today. First, the volume examines historically persistent, yet unresolved issues in teacher education and presents research that is currently being done to address these issues. Second, it…

  14. The Integrated Reader: Literature and EE.

    ERIC Educational Resources Information Center

    Hage, Steve; Daniels, Rosalie

    1996-01-01

    Presents a selection of thematic units focusing on the environment that integrate literature, outdoor education, field studies, and research on current environmental issues. These units are part of a program offered at the School of Environmental Studies in Apple Valley, Minnesota. Authors include Thoreau, Camus, Orwell, Hemingway, Sophocles, and…

  15. Seeking a Multi-Construct Model of Morality

    ERIC Educational Resources Information Center

    McDaniel, Brenda L.; Grice, James W.; Eason, E. Allen

    2010-01-01

    The present study explored a multi-construct model of moral development. Variables commonly seen in the moral development literature, such as family interactions, spiritual life, ascription to various sources of moral authority, empathy, shame, guilt and moral judgement competence, were investigated. Results from the current study support previous…

  16. Inclusion in Early Childhood Education: A Zimbabwean Perspective

    ERIC Educational Resources Information Center

    Majoko, Tawanda

    2017-01-01

    The current study examined Early Childhood Education (ECE) teachers' understanding, attitudes and demographic influences regarding inclusion in ECE. Embedded within inclusive pedagogical philosophy, the present descriptive study draws on a sample of 21 ECE teachers purposively selected from ECE settings in Mashonaland West educational province of…

  17. Seasonal variability of the Canary Current: A numerical study

    NASA Astrophysics Data System (ADS)

    Mason, Evan; Colas, Francois; Molemaker, Jeroen; Shchepetkin, Alexander F.; Troupin, Charles; McWilliams, James C.; Sangrã, Pablo

    2011-06-01

    A high-resolution numerical model study of the Canary Basin in the northeast subtropical Atlantic Ocean is presented. A long-term climatological solution from the Regional Oceanic Modeling System (ROMS) reveals mesoscale variability associated with the Azores and Canary Current systems, the northwest African coastal upwelling, and the Canary Island archipelago. The primary result concerns the Canary Current (CanC) which, in the solution, transports ˜3 Sv southward in line with observations. The simulated CanC has a well-defined path with pronounced seasonal variability. This variability is shown to be mediated by the westward passage of two large annually excited counterrotating anomalous structures that originate at the African coast. The anomalies have a sea surface expression, permitting their validation using altimetry and travel at the phase speed of baroclinic planetary (Rossby) waves. The role of nearshore wind stress curl variability as a generating mechanism for the anomalies is confirmed through a sensitivity experiment forced by low-resolution winds. The resulting circulation is weak in comparison to the base run, but the propagating anomalies are still discernible, so we cannot discount a further role in their generation being played by annual reversals of the large-scale boundary flow that are known to occur along the African margin. An additional sensitivity experiment, where the Azores Current is removed by closing the Strait of Gibraltar presents the same anomalies and CanC behavior as the base run, suggesting that the CanC is rather insensitive to upstream variability from the Azores Current.

  18. Epigenetic Effects of Cadmium [Abstract and Poster 2014] ...

    EPA Pesticide Factsheets

    We have reviewed the literature on in vitro and in vivo experiments as well as human studies on cadmium to understand the epigenetic mechanisms involved in cadmium- induced toxicity and carcinogenicity. This presentation will identify gaps in our current understanding and suggest future studies to further our knowledge. The abstract and poster are to be presented at the 45th Annual Meeting of the Environmental Mutagenesis and Genomics Society (EMGS) to be held from Septmeber 13 to 17, 2014.

  19. Mental health literacy in family caregivers: A comparative analysis.

    PubMed

    Mehrotra, Kanika; Nautiyal, Snigdha; Raguram, Ahalya

    2018-01-01

    The present study was undertaken to examine the current level of mental health literacy in family caregivers and to compare the changes over a 23-year period between 1993 and 2016. The current sample consisted of 60 family caregivers of patients with major mental illness from the in-patient and out-patient departments of NIMHANS, assessed on the Orientation towards Mental Illness Scale (OMI). This was compared with data of 80 family caregivers from previous study done in 1993. Family caregivers in the current study showed a significant positive trend on comparison with the previous study. However, area of abnormal behaviour shows a worsening of negative attitudes. Hopelessness and hypo-functioning, relating to the factor of after-effects of mental illness show no significant difference. While knowledge about mental illnesses can be improved by providing information, this does not automatically translate to integration of the mentally ill in society. Current initiatives need to be matched with specific and sustained efforts to reduce stigma associated with mental illness which have persisted unchanged. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. 5 CFR Appendix A to Subpart C of... - Present Value Conversion Factors for Earlier Commencing Date of Annuities of Current and Former...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Present Value Conversion Factors for Earlier Commencing Date of Annuities of Current and Former Spouses of Deceased Separated Employees A...—Present Value Conversion Factors for Earlier Commencing Date of Annuities of Current and Former Spouses of...

  1. Effective treatment options for musculoskeletal pain in primary care: A systematic overview of current evidence

    PubMed Central

    Hill, Jonathan C.; Foster, Nadine E.; Protheroe, Joanne

    2017-01-01

    Background & aims Musculoskeletal pain, the most common cause of disability globally, is most frequently managed in primary care. People with musculoskeletal pain in different body regions share similar characteristics, prognosis, and may respond to similar treatments. This overview aims to summarise current best evidence on currently available treatment options for the five most common musculoskeletal pain presentations (back, neck, shoulder, knee and multi-site pain) in primary care. Methods A systematic search was conducted. Initial searches identified clinical guidelines, clinical pathways and systematic reviews. Additional searches found recently published trials and those addressing gaps in the evidence base. Data on study populations, interventions, and outcomes of intervention on pain and function were extracted. Quality of systematic reviews was assessed using AMSTAR, and strength of evidence rated using a modified GRADE approach. Results Moderate to strong evidence suggests that exercise therapy and psychosocial interventions are effective for relieving pain and improving function for musculoskeletal pain. NSAIDs and opioids reduce pain in the short-term, but the effect size is modest and the potential for adverse effects need careful consideration. Corticosteroid injections were found to be beneficial for short-term pain relief among patients with knee and shoulder pain. However, current evidence remains equivocal on optimal dose, intensity and frequency, or mode of application for most treatment options. Conclusion This review presents a comprehensive summary and critical assessment of current evidence for the treatment of pain presentations in primary care. The evidence synthesis of interventions for common musculoskeletal pain presentations shows moderate-strong evidence for exercise therapy and psychosocial interventions, with short-term benefits only from pharmacological treatments. Future research into optimal dose and application of the most promising treatments is needed. PMID:28640822

  2. Current transformer model with hysteresis for improving the protection response in electrical transmission systems

    NASA Astrophysics Data System (ADS)

    Matussek, Robert; Dzienis, Cezary; Blumschein, Jörg; Schulte, Horst

    2014-12-01

    In this paper, a generic enhanced protection current transformer (CT) model with saturation effects and transient behavior is presented. The model is used for the purpose of analysis and design of power system protection algorithms. Three major classes of protection CT have been modeled which all take into account the nonlinear inductance with remanence effects. The transient short-circuit currents in power systems are simulated under CT saturation condition. The response of a common power system protection algorithm with respect to robustness to nominal parameter variations and sensitivity against maloperation is demonstrated by simulation studies.

  3. 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.

  4. Signals from flavor changing scalar currents at the future colliders

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

    Atwood, D.; Reina, L.; Soni, A.

    1996-11-22

    We present a general phenomenological analysis of a class of Two Higgs Doublet Models with Flavor Changing Neutral Currents arising at the tree level. The existing constraints mainly affect the couplings of the first two generations of quarks, leaving the possibility for non negligible Flavor Changing couplings of the top quark open. The next generation of lepton and hadron colliders will offer the right environment to study the physics of the top quark and to unravel the presence of new physics beyond the Standard Model. In this context we discuss some interesting signals from Flavor Changing Scalar Neutral Currents.

  5. An advanced EM railgun design

    NASA Astrophysics Data System (ADS)

    Hallse, R. L.; Weiman, S. M.

    1986-11-01

    A progress report is presented from a study of structural design concepts for a large, square-bore, multi-shot railgun. The railgun is to have multi-MA current, a barrel longer than 15 ft, a thermally-managed breech 3 ft long, and pre-stressed internal components. The design, as of early 1986, had a one-piece monolithic circular shell, S-glass/epoxy insulators, and bolt-loaded steel pre-stressed plates. Thermal management is achieved with longitudinal cooling slots with numerous water and air inlets. The device is instrumented for gun current, voltage, bore velocity, magnetic field, rail and armature current, bore dimensions and coolant temperature.

  6. On the current drive capability of low dimensional semiconductors: 1D versus 2D

    DOE PAGES

    Zhu, Y.; Appenzeller, J.

    2015-10-29

    Low-dimensional electronic systems are at the heart of many scaling approaches currently pursuit for electronic applications. Here, we present a comparative study between an array of one-dimensional (1D) channels and its two-dimensional (2D) counterpart in terms of current drive capability. Lastly, our findings from analytical expressions derived in this article reveal that under certain conditions an array of 1D channels can outperform a 2D field-effect transistor because of the added degree of freedom to adjust the threshold voltage in an array of 1D devices.

  7. Investigation on Microstructure and Mechanical Properties of Continuous and Pulsed Current Gas Tungsten Arc Welded alloy 600

    NASA Astrophysics Data System (ADS)

    Srikanth, A.; Manikandan, M.

    2018-02-01

    The present study investigates the microstructure and mechanical properties of joints fabricated by Continuous and pulsed current gas tungsten arc welded alloy 600. Welding was done by autogenous mode. The macro examination was carried out to evaluate the welding defects in the weld joints. Optical and Scanning Electron Microscope (SEM) were performed to assess the microstructural changes in the fusion zone. Energy Dispersive Spectroscopy (EDS) analysis was carried to evaluate the microsegregation of alloying elements in the fusion zone. The tensile test was conducted to assess the strength of the weld joints. The results show that no welding defects were observed in the fusion zones of Continuous and Pulsed current Gas Tungsten Arc Welding. The refined microstructure was found in the pulsed current compared to continuous current mode. Microsegregation was not noticed in the weld grain boundary of continuous and pulsed current mode. The pulsed current shows improved mechanical properties compared to the continuous current mode.

  8. Finite element analysis of gradient z-coil induced eddy currents in a permanent MRI magnet.

    PubMed

    Li, Xia; Xia, Ling; Chen, Wufan; Liu, Feng; Crozier, Stuart; Xie, Dexin

    2011-01-01

    In permanent magnetic resonance imaging (MRI) systems, pulsed gradient fields induce strong eddy currents in the conducting structures of the magnet body. The gradient field for image encoding is perturbed by these eddy currents leading to MR image distortions. This paper presents a comprehensive finite element (FE) analysis of the eddy current generation in the magnet conductors. In the proposed FE model, the hysteretic characteristics of ferromagnetic materials are considered and a scalar Preisach hysteresis model is employed. The developed FE model was applied to study gradient z-coil induced eddy currents in a 0.5 T permanent MRI device. The simulation results demonstrate that the approach could be effectively used to investigate eddy current problems involving ferromagnetic materials. With the knowledge gained from this eddy current model, our next step is to design a passive magnet structure and active gradient coils to reduce the eddy current effects. Copyright © 2010 Elsevier Inc. All rights reserved.

  9. The mechanistic basis for noncompetitive ibogaine inhibition of serotonin and dopamine transporters.

    PubMed

    Bulling, Simon; Schicker, Klaus; Zhang, Yuan-Wei; Steinkellner, Thomas; Stockner, Thomas; Gruber, Christian W; Boehm, Stefan; Freissmuth, Michael; Rudnick, Gary; Sitte, Harald H; Sandtner, Walter

    2012-05-25

    Ibogaine, a hallucinogenic alkaloid proposed as a treatment for opiate withdrawal, has been shown to inhibit serotonin transporter (SERT) noncompetitively, in contrast to all other known inhibitors, which are competitive with substrate. Ibogaine binding to SERT increases accessibility in the permeation pathway connecting the substrate-binding site with the cytoplasm. Because of the structural similarity between ibogaine and serotonin, it had been suggested that ibogaine binds to the substrate site of SERT. The results presented here show that ibogaine binds to a distinct site, accessible from the cell exterior, to inhibit both serotonin transport and serotonin-induced ionic currents. Ibogaine noncompetitively inhibited transport by both SERT and the homologous dopamine transporter (DAT). Ibogaine blocked substrate-induced currents also in DAT and increased accessibility of the DAT cytoplasmic permeation pathway. When present on the cell exterior, ibogaine inhibited SERT substrate-induced currents, but not when it was introduced into the cytoplasm through the patch electrode. Similar to noncompetitive transport inhibition, the current block was not reversed by increasing substrate concentration. The kinetics of inhibitor binding and dissociation, as determined by their effect on SERT currents, indicated that ibogaine does not inhibit by forming a long-lived complex with SERT, but rather binds directly to the transporter in an inward-open conformation. A kinetic model for transport describing the noncompetitive action of ibogaine and the competitive action of cocaine accounts well for the results of the present study.

  10. The Mechanistic Basis for Noncompetitive Ibogaine Inhibition of Serotonin and Dopamine Transporters*

    PubMed Central

    Bulling, Simon; Schicker, Klaus; Zhang, Yuan-Wei; Steinkellner, Thomas; Stockner, Thomas; Gruber, Christian W.; Boehm, Stefan; Freissmuth, Michael; Rudnick, Gary; Sitte, Harald H.; Sandtner, Walter

    2012-01-01

    Ibogaine, a hallucinogenic alkaloid proposed as a treatment for opiate withdrawal, has been shown to inhibit serotonin transporter (SERT) noncompetitively, in contrast to all other known inhibitors, which are competitive with substrate. Ibogaine binding to SERT increases accessibility in the permeation pathway connecting the substrate-binding site with the cytoplasm. Because of the structural similarity between ibogaine and serotonin, it had been suggested that ibogaine binds to the substrate site of SERT. The results presented here show that ibogaine binds to a distinct site, accessible from the cell exterior, to inhibit both serotonin transport and serotonin-induced ionic currents. Ibogaine noncompetitively inhibited transport by both SERT and the homologous dopamine transporter (DAT). Ibogaine blocked substrate-induced currents also in DAT and increased accessibility of the DAT cytoplasmic permeation pathway. When present on the cell exterior, ibogaine inhibited SERT substrate-induced currents, but not when it was introduced into the cytoplasm through the patch electrode. Similar to noncompetitive transport inhibition, the current block was not reversed by increasing substrate concentration. The kinetics of inhibitor binding and dissociation, as determined by their effect on SERT currents, indicated that ibogaine does not inhibit by forming a long-lived complex with SERT, but rather binds directly to the transporter in an inward-open conformation. A kinetic model for transport describing the noncompetitive action of ibogaine and the competitive action of cocaine accounts well for the results of the present study. PMID:22451652

  11. Computer games: a double-edged sword?

    PubMed

    Sun, De-Lin; Ma, Ning; Bao, Min; Chen, Xang-Chuan; Zhang, Da-Ren

    2008-10-01

    Excessive computer game playing (ECGP) has already become a serious social problem. However, limited data from experimental lab studies are available about the negative consequences of ECGP on players' cognitive characteristics. In the present study, we compared three groups of participants (current ECGP participants, previous ECGP participants, and control participants) on a Multiple Object Tracking (MOT) task. The previous ECGP participants performed significantly better than the control participants, which suggested a facilitation effect of computer games on visuospatial abilities. Moreover, the current ECGP participants performed significantly worse than the previous ECGP participants. This more important finding indicates that ECGP may be related to cognitive deficits. Implications of this study are discussed.

  12. Leadership practices and staff nurses' intent to stay: a systematic review.

    PubMed

    Cowden, Tracy; Cummings, Greta; Profetto-McGrath, Joanne

    2011-05-01

    The aim of the present study was to describe the findings of a systematic review of the literature that examined the relationship between managers' leadership practices and staff nurses' intent to stay in their current position. The nursing shortage demands that managers focus on the retention of staff nurses. Understanding the relationship between leadership practices and nurses' intent to stay is fundamental to retaining nurses in the workforce. Published English language articles on leadership practices and staff nurses' intent to stay were retrieved from computerized databases and a manual search. Data extraction and quality assessments were completed for the final 23 research articles. Relational leadership practices influence staff nurses' intentions to remain in their current position. This study supports a positive relationship between transformational leadership, supportive work environments and staff nurses' intentions to remain in their current positions. Incorporating relational leadership theory into management practices will influence nurse retention. Advancing current conceptual models will increase knowledge of intent to stay. Clarifying the distinction between the concepts intent to stay and intent to leave is needed to establish a clear theoretical foundation for further intent to stay research. Nurse managers and leaders who practice relational leadership and ensure quality workplace environments are more likely to retain their staff. The findings of the present study support the claim that leadership practices influence staff nurse retention and builds on intent to stay knowledge. © 2011 The Authors. Journal compilation © 2011 Blackwell Publishing Ltd.

  13. Advances in Time-Distance Helioseismology

    NASA Technical Reports Server (NTRS)

    Duvall, Thomas L., Jr.; Beck, John G.; Gizon, Laurent; Kosovichev, Alexander F.; Oegerle, William (Technical Monitor)

    2002-01-01

    Time-distance helioseismology is a way to measure travel times between surface locations for waves traversing the solar interior. Coupling the travel with an extensive modeling effort has proven to be a powerful tool for measuring flows and other wave speed inhomogeneities in the solar interior. Problems receiving current attention include studying the time variation of the meridional circulation and torsional oscillation and active region emergence and evolution, current results on these topics will be presented.

  14. 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.

  15. Study of Magnetospheric Currents and Resultant Surface Magnetic Variations.

    DTIC Science & Technology

    1980-04-17

    compressed as indicated by solar -wind data, automatically injected a ring current with a strength consistent with the observed Dst. The computed inner...Fig!ire 2?; bottoim panal of Figure 5_. Agreement is very acceptahle. The model overestimated the maximum depression of RX, but by a factor that is well...Contributed Papers Presented at the Solar -Terrestrial Physics Symposium, Innsbruck, 1978. Harel, M., R. A. Wolf, P. H. Reiff and M. Siiddy, Computer

  16. Strategy for standardization of preeclampsia research study design.

    PubMed

    Myatt, Leslie; Redman, Christopher W; Staff, Anne Cathrine; Hansson, Stefan; Wilson, Melissa L; Laivuori, Hannele; Poston, Lucilla; Roberts, James M

    2014-06-01

    Preeclampsia remains a major problem worldwide for mothers and babies. Despite intensive study, we have not been able to improve the management or early recognition of preeclampsia. At least part of this is because of failure to standardize the approach to studying this complex syndrome. It is possible that within the syndrome there may be different phenotypes with pathogenic pathways that differ between the subtypes. The capacity to recognize and to exploit different subtypes is of obvious importance for prediction, prevention, and treatment. We present a strategy for research to study preeclampsia, which will allow discrimination of such possible subtypes and also allow comparison and perhaps combinations of findings in different studies by standardized data and biosample collection. To make studies relevant to current clinical practice, the definition of preeclampsia can be that currently used and accepted. However, more importantly, sufficient data should be collected to allow other diagnostic criteria to be used and applied retrospectively. To that end, we present what we consider to be the minimum requirements for a data set in a study of preeclampsia that will facilitate comparisons. We also present a comprehensive or optimal data set for in-depth investigation of pathophysiology. As we approach the definition of phenotypes of preeclampsia by clinical and biochemical criteria, adherence to standardized protocols will hasten our understanding of the causes of preeclampsia and development of targeted treatment strategies.

  17. Ranolazine inhibits shear sensitivity of endogenous Na+ current and spontaneous action potentials in HL-1 cells

    PubMed Central

    Strege, Peter; Beyder, Arthur; Bernard, Cheryl; Crespo-Diaz, Ruben; Behfar, Atta; Terzic, Andre; Ackerman, Michael; Farrugia, Gianrico

    2012-01-01

    NaV1.5 is a mechanosensitive voltage-gated Na+ channel encoded by the gene SCN5A, expressed in cardiac myocytes and required for phase 0 of the cardiac action potential (AP). In the cardiomyocyte, ranolazine inhibits depolarizing Na+ current and delayed rectifier (IKr) currents. Recently, ranolazine was also shown to be an inhibitor of NaV1.5 mechanosensitivity. Stretch also accelerates the firing frequency of the SA node, and fluid shear stress increases the beating rate of cultured cardiomyocytes in vitro. However, no cultured cell platform exists currently for examination of spontaneous electrical activity in response to mechanical stimulation. In the present study, flow of solution over atrial myocyte-derived HL-1 cultured cells was used to study shear stress mechanosensitivity of Na+ current and spontaneous, endogenous rhythmic action potentials. In voltage-clamped HL-1 cells, bath flow increased peak Na+ current by 14 ± 5%. In current-clamped cells, bath flow increased the frequency and decay rate of AP by 27 ± 12% and 18 ± 4%, respectively. Ranolazine blocked both responses to shear stress. This study suggests that cultured HL-1 cells are a viable in vitro model for detailed study of the effects of mechanical stimulation on spontaneous cardiac action potentials. Inhibition of the frequency and decay rate of action potentials in HL-1 cells are potential mechanisms behind the antiarrhythmic effect of ranolazine. PMID:23018927

  18. Transcranial direct current stimulation for depression in Alzheimer's disease: study protocol for a randomized controlled trial.

    PubMed

    Narita, Zui; Yokoi, Yuma

    2017-06-19

    Patients with Alzheimer's disease frequently elicit neuropsychiatric symptoms as well as cognitive deficits. Above all, depression is one of the most common neuropsychiatric symptoms in Alzheimer's disease but antidepressant drugs have not shown significant beneficial effects on it. Moreover, electroconvulsive therapy has not ensured its safety for potential severe adverse events although it does show beneficial clinical effect. Transcranial direct current stimulation can be the safe alternative of neuromodulation, which applies weak direct electrical current to the brain. Although transcranial direct current stimulation has plausible evidence for its effect on depression in young adult patients, no study has explored it in older subjects with depression in Alzheimer's disease. Therefore, we present a study protocol designed to evaluate the safety and clinical effect of transcranial direct current stimulation on depression in Alzheimer's disease in subjects aged over 65 years. This is a two-arm, parallel-design, randomized controlled trial, in which patients and assessors will be blinded. Subjects will be randomized to either an active or a sham transcranial direct current stimulation group. Participants in both groups will be evaluated at baseline, immediately, and 2 weeks after the intervention. This study investigates the safety and effect of transcranial direct current stimulation that may bring a significant impact on both depression and cognition in patients with Alzheimer's disease, and may be useful to enhance their quality of life. ClinicalTrials.gov, NCT02351388 . Registered on 27 January 2015. Last updated on 30 May 2016.

  19. Acoustic flight test of the Piper Lance

    DOT National Transportation Integrated Search

    1986-12-01

    Research is being conducted to refine current noise regulation of propeller-driven small airplanes. Studies are examining the prospect of a substituting a takeoff procedure of equal stringency for the level flyover certification test presently requir...

  20. Carpooling : Status and Potential

    DOT National Transportation Integrated Search

    1975-06-01

    The report contains the findings of studies conducted to analyze the status and potential of work-trip carpooling as a means of achieving more efficient use of the automobile. Current and estimated maximum potential levels of carpooling are presented...

  1. Positron Computed Tomography: Current State, Clinical Results and Future Trends

    DOE R&D Accomplishments Database

    Schelbert, H. R.; Phelps, M. E.; Kuhl, D. E.

    1980-09-01

    An overview is presented of positron computed tomography: its advantages over single photon emission tomography, its use in metabolic studies of the heart and chemical investigation of the brain, and future trends. (ACR)

  2. A study of cathode erosion in high power arcjets

    NASA Astrophysics Data System (ADS)

    Harris, William Jackson, III

    Cathode erosion continues to be one of the predominant technology concerns for high power arcjets. This study will show that cathode erosion in these devices is significantly affected by several mitigating factors, including propellant composition, propellant flowrate, current level, cathode material, and power supply current ripple. In a series of 50-hour and 100-hour long duration experiments, using a water-cooled 30 kilowatt laboratory arcjet, variations in the steady-state cathode erosion rate were characterized for each of these factors using nitrogen propellant at a fixed arc current of 250 Amperes. A complementary series of measurements was made using hydrogen propellant at an arc current of 100 Amperes. The cold cathode erosion rate was also differentiated from the steady-state cathode erosion rate in a series of multi-start cathode erosion experiments. Results of these measurements are presented, along with an analysis of the significant effects of current ripple on arcjet cathode erosion. As part of this study, over a dozen refractory cathode materials were evaluated to measure their resistance to arcjet cathode erosion. Among the materials tested were W-ThO2(1%, 2%, 4%), poly and mono-crystalline W, W-LaB6, W-La2O3, W-BaO2, W-BaCaAl2O4, W-Y2O3, and ZrB2. Based on these measurements, several critical material properties were identified, such work function, density, porosity, melting point, and evaporation rate. While the majority of the materials failed to outperform traditional W-ThO2, these experimental results are used to develop a parametric model of the arcjet cathode physics. The results of this model, and the results of a finite-element thermal analysis of the arcjet cathode, are presented to better explain the relative performance of the materials tested.

  3. Forecast of jet engine exhaust emissions for future high altitude commercial aircraft

    NASA Technical Reports Server (NTRS)

    Grobman, J.; Ingebo, R. D.

    1974-01-01

    Projected minimum levels of engine exhaust emissions that may be practicably achievable for future commercial aircraft operating at high altitude cruise conditions are presented. The forecasts are based on: (1) current knowledge of emission characteristics of combustors and augmentors; (2) the current status of combustion research in emission reduction technology; (3) predictable trends in combustion systems and operating conditions as required for projected engine designs that are candidates for advanced subsonic or supersonic commercial aircraft. Results are presented for cruise conditions in terms of an emission index, g pollutant/kg fuel. Two sets of engine exhaust emission predictions are presented: the first, based on an independent NASA study and the second, based on the consensus of an ad hoc committee composed of industry, university, and government representatives. The consensus forecasts are in general agreement with the NASA forecasts.

  4. Forecast of jet engine exhaust emissions for future high altitude commercial aircraft

    NASA Technical Reports Server (NTRS)

    Grobman, J.; Ingebo, R. D.

    1974-01-01

    Projected minimum levels of engine exhaust emissions that may be practicably achievable for future commercial aircraft operating at high altitude cruise conditions are presented. The forecasts are based on: (1) current knowledge of emission characteristics of combustors and augmentors; (2) the current status of combustion research in emission reduction technology; and (3) predictable trends in combustion systems and operating conditions as required for projected engine designs that are candidates for advanced subsonic or supersonic commercial aircraft. Results are presented for cruise conditions in terms of an emission index, g pollutant/kg fuel. Two sets of engine exhaust emission predictions are presented: the first, based on an independent NASA study and the second, based on the consensus of an ad hoc committee composed of industry, university, and government representatives. The consensus forecasts are in general agreement with the NASA forecasts.

  5. Childhood Enuresis: Current Diagnostic Formulations, Salient Findings, and Effective Treatment Modalities.

    PubMed

    Thurber, Steven

    2017-06-01

    Enuresis constitutes a frequently encountered problem area for children that may adversely affect social and emotional adjustment. This type of incontinence has been of concern to the human family for centuries. A brief history of enuresis is presented followed by current conceptualizations, diagnostic criteria, prevalence rates and psychiatric comorbidities. Historic notions of causation together with ineffective, sometimes barbaric treatments are then discussed, ending with a presentation of evidence-based treatment modalities, with the urine alarm being an essential element of effective treatment. An intervention termed dry bed training combines the urine alarm with a series of procedures designed in part to reduce relapse potential and should be a primary consideration for implementation by treatment professionals. Finally, a brief case study is presented illustrating special etiological and treatment considerations with juvenile psychiatric patients. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. kW-class diode laser bars

    NASA Astrophysics Data System (ADS)

    Strohmaier, S. G.; Erbert, G.; Meissner-Schenk, A. H.; Lommel, M.; Schmidt, B.; Kaul, T.; Karow, M.; Crump, P.

    2017-02-01

    Progress will be presented on ongoing research into the development of ultra-high power and efficiency bars achieving significantly higher output power, conversion efficiency and brightness than currently commercially available. We combine advanced InAlGaAs/GaAs-based epitaxial structures and novel lateral designs, new materials and superior cooling architectures to enable improved performance. Specifically, we present progress in kilowatt-class 10-mm diode laser bars, where recent studies have demonstrated 880 W continuous wave output power from a 10 mm x 4 mm laser diode bar at 850 A of electrical current and 15°C water temperature. This laser achieves < 60% electro-optical efficiency at 880 W CW output power.

  7. A compendium of fossil marine animal families, 2nd edition

    NASA Technical Reports Server (NTRS)

    Sepkoski, J. J. Jr; Sepkoski JJ, J. r. (Principal Investigator)

    1992-01-01

    A comprehensive listing of 4075 taxonomic families of marine animals known from the fossil record is presented. This listing covers invertebrates, vertebrates, and animal-like protists, gives time intervals of apparent origination and extinction, and provides literature sources for these data. The time intervals are mostly 81 internationally recognized stratigraphic stages; more than half of the data are resolved to one of 145 substage divisions, providing more highly resolved data for studies of taxic macroevolution. Families are classified by order, class, and phylum, reflecting current classifications in the published literature. This compendium is a new edition of the 1982 publication, correcting errors and presenting greater stratigraphic resolution and more current ideas about acceptable families and their classification.

  8. Primary pulmonary NK/T-cell lymphoma: A case report and literature review.

    PubMed

    Qiu, Yajuan; Hou, Junna; Hao, Dexun; Zhang, Dandan

    2018-06-01

    Extranodal natural killer (NK)/T-cell lymphoma (ENKTL) is an aggressive disease with poor prognosis. The lung is a relatively rare site of involvement. The current study presents a case of primary pulmonary ENKTL with fever and dyspnea, mimicking pneumonia and initially treated with empirical antibiotics. The patient demonstrated rapid deterioration and died shortly following diagnosis. To the best of our knowledge, large-scale investigations referring to primary pulmonary ENKTL are not available. As a result, the exact incidence and clinical features of primary pulmonary ENKTL are unknown. In the current report, a literature review is presented to discuss the clinical characteristics, diagnosis, treatment, and prognosis factors of this malignant disease.

  9. 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.

  10. Energy-efficient electric motors study

    NASA Astrophysics Data System (ADS)

    1981-03-01

    A survey conducted of purchasers of integral horsepower polyphase motors measured current knowledge of and awareness of energy efficient motors, decision making criteria, information sources, purchase and usage patterns, and related factors. The data obtained were used for the electric motor market penetration analysis. Additionally, a telephone survey was made. The study also provides analyses of distribution channels, commercialization constraints, and the impacts of government programs and rising energy prices. Study findings, conclusions, and recommendations are presented. Sample questionnaires and copies of letters to respondents are presented in appendices as well as descriptions of the methods used.

  11. Measurements of monopolar and bipolar current spreads using forward-masking with a fixed probe.

    PubMed

    Bingabr, Mohamed G; Espinoza-Varas, Blas; Sigdel, Saroj

    2014-05-01

    This research employed a forward-masking paradigm to estimate the current spread of monopolar (MP) and bipolar (BP) maskers, with current amplitudes adjusted to elicit the same loudness. Since the spatial separation between active and return electrodes is smaller in BP than in MP configurations, the BP current spread is more localized and presumably superior in terms of speech intelligibility. Because matching the loudness requires higher current in BP than in MP stimulation, previous forward-masking studies show that BP current spread is not consistently narrower across subjects or electrodes within a subject. The present forward-masking measures of current spread differ from those of previous studies by using the same BP probe electrode configuration for both MP and BP masker configurations, and adjusting the current levels of the MP and BP maskers so as to match them in loudness. With this method, the estimate of masker current spread would not be contaminated by differences in probe current spread. Forward masking was studied in four cochlear implant patients, two females and two males, with speech recognition scores higher than 50%; that is, their auditory-nerve survival status was more than adequate to carry out the experiments. The data showed that MP and BP masker configurations produce equivalent masking patterns (and current spreads) in three participants. A fourth participant displayed asymmetrical patterns with enhancement rather than masking in some cases, especially when the probe and masker were at the same location. This study showed equivalent masking patterns for MP and BP maskers when the BP masker current amplitude was increased to match the loudness of the MP masker, and the same BP probe configuration is used with both maskers. This finding could help to explain why cochlear implant users often fail to accrue higher speech intelligibility benefit from BP stimulation.

  12. Satellite Ocean Data Tools in the high school classroom.

    NASA Astrophysics Data System (ADS)

    Tweedie, M.; Snyder, H. D.

    2007-12-01

    The NASA-sponsored Ocean Motion website (http://www.oceanmotion.org) documents the story of humankind's interest in and observations of surface currents from the early seafaring Polynesians to present day satellite observations. Ocean surface current patterns impact our lives through their influences on the weather, climate, commerce, natural disasters and sea life. The Ocean Motion web site provides inquiry based, classroom ready materials for high school teachers and students to study ocean surface currents. In addition to the information resources posted on the website, there are also investigations that lead students to explore patterns and relationships through data products (color- coded map images, time series graphs and data tables). These investigations are done through an interactive browser interface that provides access to a wealth of oceanography data. This presentation focuses on use of surface current data and models in student investigations to illustrate application of basic science principles found in high school science curriculum. Skills developed using data to discover patterns and relationships will serve students in other courses as well as empower them to become stewards of the Earths environment.

  13. 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

  14. Outside Mainstream Electronic Databases: Review of Studies Conducted in the USSR and Post-Soviet Countries on Electric Current-Assisted Consolidation of Powder Materials

    PubMed Central

    Olevsky, Eugene A.; Aleksandrova, Elena V.; Ilyina, Alexandra M.; Dudina, Dina V.; Novoselov, Alexander N.; Pelve, Kirill Y.; Grigoryev, Eugene G.

    2013-01-01

    This paper reviews research articles published in the former USSR and post-soviet countries on the consolidation of powder materials using electric current that passes through the powder sample and/or a conductive die-punch set-up. Having been published in Russian, many of the reviewed papers are not included in the mainstream electronic databases of the scientific articles and thus are not known to the scientific community. The present review is aimed at filling this information gap. In the paper, the electric current-assisted sintering techniques based on high- and low-voltage approaches are presented. The main results of the theoretical modeling of the processes of electromagnetic field-assisted consolidation of powder materials are discussed. Sintering experiments and related equipment are described and the major experimental results are analyzed. Sintering conditions required to achieve the desired properties of the sintered materials are provided for selected material systems. Tooling materials used in the electric current-assisted consolidation set-ups are also described. PMID:28788337

  15. Anxious arousal and anhedonic depression symptoms and the frequency of current marijuana use: testing the mediating role of marijuana-use coping motives among active users.

    PubMed

    Johnson, Kirsten A; Bonn-Miller, Marcel O; Leyro, Teresa M; Zvolensky, Michael J

    2009-07-01

    The present investigation examined anxious arousal and anhedonic depression symptoms in relation to frequency of past-30-day marijuana use, as well as the role of marijuana-use coping motives in terms of mediating this relation. The present sample included current young adult marijuana users (N = 154; 48.1% female; mean [SD] age = 20.75 [5.97] years) who were recruited via study flyers and printed advertisements in local newspapers placed throughout the Burlington, VT, community. After controlling for daily cigarette smoking rate, alcohol consumption, and gender, anxious arousal symptoms, but not anhedonic depression symptoms, were significantly and uniquely associated with the frequency of marijuana use. In addition, coping motives for marijuana use mediated the relation between anxious arousal symptoms and the frequency of current marijuana use. These results provide novel information related to the explanatory role of marijuana-use coping motives in the relation between anxious arousal symptoms and the frequency of marijuana use among young adult active users. Clinical implications for the current findings are discussed.

  16. "Being Good" at Maths: Fabricating Gender Subjectivity

    ERIC Educational Resources Information Center

    Chronaki, Anna; Pechtelidis, Yannis

    2012-01-01

    Current research in mathematics education places emphasis on the analysis of men and women's accounts about their life trajectories and choices for studying, working and developing a career that involves the learning and teaching of mathematics. Within this realm, the present study aims to highlight how mathematics, gender and subjectivity become…

  17. NASA Satellite Observations: A Unique Asset for the Study of the Environment and Implications for Public Health

    NASA Technical Reports Server (NTRS)

    Estes Sue M.

    2010-01-01

    This slide presentation highlights how satellite observation systems are assets for studying the environment in relation to public health. It includes information on current and future satellite observation systems, NASA's public health and safety research, surveillance projects, and NASA's public health partners.

  18. Memory Span and General Intelligence: A Latent-Variable Approach

    ERIC Educational Resources Information Center

    Colom, Roberto; Abad, Francisco J.; Rebollo, Irene; Chun Shih, Pei

    2005-01-01

    There are several studies showing that working memory and intelligence are strongly related. However, working memory tasks require simultaneous processing and storage, so the causes of their relationship with intelligence are currently a matter of discussion. The present study examined the simultaneous relationships among short-term memory (STM),…

  19. A Study of Predoctoral Student Support.

    ERIC Educational Resources Information Center

    Federal Interagency Committee on Education, Washington, DC. Student Support Study Group.

    This report of the Federal Interagency Committee on Education (FCIE) presents recommendations for expanding current federal support for graduate study. Federal agencies allocated $226.2 million for predoctoral fellowships and supported some 12.9% of the full-time graduate students in the US during the 1968-1969 school year. This support increased…

  20. Perceptions of Cyberbullying: An Assessment of Perceived Severity among College Students

    ERIC Educational Resources Information Center

    Sobba, Kristen N.; Paez, Rocio Alejandra; ten Bensel, Tusty

    2017-01-01

    Cyberbullying research has typically been focused on specific areas, such as victimization, offender characteristics and typologies, and psychological effects for victims; however, perceived severity of cyberbullying has been studied less extensively. Using data on college students, the present study expands the current knowledge on perceived…

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